Immunomodulatory Potentials of Winged Bean (Psophocarpus tetragonolobus) Bioactive Compounds on Human Lymphocyte Proliferation

Abstract

Winged bean (Psophocarpus tetragonolobus) has been reported to consist of many bioactive compounds that can improve the human immune system. Food preparation using heat treatment applied typically can change the bioactive properties of the bean. These studies' main aims were to analyze antioxidants activity and immunomodulatory effect of young winged bean pods and mature winged beans, boiled or canned on human lymphocytes, representing the immune system. The samples were extracted using three-stage maceration methods with n-hexane, ethyl acetate, and water. The extracts were cultured with lymphocyte cells using various concentrations representing normal consumption. IL-2 representing cell proliferation was analyzed using ELISA. Cell marker proteins CD4+, CD8+, CD3+, CD19, and CD16/56 were analyzed using a flow cytometer. The highest antioxidants activity was on the water extract of raw mature bean (7.2175±0.4794 mg AAE/g). The boiling process increased young winged bean anti-oxidant activity (P<0.05), but decreases the anti-oxidant activity of the mature bean (P<0.05). The highest proliferation indexes were obtained from water extracts of both boiled (2.13) and canned mature bean (2.12). Water extracts of all samples increased expressions of IL-2, CD4+, CD8+, CD3+, CD19 and CD16/56 on the cell surface. Boiled young winged bean pods have the best activity in increasing CD19 marker. Canned mature bean was effective in increasing CD16/56 expression. Boiling and canning of both young and mature winged beans can increase the immune system as shown by the immune parameter analyzed.