Abstract

Aureobasidium pullulans LB83 was evaluated for cellulase production under submerged fermentation conditions. Different process variables such as carbon sources (corn cob, sugarcane bagasse, and sugarcane straw), synthetic (urea, ammonium sulfate, and peptone), and non-synthetic (soybean meal, rice, and corn meal) nitrogen sources and inoculum size were evaluated by one parameter at-a-time strategy. Aureobasidium pullulans LB83 showed maximum cellulase activity (FPase, 2.27 U/mL; CMCase, 7.42 U/mL) on sugarcane bagasse. Among the nitrogen sources, soybean meal as a non-synthetic nitrogen sources showed a maximum cellulase activity (FPase 2.45 U/mL; CMCase, 6.86 U/mL) after 60 hr. The inoculum size of 1.6 × 10⁶ CFU/mL had the maximum FPase and CMCase activities of 3.14 and 8.74 U/mL, respectively. For the enzymatic hydrolysis, both the commercial cellulase (10 FPU/g of Cellic CTec 2 (#A) and 10 FPU/g of crude enzyme extract (CEE) (#B), and varying ratio of CTec 2 and CEE in combination #C (5 FPU/g of CTec 2 + 5 FPU/g CEE), combination #D (2.5 FPU/g of CTec 2 + 7.5 FPU/g CEE), and combination #E (7.5 FPU/g of CTec 2 + 2.5 FPU/g CEE) were assessed for enzymatic hydrolysis of delignified sugarcane bagasse. Enzyme combination #C showed maximum hydrolysis yield of 92.40%. The study shows the hydrolytic potential of cellulolytic enzymes from A. pullulans LB83 for lignocellulosic sugars production from delignified sugarcane bagasse.

 抽象的

对出芽短梗霉LB83 在深层发酵条件下的纤维素酶生产进行了评估。不同的过程变量，例如碳源（玉米芯、甘蔗渣和甘蔗秸秆）、合成（尿素、硫酸铵和蛋白胨）和非合成（豆粕、大米和玉米粉）氮源和接种量一次通过一个参数进行评估。出芽短梗霉LB83 对甘蔗渣表现出最大的纤维素酶活性（FPase，2.27 U/mL；CMCase，7.42 U/mL）。在氮源中，豆粕作为非合成氮源在60小时后表现出最大纤维素酶活性（FPase 2.45 U/mL；CMCase，6.86 U/mL）。 1.6 × 10 ⁶ CFU/mL 的接种量具有最大 FPase 和 CMCase 活性，分别为 3.14 和 8.74 U/mL。对于酶水解，使用商业纤维素酶（10 FPU/g Cellic CTec 2 (#A) 和 10 FPU/g 粗酶提取物 (CEE) (#B)，以及不同比例的 CTec 2 和 CEE 组合# C（5 FPU/g CTec 2 + 5 FPU/g CEE）、组合 #D（2.5 FPU/g CTec 2 + 7.5 FPU/g CEE）和组合 #E（7.5 FPU/g CTec 2 + 2.5） FPU/g CEE) 对脱木质素甘蔗渣的酶水解进行了评估，酶组合 #C 的最大水解产率为 92.40%。该研究表明出芽短梗霉LB83 的纤维素分解酶对于从脱木质素甘蔗渣生产木质纤维素糖的水解潜力。