Effect of the gynosaponin on methane production and microbe numbers in a fungus-methanogen co-culture

Abstract

This study investigated the effect of saponins gypenoside (gynosaponins) on methane production and microbe numbers in a co-culture of a fungus, Piromyces sp. F1, and a methanogen, Methanobrevibacter sp.. Two co-culture systems were used: with methanogen (co-culture I) and without methanogen (co-culture II; methanogen growth inhibited by chloramphenicol). Each co-culture system was treated with 0, 50, 100 or 200 mg gynosaponins/l culture medium. Gas production, methane concentration and volatile fatty acid concentration (VFA) were measured for each treatment group. The numbers of anaerobic fungi and methanogen were quantified by real time PCR. The results showed that, compared with the control, gynosaponin significantly reduced the gas production, methane concentration, methane to TVFA ratio (total volatile fatty acid), TVFA concentration, number of fungi (except for 50 mg dose of gynosaponin in co-culture I) and number of methanogens. Methane was not detected in co-culture II. The individual VFAs proportion of TVFA were not affected by gynosaponins in either of the co-cultures. The pH was higher in both co-cultures than that of the control (P<0.01). These data suggest that gynosaponins has the potential for being used as feed additive to modulate the ruminal fermentation, inhibit the methanogen growth and reduce methane production.

Caecal infusion of the short‐chain fatty acid propionate affects the microbiota and expression of inflammatory cytokines in the colon in a fistula pig model

“…After overnight at −20°C, the supernatant was centrifuged at 13 400 g for 10 min, then, filtered with a 0.22 μm filter for measurement. The Agilent 7890B Gas Chromatograph was used to determine the concentration of SCFAs according to the method by Wang and colleagues ().…”

Effect of Gynosaponin on Rumen &lt;i&gt;In vitro&lt;/i&gt; Methanogenesis under Different Forage-Concentrate Ratios

“…The addition level of gynosaponin was based on previous researches (Hu et al, 2005; Guo et al, 2008; Wang et al, 2011) and the set of serum bottles without gynosaponin was served as control. Each set had four replicates.…”

“…After the total gas measurement, methane production was determined using capillary column gas chromatograph (GC-14B, Shimadzu, Japan), with details as described by Wang et al (2011). The amount of methane was calculated using standard curves (eight points with triplicate estimations; R 2 coefficients of 0.994).…”

Papaya (Carica papaya) leaf methanolic extract modulates in vitro rumen methanogenesis and rumen biohydrogenation

“…Protozoa represents almost half of the microbial biomass in the rumen. It is expected that reducing protozoa would also reduce methanogen populations because 10 to 20% of methanogens live in association with protozoa, thus decreasing methane production (Wang et al 2011). Interestingly, populations of total methanogens were affected (P < 0.05) by PLE, especially at higher concentrations (HLE).…”