Search results for: strains
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 981

Search results for: strains

171 Construction of Genetic Recombinant Yeasts with High Environmental Tolerance by Accumulation of Trehalose and Detoxication of Aldehyde

Authors: Yun-Chin Chung, Nileema Divate, Gen-Hung Chen, Pei-Ru Huang, Rupesh Divate

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Many environmental factors, such as glucose concentration, ethanol, temperature, osmotic pressure and pH, decrease the production rate of ethanol using yeast as a starter. Fermentation starters with high tolerance to various stresses are always demanded for brewing industry. Trehalose, a storage carbohydrate in cell wall of yeast, plays an important role in tolerance of environmental stress by preserving integrity of plasma membrane and stabilizing proteins. Furan aldehydes are toxic to yeast and the growth rate of yeast is significantly reduced if furan aldehydes were present in the fermentation medium. In yeast, aldehyde reductase is involved in the detoxification of reactive aldehydes and consequently the growth of yeast is improved. The aims of this study were to construct a genetic recombinant Saccharomyces cerevisiae or Pichia pastoris with furfural and HMF degrading and high ethanol tolerance capacities. Yeast strains were engineered by genetic recombination for overexpression of trehalose-6-phosphate synthase gene (tps1) and aldehyde reductase gene (ari1). TPS1 gene was cloned from S. cerevisiae by reverse transcription-polymerase chain reaction (RT-PCR) and then ligated with pGAPZαC vector. The constructed vector, pGAPZC-tps1, was transformed to recombinant yeasts strain with overexpression of ari1. The transformants with pGAPZC-tps1-ari1 were generated called STA (S. cerevisiae) and PTA (P. pastoris) with overexpression of tps1, ari1. PCR with tps1-specific primers and western blot with his-tag confirmed the gene insertion and protein expression of tps1 in the transformants, respectively. The neutral trehalase gene (nth1) of STA was successfully deleted and the novel strain STAΔN will be used for further study, including the measurement of trehalose concentration and ethanol, furfural tolerance assay.

Keywords: genetic recombinant, yeast, ethanol tolerance, trehalase, aldehyde reductase

Procedia PDF Downloads 398
170 SiO2-Ag+Chlorex vs SilverSulfaDiazine: An 'in vitro' and 'in vivo' Silver Challenge

Authors: Roberto Cassino, Valeria Dissette, Carlo Alberto Bignozzi, Daniele Pazzi

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Background and Aims: The aim of this work was to investigate, both ‘in vitro’ and ‘in vivo’, if the new SCX technology (SiO2-Ag+Chlorex) can easily defeat infections and it is really more effective than SSD (SilverSulfaDiazine). ‘In vitro’ methods: we tested ‘in vitro’ the effectiveness of both silver materials using a pool of 5 strains: Pseudomonas Aeruginosa, Staphylococcus aureus, Escherichia Coli, Enterococcus hirae and Candida Albicans. 100 µl of this pool have been seeded on Petri dishes and kept for 24 hours in incubation at 37 C°. ‘In vivo’ methods: we enrolled patients with multiple infectious chronic wounds (according with cutting & harding criteria for infection); after a qualitative evaluation of the wounds bacterial population, taking a sample by plug, we included in the study 6 patients for a total of 10 wounds, infected by one or more of the microorganisms used for the ‘in vitro’ test. The protocol consisted of a treatment with a spray powder of SSD every 48 hours for 14 days; in case of worsening we should have to start a new treatment with a spray powder containing silicon dioxide, ionic silver and chlorexidine (SiO2-Ag+Chlorex) every 48 hours for 14 days. We evaluated the number of clinical signs of infection and the disappearance or not of the wound edge erithema. ‘In vitro’ results: SSD demonstrated a wide zone of inhibition within 24 hours, but after 5 days there was no more signs of inhibition; on the contrary SCX had a good inhibition ring that lasted more than 5 days. ‘In vivo’ results: all wounds treated with SSD got worse; the signs of infection increased and the wound edge erithema did not disappear. According with the protocol, we treated then all wounds with SCX and they all improved within the period of observation with complete disappearance of clinical signs of infection and no more wound edge erithema. Conclusions: the study demonstrated the effectiveness of SiO2-Ag+Chlorex, especially in terms of long lasting antimicrobial action. We had the same results ‘in vitro’, so that there has been a perfect correspondence between the laboratory outcomes and the clinical ones.

Keywords: chronic wounds, infections, ionic silver, SSD

Procedia PDF Downloads 295
169 High Level Expression of Fluorinase in Escherichia Coli and Pichia Pastoris

Authors: Lee A. Browne, K. Rumbold

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The first fluorinating enzyme, 5'-fluoro-5'-deoxyadenosine synthase (fluorinase) was isolated from the soil bacterium Streptomyces cattleya. Such an enzyme, with the ability to catalyze a C-F bond, presents great potential as a biocatalyst. Naturally fluorinated compounds are extremely rare in nature. As a result, the number of fluorinases identified remains relatively few. The field of fluorination is almost completely synthetic. However, with the increasing demand for fluorinated organic compounds of commercial value in the agrochemical, pharmaceutical and materials industries, it has become necessary to utilize biologically based methods such as biocatalysts. A key step in this crucial process is the large-scale production of the fluorinase enzyme in considerable quantities for industrial applications. Thus, this study aimed to optimize expression of the fluorinase enzyme in both prokaryotic and eukaryotic expression systems in order to obtain high protein yields. The fluorinase gene was cloned into the pET 41b(+) and pPinkα-HC vectors and used to transform the expression hosts, E.coli BL21(DE3) and Pichia pastoris (PichiaPink™ strains) respectively. Expression trials were conducted to select optimal conditions for expression in both expression systems. Fluorinase catalyses a reaction between S-adenosyl-L-Methionine (SAM) and fluoride ion to produce 5'-fluorodeoxyadenosine (5'FDA) and L-Methionine. The activity of the enzyme was determined using HPLC by measuring the product of the reaction 5'FDA. A gradient mobile phase of 95:5 v/v 50mM potassium phosphate buffer to a final mobile phase containing 80:20 v/v 50mM potassium phosphate buffer and acetonitrile were used. This resulted in the complete separation of SAM and 5’-FDA which eluted at 1.3 minutes and 3.4 minutes respectively. This proved that the fluorinase enzyme was active. Optimising expression of the fluorinase enzyme was successful in both E.coli and PichiaPink™ where high expression levels in both expression systems were achieved. Protein production will be scaled up in PichiaPink™ using fermentation to achieve large-scale protein production. High level expression of protein is essential in biocatalysis for the availability of enzymes for industrial applications.

Keywords: biocatalyst, expression, fluorinase, PichiaPink™

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168 Potential of Native Microorganisms in Tagus Estuary

Authors: Ana C. Sousa, Beatriz C. Santos, Fátima N. Serralha

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The Tagus estuary is heavily affected by industrial and urban activities, making bioremediation studies crucial for environmental preservation. Fuel contamination in the area can arise from various anthropogenic sources, such as oil spills from shipping, fuel storage and transfer operations, and industrial discharges. These pollutants can cause severe harm to the ecosystem and the organisms, including humans, that inhabit it. Nonetheless, there are always natural organisms with the ability to resist these pollutants and transform them into non-toxic or harmless substances, which defines the process of bioremediation. Exploring the microbial communities existing in soil and their capacity to break down hydrocarbons has the potential to enhance the development of more efficient bioremediation approaches. The aim of this investigation was to explore the existence of hydrocarbonoclastic microorganisms in six locations within the Tagus estuary, three on the north bank: Trancão River, Praia Fluvial do Cais das Colinas and Praia de Algés, and three on the south bank: Praia Fluvial de Alcochete, Praia Fluvial de Alburrica, and Praia da Trafaria. In all studied locations, native microorganisms of the genus Pseudomonas were identified. The bioremediation rate of common hydrocarbons like gasoline, hexane, and toluene was assessed using the redox indicator 2,6-dichlorophenolindophenol (DCPIP). Effective hydrocarbon-degrading bacterial strains were identified in all analyzed areas, despite adverse environmental conditions. The highest bioremediation rates were achieved for gasoline (68%) in Alburrica, hexane (65%) in Algés, and toluene (79%) in Algés. Generally, the bacteria demonstrated efficient degradation of hydrocarbons added to the culture medium, with higher rates of aerobic biodegradation of hydrocarbons observed. These findings underscore the necessity for further in situ studies to better comprehend the relationship between native microbial communities and the potential for pollutant degradation in soil.

Keywords: biodegradability rate, hydrocarbonoclastic microorganisms, soil bioremediation, tagus estuary

Procedia PDF Downloads 79
167 An Experimental Investigation of Rehabilitation and Strengthening of Reinforced Concrete T-Beams Under Static Monotonic Increasing Loading

Authors: Salem Alsanusi, Abdulla Alakad

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An experimental investigation to study the behaviour of under flexure reinforced concrete T-Beams. Those Beams were loaded to pre-designated stress levels as percentage of calculated collapse loads. Repairing these beans by either reinforced concrete jacket, or by externally bolted steel plates were utilized. Twelve full scale beams were tested in this experimental program scheme. Eight out of the twelve beams were loaded under different loading levels. Tests were performed for the beams before and after repair with Reinforced Concrete Jacket (RCJ). The applied Load levels were 60%, 77% and 100% of the calculated collapse loads. The remaining four beams were tested before and after repair with Bolted Steel Plate (BSP). Furthermore, out previously mentioned four beams two beams were loaded to the calculated failure load 100% and the remaining two beams were not subjected to any load. The eight beams recorded for the RCJ test were repaired using reinforced concrete jacket. The four beams recorded for the BSP test were all repaired using steel plate at the bottom. All the strengthened beams were gradually loaded until failure occurs. However, in each loading case, the beams behaviour, before and after strengthening, were studied through close inspection of the cracking propagation, and by carrying out an extensive measurement of deformations and strength. The stress-strain curve for reinforcing steel and the failure strains measured in the tests were utilized in the calculation of failure load for the beams before and after strengthening. As a result, the calculated failure loads were close to the actual failure tests in case of beams before repair, ranging from 85% to 90% and also in case of beams repaired by reinforced concrete jacket ranging from 70% to 85%. The results were in case of beams repaired by bolted steel plates ranging from (50% to 85%). It was observed that both jacketing and bolted steel plate methods could effectively restore the full flexure capacity of the damaged beams. However, the reinforced jacket has increased the failure load by about 67%, whereas the bolted steel plates recovered the failure load.

Keywords: rehabilitation, strengthening, reinforced concrete, beams deflection, bending stresses

Procedia PDF Downloads 286
166 The Onset of Ironing during Casing Expansion

Authors: W. Assaad, D. Wilmink, H. R. Pasaribu, H. J. M. Geijselaers

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Shell has developed a mono-diameter well concept for oil and gas wells as opposed to the traditional telescopic well design. A Mono-diameter well design allows well to have a single inner diameter from the surface all the way down to reservoir to increase production capacity, reduce material cost and reduce environmental footprint. This is achieved by expansion of liners (casing string) concerned using an expansion tool (e.g. a cone). Since the well is drilled in stages and liners are inserted to support the borehole, overlap sections between consecutive liners exist which should be expanded. At overlap, the previously inserted casing which can be expanded or unexpanded is called the host casing and the newly inserted casing is called the expandable casing. When the cone enters the overlap section, an expandable casing is expanded against a host casing, a cured cement layer and formation. In overlap expansion, ironing or lengthening may appear instead of shortening in the expandable casing when the pressure exerted by the host casing, cured cement layer and formation exceeds a certain limit. This pressure is related to cement strength, thickness of cement layer, host casing material mechanical properties, host casing thickness, formation type and formation strength. Ironing can cause implications that hinder the deployment of the technology. Therefore, the understanding of ironing becomes essential. A physical model is built in-house to calculate expansion forces, stresses, strains and post expansion casing dimensions under different conditions. In this study, only free casing and overlap expansion of two casings are addressed while the cement and formation will be incorporated in future study. Since the axial strain can be predicted by the physical model, the onset of ironing can be confirmed. In addition, this model helps in understanding ironing and the parameters influencing it. Finally, the physical model is validated with Finite Element (FE) simulations and small-scale experiments. The results of the study confirm that high pressure leads to ironing when the casing is expanded in tension mode.

Keywords: casing expansion, cement, formation, metal forming, plasticity, well design

Procedia PDF Downloads 159
165 Bacteriophage Lysis Of Physiologically Stressed Listeria Monocytogenes In A Simulated Seafood Processing Environment

Authors: Geevika J. Ganegama Arachchi, Steve H. Flint, Lynn McIntyre, Cristina D. Cruz, Beatrice M. Dias-Wanigasekera, Craig Billington, J. Andrew Hudson, Anthony N. Mutukumira

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In seafood processing plants, Listeriamonocytogenes(L. monocytogenes)likely exists in a metabolically stressed state due to the nutrient-deficient environment, processing treatments such as heating, curing, drying, and freezing, and exposure to detergents and disinfectants. Stressed L. monocytogenes cells have been shown to be as pathogenic as unstressed cells. This study investigated lytic efficacy of (LiMN4L, LiMN4p, and LiMN17) which were previouslycharacterized as virulent against physiologically stressed cells of three seafood borne L. monocytogenesstrains (19CO9, 19DO3, and 19EO3).Physiologically compromised cells ofL. monocytogenesstrains were prepared by aging cultures in TrypticaseSoy Broth at 15±1°C for 72 h; heat injuringcultures at 54±1 - 55±1°C for 40 - 60 min;salt-stressing cultures in Milli-Q water were incubated at 25±1°C in darkness for three weeks; and incubating cultures in 9% (w/v) NaCl at 15±1°C for 72 h. Low concentrations of physiologically compromised cells of three L. monocytogenesstrainswere challenged in vitrowith high titre of three phages in separate experiments using Fish Broth medium (aqueous fish extract) at 15 °C in order to mimic the environment of seafood processing plant. Each phage, when present at ≈9 log10 PFU/ml, reduced late exponential phase cells of L. monocytogenes suspended in fish protein broth at ≈2-3 log10 CFU/ml to a non-detectable level (< 10 CFU/ml). Each phage, when present at ≈8.5 log10 PFU/ml, reduced both heat-injured cells present at 2.5-3.6 log10 CFU/ml and starved cells that were showed coccoid shape, present at ≈2-3 log10 CFU/ml to < 10 CFU/ml after 30 min. Phages also reduced salt-stressed cellspresent at ≈3 log10 CFU/ml by > 2 log10. L. monocytogenes (≈8 log10 CFU/ml) were reduced to below the detection limit (1 CFU/ml) by the three successive phage infections over 16 h, indicating that emergence of spontaneous phage resistance was infrequent. The three virulent phages showed high decontamination potential for physiologically stressed L. monocytogenes strains from seafood processing environments.

Keywords: physiologically stressed L. monocytogenes, heat injured, seafood processing environment, virulent phage

Procedia PDF Downloads 114
164 Introducing Two Species of Parastagonospora (Phaeosphaeriaceae) on Grasses from Italy and Russia, Based on Morphology and Phylogeny

Authors: Ishani D. Goonasekara, Erio Camporesi, Timur Bulgakov, Rungtiwa Phookamsak, Kevin D. Hyde

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Phaeosphaeriaceae comprises a large number of species occurring mainly on grasses and cereal crops as endophytes, saprobes and especially pathogens. Parastagonospora is an important genus in Phaeosphaeriaceae that includes pathogens causing leaf and glume blotch on cereal crops. Currently, there are fifteen Parastagonospora species described, including both pathogens and saprobes. In this study, one sexual morph species and an asexual morph species, occurring as saprobes on members of Poaceae are introduced based on morphology and a combined molecular analysis of the LSU, SSU, ITS, and RPB2 gene sequence data. The sexual morph species Parastagonospora elymi was isolated from a Russian sample of Elymus repens, a grass commonly known as couch grass, and important for grazing animals, as a weed and used in traditional Austrian medicine. P. elymi is similar to the sexual morph of P. avenae in having cylindrical asci, bearing 8, overlapping biseriate, fusiform ascospores but can be distinguished by its subglobose to conical shaped, wider ascomata. In addition, no sheath was observed surrounding the ascospores. The asexual morph species was isolated from a specimen from Italy, on Dactylis glomerata, a commonly found grass distributed in temperate regions. It is introduced as Parastagonospora macrouniseptata, a coelomycete, and bears a close resemblance to P. allouniseptata and P. uniseptata in having globose to subglobose, pycnidial conidiomata and hyaline, cylindrical, 1-septate conidia. However, the new species could be distinguished in having much larger conidiomata. In the phylogenetic analysis which consisted of a maximum likelihood and Bayesian analysis P. elymi showed low bootstrap support, but well segregated from other strains within the Parastagonospora clade. P. neoallouniseptata formed a sister clade with P. allouniseptata with high statistical support.

Keywords: dothideomycetes, multi-gene analysis, Poaceae, saprobes, taxonomy

Procedia PDF Downloads 98
163 Alternative Housing Systems: Influence on Blood Profile of Egg-Type Chickens in Humid Tropics

Authors: Olufemi M. Alabi, Foluke A. Aderemi, Adebayo A. Adewumi, Banwo O. Alabi

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General well-being of animals is of paramount interest in some developed countries and of global importance hence the shift onto alternative housing systems for egg-type chickens as replacement for conventional battery cage system. However, there is paucity of information on the effect of this shift on physiological status of the hens to judge their health via the blood profile. Therefore, investigation was carried out on two strains of hen kept in three different housing systems in humid tropics to evaluate changes in their blood parameters. 108, 17-weeks old super black (SBL) hens and 108, 17-weeks old super brown (SBR) hens were randomly allotted to three different intensive systems Partitioned Conventional Cage (PCC), Extended Conventional Cage (ECC) and Deep Litter System (DLS) in a randomized complete block design with 36 hens per housing system, each with three replicates. The experiment lasted 37 weeks during which blood samples were collected at 18th week of age and bi-weekly thereafter for analyses. Parameters measured are packed cell volume (PCV), hemoglobin concentration (Hb), red blood counts (RBC), white blood counts (WBC) and serum metabolites such as total protein (TP), albumin (Alb), globulin (Glb), glucose, cholesterol, urea, bilirubin, serum cortisol while blood indices such as mean corpuscular hemoglobin (MCH), mean cell volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) were calculated. The hematological values of the hens were not significantly (p>0.05) affected by the housing system and strain, so also the serum metabolites except for the serum cortisol which was significantly (p<0.05) affected by the housing system only. Hens housed on PCC had higher values (20.05 ng/ml for SBL and 20.55 ng/ml for SBR) followed by hens on ECC (18.15ng/ml for SBL and 18.38ng/ml for SBL) while hens on DLS had the lowest value (16.50ng/ml for SBL and 16.00ng/ml for SBR) thereby confirming indication of stress with conventionally caged birds. Alternative housing systems can also be adopted for egg-type chickens in the humid tropics from welfare point of view with the results of this work confirming stress among caged hens.

Keywords: blood, housing, humid-tropics, layers

Procedia PDF Downloads 445
162 Zingiberaceous Plants as a Source of Anti-Bacterial Activity: Targeting Bacterial Cell Division Protein (FtsZ)

Authors: S. Reshma Reghu, Shiburaj Sugathan, T. G. Nandu, K. B. Ramesh Kumar, Mathew Dan

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Bacterial diseases are considered to be one of the most prevalent health hazards in the developing world and many bacteria are becoming resistant to existing antibiotics making the treatment ineffective. Thus, it is necessary to find novel targets and develop new antibacterial drugs with a novel mechanism of action. The process of bacterial cell division is a novel and attractive target for new antibacterial drug discovery. FtsZ, a homolog of eukaryotic tubulin, is the major protein of the bacterial cell division machinery and is considered as an important antibacterial drug target. Zingiberaceae, the Ginger family consists of aromatic herbs with creeping rhizomes. Many of these plants have antimicrobial properties.This study aimed to determine the anti-bacterial activity of selected Zingiberaceous plants by targeting bacterial cell division protein, FtsZ. Essential oils and methanol extracts of Amomum ghaticum, Alpinia galanga, Kaempferia galanga, K. rotunda, and Zingiber officinale were tested to find its antibacterial efficiency using disc diffusion method against authentic bacterial strains obtained from MTCC (India). Essential oil isolated from A.galanga and Z.officinale were further assayed for FtsZ inhibition assay following non-radioactive malachite green-phosphomolybdate assay using E. coli FtsZ protein obtained from Cytoskelton Inc., USA. Z.officinale essential oil possess FtsZ inhibitory property. A molecular docking study was conducted with the known bioactive compounds of Z. officinale as ligands with the E. coli FtsZ protein homology model. Some of the major constituents of this plant like catechin, epicatechin, and gingerol possess agreeable docking scores. The results of this study revealed that several chemical constituents in Ginger plants can be utilised as potential source of antibacterial activity and it can warrant further investigation through drug discovery studies.

Keywords: antibacterial, FtsZ, zingiberaceae, docking

Procedia PDF Downloads 449
161 Inhibition of Escherichia coli and Salmonella spp. By Traditional Phytomedicines That Are Commonly Used to Treat Gastroenteritis in Zimbabwe

Authors: Constance Chivengwa, Tinashe Mandimutsira, Jephris Gere, Charles Magogo, Irene Chikanza, Jerneja Vidmar, Walter Chingwaru

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The use of traditional methods in the management of diarrhoea has remained a common practice among the indigenous African tribes of Southern Africa. Despite the widespread use of traditional medicines in Zimbabwe, very little research validating the activities of phytomedicines against diarrhoea, as claimed by the Shona people of Zimbabwe, has been reported. This study sought to determine the efficacies of the plants that are frequently used to treat stomach complaints, namely Dicoma anomala, Cassia abbreviata, Lannea edulis and Peltophorum africanum against Escherichia coli (an indicator of faecal contamination of water, and whose strains such as EHEC (O157), ETEC and EPEC, are responsible for a number of outbreaks of diarrhoea) and Salmonella spp. Ethanol and aqueous extracts from these plants were obtained, evaporated, dried and stored. The dried extracts were reconstituted and diluted 10-fold in nutrient broth (from 100 to 0.1 microgram/mL) and tested for inhibition against the bacteria. L. edulis exhibited the best antimicrobial effect (minimum inhibition concentration = 10 microgram/mL for both extracts and microorganisms). Runners up to L. edulis were C. abbreviata (20 microgram/mL for both microorganisms) and P. africanum (20 and 30 microgram/mL respectively). Interestingly, D. anomala, which is widely considered panacea in African medicinal practices, showed low antimicrobial activity (60 and 100 microgram/mL respectively). The high antimicrobial activity of L. edulis can be explained by its content of flavonoids, tannins, alkylphenols (cardonol 7 and cardonol 13) and dihydroalkylhexenones. The antimicrobial activities of C. abbreviata can be linked to its content of anthraquinones and triterpenoids. P. africanum is known to contain benzenoids, flavanols, flavonols, terpenes, xanthone and coumarins. This study therefore demonstrated that, among the plants that are used against diarrhoea in African traditional medicine, L. edulis is a clear winner against E. coli and Salmonella spp. Activity guided extraction is encouraged to establish the complement of compounds that have antimicrobial activities.

Keywords: diarrhoea, Escherichia coli, Salmonella, phytomedicine, MIC, Zimbabwe

Procedia PDF Downloads 344
160 Evaluation of Antimicrobial Efficacy of Nanofluid Containing Carbon Nanotubes Functionalized with Antibiotic on Urinary Tract Infection

Authors: Erfan Rahimi, Hadi Bahari Far, Mojgan Shikhpour

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Background: Urinary tract infection is one of the most common nosocomial infections, especially among women. E. coli is one of the main causes of urinary tract infections and one of the most common antibiotics to fight this bacterium is ampicillin. As conventional antibiotics led to bacterial antibiotic resistance, modification of the pure drugs can address this issue. The aim of this study was to prepare nanofluids containing carbon nanotubes conjugated with ampicillin to improve drug performance and reduce antibiotic resistance. Methods: Multi-walled carbon nanotubes (MWCNTs) were activated with thionyl chloride by reflux system and nanofluids containing antibiotics were prepared by ultrasonic method. The properties of the prepared nano-drug were investigated by general element analysis, infrared spectroscopy, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. After the treatment of the desired strain with nanofluid, microbial studies were performed to evaluate the antibacterial effects and molecular studies were carried out to measure the expression of the resistance gene AcrAB. Result: We have shown that the antimicrobial effect of ampicillin-functionalized MWCNTs at low concentrations performed better than that of the conventional drug in both resistant and ATCC strains. Also, a decrease in antibiotic resistance of bacteria treated with ampicillin-functionalized MWCNTs compared to the pure drug was observed. Also, ampicillin-functionalized MWCNTs downregulated the expression of AcrAB in treated bacteria. Conclusion: Because carbon nanotubes are capable of destroying the bacterial wall, which provides antibiotic resistance features in bacteria, their usage in the form of nanofluids can make lower dosages (about three times less) than that of the pure drug more effective. Additionally, the expression of the bacterial resistance gene AcrAB decreased, thereby reducing antibiotic resistance and improving drug performance against bacteria.

Keywords: urinary tract infection, antibiotic resistance, carbon nanotube, nanofluid

Procedia PDF Downloads 123
159 Bean in Turkey: Characterization, Inter Gene Pool Hybridization Events, Breeding, Utilizations

Authors: Faheem Shahzad Baloch, Muhammad Azhar Nadeem, Muhammad Amjad Nawaz, Ephrem Habyarimana, Gonul Comertpay, Tolga Karakoy, Rustu Hatipoglu, Mehmet Zahit Yeken, Vahdettin Ciftci

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Turkey is considered a bridge between Europe, Asia, and Africa and possibly played an important role in the distribution of many crops including common bean. Hundreds of common bean landraces can be found in Turkey, particularly in farmers’ fields, and they consistently contribute to the overall production. To investigate the existing genetic diversity and hybridization events between the Andean and Mesoamerican gene pools in the Turkish common bean, 188 common bean accessions (182 landraces and 6 modern cultivars as controls) were collected from 19 different Turkish geographic regions. These accessions were characterized using phenotypic data (growth habit and seed weight), geographic provenance, 12557 high-quality whole-genome DArTseq markers, and 3767 novel DArTseq loci were also identified. The clustering algorithms resolved the Turkish common bean landrace germplasm into the two recognized gene pools, the Mesoamerican and Andean gene pools. Hybridization events were observed in both gene pools (14.36% of the accessions) but mostly in the Mesoamerican (7.97% of the accessions), and was low relative to previous European studies. The lower level of hybridization witnessed the existence of Turkish common bean germplasm in its original form as compared to Europe. Mesoamerican gene pool reflected a higher level of diversity, while the Andean gene pool was predominant (56.91% of the accessions), but genetically less diverse and phenotypically more pure, reflecting farmers greater preference for the Andean gene pool. We also found some genetically distinct landraces and overall, a meaningful level of genetic variability which can be used by the scientific community in breeding efforts to develop superior common bean strains.

Keywords: bean germplasm, DArTseq markers, genotyping by sequencing, Turkey, whole genome diversity

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158 Implications for Counseling and Service Delivery on the Psychological Trajectories of Women Undergoing in Vitro Fertilization (IVF) Treatment in Hong Kong

Authors: Tong Mei Yan

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Introduction: The experience of infertility could be excruciating but has not received much attention in Hong Kong. The strong Confucian culture pressures couples to continue their family lineage resulting in women facing more stress than men in the social-cultural milieu. In Vitro Fertilization (IVF) treatment is one of the common ways to deal with the problem. Abundant literature exists the psychological trajectories of people receiving IVF treatment in Europe, the USA and other east Asian societies but not in Hong Kong. Aim: This study aims to highlight the circumstances and needs of the women before, during and after IVF treatment through examining their lived experiences. It is hoped that the public, once informed of regarding their tribulations and needs , would support the adequate provision of the required psychological support . Methods: Qualitative analysis was adopted in this study. In-depth interviews were conducted with six women who have undergone at least one complete cycle of IVF treatment within the past five years. Data was analyzed through thematic analysis and narrative analysis. Results: 4 broad themes were found, including (i) emotional responses; (ii) experiences in medical consultation; (iii) impacts of the treatment; and (iv) their coping strategies. Additionally, specific events in three cases were chosen for narrative analysis to further examine their unresolved emotional distress and the ethical issues. Conclusion: IVF treatment distressed the interviewees immensely, both physically and psychologically, with the negative emotions outweighing their physical strains, a result unexpected by all of the interviewees. The pressure for lineage continuation, the demanding treatment process and the dearth of support from health professionals all contribute to their emotional pain which could linger for both successful and unsuccessful cases. Although a number of coping strategies were attempted, most of them completely failed to ease their psychological tension. The findings of this study therefore evidence the need for psychological support for this population. A service model to cater their needs of IVF treatment before, during and after treatment is therefore proposed.

Keywords: coping strategies, emotional experiences, impacts of IVF, infertility, IVF treatment, medical experiences

Procedia PDF Downloads 61
157 Physicochemical and Functional significance of Two Lychee (Litchi chinensis Sonn.) Cultivars Gola and Surakhi from Pakistan

Authors: Naila Safdar, Faria Riasat, Azra Yasmin

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Lychee is an emerging fruit crop in Pakistan. Two famous cultivars of lychee, Gola and Surakhi, were collected from Khanpur Orchard, Pakistan and their whole fruit (including peel, pulp and seed) was investigated for pomological features and therapeutic activities. Both cultivars differ in shape and size with Gola having large size (3.27cm length, 2.36cm width) and more flesh to seed ratio (8.65g). FTIR spectroscopy and phytochemical tests confirmed presence of different bioactive compounds like phenol, flavonoids, quinones, anthraquinones, tannins, glycosides, and alkaloids, in both lychee fruits. Atomic absorption spectroscopy indicated an increased amount of potassium, magnesium, sodium, iron, and calcium in Gola and Surakhi fruits. Small amount of trace metals, zinc and copper, were also detected in lychee fruit, while heavy metals lead, mercury, and nickel were absent. These two lychee cultivars were also screened for antitumor activity by Potato disc assay with maximum antitumor activity shown by aqueous extract of Surakhi seed (77%) followed by aqueous extract of Gola pulp (74%). Antimicrobial activity of fruit parts was checked by agar well diffusion method against six bacterial strains Enterococcus faecium, Enterococcus faecalis, Staphylococcus aureus, Bacillus subtilis, Bacillus sp. MB083, and Bacillus sp. MB141. Highest antimicrobial activity was shown by methanolic extract of Gola pulp (27mm ± 0.70) and seed (19.5mm ± 0.712) against Enterococcus faecalis. DPPH scavenging assay revealed highest antioxidant activity by aqueous extract of Gola peel (98.10%) followed by n-hexane extract of Surakhi peel (97.73%). Results obtained by reducing power assay also corroborated with the results of DPPH scavenging activity.

Keywords: antimicrobial evaluation, antitumor assay, gola, phytoconstituents, reactive oxygen species, Surakhi

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156 Evaluation of Paper Effluent with Two Bacterial Strain and Their Consortia

Authors: Priya Tomar, Pallavi Mittal

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As industrialization is inevitable and progress with rapid acceleration, the need for innovative ways to get rid of waste has increased. Recent advancement in bioresource technology paves novel ideas for recycling of factory waste that has been polluting the agro-industry, soil and water bodies. Paper industries in India are in a considerable number, where molasses and impure alcohol are still being used as raw materials for manufacturing of paper. Paper mills based on nonconventional agro residues are being encouraged due to increased demand of paper and acute shortage of forest-based raw materials. The colouring body present in the wastewater from pulp and paper mill is organic in nature and is comprised of wood extractives, tannin, resins, synthetic dyes, lignin and its degradation products formed by the action of chlorine on lignin which imparts an offensive colour to the water. These mills use different chemical process for paper manufacturing due to which lignified chemicals are released into the environment. Therefore, the chemical oxygen demand (COD) of the emanating stream is quite high. This paper presents some new techniques that were developed for the efficiency of bioremediation on paper industry. A short introduction to paper industry and a variety of presently available methods of bioremediation on paper industry and different strategies are also discussed here. For solving the above problem, two bacterial strains (Pseudomonas aeruginosa and Bacillus subtilis) and their consortia (Pseudomonas aeruginosa and Bacillus subtilis) were utilized for the pulp and paper mill effluent. Pseudomonas aeruginosa and Bacillus subtilis named as T–1, T–2, T–3, T–4, T–5, T–6, for the decolourisation of paper industry effluent. The results indicated that a maximum colour reduction is (60.5%) achieved by Pseudomonas aeruginosa and COD reduction is (88.8%) achieved by Bacillus subtilis, maximum pH changes is (4.23) achieved by Pseudomonas aeruginosa, TSS reduction is (2.09 %) achieved by Bacillus subtilis, and TDS reduction is (0.95 %) achieved by Bacillus subtilis. When the wastewater was supplemented with carbon (glucose) and nitrogen (yeast extract) source and data revealed the efficiency of Bacillus subtilis, having more with glucose than Pseudomonas aeruginosa.

Keywords: bioremediation, paper and pulp mill effluent, treated effluent, lignin

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155 Two-Protein Modified Gold Nanoparticles for Serological Diagnosis of Borreliosis

Authors: Mohammed Alasel, Michael Keusgen

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Gold is a noble metal; in its nano-scale level (e.g. spherical nanoparticles), the conduction electrons are triggered to collectively oscillate with a resonant frequency when certain wavelengths of electromagnetic radiation interact with its surface; this phenomenon is known as surface plasmon resonance (SPR). SPR is responsible for giving the gold nanoparticles its intense red color depending mainly on its size, shape and distance between nanoparticles. A decreased distance between gold nanoparticles results in aggregation of them causing a change in color from red to blue. This aggregation enables gold nanoparticles to serve as a sensitive biosensoric indicator. In the proposed work, gold nanoparticles were modified with two proteins: i) Borrelia antigen, variable lipoprotein surface-exposed protein (VlsE), and ii) protein A. VlsE antigen induces a strong antibody response against Lyme disease and can be detected from early to late phase during the disease in humans infected with Borrelia. In addition, it shows low cross-reaction with the other non-pathogenic Borrelia strains. The high specificity of VlsE antigen to anti-Borrelia antibodies, combined simultaneously with the high specificity of protein A to the Fc region of all IgG human antibodies, was utilized to develop a rapid test for serological point of care diagnosis of borreliosis in human serum. Only in the presence of anti-Borrelia antibodies in the serum probe, an aggregation of gold nanoparticles can be observed, which is visible by a concentration-dependent colour shift from red (low IgG) to blue (high IgG). Experiments showed it is clearly possible to distinguish between positive and negative sera samples using a simple suspension of the two-protein modified gold nanoparticles in a very short time (30 minutes). The proposed work showed the potential of using such modified gold nanoparticles generally for serological diagnosis. Improved specificity and reduced assay time can be archived in applying increased salt concentrations combined with decreased pH values (pH 5).

Keywords: gold nanoparticles, gold aggregation, serological diagnosis, protein A, lyme borreliosis

Procedia PDF Downloads 367
154 Investigating the Antimicrobial Activity of Essential Oil Derived from Pistacia atlantica Gum against Extensively Drug-Resistant Gram-Negative Acinetobacter baumannii

Authors: Zhala Ahmad, Zainab Lazim, Haider Hamzah

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Bacterial resistance is a pressing global health issue, with multidrug-resistant (MDR), extensively drug-resistant (XDR), and pandrug-resistant (PDR) strains to pose a serious threat. In this context, researchers are investigating effective, safe, and affordable metabolites to combat these pathogens. This study focuses on gum essential oil (GEO) extracted from Pistacia atlantica and its activity and the mechanism of action against XDR Gram-negative Acinetobacter baumannii. GEO was extracted by hydrodistillation and analyzed using GC-MS. Eleven A. baumannii isolates were collected from the ward environment of Burn and Plastic Surgery Hospital in Al Sulaymaniyah City, Iraq. They were identified using the VITEK 2 system, 16S rRNA gene, and confirmed with the blaₒₓₐ₋₅₁ gene; A. baumannii ATCC 19606 was used as a reference strain. The isolates were identified as resistant to twelve different antibiotics spanning six distinct antibiotic classes while showing susceptibility to tetracycline and trimethoprim. Over 40 chemical constituents were detected in the gum's essential oils, with α-pinene being the most abundant. GEO was found to inhibit the growth of A. baumannii isolates; the minimum inhibitory concentration (MIC) of GEO was 2.5 µl/ml. GEO induced protein leakage, phosphate, and potassium ion efflux, distorted cell morphology, and cell death in the tested bacteria. GEO exhibited bacterial clearance and anti-adhesion activity using Band-Aids. This study's findings suggest that GEO could be used as a potential alternative treatment for infectious diseases caused by XRD pathogens, shedding further light on the importance of GEO in biomedical applications. Future studies must focus on generating clinically feasible sources of GEO for testing in small animal models before proceeding to human trials, ensuring safe and effective translation from the laboratory to the clinic.

Keywords: antibiotic resistance, Acinetobacter baumannii, essential oils, Pistacia atlantica, alpha-pinene

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153 The Molecular Analysis of Effect of Phytohormones and Spermidine on Tomato Growth under Biotic Stress

Authors: Rumana Keyani, Haleema Sadia, Asia Nosheen, Rabia Naz, Humaira Yasmin, Sidra Zahoor

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Tomato is a significant crop of the world and is one of the staple foods of Pakistan. A vast number of plant pathogens from simple viruses to complex parasites cause diseases in tomatoes but fungal infection in our country is quite high. Sometimes the symptoms are too harsh destroying the crop altogether. Countries like our own with continuously increasing massive population and limited resources cannot afford such an economic loss. There is an array of morphological, genetic, biochemical and molecular processes involved in plant resistance mechanisms to biotic stress. The study of different metabolic pathways like Jasmonic acid (JA) pathways and most importantly signaling molecules like ROS/RNS and their redoxin enzymes i.e. TRX and NRX is crucial to disease management, contributing to healthy plant growth. So, improving tolerance in crop plants against biotic stresses is a dire need of our country and world as whole. In the current study, fungal pathogenic strains Alternaria solani and Rhizoctonia solani were used to inoculate tomatoes to check the defense responses of tomato plant against these pathogens at molecular as well as phenotypic level with jasmonic acid and spermidine pretreatment. All the growth parameters (root and shoot length, dry and weight root, shoot weight measured 7 days post-inoculation, exhibited that infection drastically declined the growth of the plant whereas jasmonic acid and spermidine assisted the plants to cope up with the infection. Thus, JA and Spermidine treatments maintained comparatively better growth factors. Antioxidant assays and expression analysis through real time quantitative PCR following time course experiment at 24, 48 and 72 hours intervals also exhibited that activation of JA defense genes and a polyamine Spermidine helps in mediating tomato responses against fungal infection when used alone but the two treatments combined mask the effect of each other.

Keywords: fungal infection, jasmonic acid defence, tomato, spermidine

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152 Direct Fed Microbes: A Better Approach to Maximize Utilization of Roughages in Tropical Ruminants

Authors: Muhammad Adeel Arshad, Shaukat Ali Bhatti, Faiz-ul Hassan

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Manipulating microbial ecosystem in the rumen is considered as an important strategy to optimize production efficiency in ruminants. In the past, antibiotics and synthetic chemical compounds have been used for the manipulation of rumen fermentation. However, since the non-therapeutic use of antibiotics has been banned, efforts are being focused to search out safe alternative products. In tropics, crop residues and forage grazing are major dietary sources for ruminants. Poor digestibility and utilization of these feedstuffs by animals is a limiting factor to exploit the full potential of ruminants in this area. Hence, there is a need to enhance the utilization of these available feeding resources. One of the potential strategies in this regard is the use of direct-fed microbes. Bacteria and fungi are mostly used as direct-fed microbes to improve animal health and productivity. Commonly used bacterial species include lactic acid-producing and utilizing bacteria (Lactobacillus, Streptococcus, Enterococcus, Bifidobacterium, and Bacillus) and fungal species of yeast are Saccharomyces and Aspergillus. Direct-fed microbes modulate microbial balance in the gastrointestinal tract through the competitive exclusion of pathogenic species and favoring beneficial microbes. Improvement in weight gain and feed efficiency has been observed as a result of feeding direct-fed bacteria. The use of fungi as a direct-fed microbe may prevent excessive production of lactate and harmful oxygen in the rumen leading to better feed digestibility. However, the mechanistic mode of action for bacterial or fungal direct-fed microbes has not been established yet. Various reports have confirmed an increase in dry matter intake, milk yield, and milk contents in response to the administration of direct-fed microbes. However, the application of a direct-fed microbe has shown variable responses mainly attributed to dosages and strains of microbes. Nonetheless, it is concluded that the inclusion of direct-fed microbes may mediate the rumen ecosystem to manage lactic acid production and utilization in both clinical and sub-acute rumen acidosis.

Keywords: microbes, roughages, rumen, feed efficiency, production, fermentation

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151 In-Situ Sludge Minimization Using Integrated Moving Bed Biofilm Reactor for Industrial Wastewater Treatment

Authors: Vijay Sodhi, Charanjit Singh, Neelam Sodhi, Puneet P. S. Cheema, Reena Sharma, Mithilesh K. Jha

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The management and secure disposal of the biosludge generated from widely commercialized conventional activated sludge (CAS) treatments become a potential environmental issue. Thus, a sustainable technological upgradation to the CAS for sludge yield minimization has recently been gained serious attention of the scientific community. A number of recently reported studies effectively addressed the remedial technological advancements that in monopoly limited to the municipal wastewater. Moreover, the critical review of the literature signifies side-stream sludge minimization as a complex task to maintain. In this work, therefore, a hybrid moving bed biofilm reactor (MBBR) configuration (named as AMOMOX process) for in-situ minimization of the excess biosludge generated from high organic strength tannery wastewater has been demonstrated. The AMOMOX collectively stands for anoxic MBBR (as AM), aerobic MBBR (OM) and an oxic CAS (OX). The AMOMOX configuration involved a combined arrangement of an anoxic MBBR and oxic MBBR coupled with the aerobic CAS. The AMOMOX system was run in parallel with an identical CAS reactor. Both system configurations were fed with same influent to judge the real-time operational changes. For the AMOMOX process, the strict maintenance of operational strategies resulted about 95% removal of NH4-N and SCOD from tannery wastewater. Here, the nourishment of filamentous microbiota and purposeful promotion of cell-lysis effectively sustained sludge yield (Yobs) lowering upto 0.51 kgVSS/kgCOD. As a result, the volatile sludge scarcity apparent in the AMOMOX system succeeded upto 47% reduction of the excess biosludge. The corroborated was further supported by FE-SEM imaging and thermogravimetric analysis. However, the detection of microbial strains habitat underlying extended SRT (23-26 days) of the AMOMOX system would be the matter of further research.

Keywords: tannery wastewater, moving bed biofilm reactor, sludhe yield, sludge minimization, solids retention time

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150 Typification and Determination of Antibiotic Susceptibility Profiles with E Test Methods of Anaerobic Gram Negative Bacilli Isolated from Various Clinical Specimen

Authors: Cengiz Demir, Recep Keşli, Gülşah Aşık

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Objective: This study was carried out with the purpose of defining by using the E test method and determining the antibiotic resistance profiles of Gram-negative anaerobic bacilli isolated from various clinical specimens obtained from patients with suspected anaerobic infections and referred to Medical Microbiology Laboratory of Afyon Kocatepe University, ANS Application and Research Hospital. Methods: Two hundred and seventy eight clinical specimens were examined for isolation of the anaerobic bacteria in Medical Microbiology Laboratory between the 1st November 2014 and 30th October 2015. Specimens were cultivated by using Scheadler agar that 5% defibrinated sheep blood added, and Scheadler broth. The isolated anaerobic Gram-negative bacilli were identified conventional methods and Vitek 2 (ANC ID Card, bioMerieux, France) cards. Antibiotic resistance rates against to penicillin G, clindamycin, cefoxitin, metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem were determined with E-test method for each isolate. Results: Of the isolated twenty-eight anaerobic gram negative bacilli fourteen were identified as the B. fragilis group, 9 were Prevotella group, and 5 were Fusobacterium group. The highest resistance rate was found against penicillin (78.5%) and resistance rates against clindamycin and cefoxitin were found as 17.8% and 21.4%, respectively. Against to the; metronidazole, moxifloxacin, imipenem, meropenem, ertapenem and doripenem, no resistance was found. Conclusion: Since high rate resistance has been detected against to penicillin in the study penicillin should not be preferred in empirical treatment. Cefoxitin can be preferred in empirical treatment; however, carrying out the antibiotic sensitivity testing will be more proper and beneficial. No resistance was observed against carbapenem group antibiotics and metronidazole; so that reason, these antibiotics should be reserved for treatment of infectious caused by resistant strains in the future.

Keywords: anaerobic gram-negative bacilli, anaerobe, antibiotics and resistance profiles, e-test method

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149 Effect of Molecular Weight Distribution on Toughening Performance of Polybutadiene in Polystyrene

Authors: Mohamad Mohsen Yavarizadeh

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Polystyrene (PS) and related homopolymers are brittle materials that typically fail in tensile tests at very low strains. These polymers can be toughened by the addition of rubbery particles which initiate a large number of crazes that produce substantial plastic strain at relatively low stresses. Considerable energy is dissipated in the formation of these crazes, producing a relatively tough material that shows an impact toughness of more than 5 times of pure PS. While cross linking of rubbery phase is necessary in aforementioned mechanism of toughening, another mechanism of toughening was also introduced in which low molecular weight liquid rubbers can also toughen PS when dispersed in the form of small pools in the glassy matrix without any cross linking. However, this new mechanism which is based on local plasticization, fails to act properly at high strain rate deformations, i.e. impact tests. In this work, the idea of combination of these two mechanisms was tried. To do so, Polybutadiene rubbers (PB) with bimodal distribution of molecular weight were prepared in which, comparable fractions of very high and very low molecular weight rubbers were mixed. Incorporation of these materials in PS matrix in a reactive process resulted in more significant increases in toughness of PS. In other words, although low molecular weight PB is ineffective in high strain rate impact test by itself, it showed a significant synergistic effect when combined with high molecular weight PB. Surprisingly, incorporation of just 10% of low molecular weight PB doubled the impact toughness of regular high impact PS (HIPS). It was observed that most of rubbery particles could initiate crazes. The effectiveness of low molecular weight PB in impact test was attributed to low strain rate deformation of each individual craze as a result of producing a large number of crazes in this material. In other words, high molecular weight PB chains make it possible to have an appropriate dispersion of rubbery phase in order to create a large number of crazes in the PS matrix and consequently decrease the velocity of each craze. Low molecular weight PB, in turn, would have enough time to locally plasticize craze fibrils and enhance the energy dissipation.

Keywords: molecular weight distribution, polystyrene, toughness, homopolymer

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148 Spray Drying and Physico-Chemical Microbiological Evaluation of Ethanolic Extracts of Propolis

Authors: David Guillermo Piedrahita Marquez, Hector Suarez Mahecha, Jairo Humberto Lopez

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The propolis are substances obtained from the beehive have an action against pathogens, prooxidant substances and free radicals because of its polyphenols content, this has motivated the use of these compounds in the food and pharmaceutical industries. However, due to their organoleptic properties and their ability to react with other compounds, their application has been limited; therefore, the objective of this research was to propose a mechanism to protect propolis and mitigate side effects granted by its components. To achieve the stated purpose ethanolic extracts of propolis (EEP) from three samples from Santander were obtained and their antioxidant and antimicrobial activity were evaluated in order to choose the extract with the biggest potential. Subsequently mixtures of the extract with maltodextrin were prepared by spray drying varying concentration and temperature, finally the yield, the physicochemical, and antioxidant properties of the products were measured. It was concluded that Socorro propolis was the best for the production of microencapsulated due to their activity against pathogenic strains, for its large percentage of DPPH radical inactivation and for its high phenolic content. In spray drying, the concentration of bioactive had a greater impact than temperature and the conditions set allowed a good performance and the production of particles with high antioxidant potential and little chance of proliferation of microorganisms. Also, it was concluded that the best conditions that allowed us to obtain the best particles were obtained after drying a mixture 1:2 ( EEP: Maltodextrin), besides the concentration is the most important variable in the spray drying process, at the end we obtained particles of different sizes and shape and the uniformity of the surface depend on the temperature. After watching the previously mentioned microparticles by scanning electron microscopy (SEM) it was concluded that most of the particles produced during the spray dry process had a spherical shape and presented agglomerations due to the moisture content of the ethanolic extracts of propolis (EEP), the morphology of the microparticles contributed to the stability of the final product and reduce the loss of total phenolic content.

Keywords: spray drying, propolis, maltodextrin, encapsulation, scanning electron microscopy

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147 In Silico Study of Cell Surface Structures of Parabacteroides distasonis Involved in Its Maintain Within the Gut Microbiota and Its Potential Pathogenicity

Authors: Jordan Chamarande, Lisiane Cunat, Corentine Alauzet, Catherine Cailliez-Grimal

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Gut microbiota (GM) is now considered a new organ mainly due to the microorganism’s specific biochemical interaction with its host. Although mechanisms underlying host-microbiota interactions are not fully described, it is now well-defined that cell surface molecules and structures of the GM play a key role in such relation. The study of surface structures of GM members is also fundamental for their role in the establishment of species in the versatile and competitive environment of the digestive tract and as a potential virulence factor. Among these structures are capsular polysaccharides (CPS), fimbriae, pili and lipopolysaccharides (LPS), all well-described for their central role in microorganism colonization and communication with host epithelium. The health-promoting Parabacteroides distasonis, which is part of the core microbiome, has recently received a lot of attention, showing beneficial properties for its host and as a new potential biotherapeutic product. However, to the best of the authors’ knowledge, the cell surface molecules and structures of P. distasonis that allow its maintain within the GM are not identified. Moreover, although P. distasonis is strongly recognized as intestinal commensal species with benefits for its host, it has also been recognized as an opportunistic pathogen. In this study, we reported gene clusters potentially involved in the synthesis of the capsule, fimbriae-like and pili-like cell surface structures in 26 P. distasonis genomes and applied the new RfbA-Typing classification in order to better understand and characterize the beneficial/pathogenic behaviour related to P. distasonis strains. In context, 2 different types of fimbriae, 3 of pilus and up to 14 capsular polysaccharide loci, have been identified over the 26 genomes studied. Moreover, the addition of data to the rfbA-Type classification modified the outcome by rearranging rfbA genes and adding a fifth group to the classification. In conclusion, the strain variability in terms of external proteinaceous structure could explain the inter-strain differences previously observed in P. distasonis adhesion capacities and its potential pathogenicity.

Keywords: gut microbiota, Parabacteroides distasonis, capsular polysaccharide, fimbriae, pilus, O-antigen, pathogenicity, probiotic, comparative genomics

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146 Characterisation of Extracellular Polymeric Substances from Bacteria Isolated from Acid Mine Decant in Gauteng, South Africa

Authors: Nonhlanhla Nkosi, Kulsum Kondiah

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The toxicological manifestation of heavy metals motivates interest towards the development of a reliable, eco-friendly biosorption process. With that being said, the aim of the current study was to characterise the EPS from heavy-metal resistant bacteria isolated from acid mine decant on the West Rand, Gauteng, South Africa. To achieve this, six exopolysaccharide (EPS) producing, metal resistant strains (Pb101, Pb102, Pb103, Pb204, Co101, and Ni101) were identified as Bacillus safensis strain NBRC 100820, Bacillus proteolyticus, Micrococcus luteus, Enterobacter sp. Pb204, Bacillus wiedmannii and Bacillus zhangzhouensis, respectively with 16S rRNA sequencing. Thereafter, EPS was extracted using chemical (formaldehyde/NaOH) and physical (ultrasonification) methods followed by physicochemical characterisation of carbohydrate, DNA, and protein contents using chemical assays and spectroscopy (FTIR- Fourier transformed infrared and 3DEEM- three-dimensional excitation-emission matrix fluorescence spectroscopy). EPS treated with formaldehyde/NaOH showed better recovery of macromolecules than ultrasonification. The results of the present study showed that carbohydrates were more abundant than proteins, with carbohydrate and protein concentrations of 8.00 mg/ml and 0.22 mg/ml using chemical method in contrast to 5.00 mg/ml and 0.77 mg/ml using physical method, respectively. The FTIR spectroscopy results revealed that the extracted EPS contained hydroxyl, amide, acyl, and carboxyl groups that corresponded to the aforementioned chemical analysis results, thus asserting the presence of carbohydrates, DNA, polysaccharides, and proteins in the EPS. These findings suggest that identified functional groups of EPS form surface charges, which serve as the binding sites for suspended particles, thus possibly mediating adsorption of divalent cations and heavy metals. Using the extracted EPS in the development of a cost-effective biosorption solution for industrial wastewater treatment is attainable.

Keywords: biosorbent, exopolysaccharides, heavy metals, wastewater treatment

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145 Synergistic Effect of Plant Growth Promoting Bacteria and Arbuscular Mycorrhizal Fungi to Enhance Wheat Grain Yield, Biofortification and Soil Health: A Field Study

Authors: Radheshyam Yadav, Ramakrishna Wusirika

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Plant Growth Promoting Bacteria (PGPB) and Arbuscular Mycorrhizal (AM) Fungi are ubiquitous in soil and often very critical for crop yield and agriculture sustainability, and this has motivated the agricultural practices to support and promote PGPB and AM Fungi in agriculture. PGPB can be involved in a range of processes that affect Nitrogen (N) and Phosphorus (P) transformations in soil and thus influence nutrient availability and uptake to the plants. A field study with two wheat cultivars, HD-3086, and HD-2967 was performed in Malwa region, Bathinda of Punjab, India, to evaluate the effect of native and non-native PGPB alone and in combination with AM fungi as an inoculant on wheat grain yield, nutrient uptake and soil health parameters (dehydrogenase, urease, β‐glucosidase). Our results showed that despite an early insignificant increase in shoot length, plants treated with PGPB (Bacillus sp.) and AM Fungi led to a significant increase in shoot growth at maturity, aboveground biomass, nitrogen (45% - 40%) and phosphorus (40% - 34%) content in wheat grains relative to untreated control plants. Similarly, enhanced grain yield and nutrients uptake i.e. copper (27.15% - 36.25%) iron (43% - 53%) and zinc (44% - 47%) was recorded in PGPB and AM Fungi treated plants relative to untreated control. Overall, inoculation with native PGPB alone and in combination with AM Fungi provided benefits to enhance grain yield, wheat biofortification, and improved soil fertility, despite this effect varied depending on different PGPB isolates and wheat cultivars. These field study results provide evidence of the benefits of agricultural practices involving native PGPB and AM Fungi to the plants. These native strains and AM Fungi increased accumulations of copper, iron, and zinc in wheat grains, enhanced grain yield, and soil fertility.

Keywords: AM Fungi, biofortification, PGPB, soil microbial enzymes

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144 Characterization and Optimization of Culture Conditions for Sulphur Oxidizing Bacteria after Isolation from Rhizospheric Mustard Soil, Decomposing Sites and Pit House

Authors: Suman Chaudhary, Rinku Dhanker, Tanvi, Sneh Goyal

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Sulphur oxidizing bacteria (SOB) have marked their significant role in perspectives of maintaining healthy environment as researchers from all over the world tested and apply these in waste water treatment plants, bioleaching of heavy metals, deterioration of bridge structures, concrete and for bioremediation purposes, etc. Also, these SOB are well adapted in all kinds of environment ranging from normal soil, water habitats to extreme natural sources like geothermal areas, volcanic eruptions, black shale and acid rock drainage (ARD). SOB have been isolated from low pH environment of anthropogenic origin like acid mine drainage (AMD) and bioleaching heaps, hence these can work efficiently in different environmental conditions. Besides having many applications in field of environment science, they may be proven to be very beneficial in area of agriculture as sulphur is the fourth major macronutrients required for the growth of plants. More amount of sulphur is needed by pulses and oilseed crops with respect to the cereal grains. Due to continuous use of land for overproduction of more demanding sulphur utilizing crops and without application of sulphur fertilizers, its concentration is decreasing day by day, and thus, sulphur deficiency is becoming a great problem as it affects the crop productivity and quality. Sulphur is generally found in soils in many forms which are unavailable for plants (cannot be use by plants) like elemental sulphur, thiosulphate which can be taken up by bacteria and converted into simpler forms usable by plants by undergoing a series of transformations. So, keeping the importance of sulphur in view for various soil types, oilseed crops and role of microorganisms in making them available to plants, we made an effort to isolate, optimize, and characterize SOB. Three potential strains of bacteria were isolated, namely SSF7, SSA21, and SSS6, showing sulphate production of concentration, i.e. 2.268, 3.102, and 2.785 mM, respectively. Also, these were optimized for various culture conditions like carbon, nitrogen source, pH, temperature, and incubation time, and characterization was also done.

Keywords: sulphur oxidizing bacteria, isolation, optimization, characterization, sulphate production

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143 Comparative Functional Analysis of Two Major Sterol-Biosynthesis Regulating Transcription Factors, Hob1 and Sre1, in Pathogenic Cryptococcus Species Complex

Authors: Dong-Gi Lee, Suyeon Cha, Yong-Sun Bahn

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Sterol lipid is essential for cell membrane structure in eukaryotic cells. In mammalian cells, sterol regulatory element binding proteins (SREBPs) act as principal regulators of cellular cholesterol which is essential for proper cell membrane fluidity and structure. SREBP and sterol regulation are related to levels of cellular oxygen because it is a major substrate for sterol synthesis. Upon cellular sterol and oxygen levels are depleted, SREBP is translocated to the Golgi where it undergoes proteolytic cleavage of N terminus, then it travels to the nucleus to play a role as transcription factor. In yeast cells, synthesis of ergosterol is also highly oxygen consumptive, and Sre1 is a transcription factor known to play a central role in adaptation to growth under low oxygen condition and sterol homeostasis in Cryptococcus neoformans. In this study, we observed phenotypes in other strains of Cryptococcus species by constructing hob1Δ and sre1Δ mutants to confirm whether the functions of both genes are conserved in most serotypes. As a result, hob1Δ showed no noticeable phenotype under treatment of antifungal drugs and most environmental stresses in R265 (C. gattii) and XL280 (C. neoformans), suggesting that Hob1 is related to sterol regulation only in H99 (serotype A). On the other hand, the function of Sre1 was found to be conserved in most serotypes. Furthermore, mating experiment of hob1Δ or sre1Δ showed dramatic defects in serotype A (H99) and D (XL280). It revealed that Hob1 and Sre1 related to mating ability in Cryptococcus species, especially cell fusion efficiency. In conclusion, HOB1 and SRE1 play crucial role in regulating sterol-homeostasis and differentiation in C. neoformans, moreover, Hob1 is specific gene in Cryptococcus neoformans. It suggests that Hob1 is considered as potent factor-targeted new safety antifungal drug.

Keywords: cryptococcus neoformans, Hob1, Sre1, sterol regulatory element binding proteins

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142 An Attenuated Quadruple Gene Mutant of Mycobacterium tuberculosis Imparts Protection against Tuberculosis in Guinea Pigs

Authors: Shubhita Mathur, Ritika Kar Bahal, Priyanka Chauhan, Anil K. Tyagi

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Mycobacterium tuberculosis, the causative agent of human tuberculosis, is a major cause of mortality. Bacillus Calmette-Guérin (BCG), the only licensed vaccine available for protection against tuberculosis confers highly variable protection ranging from 0%-80%. Thus, novel vaccine strains need to be evaluated for their potential as a vaccine against tuberculosis. We had previously constructed a triple gene mutant of M. tuberculosis (MtbΔmms), having deletions in genes encoding for phosphatases mptpA, mptpB, and sapM that are involved in host-pathogen interaction. Though vaccination with Mtb∆mms strain induced protection in the lungs of guinea pigs, the mutant strain was not able to control the hematogenous spread of the challenge strain to the spleens. Additionally, inoculation with Mtb∆mms resulted in some pathological damage to the spleens in the early phase of infection. In order to overcome the pathology caused by MtbΔmms in the spleens of guinea pigs and also to control the dissemination of the challenge strain, MtbΔmms was genetically modified by disrupting bioA gene to generate MtbΔmmsb strain. Further, in vivo attenuation of MtbΔmmsb was evaluated, and its protective efficacy was assessed against virulent M. tuberculosis challenge in guinea pigs. Our study demonstrates that Mtb∆mmsb mutant was highly attenuated for growth and virulence in guinea pigs. Vaccination with Mtb∆mmsb mutant generated significant protection in comparison to sham-immunized animals at 4 and 12 weeks post-infection in lungs and spleens of the infected animals. Our findings provide evidence that deletion of genes involved in signal transduction and biotin biosynthesis severely attenuates the pathogen and the single immunization with the auxotroph was able to provide significant protection as compared to sham-immunized animals. The protection imparted by Mtb∆mmsb fell short in comparison to the protection observed in BCG-immunized animals. This study nevertheless indicates the importance of attenuated multiple gene deletion mutants of M. tuberculosis in generating protection against tuberculosis.

Keywords: Mycobacterium tuberculosis, BCG, MtbΔmmsb, bioA, guinea pigs

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