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茉莉花（マツリカ、Jasminum sambac）は、アラビアからインドにかけて分布するモクセイ科の熱帯性常緑低木である。乾燥した花は香りが強く、食品、化粧品に利用されるとともに、伝統医学において下痢、発熱、結膜炎などの治療に用いられている。我々はメディシナルフラワーの機能性解析研究を行っており、スクリーニングの結果から、茉莉花の花部エキス（JSFE）が、リポポリサッカライド（LPS）刺激マウスマクロファージ様RAW264 細胞においてプロスタグランジンE２（PGE２）および一酸化窒素（NO）を抑制することを見出した。そこで本研究では、JSFEの抗炎症作用を解明することを目的として、活性成分の単離・同定を行った。まずJSFEを水に懸濁後、ヘキサン、ジクロロメタン、酢酸エチル、ブタノールで順次分画し、各分画のPGE2 および NO 抑制能を調べたところ、酢酸エチル画分が毒性を示さずPGE２および NO を顕著に抑制した。さらに各種クロマトグラフィーを繰り返すことで、酢酸エチル画分から quercetin (1)、kaempferol (2)、benzyl β-D-glucopyranoside (3)を単離同定した。1-3のうち、1および2はPGE２および NO を抑制し、その作用は1の方が強かった。一方、3は抑制作用を示さなかった。これらの結果より、1および2が JSFE の抗炎症作用に寄与することが示唆された。, Jasminum sambac (L.) Aiton, commonly known as Arabian jasmine, is a small shrub with fragrant and white flowers that is native to India. The flowers are used in various applications such as cosmetics, food, and folk medicine. In our preliminary screening of medicinal flowers, a methanolic extract of J. sambac flower (JSFE) was found to inhibit prostaglandin E2 (PGE2) and nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine macrophage-like RAW264 cells. This study aimed to isolate active compounds having anti-inflammatory potential from JSFE. To identify the active compounds that suppress PGE2 and NO production, JSFE was suspended in water and successively partitioned using hexane, dichloromethane (CH2Cl2), ethyl acetate (EtOAc), and n-butanol (n-BuOH). Comparative analysis revealed that the EtOAc fraction inhibited PGE2 and NO production without causing cytotoxicity. Bioassay-guided separation of the EtOAc fraction isolated three compounds: quercetin (1), kaempferol (2), and benzyl β-D-glucopyranoside (3). Among the isolated compounds, 1 and 2 inhibited PGE2 and NO production without causing cytotoxicity, and the inhibitory potency of 1 was higher than that of 2. In contrast, 3 did not show significant inhibition. These results suggest that 1 and 2 can be attributed to the anti-inflammatory potential of JSFE.

In the course of finding new antifungal natural compounds against plant pathogens, the methanol extract of Desmodium triflorum was investigated phytochemically. From n-butanol-soluble fraction, seven compounds (1–7) were isolated and structurally elucidated. Of which, six compounds belong to flavone 6- or 8-C-glycoside class (1–6). Three major compounds (1–3) exhibited moderate in vitro antifungal activity against Sclerotium rolfsii, Fusarium oxysporum f. sp. cubense, and Phytophthora palmivora. Compound 1 (IC50 = 162.1 μg/mL) was most active against S. rolfsii in a dose-dependent manner. At 300 μg/mL, compounds 1 and 2 significantly inhibited P. palmivora, whereas compound 3 lacked effectiveness. In addition, the nanoemulsion of the methanol extract with a droplet size of 12.2 nm displayed an excellent inhibition against S. rolfsii and P. palmivora compared with the normal extract. The presence of 1 (0.846%) and 2 (0.759%) in the methanol extract may attribute to the antifungal activity of D. triflorum. These results proved the potential of D. triflorum and its C-glycoside flavonoids against phytopathogenic fungi for the first time. Besides, an enhancement in the effectiveness of nanoemulsion containing D. triflorum extract against the fungi was confirmed. The structural characteristics of 1 and 2 could be considered to develop new fungicidal substances in the future.

In the course of finding new antifungal natural compounds against plant pathogens, the methanol extract of

Phytochemical study on the methanolic extract of the leaves of Vietnamese plant Gardenia philastrei Pierre ex Pit. has led to the isolation of a new cycloartane coronalyl acetate (1) together with six known ones, coronlolide methyl ester (2), sootepin D (3), coronalolide (4), coronalolic acid (5), sootepin G (6) and 23-deoxojessic acid (7). Their structures were elucidated by a combination of 2 D NMR and HR-ESI-MS spectroscopies. These compounds (1-7) were tested for their anti-inflammatory activity. The result showed that six compounds (1-6) inhibit LPS-induced nitric oxide production in RAW264.7 macrophages with their IC50 values ranging from 3.76 − 75.47 µg/mL. This is the first report on the chemical constituents and anti-inflammatory activity of the G. philastrei.

Spatholobus suberectus vine stem is an important medicinal material in Chinese, Vietnamese, and Korean traditional medicines. Its decoction has long been used to treat blood disorders, such as anemia and menstrual irregularity, as well as rheumatoid diseases. Previous phytochemical investigations characterized 88 compounds from S suberectus, which mainly belonged to the phenolic class, especially of the flavonoid type. Pharmacological studies showed the beneficial effects of extracts of the plant on the cardiovascular tract, which is ethnopharmacologically relevant to the plant's use in traditional medicine. Besides that, the extracts and isolated compounds also exhibited antimicrobial, anticancer, antiinflammatory, and antioxidant activities. The past study results support the use of S suberectus vine stem in traditional medicine and also revealed new directions of pharmacological effects of this medicinal plant.

The root of plant Polygala arillata has been used in the Oriental medicine as a tonic and for the treatment of certain diseases. Our current research on phytochemical profile of the roots of P. arillata led to the isolation of a new oligosaccharide ester (1, polygaloside), a new glucose ester (7, arillatoside), along with five known sucrose esters (2–6). Their structures were elucidated on the basis of extensive chemical and spectroscopic methods as well as comparison with those reported in the literature. The occurence of various oligosaccharide esters in P. arillata including unique compounds plays taxonomical impact and suggests potential in medicinal uses of the title plant.

The main goal of this study was to isolate and screen the therapeutic potential of some terpenoids from Dicliptera chinensis (L.) Nees grown in Vietnam. From the leaves of Dicliptera chinensis (L.) Nees (Acanthaceae) collected in Nam Dinh province, one new terpenoid (1) together with five known (2-6) were isolated by chromatographic methods. These compounds were identified as 6-hydroxy-1,12-oleanadien-3-on (1), 1β,4β-dihydroxyeudesm-11-ene (2), 3β-hydroxylup-20(29)-en (3), stigmast-5,22-dien-3-β-ol (4), rutaevine (5), mangiferin (6). All of them were isolated from this plant for the first time. Compound 4 showed signficant potential for COX-2 inhibitory effects with IC50 values of 7.32± 1.82 µg/mL. These pilot results suggest the potential of Dicliptera terpenoids for treating inflamatory conditions.