Science Alert
Current Research in Bacteriology
  Year: 2011 | Volume: 4 | Issue: 1 | Page No.: 16-22
DOI: 10.3923/crb.2011.16.22
Isolation and Identification of Lactic Acid Bacteria Isolated from Traditional Drinking Yoghurt in Khartoum State, Sudan
Asmahan Azhari Ali

The present study was conducted to evaluate the technological characteristics of lactic acid bacteria used as lactic acid starter in the manufacturing of fermented dairy products and which are suitable to local conditions. Morphological, cultural, physiological and biochemical characteristics were employed to identify Lactic Acid Bacteria (LAB), isolated from drinking yoghurt in different areas in Khartoum state, Sudan. The purification of isolates was done by transferring Gram +ve rods and cocci shaped bacteria to the plates of selective media MRS and M-17, respectively. These isolates were further sub cultured until pure isolates were obtained. From 18 drinking yoghurt samples a total of 303 LAB positives were determined, in which 47 (17.38%) and 256 (82.62%) were identified as lactic acid cocci and lactic acid bacilli, respectively. Additionally, our biochemical tests showed the occurrence of 22 (44.44%) Lactococcus lactis subsp. cremoris and 25 (55.56%) Leuconostoc mesenteroides subsp. cremoris among lactic acid cocci. While, in the case of lactic acid bacilli, Lactobacillus helveticus 35 (15.3%); Lactobacillus plantarum 74 (22.3%); Lactobacillus brevis 17 (21%); Lactobacillus casei subsp. casei 36 (15.5%) and Lactobacillus delbrueckii subsp. bulgaricus 94 (25.9%) was found. Among lactic acid cocci and bacilli, Leuconostoc mesenteroides subsp. cremoris and Lactobacillus delbrueckii subsp. bulgaricus were found to be the more dominant species, respectively. The current study constitutes the first step in the designing process of LAB starter cultures, in order to protect the typical organoleptic characteristics of traditional drinking yoghurt. However, in the future we can consider genetical characterization and selection of the most desirable strains and assess their potential as starter cultures for commercial use.
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08 September, 2019
kokila M:
very nice paper

What color is the sky?