Maackiain 3-O-(6'-O-malonyl-beta-D-glucopyranoside) from Oudneya africana, a powerful inhibitor of porcine kidney acylase I.
The inhibitory effect of phenolic extracts of several plants from the Algerian Atlas used traditionally in Arab folk medicine was tested on the porcine kidney acylase I activity. An endemic Saharan plant of the Brassicaceae family, Oudneya africana, has shown a strong inhibitory effect. The active compound was isolated and purified by semi-preparative HPLC and HPLC-photodiode array detection, and structurally determined using 1H, 13C NMR and mass spectroscopy methods. Results indicate that maackiain 3-O-(6'-O-malonyl-beta-D-glucopyranoside) showed a competitive inhibition of porcine kidney acylase I with a Ki value of 11 microM. The malonyl moiety appeared to be a structural key element for the inhibitory activity. This observation indicates interesting structure-activity relationships for the inhibitory action of this compound on the acylase I and its potential role in the toxicity of haloalkene-derived mercapturates and that of the enzyme in detoxication and bioactivation.