Co-Cultivation of Penicillium sp. AKB-24 and Aspergillus nidulans AKB-25 as a Cost-Effective Method to Produce Cellulases for the Hydrolysis of Pearl Millet Stover

Abstract

Hydrolysis of cellulose and hemicelluloses into fermentable sugars is the primary step for the production of fuels and chemicals from lignocellulosic biomass, and is often hindered by the high cost of cellulolytic and hemicellulolytic enzymes. In the present study co-and monocultures of Penicillium sp. AKB-24 and Aspergillus nidulans AKB-25 were used under a variety of fermentation conditions to optimize enzyme production. Wheat bran was found to be the optimal carbon source yielding maximum enzyme production under solid-state fermentation conditions due to its higher water retention value (175%) and minimum C/N ratio (22.7). Penicillium sp. AKB-24 produced maximum endoglucanase (134 IU/gds), FPase (3 FPU/gds), β-glucosidase (6 IU/gds) and xylanase (3592 IU/gds) activities when incubated for 7 days at 30˝C and pH 7 with a moisture content of 77.5%, and 1.2% yeast extract and 0.1 (w/v) sodium dodecyl sulphate supplement. Co-culturing of Penicillium sp. AKB-24 and Aspergillus nidulans AKB-25 enhanced endoglucanase, FPase, and exoglucanase activities by 34%, 18%, and 11% respectively compared to Aspergillus nidulans AKB-25 alone under optimum conditions. Enzymes produced by co-cultivation released equal amounts of reducing sugars at an enzyme dose of 15 FPU/g and reaction time 72 h, but the required quantity of enzyme was 14% less compared to enzyme released from Aspergillus nidulans AKB-25 mono-culture. In conclusion, co-cultivation of Penicillium sp. AKB-24 and Aspergillus nidulans AKB-25 to produce enzymes for the hydrolysis of pearl millet stover is more cost-effective than cultivation with Aspergillus nidulans AKB-25 alone.

Exploitation of Parthenium hysterophorous biomass as low-cost substrate for cellulase and xylanase production under solid-state fermentation using Talaromyces stipitatus MTCC 12687

“…Crude enzyme was centrifuged at 8000 rpm for 15 min to obtained clear supernatant. The crude enzyme was analysed to measure endoglucanase, b-glucosidase, FPase and xylanase activities (Kumar et al, 2016).…”

“…Moreover, wheat bran is a good source of different nutrients such as proteins, hemicelluloses, iron, zinc, and manganese for microorganisms. It consists of starch (13.8%e24.9%), protein (13.2%e18.4%), cellulose (11.0%), hemicellulose (10.9%e26%), fats (3.5%e3.9%), phenolic acids (1.1%), and ash (3.4%e8.1%) (Apprich et al, 2014;Kumar et al, 2016). Out of eight solid substrates tested, P. hysterophorous was found to induce maximum endoglucanase, b-glucosidase, and FPase during SSF and was selected for further optimization steps.…”

“…Xylanases are predominantly used for pre-bleaching of pulp to minimize the consumption of bleaching chemicals in pulp & paper industry. Industrial acceptance of any process principally depends on its cost effectiveness (El-shishtawy, Mohamed, Asiri, Gomaa, & Ibrahim, 2014;Gao et al, 2008;Gautam, Kumar, & Dutt, 2017;Kumar, Gautam, & Dutt, 2016;Singh, Singh, Kaur, Bansal, & Kaur, 2011). The higher production cost of an enzyme makes the final product expensive.…”

“…The higher bglucosidase activity prevents the accumulation of cellobiose in reaction mixture by converting it in to glucose which reduces the cellulase inhibition. (Kumar et al, 2016).…”

Over-Expression of the Thermobifida fusca β-Glucosidase in a Yarrowia lipolytica Transformant to Degrade Soybean Isoflavones

“…β-Glucosidases play pivotal roles in various biotechnological processes such as the reduction of cellobiose accumulation by the action of exo-glucanases to minimize the end-product inhibition [2] and the modification of cyanogenesis, glycolipids, and secondary metabolites [1]. They are involved in the bioconversion of lignocellulose to glucose, producing hydrogen with other exo-or endo-hydrolases and using glucose as an ingredient for fermentation [3,4]. They can also hydrolyze the β-glucosidic bonds of phenolic compounds conjugated to sugar residues via the hydroxyl groups [5][6][7].…”