ISOLATION AND FREEZE DRYING OF CERTAIN PROBIOTIC STRAINS

Abstract

The aim of the present study was to evaluate few probiotics strains available commercially in Lahore city and isolation and identification of strains from these commercial probiotics. The identified and isolated probiotic strains were freeze dried. These strains included Lactobacillus acidophilus, Bifidumbacterium bifidus and Saccharomyces boulradii. Both the commercial and laboratory freeze dried probiotic micro-organisms were subjected to microbial studies. The isolation of the microbes was done by using different types of growth media and identification of microbes was based on fermentation of different carbohydrates, gas production from glucose, growth at various temperature and tolerance to sodium chloride, colony characteristics and staining. The actual microbial count in laboratory of commercial probiotics indicated that there was a discrepancy in the viable count stated on the label of Lactobacillus acidophilus, Bifidumbacterium bifidus i.e., the actual viable count is less than the stated viable count on the label. This laboratory evidence suggest that bacteria cannot survive longer time on shelves which is probably the main reason that probiotics inspite of their in vivo effectiveness have not found a good way in physician prescription pattern. However, such discrepancy was not observed in case of yeast. The microbiological studies suggested that it is feasible to isolate, identify and freeze dry the microbes in the laboratory and pilot plant scale. The microbial count after freeze drying of laboratory prepared probiotics had shown that anaerobic bacteria (Bifidumbacterium bifidus) survived more during the freeze drying as compared to Lactobacillus acidophilus and yeast survive more than the both bacterial strains.