Abstract

The probiotic potential of lima bean flour fermented with Lactobacillus sp. in vitro and in vivo was studied. 3 species of Lactobacillus including Lactobacillus fermentum,Lactobacillus plantarum and Lactobacillus cellebiosus were isolated from traditionally prepared ‘ogi’ made from white and yellow maize (Zea mays) and from red guinea corn (Sorghum bicolor), after which they were screened for their growth and survival in Lima bean flour. Among all the species, L. plantarum showed appreciable growth (9.3 × 10⁶ cfu/ml) after 72 h fermentation at 37°C. On storing the fermented products for 14 days at 24 ± 2°C, no marked change in the viable count of this species was observed. In contrast, the number of other species, that is, L. fermentum and L. cellebiosusreduced. There was marked increase in bacterial counts of all the products after storage at room temperature (24 ± 2°C) for 14 days compared to those stored at refrigeration temperature (4 ± 2°C). The physicochemical analysis of the fermented samples showed increase in total titratable acidity (TTA) and temperature with a gradual reduction in pH. There was an increase in protein content and decrease in carbohydrate, ash and moisture contents in the fermented sample compared with the unfermented sample. Under different pH ranges, L. plantarum also showed appreciable growth and survival at pH 2 to 3. Supplementing the diet of albino rats infected with Escherichia coli with the fermented product increased significantly the number of Lactobacilli, compared to the control and at the same time, the number of E. coli and other feacal enterobacteria decreased significantly. This study revealed that Lima bean flour fermented with L. plantarum could be used as an excellent probiotic food.

Key words: Lactobacillus species, lima beans, fermentation, probiotics and gastrointestinal tolerance.