中文摘要：

采用含胞内脂肪酶的微生物细胞催化油脂原料生产生物柴油是目前生物柴油生产领域的一个新的研究方向。探讨了以聚氨酯泡沫颗粒作为载体固定化R.oryzae细胞对细胞生长与产胞内脂肪酶的影响,并对固定化R.oryzae发酵条件进行了优化,特别对氮源的选用进行了研究。结果表明,选用廉价的豆粉作为有机氮源培养R.oryzae细胞效果较好,与以蛋白胨作为培养基氮源相比,单位培养基所得菌体的总酶活提高至1.55倍,同时,氮源利用率大大提高。进一步考察了有机氮源与无机氮源复合培养R.oryzae细胞的情况,发现豆粉与（NH4）2HPO4复合效果较好。利用正交设计对培养基中各种无机盐成分进行了优化。优化结果为全脂豆粉2%,大豆油3%,MgSO40.035%,K2HPO40.12%,（NH4）2HPO40.10%,上述培养条件下,单位培养基培养菌体胞内脂肪酶活可达6054.2U·L-1培养基。以该条件下培养菌体催化大豆油生产生物柴油,在叔丁醇体系下,反应24h生物柴油得率可达68.5%。

英文摘要：

Utilizing whole cell bioeatalyst instead of free or immobilized enzyme for biodiesel production through enzymatic way has drown more and more attention nowadays, since it is a potential way to reduce catalyst cost. In order to enhance the whole cell stability for repeated uses, Rhizopus oryzae （R. oryzae） IFO4697 whole cell was immobilized within reticulated polyurethane foam particles. The effects of the immobilization on intracellular lipase production and cell growth were studied. Through cell immobilization, the dry biomass of the cell is nearly doubled （from 7 to 14 g.L^-1 culture medium） and the whole cell stability during repeated uses is greatly improved. The fermentation conditions were further optimized to reduce the whole cell production cost, especially for the cost of nitrogen resource. Soybean powder was found to be a suitable organic nitrogen source because of using it the intracellular lipase activity of the whole cell can be significantly improved, which is nearly 1.55 fold of that when peptone is used as nitrogen source. （NH4）2HPO4 was found to be the best inorganic nitrogen source coupling to soybean powder, and the optimum culture medium found consists of 2% soybean powder, 0.035% MgSO4, 0.12% K2HPO4, 0.10% （NH4）2HPO4, 3% soybean oil. Under the using of culture medium with optimum constitution, the total intracellular lipase activity can reach 6054.2 U.（L culture medium）^-1. R. oryzae IFO4697 whole cell produced under above fermentation conditions was used for biodiesel production in tert-butanol system and after reaction for 24 h, the biodiesel yield reaches approximately 68.5%. Therefore the R oryzae was proved to be an effective whole cell catalyst for biodiesel production.