Figure 1: Graphical abstract. The active ingredients of Yam include polysaccharides, proteins,allantoin,starch, diosgenin, and phenolic compounds.. It has pharmacological effects such as antioxidant activity, immunomodulatory activity, antitumor activity, blood lipid and glucose control,modulating intestinal microbiota and estrogenic activity

Figure 2: Chemical structures of phenolic compounds.
(1) tristin. (2) 2',3,5-trihydroxybibenzyl. (3) 3,3',5-trihydroxy-2'-methoxybibenzyl. (4) batatasin III. (5) batatasin IV. (6) 2',4-dihydroxy-3,5-dihydroxy-4-methoxybibenzyl. (7) 3,5-dimethoxy-2'-hydroxybibenzyl. (8) 3,5-dimethoxybibenzyl. (9) 3,4-dimethoxy-2',5-dihydroxybibenzyl. (10) batatasin V. (11) 3,5-dimethoxy-2,7-phenanthrenediol. (12) batatasin I. (13) hircinol. (14) 2,5-dihydroxy-7-methoxy-9,10-dihydrophenanthrene. (15) 9,10-dihydro-dibenzoxepin-2,4-diol. (16) 9,10-dihydro-4-methoxy-dibenzoxepin-2-ol. (17) p-hydroxyphenylethyl pcoumarate. (18) p-hydroxyphenethyl trans-ferulate. (19) (1E,4E,6E)-1,7-bis(4-hydroxyphenyl)-1,4,6-heptatrien-3-one. (20) (4E,6E)-1,7-bis(4- hydroxyphenyl)-4,6-heptadien-3-one. (21) (4E,6E)-7-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)-4,6-heptadien-3-one. (22) two phydroxyphenylethyl-p-hydroxyphenyl propenoic acids, (3R,5R)-3,5-dihydroxy-1,7-bis(4-hydroxyphenyl)-3,5-heptanediol. (23) (3R,5R)-1,7- bis(4-hydroxy-3-methoxyphenyl)-3,5-heptanediol [81].