Use of elephant grass (Pennisetum purpureum) as substrate for cellulase and xylanase production in solid-state cultivation by Penicillium echinulatum

Abstract

-The high cost of the enzymes used for the hydrolysis of lignocellulosic biomass is one of the bottlenecks in the production of second-generation ethanol and the use of local biomass, such elephant grass, can help to reduce this cost. In this investigation elephant grass biomass was evaluated as a carbon and inducer source of production of cellulases and xylanases by the fungus Penicillium echinulatum strain 9A02S1 in solid-state cultivation. The highest filter paper activity (13.26 U.g -1 dry matter) and β-glucosidase activity (138.34 U.g -1 dry matter) were obtained on the fifth day of cultivation, in medium containing biomass pre-treated with sulfuric acid and untreated, respectively. The highest endoglucanase activity was 158.44 U.g -1 dry matter in the presence of elephant grass pre-treated with sulfuric acid. The xylanase activity was highest with medium that was formulated with 75% untreated elephant grass and 25% wheat bran (372.62 U.g -1 dry matter). In conclusion, the results showed that it is possible to obtain large amounts of cellulases and xylanases using a cosmopolitan and very low cost substrate such as elephant grass.

Biotechnology and its Applications for Penicillium echinulatum: a Systematic Review

“…Even though this mechanism is blocked, xylanase activity may still be initiated xylanases by combining 3EG:1WB without pretreatments, and β-glucosidase with untreated EG. These results indicate an influence caused by structural changes to the biomass, especially for the cellulolytic enzymes production, with the exception of β-glucosidases (MENEGOL et al, 2017). In accordance with previous sugarcane bagasse papers, elephant grass displayed similar xylanase activity behavior, where a higher value is achieved by employing no pretreatment (CAMASSOLA; DILLON, 2010).…”

“…Besides steam explosion, EG was also washed with distilled water afterwards in all cases (SCHOLL et al, 2015a). At last, in a work by Menegol et al (2017), EG was submitted to different pretreatments, obtaining the highest enzymatic activity of endoglucanase and FPA after sulfuric acid pretreatment, Still on the work carried out by Reis et al (2013), the maximum enzyme activity for FPA, endoglucanase and xylanase were obtained in a fed-batch culture with 40 g l -1 of cellulose, while for β-glucosidases both batch and fedbatch experiments using 60 g l -1 of cellulose. The fed-batch technique has shown to be more adequate, probably due to the low levels of glucose kept in the culture.…”