Degradation and selective ligninolysis of wheat straw and banana stem for an efficient bioethanol production using fungal and chemical pretreatment

Abstract

Lignocelluloses from agricultural, industrial, and forest residues constitute a majority of the total biomass present in the world. Environmental concerns of disposal, costly pretreatment options prior to disposal, and increased need to save valuable resources have led to the development of value-added alternate technologies such as bioethanol production from lignocellulosic wastes. In the present study, biologically pretreated (with the fungus, Pleurotus ostreatus HP-1) and chemically pretreated (with mild acid or dilute alkali) wheat straw (WS) and banana stem (BS) were subsequently subjected to enzymatic saccharification (with mixture of 6.0 U/g of filter paper cellulase and 17 U/g of β-glucosidase) and were evaluated for bioethanol production using Saccharomyces cerevisiae NCIM 3570. Biological and chemical pretreatments removed up to 4.0–49.2 % lignin from the WS and BS which was comparatively higher than that for cellulose (0.3–12.4 %) and for hemicellulose (0.7–21.8 %) removal with an average 5.6–49.5 % dry matter loss. Enzymatic hydrolysis yielded 64–306.6 mg/g (1.5–15 g/L) reducing sugars from which 0.15–0.54 g/g ethanol was produced from Saccharomyces cerevisiae NCIM 3570.

Influence of nitrogen sources on the enzymatic activity and grown by Lentinula edodes in biomass Eucalyptus benthamii

“…In this study xylanases activities were lower than those studies Silva et al (2005) and Thakur et al (2012) and superior to Chicatto et al (2014). This activity was not significant for L. edodes compared with exo and endocellulases.…”

Pretreated of banana pseudo-stem as raw material for enzymatic hydrolysis and bioethanol production

“…The cellulose was converted to reduction sugar at hydrolysis process followed by fermentation of the sugar to bioethanol. Alkali pretreatment can increase ethanol concentration was also reported by a study by [15]. …”

Production of lignocellulolytic enzymes from floriculture residues using Pleurotus ostreatus

“…To exploit the potential of lignocellulose as feedstock to produce high added-value products, a physical, chemical or biological pretreatment process is always necessary to modify its three-dimensional structure. Some biological pretreatments have been studied, among these; degradation using enzymes produced by fungi (Stajić et al 2006, Membrillo et al 2008, Bettin et al 2011, Větrovský et al 2013, including the lignocellulosic degradation using P. ostreatus (Isikhuemhen & Mikiashvilli 2009, Quevedo-Hidalgo 2012, Thakur et al 2013.…”

“…Elisashvili et al (2006) studied the production of cellulase, xylanase, laccase and manganese peroxidase in submerged fermentation of mandarin peels and tree leaves. Thakur et al (2013) reported the production of ligninolytic enzymes using P. ostreatus from biologically and chemically pretreated wheat straw and banana stem substrates.…”