Synergistic enzymatic and microbial lignin conversion

Abstract

The utilization of lignin for fungible fuels and chemicals represents one of the most imminent challenges in modern biorefineries.

Structural Characterization of Lignin and Its Degradation Products with Spectroscopic Methods

“…Enzymatic lignin degradation has several advantages such as mild conditions and potentially fewer inhibitors for microbes. However, the degradation of lignin in LCBM still gave a very low yield of fragmented and soluble lignin, which may due to the limitations on efficient electron transfer [28] in the process.…”

“…Furthermore, a significant reduction in the weight-average molecular weight (M w ) of extracted lignin was also achieved. Synergistic effects were found in the combination of pretreatments to enhance the isolation or conversion of lignins [28,46]. In the sequential fractionation of Tamarix spp., MWL, organosolv lignin, and alkaline lignin were conducted with dioxane, alkaline organosolv, and alkaline solutions, respectively.…”

Biotransformation of lignin: Mechanisms, applications and future work

“…68,99 Other than single enzymes, fungal secretome (i.e., enzyme mixture) was also directly added into the lignin fermentation broth, which led to a reduction of lignin molecular weight by more than 60%. Fungal ligninolytic enzymes with strong oxidative ability can be supplemented into lignin fermentation system to facilitate the destruction of complex lignin molecules.…”

A Review on The Bioconversion of Lignin to Microbial Lipid with Oleaginous Rhodococcus opacus

“…To obtain smaller molecular weight Kraft lignin, oxygen-pretreatment (O 2 -pretreatment) was carried out on Kraft lignin under alkaline conditions which lowered the molecular weight of the lignin and when treated with R. opacus resulted in increased oleaginicity (14%) and an increase in lipid titers (0.07 mg/ml) [57] (Table 1, #4). Alternatively, Zhao supplemented R. opacus fermentation with Kraft lignin with laccases which resulted in an increase in lipid titers (0.15 mg/ ml) [78] (Table 1, #5). Laccases aid in lignin depolymerization allowing for selective degradation of different lignin functional groups probably improving the usage of the lower molecular weight lignin molecules [78].…”

“…Alternatively, Zhao supplemented R. opacus fermentation with Kraft lignin with laccases which resulted in an increase in lipid titers (0.15 mg/ ml) [78] (Table 1, #5). Laccases aid in lignin depolymerization allowing for selective degradation of different lignin functional groups probably improving the usage of the lower molecular weight lignin molecules [78].…”