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Polylactic acid (PLA) is a promising food packaging material with biocompatible, nontoxic and biodegradable. In order to reduce the deterioration of aquatic products caused by microorganisms, PLA coaxial nanofiber films with cinnamaldehyde (CMA), tea polyphenol (TP) and its composite as core materials were prepared by using coaxial electrospinning technology. Its microscopic morphology and structure were characterized separately, and its thermal stability, wettability and mechanical properties were determined. The antibacterial activity and antibacterial mechanism of nanofiber films were studied with Shewanella putrefaciens (S. putrefaciens) which is the dominant spoilage of aquatic products as the target of action. The results show that the CMA/TP (m/m = 2:5)-PLA coaxial nanofibers have small diameter, uniform distribution, smooth surface, no pores and fracture. At the same time, the film has strong hydrophobicity, good thermal stability and mechanical properties. Its antibacterial performance is better than that of single-core nanofiber films, which effectively destroys the cell membrane of S. putrefaciens , increases the permeability of cell membrane, and interferes with the synthesis and expression of its protein. The coaxial nanofiber films with CMA, TP and its composite as core material can be used as a fresh-keeping material with antibacterial properties, and has potential application value in the field of food preservation. • CMA/TP-PLA nanofiber films with the coaxial structure and two core materials are prepared. • The addition of the core material improves the physicochemical properties of the nanofiber films. • The CMA has synergistic antibacterial effect with TP. • CMA acts on the phospholipid bilayer of the cell membrane, destroying the cell membrane. • TP destroys extracellular proteins, leading to cell membrane perforation and cell death. [ABSTRACT FROM AUTHOR]

As a synthetic pigment, Sudan red is commonly used as a food additive and is harmful to the human kidney and can even cause cancer. In this work, we developed a one-step strategy to synthesize lignin-based hydrophobic deep eutectic solvents (LHDES), which were fabricated via methyltrioctylammonium chloride (TAC) as hydrogen bond acceptor and alkali lignin as hydrogen bond donor. LHDES with different mass ratios were synthesized and the mechanism of formation was determined by different characterization techniques. The synthetic LHDES was used as the extraction solvent to establish a vortex-assisted dispersion-liquid microextraction method for the determination of Sudan red dyes. The practicality of LHDES was evaluated by applying it to the detection of Sudan Red I in real water samples (seawater, river water) and duck blood in foodstuffs, and the obtained extraction rate reached up to 98.62 %. The method is simple and effective for the determination of Sudan Red in food. [Display omitted] [ABSTRACT FROM AUTHOR]

Cyclic GMP-AMP (cGAMP) synthase (cGAS) is a predominant DNA sensor inducing the activation of the innate immune responses that produce proinflammatory cytokines and type I interferons, which has been well-investigated in mammals. However, chicken cGAS (chcGAS), which participates in avian innate immunity, has not been well-investigated. Here, we cloned the complete open reading frame sequence of chcGAS. Multiple sequence alignment and phylogenetic analysis revealed that chcGAS was homologous to mammalian cGAS. The chcGAS mRNA was highly expressed in the bone marrow and ileum. The subcellular localization of chcGAS was mainly in the cytoplasm, and partial co-localization was observed in the endoplasmic reticulum. Through overexpression and RNA interference, we demonstrated that chcGAS responded to exogenous dsDNA, HS-DNA, and poly(dA:dT), and to self dsDNA from the DNA damage response, thereby triggering the activation of STING/TBK1/IRF7-mediated innate immunity in both chicken embryonic fibroblasts and chicken liver cancer cells. Furthermore, downregulation of chcGAS enhanced the infection of fowl adenovirus serotype 4 in LMH cells. Our results demonstrated that chcGAS was an important cytosolic DNA sensor activating innate immune responses and may shed light on a strategy for preventing infectious diseases in the poultry industry. [ABSTRACT FROM AUTHOR]

In this study, an environmental-friendly hydrothermal pretreatment of Eucalyptus fiber followed with alkali post-treatment was developed to produce bioethanol efficiently. This biorefinery process allowed all major components of biomass being converted into high value-added products. The chemical and structural features of the residual hemicelluloses isolated with alkali from the hydrothermal pretreated Eucalyptus fiber, were comparatively investigated. Sugar and spectral analyses indicated that the hemicelluloses were mainly composed of glucuronoxylans, and especially hemicelluloses prepared at higher temperature (180 °C) contained higher contents of glucomannans and α-glucan. Hydrothermal pretreatment resulted in a significant hydrolysis of the glycosidic linkages in xylan backbone, and thus the molecular weight of the hemicelluloses was significantly reduced from 56,520 to 7780 g/mol with the increase of temperature. This suggested that a combination of hydrothermal pretreatment at low temperatures (100–140 °C) and alkali post-treatment was an effective technique for isolating of hemicelluloses from Eucalyptus fiber. [ABSTRACT FROM AUTHOR]

This study proposed a sustainable method to prepare cellulose I nanocrystals (CNCs I) from microcrystalline cellulose (MCC) in a mildly acidic lithium bromide trihydrate (MALBTH) system, a concentrated (50 wt%) solution of LiBr in water with recyclable formic acid (FA). First, the MCC was treated in the MALBTH system to generate CNCs with a uniform size, yield higher than 68.49% and crystallinity of 84.02%. Then, the CNCs could application for stabilizing Pickering emulsions for at least 15 days. Furthermore, FA was easily recycled from the MALBTH system, and the yield of the CNCs produced from the hydrolysis of MCC by using the recycled FA was still higher than 60%. Finally, this study provided a sustainable and green production of CNCs. A low-cost and environmentally friendly pathway to recover FA from the MALLBTH system at a high yield was still realized. [Display omitted] • Green and economical MALBTH system was developed for CNCs I. • MALBTH is an emerging process for economic production of CNCs I products. • CNCs I had higher yield, crystallinity index and smaller particle size. • The FA displayed good recyclability and stability in this system. • Pickering emulsion stabilized by CNCs I was storage stability. [ABSTRACT FROM AUTHOR]

Lignin is utilized as a carbon precursor to produce microporous lignin-derived carbon-based solid acid (MLC-S) ZnCl 2 activation and sulfonation with concentrated sulfuric acid. The effects of reaction conditions, namely the ratio of methanol to oleic acid, carbonization temperature, and catalyst dosage, on the efficiency of the esterification of oleic acid with methanol are investigated. As a carbon-based solid acid, the MLC-S offers high catalytic activity in the esterification, which is a crucial reaction in the synthesis of biodiesel. Compared with nonactivated lignin-derived carbon-based solid acid (LC-S), the highly porous structure of the MLC-S makes its active sites more accessible and ensures its excellent catalytic performance. Under the optimal conditions, the esterification of oleic acid with methanol reaches a conversion of 92.3%. Moreover, after recycling the MLC-S for five times, the extent of the esterification reaction is still as high as 72.9%. Obviously, the synthesized MLC-S has considerable potential for the esterification of oleic acid with methanol and thus for biodiesel production. Unlabelled Image [ABSTRACT FROM AUTHOR]

The gradual depletion of petroleum is a main challenge restricting the development for the fine chemicals, such as epoxy resin adhesive. In this study, a novel lignin-containing high-performance epoxy resin adhesive is synthesized using lignin as precursor material. Lignin is a unique biomacromolecule with three dimensional network structure, large molecular weight, and aromatic structure. The lignin is simply hydrolyzed and modified by epichlorohydrin to obtain lignin-based epoxy prepolymer. The hydrolysis process effectively reduces the molecular weight and improves the chemical reactivity of lignin, thus increasing the number of modified functional groups and the dispersibility of lignin concurrently. With the introduction of the lignin-based epoxy prepolymers, the shear strength of the adhesive increases obviously and reaches 10.42 MPa, which displays 228% of the shear strength of commercial epoxy resin adhesives. Furthermore, the lignin-containing epoxy resin adhesive still displays excellent mechanical properties in extreme environments, including extreme temperature and high humidity environment. [ABSTRACT FROM AUTHOR]

China, a big paper-making country, produced hundreds of millions of tons of waste paper which contain a lot of fiber every year. Cellulose nanocrystals were extracted from recycled waste paper which can be a high value utilization of secondary fiber. In this paper, cellulose nanocrystals were successfully extracted from waste paper fibers via two different systems, sulfuric acid hydrolysis (SCNCs) and one-step ammonium persulfate (APS) oxidation (OCNCs). This not only broadened the methods of extracting CNCs from waste paper, but also improved the dispersion and reactivity of CNCs. The CNCs products were investigated by FT-IR spectroscopy for functional group structure, X-ray diffraction for crystal structure, TG-DTG for thermal stability and scanning electron microscope, transmission electron microscope for morphology. The results showed that both OCNCs and SCNCs were a rod-like structure. The crystallinity of OCNCs and SCNCs increased to 72.45 and 77.56, but with a low yield of 22.42% and 41.22%, respectively. The result also suggested H 2 O 2 formed by decomposition of APS, selectively oxidized the hydroxyl on the C 6 in cellulose to carboxyl, introduced 0.57 mmol/g carboxyl. Successful preparation of CNCs extracted from waste paper can effectively utilize the fiber resources in waste paper, thus transforming into higher economic benefits. • CNCs was successfully extracted from waste paper fibers via different systems. • No ink-towing or bleaching treatment was carried out during the preparation of CNC. • The structure of CNCs prepared via different systems was compared differences completely and systematically [ABSTRACT FROM AUTHOR]