Isolation of Valuable Bioactive Compounds from Aerial Parts of Black Wattle, a Forest Solid Waste

This study aimed at obtaining an extract enriched in phenolic compounds from the aerial parts of black wattle waste (Acacia mearnsii De Wild), characterization of its composition, and investigation of its antioxidant potential and preclinical toxicological profile. First, a phenolic compound enriched extract (PCEE) was obtained by sequential fractionation. Thereafter, the main classes of secondary metabolites present in PCEE were identified and quantified. The antioxidant, cytotoxic, and cytogenotoxic activities were evaluated using in vitro assays. Toxicological effects on locomotor function were assessed using in vivo open field and plus maze models. Cinnamic acid and coumarin were isolated from the PCEE and identified. In addition, high contents of phenolic compounds and flavonoids, responsible for the promising antioxidant activity, were quantified. The extract should a dose-dependent in vitro cytotoxicity in HaCaT cells. In the cytogenotoxicity bioassay, no differences in the mitotic index and micronuclei frequency were observed between PCEE and negative control groups. Also, there were no significant effects of the extract on the motor function. Taken together, these results show that the aerial parts of A. mearnsii can be used for obtaining bioactive compounds with the potential for promoting human and animal health.