Ashes J R, Gulati S K, Cook L J, Mills S C, Scott T W
J Lipid Res. 1978 Feb;19(2):244-9.
Cholesterol was hydrogenated by anaerobic incubation with sheep rumen fluid for periods up to 20 hr. The principal product of cholesterol hydrogenation was identified as coprostanol. Cholesterol could be protected against in vitro ruminal hydrogenation by encapsulation in a matrix of formaldehyde-treated casein. Formaldehyde-treated casein-cholesterol preparations were also shown to be protected against hydrogenation in vivo and, when supplements containing 1 g per day of protected or unprotected cholesterol were fed to sheep over a period of 8-9 weeks, there were marked differences in the plasma cholesterol response. The plasma cholesterol of the sheep fed protected cholesterol increased by at least 60%. The plasma cholesterol of the sheep fed unprotected cholesterol also tended to increase during the first 5 weeks of supplementation but thereafter declined to almost control levels at 8 weeks.
胆固醇与羊瘤胃液进行厌氧培养长达20小时进行氢化。胆固醇氢化的主要产物被鉴定为粪甾烷醇。通过包封在经甲醛处理的酪蛋白基质中，胆固醇可免受体外瘤胃氢化作用。经甲醛处理的酪蛋白 - 胆固醇制剂在体内也被证明可免受氢化作用，并且当向绵羊喂食含每天1克受保护或未受保护胆固醇的补充剂，持续8 - 9周时，血浆胆固醇反应存在显著差异。喂食受保护胆固醇的绵羊血浆胆固醇至少增加了60%。喂食未受保护胆固醇的绵羊血浆胆固醇在补充的前5周也趋于增加，但此后在8周时降至几乎与对照水平相同。
