Rhizopus delemar菌固态发酵生物量测定及其脂肪酶合成特征

研究了Rhizopus delemar菌固态发酵曲中麦角固醇的提取及其高效液相色谱（HPLC）测定方法。结果表明，固态曲中麦角固醇分离提取以1：25（w/v)的丙酮回流浸提2.0h为最佳，HPLC测定麦角固醇的条件为：HypersilC-8柱。甲醇/水（85/15，v/v)为流动相，流速为1.0mL/min，紫外检测波长为282nm。柱温为30℃。依据HPLC的分析测定，确定了麦角固醇与菌丝体间的定量关系，并以此为基础。测定了Rhizopus delemar菌固态发酵过程中的生物量变化。得到了生长曲线，发现当发酵培养至60h时固态曲中的生物量达到最大值为0.18g菌丝体/g干曲，而该菌所合成的脂肪酶的活力在48h达到最大值。

Biomass estimation of Rhizopus delemar solid fermentation and its characteristics of lipase syntheses

The biomass of Rhizopus delemar in solid fermentation was estimated by the HPLC determination of ergosterol. The relationship between fungus mycelium and the ergosterol content was studied. The optimum conditions for extracting ergosterol from mycelium of solid culture were established. The HPLC determination was carried out in a Hypersil C- 8 column, with a mobile phase of methanol/water (85/15 ,v/v) and the UV detection at 282nm. The biomass in the culture reached the maximum of 0.18g mycelium/g dry medium after 60h cultivation, while the lipase activity reached the highest of 75IU/g dry medium after 48h cultivation.