Document Type : Research Paper
Authors
1
Medical Biotechnology Research Center, Department of Biology, Ashkezar Branch, Islamic Azad University, Ashkezar, Yazd, Iran
2
Ph.D food Sciences and Technology , Food and Drug Departeman, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
Abstract
The genus Lactobacillus contains several Gram-positive bacteria that are microaerophilic or facultatively anaerobic. These are the main groups of lactic acid bacteria. Some lactobacilli are used in the production of yogurt, cheese, and other fermented products. The purpose of this study was to isolate, identify, and characterize the technological characteristics of lactic acid isolated from a single-humped camel in the city of Tabas, Iran,by standard technological properties tests. From a total of 12 raw milk samples, 60 isolates were investigated by morphological and Gram studies. Thirty-six isolates of catalase-negative and Gram-positive selected for genus identification were compared using the Bergey Book. All examined isolates were analyzed to determine the carbohydrate fermentation pattern and CO2 production. The results showed that 23 isolates of Lactobacillus (with a 63.88% frequency) were found in five groups, including Lactobacillus gasseri isolates (L1-L7), Lactobacillus gallotix isolates (L8-L13), Lactobacillus xiangfangensis isolates (L14-L16), Lactobacillus salivarius isolates (L17-L21), and Lactobacillus paracasei isolates (L22, L23). Additionally, five Pediococcus isolates, P1-P5 (13.99%), and eight Enterococcus isolates, E1-E8 (2.22%), were obtained. Seven isolates were evaluated for molecular identification using 16S rRNA. Finally, five Lactobacillus, one Pediococcus, and one Enterococcus were identified. These seven isolates were examined by complementary tests including proteolytic, lipolytic and autolytic activities, and antibiotic and acid resistance. Two isolates, K030508 (L. salivarius) and K020704 (L. xiangfangensis), exhibited the highest potential for future commercial use as a starter culture.
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