Enzymatic biosynthesis of novel neobavaisoflavone glucosides via Bacillus UDP-glycosyltransferase / 中国天然药物

The present study was designed to perform structural modifications of of neobavaisoflavone (NBIF), using an in vitro enzymatic glycosylation reaction, in order to improve its water-solubility. Two novel glucosides of NBIF were obtained from an enzymatic glycosylation by UDP-glycosyltransferase. The glycosylated products were elucidated by LC-MS, HR-ESI-MS, and NMR analysis. The HPLC peaks were integrated and the concentrations in sample solutions were calculated. The MTT assay was used to detect the cytotoxic activity of compounds in cancer cell lines. Based on the spectroscopic analyses, the two novel glucosides were identified as neobavaisoflavone-4'-O-β-D-glucopyranoside (1) and neobavaisoflavone-4', 7-di-O-β-D-glucopyranoside (2). Additionally, the water-solubilities of compounds 1 and 2 were approximately 175.1- and 4 031.9-fold higher than that of the substrate, respectively. Among the test compounds, only NBIF exhibited weak cytotoxicity against four human cancer cell lines, with IC values ranging from 63.47 to 72.81 µmol·L. These results suggest that in vitro enzymatic glycosylation is a powerful approach to structural modification, improving water-solubility.

Simultaneous Determination of 7 Kinds of Components in Qing'e Pills by HPLC / 中国药房

OBJECTIVE:To develop a method for simultaneous determination of psoralen,isopsoralen,bergapten,imperato-rin,trimethylpsorale,neobavaisoflavone and bavachin in Qing'e pills. METHODS:HPLC method was adopted. The separation was performed on Kinetex-C18 column with mobile phase consisted of methanol-0.1% glacial acetic (gradient elution) at the flow rate of 1.0 mL/min. The detection wavelength was set at 248 nm. The column temperature was 30 ℃. The sample size was 20 μL. RESULTS:The linear ranges were 1.012-101.2 μg/mL for psoralen(r=0.9999),1.007-100.7 μg/mL for isopsoralen(r=0.9997), 1.010-101.0μg/mL for bergapten(r=0.9999),1.021-102.1μg/mL for imperatorin(r=0.9999),1.002-100.2μg/mL for trimethyl-psorale(r=0.9996),1.008-100.8 μg/mL for neobavaisoflavone(r=0.9999),1.025-102.5 μg/mL for bavachin(r=0.9998),re-spectively. The limits of quantitation were 0.15,0.15,0.30,0.30,0.15,0.30,0.30 μg/mL,and the limits of detection were 0.05, 0.05,0.10,0.10,0.05,0.10,0.10 μg/mL,respectively. RSDs of precision,stability and reproducibility tests were lower than 2.0%. The recoveries were 95.3%-99.6%(RSD=1.9%,n=6),96.1%-99.3%(RSD=1.2%,n=6),95.2%-98.4%(RSD=1.4%,n=6),95.4%-99.2%(RSD=1.5%,n=6),96.1%-99.3%(RSD=1.5%,n=6),95.6%-98.9%(RSD=1.4%,n=6), 95.2%-99.6%(RSD=1.6%,n=6),respectively. CONCLUSIONS:The method is simple and accurate,can be used for simultane-ous determination of 7 kinds of components in Qing'e pills.

Chemical constituents of Cremastra appendiculata and their neuroprotection / 中草药

Objective: To study the chemical constituents of Cremastra appendiculata and their neuroprotection. Methods: The chemical constituents were separated and purified by silica gel, Sephadex LH-20 column chromatography, ODS column chromatography, and HPLC column chromatography. Their structures were determined by NMR spectrum. Results: Applying various chromatographic separation methods, 23 compounds were obtained from the aceticether extraction of 55% ethanol extract of C. appendiculata. Based on physicochemical properties and spectroscopic analysis, 20 structures were identified as miltarine (1), 1-(4-β-D-glucopyranosyloxybenzyl)-2-isobutylmalate-4-methyl (2), 1-[4-(β-D-glucopyranosyloxy)benzyl]-4-methyl-2-benzylmalate (3), batatasin III-3-O-glucoside (4), eucomic acid (5), hesperidin (6), (4-methyl-1,3-phenylene) dicarbamic acid methyl ester (obtucarbamate A) (7), (3-meth-oxycarbonylamino-2-methyl-phenyl)-cabamic acid metylester (8), 4,4'-diphenylmethanebis(methyl) carbamate (9), 3,3'-dihydroxy-2',6'-bis(p-hydroxybenzyl)-5-methoxybibenzyl (10), 3',5-dihydroxy-2-(4-hydroxybenzyl)-3-methoxybibenzyl (11), 3,3'-dihydroxy-2-(4-hydroxybenzyl)-5-methoxybibenzyl (12), corylin (13), batatasin III (14), neobavaisoflavone (15), isobavachalcone (16), 2,6,2',6'-tetramethoxy-4,4-bis(2,3-epoxy-1-hydroxypropyl)biphenyl (17), coelonin (18), gigantol (19), and β-sitosterol (20). Conclusion: Compounds 7-9, 13, and 15-17 are obtained from the plants of Cremastra Lindl. for the first time. Compounds 5 and 6 are obtained from the plant for the first time. Compounds 1 and 17 have the good performance of neuroprotection in hydrogen peroxide model. Neuroprotective mechanism is likely to be achieved by weakening the oxidative damage.

Absorption mechanism of neobavaisoflavone in Caco-2 cell monolayer mode / 中国中药杂志

Neobavaisoflavone is one of flavonoids of traditional Chinese medicine Psoralea corylifolial. It has numerous biological properties such as antibacterial, anti-inflammatory, anti-cancer, and anti-osteoporosis effects. This paper aimed to investigate the absorption mechanism of neobavaisoflavone in Caco-2 cell monolayer model. The analyte and osalmide were separated on Thermo Syncronis C18 column with methanol-0.1% formic acid solution (90∶10) as the mobile phase, at a flow rate of 0.2 mL•min⁻¹. The concentration of neobavaisoflavone was determined in eletrospray ionization(ESI) positive ion mode with osalmide as an the internal standard. The effects of time, concentration, P-gp inhibitor verapamil, MRP-2 inhibitor MK-571 and BCRP inhibitor Ko143 on the absorption of neobavaisoflavone were investigated. According to the results, neobavaisoflavone showed a good linearity within the concentration of 10-2 000 μg•L⁻¹, and the results of its specificity, matrix effect, extraction recovery, precision, accuracy and stability all met the requirements. In the Caco-2 cell monolayer model, the transport volume of neobavaisoflavone was correlated positively with the time and concentration. The ER values of 15, 30, 50 μmol•L⁻¹ neobavaisoflavone were 1.64, 1.94,0.99, respectively. As compared with the control group, all of verapamil hyduochloride, MK-571 and Ko143 could promote the transportation of neobavaisoflavone, and the effect was more obvious in verapamil hyduochloride and Ko143. The absorption of neobavaisoflavone may be mainly of active transport in Caco-2 cell monolayer model, and also involve passive transport. Excretion mechanism of intestinal transport protein may be also involved.