title: Tyrosinase-inhibitory activity in some species of the lichen family Graphidaceae.
abstract: Twenty-five species of the lichen family Graphidaceae have been investigated for tyrosinase-inhibitory activity. Tyrosinase-inhibiting material was extracted with solvents methanol, acetone, ethanol, dimethyl sulphoxide in water, and with water only. Methanol has been found to be suitable for extracting adequate amounts of tyrosinase-inhibiting component from the natural thallus. The lichen species such as Graphina glaucorufa, Graphina multistriata, Graphina salacinilabiata, Graphis assamensis, Graphis nakanishiana, and Phaeographopsis indica, have shown inhibition of tyrosinase over a range of 30-78%. Half-inhibiting concentration (IC(50), microg/ml) has been found to be much lower than the standard tyrosinase inhibitors and thus can compete with other commercially available tyrosinase inhibitors. The extracts of these species have been found to be stable at 4 degrees C.
authors.affiliation: Plant Science Division, Agharkar Research Institute, G. G. Aagarkar Road, Pune 411 004, India. bcbehera2002@yahoo.co.in
authors.forename: Bhaskar C
authors.initials: BC
authors.lastname: Behera
authors.forename: Bharathi
authors.initials: B
authors.lastname: Adawadkar
authors.forename: Urmila
authors.initials: U
authors.lastname: Makhija
mesh_terms: D001203:Ascomycota / Q000737:chemistry* / Q000187:drug effects / Q000254:growth & development; D003470:Culture Media / Q000737:chemistry; D016166:Free Radical Scavengers / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D020128:Inhibitory Concentration 50; D008011:Lichens / Q000737:chemistry* / Q000187:drug effects / Q000254:growth & development; D000432:Methanol / Q000737:chemistry; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D008517:Phytotherapy; D013045:Species Specificity; D013395:Sucrose / Q000378:metabolism / Q000494:pharmacology; D013481:Superoxides / Q000378:metabolism; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors
chemical_list: D003470:Culture Media; D016166:Free Radical Scavengers; D013481:Superoxides; D013395:Sucrose; D014442:Monophenol Monooxygenase; D014969:Xanthine Oxidase; D000432:Methanol