Possible antitumor promoters in Spinacia oleracea (spinach) and comparison of their contents among cultivars.

Spinach leaves were found to contain two potent antitumor promoters as detected by the activity against tumor promoter-induced Epstein-Barr virus activation. The active components were identified as 1-O-alpha-linolenoyl-2-O-(7Z,10Z,13Z)-hexadecatrienoyl-3-O-beta-D-galactopyranosyl-sn-glycerol and 1,2-di-O-alpha-linolenoyl-3-O-beta-D-galactopyranosyl-sn-glycerol by spectroscopic data and some chemical and enzymatic reactions. Their contents significantly varied with the cultivar and with the culture conditions.