Search results for: Escherichia coli bacteria
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1802

Search results for: Escherichia coli bacteria

1562 Focus on the Bactericidal Efficacies of Alkaline Agents in Solid and the Required Time for Bacterial Inactivation

Authors: Hakimullah Hakim, Chiharu Toyofuku, Mari Ota, Mayuko Suzuki, Miyuki Komura, Masashi Yamada, Md. Shahin Alam, Natthanan Sangsriratanakul, Dany Shoham, Kazuaki Takehara

Abstract:

Disinfectants and their application are essential part of infection control strategies and enhancement of biosecurity at farms, worldwide. Alkaline agents are well known for their strong and long term antimicrobial capacities and most frequently are applied at farms for control and prevention of biological hazards. However, inadequate information regarding such materials’ capacities to inactivate pathogens and their improper applications fail farmers to achieve the mentioned goal. Thus, this requires attention to further evaluate their efficacies, under different conditions and in different ways. Here in this study we evaluated bactericidal efficacies of food additive grade of calcium hydroxide (FdCa(OH)2) powder derived from natural calcium carbonates obtained from limestone (Fine Co., Ltd., Tokyo, Japan), and bioceramic powder (BCX) derived from chicken feces at pH 13 (NMG environmental development Co., Ltd., Tokyo, Japan), for their efficacies to inactivate bacteria in feces. [Materials & Methods] Chicken feces were inoculated by 100 µl Escherichia coli and Salmonella Infantis in falcon tubes, individually, then FdCa(OH)2 or BCX powders were individually added to make final concentration of 0, 5, 10, 20 and 30% (w/w) in total weight of 0.5g, followed by properly mixing and incubating at room temperature for certain periods of time, in a dark place. Afterwards, 10 ml 1M Tris-HCl (pH 7.2) was added onto them to reduce their pH, in order to stop powders’ activities and to harvest the remained viable bacteria, whereas using normal medium or dW2 to recover bacteria increases the mixture pH, and as a result bacteria would be inactivated soon; therefore, the latter practice brings about incorrect and misleading results. Samples were then inoculated on DHL agar plates in order to calculate colony forming units (CFU)/ml of viable bacteria. [Results and Discussion] FdCa(OH)2 powder at 10% and 5% required 3 hr and 6 hr exposure times, respectively, while BCX powder at 20% concentrations required 6 hr exposure time to kill the mentioned bacteria in feces down to lower than detectable level (≤ 3.6 log10 CFU/ml). This study confirmed capacities of FdCa(OH)2 and BCX powders to inactivate bacteria in feces, and both materials are environment friendly materials, with no risk to human or animal’s health. This finding helps farmers to properly apply alkaline agents in appropriate concentrations and exposure times in their farms, in order to prevent and control infectious diseases outbreaks and to enhance biosecurity. Finally, this finding may help farmers to implement better strategies for infections control in their livestock farms.

Keywords: bacterial inactivation, bioceramic, biosecurity at livestock farms, chicken feces

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1561 Docking Studie of Biologically Active Molecules: Exploring Medical Applications

Authors: Sihame Amakrane, Zineb Ouahdi, Mohammed Salah, Said Belaaouad

Abstract:

\This research explores the efficacy of novel pyrimidine derivatives on bacterial strains such as Escherichia coli, Staphylococcus aureus, and Myccobacterium tuberculosis, utilizing bending energy calculations. Of the 25 compounds examined, 13 displayed potent activity against all the bacterial strains under study, exhibiting bending energy measurements between -7.4 and -10.7 kcal/mol. The -7.4 kcal/mol value corresponds to the bending energy of the SA12 and SA13 compounds with the 2xct protein (Staphylococcus aureus), whereas the -10.7 kcal/molis linked with the bending energy of SA6 and SA11 compounds with the 6GAV protein (Myccobacterium tuberculosis). Further research will involve a QSAR (Quantitative Structure-Activity Relationship) study aimed at constructing a reliable model to combat the aforementioned bacterial strains and a molecular dynamics study to evaluate the stability of ligand-protein complexes.

Keywords: docking, QSAR, bending energy, e. coli

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1560 Evaluation of Antimicrobial Activity of Different Dithiolethiones

Authors: Zehour Rahmani, Messouda Dekmouche, Mohamed Hadjadj, Mokhtar Saidi

Abstract:

In the last decades of the nineteenth century, the study of disease – causing microorganisms became concentrated on bacteria and largely institutionalized. In earlier years, the scientists interested in bacteria had originally been chemists like Pasteur, physicists like Tyndall, or botanists like Cohn and ward. For this reason, the objective of this research was to evaluate the potential of some dithiolethiones on standard microorganism strains as well as multi-drug resistant bacteria, which were isolated from hospitals. Recent studies have demonstrated, that several dithiolethione compounds, particularly (3H-1,2-dithiole-3-thione), exhibit the biological activities against several bacteria.

Keywords: bacteria, dithiolethiones, microorganism, potential

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1559 Prevalence of Antibiotic-Resistant Bacteria Isolated from Fresh Vegetables Retailed in Eastern Spain

Authors: Miguel García-Ferrús, Yolanda Domínguez, M Angeles Castillo, M Antonia Ferrús, Ana Jiménez-Belenguer

Abstract:

Antibiotic resistance is a growing public health concern worldwide, and it is now regarded as a critical issue within the "One Health" approach that affects human and animal health, agriculture, and environmental waste management. This concept focuses on the interconnected nature of human, animal and environmental health, and WHO highlights zoonotic diseases, food safety, and antimicrobial resistance as three particularly relevant areas for this framework. Fresh vegetables are garnering attention in the food chain due to the presence of pathogens and because they can act as a reservoir for Antibiotic Resistance Bacteria (ARB) and Antibiotic Resistance Genes (ARG). These fresh products are frequently consumed raw, thereby contributing to the spread and transmission of antibiotic resistance. Therefore, the aim of this research was to study the microbiological quality, the prevalence of ARB, and their role in the dissemination of ARG in fresh vegetables intended for human consumption. For this purpose, 102 samples of fresh vegetables (30 lettuce, 30 cabbage, 18 strawberries and 24 spinach) from different retail establishments in Valencia (Spain) have been analyzed to determine their microbiological quality and their role in spreading ARB and ARG. The samples were collected and examined according to standardized methods for total viable bacteria, coliforms, Shiga toxin-producing Escherichia coli (STEC), Listeria monocytogenes and Salmonella spp. Isolation was made in culture media supplemented with antibiotics (cefotaxime and meropenem). A total of 239 strains resistant to beta-lactam antibiotics (Third-Generation Cephalosporins and Carbapenems) were isolated. Thirty Gram-negative isolates were selected and biochemically identified or partial sequencing of 16S rDNA. Their sensitivity to 12 antibiotic discs was determined using the Kirby-Bauer disc diffusion technique to different therapeutic groups. To determine the presence of ARG, PCR assays for the direct sample and selected isolate DNA were performed for main expanded spectrum beta-lactamase (ESBL)-, carbapenemase-encoding genes and plasmid-mediated quinolone resistance genes. From the total samples, 68% (24/24 spinach, 28/30 lettuce and 17/30 cabbage) showed total viable bacteria levels over the accepted standard 10(2)-10(5) cfu/g range; and 48% (24/24 spinach, 19/30 lettuce and 6/30) showed coliforms levels over the accepted standard 10(2)-10(4) cfu/g range. In 9 samples (3/24 spinach, 3/30 lettuce, 3/30 cabbage; 9/102 (9%)) E. coli levels were higher than the standard 10(3) cfu/g limit. Listeria monocytogenes, Salmonella and STEC have not been detected. Six different bacteria species were isolated from samples. Stenotrophomonas maltophilia (64%) was the prevalent species, followed by Acinetobacter pitii (14%) and Burkholderia cepacia (7%). All the isolates were resistant to at least one tested antibiotic, including meropenem (85%) and ceftazidime (46%). Of the total isolates, 86% were multidrug-resistant and 68% were ESBL productors. Results of PCR showed the presence of resistance genes to beta-lactams blaTEM (4%) and blaCMY-2 (4%), to carbapenemes blaOXA-48 (25%), blaVIM (7%), blaIMP (21%) and blaKPC (32%), and to quinolones QnrA (7%), QnrB (11%) and QnrS (18%). Thus, fresh vegetables harboring ARB and ARG constitute a potential risk to consumers. Further studies must be done to detect ARG and how they propagate in non-medical environments.

Keywords: ESBL, β-lactams, resistances, fresh vegetables.

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1558 Antimicrobial Activity of Eucalyptus globulus Essential Oil: Disc Diffusion versus Vapour Diffusion Methods

Authors: Boukhatem Mohamed Nadjib, Ferhat Mohamed Amine

Abstract:

Essential Oils (EO) produced by medicinal plants have been traditionally used for respiratory tract infections and are used nowadays as ethical medicines for colds. The aim of this study was to test the efficacy of the Algerian EGEO against some respiratory tract pathogens by disc diffusion and vapour diffusion methods at different concentrations. The chemical composition of the EGEO was analysed by Gas Chromatography-Mass Spectrometry. Fresh leaves of E. globulus on steam distillation yielded 0.96% (v/w) of essential oil whereas the analysis resulted in the identification of a total of 11 constituents, 1.8 cineole (85.8%), α-pinene (7.2%) and β-myrcene (1.5%) being the main components. By disc diffusion method, EGEO showed potent antimicrobial activity against Gram-positive more than Gram-negative bacteria. The Diameter of Inhibition Zone (DIZ) varied from 69 mm to 75 mm for Staphylococcus aureus and Bacillus subtilis (Gram +) and from 13 to 42 mm for Enterobacter sp and Escherichia coli (Gram-), respectively. However, the results obtained by both agar diffusion and vapour diffusion methods were different. Significantly higher antibacterial activity was observed in the vapour phase at lower concentrations. A. baumanii and Klebsiella pneumoniae were the most susceptible strains to the oil vapour with DIZ varied from 38 to 42 mm. Therefore, smaller doses of EO in the vapour phase can be inhibitory to pathogenic bacteria. Else, the DIZ increased with increase in the concentration of the oil. There is growing evidence that EGEO in the vapour phase are effective antibacterial systems and appears worthy to be considered for practical uses in the treatment or prevention of patients with respiratory tract infections or as air decontaminants in the hospital. The present study indicates that EGEO has considerable antimicrobial activity, deserving further investigation for clinical applications.

Keywords: eucalyptus globulus, essential oils, respiratory tract pathogens, antimicrobial activity, vapour phase

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1557 Green Synthesis of Silver Nanoparticles from Citrus aurantium Aqueous Pollen Extract and Their Antibacterial Activity

Authors: Mohammad Ali Karimi, Hossein Tavallali, Abdolhamid Hatefi-Mehrjardi

Abstract:

Pollen extract of in vitro plants raised of Citrus aurantium as reducer and stabilizer was assessed for the green synthesis of silver nanoparticles (AgNPs). The synthesis of AgNPs was performed at room temperature assisting in solutions by reduction takes place rapidly for 10 min. Surface plasmon resonance (SPR) peaks in UV–Vis spectra indicated the formation of polydispersive AgNPs. Silver ions concentration, pH, temperature and reaction time were optimized in the synthesis of AgNPs. The nanoparticles obtained were characterized by UV-Vis spectrophotometer, transmission electron microscopy (TEM). X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy techniques. The synthesized AgNPs were mostly spherical in shape with an average size of 15 nm. XRD study shows that the AgNPs are crystalline in nature with face-centered cubic (fcc) geometry. It shows the significant antibacterial efficacy against Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli) by disk diffusion method using Mueller-Hinton Agar.

Keywords: green synthesis, Citrus aurantium, silver nanoparticles, antibacterial activity

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1556 Antimicrobial Activity of Fatty Acid Salts against Microbes for Food Safety

Authors: Aya Tanaka, Mariko Era, Manami Masuda, Yui Okuno, Takayoshi Kawahara, Takahide Kanyama, Hiroshi Morita

Abstract:

Objectives— Fungi and bacteria are present in a wide range of natural environments. They are breed in the foods such as vegetables and fruit, causing corruption and deterioration of these foods in some cases. Furthermore, some species of fungi and bacteria are known to cause food intoxication or allergic reactions in some individuals. To prevent fungal and bacterial contamination, various fungicides and bactericidal have been developed that inhibit fungal and bacterial growth. Fungicides and bactericides must show high antifungal and antibacterial activity, sustainable activity, and a high degree of safety. Therefore, we focused on the fatty acid salt which is the main component of soap. We focused on especially C10K and C12K. This study aimed to find the effectiveness of the fatty acid salt as antimicrobial agents for food safety. Materials and Methods— Cladosporium cladosporioides NBRC 30314, Penicillium pinophilum NBRC 6345, Aspergillus oryzae (Akita Konno store), Rhizopus oryzae NBRC 4716, Fusarium oxysporum NBRC 31631, Escherichia coli NBRC 3972, Bacillus subtilis NBRC 3335, Staphylococcus aureus NBRC 12732, Pseudomonas aenuginosa NBRC 13275 and Serratia marcescens NBRC 102204 were chosen as tested fungi and bacteria. Hartmannella vermiformis NBRC 50599 and Acanthamoeba castellanii NBRC 30010 were chosen as tested amoeba. Nine fatty acid salts including potassium caprate (C10K) and laurate (C12K) at 350 mM and pH 10.5 were used as antifungal activity. The spore suspension of each fungus (3.0×10⁴ spores/mL) or the bacterial suspension (3.0×10⁵ or 3.0×10⁶ or 3.0×10⁷ CFU/mL) was mixed with each of the fatty acid salts (final concentration of 175 mM). Samples were counted at 0, 10, 60, and 180 min by plating (100 µL) on potato dextrose agar or nutrient agar. Fungal and bacterial colonies were counted after incubation for 1 or 2 days at 30 °C. Results— C10K was antifungal activity of 4 log-unit incubated time for 10 min against fungi other than A. oryzae. C12K was antifungal activity of 4 log-unit incubated time for 10 min against fungi other than P. pinophilum and A. oryzae. C10K and C12K did not show high anti-yeast activity. C10K was antibacterial activity of 6 or 7 log-unit incubated time for 10 min against bacteria other than B. subtilis. C12K was antibacterial activity of 5 to 7 log-unit incubated time for 10 min against bacteria other than S. marcescens. C12K was anti-amoeba activity of 4 log-unit incubated time for 10 min against H. vermiformis. These results suggest C10K and C12K have potential in the field of food safety.

Keywords: food safety, microbes, antimicrobial, fatty acid salts

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1555 Photocatalytic Eco-Active Ceramic Slabs to Abate Air Pollution under LED Light

Authors: Claudia L. Bianchi, Giuseppina Cerrato, Federico Galli, Federica Minozzi, Valentino Capucci

Abstract:

At the beginning of the industrial productions, porcelain gres tiles were considered as just a technical material, aesthetically not very beautiful. Today thanks to new industrial production methods, both properties, and beauty of these materials completely fit the market requests. In particular, the possibility to prepare slabs of large sizes is the new frontier of building materials. Beside these noteworthy architectural features, new surface properties have been introduced in the last generation of these materials. In particular, deposition of TiO₂ transforms the traditional ceramic into a photocatalytic eco-active material able to reduce polluting molecules present in air and water, to eliminate bacteria and to reduce the surface dirt thanks to the self-cleaning property. The problem of photocatalytic materials resides in the fact that it is necessary a UV light source to activate the oxidation processes on the surface of the material, processes that are turned off inexorably when the material is illuminated by LED lights and, even more so, when we are in darkness. First, it was necessary a thorough study change the existing plants to deposit the photocatalyst very evenly and this has been done thanks to the advent of digital printing and the development of an ink custom-made that stabilizes the powdered TiO₂ in its formulation. In addition, the commercial TiO₂, which is used for the traditional photocatalytic coating, has been doped with metals in order to activate it even in the visible region and thus in the presence of sunlight or LED. Thanks to this active coating, ceramic slabs are able to purify air eliminating odors and VOCs, and also can be cleaned with very soft detergents due to the self-cleaning properties given by the TiO₂ present at the ceramic surface. Moreover, the presence of dopant metals (patent WO2016157155) also allows the material to work as well as antibacterial in the dark, by eliminating one of the negative features of photocatalytic building materials that have so far limited its use on a large scale. Considering that we are constantly in contact with bacteria, some of which are dangerous for health. Active tiles are 99,99% efficient on all bacteria, from the most common such as Escherichia coli to the most dangerous such as Staphilococcus aureus Methicillin-resistant (MRSA). DIGITALIFE project LIFE13 ENV/IT/000140 – award for best project of October 2017.

Keywords: Ag-doped microsized TiO₂, eco-active ceramic, photocatalysis, digital coating

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1554 Investigating the Antibacterial Properties and Omega-3 Levels of Evening Primrose Plant Against Multi-Drug Resistant Bacteria

Authors: A. H. Taghdisi, M. Mirmohammadi, S. Kamali

Abstract:

Evening primrose (Oenothera biennis L.) is a biennial and herbaceous and one of the most important species of medicinal plants in the world. due to the production of unsaturated fatty acids such as linoleic acid, alpha-linolenic acid, etc. in its seeds and roots, and compounds such as kaempferol in its leaves, Evening primrose has important medicinal efficiency such as reducing premenstrual problems, acceleration of wound healing, inhibiting platelet aggregation, sedation of cardiovascular diseases, and treatment of viral infections. The sap of the plant is used to treat warts, and the plant itself is used as a charm against mental and spiritual diseases and poisonous animals. Its leaves have significant antibacterial activity against yellow staphylococci. It is also used in the treatment of poisoning, especially the toxication caused by the consumption of alcoholic beverages, in the treatment of arteriosclerosis and diseases caused by liver cell insufficiency. Low germination and production speed are the problems of evening primrose growth and propagation. In the present study, extracts were obtained from four components (flowers, stems, seeds, leaves) of the evening primrose plant using the Soxhlet apparatus. To measure the antibacterial properties against MDR bacteria, microbial methods, including dilution, cultivation on a plate containing nutrient agar culture medium, and disc diffusion in agar, were performed using Staphylococcus aureus and Escherichia coli bacteria on all four extracts. The maximum antibacterial activity related to the dilution method was obtained in all extracts. In the plate culture method, antibacterial activity was obtained for all extracts in the nutrient agar medium. The maximum diameter of the non-growth halo was obtained in the disc diffusion method in agar in the leaf extract. The statistical analysis of the microbial part was done by one-way ANOVA test (SPSS). By comparing the amount of omega-3 in extracts of Iranian and foreign oils available in the market and the extracts extracted from evening primrose plant samples with gas chromatography, it is shown that the stem extract had the most omega-3 (oleic acid) and compared to the extract of the mentioned oils, it had the highest amount of omega-3 overall. Also, the amount of omega-3 in the extract of Iranian oils was much higher than in the extract of foreign oils. It should be noted that the extract of foreign oils had a more complete composition of omega-3 than the extract of Iranian oils.

Keywords: antibacterial activity, MDR bacteria, evening primrose, omega-3

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1553 Effect of Cellulase Pretreatment for n-Hexane Extraction of Oil from Garden Cress Seeds

Authors: Boutemak Khalida, Dahmani Siham

Abstract:

Garden cress (Lepidium Sativum L.) belonging to the family Brassicaceae, is edible growing annual herb. Its various parts (roots, leaves and seeds) have been used to treat various human ailments. Its seed extracts have been screened for various biological activities like hypotensive, antimicrobial, bronchodilator, hypoglycaemic and antianemic. The aim of the present study is to optimize the process parameters (cellulase concentration and incubation time) of enzymatic pre-treatment of the garden cress seeds and to evaluate the effect of cellulase pre-treatment of the crushed seeds on the oil yield, physico-chemical properties and antibacterial activity and comparing to non-enzymatic method. The optimum parameters of cellulase pre-treatment were as follows: cellulase of 0,1% w/w and incubation time of 2h. After enzymatic pre-treatment, the oil was extracted by n-hexane for 1.5 h, the oil yield was 4,01% for cellulase pre-treatment as against 10,99% in the control sample. The decrease in yield might be caused a result of mucilage. Garden cress seeds are covered with a layer of mucilage which gels on contact with water. At the same time, the antibacterial activity was carried out using agar diffusion method against 4 food-borne pathogens (Escherichia coli, Salmonella typhi,Staphylococcus aureus, Bacillus subtilis). The results showed that bacterial strains are very sensitive to the oil with cellulase pre-treatment. Staphylococcus aureus is extremely sensitive with the largest zone of inhibition (40 mm), Escherichia coli and salmonella typhi had a very sensitive to the oil with a zone of inhibition (26 mm). Bacillus subtilizes is averagely sensitive which gave an inhibition of 16 mm. But it does not exhibit sensivity to the oil without enzymatic pre-treatment with a zone inhibition (< 8 mm). Enzymatic pre-treatment could be useful for antimicrobial activity of the oil, and hold a good potential for use in food and pharmaceutical industries.

Keywords: Lepidium sativum L., cellulase, enzymatic pretreatment, antibacterial activity.

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1552 Trends in the Incidence of Bloodstream Infections in Patients with Hematological Malignancies in the Period 1991–2012

Authors: V. N. Chebotkevich, E. E. Schetinkina, V. V. Burylev, E. I. Kaytandzhan, N. P. Stizhak

Abstract:

Objective: Blood stream infections (BSI) are severe, life-threatening illness for immuno compromised patients with hematological malignancies. We report the trend in blood-stream infections in this group of patients in the period 1991-2013. Methods: A total of 4742 blood samples investigated. All blood cultures were incubated in a continuous monitoring system for 7 days before discarding negative. On signaled positive, organism was identified by conventional methods. The Real-time polymerase chain reaction (PCR) was used for the indication of human herpes virus 6 (HHV-6), Cytomegalovirus (CMV) and Epstein-Barr virus (EBV). Results: Between 1991 and 2001 the incidence of Gram-positive bacteria (Staphylococcus epidermidis, Staphylococcus aureus) being the most common germs isolated (70,9%) were as Gram-negative rods (Escherichia coli, Klebsiella spp., Pseudomonas spp.) – 29,1%. In next decade 2002-2012 the number of Gram-negative bacteria was increased up to 40.2%. It is shown that the incidence of bacteremia was significantly more frequent at the background of detectable Cytomegalovirus and Epstein-Barr virus-specific DNA in blood. Over recent years, an increased frequency of micro mycetes was registered in blood of the patients with hematological malignancies (Candida spp. was predominant). Conclusion: Accurate and timely detection of BSI is important in determining appropriate treatment of infectious complications in patients with hematological malignancies. The isolation of Staphylococcus epidermidis from blood cultures remains a clinical dilemma for physicians and microbiologists. But in many cases this agent is of the clinical significance in immunocompromised patients with hematological malignancies. The role of CMV and EBV in development of bacteremia was demonstrated.

Keywords: infectious complications, blood stream infections, bacteremia, hemoblastosis

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1551 Production of Biotechnological Chondroitin from Recombinant E, Coli K4 Strains on Renewable Substrates

Authors: Donatella Cimini, Sergio D’ambrosio, Saba Sadiq, Chiara Schiraldi

Abstract:

Chondroitin sulfate (CS), as well as modified CS, and unsulfated chondroitin, are largely applied in research today. CS is a linear glycosaminoglycan normally present in cartilage-rich tissues and bones in the form of proteoglycans decorated with sulfate groups in different positions. CS is used as an effective non-pharmacological alternative for the treatment of osteoarthritis, and other potential applications in the biomedical field are being investigated. Some bacteria, such as E. coli K4, produce a polysaccharide that is a precursor of CS (unsulfated chondroitin). This work focused on the construction of integrative E. coli K4 recombinant strains overexpressing genes (kfoA, kfoF, pgm and galU in different combinations) involved in the biosynthesis of the nucleotide sugars necessary for polysaccharide synthesis. Strain growth and polymer production were evaluated using renewable waste materials as substrates in shake flasks and small-scale batch fermentation processes. Results demonstrated the potential to replace pure sugars with cheaper medium components to establish environmentally sustainable and cost-effective production routes for potential industrial development. In fact, although excellent fermentation results have been described so far by employing strains that naturally produce chondroitin-like polysaccharides on semi-defined media, there is still the need to reduce manufacturing costs by providing a cost-effective biotechnological alternative to currently used animal-based extraction procedures.

Keywords: E. coli K4, chondroitin, microbial cell factories, glycosaminoglycans, renewable resources

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1550 Assessment of Microbiological Status of Branded and Street Vended Ice-Cream Offered for Public Consumption: A Comparative Study in Tangail Municipality, Bangladesh

Authors: Afroza Khatun, Masuma, Md. Younus Mia, Kamal Kanta Das

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Analysis of the microbial status and physicochemical parameters of some branded and street vended ice cream showed that total viable bacteria in branded ice cream ranged from 4.8×10³ to 1.10×10⁵ cfu/ml, and in street vended ice-cream ranged from 7.5×10⁴ to 1.6×10⁸ cfu/ml. Total coliform bacteria present up to 9.20×10³ cfu/ml in branded ice cream and 5.3×10³ to 9.6×10⁶ cfu/ml observed in street vended ice cream. Total E. coli were found to be present within a range from 0 to 4.5×10³ cfu/ml in branded and 4.1×10² to 7.5×10⁴ cfu/ml in street ice cream. The ranges of Staphylococcus aureus count were 1.8×10² to 2.9×10⁴ cfu/ml (branded) and 3.9×10⁴ to 7.9×10⁶ cfu/ml (street). The pH of both types of ice cream showed acidic to neutral conditions where the concentration of pH for branded ice cream was 5.5 to 6.9, as well as the value of pH in street ice cream, was 6.2 to 7.0. The range of Total soluble solids in several branded ice creams was 26 to 29%, and the value of TSS obtained in street-vended ice-creams ranged from 5 to 10%. The overall results of this research demonstrated that the microbial quality in all street ice creams exceeded the BSTI standard and exhibited lower quality than the industrially produced branded ice creams due to comparatively faulty manufacturing processes and poor hygiene practices. The presence of pathogenic microbes was also observed in branded ice creams which was quite alarming for public health. So it is suggested that the government authorized organization should conduct the proper monitoring system to ensure that both branded and street vended ice-creams are microbiologically safe to prevent public health hazards.

Keywords: food safety, microbiological analysis, physicochemical, ice-cream, E. coli, Staphylococcus aureus

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1549 Dynamics of Bacterial Contamination and Oral Health Risks Associated with Currency Notes and Coins Circulating in Kampala City

Authors: Abdul Walusansa

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In this paper, paper notes and coins were collected from general public in Kampala City where ready-to-eat food can be served, in order to survey for bacterial contamination. The total bacterial number and potentially pathogenic organisms loading on currency were tested. All isolated potential pathogens were also tested for antibiotic resistance against four most commonly prescribed antibiotics. 1. The bacterial counts on one hundred paper notes sample were ranging between 6~10918/cm cm-2,the median was 141/ cm-2, according to the data it was much higher than credit cards and Australian notes which were made of polymer. The bacterial counts on sixty coin samples were ranging between 2~380/cm-2, much less than paper notes. 2. Coliform (65.6%), E. coli (45.9%), S. aureus (41.7%), B. cereus (67.7%), Salmonella (19.8%) were isolated on one hundred paper notes. Coliform (22.4%), E. coli (5.2%), S. aureus (24.1%), B. cereus (34.5%), Salmonella (10.3%) were isolated from sixty coin samples. These results suggested a high rate of potential pathogens contamination of paper notes than coins. 3. Antibiotic resistances are commonly in most of the pathogens isolated on currency. Ampicillin resistance was found in 60%of Staphylococcus aureus isolated on currency, as well as 76.6% of E. coil and 40% of Salmonella. Erythromycin resistance was detected in 56.6% of S. aureus and in 80.0% of E. coli. All the pathogens isolated were sensitive to Norfloxacin, Salmonella and S. aureus also sensitive to Cefaclor. In this paper, we also studied the antimicrobial capability of metal coins, coins collected from different countries were tested for the ability to inhibit the growth of E. sakazakii, S. aureus, E. coli, L. monocytogenes and S. typhimurium. 1) E. sakazakii appeared very sensitive to metal coins, the second is S. aureus, but E. coli, L. monocytogenes and S. typhimurium are more resistant to these metal coin samples. 2) Coins made of Nickel-brass alloy and Copper-nickel alloy showed a better effect in anti-microbe than other metal coins, especially the ability to inhibited the growth of E. sakazakii and S. aureus, all the inhibition zones produced on nutrient agar are more than 20.6 mm. Aluminium-bronze alloy revealed weak anti-microbe activity to S. aureus and no effect to kill other pathogens. Coins made of stainless steel also can’t resist bacteria growth. 3) Surprisingly, one cent coins of USA which were made of 97.5% Zinc and 2.5% Cu showed a significant antimicrobial capability, the average inhibition zone of these five pathogens is 45.5 mm.

Keywords: antibiotic sensitivity, bacteria, currency, coins, parasites

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1548 Utilizing the RhlR/RhlI Quorum Sensing System to Express the ß-Galactosidase Reporter Gene by Using the N-Butanoyl Homoserine Lactone and N-Hexanoyl Homoserine Lactone

Authors: Ngoc Tu Truong, Nuong T. Bui, Ben Rao, Ya L. Shen

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Quorum sensing is a phenomenon present in many gram-negative bacteria that allows bacterial communication and controlled expression of a large suite of genes through quorum sensing signals - N-acyl homoserine lactones (AHLs). In order to investigate the ability of the rhlR/rhlI quorum sensing system in Pseudomonas aeruginosa to express the ß-Galactosidase reporter gene, an engineered E. coli strain EpHL02, was genetically engineered. This engineered E. coli strain EpHL02 responded to the presence of the N-butanoyl homoserine lactone and N-hexanoyl homoserine lactone to express the ß-Galactosidase reporter gene at a concentration limit of 5x10⁻⁸ M. This was also found to be comparable to AHLs extraction from Serratia marcescens H31. Moreover, we examined this ability of this engineered E. coli strain for respond of AHLs from extractions of Pseudomonas aeruginosa ATCC9027. The results demonstrated that the rhlR/rhlI quorum sensing system can express the ß-Galactosidase reporter gene by using the N-butanoyl homoserine lactone, N-hexanoyl homoserine lactone and AHLs from extractions of Serratia marcescens H31 and Pseudomonas aeruginosa ATCC9027 in the engineered E. coli strain EpHL02.

Keywords: N-butanoyl homoserine lactone, C4-HSL, N-hexanoyl homoserine lactone, C6-HSL, Pseudomonas aeruginosa, quorum sensing, Serratia marcescens, ß-galactosidase reporter gene

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1547 Quantifying the Protein-Protein Interaction between the Ion-Channel-Forming Colicin A and the Tol Proteins by Potassium Efflux in E. coli Cells

Authors: Fadilah Aleanizy

Abstract:

Colicins are a family of bacterial toxins that kill Escherichia coli and other closely related species. The mode of action of colicins involves binding to an outer membrane receptor and translocation across the cell envelope, leading to cytotoxicity through specific targets. The mechanism of colicin cytotoxicity includes a non-specific endonuclease activity or depolarization of the cytoplasmic membrane by pore-forming activity. For Group A colicins, translocation requires an interaction between the N-terminal domain of the colicin and a series of membrane- bound and periplasmic proteins known as the Tol system (TolB, TolR, TolA, TolQ, and Pal and the active domain must be translocated through the outer membranes. Protein-protein interactions are intrinsic to virtually every cellular process. The transient protein-protein interactions of the colicin include the interaction with much more complicated assemblies during colicin translocation across the cellular membrane to its target. The potassium release assay detects variation in the K+ content of bacterial cells (K+in). This assays is used to measure the effect of pore-forming colicins such as ColA on an indicator organism by measuring the changes of the K+ concentration in the external medium (K+out ) that are caused by cell killing with a K+ selective electrode. One of the goals of this work is to employ a quantifiable in-vivo method to spot which Tol protein are more implicated in the interaction with colicin A as it is translocated to its target.

Keywords: K+ efflux, Colicin A, Tol-proteins, E. coli

Procedia PDF Downloads 376
1546 CoFe₂O₄ as Anode for Enhanced Energy Recovery in Microbial Fuel Cell

Authors: Mehak Munjal, Raj Kishore Sharma, Gurmeet Singh

Abstract:

Microbial Fuel Cells (MFCs) are an alternative sustainable approach that utilize bacteria present in waste water as a bio-catalyst for the production of energy. It is a promising growing technology with minimal requirement for chemical supplements. Here electrode material plays a vital role in its performance. The present study represents CoFe2O4 spinel as a novel anode material in the MFC. It not only improve the bacterial metabolics but also enhance the power output. Generally, biocompatible conductive carbon paper/cloth, graphite and stainless steel are utilised as anode in MFCs. However, these materials lack electrochemical activity for anodic microbial reaction. Therefore, we developed CoFe2O4 on graphite sheet which enhanced the anodic charge transfer process. Redox pair in CoFe2O4 helped in improvement of extracellular electron transfer, thereby enhancing the performance. The physical characterizations (FT-IR, XRD, Raman) and electrochemical measurements demonstrate the strong interaction with E.coli bacteria and thus providing an excellent power density i.e. 1850 mW/m2 .The maximum anode half -cell potential is measured to be 0.65V. Therefore, use of noble metal free anodic material further decrease the cost and the long term cell stability makes it an effective material for practical applications.

Keywords: microbial fuel cell, cobalt ferrite, E. coli, bioelectricity

Procedia PDF Downloads 110
1545 Bacterial Contamination of Kitchen Sponges and Cutting Surfaces and Disinfection Procedures

Authors: Hayyan I Al Taweil

Abstract:

Background: The most common of bacterium in kitchen sponges and cutting surfaces which can play a task within the cross-contamination of foods, fomites and hands by foodborne pathogens. Aims and Objectives: This study investigated the incidence of bacterium in kitchen Sponge, and cutting surfaces. Material and methods: a complete of twenty four kitchen Sponges were collected from home kitchens and therefore the numbers of mesotrophic microorganism, coliform microorganism, E. coli, Salmonella, genus {pseudomonas|bacteria genus} and staphylococci in every kitchen Sponges were determined. Microbiological tests of all sponges for total mesophilic aerobic microorganism, S. aureus, Pseudomonas, Salmonella spp., and E. coli were performed on days 3, 7, and 14 by sampling. The sponges involved in daily use in kitchens countenosely with the dishwasher detergent a minimum of doubly daily Results: Results from the overall mesophilic aerobic microorganism, indicate a major increase within the variety of log CFU/ml. the amount of E. coli was reduced, Salmonella spp. was stabled, S. aureus was enhanced from the sponges throughout fourteen days. Genus Pseudomonas was enhanced and was the dominant micro flora within the sponges throughout fourteen days.

Keywords: Kitchen Sponges, Microbiological Contamination, Disinfection; cutting surface; , Cross-Contamination

Procedia PDF Downloads 110
1544 The Effect of Extracts of 12 Local Medicinal Plants Against Uropathogenic Escherichia Coli

Authors: Hafida Merzouk

Abstract:

Urinary tract infections are among the most serious public health issues in all age groups. Thus, the empirical therapy should based on local levels of resistance, as indicated in several studies from different countries, to effectively avoid the emergence of multidrug-resistant bacterial strains and recurrent infections. Numerous effective antibiotic treatments are available, but wouldbe ineffective for treating recurrent cystitis caused by a urinary tract infection, as well as the emergence of drug resistance. That iswhy the aim of this study was to highlight the antibacterial and the antioxidant activity of 11 medicinal plants used traditionally in Algeria against E. coli, the most responsible urinary tract infections. First, the extraction of total polyphenols with aqueous acetone showed variable yields. The highest yield was obtained by Asplenium trichomanes with 27%, followed by Petroselinum crispum and Ciannamomum cassia with an equal yield of 21%. Artemisia herba-alba gave the lowest yield (9%). The extracts of different plants showed variable contents of phenolic compounds. Reducing power and DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity revealed that most of the extracts studied had significant activity. The anti-free radical activity was very high in the extract of A splenium adiantum-nigrum compared with the other extracts studied, but Petroselinum crispum and Parietaria officinalis had the lowest reducing activity; Antibacterial activity was determined on E. coli strainsusing the diffusion, MICs (Minimum Inhibitory Concentrations) and MBCs (Minimum Bactericidal concentrations) methods. The strains tested were sensitive to most extracts studied, except Asplenium adiantum-nigrum extract, for which both strains showed resistance.

Keywords: E. coli, medicinal plants, phenolic compounds, urinary infections

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1543 Risk Factors for High Resistance of Ciprofloxacin Against Escherichia coli in Complicated Urinary Tract Infection

Authors: Liaqat Ali, Khalid Farooq, Shafieullah Khan, Nasir Orakzai, Qudratullah

Abstract:

Objectives: To determine the risk factors for high resistance of ciprofloxacin in complicated urinary tract infections. Materials and Methods: It is an analytical study that was conducted in the department of Urology (Team ‘C’) at Institute of Kidney Diseases Hayatabad Peshawar from 1st June 2012 till 31st December 2012. Total numbers of 100 patients with complicated UTI was selected in the study. Multivariate analysis and linear regression were performed for the detection of risk factors. All the data was recorded on structured Proforma and was analyzed on SPSS version 17. Results: The mean age of the patient was 55.6 years (Range 3-82 years). 62 patients were male while 38 patients were female. 66 isolates of E-Coli were found sensitive to ciprofloxacin while 34 isolates were found Resistant for ciprofloxacin. Using multivariate analysis and linear regression, an increasing age above 50 (p=0.002) History of urinary catheterization especially for bladder outflow obstruction (p=0.001) and previous multiple use of ciprofloxacin (p=0.001) and poor brand of ciprofloxacin were found to be independent risk factors for high resistance of ciprofloxacin. Conclusion: UTI is common illness across the globe with increasing trend of antimicrobial resistance for ciprofloxacin against E Coli in complicated UTI. The risk factors for emerging resistance are increasing age, urinary catheterization and multiple use and poor brand of ciprofloxacin.

Keywords: urinary tract infection, ciprofloxacin, urethral catheterization, antimicrobial resistance

Procedia PDF Downloads 301
1542 Supplementation of Citrulline with Lactic Acid Bacteria Protects Foodborne Pathogens Adhesion and Improves the Cell Integrity on the Intestinal Epithelial Cell

Authors: Sze Wing Ho, Nagendra P. Shah

Abstract:

Lactic acid bacteria (LAB) have shown the beneficial effects on human gastrointestinal tract, such as protects diarrhea induced by lactose intolerance or enteric pathogens. Citrulline is a non-protein amino acid and also the precursors of arginine and nitric oxide, it has shown to enhance intestinal barrier function. Citrulline has shown to improve the growth of some strains of LAB, it is important for LAB to have a sufficient cell concentration to contribute the effects. Therefore, the aims of this study were to investigate the effect of combining citrulline with LAB on the anti-adhesion effect against pathogens and the effect on the cell integrity. The effect of citrulline on selected LAB was determined by incubating in 0%, 0.1% or 0.2% citrulline enriched MRS broth for 18 h. The adhesion ability of LAB and the anti-adhesion effect of LAB and citrulline against pathogens were performed on IPEC-J2 cell line. Transepithelial electrical resistance (TEER) assay was used to measure the tight junction (TJ) integrity. TJ proteins (claudin-1, occludin and zonula occluden-1 (ZO-1)) were determined by western blot analysis. It found that the growth of Lactobacillus helveticus ASCC 511 was significantly stimulated by 0.2% citrulline compared with control during 18 h fermentation. The adhesion of L. helveticus ASCC 511 and Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) ASCC 756 was increased when supplemented with citrulline. Citrulline has shown significant inhibitory effect on the adhesion of Escherichia coli PELI0480 (O157:H7), Shigella sonnei ATCC 25931, Staphyloccocus aureus CMCC26003 and Cronobacter sakazakii ATCC 29544. The anti-adhesion effect of L. helveticus ASCC 511, L. bulgaricus ASCC 756 and Lactobacillus paracasei ASCC 276 against Cronobacter sakazakii ATCC 29544 was significantly enhanced with citrulline supplementation. Treatments with citrulline and LAB were able to maintain the TEER of IPEC-J2 cell and shown the positive effect on the TJ proteins. In conclusion, citrulline had stimulating effect on some strains of LAB and determined to improve the adhesion of LAB on intestinal epithelial cell, to enhance the inhibitory effect on enteric pathogens adhesion as well as had beneficial effects on maintaining cell integrity. It implied LAB supplemented with citrulline might have advantageous effects on gastrointestinal tracts.

Keywords: citrulline, lactic acid bacteria, amino acid, anti-adhesion effect, cell integrity

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1541 Defense Priming from Egg to Larvae in Litopenaeus vannamei with Non-Pathogenic and Pathogenic Bacteria Strains

Authors: Angelica Alvarez-Lee, Sergio Martinez-Diaz, Jose Luis Garcia-Corona, Humberto Lanz-Mendoza

Abstract:

World aquaculture is always looking for improvements to achieve productions with high yields avoiding the infection by pathogenic agents. The best way to achieve this is to know the biological model to create alternative treatments that could be applied in the hatcheries, which results in greater economic gains and improvements in human public health. In the last decade, immunomodulation in shrimp culture with probiotics, organic acids and different carbon sources has gained great interest, mainly in larval and juvenile stages. Immune priming is associated with a strong protective effect against a later pathogen challenge. This work provides another perspective about immunostimulation from spawning until hatching. The stimulation happens during development embryos and generates resistance to infection by pathogenic bacteria. Massive spawnings of white shrimp L. vannamei were obtained and placed in experimental units with 700 mL of sterile seawater at 30 °C, salinity of 28 ppm and continuous aeration at a density of 8 embryos.mL⁻¹. The immunostimulating effect of three death strains of non-pathogenic bacterial (Escherichia coli, Staphylococcus aureus and Bacillus subtilis) and a pathogenic strain for white shrimp (Vibrio parahaemolyticus) was evaluated. The strains killed by heat were adjusted to O.D. 0.5, at A 600 nm, and directly added to the seawater of each unit at a ratio of 1/100 (v/v). A control group of embryos without inoculum of dead bacteria was kept under the same physicochemical conditions as the rest of the treatments throughout the experiment and used as reference. The duration of the stimulus was 12 hours, then, the larvae that hatched were collected, counted and transferred to a new experimental unit (same physicochemical conditions but at a salinity of 28 ppm) to carry out a challenge of infection against the pathogen V. parahaemolyticus, adding directly to seawater an amount 1/100 (v/v) of the live strain adjusted to an OD 0.5; at A 600 nm. Subsequently, 24 hrs after infection, nauplii survival was evaluated. The results of this work shows that, after 24 hrs, the hatching rates of immunostimulated shrimp embryos with the dead strains of B. subtillis and V. parahaemolyticus are significantly higher compared to the rest of the treatments and the control. Furthermore, survival of L. vanammei after a challenge of infection of 24 hrs against the live strain of V. parahaemolyticus is greater (P < 0.05) in the larvae immunostimulated during the embryonic development with the dead strains B. subtillis and V. parahaemolyticus, followed by those that were treated with E. coli. In summary superficial antigens can stimulate the development cells to promote hatching and can have normal development in agreeing with the optical observations, plus exist a differential response effect between each treatment post-infection. This research provides evidence of the immunostimulant effect of death pathogenic and non-pathogenic bacterial strains in the rate of hatching and oversight of shrimp L. vannamei during embryonic and larval development. This research continues evaluating the effect of these death strains on the expression of genes related to the defense priming in larvae of L. vannamei that come from massive spawning in hatcheries before and after the infection challenge against V. parahaemolyticus.

Keywords: immunostimulation, L. vannamei, hatching, survival

Procedia PDF Downloads 115
1540 In Vitro Assessment of Anti-microbial Properties of Murraya Koenigii Extract

Authors: Kinza Khan, Dad Muhmmad, Asif Saleem, Nadia Mukhtar, Tahir Yaqub

Abstract:

Ethomedicines are more commonly used in underdeveloped and developing countries. These medicines are sometimes more potent in controlling microbial infections than conventional medicines. Medicinal plants have been common practice to cure many diseases for centuries. Murraya koenigii is one of these plants and is commonly used in South Asian countries as a flavoring agent in food. To evaluate its anti-microbial activity, six different bacterial strains (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, Bacillus cereus and Klebsiella pneumonia were used. N-hexane extract of Murraya koenigii leaves shows maximum activity against Bacillus cereus. Acetone extract of Murraya koenigii shoots showed more efficient activity against Pseudomonas aeruginosa Dichloromethane extracts showed maximum activity against Bacillus cereus. Ethanol extract exhibited maximum activity against Pseudomonas aeruginosa and Klebsiella pneumoniae. The methanol extract of Murraya koenigii shoots displayed maximum antibacterial activity against Bacillus cereus. Antifungal activity Ethanol extract was more effective against Candida albicans.

Keywords: ethnomedicines, bacteria, fungi, murraya koenigii, antimicrobial activity

Procedia PDF Downloads 62
1539 Modification of Escherichia coli PtolT Expression Vector via Site-Directed Mutagenesis

Authors: Yakup Ulusu, Numan Eczacıoğlu, İsa Gökçe, Helen Waller, Jeremy H. Lakey

Abstract:

Besides having the appropriate amino acid sequence to perform the function of proteins, it is important to have correct conformation after this sequence to process. To consist of this conformation depends on the amino acid sequence at the primary structure, hydrophobic interaction, chaperones and enzymes in charge of folding etc. Misfolded proteins are not functional and tend to be aggregated. Cysteine originating disulfide cross-links make stable this conformation of functional proteins. When two of the cysteine amino acids come side by side, disulfide bond is established that forms a cystine bridge. Due to this feature cysteine plays an important role on the formation of three-dimensional structure of many proteins. There are two cysteine amino acids (C44, C69) in the Tol-A-III protein. Unlike protein disulfide bonds from within his own, any non-specific cystine bridge causes a change in the three dimensional structure of the protein. Proteins can be expressed in various host cells as directly or fusion (chimeric). As a result of overproduction of the recombinant proteins, aggregation of insoluble proteins in the host cell can occur by forming a crystal structure called inclusion body. In general fusion proteins are produced for provide affinity tags to make proteins more soluble and production of some toxic proteins via fusion protein expression system like pTolT. Proteins can be modified by using a site-directed mutagenesis. By this way, creation of non-specific disulfide crosslinks can be prevented at fusion protein expression system via the present cysteine replaced by another amino acid such as serine, glycine or etc. To do this, we need; a DNA molecule that contains the gene that encodes for the target protein, required primers for mutation to be designed according to site directed mutagenesis reaction. This study was aimed to be replaced cysteine encoding codon TGT with serine encoding codon AGT. For this sense and reverse primers designed (given below) and used site-directed mutagenesis reaction. Several new copy of the template plasmid DNA has been formed with above mentioned mutagenic primers via polymerase chain reaction (PCR). PCR product consists of both the master template DNA (wild type) and the new DNA sequences containing mutations. Dpn-l endonuclease restriction enzyme which is specific for methylated DNA and cuts them to the elimination of the master template DNA. E. coli cells obtained after transformation were incubated LB medium with antibiotic. After purification of plasmid DNA from E. coli, the presence of the mutation was determined by DNA sequence analysis. Developed this new plasmid is called PtolT-δ.

Keywords: site directed mutagenesis, Escherichia coli, pTolT, protein expression

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1538 The Application of Whole-Cell Luminescent Biosensors for Assessing Bactericidal Properties of Medicinal Plants

Authors: Yuliya Y. Gavrichenko

Abstract:

Background and Aims: The increasing bacterial resistance to almost all the available antibiotics has encouraged scientists to search for alternative sources of antibacterial agents. Nowadays, it is known that many plant secondary metabolites have diverse biological activity. These compounds can be potentially active against human bacterial and viral infections. Extended research has been carried out to explore the use of the luminescent bacterial test as a rapid, accurate and inexpensive method to assess the antibacterial properties and to predict the biological activity spectra for plant origin substances. Method: Botanical material of fifteen species was collected from their natural and cultural habitats on the Crimean peninsula. The aqueous extracts of following plants were tested: Robinia pseudoacacia L., Sideritis comosa, Cotinus coggygria Scop., Thymus serpyllum L., Juglans regia L., Securigera varia L., Achillea millefolium L., Phlomis taurica, Corylus avellana L., Sambucus nigra L., Helichrysum arenarium L., Glycyrrhiza glabra L., Elytrigia repens L., Echium vulgare L., Conium maculatum L. The test was carried out using luminous strains of marine bacteria Photobacterium leiognathi, which was isolated from the Sea of Azov as well as four Escherichia coli MG1655 recombinant strains harbouring Vibrio fischeri luxCDABE genes. Results: The bactericidal capacity of plant extracts showed significant differences in the study. Cotinus coggygria, Phlomis taurica, Juglans regia L. proved to be the most toxic to P. leiognathi. (EC50 = 0.33 g dried plant/l). Glycyrrhiza glabra L., Robinia pseudoacacia L., Sideritis comosa and Helichrysum arenarium L. had moderate inhibitory effects (EC50 = 3.3 g dried plant/l). The rest of the aqueous extracts have decreased the luminescence of no more than 50% at the lowest concentration (16.5 g dried plant/l). Antibacterial activity of herbal extracts against constitutively luminescent E. coli MG1655 (pXen7-lux) strain was observed at approximately the same level as for P. leiognathi. Cotinus coggygria and Conium maculatum L. extracts have increased light emission in the mutant E. coli MG1655 (pFabA-lux) strain which is associated with cell membranes damage. Sideritis comosa, Phlomis taurica, Juglans regia induced SOS response in E. coli (pColD-lux) strain. Glycyrrhiza glabra L. induced protein damage response in E. coli MG1655 (pIbpA-lux) strain. Conclusion: The received results have shown that the plants’ extracts had nonspecific antimicrobial effects against both E. coli (pXen7-lux) and P. leiognathi biosensors. Mutagenic, cytotoxic and protein damage effects have been observed. In general, the bioluminescent inhibition test result correlated with the traditional use of screened plants. It leads to the following conclusion that whole-cell luminescent biosensors could be the indicator of overall plants antibacterial capacity. The results of the investigation have shown a possibility of bioluminescent method in medicine and pharmacy as an approach to research the antibacterial properties of medicinal plants.

Keywords: antibacterial property, bioluminescence, medicinal plants, whole-cell biosensors

Procedia PDF Downloads 95
1537 Application of Box-Behnken Response Surface Design for Optimization of Essential Oil Based Disinfectant on Mixed Species Biofilm

Authors: Anita Vidacs, Robert Rajko, Csaba Vagvolgyi, Judit Krisch

Abstract:

With the optimization of a new disinfectant the number of tests could be decreased and the cost of processing too. Good sanitizers are eco-friendly and allow no resistance evolvement of bacteria. The essential oils (EOs) are natural antimicrobials, and most of them have the Generally Recognized As Safe (GRAS) status. In our study, the effect of the EOs cinnamon, marjoram, and thyme was investigated against mixed species bacterial biofilms of Escherichia coli, Listeria monocytogenes, Pseudomonas putida, and Staphylococcus aureus. The optimal concentration of EOs, disinfection time and level of pH were evaluated with the aid of Response Surface Box-Behnken Design (RSD) on 1 day and 7 days old biofilms on metal, plastic, and wood surfaces. The variable factors were in the range of 1-3 times of minimum bactericide concentration (MBC); 10-110 minutes acting time and 4.5- 7.5 pH. The optimized EO disinfectant was compared to industrial used chemicals (HC-DPE, Hypo). The natural based disinfectants were applicable; the acting time was below 30 minutes. EOs were able to eliminate the biofilm from the used surfaces except from wood. The disinfection effect of the EO based natural solutions was in most cases equivalent or better compared to chemical sanitizers used in food industry.

Keywords: biofilm, Box-Behnken design, disinfectant, essential oil

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1536 Synthesis of Brominated Pyrazoline Derived from Chalcone and Its Antimicrobial Activity

Authors: Annisa I. Reza, Jasril Karim

Abstract:

Despite the availability of antimicrobial agents in the market, the urge to study and find other chemical compounds with the better potential of replacing them still tempting the scientists. This experiment is in the aim to explore a novel brominated pyrazoline ring which was made from intermediate chalcone as a candidate to answer the challenge. Using green chemistry approach by microwave irradiation from domestic oven, both known chalcone and 5-(2-bromophenyl)-3-(naphthalen-1-yl)-4,5-dihydro-1H-pyrazole were successfully synthesized. Pyrazoline’s structure was confirmed based on UV, IR, ¹H-NMR, ¹³C-NMR and MS and together with its intermediate were examined against some microorganisms (Bacillus subtilis, Escherichia coli, and Candida albicans) under agar diffusion method. The results collected during experiment revealed that both tested compounds showed weak activity on B.subtilis which was proven by a zone of inhibitions, while there was no zone of inhibitions observed in E. coli and C. albicans. This is suggested because of the bulky structure around pyrazoline could not provide the main ring to interact with microbial’s cell wall. The study shows that the proposed compound had the low capability as a promising antimicrobial agent, yet it still enriches the information about pyrazoline ring.

Keywords: antimicrobial, chalcone, microwave irradiation, pyrazoline

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1535 Parallel among Urinary Tract Infection in Diabetic and Non-Diabetic Patients: A Case Study

Authors: Khaled Khleifat

Abstract:

This study detects the bacterial species that responsible for UTI in both diabetic patients and non-diabetic patients, Jordan. 116 urine samples were investigated in order to determine UTI-causing bacteria. These samples distributed unequally between diabetic male (12) and diabetic female (25) and also non-diabetic male (13) and non-diabetic female (66). The results represent that E.coli is responsible for UTI in both diabetic and non-diabetic patients (15.5% and 29.3% respectively) with large proportion (44.8%). This study showed that not all bacterial species that isolated from the non-diabetic sample could be isolated from diabetic samples. E. coli (15.5%), P. aeruginosa (4.3%), K. pneumonia (1.7%), P. mirabilis (2.6%), S. marcescens (0.9%), S. aureus (1.7%), S. pyogenes (1.7%), E. faecalis (0.9%), S. epidermidis (1.7%) and S. saprophyticus (0.9%). But E. aerogenes, E. cloacae, C. freundii, A. baumannii and B. subtilis are five bacterial species that can’t isolate from all diabetic samples. This study shows that for the treatment of UTI in both diabetic and non-diabetic patients, Chloramphenicol (30 μg), Ciprofloxacin (5 μg) and Vancomycin (30 μg) are more favorable than other antibiotics. In the same time, Cephalothin (30μg) is not recommended.

Keywords: urinary tract infections, diabetes mellitus, bacterial species, infections

Procedia PDF Downloads 299
1534 Impedance Based Biosensor for Agricultural Pathogen Detection

Authors: Rhea Patel, Madhuri Vinchurkar, Rajul Patkar, Gopal Pranjale, Maryam Shojaei Baghini

Abstract:

One of the major limitations on food resources worldwide is the deterioration of plant products due to pathogenic infections. Early screening of plants for pathogenic infections can serve as a boon in the Agricultural sector. The standard microbiology techniques has not kept pace with the rapid enumeration and automated methods for bacteria detection. Electrochemical Impedance Spectroscopy (EIS) serves as a label free bio sensing technique to monitor pathogens in real time. The changes in the electrical impedance of a growing bacterial culture can be monitored to detect activity of microorganisms. In this study, we demonstrate development of a gold interdigitated electrode (gold IDE) based impedance biosensor to detect bacterial cells in real on-field crop samples. To calibrate our impedance measurement system, nutrient broth suspended Escherichia coli cells were used. We extended this calibrated protocol to identify the agricultural pathogens in real potato tuber samples. Distinct difference was seen in the impedance recorded for the healthy and infected potato samples. Our results support the potential application of this Impedance based biosensor in Agricultural pathogen detection.

Keywords: agriculture, biosensor, electrochemical impedance spectroscopy, microelectrode, pathogen detection

Procedia PDF Downloads 118
1533 Effects of Bacteria on Levels of AFM1 in Phosphate Buffer at Different Level of Energy Source

Authors: Ali M. Elgerbi, Obied A. Alwan, Al-Taher O. Alzwei, Abdurrahim A. Elouzi

Abstract:

The binding of AFM1 to bacteria in phosphate buffer solution depended on many factors such as: availability of energy, incubation period, species and strain of bacteria. Increase in concentration of sugar showed higher removal of AFM1 and faster than in phosphate buffer alone. With 1.0% glucose lactic acid bacteria and bifidobacteria showed toxin removal ranging from 7.7 to 39.7% whereas with 10.0% glucose the percentage removal was 21.8 to 45.4% at 96 hours of incubation.

Keywords: aflatoxin M1, lactic acid bacteria, bifidobacteria , binding, phosphate buffer

Procedia PDF Downloads 475