Methane is a powerful greenhouse gas but the microbial diversity mediating methylotrophic methanogenesis is not well-characterized. One overlooked route to methane is via the degradation of dimethylsulfide (DMS), an abundant organosulfur compound in the environment. Methanogens and sulfate-reducing bacteria (SRB) can degrade DMS in anoxic sediments depending on sulfate availability. However, we know little about the underlying microbial community and how sulfate availability affects DMS degradation in anoxic sediments. We studied DMS-dependent methane production along the salinity gradient of the Medway Estuary (UK) and characterized, for the first time, the DMS-degrading methanogens and SRB using cultivation-independent tools. DMS metabolism resulted in high methane yield (39%-42% of the theoretical methane yield) in anoxic sediments regardless of their sulfate content. Methanomethylovorans, Methanolobus and Methanococcoides were dominant methanogens in freshwater, brackish and marine incubations respectively, suggesting niche-partitioning of the methanogens likely driven by DMS amendment and sulfate concentrations. Adding DMS also led to significant changes in SRB composition and abundance in the sediments. Increases in the abundance of Sulfurimonas and SRB suggest cryptic sulfur cycling coupled to DMS degradation. Our study highlights a potentially important pathway to methane production in sediments with contrasting sulfate content and sheds light on the diversity of DMS degraders.

Objective: Almost all year round occurrence of typhoid fever remains a major public health issue in Bangladesh. In recent years, there has been a significant rise in the prevalence of multi-drug resistance Salmonella typhi in Dhaka city. The major objective of this study was to observe the prevalence of multi-drug and Extended drug-resistant patterns of typhoidal Salmonella typhi among the patients attending a tertiary medical center by conventional culture and serologic test. Materials and Methods: Blood was collected by syringe and equally divided between aerobic & anaerobic BacT Alert bottle, 10 mL for paediatrics. Post isolation Salmonella strains were identified and were tested for antibiotic resistance. Results: A total of 600 blood samples of typhoid suspected patients were tested, where 32.5% came out positive, which were identified as Salmonella typhi. These isolates were susceptible to carbapenem drugs but highly resistant to Fluoroquinolones and Aminoglycosides antibiotics. Discussion: It was seen that 73.23% of isolates among male patients were extensively drug-resistant (XDR) meaning that isolates were sensitive against only one or two antibiotics while in the female it was 58.46%. Isolates from Female patients showed higher multi-drug resistant (MDR) (26.15%) isolates resistance to multiple antibiotics in comparison to isolates from the male (16.54%). 87.19% of the strains showed high drug resistance (XDR and MDR). Conclusion: The emergence of XDR and MDR strains of S. typhi in recent years is becoming a significant threat. Although no PAN-Drug resistance (resistant against all tested drugs

This study was conducted to determine the microbiological quality of fresh raw and unwashed leafy and salad vegetables in Dhaka, Bangladesh. Six different types of samples (red amaranth, spinach, carrot, radish, tomato, and cucumber) were collected in pre-sterilized zip-lock bags from various local markets in Dhaka. All samples were transported to the Centre of Excellence for Global Health Research Laboratory of Primeasia University at earliest convenience. Samples were enriched in Nutrient Broth media and were then cultured on selective media for isolation purpose. Serial dilution was performed for the total viable count. Biochemical and carbohydrate profiling was conducted for the presumptive identification of the isolates. Commercial antibiotic discs were used for antibiogram by Kirby-Bauer disc diffusion method on Mueller-Hinton agar medium. The total microbial load ranged from 8x107 to 1.70x108. Total 36 isolates were identified, having 7 differentorganisms. The most predominant organism was Vibrio sp. (23%) followed by Klebsiella sp.(20%), Acinetobacter sp. (19%), Pseudomonas sp. (19%), Salmonella sp. (8%), Moraxella sp.(8%) and Escherichia coli (3%). 11% of the Vibrio sp. isolates were V. cholerae, found from 4 samples. No presence of V. cholerae was observed in the tomatosamples. E. coli was observed only in Carrot sample. Antibiotics from 7 different groups were tested against the organisms among which Imipenem showed the highest sensitivity (86%). Following Ceftriaxone (100%), Nitrofurantoin (94%), Erythromycin (89%) and Amoxicillin (83%) had the highest resistance against the isolated organisms. Moreover, most of the isolates showed a multi-drug resistance pattern where they were resistant to at least four drugs. Prevalence of pathogenic bacteria in raw unwashed vegetables can cause potential adverse health effects and therefore the consumers need to be conscious about the matter.

Fruits are highly nutritious, sources of vitamins, minerals, fibers etc. and these are part of our daily diet. However, during cultivation, harvesting, transportation, handling fruits get contaminated with pathogenic microorganisms which leads to severe problems to community. Owning to this point, in current research, bacteriological analysis was performed on Sofeda, Pineapple, Grape, Banana, Apple, Orange, Guava, papaya, Jujube and Starfruit. Total 50 samples were randomly collected from market and street vendors of Dhaka city. Higher numbers of rotten fruits were present in wholesale markets. 35 strains were isolated which included Salmonella spp., Acinetobacter spp., Klebsiella spp., Vibrio cholerae, Vibrio parahaemolyticus, Staphylocoous aureus and E. coli. They were identified using biochemical test and antibiogram for selective isolates. In case of drug resistance of isolates, majority exhibited resistance against Erythromycin, Vancomycin and Amoxycillin and showing sensitivity against Ciprofloxacin and Ceftriaxone. It was observed in the current study that 100% isolates were resistant against Erythromycin, followed by Amoxycillin 90.63% and vancomycin 86.25%, where only 35.27% isolates were resistant against Ciprofloxacin. In case of sensitivity 64.73% isolates were sensitive against Ciprofloxacin followed by Ceftriaxone 66.25%.