[Study on Monosaccharide Compositions of Polysaccharide in Dendrobium Stems of Different Resources by PMP-HPCE].

OBJECTIVE: To establish a PMP-HPCE method for comparing the monosaccharides of polysaccharide in tissue-cultured and wild Dedrobium huoshanese and Dedrobium moniliforme as well as wild Dedrobium henanese, in order to investigate the similarities of their bioactive components. METHODS: The PMP-monosaccharides of polysaccharide from the five investigated Dedrobium samples were separated by HPCE on a fused silica capillary column(100 cm x 50 µm) at 25 °C with 350 mmol/L BAS (adjusted to pH 10 with 1.0 mol/L NaOH) as running buffer for 34 min. The applied voltage was 20 kV and the detection wavelength was set at 250 nm. RESULTS: Total six monosaccharides including xylose, glucose, mannose, galactose, galacturonic acid and ribose were detected in the five Dendrobiurms samples and the similarity coefficients between the ten batches of the same Dendrobium species were all above 0. 98,while remarkable dissimilarity were exhibited among species and different resources. CONCLUSION: PMP-HPCE technique combined with chemometrics is simple, convenient, precise, reproducible and proved to be an effective strategy for identifying the species and origins, especially in the quality assessment of Dendrobium stems.

[Prokaryotic expression of LMoV CP gene and preparation of its antiserum].

OBJECTIVE: To prepare antiserum against the CP of Lilg mottle virus (LMoV). METHODS: Specific primer was designed according to Genbank to amplify CP gene of LMoV of Fritillaria thumbergii and its sequence was analyzed. Then the CP gene was inserted into pSBET and expressed in Escherichia coli BL21 (DE3) plys E strain. The objective protein was purified by 12% SDS-PAGE firstly and subsequently 5% - 20% gradient SDS-PAGE. The antiserum against the CP was raised in mouse and their specificity was determined by Western blot. The ability to combine with nature LMoV particles was confirmed by ELISA analysis. RESULTS: LMoV CP gene shared 95% - 99% nucleotide identities and 98% - 100% amino acid identities with the CP genes reported on Genbank. The antiserum was special to LMoV CP and IgG against LMoV could combine LMoV particles. CONCLUSION: The antiserum prepared in this study is suitable for LMoV detection.