A Chromosome-Level Genome Assembly of Dendrobium Huoshanense Using Long Reads and Hi-C Data.

Dendrobium huoshanense is used to treat various diseases in traditional Chinese medicine. Recent studies have identified active components. However, the lack of genomic data limits research on the biosynthesis and application of these therapeutic ingredients. To address this issue, we generated the first chromosome-level genome assembly and annotation of D. huoshanense. We integrated PacBio sequencing data, Illumina paired-end sequencing data, and Hi-C sequencing data to assemble a 1.285 Gb genome, with contig and scaffold N50 lengths of 598 kb and 71.79 Mb, respectively. We annotated 21,070 protein-coding genes and 0.96 Gb transposable elements, constituting 74.92% of the whole assembly. In addition, we identified 252 genes responsible for polysaccharide biosynthesis by Kyoto Encyclopedia of Genes and Genomes functional annotation. Our data provide a basis for further functional studies, particularly those focused on genes related to glycan biosynthesis and metabolism, and have implications for both conservation and medicine.

[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.

A rapid identification of four medicinal chrysanthemum varieties with near infrared spectroscopy.

BACKGROUND: For genuine medicinal material in Chinese herbs; the efficient, rapid, and precise identification is the focus and difficulty in the filed studying Chinese herbal medicines. Chrysanthemum morifolium as herbs has a long planting history in China, culturing high quality ones and different varieties. Different chrysanthemum varieties differ in quality, chemical composition, functions, and application. Therefore, chrysanthemum varieties in the market demands precise identification to provide reference for reasonable and correct application as genuine medicinal material. MATERIALS AND METHODS: A total of 244 batches of chrysanthemum samples were randomly divided into calibration set (160 batches) and prediction set (84 batches). The near infrared diffuses reflectance spectra of chrysanthemum varieties were preprocessed by first order derivative (D1) and autoscaling and was built model with partial least squares (PLS). RESULTS: In this study of four chrysanthemum varieties identification, the accuracy rates in calibration sets of Boju, Chuju, Hangju, and Gongju are respectively 100, 100, 98.65, and 96.67%; while the accuracy rates in prediction sets are 100% except for 99.1% of Hangju. CONCLUSION: The research results demonstrate that the qualitative analysis can be conducted by machine learning combined with near infrared spectroscopy (NIR), which provides a new method for rapid and noninvasive identification of chrysanthemum varieties.

[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.