Phytochemical screening and antioxidant property of Solanum nigrum L. and Stenochlaena palustris (Burm. Fil.) Bedd from Keningau, Sabah / Debora Jolian

The Stenochlaena palustris, from the family of Blechnaceae and Solanum nigrum, from the family of Solanaceae are used as vegetables and traditional medicine in Sabah. They ar.e both well known for their therapeutic properties. Present investigation was undertaken to evaluate the possible antioxidant potential of ethanol and acetone extract of fresh and dried sample of Stenochlaena palustris and Solanum nigrum. The aim of this study was to assess the antioxidant activity of ethanol and acetone extract using 1,1 ,diphenyl-2,picrylhydrazyl (DPPH) free radical scavenging activity. The phytochemical compounds in plants were detected by using standard procedure where particular chemicals were used and colour changes were observed. The results from phytochemical screening analysis have shown that alkaloids are detected in both sample extract of Solanum nigrum and Stenochlaena palustris whereas terpenoid only detected in the dried sample of Solanum nigrum. As for the phenol and flavonoid it only detected in the dried Solanum nigrum and both in sample extract of Stenochlaena palustris. As for the saponin and tannins they are all presence in both sample extract of Solanum nigrum but not in sample extract of Stenochlaena palustris which used the acetone as solvents extract. The cardiac glycosides compound are only found in Solanum nigrum. Hence, it means that the potential for both dried and fresh sample to have antioxidant properties were the same. The highest result of percentage of inhibition if compared with the others samples was recorded in dried ethanolic extract of Solanum nigrum where at 300 mg/ml the inhibition percentage was 74.74 % (± = 0.00055). The lowest for percentage of inhibition compared with other samples was recorded in fresh ethanolic extract of Solanum nigrum where at 50 mg/ml the inhibition percentage was 44.05 % (± = 0.00064) respectively. It can be concluded that dried ethanolic extract of Solanum nigrum was the most effective to inhibit free radical oxidant. Further study is needed to evaluate the bioactivity of both Solanum nigrum and Stenochlaena palustris especially in antioxidant activity.