Enhancement of Short Chain Fatty Acid Production from Millet Fibres by Pure Cultures of Probiotic Fermentation

Purpose: To enhance the in vitro synthesis of short chain fatty acids through millet dietary fibre fermentation by human faecal probiotic bacteria. Methods: The effect of millet dietary fibre fermentation on production of short chain fatty acids (SCFA) by four probiotics was studied. Dietary fibre was extracted from two millet varieties viz Pearl millet, Pennisetum glaucum (PM) and Foxtail millet (FxM, Setaria italica), and separated into total dietary fibre (TDF), insoluble dietary fibre (IDF) and soluble dietary fibre (SDF). Four probiotic bacteria (Lactobacillus rhamnosus, Lactobacillus acidophilus, Bifidobacterium longum and Bifidobacterium bifidus) were grown on specific medium containing IDF, SDF and TDF. SCFA production by the probiotics was measured at 0, 6, 24, and 48 h using gas liquid chromatography. Results: SCFA production in the fibre fractions followed the rank order, TDF SDF IDF, irrespective of millet variety, indicating that TDF is the best possible dietary fibre for SCFA production. Lactobacillus and Bifidobacteria spp. digested 60 – 80 and 75 – 85 % of the millet fibre fractions from both millet samples, respectively. The quantity of different SCFAs produced was in the rank order: acetate propionate butyrate. Conclusion: The results from this study suggest that millet dietary fibre has a potential for conversion into new nutraceuticals.