Antiproliferative and antibacterial activity evaluation of red microalgae Rhodosorus marinus

Abstract

Antiproliferative activity of three extracts obtained from red microalgae Rhodosorus marinus was evaluated against cervical (HeLa), colon (HCT 116), lung (A549), prostate (22Rv-1) and breast (HCC38 and MDA-MB-231) cancer cell lines. Antibacterial activity of these extracts was also tested against Salmonella choleraesuis, Listeria monocytogenes and Staphylococcus aureus. All extracts were obtained from lyophilized biomass of red microalgae. Extract A was obtained using 40% ammonium sulfate precipitation and gel filtration chromatography with G-25 sephadex. Extract B was subjected to a similar process, but 60% ammonium sulfate precipitation was used. Extract C was obtained by methanol extraction and hydrophobicity chromatography using amberlite XAD-2. Protein concentration was determined in two extracts and total phenols in one extract, using Bradford and Folin techniques. Antiproliferative activity was evaluated at extract concentrations ranging from 0.125 to 1 mg/ml, using the spectrophotometric technique MTT (3 - (4,5 - dimetiltiazolyl - 2) - 2,5 - diphenyltetrazolium bromide). The antibacterial activity was evaluated by the impregnated disk test. Extract C showed antiproliferative activity against almost all cancer cell lines with an IC₅₀ of 0.5 (HCT 116), 0.8 (HeLa), 0.9 (MDA-MB-231), 0.1 (HCC38), and 0.4 (22Rv-1) mg/ml, whereas none of the tested extracts showed antibacterial activity under experimental conditions.

Keywords: Rhodosorus marinus, red microalgae, antibacterial activity, antiproliferative activity, methanolic extract. 

African Journal of Biotechnology, Vol 13(43) 4169-4175