Another compound with immunomodulatory properties is curcumin (1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), extracted from the plant Curcuma longa. South et al. (1997) found that dietary curcumin at 40 mg/kg, fed for 5 wk, enhanced plasma IgG concentrations in rats. Churchill et al. (2000) found that mice fed 1 g of curcumin/kg of feed
had increased mucosal CD4+ T cells and B cells in the intestine, indicating curcumin can modulate lymphocyte mediated immune functions.