Megasphaera elsdenii has been correlated with gas production by human faecal microbiota during fermentation. The objective of this study was to determine the role of M. elsdenii in gas production by the microbiome. Kidney beans and sweet potatoes were subjected to in vitro digestion and dialysis followed by fermentation with ten faecal microbiomes: three with detectable M. elsdenii (Me_D) and seven with no detectable M. elsdenii (Me_ND). Me_D microbiomes produced more gas than the Me_ND microbiomes (p < 0.001). Me_D microbiomes produced more gas during fermentation of sweet potatoes than kidney beans (p < 0.001), while the opposite was true for the Me_ND microbiomes (p < 0.001). Among amplicon sequence variants that were associated with gas production, M. elsdenii had the strongest association (p < 0.001). Me_D microbiomes consumed more acetate and produced more butyrate than Me_ND microbiomes (p < 0.001). Gas production by M. elsdenii was confirmed by fermentation of sweet potatoes and acetate with human and rumen M. elsdenii isolates. The human isolate produced gas on sweet potatoes and acetate. This study suggests that M. elsdenii may be involved in gas production during the fermentation of flatulogenic foods through utilisation of undigestible substrates or cross-feeding on acetate.

Stachyose, raffinose and related flatulence-producing oligosaccharides (α-galactosyl derivatives of sucrose) are associated with desiccation tolerance and storability of seed germplasm. Orthodox seeds of species with a sucrose-to-oligosaccharide ratio of <1.0 have storability half-viability periods >10 years while those >1.0 have a storability half-viability period <10 years. Seeds vary in their composition of oligosaccharides and some accumulate α-galactosyl derivatives of cyclitols. Known and proposed pathways for biosynthesis of soluble oligosaccharides, cyclitols and galactosyl derivatives of cyclitols are presented. Axes, cotyledons, embryos or seeds of 19 species in 7 families (all orthodox seeds) were analysed for sucrose, galactosyl derivatives of sucrose, cyclitols and galactosyl derivatives of cyclitols by high resolution gas chromatography. Sucrose and myo-inositol are universally present and galactinol is present in seeds accumulating stachyose series oligosaccharides. Seeds of some species of Leguminosae accumulate mostly stachyose series oligosaccharides, whereas seeds of other species accumulate varying levels of galactosyl derivatives of cyclitols in addition. Castor bean (Euphorbiaceae) seeds accumulate galactinol and buckwheat (Polygonaceae) embryos accumulate galacto-chiro-inositol instead of the stachyose series oligosaccharides. The mass ratio of sucrose:non-sucrose is related to storability and is applicable to seeds accumulating cyclitol derivatives. Galactinol and galacto-chiro-inositol are proposed to function in the same role as raffinose and stachyose in facilitating desiccation tolerance and storability.

The effect of a daily intake of 14g inulin added to a low-fat spread on fasting blood lipids and gastrointestinal symptoms was investigated in sixty-four young healthy women in a randomized double-blind crossover study involving two periods of 4 weeks. The test spread with and without inulin replaced habitual spread during the test periods. No significant differences between the test periods in plasma total cholesterol, HDL-cholesterol, LDL-cholesterol and triacylglycerol concentrations were observed. Gastrointestinal symptoms assessed with questionnaires showed that in the inulin period there was a significantly (P<0·05) higher degree of discomfort from flatulence and other gastrointestinal symptoms than in the control period. In general, there was no indication of intestinal adaptation to this level of intake of inulin.