Abstract :
Halophilic microorganisms are important in biotechnological application processes, such as commercial production of polymers, enzymes, etc. Fermented foods such as Citron, Chilli, Mango, Emperor, Anchovies and Mackerel contain considerable amount of salt. Salt tolerant microorganisms were isolated using nutrient agar containing 5% NaCl and the plates
were incubated at 37°C for 24 hours from these samples. A total of 24 isolates were obtained from fermented food samples. Predominant gram positive isolates with distinct pigmentation pattern were obtained in this study. The interesting result of the study is the isolation of microorganisms which are able to grow at salt concentration of 10-15%. All the 13 isolates from fermented foods exhibited γ hemolysis which proved to be safe for consumption. The isolates from fermented food indicated amylase production in starch agar. Antimicrobial activity revealed that the isolates inhibited only 2 test pathogenic bacteria out of 5 pathogens tested however at different inhibition levels. The isolates from fermented foods showed the most antimicrobial potency to Bacillus cereus and Pseudomonas aeruginosa thus indicating antagonistic capacity. Most of the selected isolates were found to be susceptible to most of the antibiotics used. Only 4 isolates were resistant to Kanamycin and 2 were resistant to Vancomycin. The results suggested that microorganisms isolated from fermented foods have potential functional properties.
Keyword :
Salt tolerant bacteria, fermented foods, functional properties