Phytochemical constituents and anti-tyrosinase activity of Macadamia integrifolia leaves extract.

MACADAMIA; GALLIC acid; ETHYL acetate; PHENOL oxidase; EXTRACTS

Macadamia integrifolia Maiden & Betche is cultivated around the world for its highly valued nuts (macadamia nuts). Although the chemical composition of the edible macadamia oil has been repeatedly investigated, other plant organs have not been phytochemically or biologically assessed. In this study, ethanolic extract of M. integrifolia leaves was phytochemically investigated which led to the isolation of 6 compounds. Two functional galactolipids, i.e., monogalactosyl diacylglycrol 36:4 (MGDG 36:4), digalactosyl monoacylglycerol 18:2 (DGMG 18:2), gallic acid and protocatechuic acid were identified in the genus Macadamia for the first time, in addition to the cyanogenic glycoside dhurrin and β-sitosterol. Additionally, anti-tyrosinase activity of the extract, its fractions and isolated compounds was investigated and a good tyrosinase inhibitory activity was observed for the extract, IC50=85 µg/mL and its polar fractions (ethyl acetate at 60 µg/mL and n-butanol at 75 µg/mL), with gallic acid showing strong anti-tyrosinase activity at IC50 56 µg/mL. [ABSTRACT FROM AUTHOR]

Copyright of Natural Product Research is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)