In this study, leaves and stems of Talinum triangulare were sequentially extracted with
phosphate buffer solution to obtain PTL and PTS (phosphate buffered extracts of T. triangulare
leaves and stems), with 75% ethanol to obtained ETL and ETS (ethanol extracts of T.
triangulare leaves and stems), or with 90C boiling water to obtain WTL and WTS (water
extracts of T. triangulare leaves and stems). We investigated the antioxidant activities of
various T. triangulare extracts, analyzed the extracts' stimulations on human mononuclear
cell (MNC) growth and secretion of cytokines (interleukin-1 beta, interferon-g, and tumor
necrosis factor-a) and nitric oxide, and then assayed their subsequent inhibitions on human
leukemic U937 cell growth. Results indicated that extracts of T. triangulare showed significant
antioxidant activities. Among these extracts, WTS showed the highest stimulatory effect on
human MNC growth. The secretion levels of interleukin-1 beta, interferon-g, and tumor
necrosis factor-a in the conditioned medium, wherein human MNC was treated with 500 mg/
mL WTS for 72 hours, were 1275, 859, and 2222 pg/mL, respectively. All conditioned media
obtained from human MNCs cultured with various T. triangulare extracts showed significant
inhibition against U937 cell growth of over 40%. These results suggest that T. triangulare
extracts may be used in health foods for their immunomodulatory potential.