Toxicity and Metabolism of the Conjugates of 3-Nitropropanol and 3-Nitropropionic Acid in Forages Poisonous to Livestock

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• 作者：Robin C. Anderson ; Walter Majak ; Mark A. Rassmussen ; Todd R. Callaway ; Ross C. Beier ; David J. Nisbet ; and Milton J. Allison
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2005
• 出版时间：March 23, 2005
• 年：2005
• 卷：53
• 期：6
• 页码：2344 - 2350
• 全文大小：834K
• 年卷期：v.53,no.6(March 23, 2005)
• ISSN：1520-5118

文摘

Glycosides of 3-nitro-1-propanol (nitropropanol) and glucose esters of 3-nitro-1-propanoic acid(nitropropionic acid) occur in many forages distributed throughout the world. Systemically, nitropropionicacid irreversibly inactivates succinate dehydrogenase, thereby blocking ATP formation. Nitropropanolis not toxic per se in mammals but is converted to nitropropionic acid by hepatic alcoholdehydrogenase. Nitrotoxins can be metabolized by rumen microbes, which may provide a mechanismfor detoxification. At least 20 different ruminal bacteria are known to metabolize the nitrotoxins, butmost appear to play a minor role in detoxification. Evidence suggests that an obligate anaerobicnitro-respiring bacterium, Denitrobacterium detoxificans, may be particularly important in conferringprotection to animals consuming the nitrotoxins as this bacterium metabolizes the toxins at ratesnear those by mixed ruminal populations. Rates of ruminal nitrotoxin metabolism can be enhancedby modifying the rumen environment through dietary manipulations, which suggests in vivo enrichmentof competent nitrotoxin-metabolizing bacteria such as D. detoxificans.Keywords: Toxic plant; Astragalus; Coronilla; Hippocrepis; Indigofera; Lotus; toxic fungi; Arthrinium;Aspergillus; Penicillium; 3-nitropropanol; 3-nitropropionic acid; rumen metabolism; Denitrobacterium