In vitro plant cultures are potential sources for obtaining natural products on larger scale. Callus and cell culture could not only be an alternate continuous source of proteins, but could also be a useful model system to study their regulation and biosynthesis. The leaf derived callus cultures of green and purple morphotype of O. sanctum, maintained on MS medium + 2,4-D, NAA and KN and the leaves from their respective mother explants were evaluated for the activity of antioxidant enzymes. The specific activity of APOX, CAT, GPX, GST and SOD was evaluated employing standard biochemical protocols. On comparing the leaves of purple and the green morphotypes of Ocimum sanctum Linn. for antioxidative enzymes, the purple morphotype was found to be a rich source. When their leaves were cultured and their callus maintained on MS medium, the expression of these enzymes increased significantly in vitro for both the plants. The increase in the activity may be due to abiotic stress faced by the callus under artificial conditions. The in vitro raised callus of both the plants show higher expression of APOX, GPX and SOD, while the activity of CAT and GST was reported to be higher in the in vivo leaves. To overcome oxidative stress related disorders, Ocimum sanctum particularly the purple morphotype can be used as an alternative to the commonly used green morphotype in the herbal drug industry. Besides, the callus cultures of both the plants can be exploited for commercial production of these enzymes on large scale.
