Wenping Lv

Soy protein adhesives improved by SiO2 nanoparticles for plywoods

Purpose – Soy protein has been considered as a renewable and environmentally friendly source of adhesives. The purpose of this paper is to investigate a new approach for making a soy protein adhesive modified by SiO2 nanoparticles.Design/methodology/approach – The objective of this investigation was to evaluate the adhesive properties by determining the viscosity, wettability and shear strength of soy protein adhesive. The effects of nano‐SiO2 content, wood surface roughness and processing pressure on shear strength between soy protein adhesive and wood were investigated. Four nano‐SiO2 contents (0, 0.5, 1 and 2 percent), two wood surface roughness (40 and 280 grits), and two processing pressure (1 and 2 MPa) were tested. Adhesive performance was evaluated based on the maximum force required for shearing the adhesive bond between cherry wood pieces.Findings – The modified soy protein adhesives by SiO2 nanoparticles showed a significant enhancement in dry strength with nano‐SiO2 content of 1 percent. The m...

Ionic liquid-based ultrasonic/microwave-assisted extraction combined with UPLC–MS–MS for the determination of tannins in Galla chinensis

Ionic liquid was used as extraction solvents and applied to the extraction of tannins from Galla chinensis in the simultaneous ultrasonic- and microwave-assisted extraction (UMAE) technique. Several parameters of UMAE were optimised, and the results were compared with of the conventional extraction techniques. Under optimal conditions, the content of tannins was 630.2 ± 12.1 mg g−1. Compared with the conventional heat-reflux extraction, maceration extraction, regular ultrasound- and microwave-assisted extraction, the proposed approach exhibited higher efficiency (11.7–22.0% enhanced) and shorter extraction time (from 6 h to 1 min). The tannins were then identified by ultraperformance liquid chromatography tandem mass spectrometry. This study suggests that ionic liquid-based UMAE is an efficient, rapid, simple and green sample preparation technique.

An UPLC-MS-based metabolomics investigation on the anti-fatigue effect of salidroside in mice

An ultra-performance liquid chromatography-quadrupole time-of-flight-based metabolomic approach was developed to study influence of salidroside, an anti-fatigue ingredient from Rhoiola rosea, on urinary metabolic profiling of rats to a single dose of 180 mg/kg per day. Unsupervised principal component analysis (PCA) and supervised orthogonal pre-projection to latent structures discriminate analysis (OPLS-DA) on metabolite profiling revealed obvious differentiation between the salidroside treated groups and controls in both positive and negative ion modes. Eleven urinary metabolites contributing to the differentiation were identified as anti-fatigue biomarkers: N-acetylserotonin, 2-Methoxyestrone 3-glucuronide, Taurine, Melatonin, Sorbitol, Geranyl diphosphate, Z-nucleotide, Cortisone, Dihydrocortisol, Sebacic acid, Pregnenolone sulfate. The physiological significance of these biomarkers is discussed. The work showed that metabolomics is a powerful tool in studying the anti-fatigue effects of natural compound salidroside on multiple targets in vivo.

Application and recovery of ionic liquids in the preparative separation of four flavonoids from Rhodiola rosea by on-line three-dimensional liquid chromatography.

A novel on-line three-dimensional liquid chromatography method was developed to separate four main flavonoids from Rhodiola rosea. Ethyl acetate/0.5 mol/L ionic liquid 1-butyl-3-methylimidazolium chloride aqueous solution was selected as the solvent system. In the first-dimension separation, the target flavonoids were entrapped and subsequently desorbed into the second-dimension high-speed countercurrent chromatographic column for separation. In the third-dimension chromatography, the residual ionic liquid in the four separated flavonoids was removed and the used ionic liquid was recovered. As a result, 35.1 mg of compound 1, 20.4 mg of compound 2, 8.5 mg of compound 3, and 10.6 mg of compound 4 were obtained from 1.53 g R. rosea extract. They were identified as rhodiosin, rhodionin, herbacetin, and kaempferol, respectively. The recovery of ionic liquid reached 99.1% of the initial amount. The results showed that this method is a powerful technology for the separation of R. rosea flavonoids and that the ionic-liquid-based solvent system has advantages over traditional solvent systems in renewable and environmentally friendly properties.

Protective effects of polysaccharide from Dendrobium nobile against ethanol-induced gastric damage in rats

Dendrobium nobile is a medicinal herb in traditional China and Southeast Asian countries. Employing a rat model of ethanol-induced gastric ulcer, we examined the protective effect of polysaccharide (JCP) extracted from Dendrobium nobile and explored the related mechanisms. Oral administration with 100mg/kg and 300mg/kg body weight JCP for days can significant prevent the formation of gastric ulcer. Moreover, JCP pretreatment could alleviate ethanol-induced histological damage, antioxidant activities, the level of epidermal growth factor, gastric concentration of prostaglandin E, and regulate the signaling pathways of mitogen-activated protein kinases and matrix metalloproteinases. This study investigated the ethanol-induced gastric ulcer protective effect of JCP for the first time, and elucidated that the protective mechanisms.