Sugar cane bagasse pretreatment: An attempt to enhance the production potential of cellulases by <i>Humicola insolens</i> TAS-13

Abstract

Pretreatment of the cellulosic substrate has miracle effect on the enhancement of cellulase production by fungal strains. A thermophilic strain of Humicola insolens TAS-13 was locally isolated and was tested for cellulases production under solid-state fermentation conditions using sugar cane bagasse as substrate. The cultural conditions for the H. insolens were also optimized for the higher rate of cellulase secretion. In order to enhance the production rate of heterogenous cellulosic proteins, bagasse was pretreated with NaOH, H 2 SO 4 , H 2 O 2 and H 2 O 2 +1.5%NaOH. The pretreatment of bagasse with 2.0% H 2 O 2 along with 1.5% NaOH enhanced the biosynthesis of cellulases by H. insolens. Production rate was also optimized with different parameters like thickness of fermentation medium, initial pH, incubation time and temperature. The thickness of the fermentation medium of 0.8 cm (10 g) with pH range of 5.5 was found to be better for enhanced production at 50°C. The yield of the enzyme was reached maximum with CMC-ase (18.98 U/g/min), FP-ase (13.63 U/g/min), -glucosidase (19.54 U/g/min) 72 h after inoculation.

Process optimization for enhanced production of cellulases form locally isolated fungal strain by submerged fermentation

“…The small pieces of sugar cane bagasse were sun dried and after this treated with sodium hydroxide (4%) by dipping in the solution for 24 hours. The sample was then washed with water and dried in oven for 3-4 h at 60°C (Haq et al 2006).…”

Enhanced production of β- glucosidase by locally isolated fungal strain employing submerged fermentation

“…The sample of sugar cane bagasse was chopped into small pieces and sun dried. Pretreatment of sugar cane bagasse was carried by dipping in 4% solution of sodium hydroxide for 24 h. After this washed the sample with distilled water and dried in oven at 60 °C for 3-4 h (HAQ et al, 2006).…”

Isolation of Mercury-Resistant Fungi from Mercury-Contaminated Agricultural Soil

“…Both species belong to phylum Ascomycota, order Eurotiales, Family Trichocomaceae. Aspergillus niger and A. flavus are soil fungi that are often used as bioremediation agents for Hg-contaminated soil [9,10]. and isolate B was Aspergillus flavus (Figure 4).…”

“…Fungi have been widely used to remediate soil contaminated by heavy metal through several mobilization mechanisms. The soil fungi Aspergillus flavus [9], Aspergillus niger, Trichoderma viride, Humanicola insolens [10], Fusarium oxysporum [11], and Rhizopus arrhizus [12] have been shown to be capable of carrying out heavy metal biotransformation.…”