乳酸脱氢酶（LDH）是米根霉代谢生产L-乳酸过程的关键酶，研究其在发酵过程中的活力变化，从酶水平分析发酵条件对L-乳酸发酵的影响，对米根霉发酵生产L-乳酸的人工代谢调节、菌种选育具有重要意义。本文研究了摇瓶条件下的米根霉AS3.1208发酵体系中乳酸脱氢酶的活力调控条件及与L-乳酸即时产率的关系，结果表明，发酵体系中L-乳酸产率与LDH 活力在36～40h时最高。葡萄糖作为C源的L-乳酸产率与LDH活力比甘薯淀粉高。与牛肉膏和蛋白胨相比，硫酸铵是米根霉代谢的最佳N源，0.40%的硫酸铵具有较高的乳酸产率与LDH活力。发酵培养基中添加CaCO3与否，对乳酸产率与LDH活力有极大影响。以甘薯淀粉为碳源，在250ml三角瓶中的装液量为100ml，发酵36～40h时的L-乳酸即时产率最大，此时LDH活力也最高。

Tocopherol and fatty acid methyl esters (FAME) were recovered through a process involving acid-catalysed methyl esterification and crystallisation of sterols followed by molecular distillation from rapeseed oil deodoriser distillate (RODD), a by-product of vegetable refining edible oil. The effects of evaporating temperature, feed flow rate and wiper rolling speed on yield of tocopherol were systematically studied by response surface methodology (RSM) based on the separation of fame previously. The first fraction, which was collected at 50℃ at 2.66 Pa, contains mainly hydrocarbons, ketones and aldehydes. The second fraction, which was collected at 100-110℃ at 5.32 Pa, contains mainly FAME and the content of FAME in the second distillate was above 90% by analysis of gas chromatography-mass spectrometry (GC-MS). The fraction collected at 200-230℃C at 2.66 Pa was rich in tocopherol (nearly 35%). The overall recovery of tocopherol and FAME were around 50% and 90%, respectively, of the original content in RODD.