Improved yield of α-L-arabinofuranosidase by newly isolated Aspergillus niger ADH-11 and synergistic effect of crude enzyme on saccharification of maize stover

Abstract

Background: In the view of depleting resources and ever-increasing price of crude oil, there is an urge for the development of alternative sources to solve the issue of fuel in the coming years. Lignocellulosic biomass is considered to be the most potential alternative resources for fossil fuel. Bioconversion of cellulosic and hemicellulosic components into fermentable sugars is the key step in producing fuel ethanol from lignocellulose. The enzymatic hydrolysis of lignocellulosic biomass needs a highly balanced composition of cellulases and hemicellulases. Commercial enzymes are usually poor in accessory hemicellulolytic enzymes like α-L-arabinofuranosidase. The addition of such accessory enzymes in combination with cellulase or hemicellulase plays a vital role in improving the total yield of fuel ethanol by enhancing the saccharification yield. Results: The newly isolated fungal strain Aspergillus niger ADH-11 produced a maximum of 22.14 U/g of α-L-arabinofuranosidase under solid-state fermentation using wheat bran as the substrate and modified Mandels-Weber medium at 30°C after 180 h of incubation. The optimization of various fermentation parameters was performed by response surface methodology employing Plackett-Burman design followed by Box-Behnken design. The yield of α-L-arabinofuranosidase was enhanced by 2.34-fold after executing statistical optimization of various fermentative parameters. Crude α-L-arabinofuranosidase was found to be highly stable for 3 h at its optimum temperature (55°C) and pH (4.0). The assessment of the crude enzyme extract in saccharification of alkali-treated maize stover revealed that the supplementation of crude α-L-arabinofuranosidase to commercial cellulase and crude xylanase mixture increased the saccharification yield up to 730 mg/g of maize stover.

Significant enzymatic activities in the residues hydrolysis of the sugar cane harvest

“…According to Patel, et al, 2015 andSilverstein, et al, 2007 [31-32], the composition of enzymes is a crucial factor that affects the successful application of enzymes in biorefineries. Effective bioconversion of lignocellulosic material into fermentable sugars requires a balanced composition of cellulolytic and hemicellulolytic enzymes.…”

Canola meal as a novel substrate for β-glucosidase production by Trichoderma viride: application of the crude extract to biomass saccharification

“…The presence of main chain depolymerizing and debranching hemicellulolytic enzymes in T. viride crude extract may also have contributed to the increased glucose levels. Recently, Patel et al [55] reported that supplementation of crude a-L-arabinofuranosidase with commercial cellulase and crude xylanase during saccharification of maize stover increased the glucose yield by up to 176.8 %. Delabona et al [56] made a similar observation; their studies on sugarcane bagasse strongly suggested that supplementation of commercial cellulase with xylanolytic enzymes resulted in greater sugar release.…”

Perbandingan Metode Uji Gula Pereduksi Dalam Penentuan Aktivitas ?-L-Arabinofuranosidase Dengan Substrat Janur Kelapa (Cocos Nucifera)

“…Hemiselulase diaplikasikan dalam proses sakarifikasi, peningkatan kualitas kertas, industri obat dan degradasi limbah pertanian (Liao et al, 2014;Patel et al, 2015). Enzim α-L-arabinofuranosidase (EC 3.2.1.55) merupakan salah satu hemiselulase yang berperan dalam biokonversi lignoselulosa menjadi oligosakarida dan monosakaridanya.…”

“…Enzim ini merupakan ekso enzim yang dapat memotong ikatan pada ujung non-pereduksi α-L-1,2-, α-L-1,3-dan α-L-1,5-arabinofuranosidik serta berperan pada hidrolisis substrat oligosakarida dan polisakarida. Penelitian tentang α-L-arabinofuranosidase ini diperlukan karena berperan penting sebagai enzim kunci pendegradasi xilan dalam hemiselulosa, sehingga banyak diteliti dalam beberapa tahun belakangan (Patel, et al, 2015).…”