Russell J B, Van Soest P J
Appl Environ Microbiol. 1984 Jan;47(1):155-9. doi: 10.1128/aem.47.1.155-159.1984.
Mixed rumen bacteria from cows fed either timothy hay or a 60% concentrate were incubated with 7.5 mM citrate, trans-aconitate, malate, malonate, quinate, and shikimate. Citrate, trans-aconitate, and malate were fermented at faster rates than malonate, quinate, and shikimate. Acetate was the primary fermentation product for all six acids. Quinate and shikimate fermentations gave rist to butyrate, whereas malate and malonate produced significant amounts of propionic acid. High-pressure liquid chromatography of fermentation products from trans-aconitate incubations revealed a compound that was subsequently identified as tricarballylate. As much as 40% of the trans-aconitate acid was converted to tricarballylate, and tricarballylate was fermented slowly. The slow rate of tricarballylate metabolism by mixed rumen bacteria and its potential as a magnesium chelator suggest that tricarballylate formation could be an important factor in the hypomagnesemia that leads to grass tetany.
将来自喂食梯牧草或60%精饲料的奶牛的混合瘤胃细菌与7.5 mM柠檬酸盐、反乌头酸盐、苹果酸盐、丙二酸盐、奎尼酸盐和莽草酸一起培养。柠檬酸盐、反乌头酸盐和苹果酸盐的发酵速度比丙二酸盐、奎尼酸盐和莽草酸快。乙酸盐是所有六种酸的主要发酵产物。奎尼酸盐和莽草酸发酵产生丁酸盐，而苹果酸盐和丙二酸盐产生大量丙酸。对反乌头酸盐培养物的发酵产物进行高压液相色谱分析，发现一种化合物，随后鉴定为三羧甲基丙烷。高达40%的反乌头酸盐被转化为三羧甲基丙烷，且三羧甲基丙烷发酵缓慢。混合瘤胃细菌对三羧甲基丙烷的代谢速度较慢及其作为镁螯合剂的潜力表明，三羧甲基丙烷的形成可能是导致低镁血症进而引发青草搐搦的一个重要因素。
