Antioxidant activity, total anthocyanins, phenols and flavonoids Contents were monitored in a callus induced from stem segment culture of sweetpotato (Ipomoea batatas L.) Abees, the Egyptian orange-fleshed cultivar in addition to four genotypes (199062.1-1999026.1-199015.14- 199004.2) obtained from the International Potato Centre (CIP). In vitro callus culture were grown over period of four weeks in dark on Murashige and Skoog (MS) medium supplemented with different concentrations of osmotic potential induced by (0.03, 0.1, 0.15 molar) sucrose or sorbitol, MS medium without any sugar used as a control. It was found that the dominant DPPH radical-scavengers of Abees cultivar was due to the presence of anthocyanins and phenolic compounds rather than flavonoides, while at 199062.1 was as a consequence of flavonoids and at 199004.2 was a result of the phenolic compounds. Anthocyanins and flavonoids accumulation stimulated by increasing the sugar concentration up to 0.1 M and 0.15 M respectively using sucrose; however phenol compounds increased in 0.1 M sorbitol. Radical-scavenging activity contributors varied according to the cultivar and the osmotic potential.