Growth Studies of Probiotic Bacteria on Short Chain Glucomannan, a Potential Prebiotic Substrate.

摘要

This report describes a 3-year study, completed in September 2009 by the Natick Soldier Research, Development and Engineering Center, to investigate the prebiotic potential of glucomannan (GM) oligosaccharides as a novel dietary approach to assist in alleviating gastrointestinal distress in deployed troops. Konjac flour was enzymatically hydrolyzed using cellulase and mannanase. A comparison study was done with cellulase produced GM (GMc) and two commercial prebiotic substrates. All three substrates had similar degree of polymerization (DP) of 2-9. Five probiotic bacteria were evaluated for growth with these substrates, four Bifidobacteria (three B. bifidum strains and a B. longum) and a Lactobacillus reuteri. The growth on the GMc after normalizing for glucose content in the GMc was due to glucose in the hydrolysate, not the GMc.-mannanase produced GM (GM946) resulted in a DP=2-7 and a much lower glucose content than GMc (DP=2-3). An expanded list of Bifidobacteria and Lactobacillus species were evaluated for growth on the GM946 substrate; no growth was evident with the GM946. However, non-traditional probiotic sporeforming bacteria, Bacillus subtilis and Bacillus coagulans, grew very well on GM946. In addition, B. subtilis grown in GM946 secreted an antimicrobial substance not detected in media containing glucose or another commercial prebiotic. It was concluded that low molecular weight GM hydrolysates do not support the growth of Bifidobacteria and Lactobacillus bacteria; however, it will support the growth of non-traditional probiotic sporeforming bacteria and can enhance their probiotic potential.