Fractional extraction of compounds from grape seeds by supercritical fluidextraction and analysis for antimicrobial and agrochemical activities

White grape seeds were subjected to sequential supercritical fluid extracti on. By increasing the polarity of the supercritical fluid using methanol as a modifier of CO2, it was possible to fractionate the extracted compounds. Two fractions were obtained; the first, which was obtained with pure CO2, contained mainly fatty acids, aliphatic aldehydes, and sterols. The second fraction, obtained with methanol-modified CO2, had phenolic compounds, main ly catechin, epicatechin, and gallic acid. The fractions were bioassayed. A ntimicrobial activities were checked on human pathogens, and a high degree of activity was obtained with the lipophilic fraction. Agrochemical activit ies on phytopathogenic fungi and activities on the etiolated wheat coleopti le bioassay were also checked. The more polar fraction was active in the la tter bioassay.