Production and Purification of Cellulase from Aspergillus nidulans AJSU04 under Solid-state Fermentation using Coir Pith

Coir pith is an organic matter which originates from the tropical hemisphere, especially from southeast Asia where coconut oil production is extensive. For professional oil winning companies, the husk of the nut is a waste product. These coconut husks mainly consist of coir pith and coir fibers. Initially, coir pith was considered a waste but now research has established widespread applications for it. Being an agro-waste from the coir industry, coir pith serves as a renewable source.1 Accumulation of coir pith near coir retting factories causes solid waste pollution problems mainly due to the ligno-cellulosic compounds present in them. The lignin (31 %) and cellulose (27 %) that they contain is responsible for their slow degradation.2 Over the last few years, environmental concerns have increased attention toward using coir pith as an alternative substrate with orientation towards agricultural needs. Thus, the conversion of such agricultural wastes into useful products may decrease the problems they cause. This study deals with the utilization of coir pith for cellulase production. But the lignin present in the coir pith was observed to interfere with hydrolysis by irreversibly binding the hydrolytic enzymes, thereby blocking access to cellulose. Pretreatment of coir pith increases the crystallinity of cellulose, thus removing lignin and enabling its enzymatic degradation. In addition, pretreatment may increase the surface area of the cellulose thereby enhancing its reactivity with the enzyme and thus its transformation.3 Cellulose is commonly degraded by an enzyme called cellulase.4 Several studies have been carried out to produce cellulolytic enzymes from biowaste using degradation process by using microorganisms including fungi, such as Trichoderma, Penicillium, and Aspergillus spp.5 The commercial use of cellulases is dependent on the following: high titer and good enzymatic activity, low production cost and feasible mass production. Cellulases are inducible enzymes and their synthesis is strongly repressed by soluble sugars. Cellulases are imperative enzymes not only for their potent applications in different sectors, like industries of food processing, animal feed production, pulp and paper production, detergent and textile, but also for the significant role in the bioconversion of agricultural wastes into sugar and bioethanol. The cellulase enzyme derived from a thermophilic anaerobe Clostridium thermocellum Production and Purification of Cellulase from Aspergillus nidulans AJSU04 under Solid-state Fermentation using Coir Pith