Source Of Lignocellulosic Biomass Research Articles

Synthesis and characterization of novel lignocellulosic biomass-derived activated carbon for dye removal: Machine learning optimization, mechanisms, and antibacterial properties

Transforming waste materials into valuable products plays a crucial role in promoting sustainability and protecting environment. In this study, activated carbon derived from sugarcane bagasse, a lignocellulosic biomass source, was coated with iron and manganese for the adsorption and photodegradation of Acid Black 1 (AB1) dye from aqueous solutions. The effects of various parameters were investigated using Central Composite Design (CCD) and a Multi-Layer Perceptron (MLP) algorithm. The results of the characterization indicated that the iron and manganese particles were uniformly dispersed on the activated carbon. While CCD determined ideal parameters to be an initial concentration of 20.15 mg L−1, a dose of 25 mg/30 mL, a pH of 5, and a time of 40 min, the MLP Algorithm proposed slightly different conditions: an initial concentration of 26.66 mg L−1, dose of 25 mg, pH of 5.0, and a time of 25.05 min. Despite these differences, both methods projected impressive AB1 removal efficiency, 100 % for CCD and 99.02 % for MLP, underscoring the potential effectiveness of these strategies in AB1 mitigation. Concentration emerged as the predominant factor influencing the removal process, as determined by the MLP algorithm. The results showed that the major active species in the degradation of AB1 were ecb− and •O2−, while hvb + species also participated to some extent, and triethanolamine (TEOA) had a minor effect on the degradation efficiency. The nanocomposite exhibited a high antibacterial activity against Staphylococcus aureus, resulting in a large zone of inhibition. The optimized nanocomposite could be used as an effective nanomaterial to remove hazardous contaminants.

Lignocellulose hydrothermal artificial humic acid production: Reaction parameters screening and investigation of model/real feedstock

Utilizing relatively mild hydrothermal conversion technique (under optimized conditions, 200 °C, 4 h, 1:10 solid-liquid ratio, 0.5 M NaOH), lignocellulosic biomass can be efficiently transformed into humic acids, thereby significantly enhancing its utilization. Additionally, this approach provides a means for precise manipulation of the composition and properties of the resulting humic acids. In this comprehensive study, lignocellulosic biomass, comprising various attributes like coniferous, broadleaf, and grassy species, as well as model components like cellulose, hemicellulose, and lignin, underwent hydrothermal reactions to produce humic acids. Firstly, a systematic evaluation was conducted to determine the influence of operational parameters on the formation of humic acids. Subsequently, the characteristics of humic acids derived from diverse lignocellulosic biomass sources were analyzed and benchmarked against commercial humic acids. Based on the empirical findings, a mechanistic pathway for the generation of humic acids was figured out. The results indicate that the primary stages in the hydrothermal conversion of lignocellulosic biomass to humic acids involve initial hydrolysis into smaller molecular components, followed by further reactions leading to the formation of humic acids. Notably, the interplay between cellulose, hemicellulose, lignin, and other minor components, such as tannins and pectins, plays a pivotal role in the synthesis of humic acids. The characterization of the derived humic acids revealed several noteworthy distinctions from commercial products. In the infrared spectroscopy (FTIR) and elemental analysis (EA) characterization, the synthetic humic acid has more oxygen functional groups, alkane groups and aromatic structures. In the X-ray photoelectron spectroscopy (XPS), the synthetic humic acid has more diverse forms and proportions of elements. In thermogravimetric analysis (TGA), the synthesized humic acid has higher thermal stability. The synthetic humic acid has a rougher surface microstructure. The synthetic humic acid has higher fluorescence intensity in three-dimensional fluorescence spectrum (3D EEM). Lignocellulose biomass raw materials with high wood quality content can obtain higher humic acid yield, but the interaction of cellulose, hemicellulose, lignin and other group components (such as tannins, pectin, etc.) in the hydrothermal process plays an important role in the generation of humic acid. This research offers valuable insights into the chemically driven production of humic acids and the strategic control of their properties, based on the structural and compositional nuances of the raw materials.

Effect of Different Parameters on Enzymatic Hydrolysis of Hazelnut Shells

In the last few decades, the increasing levels of environmental pollution have prompted a shift towards alternative energy sources and biobased solutions, such as lignocellulosic biomass. Lignocellulosic biomass (LB) is primarily derived from plants and is composed mainly of polysaccharides, namely cellulose, hemicellulose, and the aromatic polymer lignin. Hazelnut shells (HS), with a high lignin content of 43%, hemicellulose of 30%, and cellulose of 26%, hold promise as a valuable source of LB. In order to process those LB, lignin and hemicellulose are separated using various treatment methods. However, instead of being used solely for combustion, lignin-containing materials can be valorized for a range of purposes, from biomedical applications to the energy sector. In this study, the enzymatic hydrolysis of HS was conducted over different time periods (24, 48, 72, and 96 hours), at different temperature values with varying enzyme concentrations (0.05, 0.1, and 0.25 mL of cellulase/xylanase enzyme cocktail). To enhance the enzymatic hydrolysis, an alkaline pretreatment method using sodium hydroxide (NaOH) was employed. The results demonstrate that the maximum sugar concentration was achieved at 50°C, after 72 hours, and with a cellulase/xylanase cocktail concentration of 0.1 mL.

Advancements in biomass valorization in integrated biorefinery systems

AbstractThe utilization of lignocellulosic biomass for the generation of diverse value‐added biochemicals and biofuels is crucial in modern biorefineries and bioenergy initiatives, contributing significantly to the pursuit of a climate‐neutral future. Agricultural, forest and industrial sources of lignocellulosic biomass serve as exceptionally renewable precursors in biorefinery processes. In spite of its abundance, the effective breakdown of biomass poses a significant challenge. Thus, it is essential to integrate various unit processes, including biochemical, thermochemical, physical, enzymatic and catalytic conversion, to generate a wide array of bio‐based products. Intensive integration of these processes not only enhances yield and reduces reaction time but also proves to be economically efficient. Furthermore, these process integration approaches may contribute to the establishment of a circular bioeconomy through biorefineries, effectively reducing both bioresource waste and greenhouse gas emissions. This review offers fundamental insights into biomass and its chemistry, with a detailed discussion on lignocellulosic conversion systems. It explores how integrating conversion processes can facilitate the transition toward a circular economy. Additionally, it summarizes the challenges and prospects associated with advancing integrated biorefineries and circular economy principles to achieve complete biomass valorization.

Chemical approaches for the biomass valorisation: a comprehensive review of pretreatment strategies.

The most abundant natural renewable resource in the world, lignocellulosic biomass (LCB), has the potential to be exploited as a substitute green feedstock for the synthesis of various chemicals, materials, and biofuels. The annual global production of 13 billion tonnes of LCB offers an opportunity to cater to the increasing energy and materials requirement of process industries and also restricts the discharge of greenhouse gases. Although LCB is enriched with valuable ingredients such as cellulose, lignin, and hemicellulose, its recalcitrant nature limits its efficient utilisation. These components of LCB are strongly interlinked with each other, which resists their isolation and conversion valorisation into useful products. To disrupt the complicated structure of LCB and to isolate the lignocellulosic components in pure form, pretreatment is a crucial process in the bio-refinery, ensuring the economic feasibility of downstream processes. This review provides an outline of the structure, composition, and various sources of LCB; and the necessity of the pretreatment. Moreover, this article provides an in-depth analysis of the underlying mechanisms, advantages, and limitations of various pretreatment methods, such as physical, chemical, biological, and physicochemical. Further, the impact of chemical pretreatment techniques on the physicochemical characteristics of the material that is extracted from the biomass is also covered in detail through the rigorous evaluation of performance metrics, including substrate digestibility, sugar yield, inhibitor production, and energy requirements. This review provides a balanced and comprehensive overview of the state-of-the-art pretreatment strategies and their impact on biomass valorisation that will be useful to the scientists, engineers, and policy makers interested in biomass conversion technologies.

Impacts of in-vitro zebularine treatment on genome-wide DNA methylation and transcriptomic profiles in Salix purpurea L.

Renewable energy resources such as biomass are crucial for a sustainable global society. Trees are a major source of lignocellulosic biomass, which can vary in response to different environmental factors owing to epigenetic regulation, such as DNA C-methylation. To investigate the effects of DNA methylation on plant development and wood formation, and its impacts on gene expression, with a focus on secondary cell wall (SCW)-associated genes, Salix purpurea plantlets were cloned from buds derived from a single hybrid tree for both treatment and control conditions. For the treatment condition, buds were exposed to 50 μM zebularine in vitro and a combined strategy of whole-genome bisulfite sequencing (WGBS) and RNA-seq was employed to examine the methylome and transcriptome profiles of different tissues collected at various time points under both conditions. Transcriptomic and methylome data revealed that most of the promoter and gene body demethylation had no marked effects on the expression profiles of genes. Nevertheless, gene expression tended to decrease with the increased methylation levels of genes with highly methylated promoters. Results indicated that demethylation is less evident in centromeric regions and sex chromosomes. Promoters of secondary cell wall-associated genes, such as 4-coumarate-CoA ligase-like and Rac-like GTP-binding protein RHO, were differentially methylated in the secondary xylem samples collected from two-month potted treated plants compared to control samples. Our results provide novel insights into DNA methylation and gene expression landscapes and a basis for investigating the epigenetic regulation of wood formation in S. purpurea as a model plant for bioenergy species.

PINEPEAT from Pinus roxburghii (Chir Pine) foliage

Pinus roxburghii commonly known as Chir Pine is a coniferous tree native to the Himalayas. Pine needles shed from pine trees decay very slowly, form a carpet on the forest floor and are a major cause of frequent forest fires. The abundantly available unutilized pine needles are rich source of lignocellulosic biomass, goes waste, and its management through sustainable utilization has been a challenge.In the present study, pine needles were fibrillated by using laboratory disc refiner without any chemical treatment under different refiner passes from 0.10 to 0.40 mm to prepare pinepeat. The biomasses under different refiner passes were characterized for pH (6.2–6.5), freeness (481–821 ml), water absorbency (350–580 %), drainage time (9.10–16.99 sec), carbon (45.08 %), nitrogen (0.93 %), hydrogen (6.49 %), sulfur (0.13 %) content and C/N ratio (50.86 %). Anatomical characteristics of pine needle and pinepeat were also examined. The study reported significant change in morphology of pine needles after refining treatment wherein tissues turned into flattened, fibrillated and separated in short groups, increasing the surface area of the fragmented biomass. Application of processed pinepeat as amendments in nursery substrates was further assessed. The significantly higher growth parameters in pinepeat in comparison to conventional growing media suggests pinepeat as an additional environmentally sustainable choice for nursery operations in near future. The utility of pinepeat in this way is imperative for environment waste management and would turn into an alternative, renewable, and reliable growing media as amendments in nursery substrates.

Delignification of Different Lignocellulosic Biomass Using Hydrogen Peroxide and Acetic Acid (HPAC)

Lignocellulosic biomass will soon become the key source of feedstock for bioenergy to combat the impact of global warming and the depletion of fossil fuel resources. Lignin separation costs have been a key obstacle to bioenergy generation from lignocellulosic biomass. Pulp and paper, biofuel, and biomaterials sectors depend on wood delignification. This study examines delignification trends and advances, including standard and new methods. The study begins by explaining how delignification improves wood processability and value. It describes lignin's chemical structure and properties, highlighting its role in wood's mechanical and chemical qualities. Lignin from diverse lignocellulosic biomass sources is delignified using hydrogen peroxide and acetic acid in this study. A 1:1 hydrogen peroxide-acetic acid volume ratio was used after particle reduction. Experimental results show 96%, 89%, and 80% lignin removal efficiency for Ako, Mahogany, and mixed sawdust, respectively. A 30-minute reaction at 80°C yielded these results. The hydrogen peroxide-acetic acid mixture dignifies well and may be used in lignocellulosic biomass processing. This study also provides insights into optimizing delignification procedures and suggests approaches to improve the industrial use of lignocellulosic biomass. This study reveals that HPAC dignifies wood well. Understanding HPAC's role in the delignification of wood products could lead to developing an HPAC-based pretreatment technique that lowers the cost of biofuel generation from lignocellulosic biomass.

Enzymatic hydrolysis of cellulose banana stem (alkaline microwave-assisted pre-treatment)

The banana stem waste holds immense promise as a readily available and abundant source of lignocellulosic biomass, making it a compelling alternative for biofuel and biochemical applications. Therefore, this study focuses on investigating the impact of both time and substrate loading on the enzymatic hydrolysis of banana stem cellulose that has undergone alkaline microwave-assisted pre-treatment. The pre-treatment method involves subjecting the biomass to 5% KOH for 30 min, followed by microwave exposure at 300 W for 5 min, a process aimed at enhancing the accessibility of cellulose. Enzymatic hydrolysis experiments were carried out utilizing cellulase enzymes derived from Aspergillus niger, with variations in hydrolysis times (ranging from 5 to 45 h) and enzyme-to-substrate ratios (ranging from 1:1 to 1:10). The results of this investigation revealed a substantial improvement in hydrolysis efficiency, owing to the synergistic effects of alkaline microwave-assisted pre-treatment, signifying enhanced cellulose accessibility. Notably, the highest concentration of reducing sugars (1.3 mg mL−1) was achieved at a substrate-to-enzyme ratio of 1:1 and a hydrolysis duration of 45 h. These findings provide valuable insights into the conversion of lignocellulosic biomass, emphasizing the potential of integrated pre-treatment strategies for sustainable biorefinery applications. This research contributes to advancing our understanding of lignocellulosic biomass utilization, offering a promising avenue for biofuel and biochemical production from banana stem waste.

Efficient conversion of an underutilized low-lignin lignocellulosic biomass to cellulose nanocrystals and nanofibers via mild chemical-mechanical protocols

The production of high-quality nanocellulose (NC) from an underutilized low-lignin lignocellulosic biomass source, Phalaris aquatica L., was investigated via three conversion protocols. Initially, a conventional chemical protocol (Scenario I) was optimized using statistically designed experiments, and cellulose nanocrystals (CNCs) that exhibited an adequate crystallinity index (CI) were produced under mild conditions: short processing times, reduced temperatures and decreased use of chemicals and solvents. Hydrolysis temperature was found to contribute significantly to the variation of CI. Furthermore, two additional scenarios based on a planetary ball mill were comparatively applied, namely a combined chemical-mechanical (Scenario II) and an alternative (Scenario III) protocol, in which the ball milling step followed or replaced the acid hydrolysis step, respectively. In Scenarios II and III the NC structure was modified to cellulose nanofibrils (CNFs) and microfibrillated cellulose (MFC), respectively. Accordingly, the three different NC grades (CNCs, CNFs and MFC) were correlated with the three conversion protocols.

A detailed sensitivity analysis identifies the key factors influencing the enzymatic saccharification of lignocellulosic biomass

Corn stover is the most abundant form of crop residue that can serve as a source of lignocellulosic biomass in biorefinery approaches, for instance for the production of bioethanol. In such biorefinery processes, the constituent polysaccharide biopolymers are typically broken down into simple monomeric sugars by enzymatic saccharification, for further downstream fermentation into bioethanol. However, the recalcitrance of this material to enzymatic saccharification invokes the need for innovative pre-treatment methods to increase sugar conversion yield. Here, we focus on experimental glucose conversion time-courses for corn stover lignocellulose that has been pre-treated with different acid-catalysed processes and intensities. We identify the key parameters that determine enzymatic saccharification dynamics by performing a Sobol's sensitivity analysis on the comparison between the simulation results from our complex stochastic biophysical model, and the experimental data that we accurately reproduce. We find that the parameters relating to cellulose crystallinity and those associated with the cellobiohydrolase activity are predominantly driving the enzymatic saccharification dynamics. We confirm our computational results using mathematical calculations for a purely cellulosic substrate. On the one hand, having identified that only five parameters drastically influence the saccharification dynamics allows us to reduce the dimensionality of the parameter space (from nineteen to five parameters), which we expect will significantly speed up our fitting algorithm for comparison of experimental and simulated saccharification time-courses. On the other hand, these parameters directly highlight key targets for experimental endeavours in the optimisation of pre-treatment and saccharification conditions. Finally, this systematic and two-fold theoretical study, based on both mathematical and computational approaches, provides experimentalists with key insights that will support them in rationalising their complex experimental results.

Optimisation study of Ulmus pumila woody biomass fractionation by steam explosion for bioproducts production

Ulmus pumila represents a promising lignocellulosic biomass source for biofuels and bioproducts production since it can grow in low rainfall and extreme temperature zones. A first step in the conversion process is biomass fractionation to enhance the performance of the hydrolysis and subsequent biological conversion steps. The aim of this work is to optimise the main variables (temperature, residence time and the addition or not of sulphuric acid) of steam explosion to pretreat Ulmus pumila biomass. The optimal conditions to maximise both glucose and xylose recovery were 204.8 °C and 30 mg H2SO4/g biomass, obtained through a multilevel factorial design of experiments. Additionally, enzymatic hydrolysis using high solid loads (15% and 20% (w/w)) and different enzyme doses was studied. As a result, steam explosion at optimal conditions followed by enzymatic hydrolysis with 20% solid loading and 60 mg protein/g cellulose of enzyme allow the recovery of 70% of the potential sugars.

A systematic review of lignocellulosic biomass for remediation of environmental pollutants

Lignocellulosic wastes are the most promising feedstock, as they are the most inexpensive and abundantly renewable natural resource. The abundance of cellulose, lignin, and hemicellulose in feedstocks has been shown to be effective in eliminating persistent contaminants. Environmental issues, including the accumulation of agricultural waste, waste water treatment, and air pollution, could be resolved by producing value-added products like activated carbon from these wastes. Several biomass wastes were used to produce activated carbon using a two-step processing method that involved oxygen-free carbonisation and activation. This study examines the methods for making biochar from different lignocellulosic biomass sources. Furthermore, biochar modification significantly modifies surface area and pore volume. To determine the fundamental characteristics of biochar and to evaluate its potential for use in a variety of environmental applications, physical and chemical characterizations are required. Various widely used modern analytical techniques, such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), nuclear magnetic resonance spectroscopy (NMR), Brunauer-Emmett-Teller (BET), and Raman spectroscopy, have been reviewed in this work. The potential mechanisms through which lignocellulosic biochars may absorb pollutants are outlined. In general, this review highlights the significance and potential of activated carbon formed from waste products for environmental remediation, demonstrating that biomass-originated activated carbon could have a significant impact on increasing economic viability and efficiently protecting the environment.

An Overview of Lignocellulose and Its Biotechnological Importance in High-Value Product Production

Lignocellulose consists of cellulose, hemicellulose, and lignin and is a sustainable feedstock for a biorefinery to generate marketable biomaterials like biofuels and platform chemicals. Enormous tons of lignocellulose are obtained from agricultural waste, but a few tons are utilized due to a lack of awareness of the biotechnological importance of lignocellulose. Underutilizing lignocellulose could also be linked to the incomplete use of cellulose and hemicellulose in biotransformation into new products. Utilizing lignocellulose in producing value-added products alleviates agricultural waste disposal management challenges. It also reduces the emission of toxic substances into the environment, which promotes a sustainable development goal and contributes to circular economy development and economic growth. This review broadly focused on lignocellulose in the production of high-value products. The aspects that were discussed included: (i) sources of lignocellulosic biomass; (ii) conversion of lignocellulosic biomass into value-added products; and (iii) various bio-based products obtained from lignocellulose. Additionally, several challenges in upcycling lignocellulose and alleviation strategies were discussed. This review also suggested prospects using lignocellulose to replace polystyrene packaging with lignin-based packaging products, the production of crafts and interior decorations using lignin, nanolignin in producing environmental biosensors and biomimetic sensors, and processing cellulose and hemicellulose with the addition of nutritional supplements to meet dietary requirements in animal feeding.

A review of nanocellulose modification and compatibility barrier for various applications

Nanocellulose is increasingly important due to its abundance and sustainability sources, outstanding physicochemical properties, low density, high specific surface area, and easily modified surface chemistry. Nanocellulose is obtained from various sources, such as plants, algae, and bacteria, with plant-derived nanocellulose being the most common. Their presence significantly benefits many applications, especially in developing advanced materials for high end-use. Despite these benefits, the intrinsic hydrophilic behavior complicates dispersion in hydrophobic polymer matrices due to aggregation issues that result in deterioration properties. Nanocellulose modification and surface tuning are identified as fundamental approaches for improving the compatibility of the interfacial interaction between nanocellulose and polymer matrix to impart new functionalities to novel advanced materials. This article offers insight into nanocellulose by highlighting various lignocellulosic biomass sources and their chemical constituents. Three categories of nanocellulose are discussed in this review, including cellulose nanocrystals, cellulose nanofibrils, and bacterial nanocellulose. This article also featured several methods for promoting surface modification of nanocellulose to overcome the compatibility barrier between nanocellulose and polymer matrix to achieve a balanced hydrophilic-hydrophobic behavior. A few recent and emerging applications of nanocellulose-based composites are also presented in this review.

Isolation of nanocellulose from Dodonaea viscosa plant: structural and thermal properties

Abstract In this research work, cellulose was isolated from Dodonaea viscosa plant by means of various chemical processes followed by the preparation of nanocellulose through sulfuric acid hydrolysis. These chemical processes begin with the removal of non-cellulosic material such as lignin, pectin, crude wax, and hemicellulose followed by alkaline treatment and chlorine-free bleaching methods. Fourier transform infrared (FTIR) spectroscopy showed the successful isolation of cellulosic material after removing hemicellulose, lignin, and other extractives. Thermogravimetric analysis (TGA) elucidated the thermal degradation profile of the cellulose-based materials obtained after various chemical procedures at each step. Additionally, nanocellulose was prepared from cellulosic material using acid hydrolysis, and its structural and thermal properties were discussed. Nanocellulose extraction from the lignocellulosic biomass sources and its further utilization has been the subject of intensive research as the global community needs the use of green chemistry principles in recent life. Nanocellulosic material due to its unique characteristics and properties is of great importance and has many applications in various industries, including materials science and engineering.

Optimization of hydrothermal-assisted alkali process for enhanced xylan recovery from banana fiber biomass

Banana fiber is a rich lignocellulosic biomass source that has not been widely explored. The hemicellulose components (15 - 20 %) of banana fiber can be a feedstock for producing high-value commodity chemicals. Hemicellulose is extracted by physical, chemical, and biological methods, in which combining hydrothermal treatment with alkaline mode of extraction provides an enhanced recovery percentage. Thus, the present study aimed to optimize the hydrothermal-assisted alkaline method of xylan extraction from the banana fiber biomass. Initially, xylan was extracted with a conventional-based alkali method. A maximum of about 43 and 35 % was recovered from pretreated and raw banana fiber at 12% NaOH concentration when incubated at 55 °C for 24 h. To improve the xylan yield, the hydrothermal assisted alkali method experimented in which 67.1% and 58.3 % of xylan were recovered when treated at 121 °C for 1 h at 12% NaOH. To further enhance the xylan recovery, a two-step alkali process by combining conventional and hydrothermal-assisted alkali methods resulted in the highest xylan (81%) recovery from pretreated banana fiber when incubated with 12 % alkali for 8 h followed by steam treatment. On the other hand, a maximum of 73 % of xylan was recovered when steam treated after incubation for 24 h from raw banana fiber. Thus, the alkali incubation followed by steam treatment significantly showed the highest xylan recovery from the banana fiber biomass. The extracted xylan might be utilized as a source for various xylan-based products, including furfural, xylooligosaccharides, xylose, and xylitol, all of which have significant roles in the pharmaceutical and food industries.

Sustainable biohydrogen production from lignocellulosic biomass sources - metabolic pathways, production enhancement, and challenges.

Hydrogen production from biological processes has been hailed as a promising strategy for generating sustainable energy. Fermentative hydrogen production processes such as dark and photofermentation are considered more sustainable and economical than other biological methods such as biophotolysis. However, these methods have constraints such as low hydrogen yield and conversion efficiency, so practical implementations still need to be made. The present review provides an assessment and feasibility of producing biohydrogen through dark and photofermentation techniques utilizing various lignocellulosic biomass wastes as substrates. Furthermore, this review includes information about the strategies to increase the productivity rate of biohydrogen in an eco-friendly and sustainable manner, like integration of dark and photofermentation techniques, pretreatment of biomass, genetic modification of microorganisms, and application of nanoadditives.

Evaluation of biotechnological processing through solid-state fermentation of oilseed cakes on extracts bioactive potential

Oilseed cakes (OC) are natural sources of lignocellulosic biomass, produced every year in large amounts. In addition to their main applications as animal feed, plant or soil fertilizer, and compost, they present enormous potential for being used in biotechnological processes for the obtainment and extraction of valuable bioactive compounds. This work evaluated the effect of solid-state fermentation on the bioactive properties of extracts obtained from the bioprocessing of OC and evaluated the effect of solvents on the recovery of compounds with higher bioactive potential. A general decrease of EC50 values was observed for fermented extracts obtained using a mixture of water/methanol (1:1) as extraction solvent. A decrease in the minimum inhibitory concentration was observed for fermented water extracts compared to non-fermented. Additionally, growth inhibition of Listeria monocytogenes was observed when using aqueous methanolic fermented extracts. These extracts also exhibited a higher percentage of growth reduction against phytopathogenic fungi, and some extracts exhibited increased protection against genotoxic agents such as camptothecin and bisphenol A. It was demonstrated that bioprocessing of OC through SSF is an effective approach to obtaining valuable compounds with bioactive properties for use in the food, pharmaceutical or cosmetic industries.

Hydrogen-Transfer Reductive Catalytic Fractionation of Lignocellulose: High Monomeric Yield with Switchable Selectivity.

Lignin solubilization and in situ hydrogenolysis are crucial for reductive catalytic fractionation (RCF) of lignocellulose to aromatic monomers. In this study, we reported a typical hydrogen bond acceptor of choline chloride (ChCl) to tailor the hydrogen-donating environment of the Ru/C-catalyzed hydrogen-transfer RCF of lignocellulose. The ChCl-tailored hydrogen-transfer RCF of lignocellulose was conducted under mild temperature and low-pressure (<1 bar) conditions, which was applicable to other lignocellulosic biomass sources. We obtained an approximate theoretical yield of propylphenol monomer of 59.2 wt % and selectivity of 97.3 % using an optimal content of ChCl (10 wt %) in ethylene glycol at 190 °C for 8 h. When the content of ChCl in ethylene glycol was increased to 110 wt %, the selectivity of propylphenol switched toward propylenephenol (yield of 36.2 wt % and selectivity of 87.6 %). The findings in this work provide valuable information for transforming lignin from lignocellulose into value-added products.