Facile synthesis of a BCN nanofiber and its ultrafast adsorption performance.

Boron carbonitride (BCN) nanofibers with rapid and efficient adsorption performance were prepared by electrospinning technology. TEM, XRD, XPS and N2 adsorption-desorption isotherms were performed to study the microstructure of the nanofibers. The results showed that the BCN fibers synthesized at 1000 °C (BCN-1000) have good crystallinity and high specific surface areas (403 m2 g-1). BCN-1000 nanofibers adsorb 70% of amino black 10B (AB-10B) within 10 minutes and reach adsorption equilibrium within 60 minutes. Compared with previous reports, it is found that the adsorption rate of BCN-1000 nanofibers to amino black (AB-10B) is much higher than that of other adsorbents. And BCN nanofibers exhibit a large adsorption capacity (625 mg g-1). In addition, the process of AB-10B adsorption on BCN nanofibers was systematically investigated, which was in accordance with the pseudo-second-order kinetics model and Langmuir isotherm model.

[Determination of huperzine A and semi-quantitative RT-PCR analysis of lysine decarboxylase gene in different parts of Huperzia serrata from western Hunan].

OBJECTIVE: To determine the content of huperzine A in the root, stem and leaf of Huperzia serrata from western Hunan, and analyze the relationship between the distribution of huperzine A and the expression of lysine decarboxylase gene in different parts of huperzia serrata. METHODS: The content of huperzine A in the root, stem and leaf of Huperzia serrata was determinated by HPLC, of which the chromatographic column was Diamonsil C18 (250 mm x 4.6 mm,5 microm), mobile phase was methanol-0.08 mol/L CH3COONH4 with flow rate at 1.0 mL/min, column temperature at 25 degrees C and detection wavelength at 308 nm. The expression of lysine decarboxylase gene in different parts of Huperzia serrata was analyzed by semi-quantitative RT-PCR, the beta-actin gene was used as internal reference. RESULTS: Huperzine A had good linear relationships within the range of 0.5 - 10.0 microg/mL, with the recovery rate of 102% and RSD 0.32%. The content of huperzine A in the root,stem and leaf of huperzia serrata was (118.35 +/- 0.77) microg/g and (411.09 +/- 2. 47) microg/g, (562.15 +/- 2.86) microg/g, respectively. Semi-quantitative RT-PCR results showed that lysine decarboxylase gene had nearly identical expression in the root, stem and leaf of Huperzia serrate. CONCLUSION: The content of huperzine A changes with different parts of Huperzia serrata, lysine decarboxylase might be not the key enzyme to regulate the biosynthesis of huperzine A.

Characterization of Flavan-3-ols and Expression of MYB and Late Pathway Genes Involved in Proanthocyanidin Biosynthesis in Foliage of Vitis bellula.

Proanthocyanidins (PAs) are fundamental nutritional metabolites in different types of grape products consumed by human beings. Although the biosynthesis of PAs in berry of Vitis vinifera has gained intensive investigations, the understanding of PAs in other Vitis species is limited. In this study, we report PA formation and characterization of gene expression involved in PA biosynthesis in leaves of V. bellula, a wild edible grape species native to south and south-west China. Leaves are collected at five developmental stages defined by sizes ranging from 0.5 to 5 cm in length. Analyses of thin layer chromatography (TLC) and high performance liquid chromatography-photodiode array detector (HPLC-PAD) show the formation of (+)-catechin, (-)-epicatechin, (+)-gallocatechin and (-)-epigallocatechin during the entire development of leaves. Analyses of butanol-HCl boiling cleavage coupled with spectrometry measurement at 550 nm show a temporal trend of extractable PA levels, which is characterized by an increase from 0.5 cm to 1.5 cm long leaves followed by a decrease in late stages. TLC and HPLC-PAD analyses identify cyanidin, delphinidin and pelargonidin produced from the cleavage of PAs in the butanol-HCl boiling, showing that the foliage PAs of V. bellula include three different types of extension units. Four cDNAs, which encode VbANR, VbDFR, VbLAR1 and VbLAR2, respectively, are cloned from young leaves. The expression patterns of VbANR and VbLAR2 but not VbLAR1 and VbDFR follow a similar trend as the accumulation patterns of PAs. Two cDNAs encoding VbMYBPA1 and VbMYB5a, the homologs of which have been demonstrated to regulate the expression of both ANR and LAR in V. vinifera, are also cloned and their expression profiles are similar to those of VbANR and VbLAR2. In contrast, the expression profiles of MYBA1 and 2 homologs involved in anthocyanin biosynthesis are different from those of VbANR and VbLAR2. Our data show that both ANR and LAR branches are involved in PA biosynthesis in leaves of V. bellula.

An integrated approach to demonstrating the ANR pathway of proanthocyanidin biosynthesis in plants.

Proanthocyanidins (PAs) are oligomers or polymers of plant flavan-3-ols and are important to plant adaptation in extreme environmental conditions. The characterization of anthocyanidin reductase (ANR) and leucoanthocyanidin reductase (LAR) has demonstrated the different biogenesis of four stereo-configurations of flavan-3-ols. It is important to understand whether ANR and the ANR pathway widely occur in the plant kingdom. Here, we report an integrated approach to demonstrate the ANR pathway in plants. This includes different methods to extract native ANR from different tissues of eight angiosperm plants (Lotus corniculatus, Desmodium uncinatum, Medicago sativa, Hordeum vulgare, Vitis vinifera, Vitis bellula, Parthenocissus heterophylla, and Cerasus serrulata) and one fern plant (Dryopteris pycnopteroides), a general enzymatic analysis approach to demonstrate the ANR activity, high-performance liquid chromatography-based fingerprinting to demonstrate (-)-epicatechin and other flavan-3-ol molecules, and phytochemical analysis of PAs. Results demonstrate that in addition to leaves of M. sativa, tissues of other eight plants contain an active ANR pathway. Particularly, the leaves, flowers and pods of D. uncinatum, which is a model plant to study LAR and the LAR pathways, are demonstrated to express an active ANR pathway. This finding suggests that the ANR pathway involves PA biosynthesis in D. uncinatum. In addition, a sequence BLAST analysis reveals that ANR homologs have been sequenced in plants from both gymnosperms and angiosperms. These data show that the ANR pathway to PA biosynthesis occurs in both seed and seedless vascular plants.