Phenolic Components from Roots of Psidium guajava / 中国实验方剂学杂志

Objective:The different parts of Psidium guajava(Myrrhinaceae) have different bioactivities. There are intensive studies for chemical constituents of its leaves and fruits at present. However,there are a few studies for the roots. Therefore, we systematically investigated the chemical constituents of phenolic acids in roots of P.guajava. Method:The chemical constituents were isolated and purified by various column chromatography methods and semi-preparative HPLC. The isolated compounds were identified by physicochemical properties and spectral analysis. Result:Sixteen phenolic components were isolated from the ethanol extract and identified as 3,3',4'-tri-O-methylellagic acid(1),3,3',4-tri-O-methylellagic acid-4'-O-β-D-glucopyranoside(2),3-O-methylellagic acid-4'-O-α-L-rhamnopyranoside(3),3'-O-methyl-3,4-O,O-metheneellagic acid-4'-O-β-D-glucopyranoside(4),gallic acid(5),methyl gallate(6),ethyl gallate(7), 3,4,5-trimethoxypheny-1-β-D-glucopyranoside(8),3,5-dimethoxy-4-hydroxy-benzoic acid-7-O-β-D-glucoside(9),1-hydroxy-3,4,5-trimethoxyphenyl-1-O-[6'-O-(4″-carboxy-1″,3″,5″-trihydroxy)phenyl]-β-D-glucopyranoside(10),vanillic acid(11),protocatechuic acid(12),secoisolariciresinol 9-O-β-D-glucopyranoside(13),phloretin 4'-O-β-D-glucopyranoside(14),cinchonain Ib(15) and epicatechin(16). Conclusion:Compounds 3,4,6,8-10,13-15 were isolated from this plant for the first time.

A new triterpenoid from roots of Psidium guajava / 药学学报

To investigated the chemical constituents of the roots of Psidium guajava,we isolated seven compounds by silica gel column chromatography.These include oleanane derivatives,2 α,3β,6β,23-tetrahydroxylurs-12,20(30)-dien-28-oic acid β-D-glucopyranoside (1),2α,3β,6β,23-tetrahydroxylurs-12,18-dien-28-oic acid β-D-glucopyranoside (2),2α,3β,23-trihydroxylurs-12,18-dien-28-oic acid β-D-glucopyranoside (3), nigaichigoside F1(4),asiaticoside C (5),2α,3β,6β,19α,23-pentahydroxylurs-12,18-dien-28-oic acid β-Dglucopyranoside (6) and 2α,3β,19α,23-tetrahydroxylurs-12-en-28-oic acid (7).Their structures were elucidated on the basis of spectral analysis with reference to the published data.Compound 1 is brand new,compounds 2-6 were first isolated from this plant.The new compound was evaluated for their cytotoxic activity against human hepatoma Bel 7402 in vitro.The results were expressed as the ratio of inhibiting Bel 7402 cells growth by comparing to untreated cells.The new compound (concentration:25 μmol·L-1) showed the ratio values of 52.5%.

Flavonoids from leaves of Psidum littorale / 药学学报

We investigated the chemical constituents of the leaves of Psidum littorale, which include 16 flavonoids, including seven flavonols, six flavonoid glycosides and three flavonones. The compounds were isolated by silica gel column chromatography. Their structures were elucidated on the basis of spectral analysis and by comparison with published data. Seven flavonols were kaempferol (1), isorhamnetin (2), myricetin-3,7,3'-trimethyl ether (3), laricitrin (4), quercetin (5), myricetin (6) and quercein-3,4'-dimethyl ether (7), six flavonoid glycosides were guaijaverin (8), hyperoside (9), 5,4'-dyhydroxy-3,7,5'-methoxyflavone-3'-O-β-D-glucoside (10), laricitrin-3-O-xyloside (11), myricetin-3-O-α-L-rhamnopyranoside (12) and myricetin-3-O-β-D-xyloside (13). Three flavonones were 4'-O-methyldihydroquercetin (14), dihydroapigenin (15) and ampelopsin 4'-O-β-D-glucopyranoside (16). Compound 10 is a new chemical, compounds 2-4, 7, 10-16 were first isolated from this plant. 1H NMR and 13C NMR data of compound 11 were not reported in literature.

Quality control of Maca (Lepidium meyenii) / 中国中药杂志

To control the quality of Maca, the quality standard was established in this study. According to the methods recorded in the Appendix of Chinese Pharmacopoeia (2010 Edition), the water, extract, total ash, acid insoluble substance, and heavy metals inspections in Lepidium meyenii were carried out. N-benzyl-9Z, 12Z-octadecadienamide in L. meyenii was identified by TLC, and it was determined by HPLC. The results showed that the N-benzyl-9Z, 12Z-octadecadienamide identification of TLC was a strong mark and specificity. In content determination experiment, the linearity of N-benzyl-9Z, 12Z-octadecadienamide was in the range of 0.01-2 microg (r = 0.9998), and the average recovery (n=9) was 99.27% (RSD 2.0%). The methods were simple, accurate, with good reproducibility. It is suitable for quality control L. meyenii.