GENETIC RESOURCES AND CROP EVOLUTION, 2024 (SCI-Expanded)
The search for natural antioxidants to safeguard against several diseases is expanding rapidly. Interestingly, the levels of antioxidants have been discovered to be greater in the in vitro-raised calli than the plant extracts in vivo. The aim of this research was to standardize the protocols for culturing calli of five potential medicinal herbs and determine their antioxidant and polyphenolic compounds. The calli of carnation, goji berry, harmal, bitter cucumber, and datura were developed from young leaves using Murashige and Skoog media with varied forms and concentrations of cytokinin and auxin in combination after their optimization. Goji berry, carnation, and datura initiated callus in 13 days, faster than bitter cucumber (20 days). Datura had a 28.7% higher callus induction rate than bitter cucumber. The callus weight of goji berry was three times higher than harmal, with a 25.4% greater diameter than bitter cucumber. The callus of goji berry had 4.3 times more phenolic and ascorbic content than datura and 1.9x more than harmal. The callus of datura had twice the total antioxidant capacity of harmal. The callus of goji berry exhibited 5.7% increased radical-scavenging activities than datura. The enzyme activities of catalase and superoxide dismutase were 2.6% and 2.4% greater in the callus of goji berry than datura. The callus of goji berry also had 2.1% and 2.4% increased peroxidase and ascorbate peroxidase activities than datura and bitter cucumber, respectively. From the findings, it can be concluded that the callus of goji berry is a highly promising source of natural antioxidants, exhibiting significantly higher levels of antioxidant and polyphenolic compounds compared to other medicinal herbs.