The occurrence of methicillin-resistant staphylococci was investigated in fresh seafood, seafood products and related samples. Staphylococci were isolated from 13 (68.42%) fresh seafood samples, while 3 (15.78%) sampl...The occurrence of methicillin-resistant staphylococci was investigated in fresh seafood, seafood products and related samples. Staphylococci were isolated from 13 (68.42%) fresh seafood samples, while 3 (15.78%) samples harbored coagulase-positive S. aureus. Resistance to methicillin was observed in 16 isolates of Staphylococcus spp., 15 of which were coagulase-negative S. aureus (MR-CoNS) and one was a coagulase-positive S. aureus (MRSA). The mecA gene is detected by PCR in 10 MR-CoNS and one MRSA strain. The lmrS gene, which codes for a multidrug efflux pump LmrS, is detected only in coagulase-positive isolates.展开更多
Histamine fish poisoning (HFP) is a major illness occurring throughout the world due to the consumption of quality of deteriorated fish containing pre-formed histamine from bacterial activities. In the study reported ...Histamine fish poisoning (HFP) is a major illness occurring throughout the world due to the consumption of quality of deteriorated fish containing pre-formed histamine from bacterial activities. In the study reported here, the histamine-producing bacteria were isolated from the muscle, gills and the gut of 19 samples of Indian mackerel (Rastrelliger kanagurta) from Mumbai, India. The isolates from modified Niven’s medium (MNM) were confirmed for their ability to produce histamine by using 4 different pH-indicator media, followed by HPLC analyses. Out of 202 isolates, 63 isolates produced considerable amounts of histamine on at least 3 out of 4 media used in this study. The histamine formers were identified by biochemical tests followed by sequencing of their 16SrDNA gene, which showed that 89% of the isolates belonged to 13 different genera of the family Enterobacteriaceae. The non-enterobacterial histamine-producing bacteria belonged to the genera Staphylococcus, Alkaligenes, Shewanella and Psychrobacter.展开更多
Adaptation of microbial communities to anthropogenic stress has often been shown to involve reduction in diversity and in selective enrichment of species capable of survival. The gut bacterial community of pollution-s...Adaptation of microbial communities to anthropogenic stress has often been shown to involve reduction in diversity and in selective enrichment of species capable of survival. The gut bacterial community of pollution-stressed polychaete Neanthes chilkaensis was studied using cultivation dependent and independent approaches. The possible role of the gut bacteria in remediation of pollutants was also studied. The analysis of clones covering about 90% of the 16S rRNA clone library indicated that the majority of the taxa in the library resemble GenBank entries of aromatic- hydrocarbon pollutant degraders. Among them Firmicutes and Actinobacteria were dominant. About 84% of the gut isolates were capable of utilizing PAHs as sole carbon sources while 20% of isolates were found to produce biosurfactants. Production of surfactant along with capability to utilize PAH and other pollutants indicate the role of the gut community in alleviating the pollution stress. The results also show the potential source of microorganisms with industrial and environmental application.展开更多
Changes in protein quality during ice storage affects the muscle structure,the textural quality,functional properties and the eating quality.Dynamic viscoelastic behaviour and gelling properties ofmeat proteinsin rela...Changes in protein quality during ice storage affects the muscle structure,the textural quality,functional properties and the eating quality.Dynamic viscoelastic behaviour and gelling properties ofmeat proteinsin relation to histological changes in white leg shrimp muscles were assessed for 14 days in ice storage.Reduction in Ca2+ATPase activity of fresh myofibrillar protein(MFP),fading of myosin banding pattern and increased gapping in myofibrils were clearly observed with progress of storage.The quality indices of the shrimp muscle were well correlated with histological and functional properties as a function of ice storage.Solubility of fresh MFP was 86.76%which decreased to 77.06%on the 14th day of storage period.Emulsion capacity found to increase during storage period.Gel strength of white leg shrimp meat was low(81±14 g cm)and further,reduced nearly 60%compared to fresh sample at the end of storage.The considerable reductions(from 535.77 kPa to 246.56 kPa)in storage modulus values were evident of diminishing elasticity and gelling ability of the meat due to ice storage.Therefore,this study usherd that the histological deterioration in myofibrils may be used as an indication of diminishing biochemical quality and gelling behaviour of the proteins.展开更多
文摘The occurrence of methicillin-resistant staphylococci was investigated in fresh seafood, seafood products and related samples. Staphylococci were isolated from 13 (68.42%) fresh seafood samples, while 3 (15.78%) samples harbored coagulase-positive S. aureus. Resistance to methicillin was observed in 16 isolates of Staphylococcus spp., 15 of which were coagulase-negative S. aureus (MR-CoNS) and one was a coagulase-positive S. aureus (MRSA). The mecA gene is detected by PCR in 10 MR-CoNS and one MRSA strain. The lmrS gene, which codes for a multidrug efflux pump LmrS, is detected only in coagulase-positive isolates.
文摘Histamine fish poisoning (HFP) is a major illness occurring throughout the world due to the consumption of quality of deteriorated fish containing pre-formed histamine from bacterial activities. In the study reported here, the histamine-producing bacteria were isolated from the muscle, gills and the gut of 19 samples of Indian mackerel (Rastrelliger kanagurta) from Mumbai, India. The isolates from modified Niven’s medium (MNM) were confirmed for their ability to produce histamine by using 4 different pH-indicator media, followed by HPLC analyses. Out of 202 isolates, 63 isolates produced considerable amounts of histamine on at least 3 out of 4 media used in this study. The histamine formers were identified by biochemical tests followed by sequencing of their 16SrDNA gene, which showed that 89% of the isolates belonged to 13 different genera of the family Enterobacteriaceae. The non-enterobacterial histamine-producing bacteria belonged to the genera Staphylococcus, Alkaligenes, Shewanella and Psychrobacter.
文摘Adaptation of microbial communities to anthropogenic stress has often been shown to involve reduction in diversity and in selective enrichment of species capable of survival. The gut bacterial community of pollution-stressed polychaete Neanthes chilkaensis was studied using cultivation dependent and independent approaches. The possible role of the gut bacteria in remediation of pollutants was also studied. The analysis of clones covering about 90% of the 16S rRNA clone library indicated that the majority of the taxa in the library resemble GenBank entries of aromatic- hydrocarbon pollutant degraders. Among them Firmicutes and Actinobacteria were dominant. About 84% of the gut isolates were capable of utilizing PAHs as sole carbon sources while 20% of isolates were found to produce biosurfactants. Production of surfactant along with capability to utilize PAH and other pollutants indicate the role of the gut community in alleviating the pollution stress. The results also show the potential source of microorganisms with industrial and environmental application.
文摘Changes in protein quality during ice storage affects the muscle structure,the textural quality,functional properties and the eating quality.Dynamic viscoelastic behaviour and gelling properties ofmeat proteinsin relation to histological changes in white leg shrimp muscles were assessed for 14 days in ice storage.Reduction in Ca2+ATPase activity of fresh myofibrillar protein(MFP),fading of myosin banding pattern and increased gapping in myofibrils were clearly observed with progress of storage.The quality indices of the shrimp muscle were well correlated with histological and functional properties as a function of ice storage.Solubility of fresh MFP was 86.76%which decreased to 77.06%on the 14th day of storage period.Emulsion capacity found to increase during storage period.Gel strength of white leg shrimp meat was low(81±14 g cm)and further,reduced nearly 60%compared to fresh sample at the end of storage.The considerable reductions(from 535.77 kPa to 246.56 kPa)in storage modulus values were evident of diminishing elasticity and gelling ability of the meat due to ice storage.Therefore,this study usherd that the histological deterioration in myofibrils may be used as an indication of diminishing biochemical quality and gelling behaviour of the proteins.
