Biological Control of Pests Research Unit, Agricultural Research Service, US Department of Agriculture, P.O. Box 67, Stoneville, MS 38776, USA.
Toxicon. 2013 Nov;74:68-75. doi: 10.1016/j.toxicon.2013.07.026. Epub 2013 Aug 7.
Trichothecenes, a major class of mycotoxins produced by Fusarium, Myrothecium, and Stachybotrys species, are toxic to both plants and mammals. Simple trichothecenes, including type A (e.g., T-2 toxin) and type B (e.g., deoxynivalenol), are generally less toxic than macrocyclic trichothecenes. We sought to determine if simple trichothecenes are a potential source of candidates for development as bioherbicides, which require high phytotoxicity and low mammalian toxicity. We examined 28 simple trichothecenes in vitro for phytotoxicity using a small aquatic plant, Lemna pausicostata, and for mammalian toxicity using four cultured mammalian cell lines. Several structure-activity relationships were identified, including the following two, which may be relevant to bioherbicide development: peracetylation of type B trichothecenes and de-epoxidation of type A trichothecenes both substantially reduced mammalian toxicity with little effect on phytotoxicity. It was concluded that simple trichothecenes possessing strong phytotoxicity and minimal mammalian toxicity in vitro can be identified.
单端孢霉烯族化合物是由镰刀菌属、木霉属和链格孢属产生的一类主要真菌毒素，对植物和哺乳动物都有毒性。简单的单端孢霉烯族化合物，包括类型 A（例如 T-2 毒素）和类型 B（例如脱氧雪腐镰刀菌烯醇），通常毒性低于大环单端孢霉烯族化合物。我们试图确定简单的单端孢霉烯族化合物是否是作为生物除草剂开发的潜在候选物，生物除草剂需要高植物毒性和低哺乳动物毒性。我们使用小型水生植物浮萍（Lemna pausicostata）在体外研究了 28 种简单的单端孢霉烯族化合物的植物毒性，并使用四种培养的哺乳动物细胞系研究了它们的哺乳动物毒性。确定了几个结构-活性关系，包括以下两个，它们可能与生物除草剂的开发有关：B 型单端孢霉烯族化合物的乙酰化和 A 型单端孢霉烯族化合物的脱环氧作用都大大降低了哺乳动物的毒性，而对植物毒性几乎没有影响。结论是，可以识别具有强植物毒性和最小哺乳动物毒性的体外单端孢霉烯族化合物。
