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Meng L.,South China Normal University | Yang W.,South China Normal University | Pan X.,South China Normal University | Tao M.,South China Normal University | And 5 more authors.
Journal of Organic Chemistry | Year: 2015

A platinum(II)-catalyzed asymmetric ring opening of oxabenzonorbornadienes with phenols was developed, which afforded the corresponding cis-2-(un)substituted phenoxy-1,2-dihydronaphthalen-1-ol products rather than the trans ones in excellent yields (up to 99%) with moderate to good enantioselectivities (up to 87% ee) under mild conditions. In addition, the cis-configuration of product 2b was confirmed by X-ray diffraction analysis. Based on the results, a potential mechanism for the present catalytic reaction was proposed. © 2015 American Chemical Society. Source

Guo Q.,Guangdong University of Technology | Yuan J.,Guangdong Food Industry Institute | Zeng J.,Guangdong University of Technology
Biotechnology and Biotechnological Equipment | Year: 2014

The binding mechanisms of the interaction of three dihydromyricetin (DMY)-metal complexes (DMY-Cu (II) complex, DMY-Mn (II) complex, DMY-Zn (II) complex) and DMY with bovine serum albumin (BSA) were investigated using fluorescence and ultraviolet spectroscopy at different temperatures. The results indicated some differences in the binding process between different DMY-metal complexes and BSA compared with that of free DMY. All of the complexes and DMY quenched the fluorescence of BSA based on static mode combined with radiationless energy transfer, yet having different binding distance based on the Förster theory. Different DMY-metal complexes can change the binding constants. The binding constants increase for DMY-Cu (II) and DMY-Mn (II) complexes, whereas the opposite is true for the DMY-Zn (II) complex compared to the one with free DMY. The DMY-metal complexes can also affect the types of the interaction. The van der Waals forces and hydrogen bonding may play a major role in the interaction of free DMY with BSA, while for the three complexes, the nature of the binding forces lies in hydrophobic forces and hydrogen bonding based on the thermodynamic parameters. © 2014 The Author(s). Published by Taylor & Francis. Source

Guangdong Food Industry Institute | Date: 2013-10-14

Adjuvant for use with agricultural chemicals; Alkalies; Ammoniacal salts; Anhydrous ammonia; Biochemical catalysts; Chemical fertilizers; Chemical preparations for preserving foodstuffs; Chemical preparations for preventing pathogenic infections in plants; Enzymes for use in the processing of sugar cane; Fertilizers and manures; Halides and halogen acid salts; Lactic acid; Lactose for industrial purposes; Silicon.

Wang S.-Y.,Sun Yat Sen University | Wang S.-Y.,Guangdong Food Industry Institute | Xu Z.-L.,South China Normal University | Wang H.,South China Normal University | And 6 more authors.
Helvetica Chimica Acta | Year: 2012

The novel natural product xyloallenoide A, isolated from the marine mangrove endophytic fungus from the South China Sea, and its diastereoisomer xyloallenoide A1, which contain N-methyl-substituted amino acids, were synthesized. The absolute configurations of the amino acid units of xyloallenoide A were finally confirmed to be L-Lys, Me-D-Val, and Me-L-Ala. This report represents a practical and attractive alternative for the synthesis of N-methyl-substituted cyclotripeptides. In the preliminary bioassay, synthetic xyloallenoide A showed marginal activities against KB (IC 50=9.6 mm) and KBv200 cells (IC50=10.3 μm), and xyloallenoide A1 was inactive against KB and KBv200 cells. © 2012 Verlag Helvetica Chimica Acta AG. Source

Cui B.-Q.,Guangdong Food Industry Institute
Modern Food Science and Technology | Year: 2013

For purification total alkaloids of Nelumbonucifera leaves, capability of adsorption and desorption of three kinds of macroporous adsorption resin such as AB-8, D101 and HP-20 were explored. Then the effects of adsorption parameters, such as flow rate of adsorption, pH value, maximum loading amount of the extract solution; concentration, pH value of eluant and flow rate of desorption, on the nuciferine content were investigated by HPLC. The results showed that D101 was the most efficient Resin. The optimum condition were 2BV/h of loading rate, 10 of pH value, 6 BV of maximum loading amount of the extract solution, flow rate of desorption 2BV/h and pH 3 of the eluent (70% aqueous ethanol solution). Under such conditions, the ratio of nuciferine to the purified extract of Nelumbonucifera leaves was up to 2.26%. This research provided references for comprehensive development and utilization of the total Alkaloids of Leaves of Nelumbonucifera Gaertn. Source

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