Comparative analysis of the biological activities of different extracts of Nigella sativa L. seeds
Prairna Balyan, Ahmad Ali
Abstract
Plants provide an abundant supply of metabolites with a wide range of chemical structures that may have medicinal promise. This chemical diversity facilitates the discovery of novel and unusual chemical constituents with their biological properties. This study looked at preliminary phytochemical profiles and tested the antidiabetic, antioxidant, and anti-inflammatory activities of four different extract s (methanol, hexane, ethanol, and aqueous) of Nigella sativa L. seeds. Quantitative and qualitative phytochemical analysis was performed using standard methods. The antidiabetic ability was determined using -amylase and -glucosidase enzyme inhibition assays. To examine the antioxidant property in vitro, DPPH, ABTS, HRSA, and NOS assays were used. The correlation between TPC and antioxidant activity was also evaluated. Using agarose gel electrophoresis, the degree of glycoxidative DNA damage was determined. Anti-inflammatory activity was evaluated using the inhibition of albumin denaturation assay. Aqueous extract of N. sativa seeds exhibited the highest values: TPC (228.18 0.13 mg GAE/g DW), TFC (191.64 0.031 g QE/g DW), DPPH (74.62%), ABTS (49.45%), hydroxyl radical scavenging activity (63.60%), and nitric oxide scavenging activity (79.39%) as compared to the other seed extracts. The IC 50 values for the extracts in the -amylase and -glucosidase assays were in the range of 1.07 mg/ml to 2.97 mg/ml, respectively. Also, there was a significant correlation between TPC and antioxidant activities. Inhibition of protein denaturation was 43.30%, 28.68%, 35.98%, and 57.56% in the methanolic, hexane, ethanolic, and aqueous extracts of N. sativa seeds, respectively, compared to aspirin (68.74%) at 1 mg/ml. Furthermore, the presence of extracts had a substantial antioxidant effect, protecting DNA against the oxidative stress agent, H 2 O 2 . From the results, it is concluded that the phytochemicals present in the N. sativa extracts may be responsible for the antioxidant, antidiabetic, and anti-inflammatory activities. This discovery provides a sufficient scientific framework to isolate and purify bioactive molecules for future applications.