Investigation of Galatella villosa and G. tatarica for antioxidant, ?-amylase, tyrosinase, lipoxygenase and xanthine oxidase inhibitory activities

Abstract

In the present work two Galatella species, Galatella villosa Rchb.f. and Galatella tatarica (Less.) Novopokr collected from Kazakhstan were subjected to hydrodistillation to yield essential oils (EOs), and to maceration in methanol to yield extracts (MEs). The EOs and MEs were evaluated for antioxidant and in vitro inhibitory activities against ?-amylase, tyrosinase, lipoxygenase and xanthine oxidase enzymes. The EOs of G. villosa and G. tatarica were investigated for chemical composition using GC-FID and GC/MS techniques. The composition of MEs was investigated with LC-MS/MS technique. Monoterpenes, ß- pinene (23.6 %) and ?-pinene (14.4 %) were the main constituents of G. tatarica essential oil, while the oil of G. villosa was characterized not only with monoterpene ?-pinene (9.0 %), but also fatty acid, hexadecanoic acid (10.2%). 3-, 5-, 1,5- and 3,4-caffeoylquinic acids, 3-, 4- and 5-feruloylquinic acids, quercetin and its different glycosides were detected in MEs according to mass spectral data. G. tatarica (IC 50 =74.3 µg/mL) and G. villosa (IC 50 =78.5 µg/mL) extracts showed significant antioxidant activity. In the ß-carotene bleaching test, the extracts demonstrated noteworthy activity (%Inh 44.46 and 41.14). The extracts scavenged ABTS radical as 1.85 mM and 1.27 mM of Trolox. In a concentration of 0.5 mg/mL, the oils showed 89% and 85% inhibition of ?-amylase, while the extracts showed 86% and 78% inhibition at 2 mg/mL concentration, respectively. The EOs demonstrated noteworthy potent LOX enzyme inhibition ranging between 45% and 57%. In xanthine-xanthine oxidase model system, the extracts demonstrated the highest inhibitory potency ranging between 43% and 39%. The present work is the first contribution to the chemistry and biological activities of G. tatarica and G. villosa.