• Korean Journal of Pharmacognosy
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• v.24 no.1
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• pp.54-57
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• 1993

The seasonal variations of five biflavones from Ginkgo biloba leaves from May to November were investigated by a reversed phase HPLC method. The total amount of biflavones was increased with time to reach its maximum in yellow autumnal leaves. Each biflavone showed a similar tendency. It increased rapidly about 3.1-fold from May to June and thereafter gradually increased about 2.5-fold. The ratio of each biflavone content to the total amount of biflavones was in the order of as follows: isoginkgetin>sciadopitysin>bilobetin>ginkgetin>amentoflavone.

• Korean Journal of Pharmacognosy
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• v.21 no.2
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• pp.111-120
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• 1990

Five biflavones and sevenflavonolglycosideswereisolatedfromtheleaves of Ginkgo biloba. They were sciadopitysin(1), ginkgetin(2), isoginkgetin(3), bilobetin(4), amentoflavone(5), kaempferol 3-O-[$6'-O-{\rho}-coumaroyl-{\beta}-_D-glucopyranosyl(1{\rightarrow}2)-{\alpha}-_Lrhamnopyranoside$](6), quercetin 3-O-[$6'-O-{\rho}-coumaroyl-{\beta}-_D-glucopyranosyl(1{\rightarrow}2)-{\alpha}-_Lrhamnopyranoside$](8), rutinosides of kaempferol(7), isorhamnetin(9), quercetin(10), laricitrin(11), and kaempferol 3-O-($2',6'-{\alpha}-_L-dirhamnopyranosyl-{\beta}-_{D}-glucopyranoside$)(12). The structures were established by spectroscopic and chemical methods.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.195-195
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• 1998

Ginkgetin was previously reported as an inhibitor of group II phospholipase A$_2$. It also inhibited in vitro arachidonate release from the activated macrophages and lymphocyte proliferation. These previous studies suggested an anti-inflammatory nature of ginkgetin, especially on chronic inflammation. In fact, ginkgetin showed potent anti-inflammatory activity against rat adjuvant-induced arthritis, a chronic inflammatory animal model, with comparable analgesic activity. In order to investigate the action mechanisms, tumor necrosis factor and interferone release were studied from human PMMC. It was found that ginkgetin clearly inhibited release of these cytoknes from human PMMC. Ginkgetin was also found to inhibit immunoglobulin M production at 1 - 10 uM. These results may contribute to antiarthritic activity of ginkgetin in vivo.

• Journal of Korea Foresty Energy
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• v.24 no.2
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• pp.24-30
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• 2005

Four compounds, (+)-catechin (1), (-)-epicatechin (2), myricitrin (3), and hinokiflavone (4), were isolated from the needles of Juniperus occidentalis Hook. The structures of the isolated compounds were established by NMR and MS spectrometer. The antioxidant activity of the isolated compounds was determined by measuring free radical scavenging activity with DPPH and the results indicated that compound 1, 2, and 3 showed better activity than the controls, while compound 4 had weak activity compared with ${\alpha}-tocopherol$, BHT, and curcumin.

• YAKHAK HOEJI
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• v.56 no.6
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• pp.366-371
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• 2012

In this present study, we determined whether or not there is an immunoadjuvant effect of ochnaflavone, a biflavone isolated from Lonicera japonica. As an antigenic source, the cell wall (CACW) of Candida albicans, a fungal pathogen, was used. CACW consists of 95% carbohydrate (mannan). In the experiments, BALB/c mice were immunized with emersion forms of CACW combined with or without ochnaflavone (Och) in the presence of IFA containing mineral oil or CACW alone. Then, the amounts of antisera collected from these mice groups were measured by the ELISA method. Data from these experiments showed that CACW combined with Och (CACW/Och/IFA) provoked the production of antisera app. 2.2 or 5 times more than the corresponding CACW/IFA or CACW alone (CACW/DPBS), respectively, in mice (P<0.05). We further examined the immune response type induced by Och. Analysis of the values of the IgG1/IgG2a ratios obtained from IgG isotyping revealed that Och induced Th2-immunity more dominantly than Th1. This finding was confirmed by cytokine profile. CACW/Och/IFA formulation induced IL-4 (Th2-type cytokine) more than IFN${\gamma}$ (Th1-type cytokine) as compared with CACW/IFA and CACW/DPBS formulations (P<0.05). All data combined, Och appears to have an immunoadjuvant activity that may convert Th1 immunity into Th2 immunity.

• Biomolecules & Therapeutics
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• v.15 no.3
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• pp.169-174
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• 2007

In the present study, we investigated the neuroprotective effects of standardized Ginkgo biloba extract (GBB) (total terpene trilactones, 13 ${\pm}$ 3%; biflavone, 4.5 ${\pm}$ 1.5%; flavonol glycoside, < 8%; proanthocyanidine, under detection limit) on ischemia-reperfusion-induced brain injury in the rats. Ischemia was induced by the intraluminal occlusion of the right middle cerebral artery for 2 h and reperfusion was continued for 22 h. GBB was orally administered, promptly prior to reperfusion and 2 h after. Total infarction volume in the ipsilateral hemispheres of ischemia-reperfusion rats were significantly reduced by treatment with GBB in a dose-dependent manner (P<0.05). The therapeutic time window of GBB was 3 h in this ischemia-reperfusion rat model. Furthermore, GBB also significantly inhibited increased neutrophil infiltration of ischemic brain tissue, as estimated by myeloperoxidase activity. These findings suggest that GBB plays a crucial protective role in ischemia-induced brain injury, in part, via inhibition of neutrophil infiltration, and suggest that this GBB could serve as a neuroprotective agent following transient focal ischemic brain injury.