Yong Min

Chemical Composition and Antimicrobial Activity of Marsdenia Koi Tsiang Essential Oil

The present study is the first investigation of the chemical composition and antimicrobial activitys of Marsdenia koi Tsiang essential oils. A total of forty-five compounds were identified, representing about 94.9% of the studied oil.The essential oil exhibited antibacterial activity against B.subtilis, S.aureus and S. albus with the MIC values of 50 μg/ml, 100μg/ml and 100μg/ml respectively.

Study on Chemical Constituents of Lagotis yunnanensis

Lagotis yunnanensis is a folkloric medicine in China. In order to investigate its effective components, The 95% ethanol extract of whole plant of L. yunnanensis was separated and purified with chromatographic method. Eight compounds were obtained and identified as luteolin (1), chrysoeriol (2), apigenin-7-methyl ether (3), 3, 4-dimethoxycinnamyl-D-glucopyranoside (4), verbascoside (5), cistanoside D (6), 2-O--D-glucopyranospylcucurbitacin D (7) and arvenin I (8) by spectroscopic methods. Compounds 1~3 are flavonoids, compounds 4~6 are phenylpropanoids and compounds 7 and 8 are triterpenoids. Compounds 4~8 have been obtained from this species for the first time.

A HIGHLY SELECTIVE PHOTOOXIDATION OF 2,3,5-TRIMETHYLPHENOL TO 2,3,5-TRIMETHYLBENZOQUINONE USING HYPOCRELLINS AS CATALYSTS

The photooxidation of 2,3,5-trimethylphenol by hypocrellins in organic solvent has been studied under various operating conditions for the purpose of learning more about the reactions involved and the extent of the oxidation process. This study realized nearly 100% selectivity for 2,3,5-trimethylbenzoquinone at 2.5% conversion of 2,3,5 trimethylphenol under visible light irradiation at aerobic atmosphere. The photooxidation reaction has been studied by different parameters like the effect of solvents and the influence of catalyst concentration. Compared to the conventional methods, this method could be more eco-friendly.

Degradation of Phenol by Fe3+ Doped Nano-TiO2 Photocatalyst

Degradation properties of phenol using nano-TiO2 as photocatalyst in aqueous solution were investigated. The effect of annealing temperature and ionic modification on the degradation was studied. The results showed that, 500 °C annealed TiO2 was better than 700 °C annealed. Photocatalyst nano-TiO2 material doped with Fe3+ was prepared quickly by sol-gel process and was used as photocatalyst to degrade phenol solution of 100mg/L under UV irradiation for 3 hours. UV spectrophotometer testing was made and found that two peaks at 210 nm and 270 nm were significantly become low, indicating that the phenol has been degraded. The phenol degradation rate was 94.18%.

Docking Studies on a Series of Novel Potent BRAF Inhibitors

BRAF, a serine/threonine specific protein kinase that is part of the MAPK pathway and acts as a downstream effector of RAS, is a potential therapeutic target in melanoma. We have studied a series of small-molecule BRAF inhibitors based on a 1H-imidazo[4,5-b]pyridine-2(3H)-one scaffold (ring A) as the hinge binding moiety and a number of substituted phenyl rings C that interact with the allosteric binding site. Based on molecular docking obtained by using GOLD, the interaction models on the receptor site of BRAF are guiding the design of potential inhibitory structures directed against BRAF activity.

Chemical Constituents of Boehmeria macrophylla Hornem

To investigate the chemical constituents from the Boehmeria macrophylla Hornem. the chemical constituents were isolated by various column chromatographic methods and their structures were elucidated as β-sitosterol（1）, β-sitosterol glucoside（2）, ursolic acid（3）, 7-hydroxy-6-methoxycoumarin（4）, emodin（5）, cinnamic acid（6）, sweroside（7）, Genistein（8）, all the Compounds were isolated from this plant for the first time.

Partition-Diffusion Model for Enantioseparation of Phenylalanine Using Hollow Fiber SLM

This paper deals with the partittion-diffusion model of transport and enantioseparation of phenylalanine across hollow fiber supported liquid membranes. Observed partition coefficient between the feed phase and the membrane phase, the stripping phase and the membrane phase, mass transfer resistance of boundary layer in strip phase inside the hollow fibers, boundary layer in feed phase and the diffusion in the membrane phase are taken into account in the model equations.

Comparative Research of Two Pretreatment Methods on Determination of Trace Manganese in Panax Pseudo-Ginseng Var. Notoginseng by Atomic Absorption Spectroscopy

In this research the atomic absorption spectroscopy method (the correlation coefficient was 0.9995) was employed for determination of the content of heavy metal-manganese in panax pseudo-ginseng var. notoginseng, which was chosen as the sample. The optimum conditions of two pretreatments were researched independently. In the dry ashing, the optimized temperature and time are 600°C and 4~6 hours respectively, and the manganese content determined is 53.16 ug/g and the recovery rate of manganese added in sample is 98.64%. In the wet digestion, The HNO3-H2O2 digestion system is the best one, and the content was 52.95ug/g and the recovery rate is 97.30%. So the two pretreatment methods of the sample are accurate enough on manganese content determination. But the dry ashing is better than the wet digestion relatively.

The bromination Hypocrellin A and the spectra character of the reaction of gelatin with the derivative

The bromination derivates of hypocrellin A (Br-HA) was prepared in this paper, and the photodynamic activity also was appraised. UV-Vis spectroscopy and Fluorescence spectrophotometer were employed to detect the reaction of Br-HA with gelatin. The result shown the Br-HA can react with gelatin, and the HA-Br also photodegraded the pyridinoline cross-link formation in gelatin.

Chemical Composition and Antimicrobial Activity of Volatile Components from Wild Illicium Wardii in China

The chemical composition and the antimicrobial activity of the essential oil from Illicium wardii A. C. Smith seed were evaluated.The oil which was analyzed by GC and GC/MS was found to contain limonene (18.8%), dihydrocarveol(16.6%),menthatriene(4.6%),caryophylleneoxide(3.9%),β- pinene (3.6%) as major components . Illicium wardii oil displayed a high inhibitory activity against B.subtilis and S.aureus.