Custom-designed polyphenol lignin for the enhancement of poly(vinyl alcohol)-based wood adhesive.

Adhesives are used extensively in the wood industry. As resource and environmental issues become increasingly severe, the development of green and sustainable biomass-based adhesives has attracted increasing attention. In this work, a green wood adhesive is developed from poly(vinyl alcohol) and lignin with molecular designs of lignin extending beyond those in nature. The lignin undergoes extraction from corncob residue, aldehydration, and phenolisation (phenol, resorcinol, and catechol) to significantly increase the phenolic hydroxyl groups (over 7.92 mmol/g), which has the effect of enhancing the hydrogen bonding force between the adhesive and the wood, thereby greatly improving adhesive performance. Compared with pure PVA, polyphenol lignin-containing PVA showed improved adhesion strength and hydrophobicity. PVA/resorcinol-lignin has the significantly improved wood lap shear strength (6.27 MPa, 77.6 % improvement) and hydrophobicity (almost 100 % increase in wet shear strength). This research not only provides a green and high-performance alternative raw material for wood adhesives but also broadens the path for large-scale application of biomass.

Advances of Modified Lignin as Substitute to Develop Lignin-Based Phenol-Formaldehyde Resin Adhesives.

Traditionally, phenols used to prepare phenol-formaldehyde (PF) resin adhesives are obtained from phenolic compounds and various chemicals, which are extracted from petroleum-based raw materials. Lignin, a sustainable phenolic macromolecule in the cell wall of biomass with an aromatic ring and a phenolic hydroxyl group similar to those of phenol, can be an ideal substitute for phenol in PF resin adhesives. However, only a few lignin-based adhesives are produced on a large scale in industry, mainly because of the low activity of lignin. Preparing lignin-based PF resin adhesives with exceptional achievements by modifying lignin instead of phenol is an efficient method to improve the economic benefits and protect the environment. In this review, the latest progress in the preparation of PF resin adhesives via lignin modification, including chemical, physical, and biological modifications, is discussed. In addition, the advantages and disadvantages of different lignin modification methods for adhesives are compared and discussed, and future research directions for the synthesis of lignin-based PF resin adhesives are proposed.

The catalytic hydrodeoxygenation of bio-oil for upgradation from lignocellulosic biomass.

The increasing depletion of oil resources and the environmental problems caused by using much fossil energy in the rapid development of society. The bio-oil becomes a promising alternative energy source to fossil. However, bio-oil cannot be directly utilized, owing to its high proportion of oxygenated compounds with low calorific value and poor thermal stability. Catalytic hydrodeoxygenation (HDO) is one of the most effective methods for refining oxygenated compounds from bio-oil. HDO catalysts play a crucial role in the HDO reaction. This review emphasizes the description of the main processing of HDO and various catalytic systems for bio-oil, including noble/non-noble metal catalysts, porous organic polymer catalysts, and polar solvents. A discussion based on recent studies and evaluations of different catalytic materials and mechanisms is considered. Finally, the challenges and future opportunities for the development of catalytic hydrodeoxygenation for bio-oil upgradation are looked forward.

Dendritic cell-targeting polymer nanoparticle-based immunotherapy for cancer: A review.

Cancer immunity is dependent on dynamic interactions between T cells and dendritic cells (DCs). Polymer-based nanoparticles target DC receptors to improve anticancer immune responses. In this paper, DC surface receptors and their specific coupling natural ligands and antibodies are reviewed and compared. Moreover, reaction mechanisms are described, and the synergistic effects of immune adjuvants are demonstrated. Also, extracellular-targeting antigen-delivery strategies and intracellular stimulus responses are reviewed to promote the rational design of polymer delivery systems.

Lignin-Based/Polypyrrole Carbon Nanofiber Electrode With Enhanced Electrochemical Properties by Electrospun Method.

Tailoring the structure and properties of lignin is an important step toward electrochemical applications. In this study, lignin/polypyrrole (PPy) composite electrode films with microporous and mesoporous structures were designed effectively by electrostatic spinning, carbonization, and in situ polymerization methods. The lignin can not only reduce the cost of carbon fiber but also increase the specific surface area of composite films due to the removal of carbonyl and phenolic functional groups of lignin during carbonization. Besides, the compact three-dimensional (3D) conductive network structures were constructed with PPy particles densely coated on the lignin nanofibers, which was helpful to improve the conductivity and fast electron transfer during the charging and discharging processes. The synthesized lignin carbon fibers/PPy anode materials had good electrochemical performance in 1 M H2SO4 electrolyte. The results showed that, at a current density of 1 A g-1, the lignin carbon nanofibers/PPy (LCNFs/PPy) had a larger specific capacitance of 213.7 F g-1 than carbon nanofibers (CNFs), lignin carbon nanofibers (LCNFs), and lignin/PPy fiber (LPAN/PPy). In addition, the specific surface area of LCNFs/PPy reached 872.60 m2 g-1 and the average pore size decreased to 2.50 nm after being coated by PPy. Therefore, the independent non-binder and self-supporting conductive film is expected to be a promising electrode material for supercapacitors with high performance.

Senkyunolide H protects PC12 cells from OGD/R-induced injury via cAMP-PI3K/AKT signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Senkyunolide H (SNH) is a bioactive phthalide isolated from Ligusticum chuanxiong Hort rhizome and was reported to have multiple pharmacological effects. AIM OF THE STUDY: The study was performed to verify the potency of SNH protecting PC12 cells from oxygen glucose deprivation/reperfusion (OGD/R)-induced injury and to elucidate the underlying mechanisms. MATERIALS AND METHODS: OGD/R model was established in PC12 cells and the cell viability was measured by MTT assay. The cell morphology was observed using scanning electron microscope (SEM). The potential targets of SNH and related targets of OGD/R were screened, and a merged protein-protein interaction (PPI) network of SNH and OGD/R was constructed based on the network pharmacology analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) database was used for pathway analysis. Intracellular cAMP level and the protein expression levels were measured to elucidate the underlying mechanisms. RESULTS: SNH pretreatment protected PC12 cells against OGD/R-induced cell death. SNH also significantly protected the cell protrusion. A merged PPI network was constructed and the shared candidate targets significantly enriched in cAMP signaling pathway. The level of intracellular cAMP and the protein level of p-CREB, p-AKT, p-PDK1 and PKA protein were up-regulated after the treatment of SNH compared with OGD/R modeling. CONCLUSIONS: The present study indicated that SNH protected PC12 cells from OGD/R-induced injury via cAMP-PI3K/AKT signaling pathway.

Genetic Diversity, Chemical Components, and Property of Biomass Paris polyphylla var. yunnanensis.

Paris polyphylla var. yunnanensis is a kind of biomass resource, which has important medicinal and economical values with a huge market. This review article aims to summarize the recent development of biomass P. polyphylla var. yunnanensis. The genetic diversity and chemical components of biomass P. polyphylla var. yunnanensis were reviewed based on the literature. Both the genetic diversity and genetic structure of biomass P. polyphylla var. yunnanensis were compared by using molecular marker technologies. All the extraction processes, harvest time, and drying methods on the chemical components were summarized in detail. The differences of arbuscular mycorrhizal fungi on the infection rate, diosgenin content, microorganisms, enzyme activities, rhizospheric environment, and endogenous hormones were discussed. This review article is beneficial for the applications of biomass P. polyphylla var. yunnanensis as a biomass resource in the biomedical field.

Multifunctional Cellulose Nanopaper with Superior Water-Resistant, Conductive, and Antibacterial Properties Functionalized with Chitosan and Polypyrrole.

Cellulose nanopaper (CNP) has been considered as a promising material with great application potential in diverse fields. However, the hydrophilic nature of CNP significantly limits its practical application. In order to improve its water resistance, we demonstrate a facile approach to functionalize CNP by impregnating it with chitosan (CS), followed by in situ polymerization of polypyrrole (PPy). The results indicate that the obtained CNP/CS/PPy shows excellent water resistance with the wet tensile strength of up to 80 MPa, which is more than 10 times higher than that of the pure CNP. Intriguingly, new features (e.g., electrical conductivity, antibacterial activity, and so forth) are achieved at the same time. The functionalized CNP/CS/PPy shows a high conductivity of 6.5 S cm-1, which can be used for electromagnetic interference shielding applications with a high shielding performance of around 18 dB. In addition, the CNP/CS/PPy exhibits good antibacterial activity toward Staphylococcus aureus and Escherichia coli, with the bacterial reductions of 99.28 and 95.59%, respectively. Thus, this work provides a simple and versatile approach to functionalize CNP for achieving multifunctional properties.

Carboxymethylation of polysaccharide isolated from Alkaline Peroxide Mechanical Pulping (APMP) waste liquor and its bioactivity.

In recent years, the biological activity of polysaccharides and their derivatives has been widely studied. However, in addition to the natural polysaccharides directly extracted from plants and animals, there are rich polysaccharides in the pulping waste liquor that have not been fully utilized. The extracted polysaccharide from eucalyptus Alkaline Peroxide Mechanical Pulping (APMP) waste liquor was used as a raw material. For the production of carboxymethyl polysaccharide, the effects of temperature (T), the amount of alkali (NaOH) and the amount of etherifying agent (ClCH2COOH) on the degree of substitution (DS) were investigated, the optimal preparation conditions are: reaction time 2 h, temperature 75 °C, and the molar ratio of polysaccharide, NaOH and ClCH2COOH is 1:1:2, the highest DS is 1.47; FT-IR, NMR and GPC were used to characterize the structure and Molecular weight, the results show that the polysaccharide of APMP waste liquor is rich in xylan, and it was proved that the carboxymethyl substitution was successful and the positions of the substituent group were determined. The characterization and biological activity research of xylan polysaccharide (XP) and carboxymethyl xylan polysaccharide (CMXP), such as antioxidation, moisture absorption/retention, bacteriostatic action and cytotoxicity were discussed. CMXP shows better effects compared with XP.

Lignin-Based Micro- and Nanomaterials and their Composites in Biomedical Applications.

Lignin, as the most abundant aromatic renewable biopolymer in nature, has long been regarded as waste and simply discarded from the pulp and paper industry. In recent years, with many breakthroughs in lignin chemistry, pretreatment, and processing techniques, a lot of the inherent bioactivities of lignin, including antioxidant activities, antimicrobial activities, biocompatibilities, optical properties, and metal-ion chelating and redox activities, have been discovered and this has opened a new field not only for lignin-based materials but also for biomaterials. In this Review, the biological activities of lignin and drug/gene delivery and bioimaging applications of various types of lignin-based material are summarized. In addition, the challenges and limitations of lignin-based materials encountered during the development of biomedical applications are also discussed.

Inhibitory Effects of the Extracts of Juglans sigillata Green Husks on the Proliferation, Migration and Survival of KYSE150 and EC9706 Human Esophageal Cancer Cell Lines.

This study evaluated the antitumor activity of the extracts of green husks of Juglans sigillata Dode on esophageal cancer. KYSE150 EC9706 cells were treated with different concentrations of six components of the extracts of J. sigillata green husks. Cell viability was measured by MTT. Cell migration and cell invasion were measured by wound-healing assays and transwell assays, respectively. Cell apoptosis and cycle were measured by flow cytometry. The expression of cell migration, cell cycle and cell apoptosis regulatory proteins was analyzed by Western blotting. Only the three constituents, including EtOH extractives, EtOAc soluble fraction and gallic acid (GA), exhibited inhibitory effects on the cell viability, migration and invasion by decreasing MMP2 and MMP9 expression (all P < 0.05). Flow cytometry revealed that these three constituents also induced cell apoptosis by increasing Bax and cleaved caspase-3 but decreasing Bcl-2 in KYSE150 and EC9706 cells. Furthermore, these constituents arrested the cell cycle at G0/G1 by downregulating the expression of Cyclin D1 but upregulating p53 and phospho-p53 expression in KYSE150 cells. In conclusion, the green husks of J. sigillata may act as a potential inhibitor on esophageal cancer growth. GA was the major single active constituent of the extracts.

Senkyunolide H protects against MPP+-induced apoptosis via the ROS-mediated mitogen-activated protein kinase pathway in PC12 cells.

Senkyunolide H (SNH) is a phthalide isolated from the rhizome of Ligusticum chuanxiong Hort. that has been reported to have several pharmacological activities, including anti-atherosclerotic, antiproliferative, and cytoprotective effects. In this study, we investigated the neuroprotective effects and potential mechanisms of SNH against 1-methyl-4-phenylpyridinium (MPP+)-induced oxidative stress. We demonstrated that SNH pretreatment significantly attenuated MPP+-induced neurotoxicity and apoptosis in PC12 cells. In addition, SNH attenuated the effect of MPP+ on the expression of the pro-apoptotic factors Bax and caspase-3. Meanwhile, SNH prevented oxidative stress by reducing reactive oxygen species generation, mitochondrial membrane potential loss, cytochrome C release, and malondialdehyde levels while increasing antioxidant enzyme activity (e.g., superoxide dismutase, catalase, and glutathione peroxidase). In addition, SNH inhibited nuclear accumulation of nuclear factor-κB and c-Jun N-terminal kinase and phosphorylation p38 mitogen-activated protein kinases (MAPKs). Overall, this investigation provides novel evidence that SNH exerts neuroprotective effects via the ROS-mediated MAPK pathway and represents a potential preventive or therapeutic agent for neuronal disorders.

Drug-loaded poly(L-lactide)/lignin stereocomplex film for enhancing stability and sustained release of trans-resveratrol.

We report a new drug-loaded film for blending poly(L-lactide) (PLLA) with lignin-based functional filler, which enhanced stability and sustained release of trans-resveratrol (trans-RSV). In addition, trans-RSV loaded PLLA/lignin films showed good antioxidant and anticancer effects. Incorporation of the optimized amount of lignin-based filler to PLLA matrix was key to achieve these desired functions. The lignin-based filler (LG-g-PDLA) was synthesized via ring-opening polymerization on alklin lignin with D-lactide. Benifiting from the stereocomplex formation (PLLA and PDLA side chains), similar polyphenolic structures between lignin and trans-RSV, and UV chromophoric groups of lignin, trans-RSV loaded PLLA/lignin-graft-PDLA films (R/P/LGPD) have good performances on mechanical property, uniformity distribution of drug, and light barrier property. The release behaviors of trans-RSV could be controlled by variation of LG-g-PDLA content. This system therefore offers great potential for the delivery of poor water soluble and light stability drugs.

"Nano-Ginseng" for Enhanced Cytotoxicity AGAINST Cancer Cells.

Panax ginseng has high medicinal and health values. However, the various and complex components of ginseng may interact with each other, thus reducing and even reversing therapeutic effects. In this study, we designed and fabricated a novel "nano-ginseng" with definite ingredients, ginsenoside Rb1/protopanaxadiol nanoparticles (Rb1/PPD NPs), completely based on the protopanaxadiol-type extracts. The optimized nano-formulations demonstrated an appropriate size (~110 nm), high drug loading efficiency (~96.8%) and capacity (~27.9 wt %), long half-time in systemic circulation (nine-fold longer than free PPD), better antitumor effects in vitro and in vivo, higher accumulation at the tumor site and reduced damage to normal tissues. Importantly, this process of "nano-ginseng" production is a simple, scalable, green economy process.

Bioconversion of conjugated linoleic acid by Lactobacillus plantarum CGMCC8198 supplemented with Acer truncatum bunge seeds oil.

Conjugated linoleic acid (CLA) isomers, c9, t11-CLA and t10, c12-CLA, have been proved to exhibit excellent biomedical properties for potential use in anti-cancer applications and in reducing obesity. Acer truncatum Bunge (ATB), which is rich in unsaturated fatty acids, including oleic acid, linoleic acid, and nervonic acid, is a new resource for edible oil. In the present study, we developed a new method for producing two CLA isomers from ATB-seed oil by fermentation using Lactobacillus plantarum CGMCC8198 (LP8198), a novel probiotics strain. Polymerase chain reaction results showed that there was a conserved linoleate isomerase (LIase) gene in LP8198, and its transcription could be induced by ATB-seed oil. Analyses by gas chromatography-mass spectrometry showed that the concentration of c9, t11-CLA and t10, c12-CLA in ATB-seed oil could be increased by about 9- and 2.25-fold, respectively, after being fermented by LP8198.

5-Methoxyl Aesculetin Abrogates Lipopolysaccharide-Induced Inflammation by Suppressing MAPK and AP-1 Pathways in RAW 264.7 Cells.

For the first time, a pale amorphous coumarin derivative, 5-methoxyl aesculetin (MOA), was isolated from the dried bark of Fraxinus rhynchophylla Hance (Oleaceae). MOA modulates cytokine expression in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, but the precise mechanisms are still not fully understood. We determined the effects of MOA on the production of inflammatory mediators and pro-inflammatory cytokines in the LPS-induced inflammatory responses of RAW 264.7 macrophages. MOA significantly inhibited the LPS-induced production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), interleukin-6, and interleukin-1ß. It also effectively attenuated inducible nitric oxide (NO) synthase, cyclooxygenase-2, and TNF-α mRNA expression and significantly decreased the levels of intracellular reactive oxygen species. It inhibited phosphorylation of the extracellular signal-regulated kinase (ERK1/2), thus blocking nuclear translocation of activation protein (AP)-1. In a molecular docking study, MOA was shown to target the binding site of ERK via the formation of three hydrogen bonds with two residues of the kinase, which is sufficient for the inhibition of ERK. These results suggest that the anti-inflammatory effects of MOA in RAW 264.7 macrophages derive from its ability to block both the activation of mitogen-activated protein kinases (MAPKs) and one of their downstream transcription factors, activator protein-1 (AP-1). Our observations support the need for further research into MOA as a promising therapeutic agent in inflammatory diseases.

Apigenin-7-O-ß-D-glucuronide inhibits LPS-induced inflammation through the inactivation of AP-1 and MAPK signaling pathways in RAW 264.7 macrophages and protects mice against endotoxin shock.

Apigenin-7-O-ß-D-glucuronide (AG), an active flavonoid derivative isolated from the agricultural residue of Juglans sigillata fruit husks, possesses multiple pharmacological activities, including anti-oxidant, anti-complement, and aldose reductase inhibitory activities. To date, no report has identified the anti-inflammatory mechanisms of AG. This study was therefore designed to characterize the molecular mechanisms of AG on lipopolysaccharide (LPS)-induced inflammatory cytokines in RAW 264.7 cells and on endotoxin-induced shock in mice. AG suppressed the release of nitric oxide (NO), prostaglandin E2 (PGE2), and tumour necrosis factor-α (TNF-α) in LPS-stimulated RAW 264.7 macrophages in a dose-dependent manner without affecting cell viability. Additionally, AG suppressed LPS-induced mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and TNF-α. AG treatment decreased the translocation of c-Jun into the nucleus, and decreased activator protein-1 (AP-1)-mediated luciferase activity through the inhibition of both p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK) phosphorylation. Consistent with the in vitro observations, AG protected mice from LPS-induced endotoxin shock by inhibiting proinflammatory cytokine production. Taken together, these results suggest that AG may be used as a source of anti-inflammatory agents as well as a dietary complement for health promotion.

Ginsenoside nanoparticle: a new green drug delivery system.

A large amount of chemosynthetic nano-drug carrier has to be used to administer a needed dose of a drug. However, high doses of these excipients may cause the emergence of toxic potential to patients. Green chemistry aims to develop green nanoparticles loaded with drugs to reduce the use of toxic and harmful ingredients in the production process and provide lower-dose prescriptions for medical treatments. The use of non-toxic materials in pharmaceutical formulations could minimize the adverse effects of pharmaceutical residues entering the body and environment. Ginsenoside is the main bioactive constituent of the herb Panax ginseng. Here, we firstly find that ginsenoside Rb1 can self-assemble with anticancer drugs to form stable nanoparticles, which have greater anticancer effects in vitro and in vivo than the free drugs. The obtained nanoparticles possessed an appropriate size (∼100 nm), better tumor selectivity, high drug loading capacity (∼35 wt% betulinic acid, ∼32 wt% dihydroartemisinin, and ∼21 wt% hydroxycamptothecine), and a higher blood circulation half-time. Furthermore, the antitumor effect of the nanoparticles in a mouse tumor xenograft model exhibited a much better tumor inhibition efficacy and fewer side effects than those of the free drugs, strongly supporting their application as a novel efficient nanocarrier for anticancer therapy. Moreover, ginsenoside nanoparticles with a simple, green preparation method and easy large-scale production are promising for the delivery of various insoluble drugs.

A novel self-assembled targeted nanoparticle platform based on carboxymethylcellulose co-delivery of anticancer drugs.

Single-drug therapy for cancer is greatly hampered by its non-specific delivery to the target tissue, limited efficacies, poor tolerability, and resistance profiles. In order to overcome these limitations, we developed a new targeted nanoparticle platform for co-delivery of two different anticancer drugs. A conjugate based on carboxymethylcellulose (CMC) was first synthesized by introducing hydrophilic molecules (PEG), target molecules (folate), and drug molecules (betulinic acid) into CMC. Then another anticancer drug hydroxycamptothecine (HCPT) was encapsulated into the nanoparticles from the conjugate using a simple nanoprecipitation method. The obtained nanoparticles possessed appropriate size (∼180 nm), high drug loading efficiency (∼23 wt% BA, 21.15 wt% HCPT), a slow drug release rate, higher blood circulation half-time of free BA (6.4-fold) and HCPT (6.0-fold), and high synergetic activity of BA and HCPT toward cancer cells. Furthermore, the targeted nanoparticles showed rapid cellular uptake by tumor cells. The antitumor effect of the nanoparticles in a mouse tumor xenograft model exhibited a much better tumor inhibition efficacy and fewer side effects than that of BA and HCPT, strongly supporting their application as efficient carriers for anticancer therapy.

Self-assembled targeted folate-conjugated eight-arm-polyethylene glycol-betulinic acid nanoparticles for co-delivery of anticancer drugs.

In this study, a targeted nanoparticle platform for co-delivery of anticancer drugs based on folate-conjugated eight-arm-polyethylene glycol-betulinic acid (F-8arm-PEG-BA) was first presented. F-8arm-PEG-BA was synthesized by introducing target molecules (folate) and drug molecules (betulinic acid, BA) to hydrophilic molecules (8arm-PEG). Then another anticancer drug, hydroxycamptothecin (HCPT), was encapsulated into the self-assembled nanoparticles from the conjugate by a simple nanoprecipitation method. These F-8arm-PEG-BA/HCPT nanoparticles (NPs) had a small size (∼120 nm), acceptable critical aggregation concentration (∼64.8 µg mL-1), and high drug loading (∼18 wt% BA and ∼16 wt% HCPT). Compared to the free drugs, the nanoparticles significantly improved the cellular cytotoxicity and exhibited an obvious synergistic effect by the co-delivery of two different anticancer drugs, BA and HCPT. Pharmacokinetics study revealed the nanoparticles could prolong the circulation of BA and HCPT in the blood. In vivo studies indicated that the nanoparticles enhanced tumor targeting and antitumor activity with lower systemic toxicity. In conclusion, F-8arm-PEG-BA/HCPT NPs have great potential for targeted chemotherapy for cancer.