Bacterial cellulose (BC) possesses the desirable properties of biocompatibility, high porosity, high surface area and noticeable mechanical strength as a scaffold in bone tissue engineering. However, ...the lack of osteogenic activity restricts its application. In this study, gold nanoparticles (GNPs) with excellent osteogenic differentiation ability were incorporated into the network of BC hydrogel (Au/BC hydrogels) by the in-situ fermentation. The effects of GNPs on physicochemical properties of BC hydrogel and subsequently in vitro osteogenic differentiation and in vivo bone regeneration of Au/BC hydrogels were comprehensively investigated. The results showed that the increased feeding amounts of GNPs could remarkablly enhance the Au/BC hydrogels with better mechanical properties, higher porosity, larger surface area, and biocompatibility. The sustainable release of GNPs endowed the hydrogels with an outstanding biological activity in facilitating osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs). Mechanism research showed that autophagy might be a potential pathway for Au/BC hydrogels-induced osteogenic differentiation of hBMSCs. In addition, Au/BC hydrogel exhibited an excellent in vivo bone repair performance in a rabbit model of femoral defect, which was evidenced by the significant newly bone formation. Overall, the multifunctional Au/BC hydrogels fabricated by in-situ fermentation could serve as a good scaffold for promoting bone tissue regeneration in clinic.
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•Gold nanoparticles (GNPs) with excellent osteogenic differentiation ability were incorporated into the network of BC hydrogelby the in-situ fermentation.•The developed hydrogels demonstrated desirable mechanical properties, sustainable release ability of GNPs, favorable biocompatibility and excellent osteogenic activities.•Mechanism research revealed that autophagy might play a vital role in osteogenic differentiation of hBMSCs treated with Au/BC hydrogels.•The incorporation of GNPs into hydrogels remarkably improved the bone regeneration performance in vivo.
Lignin exhibits antioxidative and various other biological properties. However, its neuroprotection capability has rarely been studied. In this study, three types of lignin with different structures ...were prepared from grape seeds by using different isolation techniques. The antioxidative and neuroprotective effects of the lignin fractions were evaluated with the apoptosis model of murine neuroectodermal (NE-4C) neural stem cells stimulated with bisphenol AF. The results demonstrated that the half maximal inhibitory concentration for scavenging 2,2-diphenyl-1-picrylhydrazyl with water-soluble lignin (L-W, 58.19 µg·mL
−1
) was lower than those of lignin in the autohydrolyzed residue of grape seeds (84.27 µg·mL
−1
) and original lignin in grape seeds (99.44 µg·mL
−1
). BPAF exposure had negative effects on the reactive oxygen species, malondialdehyde content, and superoxide dismutase and glutathione peroxidase activities in NE-4C cells, which can be reversed by using the prepared lignin to reduce oxidative stress. An immunofluorescence assay demonstrated that grape seed lignin induced protective effects on BPAF-injured NE-4C cells via the nuclear factor erythroid 2-related Factor 2 pathway. In addition, correlational analyses showed that lignin (L-W) with lower molecular weights and noncondensed phenolic hydroxyl group content and higher contents of COOH groups effectively prevented cell apoptosis, scavenged reactive oxygen species, and ensured protection from nerve injury. This study demonstrated that grape seed lignin can be used as a neuroprotective agent and serves as a demonstration of active lignin production from grape seed waste.
Cellulose nanofibrils (CNF) is considered as an inexhaustible precursor to produce antibacterial materials, such as antibacterial hydrogel, antibacterial paper, and antibacterial film. However, the ...poor antimicrobial property of neat CNF required it should be coupled with an antibacterial ingredient. Herein, biocompatible Au nanoclusters (AuNCs) were synthesized and added into the CNF dispersion to prepare a novel antibacterial film (AuNCs@CNF film). The effects of addition of AuNCs with different amount on the morphology and physicochemical properties of AuNCs@CNF films were characterized using atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), FTIR (Fourier-transform infrared), light transmittance spectra, and thermogravimetric analysis (TGA). The results showed that AuNCs did not affect the nano-structural features of the CNF film and its basic structures, but could greatly increase the hydrophilicity, the flexibility and the thermal stability of CNF film, which might improve its application in antimicrobial wound-healing dressing. The prepared AuNCs@CNF films demonstrated high antibacterial properties toward
Escherichia coli
(
E. coli
) and
Streptococcus mutans
(
S. mutans
) both
in vitro
and
in vivo
, which can prohibit their growths and promote the healing of bacteria-infected wound, respectively. Thus, the prepared AuNCs@CNF film with great antibacterial properties could be applicable in biomedical field.
•Recombinant endoglucanase (ReEG I) was successfully produced by Pichia pastoris.•ReEG I has greater affinity for birchwood xylan than CMC.•ReEG I showed high XOS yield on birchwood xylan, up to ...69.53 ± 1.4 %.•ReEG I can produce XOS and COS concurrently on alkali-raised corncob residues.
The recombinant endoglucanase gene (EG I) from Trichoderma reesei was successfully expressed in Pichia pastoris for the purpose of producing oligosaccharides from various biomass-derived substrates. Interestingly, the recombinant endoglucanase I (ReEG I) showed the catalytic activity towards both cellulose and xylan hydrolysis, yet it was more efficient with xylans. Among various glucans and xylans substrates (paper pulp, carboxymethylated cellulose, oat spelt xylan, birchwood xylan), birchwood xylan displayed a higher yield of xylooligosaccharides (XOS) (69.5 % after optimization). Eventually, it was observed that ReEG I could simultaneously produce XOS and COS, when the alkali-extracted corncob residues were used as substrate. This is the first report on simultaneous production of XOS and COS by recombinant endoglucanase I from Trichoderma reesei expressed in Pichia pastoris, where a novel application of genetically engineered enzymes is proposed to provide an attractive application for high value utilization of biomass.
In this study, the anti-inflammatory activity of sulfated polysaccharides isolated from the green seaweed Codium fragile (CFCE-PS) was investigated in lipopolysaccharide (LPS)-stimulated RAW 264.7 ...macrophages and zebrafish. The results demonstrated that CFCE-PS significantly increased the viability of LPS-induced RAW 264.7 cells in a concentration-dependent manner. CFCE-PS remarkably and concentration-dependently reduced the levels of inflammatory molecules including prostaglandin E2, nitric oxide (NO), interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-6 in LPS-stimulated RAW 264.7 cells. In addition, in vivo test results indicated that CFCE-PS effectively reduced reactive oxygen species, cell death, and NO levels in LPS-stimulated zebrafish. Thus, these results indicate that CFCE-PS possesses in vitro and in vivo anti-inflammatory activities and suggest it is a potential ingredient in the functional food and pharmaceutical industries.
Lignin nano-particles (LNPs) exhibit properties that distinguish them from the production of other lignin-based materials. However, little research has been performed to investigate whether porous ...carbons produced from LNPs exhibit a performance superior to those derived from untreated lignin. In this study, lignin was fabricated into LNPs and used to prepare high-performance porous carbons with enhanced thermal conductivities compared to that of carbons from neat lignin. Two different preparation protocols were employed: direct pyrolysis and hydrothermal carbonization followed by pyrolysis. Carbons obtained from 100 to 300 nm LNPs possessed more graphene-like structures than carbons from unaltered lignin. In addition, carbons prepared using a combination of hydrothermal carbonization and pyrolysis exhibited higher specific surface areas (108.81–220.75 m2/g) and total pore volumes (0.098–0.166 cm3/g) than those prepared via direct pyrolysis. In addition, LNP-derived carbons exhibited superior thermal conductivities (0.45 W/mK) and thermal conductivity rates (0.51°C/s). This work provides the useful finding that superior graphene-like porous carbons can be produced by transforming lignin into LNP and then hydrothermally carbonizing the resulting material prior to pyrolysis.
Prehydrolyzate, which is from the prehydrolysis process in dissolving pulps industry, contains various sugar-derived and lignin compounds such as xylooligosaccharides (XOS), gluco-oligosaccharides, ...xylose, glucose, and soluble lignin (S-L). The XOS has several beneficial effects on human physiology. XOS and S-L in prehydrolyzate are difficult to efficiently fractionate due to their similar molecular weights and water solubility. In this work, we proposed a sustainable and green process using polystyrene divinylbenzene (PS-DVB) resin to simultaneously separate and recover XOS and S-L. Enzymatic hydrolysis with endo-1,4-β-xylanase and fermentation with
were sequentially applied to purify XOS to minimize xylose content as well as amplify contents of xylobiose and xylotriose. In addition, 2D-HSQC NMR was used to analyze the structural characteristics of XOS and S-L. Furthermore, the biological abilities of antioxidants and prebiotics of these fractions were investigated by scavenging radicals and cultivating intestinally beneficial bacterias, respectively.
Results showed that PS-DVB resin could simultaneously separate XOS and solubilized lignin with excellent yields of 93.2% and 85.3%, respectively. The obtained XOS after being purified by enzymatic hydrolysis and fermentation contained 57.7% of xylobiose and xylotriose. 10.4% amount of inherent xylan was found in the S-L fraction obtained by PS-DVB resin separation. 2D-HSQC NMR revealed that lignin carbohydrate complexes existed in both XOS and S-L as covalent linkages between lignin and 4-
-methylglucuronoarabinoxylan. The biological application results showed that the antioxidant capacity of S-L was stronger than XOS, while XOS was superior in promoting growth of intestinal
and stimulating production of short-chain fatty acids by
The proposed strategy of sequentially combining hydrophobic resin separation, enzymatic hydrolysis, and fermentation was successfully demonstrated and resulted in simultaneous production of high-quality XOS and solubilized lignin. These biomass-derived products in prehydrolyzate can be regarded as value-adding prebiotics and antioxidants.
Lignin-carbohydrate complex (LCC) is the biological macromolecule that has been demonstrated to exert multiple biological functions, including antioxidant, anti-inflammation and anti-tumorigenesis, ...which support its broad application in the bioengineering field. However, it remains elusive the involvements of LCC in human neurological disorders, especially those with the overproduction of reactive oxygen species (ROS), such as spinocerebellar ataxias (SCAs). In this study, we found a previously undetermined anti-protein aggregation activity of LCC. Initially, two individual LCC preparations and carbohydrate-free lignin were isolated from the water-extracted waste residues of
Chionanthus retusus
(
C. retusus
) tender leaves. The chemical compositional analysis revealed that lignin (61.5%) is the predominant constituent in the lignin-rich LCC (LCC-L-CR), whereas the carbohydrate-rich LCC (LCC-C-CR) is mainly composed of carbohydrate (60.9%) with the xylan as the major constituent (42.1%). The NMR structural characterization showed that LCC-L-CR preparation is enriched in benzyl ether linkage, while phenyl glycoside is the predominant type of linkage in LCC-C-CR. Both LCC and lignin preparations showed antioxidant activities as exemplified by their abilities to scavenge free radicals in cultured mammalian cells and ROS in zebrafish. We further demonstrated a pronounced capability of LCC-L-CR in inhibiting the aggregation of expanded Ataxin-3, disease protein of SCA type 3, in human neuronal cells. Taken together, our study highlights the antioxidant and novel anti-protein aggregation activities of the
C. retusus
tender leaves-derived LCC.
ABSTRACTIn recent decades, there has been a growing concern about the excessive consumption on petroleum-based sources. Scientists are now focused on increasing the utilization of natural and ...renewable sources instead of nonrenewable ones to produce safety and environmentally friendly products. Their aim is to maintain and enhance product performance while also keeping production costs in check. Within this framework, natural-fiber insulation boards emerge as a trending topic and consequently, also the use of natural adhesives to supply them and reach an entirely friendly-environment product. Natural-fiber insulation material performance is typically evaluated by its mechanical and physical properties. Among them are bending, compression, tensile strength, density, water absorption, and thermal conductivity. Throughout the cited literature, a diversity of vegetal-origin fibers, especially wood-fibers and natural adhesive sources like lignin, tannins, and proteins for insulation materials has been found, which are constantly improved in order to reach a superior production scale. This work provides a summary of research that focuses on natural fiber insulation products as well as natural adhesives, pointing to Polylactic Acid (PLA).
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