Three iridoids (lamalbid (I1), sesamoside (I2) and shanzhiside methyl ester (I3)) and seven polyphenols (cistanoside F (P1), chlorogenic acid (P2), pedalitin-6-O-laminaribioside (P3), pedaliin (P4), isoacteoside (P6), pedalitin (P7) and martynoside (P8)) were identified in young sesame leaves