Department of Microbiology

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http://khandolacollege.ndl.gov.in/handle/123456789/43

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Browsing Department of Microbiology by Subject "NATURAL SCIENCES::Biology::Organism biology::Microbiology"

Now showing 1 - 4 of 4
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    Genotypic characterization of Listeria monocytogenes isolated from humans in India
    (Taylor & Francis, 2011) Kalekar, Sushanta; Rodrigues, Jenney; D'Costa, Dilecta; Doijad, Swapnil; Ashok Kumar, J; Malik, S. V. S; Kalorey, D. R; Hain, T; Chakraborty, T; Barbuddhe, Sukhadeo B.
    Listeria monocytogenes is a foodborne pathogen associated with severe diseases in humans and animals. The genotypic analysis of 17 L. monocytogenes isolates recovered from humans in India during 2006–2009 using multiplex serotyping PCR allowing serovar predictions, conventional serology and by pulsed field gel electrophoresis (PFGE) is presented. The isolates were recovered from patients exhibiting various clinical conditions. A multiplex-PCR based serotyping assay revealed 88·24% (15/17) of the strains belonging to the serovar group 4b, 4d, 4e and 11·76% (2/17) to the serovar group 1/2b, 3b. Conventional serology indicated that 13 (76·47%) L. monocytogenes isolates to be of serotype 4b, 2 (11·76%) serotype 4d, and 2 (11·76%) serotype 1/2b. Ten ApaI and nine AscI pulsotypes were recognized among the 17 human isolates. PFGE analysis allowed discrimination among isolates of the same serotype and among isolates from the same sampling areas or those isolated from different areas. Thus, PFGE together with multiplex-PCR serotyping allows rapid discrimination of L. monocytogenes strains. In addition, the predominance of L. monocytogenes serotype 4b is of concern, as this serotype has been most frequently associated with human listeriosis outbreaks.
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    Potability Testing of Drinking Water from Trains on Konkan Railway Route
    (TamilNadu Scientific Research Organisation, 2024) Rai, Anupkumar J.; D’Costa, Dilecta
    The availability of drinking water is one of the primary passenger amenities provided by the railways. The present study was undertaken to investigate and evaluate the water quality of the trains plying on the Konkan railway route. The physicochemical and microbiological studies were carried out to determine the potability of water supplied by railways. The isolation and phenotypic characterization of various pathogens were mainly emphasized. All the analyzed samples showed the presence of coliforms and other organisms indicative of fecal contamination. Seasonal analysis of microbial load indicated that monsoon favours the growth and proliferation of microbes. The biochemical assessment showed the presence of several pathogens like E. coli, Salmonella spp., Vibrio spp., and Clostridium spp. This is a matter of public health concern to train commuters which in turn calls for better sanitary measures.
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    Prevalence and characterisation of Listeria spp. from seafood
    (Indian Council of Agricultural Research, 2015) Rodrigues, Jenney; Kalekar, Sushanta; Doijad, Swapnil; Poharkar, Krupali; D'Costa, Dilecta; Barbuddhe, Sukhadeo B.
    Listeria monocytogenes, the causative organism of listeriosis, is primarily transmitted to humans through contaminated food. We examined the prevalence of L. monocytogenes isolates from fishery products marketed in Goa, India. A total of 221 raw seafood samples were examined for the presence of Listeria species following ISO 11290 protocol. Thirty seven (16.74%) samples were positive for Listeria species. Out of these, isolates from 4 (1.8%) samples were confirmed asL. monocytogenes, the remaining 33 isolates were Listeria innocua. All the isolates were subjected to PCR for the hlyAgene, which was detected in all the L. monocytogenes isolates. The isolates were also found to express phosphatidyl-inositol specific phospholipase C activity on ALOA agar. Multiplex PCR-based clonal typing revealed three L. monocytogenesisolates to be of serovar group 1/2a, 1/2c, 3a, 3c while the remaining isolates belonged to serovar group 1/2b, 3b 4b, 4d and 4e. The isolates were grouped into two AscI and ApaI PFGE (pulsed field gel electrophoresis) profiles. Prevalence ofL. monocytogenes in fresh seafood is of significance as it may contaminate and persist in the processing environment.
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    Rootstocks for the Management of Bacterial Wilt in Eggplant (Solanum melongena L.) and Tomato (Solanum lycopersicum L.) in the Coastal Regions of India
    (Hindawi, 2022) Ramesh, Raman; D’Souza, Marsha; Asolkar, Trupti; Achari, Gauri; Gupta, Mathala J.
    Cultivation of solanaceous vegetables such as eggplant and tomato is severely affected by bacterial wilt in the coastal regions of India. The causal agent Ralstonia pseudosolanacearum is soilborne bacterium, highly diverse, and able to survive in soil for many years without a host. Five bacterial wilt resistant eggplant (Solanum melongena) rootstock lines were evaluated by challenge inoculation and were found to show different levels of wilt incidence. Grafts of eggplant made on two rootstocks (S0004 and Surya) recorded reduced incidence of bacterial wilt (10 to 40%) during greenhouse evaluation while in nongrafted seedlings, the wilt incidence was 80 to 100%. Field evaluation of eggplant grafts made on Solanum torvum (Turkey berry), S0004, and Surya reduced the incidence of bacterial wilt compared to nongrafted seedlings. The lowest wilt incidence (0 and 15–40%) was observed in the field evaluations where S. torvum was used as rootstock, while the nongrafted control recorded 93–100% wilt. Tomato seedlings grafted on S. torvum, Surya, and S0004 recorded very low bacterial wilt incidence (0 to 15%) under greenhouse evaluation while the nongrafted seedlings recorded 80 to 100% wilt. Reduced bacterial wilt incidence (23 to 40%) was observed in grafts of polyhouse-grown tomato hybrid (GS-600) made on S. torvum while the nongrafted seedlings were severely affected (80 to 100%) in evaluation trials conducted for two years. From this study, it is evident that grafting of susceptible eggplant and tomato on resistant rootstocks, viz., S. torvum and Surya, could be a promising strategy in bacterial wilt management.