Effect of inulin and fructooligosaccharide supplementation on the growth and survival of Lactobacillus casei in model sugar systems

Abstract

Inulin and fructooligosaccharides (FOS) are widely used prebiotics. In this study, model sugar systems such as glucose, fructose, lactose, and sucrose (2%, 3%, and 4%) were used to investigate the effect of inulin or FOS (0.5%, 1%, 2%, 3%, and 4%) supplementation on the growth and survival of Lactobacillus casei. The highest growth-promoting effect was observed with 2% lactose with 4% inulin or 4% FOS supplementation. Based on the highest percentage increase in growth index (GI) of L. casei, the most suitable sugar for inulin and FOS supplementation was lactose, followed by fructose and glucose. In growth assay, based on the percentage increase in GI, FOS (36.8%) was better than inulin (20.1%) for supplementation in the lactose system. In the glucose system, based on the percentage increase in GI, inulin (7.3%) was better than FOS (6.5%) for supplementation. Likewise, inulin (14.6%) was better than FOS (11.1%) for supplementation in fructose system. Practical applications Probiotics and prebiotics are popular functional ingredients that provides health benefits to the consumers. These two ingredients can be administered individually or together. Experimental results indicated that when prebiotics at different concentrations are supplemented with a probiotic, L. casei in various sugar systems, growth-promoting effect, partial inhibition or no effect on the growth and survival of the probiotic is found. These results serve as a guide for the application of prebiotic supplementation with L. casei in the food industry.