• Natural Product Sciences
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• v.1 no.1
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• pp.55-60
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• 1995

In the course of evaluation of hepatoprotective components against alcohol-induced toxicity from Aloe spp., the methanol extract was found to cause a significant inhibition of rat liver cytosolic alcohol dehydrogenase activity. Systematic fractionation of active tractions monitored by bioassay led to isolation of four compounds; aloe-emodin, aloenin, ethylidene-aloenin and ${\beta}-sitosterol$, which were estimated as active principles for inhibition of c-ADH and c-ALDH activities in vitro.

• Nuclear Engineering and Technology
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• v.2 no.2
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• pp.73-84
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• 1970

The metabolism of sterol precurosor in leaves of Salanum andigena grafted between photoinduced and noninduced plant was investigated with the use of (2-$^{14}$ C) mevalonic acid. By the technique of the preparative gas-liquid chromatography, radioactive compounds of squalene, 4,4’-dimethylsterols and 4-demethylsterol were isolated and determined quantitatively. When labeled mevalonic acid n as applied to leaves radioactivity was extensively incorporated into non-saponifiable materials of lipid fraction and aqueous fraction (ethanol-water fraction). Radioactivity of 14C derived from (2-$^{14}$ C) mevalonic acid was transmissible from photoinduced plant to non-induced plant across the graft union, as tuberization hormone was, and incorporated into the sterols of the non-induced plant. Inhibitors of sterol biosynthesis, SK & F 7997 and nicotinic acid, are effective suppressors of tuber growing, if applied to leaves during photoinduction period. The experimental results suggest that certain substance containing isoprene unit, or sterol-like compound may participate in tuber growing.

• Natural Product Sciences
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• v.25 no.4
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• pp.348-353
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• 2019

Soluble epoxide hydrolases (sEH) are enzymes present in all living organisms, metabolize epoxy fatty acids to 1,2-diols. sEH in the metabolism of polyunsaturated fatty acids plays a key role in inflammation. In addition, the endogenous lipid mediators in cardiovascular disease are also broken down to diols by the action of sEH that enhanced cardiovascular protection. In this study, sEH inhibitory guided fractionation led to the isolation of five phenolic compounds trans-resveratrol (1), trans-piceatannol (2), sulfuretin (3), (+)-balanophonin (4), and cassigarol E (5) from the ethanol extract of the seeds of Passiflora edulis Sims cultivated in Vietnam. The chemical structures of isolated compounds were determined by the interpretation of NMR spectral data, mass spectra, and comparison with data from the literature. The soluble epoxide hydrolase (sEH) inhibitory activity of isolated compounds was evaluated. Among them, trans-piceatannol (2) showed the most potent inhibitory activity on sEH with an IC₅₀ value of 3.4 μM. This study marks the first time that sulfuretin (3) was isolated from Passiflora edulis as well as (+)-balanophonin (4), and cassigarol E (5) were isolated from Passiflora genus.