Ten known phenolic compounds including [4]-gingerol (1), [6]-gingerol (2), [10]-gingerol (3), (3S,5S)-3,5-dihydroxy-1-(4-hydroxy-3-methoxyphenyl) decane (4), (3R,5S) -3, 5-dihydroxy-1-(4-hydroxy-3-methoxyphenyl) decane (5), [6]-shogaol (6), [10]-shogaol (7), gingerenone A (8), hexahydrocurcumin (9),