Degradation of L‐5‐vinyloxazolidine‐2‐thione, a goitrogenic product from rapeseed, by rumen microorganisms

Abstract

The use of rapeseed meal for animal feeding is limited by the presence of antinutritional compounds, such as glucosinolates. An in vitro rumen system was used to test the effect of L-5-vinyloxazolidine-2-thione GEERTMAN ET AL.(VOT), a toxic hydrolysis product from glucosinolates found in rapeseed. The effect of VOT on rumen performance was minimal. The VOT was degraded efficiently (60-70%) in the artificial rumen system, when rapeseed was fed batchwise at 20% (w/w) of the diet. The degradation of VOT is caused by bacteria because the addition of the (oil containing) rapeseed resulted in a disappearance of ciliated protozoa. Experiments with pure VOT resulted in complete degradation both in batch (2 mM) and in continuous culture (4 mM).

The Rumen Microbial Ecosystem

“…Lanzani et al (1974) presented evidence that ruminal microbes degraded the intermediate toxins formed from glucosinolate hydrolysis, although degradative activity appears to be dependent on the degree of adaptation and the type of glucosinolate in the diet (Forss and Barry, 1983). The degradation of L-5-vinyloxazolidine-2-thione by ruminal microbes has been reported (Geertman et at., 1994). The degradation of L-5-vinyloxazolidine-2-thione by ruminal microbes has been reported (Geertman et at., 1994).…”

Effects of different levels of rapeseed cake containing high glucosinolates in steer ration on rumen fermentation, nutrient digestibility and the rumen microbial community

“…Since Peptostreptococcus and Bifidobacterium are two prevalent bacteria in the rumen of heifers (45) , the SCN found in the rumen digesta of the present trial should have been from the microbial hydrolysis of GLS in RSC. ISCN and goitrin can be rapidly hydrolysed by rumen microbes, while SCN was relatively unreactive in an in vitro culture of bovine ruminal fluid (46,47) . This finding could be the reason that SCN was the metabolite of GLS rather than goitrin or ITC found in the rumen fluid in the present trial.…”