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[Display omitted] • A mild biphasic pretreatment was desirable for high efficiency fractionation. • High removal of hemicellulose and lignin were achieved. • 85.60% of cellulose was retained with 94.27% of saccharification. • 106.17 mg/g of xylonic acid was obtained by oxidation of xylose in aqueous phase. • Lignin-based film in organic phase was fabricated with good mechanical properties. Developing an efficient and facile pretreatment is of great importance to comprehensive utilization of lignocellulosic biomass. Herein, a biphasic system of 2-phenoxylethanol (EPH) and silicotungstic acid (STA) was employed for fractionation of corn stover. The EPH/STA biphasic system demonstrated remarkable fractionation efficiency to remove 90.23 % of xylan and 88.54 % of lignin, while retaining 85.60 % of cellulose under the mild pretreatment conditions of 130 °C for 90 min with 7/3 of EPH/STA and 40 mM of STA. The xylose of 52.93 % and lignin of 88.01 % were recovered in aqueous phase and organic phase by EPH/STA biphasic pretreatment, respectively. In the further process, 94.27 % of saccharification was achieved by enzymatic hydrolysis of cellulose-rich solid residue, and 106.17 mg/g of xylonic acid was obtained by oxidation of xylose in aqueous phase. Additionally, the recovered lignin in organic phase could be fabricated to lignin-based films with good mechanical properties. Notably, acid solvent in biphasic system had an important role in fractionation efficiency of corn stover. The STA had the best effect among the different acid solvents. This work provided a promising route to full components utilization of corn stover for biomass valorization. [ABSTRACT FROM AUTHOR]

The effectiveness of two drying agents, namely whey protein isolate (WPI) and maltodextrin (MD), was evaluated during spray-drying of strawberry puree. With the increase of WPI substitution in the feed material, the surface tension of strawberry puree decreased, and powder recovery increased. Powder recovery (Rp) increased from 39.2 ± 2.3% (S:MD:WPI = 60:40:0) to 56.5 ± 2.8% when MD was replaced by WPI (S:MD:WPI = 60:39:1). Surface morphology of powders showed that the addition of WPI resulted in shrunken particle surface, which gave rise to smaller DB and particle size. The particles were not spherical, and even with the addition of 0.5% WPI, the particle morphology was altered. The surface shrinkage of strawberry powder increased with increase in WPI from 0.5% to 10%. The production efficiency of strawberry powder could be greatly improved when MD was replaced by 1% WPI. [ABSTRACT FROM AUTHOR]

We have examined the influence of four phosphorus (P) levels on growth performance, photosynthetic efficiency and bioactive phytochemical production ofPrunella vulgarisL. in hydroponic culture. Results that 0.20 mM P was enhanced the dry weight, shoot height, spica and root weights, spica length and number, total chlorophyll and carotenoid contents, net photosynthetic rate, transpiration rate, and stomatal conductance were determined after three months' treatment. A supply of surplus P resulted in a higher concentration of foliar P and was negatively correlated with biomass. Both P-deficient (0 mM) and high P (10.00 mM) resulted in increased concentrations of ursolic acid and oleanolic acid, with the exception of flavonoids. An increase in water extract fromP. vulgarisspicas was noted with the application of increasing P concentrations. Our results indicated that the application of 0.20 mM P improves the biomass production and the yield of bioactive constituents ofP. vulgaris. [ABSTRACT FROM AUTHOR]

The role of hydrogen bonding (H-bonding) in polymer nucleation and crystallization is not yet so clear. To understand this physical issue, a series of poly (L-lactide) (PLLA) with different amount of terminal oxamide segments (OXA, -NHCOCONH-) were tailor-made as model H-bonding polymers (PLLA nOXA , n is the number of –NHCO–), and then the influence of H-bonding on the polymer nucleation and crystallization were investigated by a combination of experiments and molecular dynamics (MD) simulations. Compared with PLLA, much more types of H-bonds are created between the OXA segments and either the PLLA chains or the other OXA segments in the PLLA nOXA systems. A segment can be immobilized in the melt by H-bonding induced topological constraint and/or steric hindrance leading to a certain extent of reduction in entropy. Thus, the pair of H-bonded segments acting as a precursor of the "first stems" is expected to inducing local ordered structures (LOS) at elevated temperatures, which further facilitates the formation of both primary and secondary nuclei. As a consequence, the nOXA segments induced H-bonds not only significantly enhanced the crystallization temperature (T c , from 100 °C to 112 °C) and the crystallinity (X c , from 10% to 52%) of PLLA, but also increases the crystal growth rate (G) by nearly 10 times (from 0.25 to 2.66 μm min−1 at 150 °C). Moreover, a HI-MS (H-bond induced multi-stage) nucleation phenomenon in the melt of the PLLA nOXA was revealed by in-situ small-angle X-ray scattering (SAXS) under both non-isothermal (1 °C/min) and isothermal (135 °C) conditions. The HI-MS nucleation mechanism is well correlated to the nOXA induced multi-types of H-bonds which possess different thermodynamical stability at a certain high temperature. Therefore, this work not only provides a new route to make rapid crystallizing PLLA via hybridizing H-bonding segments, but also provides a molecular-level insight in the H-bonding assisted nucleation of semi-crystalline polymers in general. PLLA with H-bonding segments (OXA) were tailor-made. The H-bonds create ample immobilized segmental pairs at high (er) temperatures and improves their topological conformation which promote the nucleation of PLLA chains via a formation of stable local ordered structures. Consequently, the minor modification of PLLA not only results in nucleation at much higher temperature but increases the spherulitic growth rate as well, ascribing to an H-bonding assistanted nucleation mechanism. [Display omitted] • The terminal H-bonding were designed and introduced into the backbone of the PLLA. • The H-bonds strongly enhanced the crystallization temperature and crystallinity of the PLLA. • A H-bonds assisted nucleation mechanism is revealed in the PLLA nOXA system. [ABSTRACT FROM AUTHOR]

Prunella vulgaris L. is an important medicinal plant with a variety of pharmacological activities, but limited information is available about its response to potassium chloride (KCl) supplementation. P. vulgaris seedlings were cultured in media with four different KCl levels (0, 1.00, 6.00 and 40.00 mM). Characteristics relating to the growth, foliar potassium, water and chlorophyll content, photosynthesis, transpiration, nitrogen metabolism, bioactive constituent concentrations and yield were determined after three months. The appropriate KCl concentration was 6.00 mM to result in the highest values for dry weight, shoot height, spica and root weight, spica length and number in P. vulgaris. The optimum KCl concentration resulted in a maximum net photosynthetic rate (Pn) that could be associated with the highest chlorophyll content and fully open stomata conductance. A supply of surplus KCl resulted in a higher concentration of foliar potassium and negatively correlated with the biomass. Plants that were treated with the appropriate KCl level showed a greater capacity for nitrate assimilation. The Pn was significantly and positively correlated with nitrate reductase (NR) and glutamine synthetase (GS) activities and was positively correlated with leaf-soluble protein and free amino acid (FAA) contents. Both KCl starvation (0 mM) and high KCl (40.00 mM) led to water loss through a high transpiration rate and low water absorption, respectively, and resulted in increased concentrations of ursolic acid (UA), oleanolic acid (OA) and flavonoids, with the exception of rosmarinic acid (RA). Moreover, the optimum concentration of KCl significantly increased the yields of RA, UA, OA and flavonoids. Our findings suggested that significantly higher plant biomass; chlorophyll content; Pn; stronger nitrogen anabolism; lower RA, UA, OA and flavonoid accumulation; and greater RA, UA, OA and flavonoid yields in P. vulgaris could be expected in the presence of the appropriate KCl concentration (6.00 mM). [ABSTRACT FROM AUTHOR]

The poor mechanical properties induced by unsatisfactory crystallization ability limit the widespread use of biosynthesized poly (3-hydroxybutyrate- co -3-hydroxyhexanate) (PHBH). In this work, poly (3-hydroxybutyrate) (PHB) with a high melting point was first used as a homogeneous nucleating agent to increase the crystallization rate of PHBH by a self-nucleation method with a wider processing temperature window and crystallization kinetics and storage stability of mechanical properties of the PHBH/PHB mixtures were systematically investigated. By controlling the processing temperature and PHB content, the crystal nucleus density and crystallization rate of PHBH could be greatly increased while secondary crystallization was inhibited. When the processing temperature is 185 °C and PHB content is 20 wt%, the half crystallization time is shortened by 96% and the crystallinity was increased to 37.2%. Meanwhile, the mechanical performance of PHBH and its storage stability are greatly improved. Therefore, this work provides a simple and efficient way to improve the crystallization and mechanical performance of PHBH, which is expected to be applied to industrial production on a large scale. • PHB with a high melting point was first used as a homogeneous nucleating agent. • Crystallization rate of PHBH was greatly increased by self-nucleation. • Mechanical performance of PHBH and storage stability is improved vastly. • A simple and efficient way to improve crystallization of PHBH was provided. [ABSTRACT FROM AUTHOR]

[Display omitted] • The presence of EOs in SADF improved the WHC of oxidized MP gels. • The presence of EOs in SADF resulted in a more constrained gel structure. • In EOs, limonene and anisaldehyde played an antioxidant role. • Neither linalool nor anethole appeared to have antioxidant properties in EOs. • Anisaldehyde was capable of protecting against free radicals by demethoxylation. This study aimed to determine the efficacy of star anise dietary fiber (SADF) in alleviating the oxidative damage of myofibrillar protein (MP) from the perspective of volatile components. SADF and SADF without essential oils (EOs) (NSADF) were added to oxidized MP. The addition of NSADF and SADF improved the water-holding capacity (WHC) and gel strength, with the 0.4% addition showing the highest values. Moreover, the WHC of MP from the SADF-treated group was significantly higher than that from the NSADF-treated group at the same dosage, suggesting that EOs in SADF improved the WHC through antioxidation. EOs in SADF prevented the attack of hydroxyl radicals on MP, increasing the β-sheet level and decreasing the random coil level, which was supported by the results of FT-IR, carbonyl content, and sulfhydryl content. Limonene and anisaldehyde present in EOs played an antioxidant role, and anisaldehyde could scavenge free radicals through demethoxylation. [ABSTRACT FROM AUTHOR]

Fresh sea cucumber was processed at low temperature (60 °C and 80 °C) for different times (0 h, 1 h, 3 h, 6 h, 12 h, 24 h and 48 h). Combined with simulatior in vitro digestion and everted-rat-gut-sac model, the changes of protein in the body wall of sea cucumber (SCBWs), including oxidation rule, aggregation degree, sur- face hydrophobicity, etc, were studied. The results showed that during the whole process of heat processing, the carbonyl content increased gradually, the free sulfhydryl content decreased gradually, and the degree of protein oxi- dation showed a sequential increase. With the intensification of the degree of heat processing (underworking-moder- ate-excessive heat processing), the protein aggregation degree first decreased, then increased and then decreased, the surface hydrophobicity first increased and then decreased and then increased, and the mean protein particle size first increased and then decreased. After simulation in vitro digestion and everted-rat-gut-sac model, the degree of protein hydrolysis, in vitro digestibility and peptide transport levels were firstly increased, then decreased and then increased with the intensification of heat processing degree. In conclusion, the in vitro digestibility of SCBWs protein was the highest and the absorption characteristics were better when it was heat processed at 60 °C for 3 h. The digestion and absorption characteristics of SCBWs protein were improved when the thermal treatment time was more than 6 h at 80 °C. [ABSTRACT FROM AUTHOR]

• Shear-induced crystallization kinetics of PHA were investigated by rheometers. • Critical shear rates for the flow regime transition of PHA were determined by rheology. • Crystallization rate of PHA was greatly increased by adjusting shear conditions. • A useful theoretical guidance was obtained for shear-induced crystallization of PHA. Shear-induced crystallization plays a crucial role in the manufacturing process of polymers. In this work, crystallization kinetics of biosynthesized polyhydroxyalkanoates (PHA) under different shear conditions were systematically investigated by rheometers. First, rheological properties of PHA melts were performed at different temperature to obtain mastercurves via the time-temperature superposition principle at 170 °C as a reference temperature. Then the stretch relaxation time and corresponding critical shear rate at different temperatures for the flow regime transition were calculated via the discrete Maxwell relaxation time spectrum and Arrhenius equation. Finally, the influence of shear temperature (T s), shear time (t s) and shear rate (γ ̇) on the crystallization process of PHA were discussed. The results showed the crystallization rate of PHA was improved significantly under high shear rate and long shear time. Interestingly, the t 1/2 reached the minimum value when the γ ̇ or the t s was large enough, which reached around 450 s at isothermal crystallization condition of 100 °C. Moreover, the nucleation density for PHA increased by appx.100 times than that under quiescent conditions. Therefore, this work may provide a useful theoretical guidance on the shear-induced crystallization of PHA. [ABSTRACT FROM AUTHOR]

Multi-layer active food packing films fabricated with outer layer made of sodium alginate (SA) and inner layer made of k -carrageenan (CAR) and gelatin (GEL) contained with oregano essential oil (OEO) and ZnO nanoparticles (ZnO NPs) were developed through layer-by-layer (LBL) assemble method and characterized in this study. The results of fourier transform infrared (FT-IR) demonstrated OEO, ZnO NPs and SA outer layers were successfully incorporated into the multi-layer film system by hydrogen bonding. ZnO NPs significantly improved the mechanical properties, thermal stability, UV resistance and retention of OEO of the films (P < 0.05). Scanning electron microscope (SEM) images clearly showed SA/CAR-GEL-OEO film and SA/CAR-GEL-OEO-ZnO NPs film had a bilayer structure. Noteworthy, the multi-layer films exhibited higher OEO retention compared to the mono-layer films, and compensated the negative effect of ZnO NPs and OEO on the light transmittance while enhancing the UV resistance of the films. The multi-layer films exhibited stronger antioxidant and antibacterial activity than mono-layer films. To summarize, the multi-layer films loaded with OEO and ZnO NPs enhanced antioxidant and antibacterial activities and displayed great potential as active packaging for food preservation. [Display omitted] • Active packing film contained ZnO NPs and OEO was well fabricated by LBL assemble. • Film contained ZnO NPs and OEO showed superior antioxidant and antimicrobial ability. • ZnO NPs improved the barrier, mechanical and antimicrobial properties of film. • SA layer improved transparency, OEO retention and UV resistance of film. • SA layer combined with ZnO NPs had the best antioxidant and antimicrobial ability. [ABSTRACT FROM AUTHOR]

The renin-angiotensin system (RAS) has been recognized as a crucial contributor to the development of liver fibrosis, and AT2R, an essential component of RAS, is involved in the progression of liver fibrosis. However, the underlying mechanisms by which AT2R modulates liver fibrosis remain elusive. Here, we report that AT2R was induced to be highly expressed during the progression of liver fibrosis, and the elevated AT2R attenuates liver fibrosis by suppressing IRE1α-XBP1 pathway. In this study, we found that AT2R is not expressed in the no cirrhotic adult liver, but is induced expression during liver fibrosis in both cirrhotic patients and fibrotic mice models. Upregulated AT2R inhibits the activation and proliferation of hepatic stellate cells (HSCs). In addition, our study showed that during liver fibrosis, AT2R deletion increased the dimerization activation of IRE1α and promoted XBP1 splicing, and the spliced XBP1s could promote their transcription by binding to the AT2R promoter and repress the IRE1α-XBP1 axis, forming an AT2R-IRE1α-XBP1 negative feedback loop. Importantly, the combination treatment of an AT2R agonist and an endoplasmic reticulum stress (ER stress) alleviator significantly attenuated liver fibrosis in a mouse model of liver fibrosis. Therefore, we conclude that the AT2R-IRE1α signaling pathway can regulate the progression of liver fibrosis, and AT2R is a new potential therapeutic target for treating liver fibrosis. • AT2R inhibits hepatic stellate cell activation and proliferation through the negative feedback axis of AT2R-IRE1α-XBP1. • In vivo treatment with the agonist C21, which activates AT2R, demonstrates a reduction or even reversal of liver fibrosis progression. • AT2R may be a potential target for the treatment of liver fibrosis. [ABSTRACT FROM AUTHOR]

The application of poly(lactic acid) (PLA) is limited by its low crystallization rate. Conventional methods to increase crystallization rate usually result in a significant loss of transparency. In this work, a bundled bis-amide organic compound N′-(3-(hydrazinyloxy)benzoyl)-1-naphthohydrazide (HBNA) was used as a nucleator to prepare PLA/HBNA blends with enhanced crystallization, heat resistance and transparency. HBNA dissolves in PLA matrix at high temperature and self-assembles into bundle microcrystals by intermolecular hydrogen bonding at a lower temperature, which induces PLA to form ample spherulites and "shish-kebab-like" structure rapidly. The effects of HBNA assembling behavior and nucleation activity on the PLA properties and the corresponding mechanism are systematically investigated. As a result, the crystallization temperature of PLA increased from 90 °C to 123 °C by adding as low as 0.75 wt% of HBNA, and the half-crystallization time (t 1/2) at 135 °C decreased from 31.0 min to 1.5 min. More importantly, the PLA/HBNA maintains good transparency (transmittance > 75 % and haze is ca. 27 %) due to the decreased crystal size, even though the crystallinity of PLA is increased to 40 %, which also led to good heat resistance. The present work is expected to expand the application of PLA in packaging and other fields. [ABSTRACT FROM AUTHOR]

• GO -g- LAQ was tailor-synthesized as multifunctional fillers for bio-based PHA. • Barrier, heat resistant and antibacterial performances of PHA films are achieved. • Interfacial adhesion, condensed crystals and superior strength were generated simultaneously. • The designed PHA nanocomposites could be ideal for eco-friendly (food-)packaging. Bio-based and biocompatible materials such as polyhydroxyalkanoates (PHA) suffer from severe bacterial infection, poor oxygen barrier, low strength and poor heat resistance that restrict their wide applications especially in packaging areas. In this work, high-performance PHA nanocomposites with antibacterial properties are successfully obtained by compounding PHA with tailor-made long alkyl chain quaternary salt (LAQ) functionalized graphene oxide (GO -g- LAQ). The GO -g- LAQ could disperse in the PHA matrix uniformly and improve the interfacial adhesion between GO and PHA due to the hydrophobic nature of LAQ. As a result, PHA/GO -g- LAQ nanocomposites have the antibacterial rate of 99.9% against Gram-negative and Gram-positive bacteria without any leaching. The oxygen barrier is improved which is suggested by a significantly reduced oxygen permeation. This could be due to the condensed crystal structure of PHA and the impermeable property of GO sheets. The tensile strength and storage modulus at room temperature of the PHA films increased by 60% and 140%, respectively at an optimized concentration of GO-g-LAQ. The heat resistant performance of the PHA nanocomposites was simultaneously improved significantly due to the enhanced crystallization capability. Therefore, the well-designed PHA/GO -g- LAQ nanocomposites could be ideal candidates of functional materials for (food-) packaging applications. [ABSTRACT FROM AUTHOR]