Department of Chemistry, Wroclaw University of Environmental and Life Sciences, Wrocław, 50-375, Poland.
Sci Rep. 2018 Jul 5;8(1):10157. doi: 10.1038/s41598-018-28412-y.
The study show usefulness of rapeseed cake, rich in fats and proteins byproduct generated after oil production, which may be used as a microbial medium for lipase and protease biosynthesis. Of 26 different filamentous fungi screened by solid-state fermentation, Penicillium camemberti AM83 was found to abundantly produce lipase and protease. Various process parameters were then optimized to maximize lipase and protease secretion, including carbon and nitrogen source, C/N ratio, metal ions, temperature, moisture content, initial pH, and inoculum size. Lipase production increased approximately 11.2-fold in solid-state cultures on rapeseed cake supplemented with lactose and calcium chloride, alkalinized to pH 8, hydrated to 80%, and inoculated with 1.2 × 10 spores/mL. Similarly, protease production increased approximately 8.4-fold in optimized cultures inoculated with 3.2 × 10 spores/mL, and grown on rapeseed cake with lactose and ammonium sulfate at pH 9 and moisture content 60%. The results highlight the potential economic value of solid-state fermentation on rapeseed cake to produce industrial hydrolases.
该研究表明，菜籽油生产过程中产生的富含脂肪和蛋白质的副产品——菜籽饼具有实用性，可作为脂肪酶和蛋白酶生物合成的微生物培养基。通过固态发酵筛选出的 26 种不同丝状真菌中，发现冠突散囊菌 AM83 大量产生脂肪酶和蛋白酶。然后优化了各种工艺参数，以最大限度地提高脂肪酶和蛋白酶的分泌，包括碳源和氮源、C/N 比、金属离子、温度、水分含量、初始 pH 值和接种量。在添加乳糖和氯化钙的菜籽饼固态培养物中，将 pH 值碱化至 8，水合至 80%，并以 1.2×10 spores/mL 的接种量接种，脂肪酶的产量增加了约 11.2 倍。类似地，在优化的培养物中以 3.2×10 spores/mL 的接种量接种，在 pH 值为 9、水分含量为 60%的乳糖和硫酸铵存在下的菜籽饼上生长，蛋白酶的产量增加了约 8.4 倍。这些结果突出了固态发酵菜籽饼生产工业水解酶的潜在经济价值。
