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Lignocellulosic biomass is composed of three major biopolymers: cellulose, hemicellulose and lignin. Analytical tools capable of quickly detecting both glycan and lignin deconstruction are needed to support the development and characterization of efficient enzymes/enzyme cocktails. Previously we have described nanostructure-initiator mass spectrometry-based assays for the analysis of glycosyl hydrolase and most recently an assay for lignin modifying enzymes. Here we integrate these two assays into a single multiplexed assay against both classes of enzymes and use it to characterize crude commercial enzyme mixtures. Application of our multiplexed platform based on nanostructure-initiator mass spectrometry enabled us to characterize crude mixtures of laccase enzymes from fungi Agaricus bisporus (Ab) and Myceliopthora thermophila (Mt) revealing activity on both carbohydrate and aromatic substrates. Using time-series analysis we determined that crude laccase from Ab has the higher GH activity and that laccase from Mt has the higher activity against our lignin model compound. Inhibitor studies showed a significant reduction in Mt GH activity under low oxygen conditions and increased activities in the presence of vanillin (common GH inhibitor). Ultimately, this assay can help to discover mixtures of enzymes that could be incorporated into biomass pretreatments to deconstruct diverse components of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

State‐of‐the‐art flexible supercapacitors suffer from electrochemical and environmental performance issues including manufacturing expense limitations. Therefore, a highly effective and low‐cost strategy to develop supercapacitors is needed. To address this, a plant‐based, high‐performance, lightweight, low‐cost, quasi‐solid state, and composite electrode for flexible supercapacitors has been synthesized using the hydrothermal method. The composite electrode is made of alkali lignin and is decorated with MnO2 particles including an Al substrate. An Al/lig/MnO2 based anode and an Al/AC (activated carbon) based cathode were sandwiched using an inorganic polymer gel‐type electrolyte made of PVA/H3PO4 in order to assemble the supercapacitor. Synchrotron tomography and SEM are employed to study the detailed electrode morphology. Electrochemical impedance spectroscopy (EIS), cyclic charge‐discharge (CCD), and cyclic voltammetry (CV) have been used to assess electrochemical performance. Optimization is carried out using a series of lignin:MnO2 samples with varying constituent ratios. After 3000 charge‐discharge cycles, the highest specific capacitance value achieved at 40 mA g−1 reached 379 mF cm−2, (900 times reported). The capacitance retention, maximum energy density, and maximum power density are 80%, 6 Wh kg−1, and 355 W kg−1 respectively. Due to the superior electrochemical performance, the supercapacitor shows exceptional potential for future sustainable and green electronics. [ABSTRACT FROM AUTHOR]

miRNAs are endogenous regulatory factors that play pivotal roles in post-transcriptional regulation. However, their specific roles in early somatic embryogenesis (SE) remain unclear. Study of the SE system is fundamental for clarifying the molecular mechanisms in Dimocarpus longan. We identified 289 known miRNAs from 106 different miRNA families and 1087 novel miRNAs during early longan SE, including embryogenic callus (EC), incomplete pro-embryogenic culture (ICpEC), globular embryo (GE), and non-embryogenic callus (NEC). The abundances of known miRNAs were concentrated in GE. The differentially expression (DE) miRNAs showed five expression patterns during early SE. Largely miRNAs were expressed highly and specially in EC, ICpEC, and GE, respectively. Some miRNAs and putative target genes were enriched in lignin metabolism. Most potential targets were related to the pathways of plant hormone signal transduction, alternative splicing, tyrosine metabolism and sulfur metabolism in early longan SE. The regulatory relationships between dlo-miR166a-3p and DlHD-zip8, dlo-miR397a and DlLAC7, dlo-miR408-3p and DlLAC12 were confirmed by RNA ligase-mediated rapid amplification of cDNA ends. The expression patterns of eight DE miRNAs detected by qRT-PCR were consistent with RNA-seq. Finally, the miRNA regulatory network in early SE was constructed, which provided new insight into molecular mechanism of early SE in longan. [ABSTRACT FROM AUTHOR]

To expound the effects of existing endogenous or exogenous lignin on the performance of cellulose-based aerogels, both the cellulose aerogels and composite aerogels were fabricated by the dissolution-regeneration process by using LiCl/DMSO solvent system. The varying content of endogenous and exogenous lignin could lead to different aggregation states of cellulose, hemicellulose and lignin, thus causing different micromorphology and mechanical properties of cellulose aerogels and composite aerogels. The increased endogenous lignin in lignocellulose restricted the dissociation of cellulose and hemicellulose in dissolving process, which led to the appearance of enlarged pores, and then resulted in the decreased mechanical strength. However, for composite aerogels, externally added exogenous lignin deposited on the cellulose chains and then restricted the movement of polymer chains. It could not only bring about the increased pore size of aerogels, but also help to improve the mechanical strength, which was different from that of cellulose aerogels. Furthermore, two types of aerogels with higher lignin content both exhibited better adsorption capacity for methylene blue, especially for composite aerogel. This study provides a feasible way to tailor the morphology and physical properties of the aerogels by controlling the existential state or content of lignin. [ABSTRACT FROM AUTHOR]

In this study, one- and two-step pretreatments with alkali and acid were performed in the three Miscanthus species that exhibit distinct hemicelluloses levels. As a result, one-step with 4% NaOH or two-step with 2% NaOH and 1% H 2 SO 4 was examined to be optimal for high biomass saccharification, indicating that alkali was the main effecter of pretreatments. Notably, both one- and two-step pretreatments largely enhanced biomass digestibility distinctive in hemicelluloses-rich samples by effectively co-extracting hemicelluloses and lignin. However, correlation analysis further indicated that the effective lignin extraction, other than the hemicelluloses removals, predominately determined biomass saccharification under various alkali and acid pretreatments, leading to a significant alteration of cellulose crystallinity. Hence, this study has suggested the potential approaches in bioenergy crop breeding and biomass process technology. [ABSTRACT FROM AUTHOR]

Cellulose, lignin, raw bagasse fiber, and extracted bagasse fibers chemically processed with different concentrations of sodium hydroxide solution and treatment time were measured by thermogravimetry analysis (TGA). The thermal characteristics of these fibers were determined by thermogravimetry (TG) and derivative thermogravimetry (DTG) profiles and analyzed based on the onset degradation temperature, peak rate of thermal decomposition, and residual weight. According to the observations from the experimental data from TGA and DTG profiles and literature reports, it was found that higher content of cellulose and lower content of lignin would result in higher onset degradation temperature, higher peak rate of decomposition, and lower residual weight. Statistical analysis of the onset decomposition temperatures, peak rate of weight loss, and residual weights of different extracted bagasse fibers showed that most of their values were significantly different. The three-dimensional surface plots of onset decomposition temperature and peak rate of weight loss indicated that higher content of cellulose occurred in the bagasse fiber treated under the condition close to the region around 2 N NaOH for 2 hours or 1.5 N NaOH for 1.5 hours. [ABSTRACT FROM AUTHOR]

A facile and environmentally-friendly strategy for increasing antioxidant activity is a crucial issue for value-added lignin and lignin-carbohydrate complex (LCC) as alternative antioxidants. However, the antioxidant activities of lignin and LCC by the traditional solid-liquid extraction (SLE) methods were restricted by the relatively lower solubility induced from high molecular weight (Mw), and the less functional groups including, phenolic hydroxyl and carboxyl. To improve the antioxidantion of lignin and LCC, lithium chloride/dimethyl sulfoxide (LiCl/DMSO) solvent fractionation (LDSF) was conducted to increase the functional groups and reduce Mw, in which LiCl/DMSO acted triple roles as solvent, acid, and metal chloride catalyst for the depolymerization reaction synchronously. The β-O-4′ linkages were cleaved to release the phenolic hydroxyl, resulting in decreasing Mw; the hydroxyl of the side-chain of lignin was oxidized into carboxyl. Thus, the lignin (LD-RL) and LCC (LD-LCC) samples from LDSF had a higher syringyl (S)/guaiacyl (G) ratio, phenolic hydroxyl, and carboxyl contents, but less Mw than control groups from SLE. Consequently, they presented more excellent scavenging rates toward DPPH and ABTS radicals, up to 90%. This work provided panoramic perspectives and basics of the green and convenient approach to isolate and modify lignin and LCC for great antioxidantion with LDSF. • The lignin and LCC with high yield and antioxidantion were isolated from LDSF. • LiCl/DMSO acted triple roles as solvent, acid, and metal chloride catalyst. • Depolymerization induced by LiCl increased the functional groups and reduced Mw. • The higher S/G ratio, phenolic OH and COOH contents improved the antioxidantoin. [ABSTRACT FROM AUTHOR]

Effective removal of Cr(VI) pollution from aquatic environment is in pressing need because of the detrimental effect of Cr(VI) to human health. Herein, we report a facile two-step approach to synthesis MoS 2 /Lignin-derived Carbon (MoS 2 @LDC) nanocomposites for highly efficient elimination of Cr(VI) from aqueous solutions. The MoS 2 @LDC exhibited outstanding removal efficient for Cr(VI) (198.70 mg/g at pH = 2.0, T = 298.15 K and C Initial = 20.0 mg/L). 99.35% of Cr(VI) can be removed by the composites in 30 min. Thermodynamic and kinetic studies suggest the removal of Cr(VI) is through both adsorption and reduction. The performance of MoS 2 @LDC can be further enhanced by hydrogen plasma treatments, which was attributed to the sulfur vacancies induced improvement in the reduction activity of MoS 2 layer. The results of this work can guide the rational design of high-performance nanocomposite for efficient remediation of heavy metals in aquatic environment. ga1 • A facile two-step approach to synthesis MoS 2 /Lignin-derived Carbon (MoS 2 @LDC) composite. • The MoS 2 @LDC exhibits outstanding Cr(VI) removal performance. • The removal of Cr(VI) is through both adsorption and reduction. • Further enhancing the Cr(VI) removal performance of MoS 2 @LDC by H 2 plasma treatment. [ABSTRACT FROM AUTHOR]