Synergism of specific maca phenotypes (Lepidium peruvianum) in combination with saw palmetto (Serenoa repens) extract for chemoprevention of prostate cancer as determined in in vitro cytotoxicity assays on human epithelial and prostate cancer cells

Selected phenotypes of dried maca (Lepidium peruvianum) hypocotyls and supercritical CO2 extract (USPlus®) of saw palmetto (Serenoa repens) were used to determine their targeted, cytotoxic action in prostate cancer cells. Fingerprinting by HPLC-MS and PCA analysis showed compositional differences in glucosinolates, amides, macamides, and other alkaloids, which varied based on the color and the size of hypocotyls. These phytochemical differences translated into a higher antioxidant potential of red maca than black maca samples. The greatest COX-2 inhibition was demonstrated with a combination of red maca: saw palmetto (67%:33%) and red maca: saw palmetto: black maca (25%:50%:25%). The LNCaP androgen-dependent prostate cancer cell line was the most sensitive to the three-component mixture of black, red maca, and saw palmetto treatment. This combination provided the most abundant set of high-activity metabolites, and is worthy of consideration in further clinical applications and future in-depth study.