An in vitro study of amygdalin alone and complexed with Se(IV), Au(III), Ru(III), and V(III) ions: Structure, morphology, and pharmacology

Amygdalin is a naturally occurring product and was considered to be a natural cancer cure; however, its anticancer effects remain highly controversial. Furthermore, the bioactivity of amygdalin in metal- and nonmetal-complexes has not been explored. The objectives of this work is to synthesize four amygdalin complexes using Se(IV), Au(III), Ru(III), and V(III) ions and to evaluate their biological activity using four microbes and two human cancer cell lines. Spectral, analytical, and thermal analyses were used to elucidate the complexes' structures. The Kirby-Bauer disc diffusion method was used for antibacterial screening and an MIT-based assay was used to determine cytotoxicity towards MCF-7 and HepG2 cell lines. The IC50 of the Au(III) complex on MCF-7 and HepG2 cells were 35.2 +/- 0.9 and 21.8 +/- 1.4 mu g/ml, respectively, while the IC50 of free amygdalin on these cells exceeded 500 mu g/ml. Free amygdalin has a strong effect on Gram-negative bacteria and no effect on HepG2 and MCF-7 cell proliferation. The amygdalin Au(III) complex inhibited the proliferation of HepG2 and MCF-7 cells. (C) 2019 Elsevier B.V. All rights reserved.