William H. Witola
University of Illinois at Urbana-Champaign, USA
Title: Anti-Protozoal Efficacy of 3-Deoxyanthocyanidins-rich Fractionated Extracts from Sorghum bicolor
Biography
Biography: William H. Witola
Abstract
We investigated dried red leaf extracts of S. bicolor for activity against Toxoplasma gondii tachyzoites. S. bicolor red leaf extracts were obtained by bioassay-guided fractionation using ethanol and ethyl acetate as solvents. Analysis of the crude and fractionated extracts using Electrospray Ionization Mass Spectrometry (ESI-MS) showed that they contained significant amounts of apigeninidin, luteolinidin, 7-methoxyapigeninidin, 5-methoxyapigeninidin, 5-methoxyluteolinidin, 5-7-dimethoxyapigeninidin or 5-7-dimethoxyluteolinidin, based on mass per charge (m/z). When tested in vitro, the IC50 values of the inhibitory activity of the ethanol and ethyl acetate extracts against T. gondii’s growth were 2.3- and 4-fold, respectively, lower than their cytotoxic IC50 values in mammalian cells. Ethyl acetate extracts fractionated in chloroform-methanol and chloroform had IC50 values against T. gondii that were 56.1- and 3-fold lower than their respective cytotoxic IC50 values in mammalian cells. These anti-parasitic activities were found to be consistent with those of the respective pure 3-deoxyanthocyanidin compounds identified to be contained in the fractions in significant amounts. Further, we observed that, the position and number of methoxy groups possessed by the 3-deoyanthocyanidins influenced their anti-parasitic activity. Together, our findings indicate that S. bicolor red-leaf 3-deoxyanthocyanidins-rich extracts have potent in vitro inhibitory activity against the proliferative stage of T. gondii parasites.