Cellulase activity of a Lentinula edodes (Berk.) Pegl. strain grown in media containing Carboximetilcellulose or microcrystalline cellulose

Abstract

Endoglucanase and exocellobiohydrolase produced b Lentinula edodes (Berk.) Pegl. strain thatt was cultivated in carboxymetilcellulose (CMC) or microcrystalline cellulose (Avicel) liquid media. The concentration and type of cellulose influenced the enzyme activity and production. Extra-cellular cellobiase activity was not detected in CMC or Avicel media. This enzyme was detected in mycelial extracts only. With 1.7% Avicel liquid medium, the strain did not produce exocellobiohydrolase, but 74 µmol RBBR/mg protein/min was detected with 0.5% Avicel. The substitution of Avicel by 0.5% CMC reduced this activity. Endoglucanase also had maximum activity in 0.5% Avicel medium (approximately 820 UI/mg protein) after 96 h incubation. In supernatants from 0.5% CMC, the maximum activity attained was 200 UI/mg protein only.<br>Neste trabalho foram estudadas as atividades de endoglucanase, exocelobiohidrolase e celobiase em uma linhagem de Lentinula edodes (Berk.) Pegl. cultivada em meio líquido contendo carboximetilcelulose (CMC) ou celulose microcristalina (Avicel). Foram detectadas as atividades de endoglucanase e exocelobiohidrolase no sobrenadante das culturas crescidas tanto em meios contendo CMC como nos meios contendo Avicel, sendo observada a influência da concentração e do tipo de celulose. Não foi detectada atividade de celobiase nos sobrenadantes, sendo a mesma detectada somente no extrato micelial. Com uma concentração de 1,7% de Avicel, a linhagem estudada não demonstrou atividade de exocelobiohidrolase. Porém, à concentração de 0,5% obteve-se uma atividade de 74 µmol de RBBR/mg de proteína/min. Com a substituição de Avicel por CMC a 0,5%, a atividade de exocelobiohidrolase foi reduzida a menos de 50%. A máxima atividade de endoglucanase em sobrenadantes obtidos em meio com Avicel a 0,5% foi em torno de 800 UI/mg de proteína, após 96 horas de cultivo. Em sobrenadantes obtidos de meio com CMC, a atividade desta enzima foi de apenas 200 UI/mg de proteína

Use of vinasse and sugarcane bagasse for the production of enzymes by lignocellulolytic fungi

“…The lugol reacts with some polysaccharides (Hankin and Anagnostakis, 1975). In the presence of starch, a blue color is formed due to the potassium iodide, rendering the elementary iodine soluble in water through the formation of the I 3 -ion in the helix formed by the amylase (Pereira, et al, 2003). The starch was produced by the degradation of the carboxymethyl cellulose in the medium into lower molecular weight saccharides, consequently confirming the presence of cellulases.…”

Biomass, laccase and endoglucanase production by Lentinula edodes during solid state fermentation of reed grass, bean stalks and wheat straw residues

“…Regarding endoglucanase activity (which was weak relatively to laccase), Leatham (1985), Buswell et al (1996) andPereira Júnior et al (2003) reported L. edodes as a moderate cellulolytic enzyme producer, as it hydrolyzes hemicellulose more efficiently than cellulose (Moyson and Verachtert 1991;Silva et al 2005a). The positive relation of endoglucanase activity with the hemicellulose content of the substrates reported here support these previously drawn conclusions, as the weak endoglucanase production of L. edodes mycelia is accelerated in substrates as RG with high hemicellulose content.…”