• Archives of Pharmacal Research
• /
• v.21 no.4
• /
• pp.406-410
• /
• 1998

Biflavonoid is one of unique classes of naturally-occurring bioflavonoids. Certain biflavonoids including amentoflavone were previously reported to have inhibitory effect on the group 11 phospholipase $A_2$ activity. Amentoflavone was also found to inhibit cyclooxygenase from guinea-pig epidermis without affecting lipoxygenase. In this study, anti-inflammatory and analgesic activities of amentoflavone were evaluated. When amentoflavone was administered intraperitoneally, it showed a potent anti-inflammatory activity as determined by amelioration of croton-oil induced mouse ear edema. It also showed a potent anti-inflammatory activity in the rat carrageenan paw edema model ($ED_{50}$=42 mg/kg) compared to the activity of prednisolone (35 mg/kg) and indomethacin (10 mg/kg). However, amentoflavone did not show a significant inhibitory activity against rat adjuvant-induced arthritis, a chronic inflammatory model. In addition, amentoflavone was found to possess a potent analgesic activity in the acetic acid writhing test ($ED_{50}$=9.6 mg/kg) compared to the activity of indomethacin (3.8 mg/kg). These results suggest that amentoflavone may be a potential lead for a new type of anti-inflammatory agents having dual inhibitory activity of group 11 phospholipase $A_2$ and cyclooxygenase.

• Archives of Pharmacal Research
• /
• v.29 no.12
• /
• pp.1074-1079
• /
• 2006

As part of our research on phytochemicals that exert protective effects against diseases related to reactive nitrogen species, we have evaluated the scavenging activity of the yellow leaves of Ginkgo biloba on $ONOO^{-}$. The methanol extract and ethyl acetate fraction obtained from yellow leaves of G. biloba evidenced a marked scavenging activity on authentic $ONOO^{-}$. Repeated column chromatography of the active ethyl acetate soluble fraction on silica gel, Sephadex LH-20, and RP-18, resulted in the purification of 15 known compounds, including sciadopitysin (1), ginkgolide B (2), bilobalide (3), isoginkgetin (4), kaempferol (5), luteolin (6), protocatechuic acid (7), bilobetin (8), amentoflavone (9), ${\beta}-sitosterol$ glucopyranoside (10), kaempferol 3-O-rhamnopyranoside (11), kaempferol 3-O-glucopyranoside (12), kaempferol $3-O-[{6^{'}-O-p-coumaroyl-{\beta}-D-glucopyranosyl(1{\rightarrow}2)-{\alpha}-L-rhamnopyranoside]$ (13), kaempferol 3-O-rutinoside (14), and 6-hydroxykynurenic acid (15). Among the compounds isolated, flavonoids (5, 6 and 11-14), protocatechuic acid (7), and 6-hydroxykynurenic acid (15) all exhibited marked scavenging activities on authentic $ONOO^{-}$. The $IC_{50}$ values of 5-7, 11-14 and 15 were as follows: $2.86{\pm}0.70,\;2.30{\pm}0.04,\;2.85{\pm}0.10,\;5.60{\pm}0.47,\;4.16{\pm}1.65,\;2.47{\pm}0.15,\;3.02{\pm}0.48,\;and\;6.24{\pm}0.27\;{\mu}M$, respectively. DL-Penicillamine ($IC_{50}=4.98{\pm}0.27\;{\mu}M$) was utilized as a positive control. However, the other compounds (1-4, 8-10) exerted no effects against $ONOO^{-}$.

• Journal of Digital Convergence
• /
• v.13 no.5
• /
• pp.337-344
• /
• 2015

Medicinal plants containing wellness-fusion-complex compound are increasingly being pursued as suitable alternative sources of various biological properties. In this study, inhibitory effect of Quintinia acutifolia, which is a New Zealand plant, on P388 murine lymphocytic leukemia cells using MTT [3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl-tetrazolium bromide] assay. Based on $^1H-NMR$, $^{13}C-NMR$ spectral data and other spectral analysis, 2,3,2'',3''-tetrahydroochanaflavone (1) and 2'',3''-dihydroochana-flavone (3) inhibited the leukemia cells were purified from the plants. 2,3,2'',3''-tetrahydroochanaflavone (1) and 2'',3''-dihydroochana-flavone (3) are biflavonoids possessing two basic flavonoids and actively inhibited growth of P388 murine lymphocytic leukemia cells with a 50% inhibitory concentration ($IC_{50}$) of $8.2{\mu}g/mL$ and $3.1{\mu}g/mL$, respectively. Specially, 2'',3''-dihydroochana-flavone (3) possessed unconjugated flavonone system, which isn't consist of a pair with B ring of 2,3,2'',3''-tetrahydroochanaflavone (1). Therefore, the two compounds could be considered as a candidate for development of anticancer drugs and need to much studies in the future.