EN
The betel vine, Piper betle L. is a native plant of Southeast Asia, well known for its significant medicinal properties and nutritional values. The leaves have stimulant, antiseptic and sialagogue properties making them a popular masticatory in South and Southeast Asia. Several „lines" or „ecotypes" of betel vines have been observed in Malaysia, popularly categorized as Malay, Indian or Chinese „sireh". Piper betle (probably the Chinese type) has been reported to contain a series of anti-inflammatory neolignans, acting specifically as antagonists to PAF (platelet activating factor), in vitro. In a preliminary screen for anti-inflammatory plants using a in vitro enzyme assay, Malay „sireh" was also found to be active. A methanol extract of the leaves inhibited lipoxygenase, one of the many known enzyme mediators of inflammatory processes, by more than 90% at 100 ng/ml. The enzyme-inhibition activity to be concentrated in the hexane and dichloromethane solubles. Further attempt was made to isolate the active component(s) through bioassay guided fractionation with the enzyme model as the bioassay guide. Our results showed that, for this enzyme model, the activity could be due to several components acting together or synergistically. When these individual components were isolated, their activities were found to be markedly reduced and some were even observed to stimulate rather than inhibit inflammation. Nevertheless, the anti-inflammatory property of the plant was further evaluated in vivo via the TPA-induced mouse ear oedema and carrageenan-induced rat paw oedema assays. Involving different mechanisms of action, the two tests are frequently used to detect topically and orally active anti-inflammatory agents, respectively. The plant was found to be active in both assays, thus confirming its anti-inflammatory properties. The dichloromethane extracts of betel leaves were found to significantly inhibit TPA-induced oedema by 83% at a dose of 2 mg/ear, and the carrageenan-induced oedema by 37% at a dose of 1 g/kg. This study has provided some scientific proof for the anti-inflammatory property of the plant.
PL
Wstępne badania biochemiczne wykazały, że metanolowy wyciąg z liści Piper betle L., rośliny pochodzącej z południowo-wschodniej Azji, w stężeniu 100 (ig/ml hamował w ponad 90% aktywność lipooksygenazy, jednego z enzymów odpowiedzialnych za powstawanie procesu zapalnego. W badaniach farmakologicznych najsilniejsze działanie przeciwzapalne przejawiał wyciąg di- chlorometanowy z liści omawianej rośliny. Hamował on po podaniu miejscowym w dawce 2 mg obrzęk ucha myszy wywołany TPA w 83% oraz po podaniu doustnym w dawce 1 g/kg obrzęk łapy szczura wywołany karageniną w 37%. Wśród substancji o działaniu przeciwzapalnym wyróżniały się w wyciągach z liści Piper betle pochodne chawikolu - chawibetol i octan chawibetolu.