[The determination of echinacoside and acteoside in herbs of Cistanche tubulosa].

OBJECTIVE: To analyse the echinacoside and acteoside content of Cistanche tubulosa, collected from different hosts and different size of the cultivated, which is compared to the wilding by RP-HPLC method. METHOD: An Agilent Eclipse XDB-C18(4.6 mm x 250 mm, 5 microm) column was used and a mixture of methanol-acetonitrile-1% acetic acid (15:10:75) was used as the mobile phase at a flow rate of 0.6 mL x min(-1). The column temperature was 30 degrees C and the UV detection wavelength was 334 nm. RESULT: The calibration curves of echinacoside and acteoside were in good linearity over the range of 0.904-9.04 microg (r = 0.999 9), and 1.27-12.7 microg (r = 0.999 9) respectively and the average recoveries of echinacoside (and acteoside) were 98.9% (n = 5, RSD 1.9%), and 97.0% (n = 5, RSD 0.97%). CONCLUSION: The method is simple, quick, acurate. In all of the samples, the contents of echinacoside is markedly more than that of acteoside, the content of the two active component in the wilding is higher than that in the planting. The content of sample in the different sizes gradually increase from the big to the small, and the contents of samples collected from the different hosts vary markedly. These results are useful for the quality evaluation of medicinal materials of C. tubulosa.

Identification of quantitative trait loci affecting hemicellulose characteristics based on cell wall composition in a wild and cultivated rice species.

Cell wall hemicellulosic polysaccharides are structurally complex and diverse. Knowledge about the synthesis of cell wall hemicelluloses and their biological roles is limited. Quantitative trait loci (QTL) mapping is a helpful tool for the dissection of complex phenotypes for gene identification. In this study, we exploited the natural variation in cell wall monosaccharide levels between a common wild rice, Yuanj, and an elite indica cultivar, Teqing, and performed QTL mapping with their introgression lines (ILs). Chemical analyses conducted on the culms of Yuanj and Teqing showed that the major alterations are found in glucose and xylose levels, which are correlated with specific hemicellulosic polymers. Glycosidic linkage examination revealed that, in Yuanj, an increase in glucose content results from a higher level of mixed linkage ß-glucan (MLG), whereas a reduction in xylose content reflects a low level of xylan backbone and a varied arabinoxylan (AX) structure. Seventeen QTLs for monosaccharides have been identified through composition analysis of the culm residues of 95 core ILs. Four major QTLs affecting xylose and glucose levels are responsible for 19 and 21% of the phenotypic variance, respectively. This study provides a unique resource for the genetic dissection of rice cell wall formation and remodeling in the vegetative organs.