1. IN VITRO EVALUATION OF PROBIOTIC ATTRIBUTES OF LACTOBACILLUS SPP ISOLATED FROM DIFFERENT SOURCES
Monica Puniya1, Nikhil Kumar, Anita Kumari Garsa, Taufeeq Ahmed, Ravinder Kumar Malik and Anil Kumar Puniya
Dairy Microbiology Division, National Dairy Research Institute, Karnal , Haryana.
Introduction
Genus specific PCR
Cell Surface Hydrophobicity
“Probiotics are living microorganisms which upon ingestion in sufficient numbers, exert health benefits beyond basic nutrition.” The real concept of using beneficial microorganisms for improved human health is an area of increasing interest for scientific community. The useful effects of probiotics are results of favorable changes in the intestinal health and immune system. The present study was aimed at studying some of the probiotic attributes of lactobacilli isolates for their possible use in controlling the lifestyle related diseases such as obesity.
Cell surface hydrophobicity
Antibiotic susceptibility
Antibiotics C3
C11 9K
12K
17K
Amikacin30(AK) R
Amoxillin30(AM) S I
Ampicillin10(A)
Ciprofloxacin10
(CF)
Cefuroxime (CU)
Cephalokhin(CH)
Chloramphenicol (C)
Clindamycin(CD)
Erythromycin(E)
Novobiocin(NV)
Kanamycin30(K)
Oxytetracylin(O)
Primer Sequence: LbLMA 1(5’CTC AAA ACT AAA CAA AGT TTC 3’) and R16-1 (5’CTT GTA CAC ACC GCC CGT CA3’)
Methods
Acid & Bile tolerance
Isolation(different dairy and non-dairy sources) & confirmation of Lactobacillus strains using PCR, catalase test and microbiological examination
Screening of Lactobacilli isolates for their survival at different pH (2, 2.5, 6.5) and bile concentrations (0.5%, 1%, 1.5%, 2%) at 0, 1, 2 & 3hrs resp.
Acid Tolerance of C3 and C11
Screening of isolates for bile salt hydrolase (BSH) activity
Susceptible≥20mm
Intermediate≤15-19mm
Resistant ≤ 4mm
Evaluation of cell surface hydrophobicity , antibiotic susceptibility and anti-bacterial activity
Results
Bile Tolerance of C3 and C11
Antibiotic Susceptibility
Bile salt hydrolase (BSH) assay
Conclusions
Out of one hundred Lactobacillus isolates, fifteen were exposed for different probiotic attributes & five isolates were found to have good in vitro tolerance and, therefore, can be exploited for their application in functional dairy foods. Overall, these strains may possibly be the probiotics that can be further validated through in vivo studies to elucidate their potential health benefits.
Microscopical Examination
Gram Staining
References
Antibacterial Spectrum of Activity
FAO/WHO 2002.Guidelines for the evaluation of probiotics in food. Ontario, Canada, USA: Food and Agricultural Organisation.
Performance Standards for Antimicrobial Disk Susceptibility tests Clinical and Laboratory Standards Institute (CLSI):27(1).
ICMR-DBT 2011.Guidelines for evaluation of probiotics in food.New Delhi, India: Indian Council of Medical Research.
BSH activity
Indicator strain C3
C11 9K
12K
17K Lp
P.acedila-ctici Lb 42 ++
+++
Bile Salts C3
C11 9K
12K
17K Lr
Sodium deoxycholate (SD)
+++
Sodium taurocholate (ST) +
Sodium tauroglycocholate (STG) ++
Acknowledgements
We gratefully acknowledge DBT, Biocare Women Scientist scheme for funds & Director, NDRI for providing necessary infrastructure & facilities.
Antibacterial Spectrum
Diameter of zone of inhibition(mm)10-20=+++,
5-10 =++, <5=+
++: moderate precipitation; +: slight -precipitation; +++: intense precipitation