Evaluation of the biocompatibile ionic liquid 1-methyl-3-methylimidazolium dimethylphosphite pretreatment of corn cob for improved saccharification

Abstract

Ionic liquid (IL) pretreatment of lignocellulose materials is a promising process in biomass conversion to renewable biofuel. More in-depth research involving environment-friendly IL is much needed to explore pretreatment green route. In our case, IL 1-methyl-3-methylimidazolium dimethylphosphite ([Mmim]DMP) was chosen as an environment-friendly solvent to pretreat corn cob in view of its biocompatibility with both lignocellulose solubility and cellulase activity. The pretreatment/saccharification process and in situ saccharification process involving [Mmim]DMP were efficiently performed in bioconversion of corn cob to sugars, and more than 70% saccharification rates were obtained. Furthermore, the fermentability of reducing sugars obtained from the hydrolyzates was evaluated using Rhodococcus opacus strain ACCC41043 (R. opacus). High lipid production 41-43% of cell dry matter was obtained after 30 h of cultivation. GC/ MS analysis indicated that lipids from R. opacus contained mainly long-chain fatty acids with four major constituent/ oleic acid, stearic acid, palmitic acid, palmitoleic acid which are good candidates for biodiesel. These elucidated that corn cob pretreated by IL [Mmim]DMP did not bring negative effects on saccharification, cell growth, and accumulation of lipid of R. opacus. In conclusion, the IL [Mmim]DMP shows promise as green pretreatment solvent for cellulosic materials.

The role of pretreatment in improving the enzymatic hydrolysis of lignocellulosic materials

“…Some ILs are powerful solvents for lignocellulosic materials, which can dissolve cellulose or lignocellulosic biomass forming homogeneous solutions (Zavrel et al, 2009). Li et al (2010) investigated the effect of various ILs pretreatment on enzymatic hydrolysis of corn cob. It was found that ILs containing phosphate or chloride groups enhanced the yield of reducing sugar significantly.…”

Effects of selected ionic liquids on lipid production by the oleaginous yeast Rhodosporidium toruloides

“…Recently, pretreatment with ionic liquids (ILs) has been received intensive study (KleinMarcuschamer et al, 2011), and more biocompatible ILs have been developed. Regardless of detailed procedures (Li et al, 2010;Ninomiya et al, 2012;Wang et al, 2011), however, ILs are carried over and present at various concentrations in the stream used for fermentation ). This may cause unacceptable effects.…”

Lipid Extraction Methods from Microalgae: A Comprehensive Review

“…Earlier, the applications of microwave radiation were limited to the digestion of samples for measuring trace metals (Huffer et al, 1998) and extraction of organic contaminants (Marcato and Vianello, 2000). The feasibility of extracting lipids using microwave irradiation was first reported in the mid-1980s (Ganzler et al, 1986).…”