Publications (4)5.93 Total impact
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Article: Photo-activated DNA binding and antimicrobial activities of alkaloids from Glycosmis pentaphylla.
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ABSTRACT: In our screening for photosensitizers from natural resources, four alkaloids were isolated from Glycosmis pentaphylla by various chromatography techniques. Their structures were identified as glycoborinine (1), glybomine B (2), carbalexin A (3) and N-p-coumaroyltyramine (4) by spectral analysis. Their photoactivated antimicrobial activities were evaluated by thin-layer chromatography (TLC) agar overlay assay against Staphylococcus aureus and Bacillus subtilis. It was found that compounds 1 and 4 showed photo-activated antimicrobial activities. Meantime, photo-activated DNA binding activities of these compounds were also assessed by using a specially prepared 1.8 kb DNA fragment and restriction enzymes. Under UVA irradiation, compound 1 showed moderate inhibition on Nde I, Xba I, Nco I and Bcl I which have either 5'-TpA or 5'-ApT and trace or no inhibition on other restriction enzymes. It showed a similar inhibition pattern with the reference 8-methoxypsoralen. However, compounds 2-4 showed no inhibition against any of the restriction enzymes.Yao xue xue bao = Acta pharmaceutica Sinica 12/2012; 47(12):1646-52. -
Article: Chemical constituents with free-radical-scavenging activities from the stem of Fissistigma polyanthum.
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ABSTRACT: Fissistigma polyanthum is a liane belonging to the Annonaceae family and it is one of the most important crude drugs in traditional Chinese medicine. The objective was to describe the structural elucidation and the free-radical-scavenging activities of the isolated compounds from Fissistigma polyanthum. The chemical constituents were isolated and purified by normal, reverse column chromatography and HPLC. Their structures were identified by spectroscopic methods ((1)H NMR and (13)C NMR) and by comparison with literature values, and the free-radical-scavenging activities of these two compounds were also evaluated through three in vitro model systems (DPPH, trolox equivalent antioxidant capacity (TEAC) and Co (II) EDTA-induced luminol chemiluminescence by flow injection). Two known compounds, named kanakugiol (1) and teutenone A (2), were isolated from the stem of Fissistigma polyanthum for the first time, and compound 1 exhibited moderate free-radical-scavenging activity. Fissistigma polyanthum, which has traditionally been used as an important Chinese medicine, showed a certain free-radical-scavenging activity.Pharmacognosy Magazine 04/2012; 8(30):98-102. · 1.16 Impact Factor -
Article: Chemical constituents with free-radical-scavenging activities from the stem of Microcos paniculata.
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ABSTRACT: The free-radical-scavenging activities of various solvent extracts of Microcos paniculata were evaluated through in vitro model systems, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) and Co (II) EDTA-induced luminol chemiluminescence by flow injection. In all three of these systems the ethyl acetate (EtOAc) extract showed the highest free-radical-scavenging activity compared with the other three (n-BuOH, water and petroleum ether) extracts. Free-radical-scavenging assay-guided chromatographic separation of the EtOAc extract, using a normal-phase and reverse-phase silica gel column chromatography yielded five compounds: a new triterpene named methyl 3beta-O-p-hydroxy-E-cinnamoyloxy-2alpha,23-dihydroxyolean-12-en-28-oate (1), whose spectral data are presented for the first time, together with four known compounds, epicatechin (2), 3-trans-feruloyl maslinic acid (3), maslinic acid (4) and sucrose (5). All of the compounds were isolated from Microcos paniculata for the first time. The compounds were identified by spectroscopic methods. Among them, compound 2 displayed significant free-radical-scavenging activity which is similar to that of standard antioxidant ascorbic acid (V(C)) and therefore may be a promising natural antioxidant.Molecules 08/2010; 15(8):5547-60. · 2.39 Impact Factor -
Article: Prenylated xanthones from the bark of Garcinia xanthochymus and their 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities.
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ABSTRACT: Garcinia xanthochymus has been widely used in traditional Chinese medicine for expelling worms and removing food toxins. Bioassay-guided fractionation of an EtOAc-soluble extract of G. xanthochymus stem bark led to the isolation of six new xanthones. Their structures were elucidated by spectroscopic methods, especially 2D-NMR techniques. Free-radical-scavenging activities of the isolated compounds were elucidated through DPPH method. Most of the isolated compounds showed considerable free radical scavenging activity on DPPH assay. Compound 1 exhibited effective antioxidant scavenging activity against DPPH radical with an IC₅₀ value of 19.64 μM, and compound 6 showed the lowest activity among all the tested molecules, with an IC₅₀ value of 66.88 μM. These findings support the notion that the plant genus Garcinia is a good source of bioactive compounds.Molecules 01/2010; 15(10):7438-49. · 2.39 Impact Factor
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Institutions
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2010–2012
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South-Central University For Nationalities
Wuhan, Hubei, China
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