de Castro Aline Machado, Carvalho Daniele Fernandes, Freire Denise Maria Guimarães, Dos Reis Castilho Leda
Renewable Energy Division, Research and Development Center, PETROBRAS, Avenue Horácio Macedo, 950 Ilha do Fundão, Rio de Janeiro 21941-915, Brazil.
Enzyme Res. 2010 May 23;2010:576872. doi: 10.4061/2010/576872.
Amylases are one of the most important industrial enzymes produced worldwide, with their major application being in ethanol manufacturing. This work investigated the production of amylases by solid-state fermentation of babassu cake, using the filamentous fungus Aspergillus awamori IOC-3914. Lab-scale experiments were carried out to generate input data for simulations of an industrial plant for amylase production. Additionally to the target enzymes, other hydrolases (cellulases, xylanases, and proteases) were also produced, enriching the final product. The most suitable fermentation time was 144 hours, when exoamylase and endoamylase activities of 40.5 and 42.7 U g(-1) were achieved, respectively. A first evaluation showed a large impact of the inoculum propagation medium on production costs. Therefore, five propagation media were compared, and PDA medium presented the best cost-benefit ratio. The credits obtained from sales of fermented cake as a coproduct enabled a significant decrease in the production cost of the enzyme product, down to 10.40 USD kg(-1).
淀粉酶是全球生产的最重要的工业酶之一，其主要应用于乙醇制造。本研究利用丝状真菌泡盛曲霉IOC-3914对巴巴苏饼进行固态发酵来生产淀粉酶。开展了实验室规模的实验，以生成用于淀粉酶生产工业装置模拟的输入数据。除了目标酶之外，还产生了其他水解酶（纤维素酶、木聚糖酶和蛋白酶），从而丰富了最终产品。最合适的发酵时间为144小时，此时外切淀粉酶和内切淀粉酶的活性分别达到40.5和42.7 U g(-1)。初步评估表明接种物增殖培养基对生产成本有很大影响。因此，比较了五种增殖培养基，马铃薯葡萄糖琼脂（PDA）培养基的成本效益比最佳。作为副产品销售发酵饼所获得的收益使得酶产品的生产成本大幅降低，降至10.40美元/千克。
