Response Surface Optimization for Investigating Antioxidant Potential of Camellia Sinensis and Withania Somnifera in Synergistic Manner

The paper highlights the synergistic potential of the novel combination of Camellia sinensis (Kangra green tea) and Withania somnifera (Ashwagandha). One variable at a time approach was used to find antioxidant potential of C. sinensis and W. somnifera alone and in combination. Optimization of antioxidant potential was done by using different plant concentrations of C. sinensis and W. somnifera using a statistical approach of central composite design (CCD) of RSM (response surface methodology). Initial antioxidant activity during optimization of the solvent system was observed in methanol for C. sinensis with DPPH, superoxide radical scavenging assay and hydrogen peroxide scavenging assay (44.9 ± 0.62, 43.77 ± 0.10, 43.88 ± 0.10% scavenging) and for W. somnifera (40.22 ± 0.39, 43.29 ± 1.12, 41.88 ± 0.11% scavenging), respectively. Initially, IC(50) has been calculated for C. sinensis (235.26 ± 0.012 μg/mL) and W. somnifera (256.39 ± 0.43 μg/mL) in methanol. Before statistical optimization, the maximum synergistic antioxidant potential of C. sinensis (200 μg/mL) and W. somnifera (150 μg/mL) with DPPH assay, superoxide radical scavenging and hydrogen peroxide scavenging assay was found to be 56.57 ± 0.62, 56.99 ± 0.42, 55.44 ± 0.53% scavenging, respectively. IC(50) value has been calculated for C. sinensis + W. somnifera (IC(50) = 215.47 ± 0.06 μg/mL). Optimization of plant concentration using CCD of RSM resulted in enhancement of antioxidant potential of C. sinensis (200.5 μg/mL) and W. somnifera (200.5 μg/mL) was found to be 78.01 ± 0.01% scavenging when compared to the initial antioxidant potential, i.e., 56.57 ± 0.62% scavenging shows a 1.37-fold increase from initial antioxidant potential. Research unveils that using various combination of C. sinensis and W. somnifera enhance the antioxidant potential in vitro. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40011-022-01423-6.