دوره 8، شماره 4 - ( 6-1399 )                   جلد 8 شماره 4 صفحات 200-189 | برگشت به فهرست نسخه ها


XML Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Ghazaei C. Isolation and Characterization of Lactic Acid Bacteria From Milk and Their Effects on the Pathogenic Bacteria. Res Mol Med (RMM) 2020; 8 (4) :189-200
URL: http://rmm.mazums.ac.ir/article-1-374-fa.html
Isolation and Characterization of Lactic Acid Bacteria From Milk and Their Effects on the Pathogenic Bacteria. Research in Molecular Medicine. 1399; 8 (4) :189-200

URL: http://rmm.mazums.ac.ir/article-1-374-fa.html


چکیده:   (2474 مشاهده)
Background: Probiotics are “live microbial cells” that are beneficial for human and animal health. Lactobacilli are such a diverse group of bacteria with similar metabolic and physiological characteristics, and constitute important and beneficial gut microflora. During carbohydrate fermentation, lactobacilli produce lactic acid as an end product in metabolism. Hence, lactobacilli have high significance to be used as probiotics in the food industry, because of their acidifying properties. Also, lactobacilli are considered “safe”, owing to their ubiquitous presence in the food. Many researchers provided evidence for the presence of lactobacilli in milk sources. Thus, the present study aimed to isolate and characterize different lactobacilli strains from milk sources and analyze their “probiotic potential”.
Materials and methods: Forty-one lactobacilli isolates were obtained from raw cow milk. Then, the strains were characterized by morphological identification and biochemical tests. Besides, probiotic potentials were evaluated with the bile tolerance test, antibiotic susceptibility test, and determining suitable pH for the optimal growth of lactobacilli. The lactobacilli isolates were also analyzed for their probiotic characteristics and the release of antimicrobial substances. Their antimicrobial activities against pathogenic strains were assessed by determining the minimum inhibitory concentration, with the help of agar diffusion methods.
Results: From 50 milk samples, 41 lactobacilli isolates were obtained, out of which five lactobacilli strains were identified as Lactobacillus casei, Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus acidophilus, and Lactobacillus lactis. Moreover, 35 isolates showed an inhibitory effect. These strains were able to survive and grow in 0.5% to 2.5% bile salt concentrations. Lactic acid bacteria were susceptible to antibiotics, and 35 isolates obtained from raw milk showed an inhibitory effect against pathogenic bacteria. The observed minimum inhibitory concentration ranged from 50 to 100 µL and varied between the different pathogens.
Conclusion: Out of 41 Lactobacillus isolates obtained from cow milk samples, 35 were identified with probiotic characteristics. Hence, this study highlighted the novel probiotic bacteria and validated the antimicrobial properties of the Lactobacillus spp against pathogenic bacteria.
 
متن کامل [PDF 1197 kb]   (1077 دریافت)    
نوع مطالعه: پژوهشي | موضوع مقاله: ميکروبيولوژي
انتشار: 1399/7/9

ارسال نظر درباره این مقاله : نام کاربری یا پست الکترونیک شما:
CAPTCHA

بازنشر اطلاعات
Creative Commons License این مقاله تحت شرایط Creative Commons Attribution-NonCommercial 4.0 International License قابل بازنشر است.

کلیه حقوق این وب سایت متعلق به Research in Molecular Medicine می باشد.

طراحی و برنامه نویسی : یکتاوب افزار شرق

© 2024 CC BY-NC 4.0 | Research in Molecular Medicine

Designed & Developed by : Yektaweb