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Agarwood is a dark resinous wood, of high quality and in a short period, can be formed after inoculation with the efficient fungus in Aquilaria sinensis. However, the action site and mechanism of the fungus inducing the agarwood formation remain unclear. In this work, the efficient fungal infection was used to induce agarwood formation on A. sinensis , and samples were collected according to inoculation time. Subsequently, the xylem structure, histochemistry, defense enzyme activities, and the accumulation and in-situ distribution of chemical composition were investigated. The transition layer (TL) was the critical layer for the continuous accumulation of agarwood, and began to appear in the injection of fungal inducers for 15 days (15D). The parenchyma cells of the xylem rays and interxylary phloem were the main action site of fungus in the formation and accumulation of agarwood. The sesquiterpenes and 2-(2-phenylethyl) chromones (PECs) were mainly accumulated in the agarwood layer (AL) and decay layer (DL), while their relative contents were highest in the injection of fungal inducers for 30 days and 180 days (30D and 180D), respectively. Among them, PECs appeared earlier than sesquiterpenes, and both were flindersia-type PECs. They were mainly concentrated in the cell corners and intercellular layer of the cell wall. In addition, Redundancy analysis (RDA) and Mantel test revealed that the different layer percentage (DLP), phenylalanine ammonia lyase (PAL), and starch grains (SG) were the drivers of PECs, and catalase (CAT) was the driver of sesquiterpenes. Therefore, this study will provide a theoretical foundation for revealing the mechanism of fungus-induced agarwood formation and inducing high-quality and high-yielding agarwood in the future. • The transition layer (TL) was the critical layer for the continuous accumulation of agarwood, and began to appear in 15D. • The parenchyma cells of the xylem rays and interxylary phloem were the action site of fungus in the agarwood formation. • The 2-(2-phenylethyl) chromones (PECs) and sesquiterpenes mainly concentrated in the cell corners and intercellular layer. • The different layer percentage, PAL and starch grains were the drivers of PECs, and CAT was the driver of sesquiterpenes. [ABSTRACT FROM AUTHOR]

The aim of this study is to apply aqueous extracts of fresh Dendrobium officinale (DOE) to modify the properties of zein, and increase synergistically the activity of curcumin (Cur). DOE was prepared using a water-extraction method firstly. Then, DOE coated-zein nanoparticles (DLZ NPs) were developed by an antisolvent precipitation method. The results showed that DOE coating improved the dispersity and stability of zein NPs greatly. At a suitable DOE content, spherical DLZ NPs with small particle size (∼200 nm) were established. They exhibited good aqueous stability and redispersibility. Then, Cur was well encapsulated (encapsulation efficiency>98%) in DLZ NPs in an amorphous state. Compared with raw Cur, Cur/DLZ NPs had more than 3.0-fold bioaccessibility, 6.8-fold antioxidant activity and higher antitumor activity, where DOE coating played a well synergistic role. Moreover, DOE coating increased the cellular uptake of zein NPs significantly. These findings suggest that DLZ NPs are promising vehicles for the oral delivery of hydrophobic bioactive substances. [Display omitted] • Novel dendrobium officinale extracts (DOE)-coated zein NPs were fabricated. • DOE coating improved the dispersity, stability and uptake of zein NPs greatly. • Curcumin (Cur) was well encapsulated in an amorphous state. • Encapsulated Cur has enhanced bioaccesibility, antioxidant and antitumor activity. [ABSTRACT FROM AUTHOR]

The suitable habitats of medicinal plants have changed as the result of climate change, which may affect quality of herbal medicine. However, as an important traditional herbal medicine, the Zanthoxylum nitidum (Roxb.) DC. lacks relevant research on coping with climate challenges. In this study, through field and online surveys, occurrence records and samples of Z. nitidum were gathered. The various periods' suitable habitats of Z. nitidum were predicted by using Maxent and ArcGIS software. The high performance liquid chromatography (HPLC) was used to ascertain the samples' nitidine chloride (NC) content. Chemometric methods was used to conduct hierarchical cluster analysis (HCA) and principal component analysis (PCA) on Z. nitidum samples from different suitable habitats. The results showed that the precipitation and temperature were significant factors in the distribution of Z. nitidum. The suitable habitats of current climate scenarios were predicted to be mainly distributed in south of the Yangtze River. The suitable habitats were predicted to gradually reduce southward under the four future climate scenarios. The contents of NC in suitable habitats were significantly higher than low-suitable habitats. Meanwhile, HCA and PCA showed that the Z. nitidum samples from different suitable habitats were effectively identified and evaluated based on bioactive substances. Overall, the findings of this study are useful references for the identification of suitable areas of Z. nitidum cultivation, as well as suitable habitats identification and quality evaluation of Z. nitidum resources in China. [Display omitted] • First time to evaluate and predict this species's distribution by MaxEnt model. • Suitable habitat area will to reduce southward in the future. • Precipitation and temperature are the key factors. • The quality of medicinal materials in the suitable habitat is better. • Samples from different habitats are effectively identified and evaluated. [ABSTRACT FROM AUTHOR]

The hemicellulose materials' gas barrier and mechanical property could sharply decline in high humidity. To address this drawback and extend the applications of hemicellulose in a high humidity environment, montmorillonite (MMT) and alkyl ketene dimer (AKD) were employed as functional agents to lower the gas permeability and improve the hydrophobicity of the hemicellulose-based film. The result showed that the water vapor permeability of the hemicellulose-based film decreased by 81.7% with the addition of MMT and the contact angle of the hemicellulose-based film increased by 131.9% after AKD modification. Meanwhile, the synergistic effect of cellulose nanofibers (CNF) and MMT can significantly improve the mechanical strength and water vapor barrier performance of the hemicellulose-based films. Moreover, the complex film exhibited a better preservation effect on the fresh green asparagus in a high humidity environment (86% RH) at room temperature, significantly reducing the weight loss of green asparagus and delaying the loss of nutrients such as Vitamin C (VC), soluble protein, and other nutrients. These green hemicellulose-based films have great food preservation potential under high humidity. [Display omitted] • MMT was added in HC film to lower the gas permeability. • AKD was employed as a functional agent to improve the HC film's hydrophobicity. • The green HC-based film has great food preservation capacity in high humidity. • Green asparagus preservation was prolonged after coating HC-based film. [ABSTRACT FROM AUTHOR]

Herein, a novel microwave-assisted alkali extraction process was proposed for further high-efficiency extraction of hemicellulose from hemp stalk. The hemicellulose extraction yield of the peeled hemp stalk surpasses 60% under mild conditions (4% alkali content, 80 °C, 30 min). Meanwhile, the hemicellulose presented a high weight-average and number-average molecular weight of 25331, 6067 g/mol. The improved efficiency could be thanks to the looser structure created by microwave expansion pretreatment via breaking the intricate structure and shielding of the hemp stalk cell wall, detailed as the specific surface area, total pore volume, and average pore size of the hemp stalk increased from 1.30 m²/g, 0.003 cm3/g, 10.66 nm to 1.85 m²/g, 0.006 cm3/g and 13.08 nm after the microwave expansion pretreatment. Furthermore, the higher expansion rate (36.74%) and water retention value (265%) of the hemp stalk also demonstrated the effective disrupting effect on the fiber structure. Finally, the empirical mass transfer model of extraction hemicellulose from hemp stalk was established. The predicted value and the experimental data showed a good correlation (R2 = 0.9998) and the model displayed excellent stability (relative deviation within 5%). Therefore, microwave-assisted alkali extraction has great potential application in the hemicellulose separation industry. [Display omitted] • Novel microwave-assisted alkali extraction for hemp stalk hemicellulose extraction. • Microwave expansion pretreatment break the complex cell structure of hemp stalk. • High-yield (surpassed 60%) and molecular weight (25331 g/mol) hemicellulose extracted. • Mass transfer model provides a guide for fine regulation hemicellulose dissolution. [ABSTRACT FROM AUTHOR]

Double-network reinforcement strategy has been widely used to improve hydrogels' toughness but is rarely applied in bulk polymer. The key to this strategy is introducing sacrificial bonds to improve strength and maintain the integrity of the polymer matrix at high elongation, dissipating applied energy as much as possible. In this study, a micron-sized microgel was employed as a sacrificial agent to reinforce polymer matrix. A simple and versatile process was introduced for the fabrication of cellulose microgel/ poly(butyl acrylate(BA)- co -methyl methacrylate(MMA)) nanocomposites by in situ free-radical polymerizations of BA and MMA complex monomer solution contained with well-dispersed cellulose microgels. After polymerization, the microgels were found homogeneously distributed within the polymer matrix. The organic-phase bacterial cellulose microgels (OB-microgel) reinforced polymer exhibited marvelous performance in the tensile test. The ultimate strength, Young's modulus, and toughness of P(BA-co-MMA) reinforced with 1.0 wt% OB-microgel were 1.13 MPa, 1.09 MPa, and 1.11 KJ m−3, about 2–3 times higher than neat P(BA-co-MMA) respectively. Moreover, a high strain to failure similar to the neat P(BA-co-MMA) was maintained. This reinforcement was mainly attributed to the sacrificing effect of microgel, not the formation of a percolation network, which was also supported by DMA test. Hence, cellulose microgel consisting of cellulose nanofiber network was demonstrated to be an efficient energy dissipation agent for the continuous phase of the polymer matrix to acquire high strain to failure and high tensile strength. [Display omitted] • A micron-sized microgel was employed as a sacrificial agent to reinforce the bulk polymer matrix. • The reinforcement effect of microgel is much better than NFC. • This reinforcement was mainly attributed to the sacrificing effect of microgel. [ABSTRACT FROM AUTHOR]