Influence of different extraction solvents on antioxidant and antityrosinase activities of Morus alba Linn. leaf extract.

Wachira Yodthong, Suraphon Chaiwongsar, Penpicha Wanachantararak, Yanee Keereeta, Watee Panthuwat, Benjaporn Saovapha, Tanongsak Sassa-deepaeng*

J. Sci. Agri. Technol. (2020) Vol. 1 (1): 7-17

Abstract

The objective of this study was to investigate the impact of different extraction solvents such as hexane, benzene, ethyl acetate, acetone, ethanol, and water on antioxidant and antityrosinase efficiency of mulberry leaf extract. The sample was extracted from leaves by maceration method. The obtained extract was filtered and evaporated to dryness by using the rotary evaporator prior to measuring the total phenolic content, flavonoid content, antioxidant activity, antityrosinase activity, and morin content in triplicate. The results indicated that the highest antioxidant activity was found in ethyl acetate (EA) fraction of CM60 with ABTS value of 57.8 ± 7.7 % inhibition and DPPH value of 58.2 ± 0.7 % inhibition that were positively related to its phenolic content (36.9 ± 1.3 mg GAE/mg DW). Interestingly, The highest antityrosinase activity was found in acetone fraction of CM60 which inhibited tyrosinase activity by 3.0 ± 0.1 mg KE/mg DW that was positively related to its flavonoid content (32.71 ± 0.1 mg QE/mg DW) and was related to its highest morin content (0.71 ± 0.01 mg/mg DW) measured using HPLC. The present results indicated that the EA fraction of CM60 possessed the highest antioxidant property related to its phenolic content, and the acetone fraction showed the highest antityrosinase activity related to its flavonoid content especially morin which is tyrosinase inhibitor. Both fractions of M. alba were potential candidates for skin protector from oxidative damage and skin-whitening agent development. Further studies are necessary to formulate the compounds responsible for antioxidant and antityrosinase properties and to investigate antityrosinase properties in vivo prior to transferring technology to communities.

Keywords: mulberry, antioxidant, antityrosinase, solvent extraction

Received January 21, 2020. Revised February 9, 2020; March 23, 2020. Accepted March 23, 2020.