Search results for: bacterial contamination

Authors: Shashank Gahlaut, Chandrashekhar Sharan, J. P. Singh

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Increasing incidence of antibiotic-resistant bacteria is a big concern for the treatment of pathogenic diseases. The effect of treatment of patients with antibiotics often leads to the evolution of antibiotic resistance in the pathogens. The detection of antibiotic or antimicrobial resistant bacteria (microbes) is quite essential as it is becoming one of the big threats globally. Here we propose a novel technique to tackle this problem. We are taking a step forward to prevent the infections and diseases due to drug resistant microbes. This detection is based on some unique features of silver (a noble metal) nanorods (AgNRs) which are fabricated by a physical deposition method called thermal glancing angle deposition (GLAD). Silver nanorods are found to be highly sensitive and selective for hydrogen sulfide (H2S) gas. Color and water wetting (contact angle) of AgNRs are two parameters what are effected in the presence of this gas. H₂S is one of the major gaseous products evolved in the bacterial metabolic process. It is also known as gasotransmitter that transmits some biological singles in living systems. Nitric Oxide (NO) and Carbon mono oxide (CO) are two another members of this family. Orlowski (1895) observed the emission of H₂S by the bacteria for the first time. Most of the microorganism produce these gases. Here we are focusing on H₂S gas evolution to determine live/dead and antibiotic-resistant bacteria. AgNRs array has been used for the detection of H₂S from micro-organisms. A mobile app is also developed to make it easy, portable, user-friendly, and cost-effective.

Keywords: antibiotic resistance, hydrogen sulfide, live and dead bacteria, mobile app

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Authors: Nourmalita Safitri Ningsih, Ridwan, Iqri Puspa Yunanda

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The aim of this study was to utilize the waste from slaughterhouses for chicken feed ingredients is probiotic. Livestock waste produced by livestock activities such as feces, urine, food remains, as well as water from livestock and cage cleaning. The process starts with the isolation of bacteria. Rumen fluid is taken at Slaughterhouse Giwangan, Yogyakarta. Isolation of Lactobacillus ruminus is done by using de Mann Rogosa Sharpe (MRS) medium. In the sample showed a rod-shaped bacteria are streaked onto an agar plates. After it was incubated at 37ºC for 48 hours, after which it is observed. The observation of these lactic acid bacteria it will show a clear zone at about the colony. These bacterial colonies are white, round, small, shiny on the agar plate mikroenkapsul In the manufacturing process carried out by the method of freeze dried using skim milk in addition capsulated material. Then the results of these capsulated bacteria are mixed with feed for livestock. The results from the mixing of capsulated bacteria in feed are to increase the quality of animal feed so as to provide a good effect on livestock. Scanning electron microscope testing we have done show the results of bacteria have been shrouded in skim milk. It can protect the bacteria so it is more durable in use. The observation of the bacteria showed a sheath on Lactobacillus sp. Preservation of bacteria in this way makes the bacteria more durable for use. As well as skim milk can protect bacteria that are resistant to the outside environment. Results of probiotics in chicken feed showed significant weight gain in chickens. Calculation Anova (P <0.005) shows the average chicken given probiotics her weight increased.

Keywords: chicken, probiotics, waste, Lactobacillus sp, bacteria

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Authors: Ogbuagu Josephat Okechukwu, Okeke Abuchi Princewill, Arinze Rosemary Uche, Tabugbo Ifeyinwa Blessing, Ogbuagu Adaora Stellamaris

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Phthalates or Phthalate esters (PAEs), categorized as an endocrine disruptor and persistent organic pollutants, are known for their environmental contamination and toxicological effects. In this study, the concentration of selected phthalates was determined across the sampling site to investigate their occurrence and the ecological and health risk assessment they pose to the environment. Water and sediment samples were collected following standard procedures. Solid phase and ultrasonic methods were used to extract seven different PAEs, which were analyzed by Gas Chromatography with Mass Detector (GCMS). The analytical average recovery was found to be within the range of 83.4% ± 2.3%. The results showed that PAEs were detected in six out of seven samples with a high percentage of detection rate in water. Di-n-butyl phthalate (DPB) and disobutyl phthalates (DiBP) showed a greater detection rate compared to other PAE monomers. The concentration of PEs was found to be higher in sediment samples compared to water samples due to the fact that sediments serve as a sink for most persistent organic pollutants. The concentrations of PAEs in water samples and sediments ranged from 0.00 to 0.23 mg/kg and 0.00 to 0.028 mg/l, respectively. Ecological risk assessment using the risk quotient method (RQ) reveals that the estimated environmental risk caused by phthalates lies within the moderate level as RQ ranges from 0.1 to 1.0, whereas the health risk assessment caused by phthalates on estimating the average daily dose reveals that the ingestion of phthalates was found to be approaching permissible limit which can cause serious carcinogenic occurrence in the human system with time due to excess accumulation.

Keywords: phthalates, endocrine disruptor, risk assessment, ecological risk, health risk

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Authors: Wajid Rehman, Sirajul Haq, Bakhtiar Muhammad, Syed Fahad Hassan, Amin Badshah, Muhammad Waseem, Fazal Rahim, Obaid-Ur-Rahman Abid, Farzana Latif Ansari, Umer Rashid

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Five novel triorganotin (IV) compounds have been synthesized and characterized. The tin atom is penta-coordinated to assume trigonal-bipyramidal geometry. Using in silico derived parameters; the objective of our study is to design and synthesize promiscuous antibacterials potent enough to combat resistance. Among various synthesized organotin (IV) complexes, compound 5 was found as potent antibacterial agent against various bacterial strains. Further lead optimization of drug-like properties was evaluated through in silico predictions. Data mining and computational analysis were utilized to derive compound promiscuity phenomenon to avoid drug attrition rate in designing antibacterials. Xanthine oxidase and human glucose- 6-phosphatase were found as only true positive off-target hits by ChEMBL database and others utilizing similarity ensemble approach. Propensity towards a-3 receptor, human macrophage migration factor and thiazolidinedione were found as false positive off targets with E-value 1/4> 10^-4 for compound 1, 3, and 4. Further, displaying positive drug-drug interaction of compound 1 as uricosuric was validated by all databases and docked protein targets with sequence similarity and compositional matrix alignment via BLAST software. Promiscuity of the compound 5 was further confirmed by in silico binding to different antibacterial targets.

Keywords: antibacterial activity, drug promiscuity, ADMET prediction, metallo-pharmaceutical, antimicrobial resistance

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Authors: H. Nabahat, E. Amiri, F. AzaditalabDavoudabadi, N. Zaeri

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Tooth decay is one of the most common forms of oral and dental illness in the world, which causes huge costs of treatment, especially in high-risk groups such as people with oral dry mouth, prevention and control of it are very important. The use of traditional treatments such as extraction of drugs from medicinal plants is of paramount importance to Iran and the international community as well. The present study was conducted with the aim of investigating the antibacterial effect of the extract of Salvia officinalis and Mentha pulegium, which are the most commonly used drugs in the treatment of oral and teeth bacterial (Streptococcus mutant, Lactobacillus rhamnosis, and Actinomyces viscosis) in vitro method. In this experimental study, two herbs of Salvia and Mentha were prepared by maceration of hydroalcoholic extract, and the antibacterial effect was evaluated by broth macro dilution on streptococcal mutagen bacteria, lactobacillus rhamnosis, and viscose actinomycosis. The results were analyzed by the Whitney Mann test (P > 0.05). The results showed that the minimum inhibitory concentration (MIC) of the salmonella extract for Streptococcus mutan were 6.25 and 12.5 μg/ml, respectively, for lactobacillus of 1.56 and 3.12 μg/ml, respectively, and for actinomycosis viscose, The order of 12.5 and 100 μg/ml was obtained. As a result, broth macro dilution showed that both extracts of Salvia and Mentha had an inhibitory effect on all three species of bacteria. This effect for Salvia was significantly (P < 0.05) more than Mentha and was within the concentration range of both the extracts and had a bactericidal effect on all three bacteria.

Keywords: antibacterial effect, dental bacteria, herbal extracts , salvia officinalis, mentha pulegium

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Authors: M. Gerasimou, S. Mantzoukis, P. Christodoulou, N. Varsamis, G. Kolliopoulou, N. Zotos

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Purpose: Microbial infection of the blood is a serious condition where bacteria invade the bloodstream and cause systemic disease. In such cases, blood cultures are performed. Blood cultures are a key diagnostic test for intensive care unit (ICU) patients. Material and method: The BacT/Alert system, which measures the production of carbon dioxide with metabolic organisms, is used. The positive result in the BacT/Alert system is followed by culture in the following selective media: Blood, Mac Conkey No 2, Chocolate, Mueller Hinton, Chapman and Sabaureaud agar. Gram staining method was used to differentiate bacterial species. The microorganisms were identified by biochemical techniques in the automated Microscan (Siemens) system and followed by a sensitivity test on the same system using the minimum inhibitory concentration MIC technique. The sensitivity test is verified by a Kirby Bauer-based test. Results: In 2017 the Laboratory of Microbiology received 3347 blood cultures. Of these, 170 came from the ICU. 116 found positive. Of these S. epidermidis was identified in 42, A. baumannii in 27, K. pneumoniae in 12 (4 of these KPC ‘Klebsiella pneumoniae carbapenemase’), S. hominis in 8, E. faecium in 7, E. faecalis in 5, P. aeruginosa in 3, C. albicans in 3, S. capitis in 2, K. oxytoca in 2, P. mirabilis in 2, E. coli in 1, S. intermidius in 1 and S. lugdunensis in 1. Conclusions: The study of epidemiological data and microbial resistance phenotypes is essential for the choice of therapeutic regimen for the early treatment and limitation of multivalent strains, while it is a crucial factor to solve diagnostic problems.

Keywords: blood culture, bloodstream, infection, intensive care unit

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Authors: Sharda Nara, Bansi Dhar Malhotra

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Investigation of the vitamins as an electron transfer mediator could significantly assist in merging the area of tissue engineering and electronics required for the implantable therapeutic devices. The present study report that the molecules of folic acid released by Providencia rettgeri via fermentation route under the anoxic condition of the microbial fuel cell (MFC) exhibit characteristic electrochemical and optical properties, as indicated by absorption spectroscopy, photoluminescence (PL), and cyclic voltammetry studies. The absorption spectroscopy has depicted an absorption peak at 263 nm with a small bulge around 293 nm on day two of bacterial culture, whereas an additional peak was observed at 365 nm on the twentieth day. Furthermore, the PL spectra has indicated that the maximum emission occurred at various wavelengths 420, 425, 440, and 445 nm when excited by 310, 325, 350, and 365 nm. The change of emission spectra with varying excitation wavelength might be indicating the presence of tunable optical bands in the folic acid molecules co-related with the redox activity of the molecules. The results of cyclic voltammetry studies revealed that the oxidation and reduction occurred at 0.25V and 0.12V, respectively, indicating the electrochemical behavior of the folic acid. This could be inferred that the released folic acid molecules in a MFC might undergo inter as well as intra molecular electron transfer forming different intermediate states while transferring electrons to the electrode surface. Synchronization of electrochemical and optical properties of folic acid molecules could be potentially promising for the designing of electroactive scaffold and biocompatible conductive surface for the applications of tissue engineering and biofuel cells, respectively.

Keywords: biofuel cell, electroactivity, folic acid, tissue engineering

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Authors: Ana Luiza Da Gama E Souza

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This article aims to discuss the problem of food insecurity in Brazil in what it refers to contamination of food by chemical substances such as herbicides, pesticides, and other contaminants. The issue will be faced by analyzing, on the one hand, the standards that guide the food system in the world and, on the other hand, human rights indicators whose purpose is to provide an effective monitoring of the State's obligations to guarantee food security, analyzing the implications of the former for the success of the latter. The methodology adopted in this article was bibliographic-documentary and consists of three moments of analysis. The first moment consists in the analysis of the reports of the Commission on Human Rights of the Organization of American States to identify the set of progress indicators developed by the Commission. This analysis will involve the new methodology used to evaluate the efficiency in monitoring food security in Brazil the case of using pesticides in the production of food at levels of toxicity not admitted by the inspection bodies. The second moment consists in evaluating the mechanism for monitoring food security in Brazil, which was initially established by the National Food Security Plan (PLANSAN) for 2012-2015 and improved by the II National Food Security Plan for 2016-2019. Those mechanisms were prepared by the Chamber (CAISAN), and have the function to compare the monitoring proposals with the results presented by CAISAN on the Indicators and Results Report of the National Plan for Food and Nutrition Security 2012-2015. The third moment was intended to understand, analyze and evaluate the standardization process of the agri-food system, especially regarding the level of toxicity standards, that is related to food safety monitoring as a guarantee of pesticide-free food. The results show the dependence between private standards of toxicity and the indicators of food safety that leads to inefficiency on monitoring that mechanism in Brazil.

Keywords: standards, indicators, human rights, food security

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Authors: D. Zahran, M. AlKhazindar, M. Khalil, E. T. A. Sayed

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Streptomyces scabies is a pathogenic actinomycete that infects potato crop causing severe production losses. Actinophages affect the composition and diversity of the bacterial population, thereby, can be used as a biological control. Samples of actinomycetes and phages were collected from different cultivated soils including farms of Faculty of Science, Faculty of Agriculture and different locations in Giza, Egypt. Actinomycetes were identified by using biochemical, morphological tests and molecular studies using 16S rRNA sequencing. Two specific phages (E1 and E2) against Streptomyces scabies and other hosts were isolated. Phages were identified using dilution end point (DEP), longevity in vitro (LIV), thermal inactivation point (TIP), host range and electron microscopy. PhageE1 was characterized by 10-8 (DEP),180 days(LIV), 95°C(TIP), narrow host range and electron microscopy showed ahead (59.9 nm) and neck (10.4nm). On the other hand phageE2 had 10-20 (DEP),180 days(LIV), 90°C(TIP), and the size of head was (67.2 nm) and tail (114nm). Antiviral activity was also studied using different chemicals (NaCL, KCL, CaCL2, BaCL2, CoCL2, AgNO3, ALCL3and HgCL2) with different concentrations and different plant extracts with different concentrations (star anise, tea, tillia, peppermint, ginger, cumin, chamomile, turmeric cinnamon, marjoram and black cumin). Both Phage E1and phage E2 were vulnerable to (cumin, ginger, chamomile, guavas leaves and star anise) but resistant to (Tillie, marjoram, fennelflower seeds, peppermint, and cinnamon).

Keywords: potato scab, actinophages, biological control, electron microscopy, TIP, DEP, LIV, antiviral activity

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Authors: Galiya Zhanzakovna Alzhanova, Yelaman Kanatovich Aibuldinov, Zhanar Baktybaevna Iskakova, Gaziz Galymovich Abdiyussupov, Madi Toktasynuly Omirzak, Aizhan Doldashevna Gazizova

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The sustainable use of industrial waste has recently increased due to increased environmental problems in landfills. One of the best ways to utilise waste is as a road base material. Industrial waste is a less costly and more efficient way to strengthen local soils than by introducing new additive materials. This study explored the feasibility of utilising red mud, blast furnace slag, and lime production waste to develop environmentally friendly construction materials for stabilising natural loam. Four different ratios of red mud (20, 30, and 40%), blast furnace slag (25, 30, and 35%), lime production waste (4, 6, and 8%), and varied amounts of natural loam were combined to produce nine different mixtures. The results showed that the sample with 40% red mud, 35% blast furnace slag, and 8% lime production waste had the highest strength. The sample's measured compressive strength for 90 days was 7.38 MPa, its water resistance for the same period was 7.12 MPa, and its frost resistance for the same period was 7.35 MP; low linear expansion met the requirements of the Kazakh regulations for first-class building materials. The study of mineral composition showed that there was no contamination with heavy metals or dangerous substances. Road base materials made of red mud, blast furnace slag, lime production waste, and natural loam mix can be employed because of their durability and environmental performance. The chemical and mineral composition of raw materials was determined using X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive spectroscopy, atomic absorption spectroscopy, and axial compressive strength were examined.

Keywords: blast furnace slag, lime production waste, natural loam stabilizing, red mud, road base material

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Authors: Rashad R. Al-Hindi

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The aim of this study was to isolate and identify lactic acid bacteria and evaluate their therapeutic and food preservation importance. Ninety-three suspected lactic acid bacteria (LAB) were isolated from thirteen different raw and fermented milk of indigenous sources in the Kingdom of Saudi Arabia. The identification of forty-six selected LAB strains and genetic relatedness were performed based on 16S rDNA gene sequence comparison. The LAB counts in certain samples were higher under microaerobic than anaerobic conditions. The identified LAB belonged to genera Enterococcus (16 strains), Lactobacillus (9 strains), Weissella (10 strains), Streptococcus (8 strains) and Lactococcus (3 strains). Phylogenetic tree generated from the full-length (~1.6 kb) sequences confirmed previous findings. Utilization of shorter 16S rDNA sequences (~1.0 kb) also discriminated among strains of which V2 region was the most effective. None of the strains exhibited resistance to clinically relevant antibiotics or undesirable hemolytic activity, while they differed in other probiotic characteristics, e.g., tolerance to acidic pH, resistance to bile salt, and antibacterial activity. In conclusion, the isolates Lactobacillus casei MSJ1, Lactobacillus casei Dwan5, Lactobacillus plantarum EyLan2 and Enterococcus faecium Gail-BawZir8 are likely the best probiotic LAB and we speculate that studying the synergistic effects of bacterial combinations might result in the occurrence of more effective probiotic potential. We argue that the raw and fermented milk of animals hosted in Saudi Arabia, especially stirred yogurt (Laban) made from camel milk, are rich in LAB with promising probiotics potential.

Keywords: fermented foods, lactic acid bacteria, probiotics, Saudi Arabia

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Authors: Juliana Janet R. Martin-Puzon, Demetrio L. Valle, Windell L. Rivera

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This study aimed to determine the presence of bioactive phytochemical constituents and evaluate the in vitro antibacterial activities of Glinus oppositifolius or carpet weed, a plant valued for its use in traditional medicine and as a vegetable. The leaves, stems, and roots were extracted using chloroform, ethanol, and methanol. Phytochemical screening revealed that the entire G. oppositifolius plant, i.e. roots, stems, and leaves, is a rich source of alkaloids, flavonoids, glycosides, saponins, sterols, tannins, and triterpenes. The antibacterial activity of the leaf and stem extracts were evaluated through disc diffusion, minimum inhibitory concentration, and bactericidal concentration assays against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), extended spectrum β-lactamase-producing (ESβL+), carbapenem-resistant Enterobacteriaceae (CRE), and metallo-β-lactamase-producing (MβL+) Pseudomonas aeruginosa and Acinetobacter baumannii. The leaf extracts revealed antibacterial activities, inhibiting the growth of non-resistant and multidrug-resistant (MDR) strains of the Gram-negative bacteria E. coli, P. aeruginosa, and A. baumanii. In conclusion, the various biological activities of G. oppositifolius, including its antibacterial activity, are due to the presence of diverse bioactive secondary metabolites. The presence of phytochemical compounds in G. oppositifolius is scientific evidence on its use for treatment of many ailments. Thus, the results demonstrate the great potential of the plant as a new, alternative source of antimicrobials and other components with therapeutic value.

Keywords: antibacterial, Glinus oppositifolius, multidrug-resistant, secondary metabolites

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Authors: Klytaimnistra Katsara, George Kenanakis, Eleftherios Alissandrakis, Vassilis M. Papadakis

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In recent decades, microplastics (MPs) attracted the interest of the research community as the level of environmental plastic pollution has increased over the years. Through air inhalation and food consumption, MPs enter the human body, creating a series of possible health issues. The majority of MPs enter through the digestive tract; they migrate from the plastic packaging of the foodstuffs. Several plastics, such as Polyethylene (PE), are commonly used as food packaging material due to their preservation and storage capabilities. In this work, the surfaces of three different cured meat products with varied fat compositions were studied (bacon, mortadella, and salami) to determine the migration of MPs from plastic packaging. Micro-Raman spectroscopic measurements were performed in an experimental set lasting 28 days, where the meat samples were stored in vacuum-sealed low-density polyethylene (LDPE) pouches under refrigeration conditions at 4°C. Specific measurement days (0, 3, 9, 12, 15, and 28 days of storage) were chosen to obtain comparative results. Raman micro-spectroscopy was used to monitor the MPs migration, where the Raman spectral profile of LDPE first appeared on day 9 in Bacon, day 15 in Salami, and finally, on day 28 in Mortadella. All the meat samples on day 28 were tainted because a layer of bacterial outgrowth had developed on their surface. In conclusion, MP migration from food packaging to the surface of the cured meat samples was proven. To minimize the consumption of MPs in cured meat products that are stored in plastic packaging, a short period of storage time under refrigeration conditions is advised.

Keywords: cured meat, food packaging, low-density polyethylene, microplastic migration, micro-Raman spectroscopy

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Authors: Abdulrahman Abdulhamid Arabo, Raji Arabi Bamanga, Mujiburrahman Fadilu, Musa Abubakar, Fatima Abdullahi Shehu, Hafeez Muhammad Yakasai, Nasiru Abdullahi

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The aim of this study was to isolate and identify biosurfactant-producing and diesel alkanes degrading bacteria. For this reason, bacteria isolated from the diesel-contaminated site were screened for their potential to produce biosurfactants and degrade diesel alkanes. Primary selection of diesel degraders was carried out by using the conventional enrichment culture technique, where 12 bacterial strains were isolated based on their ability to grow on minimal media supplemented with diesel as the sole carbon source, which was followed by qualitative screening methods for potential biosurfactant production. Isolate B11 was the only candidate that showed positive signs for drop collapse, foaming, hemolytic test, oil displacement of more than 22 ± 0.05 mm, and emulsification (E24) of 14 ± 0.30%. The effect of various culture parameters (incubation time, diesel concentration, nitrogen source, pH and temperature) on the biodegradation of diesel was evaluated. The optimum incubation time was confirmed to be 120 days for isolate B11, and the optimum PH was confirmed as 8.0 for the isolate; similarly, the optimum temperature was confirmed as 35oC. In addition, diesel oil was used as the sole carbon source for the isolates. The favorable diesel concentration was 12.5 % (v/v) for the isolate. The isolate has shown degradative ability towards Tridecane (C13), dodecane, 2, 6, 10-trimethyl- (C15), Tetradecane (C14), 2,6,10-Trimethyltridecane (C16), Pentadecane (C15). It degraded between 0.27% - 9.65% of individual diesel oil alkanes. The strain has exhibited the potential of degrading diesel oil n-alkanes and was identified as Alcaligenes species strain B11 (MZ027604) using the 16S rRNA. Sequencing.

Keywords: diesel oil, biosurfactant, Alcaligenes sp, biodegradation

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Authors: Hinda Berghiche, Hamida Benradia, Noureddine Soltani

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Pesticides are widely used in crop production and are known to induce a major contamination of ecosystems especially in aquatic environments. The leaching of a large amount of pollutants derived from agricultural activities (fertilizers, pesticides) might contaminate rivers which diverse into the likes and estuarine and coastal environments affecting several organisms such as crustacean species. In this context, there is searched for new selective insecticides with minimal toxic effects on the environment and human health such as growth insect regulators (GIRs). The current study aimed to examine the impact of novaluron (CE 20%), a potent benzoylphenylurea derivative insecticide on mosquito larvae, against non-target shrimp, Palaemon adspersus (Decapoda, Palaemonidae). The compound was tested at two concentrations (0.91 mg/L and 4.30 mg/L) corresponding respectively to the LC50 and LC90 determined against fourth-instar larvae of Culiseta longiareolata (Diptera, Culicidae). The molting hormone titer was determined in the haemolymph by an enzyme-immunoassay, while chitin was measured in peripheral integument at different stages during the molting cycle. Under normal conditions, the haemolymphatic ecdysteroid concentrations increased during the molting cycle to reach peak at stage D. In the treated series, we note absence of the peak at stage D and an increase at stages B, C and D as compared to the controls. Concerning the chitin amounts, we observe an increase from stage A to stage C followed by a decrease at stage D. Exposition of shrimps to novaluron resulted in a significant decrease of values at all molting stages with a dose-response effect. Thus, the insecticide can present secondary effects on this non-target arthropod species.

Keywords: toxicology, novaluron, crustacean, palaemon adspersus, ecdysteroids, cuticle, chitin

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Authors: Muhammad Imran Nisar, Fyezah Jehan, Tauseef Akhund, Sadia Shakoor, Kanwal Nayani, Furqan Kabir, Asad Ali, Anita Zaidi

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Pneumococcal Vaccine -10 (PCV 10) was included in the Expanded Program of immunization (EPI) in Sindh, Pakistan in February 2013. This study was carried out immediately before the introduction of PCV 10 to establish baseline pneumococcal carriage and prevalent serotypes in naso-pharynx of children 3-11 months of age in an urban and rural community in Sindh, Pakistan. An additional sample of children aged 12 to 59 months was drawn from the urban community. Nasopharyngeal specimens were collected from a random sample of children. Samples were processed in a central laboratory in Karachi. Pneumococci were cultured on 5% Sheep Blood Agar and serotyping was performed using CDC standardized sequential multiplex PCR assay on bacterial colonies. Serotypes were then categorized into vaccine (PCV-10 and PCV-13) type and non-vaccine types. A total of 670 children were enrolled. Carriage rate for pneumococcus based on culture positivity was 74% and 79.5 % in the infant group in Karachi and Matiari respectively. Carriage rate was 78.2% for children aged 12 to 59 months in Karachi. Proportion of PCV 10 serotypes in infants was 38.8% and 33.5% in Karachi and Matiari respectively. In the older age group in Karachi, the proportion was 30.6%. Most common serotypes were 6A, 6B, 23F, 19A and 18C. This survey establishes vaccine and non-vaccine serotype carriage rate in a vaccine-naïve pediatric population among rural and urban communities in Sindh province. Annually planned surveys in the same communities will inform change in carriage rate after the introduction and uptake of PCV 10 in these communities.

Keywords: Naso-Pharyngeal carriage, Pakistan, PCV10, Pneumococcus

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Authors: Xiao L Dai, Wen X Wei, Shuo Wang, Jia B Li, Yan Wei

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Heavy oil pollution generated from both natural and anthropogenic sources could cause significant damages to the ecological environment, due to the toxicity of some of its constituents. Nowadays, microbial remediation is becoming a promising technology to treat oil pollution owing to its low cost and prevention of secondary pollution; microorganisms are key players in the process. Compared to the free microorganisms, immobilized microorganisms possess several advantages, including high metabolic activity rates, strong resistance to toxic chemicals and natural competition with the indigenous microorganisms, and effective resistance to washing away (in open water system). Many immobilized microorganisms have been successfully used for bioremediation of heavy oil pollution. Considering the broad choices, low cost, simple process, large specific surface area and less impact on microbial activity, modified zeolite were selected as a bio-carrier for bacteria immobilization. Three strains of heavy oil-degrading bacteria Bacillus sp. DL-13, Brevibacillus sp. DL-1 and Acinetobacter sp. DL-34 were immobilized on the modified zeolite under mild conditions, and the bacterial load (bacteria /modified zeolite) was 1.12 mg/g, 1.11 mg/g, and 1.13 mg/g, respectively. SEM results showed that the bacteria mainly adsorbed on the surface or punctured in the void of modified zeolite. The heavy oil degradation efficiency of immobilized bacteria was 62.96%, higher than that of the free bacteria (59.83%). The heavy oil degradation process of immobilized bacteria accords with the first-order reaction equation, and the reaction rate constant is 0.1483 d⁻¹, which was significantly higher than the free bacteria (0.1123 d⁻¹), suggesting that the immobilized bacteria can rapidly start up the heavy oil degradation and has a high activity of heavy oil degradation. The results suggested that immobilized bacteria are promising technology for bioremediation of oil pollution.

Keywords: heavy oil pollution, microbial remediation, modified zeolite, immobilized bacteria

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Authors: K. Hinde, R. Bookun, P. Tran

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Percutaneous CT guided biopsies provide a fast, minimally invasive, cost effective and safe method for obtaining tissue for histopathology and culture. Standards for diagnostic yield vary depending on whether the tissue is being obtained for histopathology or culture. We present a retrospective audit from Western Health in Melbourne Australia over a 12-month period which aimed to determine the diagnostic yield, technical success and complication rate for CT guided bone biopsies and identify factors affecting these results. The digital imaging storage program (Synapse Picture Archiving and Communication System – Fujifilm Australia) was analysed with key word searches from October 2015 to October 2016. Nineteen CT guided bone biopsies were performed during this time. The most common referring unit was oncology, work up imaging included CT, MRI, bone scan and PET scan. The complication rate was 0%, overall diagnostic yield was 74% with a technical success of 95%. When performing biopsies for histologic analysis diagnostic yield was 85% and when performing biopsies for bacterial culture diagnostic yield was 60%. There was no significant relationship identified between size of lesion, distance of lesion to skin, lesion appearance on CT, the number of samples taken or gauge of needle to diagnostic yield or technical success. CT guided bone biopsy at Western Health meets the standard reported at other major clinical centres for technical success and safety. It is a useful investigation in identification of primary malignancy in distal bone metastases.

Keywords: bone biopsy, computed tomography, core biopsy, histopathology

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Authors: George Abu-Aqil, Leah Tsror, Elad Shufan, Shaul Mordechai, Mahmoud Huleihel, Ahmad Salman

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Pectobacterium and Dickeya spp which negatively affect a wide range of crops are the main causes of the aggressive diseases of agricultural crops. These aggressive diseases are responsible for a huge economic loss in agriculture including a severe decrease in the quality of the stored vegetables and fruits. Therefore, it is important to detect these pathogenic bacteria at their early stages of infection to control their spread and consequently reduce the economic losses. In addition, early detection is vital for producing non-infected propagative material for future generations. The currently used molecular techniques for the identification of these bacteria at the strain level are expensive and laborious. Other techniques require a long time of ~48 h for detection. Thus, there is a clear need for rapid, non-expensive, accurate and reliable techniques for early detection of these bacteria. In this study, infrared spectroscopy, which is a well-known technique with all its features, was used for rapid detection of Pectobacterium and Dickeya spp. at the strain level. The bacteria were isolated from potato plants and tubers with soft rot symptoms and measured by infrared spectroscopy. The obtained spectra were analyzed using different machine learning algorithms. The performances of our approach for taxonomic classification among the bacterial samples were evaluated in terms of success rates. The success rates for the correct classification of the genus, species and strain levels were ~100%, 95.2% and 92.6% respectively.

Keywords: soft rot enterobacteriaceae (SRE), pectobacterium, dickeya, plant infections, potato, solanum tuberosum, infrared spectroscopy, machine learning

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Authors: Sean T. S. Wei, Joy D. Van Nostrand, Annapoorna Maitrayee Ganeshram, Stephen B. Pointing

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McMurdo Dry Valleys are a largely ice-free polar desert protected by international treaty as an Antarctic special managed area. The terrestrial landscape is dominated by oligotrophic mineral soil with extensive rocky outcrops. Several environmental stresses: low temperature, lack of liquid water, UV exposure and oligotrophic substrates, restrict the major biotic component to microorganisms. The bacterial diversity and the putative physiological capacity of microbial communities of quartz rocks (hypoliths) and soil of a maritime-influenced Dry Valleys were interrogated by two metagenomic approaches: 454 pyro-sequencing and Geochp DNA microarray. The most abundant phylum in hypoliths was Cyanobacteria (46%), whereas in solils Actinobacteria (31%) were most abundant. The Proteobacteria and Bacteriodetes were the only other phyla to comprise >10% of both communities. Carbon fixation was indicated by photoautotrophic and chemoautotrophic pathways for both hypolith and soil communities. The fungi accounted for polymer carbon transformations, particularly for aromatic compounds. The complete nitrogen cycling was observed in both communities. The fungi in particular displayed pathways related to ammonification. Environmental stress response pathways were common among bacteria, whereas the nutrient stress response pathways were more widely present in bacteria, archaea and fungi. The diversity of bacterialphage was also surveyed by Geochip. Data suggested that different substrates supported different viral families: Leviviridae, Myoviridae, Podoviridae and Siphoviridiae were ubiquitous. However, Corticoviridae and Microviridae only occurred in wetter soils.

Keywords: Antarctica, hypolith, soil, dry valleys, geochip, functional diversity, stress response

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Authors: Majid Javanmard

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Edible mushrooms are those agricultural products which contain high quantity of protein and can have special role in human diet. So search for methods to increase their shelf life is important. One of these strategies can be use of active packaging for absorb the ethylene which has been studied in present study. In this study, initially, production of impregnating zeolite with potassium permanganate has been studied with zeolite clinoptiolite available in iran. After that, these ethylene scavengers were placed in the package of edible mushrooms and then transferred to the refrigerator with temperature 4c for a period of 20 days. Each 5 days, several experiments accomplished on edible mushrooms such as weight loss, moisture content, color, texture, bacterial experiments and sensory evaluation. After production of impregnating zeolite with potassium permanganate (with a concentration of %2.5, %5, %7.5, %10 and %12.5) by zeolite type clinoptiolite (with mesh 35 and 60), samples have been analyzed with gas chromatography and titration with sodium oxalate. The results showed that zeolite by concentration of %5, %7.5 and %10 potassium permanganate and mesh 60 have a higher efficiency. Results from the experiments on edible mushrooms proved that impregnated zeolite with potassium permanganate have a meaningful influence in prevent the weight loss, decrease of moisture content and L-value, increase of a-value and overall color change (ΔE) and decrease of firmness texture of mushrooms. In addition, these absorbents can influence on decrease microbial load (mesophilic bacteria) rather than control. Generally, concluded that the impregnated zeolite with 10% permanganate potassium has a high efficiency on increase the shelf life of fresh edible mushrooms.

Keywords: active packaging, ethylene scavenger, zeolite clinoptiolite, permanganate potassium, shelf life

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Authors: Preeyarach Whisetkhan, Malai Taweechotipatr, Ulisa Pachekrepapol

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Elevated level of blood cholesterol or hypercholesterolemia may lead to atherosclerosis and poses a major risk for cardiovascular diseases. Probiotics play a crucial role in human health, and probiotic bacteria that possesses bile salt hydrolase (BSH) activity can be used to lower cholesterol level of the host. The aim of this study was to investigate whether lactic acid bacteria (LAB) isolated from traditional Thai fermented foods were able to exhibit bile salt hydrolase activity and their use in fermented milk. A total of 28 isolates were tested for BSH activity by plate method on MRS agar supplemented with 0.5% sodium salt of taurodeoxycholic acid and incubated at 37°C for 48 h under anaerobic condition. The results showed that FN1-1 and FN23-3 isolates possessed strong BSH activity. FN1-1 and FN23-3 isolates were then identified for phenotype, biochemical characteristics, and genotype (16S rRNA sequencing). FN1-1 isolate showed 99.92% similarity to Lactobacillus pentosus DSM 20314(T), while FN23-3 isolate showed 99.94% similarity to Enterococcus faecium CGMCC1.2136 (T). Lactobacillus pentosus FN1-1 and Enterococcus faecium FN23-3 were tolerant of pH 3-4 and 0.3 and 0.8% bile. Bacterial count and pH of milk fermented with Lactobacillus pentosus FN1-1 at 37°C and 43°C were investigated. The results revealed that Lactobacillus pentosus FN1-1 was able to grow in milk, which led to decrease in pH level. Fermentation at 37°C resulted in faster growth rate than at 43 °C. Lactobacillus pentosus FN1-1 was a candidate probiotic to be used in fermented milk products to reduce the risk of high-cholesterol diseases.

Keywords: probiotics, lactic acid bacteria, bile salt hydrolase, cholesterol

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Authors: Adebowale T. Odeyemi, Oluwafemi A. Ajenifuja

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The leachate samples collected from Erifun dumpsite along Federal Polythenic road, Ado-Ekiti, Ekiti State, were subjected to bacteriological and mineral analyses. The bacteriological estimation and isolation were done using serial dilution and pour plating techniques. Antibiotic susceptibility test was done using agar disc diffusion technique. Atomic Absorption Spectophotometry method was used to analyze the heavy metal contents in the leachate samples. The bacterial and coliform counts ranged from 4.2 × 105 CFU/ml to 2.97 × 106 CFU/ml and 5.0 × 104 CFU/ml to 2.45 x 106 CFU/ml, respectively. The isolated bacteria and percentage of occurrence include Bacillus cereus (22%), Enterobacter aerogenes (18%), Staphylococcus aureus (16%), Proteus vulgaris (14%), Escherichia coli (14%), Bacillus licheniformis (12%) and Klebsiella aerogenes (4%). The mineral value ranged as follow; iron (21.30mg/L - 25.60mg/L), zinc (1.80mg/L - 5.60mg/L), copper (1.00mg/L - 2.60mg/L), chromium (0.50mg/L - 1.30mg/L), candium (0.20mg/L - 1.30mg/L), nickel (0.20mg/L - 0.80mg/L), lead (0.05mg/L-0.30mg/L), cobalt (0.03mg/L - 0.30mg/L) and in all samples manganese was not detected. The entire organisms isolated exhibited a high level of resistance to most of the antibiotics used. There is an urgent need for awareness to be created about the present situation of the leachate in Erifun, on the need for treatment of the nearby stream and other water sources before they can be used for drinking and other domestic use. In conclusion, a good method of waste disposal is required in those communities to prevent leachate formation, percolation, and runoff into water bodies during the raining season.

Keywords: antibiotic susceptibility, dumpsite, bacteriological analysis, heavy metal

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Authors: Benselama Amel, Ounane S. Mohamed, Bekki Abdelkader

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A collection of 20 isolates from fresh Nodules of the legume plant Lablab purpureus was isolated. These isolates have been authenticated by seedling inoculation grown in jars containing sand. The results obtained after two months of culture have revealed that the 20 isolates (100% of the isolates) are able to nodulate their host plants. The results obtained were analyzed statistically by ANOVA using the software statistica and had shown that the effect of the inoculation has significantly improved all the growth parameters (the height of the plant and the dry weight of the aerial parts and roots, and the number of nodules). We have evaluated the tolerance of all strains of the collection to the major stress factors as the salinity, pH and extreme temperature. The osmotolerance reached a concentration up to 1710mm of NaCl. The strains were also able to grow on a wide range of pH, ranging from 4.5 to 9.5, and temperature, between 4°C and 40°C. Also, we tested the effect of the acidity, aluminum and ferric deficit on the Lablab-rhizobia symbiosis. Lablab purpureus has not been affected by the presence of high concentrations of aluminum. On the other hand, iron deficiency has caused a net decrease in the dry biomass of the aerial part. The results of all the phenotypic characters have been treated by the statistical Minitab software, the numerical analysis had shown that these bacterial strains are divided into two distinct groups at a level of similarity of 86 %. The SDS-PAGE was carried out to determine the profile of the total protein of the strains. The coefficients of similarity of polypeptide bands between the isolates and strains reference (Bradyrhizobium, Mesorizobium sp.) confirm that our strain belongs to the groups of rhizobia.

Keywords: SDS-PAGE, rhizobia, symbiosis, phenotypic characterization, Lablab purpureus

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Authors: Sameh A. S. Thabit Alariqi

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Food is widely packaged with plastic materials to prevent microbial contamination and spoilage. Ionizing radiation is widely used to sterilize the food-packaging materials. Sterilization by γ-radiation causes degradation for the plastic packaging materials such as embrittlement, stiffening, softening, discoloration, odour generation, and decrease in molecular weight. Many antioxidants can prevent γ-degradation but most of them are toxic. The migration of antioxidants to its environment gives rise to major concerns in case of food packaging plastics. In this attempt, we have aimed to utilize synergistic mixtures of stabilizers which are approved for food-contact applications. Ethylene-propylene-diene terpolymer (EPDM) have been melt-mixed with hindered amine stabilizers (HAS), phenolic antioxidants and organo-phosphites (hydroperoxide decomposer). Results were discussed by comparing the stabilizing efficiency of mixtures with and without phenol system. Among phenol containing systems where we mostly observed discoloration due to the oxidation of hindered phenol, the combination of secondary HAS, tertiary HAS, organo-phosphite and hindered phenol exhibited improved stabilization efficiency than single or binary additive systems. The mixture of secondary HAS and tertiary HAS, has shown antagonistic effect of stabilization. However, the combination of organo-phosphite with secondary HAS, tertiary HAS and phenol antioxidants have been found to give synergistic even at higher doses of -sterilization. The effects have been explained through the interaction between the stabilizers. After γ-irradiation, the consumption of oligomeric stabilizer significantly depends on the components of stabilization mixture. The effect of the organo-phosphite antioxidant on the overall stability has been discussed.

Keywords: ethylene-propylene-diene terpolymer, synergistic mixtures, gamma sterilization, gamma stabilization

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Authors: Adila Shaukat, Hussam Al Soub, Muna Al Maslamani, Abdullatif Al Khal

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Background: The aim of this study was to assess clinical presentation and antimicrobial susceptibility of Streptococcus (S.) anginosus group infections in Hamad General Hospital, a tertiary care hospital in the state of Qatar, which is a multinational community. The S. anginosus group is a subgroup of viridans streptococci that consist of 3 different species: S. anginosus, S. constellatus, and S. intermedius. Although a part of the human bacteria flora, they have potential to cause suppurative infections. Method: We studied a total of 101 patients with S. anginosus group infections from January 2006 until March 2012 by reviewing medical records and identification of organisms by VITEK 2 and MALDI-TOF. Results: The most common sites of infection were skin and soft tissue, intra-abdominal, and bacteremia (28.7%, 24.8%, and 22.7%, respectively). Abscess formation was seen in approximately 30% of patients. Streptococcus constellatus was the most common isolated species (40%) followed by S. anginosus(30%) and S. intermedius(7%). In 23% of specimens, the species was unidentified. The most common type of specimen for organism isolation was blood followed by pus and tissue (50%, 22%, and 8%, respectively). Streptococcus constellatus was more frequently associated with abdominal and skin and soft tissue infections than the other 2 species, whereas S. anginosus was isolated more frequently from blood. All isolates were susceptible to penicillin, ceftriaxone, and vancomycin. Susceptibility to erythromycin and clindamycin was also good, reaching 91% and 95%, respectively. Forty percent of patients needed surgical drainage along with antibiotic therapy. Conclusions: Identification of S. anginosus group to species level is helpful in clinical practice because different species exhibit different pathogenic potentials.

Keywords: abscess, bacterial infection, bacteremia, Streptococcus anginosus

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Authors: Ngonidzashe Mangoma, Caroline Marigold Sebata

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The release of cyanide-rich effluents from gold mines, and other industries, into the environment, is a global concern considering the well-known metabolic effects of cyanide in all forms of life. Such effluents need to be treated to remove cyanide, among other pollutants, before their disposal. This study aimed at investigating the possible use of bacteria in the biological removal of cyanide from cyanide-rich effluents. Firstly, cyanide-degrading bacteria were isolated from gold mine effluents and characterised. The isolates were then tested for their ability to grow in the presence of cyanide and their tolerance to increasing levels of the compound. To evaluate each isolate’s cyanide-degrading activities, isolates were grown in the simulated and actual effluent, and a titrimetric method was used to quantify residual cyanide over a number of days. Cyanide degradation efficiency (DE) was then calculated for each isolate. Identification of positive isolates involved 16S rRNA gene amplification and sequence analysis through BLAST. Six cyanide-utilising bacterial strains were isolated. Two of the isolates were identified as Klebsiella spp. while the other two were shown to be different strains of Clostridium bifermentans. All isolates showed normal growth in the presence of cyanide, with growth being inhibited at 700 mg/L cyanide and beyond. Cyanide degradation efficiency for all isolates in the simulated effluent ranged from 79% to 97%. All isolates were able to remove cyanide from actual gold mine effluent with very high DE values (90 – 94%) being recorded. Isolates obtained in this study were able to efficiently remove cyanide from both simulated and actual effluent. This observation clearly demonstrates the feasibility of the biological removal of cyanide from cyanide-rich gold mine effluents and should, therefore, motivate research towards the possible large-scale application of this technology.

Keywords: cyanide effluent, bioremediation, Clostridium bifermentans, Klebsiella spp, environment

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Authors: Konstans Ruseva, Kristina Ivanova, Katerina Todorova, Margarita Gabrashanska, Tzanko Tzanov, Elena Vassileva

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Zwitterionic polymers (ZP) are well-known with their ultralow biofouling. They are successfully competing with poly(ethylene glycols) (PEG), which are considered as the “golden standard” in this respect. These unique properties are attributed to their strong hydration capacity, defined by the dipole-dipole interactions, arising between the ZP pendant groups as well as to the dipoles interaction with water molecules. Beside, ZP are highly resistant to bacterial adhesion thus ensuring an excellent anti-biofilm formation ability. Moreover, ZP are able to respond upon external stimuli such as temperature, pH, salt concentration changes which in combination with their anti-biofouling effect render this type of polymers as materials with a high potential in biomedical applications. The present work is focused on the development of zwitterionic hydrogels for efficient treatment of highly exudating and hard-to-heal chronic wounds. To this purpose, two types of ZP networks with different crosslinking degree were synthesized - polysulfobetaine (PSB) and polycarboxybetaine (PCB) ones. They were characterized in terms of their physico-mechanical properties, e.g. microhardness, swelling ability, smart behaviour. Furthermore, the potential of ZP networks to resist biofilm formation towards Staphylococcus aureus and Escherichia coli was studied. Their ability to reduce the high levels of myeloperoxidase and metalloproteinase, two enzymes that are part of the chronic wounds enviroenment, was revealed. Moreover, the in vitro cytotoxic assessment of PSB and PCB networks along with their in vivo performance in rats was also studied to reveal their high biocompatibility.

Keywords: absorption properties, biocompatibility, enzymatic inhibition activity, wound healing, zwitterionic polymers

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Authors: Yılmaz Uçar, Fatih Ozogul, Mustafa Durmuş, Yesim Ozogul, Ali Rıza Köşker, Esmeray Kuley Boğa, Deniz Ayas

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The aim of this study was to purified eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), that are essential oils from trout oil, using high-performance liquid chromatography (HPLC) method, bioconverted EPA and DHA into bioconverted EPA (bEPA), bioconverted DHA (bDHA) extracts by P. aeruginosa PR3. Moreover, in vitro antibacterial activity of bEPA and bDHA was investigated using disc diffusion methods and minimum inhibitory concentration (MIC). EPA and DHA concentration of 11.1% and 15.9% in trout oil increased in 58.64% and 40.33% after HPLC optimisation, respectively. In this study, EPA and DHA enriched products were obtained which are to be used as valuable supplements for food and pharmaceutical purposes. The bioconverted EPA and DHA exhibited antibacterial activities against two Gram-positive bacteria (Listeria monocytogenes ATCC 7677 and Staphylococcus aureus ATCC 29213) and six Gram-negative bacteria (Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC700603, Enterococcus faecalis ATCC 29212, Aeromonas hydrophila NCIMB 1135, and Salmonella Paratyphi A NCTC 13). Inhibition zones and MIC value of bEPA and bDHA against bacterial strains ranged from 7 to 12 mm and from 350 to 2350 μg/mL, respectively. Our results suggested that the crude extracts of bioconversion of EPA and DHA by P. aeruginosa PR3 can be considered as promising antimicrobials in improving food safety by controlling foodborne pathogens.

Keywords: High-Performance Liquid Chromatography (HPLC), docosahexaenoic acid, DHA, eicosapentaenoic acid, EPA, minimum inhibitory concentration, MIC, Pseudomonas aeruginosa PR3

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Authors: Ganesh K. Maurya, Reema Chaudhary, Neha Pandey, Hari S. Misra

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PprA, a pleiotropic protein participating in radioresistance, has been reported for its roles in DNA replication initiation, genome segregation, cell division and DNA repair in polyextremophile Deinococcus radiodurans. Interestingly, expression of deinococcal PprA in E. coli suppresses its growth by reducing the number of colony forming units and provides better resistance against γ-radiation than control. We employed different biochemical and cell biology studies using PprA and its DNA binding/polymerization mutants (K133E & W183R) in E. coli. Cells expressing wild type PprA or its K133E mutant showed reduction in the amount of genomic DNA as well as chromosome copy number in comparison to W183R mutant of PprA and control cells, which suggests the role of PprA protein in regulation of DNA replication initiation in E. coli. Further, E. coli cells expressing PprA or its mutants exhibited different impact on cell morphology than control. Expression of PprA or K133E mutant displayed a significant increase in cell length upto 5 folds while W183R mutant showed cell length similar to uninduced control cells. We checked the interaction of deinococcal PprA and its mutants with E. coli DnaA using Bacterial two-hybrid system and co-immunoprecipitation. We observed a functional interaction of EcDnaA with PprA and K133E mutant but not with W183R mutant of PprA. Further, PprA or K133E mutant has suppressed the ATPase activity of EcDnaA but W183R mutant of PprA failed to do so. These observations suggested that PprA protein regulates DNA replication initiation and cell morphology of surrogate E. coli.

Keywords: DNA replication, radioresistance, protein-protein interaction, cell morphology, ATPase activity

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