Inhibitory activity of Podospermum canum and its active components on collagenase, elastase and hyaluronidase enzymes

Present study is aimed to investigate in vitro inhibitory effects of the extract prepared from the aerial parts of Podospermum canum (syn: Scorzonera cana var. jacquiniana) (Asteraceae) on hyaluronidase, collagenase, and elastase enzymes using a bioassay-guided fractionation. Inhibitory effects of the extract, sub-extracts, fractions obtained by column chromatography, and isolated compounds on collagenase, elastase, and hyaluronidase were performed by using in vitro enzyme inhibitory assays based on spectrophotometric evaluation. The methanolic extract obtained from P. canum exhibited strong inhibitory activities on elastase and collagenase while the insignificant activity was observed on hyaluronidase. Through bioactivity-guided fractionation, the ethyl acetate and remaining water sub-extracts obtained from the methanolic extract displayed significant inhibitory activities on collagenase and elastase, while petroleum ether and chloroform extracts did not show any inhibitory activity. Eleven known compounds: arbutin, 6'-O-caffeoylarbutin, cichoriin, 3,5-dicaffeoylquinic acid methyl ester, apigenin 7-O-beta-glucoside, luteolin 7-O-beta-glucoside, apigenin 7-O-beta-rutinoside, isoorientin, orientin, vitexin, procatechuic acid, and new compound 4-hydroxy-benzoic acid 4-(6-O-alpha-rhamnopyranosyl-beta-glucopyranosyl) benzyl ester have been obtained from ethyl acetate sub-extract. Results of the present study have revealed that apigenin 7-O-beta-glucoside, luteolin 7-O-beta-glucoside, apigenin 7-O-beta-rutinoside, and isoorientin showed potent enzyme inhibitory activities. However, methanolic extract of P. canum displayed a greater inhibitory activity than fractions and isolated compounds both on collagenase and elastase.