Stability evaluation of lyophilized probiotic bacteria

Abstract

The unregulated use of antibiotics has emerged as a major driving force of antibiotic resistance and public health hazard, particularly in developing countries. This necessitates to find out a solution that benefits humans and animals. Probiotics are one such alternative; they are simply known as beneficial bacteria that exert health benefits to living beings. Probiotic microorganisms are crucial for the biotechnology and food industries. They are frequently employed as starters for the production of probiotic goods, food (such as yogurt, cheese and fermented meats), and food as well as for green chemistry uses. Bacteria can be conveniently preserved using lyophilization. It permits long-term storage and inexpensive distribution at suprazero temperatures while limiting viability and functionality losses by lowering water activity to values below 0.2. This study aimed to determine the efficacy of lyophilized probiotic after lyophilization. All the lyophilized isolates were found to be Gram positive and showed no catalase activity. The isolates fermented the sugars viz. D-glucose, Lactose, and Sucrose. Lyophilized bacteria showed tolerance against 2% and 4% NaCl concentrations. The bacteria also showed tolerance against 0.3% bile salt and pH 3. The isolates were able to inhibit the growth of enteric pathogens viz. Salmonella typhi, Escherichia coli, and Vibrio cholera and resistant to commercially available antibiotics viz. gentamicin, and tetracycline. It is possible to conclude that lyophilization does not affects the efficacy of probiotic bacteria. The study's findings could open up new avenues for the application of probiotic-based feeds and foods as an alternative to antibiotic among stakeholders.