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Deep eutectic solvents (DESs) have been extensively applied to pretreat lignocellulose; however, comparative research on acidic and alkaline DES pretreatment is relatively lacking. Herein, pretreatment of grapevine agricultural by-products with seven DESs were compared in terms of removal of lignin and hemicellulose and component analysis of the pretreated residues. Among the tested DESs, both acidic choline chloride-lactic (CHCl-LA), and alkaline potassium carbonate-ethylene glycol (K 2 CO 3 -EG) were effective in delignification. Thereafter, the CHCl-LA and K 2 CO 3 -EG extracted lignin was compared by analyzing their physicochemical structure changes and antioxidant properties. The results showed that the thermal stability, molecular weight, and phenol hydroxyl percentage of CHCl-LA lignin were inferior to K 2 CO 3 -EG lignin. It was found that the high antioxidant activity of K 2 CO 3 -EG lignin was mainly attributed to the abundant phenol hydroxyl, guaiacyl (G), and para-hydroxy-phenyl (H). By comparing acidic and alkaline DES pretreatments and their lignin nuances in biorefining, novel insights are derived for the scheduling and selection of DES for lignocellulosic pretreatment. • CHCl-LA pretreatment has a great advantage in removing lignin and hemicellulose. • K 2 CO 3 -EG pretreatment benefits lignin structure and thermal stability preservation. • Significant chemical shift in the guaiacyl lignin unit of K 2 CO 3 -EG lignin. • K 2 CO 3 -EG lignin retains more phenol hydroxyl have better antioxidant properties. [ABSTRACT FROM AUTHOR]

To research the preliminary characterizations, antioxidant and hepatoprotective activity of polysaccharides from Cistanche deserticola (CDPs), three polysaccharide fractions, CDP-A, CDP-B and CDP-C, were obtained by successively membrane filtration (microfiltration, ultrafiltration and nanofiltration). Molecular weights, monosaccharide compositions, purities and IR spectra of the three fractions were analyzed. Results showed that CDP-C contained higher proportion of galacturonic acid (GalUA) than CDP-B and CDP-A. Antioxidant activities were also analyzed and the results revealed that CDP-C possessed the highest activity. Thus, hepatoprotective activity of CDP-C was studied further. In vitro research, CDP-C promoted viability of HepG2 cells. In vivo research, CDP-C ameliorated the alterations induced by alcohol, including serological indexes (alanine transaminase, acid phosphatase, γ-glutamyl transpeptidase and triglyceride) and hepatic indicators (superoxide dismutase, malondialdehyde, glutathione S-transferase and triglyceride) in model animals. The prominent microvesicular steatosis and mild necrosis in hepatic histopathology of model animals were also attenuated by CDP-C administration. These findings indicated that CDP-C possessed hepatoprotective activity against chronic hepatic injury induced by alcohol. The underlying mechanism might be that CDP-C can reduce the contents of MDA and TG, and modulate the activities of the relative enzyme. This property might associate with GalUA in CDP-C. [ABSTRACT FROM AUTHOR]

Abstract: Ultrasonic extraction (USE) of polysaccharide from cordyceps cephalosporium mycelia was introduced and compared with hot water extraction. Crude polysaccharides were investigated for morphological and thermodynamic properties. Two major fractions (USEP40-1, USEP70-1) were purified and investigated for IR spectra, molecular weights, monosaccharide compositions and antioxidant activities. The results suggested that USE gained higher extraction efficiency due to its intense extraction process. USE caused a more compact arrangement in crude polysaccharides. IR spectra of USEP40-1 and USEP70-1 were different at around 1746cm−1. The molecular weights of USEP40-1 and USEP70-1 were 61.4kDa and 25.1kDa. USEP40-1 and USEP70-1 were composed of d-mannose, d-glucose, d-galactose, l-rhamnose, and l-arabinose with molar ratio of 11.52:5.54:8.75:2.45:2.59 and 11.50:6.74:5.75:4.46:2.39, respectively. Different ABTS and hydroxyl radical scavenging activities were observed in USEP40-1 and USEP70-1. [Copyright &y& Elsevier]

Abstract: Polysaccharides from cultivated Saussurea involucrata (CSIP) were purified, two major fractions (CSIP1-2 and CSIP2-3) were investigated for their molecular weights, monosaccharide compositions and in vitro antioxidant activities. The results suggested that the molecular weights of CSIP1-2 and CSIP2-3 were approximately 163.5kDa and 88.6kDa, respectively. CSIP1-2 was composed of glucose, galactose, xylose, rhamnose, arabinose and galacturonic acid with a molar ratio of 1.651:0.39:0.062:8.331:1.759:40.426. CSIP2-3 was composed of glucose, galactose, xylose, rhamnose, arabinose and galacturonic acid with a molar ratio of 0.762:0.657:0.112:5.587:0.318:44.655. Different scavenging activities on superoxide radical, DPPH radical and hydroxyl radical were observed in CSIP1-2 and CSIP2-3 at tested concentrations. [Copyright &y& Elsevier]

Abstract: Polysaccharides were extracted from Asparagus officinalis. A novel ultrasonic circulating extraction (UCE) technology was applied for the polysaccharide extraction. Three-factor-three-level Box–Behnken design was employed to optimize ultrasonic power, extraction time and the liquid–solid ratio to obtain a high polysaccharide yield. The optimal extraction conditions were as follows: ultrasonic power was 600W, extraction time was 46min, the liquid–solid ratio was 35mL/g. Under these conditions, the experimental yield of polysaccharides was 3.134%, which was agreed closely to the predicted value. The average molecular weight of A. officinalis polysaccharide was about 6.18×104 Da. The polysaccharides were composed of glucose, fucose, arabinose, galactose and rhamnose in a ratio of 2.18:1.86:1.50:0.98:1.53. Compared with hot water extraction (HWE), UCE showed time-saving, higher yield and no influence on the structure of asparagus polysaccharides. The results indicated that ultrasonic circulating extraction technology could be an effective and advisable technique for the large scale production of plant polysaccharides. [Copyright &y& Elsevier]