• 생약학회지
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• 제24권1호
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• pp.47-53
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• 1993

The seasonal variations of the major six flavonol glycosides(kaempferol 2,6-dirhamnosyl glucoside, quercetin 3-O-rutinoside, kaempferol 3-O-rutinoside, isorhamnetin 3-O-rutinoside, quercetin 3-O-coumaroyl glucorhamnoside and kaempferol 3-O-coumaroyl glucorhamnoside) in Ginkgo biloba leaves were investigated. The contents were determined by HPLC on reversed phase $C_{18}$ column. This result showed that the percentage of six flavonol glycosides decreased during the season from 1.57% in May to 0.39% in November. The content of each flavonol glycoside indicated a similar tendency to decrease. However, the contents of rutinosides of kaempferol, quercetin and isorhamnetin fluctuated markedly than those of coumaroyl glucorhamnosides of kaempferol and quercetin and kaempferol 2,6-dirhamnosyl glucoside.

• 생약학회지
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• 제24권1호
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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.

• 한국동물위생학회지
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• 제35권3호
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• pp.191-195
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• 2012

Accumulated evidence indicate that Ginkgo biloba extract (EGb 761) acts as an antioxidant and scavenger of free radicals as well as influencing apoptotis. Earlier studies have employed the inflammatory agent lipopolysaccharide (LPS) to induce severe sepsis. In the present study, we examined whether the intraperitoneal injection of EGb 761 increases the survival rate of mice in the LPS-induced severe sepsis model. The survival rate was significantly increased by 30% in mice administered with 100 mg/kg of EGb 761 but not in mice administered with 50 mg/kg EGb 761. In addition, pre-treatment with EGb 761 increased the survival rate (30%) but post-treatment with EGb 761 did not. These results suggest that EGb 761 may have clinical potential in preventing sepsis induced mortality.

• Journal of Plant Biology
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• 제26권4호
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• pp.207-216
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• 1983

Mature embryo and developing seedlings of Ginkgo biloba L. were embedded in a paraplast and serially sectioned at 10${\mu}{\textrm}{m}$ to examine vascular differentiation and vascular transition. Procambium and protophloem formed a continuous system along the epicotylhypocotyl root axis and cotyledons in mature embryo, whereas protoxylem was differentiated discontinuously in the cotyledons and rarely in the upper hypocotyl. The traces of the first and second leaf primordia apeared almost at the same time oppositely to each otehr at the epicotyl and alternately with the cotyledon traces in the upper hypocotyl. The trace differentiated bidirectionally toward the epicotyl and root tips. the young root initially formed a diarch xylem. Then, as the traces of the first and second leaves were superimposed, the diarch xylem. Then, as the traces of the first and second leaves were superimposed, the diarch xylem of the root was changed totriarch and tetrarch xylem, respectively. On the formation of primary vascular system of Ginkgo biloba, it is suggested that the primary phloem forms a continuous system throughout the seedling, whereas the primary xylem of the epicotyl is formed independently from that of the root-hypocotyl cotyledon system.

• Toxicological Research
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• 제17권
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• pp.271-280
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• 2001

We report on the applicability oj a method recently developed in our laboratory for measuring the antioxidant potential of isolated chemicals and extracts derived from natural products. Peroxyl radicals generated by thermal homolysis of 2,2'-azobis-amidinopropane (ABAP) oxidize $\alpha$-keto-${\gamma}$-methiolbutyric acid (KMBA) to ethylene, which is monitored by gas chromatography. Inhibition of ethylene formation in the presence of antioxidants that compete with KMBA for peroxyl radicals is the basis of the Total Oxyradical Scavenging Capacity Assay (TOSCA; Winston et al., 1998). Antioxidative activities of water-soluble extracts of American green tea, the anti-hepatotoxic flavonolignan from milk thistle (Silybum marianum) silybin, Ginkgo biloba extract EGb 761, and a series of naturally occuring sesquiterpene lactones (all ger-macranolides found in in fungi, liverworts, and plants) were studied. The specific TOSC value per $\mu$M silybin was 5.2, which is essentially comparable to that of Trolo $x^{ⓡ}$, a water-soluble vitamine E analog. Tea and Ginkgo extracts exhibited potent peroxyl radical scavenging capacity with values, respectively of =1700 and 1000 $\mu$mols Trolo $x^{ⓡ}$ equivalent per gram dry matter. The known anti-inflammatory activity of some germacranolides prompted study of their antioxidant capacity. None of the lactones exhibited antioxidant capacity toward peroxyl radicals comparable to Trolo $x^{ⓡ}$; costunilide, the most lipophilic, had a TOSC value = to glutathione. The potential role of peroxyl radicals in lipidperoxidation, other cellular damage, and var-ious disease states suggest a possible preventive role for silybin, green tea and Ginkgo biloba in oxidative stress caused by these free radical species.ecies.

• 생약학회지
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• 제30권3호
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• pp.280-283
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• 1999

Using the bioassay-guided fractionation and isolation technique, two $PLC{\gamma}1$ inhibitors were isolated from the sarcotestas of Ginkgo biloba (Ginkgoaceae). The structures of these compounds were identified as (3R)-(-)-8-hydroxy-3-(6'-pentadecenyl)3,4-dihydroisocoumarin (1) and 3-heptadecen-2-one (2) by UV, IR, MS, $^1H-NMR$, $^{13}C-NMR$ and $^1H-^{13}C\;COSY$. Isolate compounds 1 and 2 have not been reported previously from the sarcotestas of G. biloba and Ginkgoaceae, respectively. In addtion, these compounds showed significant $PLC{\gamma}1$ inhibitory effects with the $IC_{50}$ of the 9.7 (1) and $25.6\;{\mu}M\;(2)$.

• Preventive Nutrition and Food Science
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• 제7권1호
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• pp.18-21
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• 2002

The extract of Ginkgo biloba leaves was measured for inhibitory activity against xanthine oxidase. Aceton extract of G. biloba leaves showed strong inhibitory activity. Inhibitory activities of the fractionated extract were in the order of water > ethyl acetate fractions. Two fractions exhibiting strong inhibitory activities ware further purified via repeated silica gel, Amberlite IRN-78, Polyclar AT, and Sephadex LH-20 column chromatographies. Active components were isolated and identified through $^1$H-NMR and $^{13}$ C-NMR. The compounds were characterized as kaempferol 3-Ο-$\alpha$-(6$^{"′}$-p-coumaroylglucosyl-$\beta$-1,4-rhamnoside), and quercertin 3-Ο-$\alpha$-(6$^{′}$-p-coumaroylglucosyl-$\beta$-1,4-rhamnoside).

• 한국잡초학회지
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• 제17권4호
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• pp.421-430
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• 1997

채취시기(採取時期)를 달리한 초록과 노란은행잎으로부터의 수용추출물(水溶抽出物)에 대한 벼, 피, 바랭이 및 상추의 제초활성검정(除草活性檢定)과 지방산(脂肪酸) 성분(成分)과 페놀성 물질(物質)을 분리(分離) 동정(同定)하여 얻어진 결과(結果)는 다음과 같다. 1. 은행잎 수용(水溶) 추출물(抽出物)은 벼, 피, 바랭이, 상추의 발아(發芽)와 생육(生育)을 크게 억제(抑制)시켰으며, 특히 20% 수용추출액(水溶抽出液)인 경우는 억제효과(抑制效果)가 뛰어났다. 초록과 노란은행잎 수요 추출물간의 생리활성정도는 별 차이가 없었다. 2. 은행잎의 지방산(脂肪酸)을 검정(檢定)한 결과(結果), 지방산(脂肪酸)이 검정(檢定)되었으며, 그 중에서도 Linolenic acid, Palmitic acid가 많이 포함(包含)되어 있었다. 또한 계절에 따라 은행잎에 함유(含有)된 지방산(脂肪酸)의 함량(含量)이 다소 변화(變化)함을 알 수 있었다. 3. GLC로 phenolic acids를 동정(同定)한 결과(結果), 모든 fraction에서 Salicylic acid의 높은 비율(比率)을 관찰(觀察)할 수 있었으며, 또한 p-coumaric acid, phloroglucinol 등도 검정(檢定)되었다.

• Journal of Plant Biology
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• 제35권4호
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• pp.333-338
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• 1992

다양한 발달단계에 있는 은행종자의 자성배우체, 자엽 및 유근에서 탄수화물의 함량과 여러 가수분해효소(아밀라제, 인버타제 및 인산가수분해효소)의 활성을 비교하였다. 종자의 초기발아시에 아밀라제의 활성이 크게 증가함에 따라 자성배우체의 전분이 현저한 감소를 보인 반면 수용성 당들은 증가하였다. 인버타제의 활성은 건조한 종자에서는 매우 낮았으며 바라된 자엽과 유근에서 점진적으로 증가하였다. 인산가수분해효소의 활성은 유근이 신장되는 단계에서 변화를 나타내었으며 산성-인산가수분해효소가 알카리성-인산가수분해효소보다 더 높은 활성을 보였다.

• Biomolecules & Therapeutics
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• 제6권3호
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• pp.269-275
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• 1998

These studies were conducted to investigate the antiinflammatory effects and the mechanism of action of natural products. We used the methods of "carrageenan induced foot edema" , "PAF (platelet activating factor) induced foot edema" , "inhibition test of vascular permeability" , "inhibition test of white blood cell migration" , "formation of granuloma" and "adjuvant induced arthritis" to examine the antiinflammatory erects of Angelica gigas, Ledebouriella seseloides, Ginkgo biloba and Bamboo salt (Jukyom). The oral administration of the water extract of Angelica gigantis radix, the methanolic extract of Ginkgo folium and the aqueous solution of Bamboo salt showed antiinflammatory effect on carrageenan and PAF induced foot edema in SD rat at a dose of 1 g/kg. The same administration of methanolic extract of Ginkgo folium also inhibited the vascular permeability in mice. The aqueous solution of Bamboo salt inhibited the formation of ganuloma in SD rats at a oral dose of 1 g/kg. Angelica gigantis radix seems to have antiinflammatory effect by inhibition of PAF.