Biologically active extracts from common milkweed seed oil

Plants and herbs have been extensively studied in search for the new therapeutic agents of pharmacological importance. Among them, the milkweed is a genus of herbaceous perennial, dicotyledonous plants that contains over 140 known species. While the seed floss of the milkweed plant is commercialized as a hypoallergenic fiber fill material, the potential market applications of the milkweed seeds are limited. The objective of this study was to investigate and evaluate the potential of cold-pressed oil extracted from the seeds of the milkweed species Asclepias syriaca for biomedical uses. The antioxidant potential of different oil concentrations was measured against a solution of 0.1 mM 2,2-diphenyl-1-picrylhydrazyl (DPPH) in 80% methanol. The absorbance of the color developed by DPPH was measured at 517 nm and a standard regression line for trolox was used to calculate the DPPH scavenging activity. The maximum antioxidant activity was found to be 60.25%. The total phenolic content was examined using Folin-coicalteu’s phenol agent. It was determined in terms of gallic acid equivalents (GAE) and ranged from 22.37 to 194.66 mg GAE/ml. Milkweed seed oil was tested against six gram-positive and gram-negative bacteria, however, it exhibited anti-bacterial activity only against one gram-positive strain - Streptococcus pyogenes. Studies on the anticarcinogenic effect of milkweed seed oil on human breast cancer cells (cell line MCF7) suggested apoptosis through enhanced mitochondrial ROS production and inhibited G1 cell cycle arrest. The significance of the biological activities of milkweed seed oil will be discussed.