Structural characterization and biological activities of two α-glucans from <Emphasis Type="Italic">Radix Paeoniae Alba</Emphasis>

Radix Paeoniae Alba is widely used in Chinese traditional medicine to treat various diseases such as gastrointestinal disorders, cancer, and other diseases. In this study, two polysaccharides RPAPW1 and RPAPW2 were isolated from Radix Paeoniae Alba by DEAE-52 cellulose chromatography and G-25 sephadex. According to physicochemical methods, NMR and methylation analysis, RPAPW1 and RPAPW2 were established to be α-glucans consisting of predominant 4-linked α- Glc residues branched at O-6 and contained trace amount of protein and uronic acid. Immunological tests indicated that RPAPW1, RPAPW2 and could promote splenocyte proliferation and RAW264.7 phagocytic activity. In vitro, RPAPW1 and RPAPW2 elicited a week reducing power, DPPH scavenging activity and could not protect the PC12 cells from H₂O₂ damage. These data implied polysaccharides RPAPW1 and RPAPW2 had the potential to be a natural immunopotentiating and antioxidant supplement for preparing functional foods and nutraceuticals.     

Ecophysiological responses of Cunninghamia lanceolata to nongrowing-season warming,nitrogen deposition,and their combination

Warming winter and atmospheric nitrogen (N) deposition are expected to have effects on net primary production (NPP) of Chinese fir (Cunninghamia lanceolata) plantation and implications for plantation carbon sequestration. The effects of nongrowing-season warming on plant morphological and physiological traits were investigated in a greenhouse experiment with two-year-old C. lanceolata seedlings. Elevated temperature (ET) during the nongrowing season significantly increased the net photosynthetic characteristics. The strongest effects occurred during warming period from 1 December 2014 to 1 February 2015 (W1). Moreover, the carbohydrate concentration was elevated due to the warming during W1, but it declined during four months of the warming (from 1 December 2014 to 1 April 2015, W2). The seedlings kept under N deposition (CN) showed a positive effect in all the above-mentioned parameters except δ¹³C. Significant interactions between ET and N deposition were observed in most parameters tested. At the end of the experiment (W2), the seedlings exposed to a combined ET and N deposition treatment exhibited the highest carbon contents. Our results showed that N deposition might ameliorate the negative effects of the winter warming on the carbon content.     

Length–weight relationships of two fish species from Yalong River,southwestern China

Length–weight relationships (LWRs) were evaluated for Jinshaia sinensis (Sauvage & Dabry de Thiersant, 1874) and Lepturichthys fimbriata (Günther, 1888) using a total of 289 specimens caught by gill nets (mesh size 5.0 cm) and angling in the Yalong River, southwestern China during February and March 2007. This study presents the first reference on LWR for these species from the Yalong River.     

Length–weight relationships of three fish species from the Yangtze River,China

Length–weight relationships (LWRs) were determined for three endemic fish species [Gobiobotia filifer (Garman, 1912), Homatula potanini (Günther, 1896) and Xenophysogobio boulengeri (Tchang, 1929)] from the Yangtze River in China. Samples were obtained between April 2008 and June 2012 using various types of fishing gear and electroshock fishing techniques. For each species, the sample size, length range, weight range, LWR, 95% confidence intervals of a and b, and coefficient of correlation were determined. Prior to this study, the LWRs for two species [Gobiobotia filifer (Garman, 1912) and Homatula potanini (Günther, 1896)] were unknown.