背景:使用真菌生物质进行生物催化是使用酶的昂贵成本的潜在解决方案。具有有效活性的真菌生物质的生产需要优化培养条件。
结果:优化了根霉生物量,用于酯交换和废煎炸油(WFO)的水解。与静态条件相比,在摇动条件下,Storonifer的生长和生物量脂解活性得到了改善,和200rpm是最佳的。作为生物质脂肪酶和酯交换活性诱导剂,橄榄油优于大豆,油菜籽,和废煎炸油。在含有鱼粉作为N源原料的培养基中产生的生物质比玉米浆和尿素具有更高的脂解能力。PlackettBurman对9个因素的筛选结果表明,pH(5-9),鱼粉(0.25-1.7%,w/v),和KH2PO4(0.1-0.9%,w/v)是具有最高主效应估计的显著因素,分别为11.46、10.42、14.90。选择这些因素用于使用中央复合设计(CCD)的响应面方法(RSM)优化。用于增长的CCD模型,生物质脂肪酶活性,和酯交换能力显著。生长和脂质修饰催化活性的最佳条件为pH7.4,鱼粉(2.62%,w/v),和KH2PO4(2.99%,w/v)。
结论:优化的培养条件提高了以脂肪酸甲酯(FAME)浓度为67.65%的长柄根霉生物质的全细胞酯交换能力,最终FAME浓度为85.5%,w/w。
BACKGROUND: Using fungal biomass for biocatalysis is a potential solution for the expensive cost of the use o enzymes. Production of fungal biomass with effective activity requires optimizing the cultivation conditions.
RESULTS: Rhizopus stolonifer biomass was optimized for transesterification and hydrolysis of waste frying oil (WFO). Growth and biomass lipolytic activities of R. stolonifer improved under shaking conditions compared to static conditions, and 200 rpm was optimum. As biomass lipase and transesterification activities inducer, olive oil was superior to soybean, rapeseed, and waste frying oils. Biomass produced in culture media containing fishmeal as an N-source feedstock had higher lipolytic capabilities than corn-steep liquor and urea. Plackett Burman screening of 9 factors showed that pH (5-9), fishmeal (0.25-1.7%, w/v), and KH2PO4 (0.1-0.9%, w/v) were significant factors with the highest main effect estimates 11.46, 10.42, 14.90, respectively. These factors were selected for response surface methodology (RSM) optimization using central composite design (CCD). CCD models for growth, biomass lipase activity, and transesterification capability were significant. The optimum conditions for growth and lipid modification catalytic activities were pH 7.4, fishmeal (2.62%, w/v), and KH2PO4 (2.99%, w/v).
CONCLUSIONS: Optimized culture conditions improved the whole cell transesterification capability of Rhizopus stolonifer biomass in terms of fatty acid methyl ester (FAME) concentration by 67.65% to a final FAME concentration of 85.5%, w/w.