Characterization of multiple antibiotic resistance of culturable microorganisms and metagenomic analysis of total microbial diversity of marine fish sold in retail shops in Mumbai, India.

Marine fish species were analyzed for culturable and total metagenomic microbial diversity, antibiotic resistance (AR) pattern, and horizontal gene transfer in culturable microorganisms. We observed a high AR microbial load of 3 to 4 log CFU g. Many fish pathogens like Providencia, Staphylococcus, Klebsiella pneumoniae, Enterobacter, Vagococcus, and Aeromonas veronii were isolated.

Species specific PCR based detection of Escherichia coli from Indian foods.

Escherichia coli is a faecal indicator and certain virotypes are known as pathogens. Therefore, detection and prevention of E. coli in food is very important.

Cellular and spectroscopic characterization of cancer stem cell-like cells derived from A549 lung carcinoma.

Background: Cancer stem cells (CSCs) are increasingly being realized to play a significant role in the mechanism of chemo-, radio-resistance, and metastasis of cancer. However, studies for spectral markers of CSCs using Fourier transform infrared (FT-IR) and circular dichroism (CD) spectroscopy are limited in the literature.

Materials And Methods: In the present study, CSCs obtained from single cell assay of human lung adenocarcinoma (A549) cells were characterized using CD44+/CD24-/low phenotype expression, Hoechst 33342 dye efflux assay, and expression of stemness genes.

Expression of virulence and stress response genes in Aeromonas hydrophila under various stress conditions.

Aeromonas hydrophila has emerged as an important human pathogen as it causes gastroenteritis and extra-intestinal infections. Information regarding the influence of environmental stresses on gene expression profile of A. hydrophila is lacking.

Diverse Profiles of N-acyl Homoserine L-Lactones, Biofilm, Virulence Genes and Integrons in Food-Borne Aeromonas Isolates.

Aeromonas are regarded as opportunistic as well as primary pathogens of humans and fish, and are associated with gastroenteritis and septicemia in humans. Production of N-acyl-homoserine lactone (AHL) signal molecules and biofilm was determined in 22 Aeromonas isolates, from different food products in India, using thin-layer chromatography (TLC) analysis and microtiter-plate assay, respectively. Overall, highly heterogeneous patterns of AHL production were observed, with the production of N-butanoyl homoserine lactone (C4-HSL) and N-hexanoyl homoserine lactone (C6-HSL) by the majority (81.

Radiation-resistant Macrococcus caseolyticus (A) isolated from radiation-processed semidried prawns.

A radiation-resistant bacterial isolate from gamma-radiation-processed (5 kGy) semidried prawns was identified as a new strain of Macrococcus caseolyticus and was designated as M. caseolyticus (A) on the basis of morphological and biochemical characterization and 16S rRNA sequencing. DNA-DNA hybridization studies with M.

Induction, resuscitation and quantitative real-time polymerase chain reaction analyses of viable but nonculturable Vibrio vulnificus in artificial sea water.

Vibrio vulnificus, an important food-borne pathogen, is known to enter viable but nonculturable (VBNC) state under low temperature and low nutrition stress conditions. Present study examined the time required for induction of VBNC state and temperature which induces resuscitation of V. vulnificus YJ016.

Comparative analysis of induction of osmotic-stress-dependent genes in Vibrio vulnificus exposed to hyper- and hypo-osmotic stress.

Vibrio vulnificus, a halophilic pathogenic bacterium of marine environments, encounters changes in salinity in its natural habitat and in the food-processing environment. The comparative response of V. vulnificus to hyperosmotic and hypoosmotic stress in terms of gene expression was investigated.

Characterization of Aeromonas strains isolated from Indian foods using rpoD gene sequencing and whole cell protein analysis.

Aeromonas are responsible for causing gastroenteritis and extra-intestinal infections in humans. Twenty-two Aeromonas strains isolated from different food sources were re-identified up to species level using rpoD gene sequence analysis. Biochemical tests and 16S rRNA gene sequencing were insufficient to identify Aeromonas till species level.

Quantification of Salmonella in food samples from India using the MINI-MSRV MPN and modified MINI-MSRV MPN methods.

Salmonella is one of the most important food-borne pathogens. The MINI-MSRV MPN method was modified by replacing the isolation and confirmation of Salmonella on selective chromogenic agar with PCR/RT-PCR. This modification reduced the time for quantification by the MINI-MSRV MPN method by 24 h.

Prevalence, characterization, and antimicrobial resistance of Aeromonas strains from various retail food products in Mumbai, India.

A total of 154 food samples (chicken, fish, and ready-to-eat sprouts) from various retail outlets in Mumbai, India, were analyzed for the presence of Aeromonas spp. over a period of 2 y (January 2006 to March 2008). Twenty-two Aeromonas isolates belonging to 7 different species were isolated from 18 (11.

Evaluation of the role of enzymatic and nonenzymatic antioxidant systems in the radiation resistance of Deinococcus.

Antioxidant enzymes and antioxidant metabolites appear to have different roles in the oxidative stress resistance responses of radiation-resistant bacteria belonging to the Deinococcus-Thermus group. Twelve distinct strains belonging to 7 Deinococcus species were characterized for their responses to hydrogen peroxide, ciprofloxacin, and ionizing radiation. The levels of catalase and peroxidase activities in these strains showed a positive correlation with resistance to hydrogen peroxide and ciprofloxacin.

Gamma radiation used as hygienization technique for foods does not induce viable but non-culturable state (VBNC) in Salmonella enterica subsp. enterica serovar Typhimurium.

Gamma radiation has been widely used for hygienization of food products. Whether gamma radiation stress induces VBNC state in Salmonella is of great concern. Therefore, the study was carried out to determine whether gamma radiation exposure induces VBNC state in Salmonella enterica subsp.

Deinococcus piscis sp. nov., a radiation-resistant bacterium isolated from a marine fish.

A radiation-resistant, Gram-stain-positive, non-motile, non-sporulating, aerobic, coccoid bacterium, strain 3ax(T), was isolated from a marine fish (black pomfret, Parastromateus niger), with radiation as a selective pressure. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 3ax(T) exhibited highest similarity (97.9 %) with Deinococcus proteolyticus DSM 20540(T).

Radiation resistance of Deinococcus radiodurans R1 with respect to growth phase.

Deinococcus species exhibit an extraordinary ability to withstand ionizing radiation (IR). Most of the studies on radiation resistance have been carried out with exponential phase cells. The studies on radiation resistance of Deinococcus radiodurans R1 with respect to different phases of growth showed that late stationary phase cells of D.

Rapid, sensitive, and validated method for detection of Salmonella in food by an enrichment broth culture - nested PCR combination assay.

A rapid nested PCR assay for detection of Salmonella from food was developed. The sensitivity of the assay developed was comparable to the traditional culture based methods with an advantage in reduction of assay time. The assay procedure with artificially contaminated samples was able to detect as low as 4CFU Salmonella/25g of food samples (sprout, carrot, cucumber and poultry meat).

Distribution of Salmonella pathogenicity island (SPI)-8 and SPI-10 among different serotypes of Salmonella.

Many virulence phenotypes of Salmonella enterica are encoded by genes located on pathogenicity islands. Based on genome analysis, it is predicted that Salmonella pathogenicity island (SPI)-8 is restricted to Salmonella serovars Typhi and Paratyphi A, and SPI-10 to Salmonella serovars Typhi, Paratyphi, Enteritidis, Dublin and Gallinarum. This study was conducted to investigate the distribution of SPI-8 and SPI-10 among Salmonella isolates from sprouts, fish, water and blood.

Effectiveness of radiation processing for elimination of Salmonella Typhimurium from minimally processed pineapple (Ananas comosus Merr.).

The microbiological quality of market samples of minimally processed (MP) pineapple was examined. The effectiveness of radiation treatment in eliminating Salmonella Typhimurium from laboratory inoculated ready-to-eat pineapple slices was also studied. Microbiological quality of minimally processed pineapple samples from Mumbai market was poor; 8.

Radiation processing for elimination of Salmonella typhimurium from inoculated seeds used for sprout making in India and effect of irradiation on germination of seeds.

The effect of radiation processing on the germination of the sprout seeds mung (Phaseolus aureus), matki (Phaseolus aconitifolius), chana (Cicer arietinum), and vatana (Pisum sativum) in terms of percent germination, germination yield, sprout length, vitamin C content, and texture was investigated. Gradual decreases in the percent germination, germination yield, and sprout length with increases in radiation dose (0.5 to 2.

Serotyping, PCR, phage-typing and antibiotic sensitivity testing of Salmonella serovars isolated from urban drinking water supply systems of Nepal.

Aims: To study the occurrence and diversity of Salmonella serovars in urban water supply systems of Nepal.

Methods And Results: Occurrence of Salmonella was detected in 42 out of 300 water samples by enrichment culture technique in selenite F broth followed by plating on Salmonella Shigella agar. A total of 54 isolates identified to genus level by standard tests were subsequently confirmed by serotyping, phage typing and PCR detection of virulence genes (inv A and spv C).

Multiple-stress tolerance of ionizing radiation-resistant bacterial isolates obtained from various habitats: correlation between stresses.

Isolation of five ionizing radiation (IR)-resistant bacteria by screening of isolates from various habitats classified as common and stressed is reported. IR-resistant isolates exhibited varying degrees of resistance to gamma-radiation and were classified as highly and moderately radiation resistant. Resistance to ultraviolet (UV) radiation correlated well with gamma-radiation resistance, whereas a comparable desiccation resistance for all the highly and moderately radiation-resistant isolates was observed.

Microbiological evaluation of sprouts marketed in Mumbai, India, and its suburbs.

A study was undertaken to assess the microbiological quality of sprouts marketed in Mumbai and its suburbs. A total of 124 sprout samples of four different legumes--mung (Phaseolus aureus), matki (Phaseolus aconitifolius), chana (Cicer arietinum), and vatana (Pisum sativum)--were analyzed over a period of 12 months for aerobic plate counts, coliforms, yeast and mold counts, staphylococci, Salmonella, Listeria monocytogenes, Escherichia coli, E. coli O157:H7, and coagulase-positive Staphylococcus aureus.

Effectiveness of radiation processing in elimination of Salmonella typhimurium and Listeria monocytogenes from sprouts.

The effectiveness of radiation treatment in eliminating Salmonella Typhimurium and Listeria monocytogenes on laboratory inoculated ready-to-eat sprouts was studied. Decimal reduction doses (D10-values) for Salmonella Typhimurium and L. monocytogenes in dry seeds of mung (green gram), matki (dew gram), chana (chick pea), and vatana (garden pea) ranged from 0.

Radiation processing to ensure safety of minimally processed carrot (Daucus carota) and cucumber (Cucumis sativus): optimization of dose for the elimination of Salmonella Typhimurium and Listeria monocytogenes.

Minimally processed vegetables are in demand, because they offer convenience to consumers. However, these products are often unsafe because of possible contamination with pathogens, such as Salmonella, Escherichia coli O157:H7, and Shigella species. Therefore, this study was carried out to optimize the radiation dose necessary to ensure the safety of precut carrot and cucumber.