Preparation of extracts Air-dried leaves were packed into a soxhlet apparatus and extracted sequentially with petroleum ether (PE), benzene (BZ), chloroform (CF), ethanol (EA) and water (AQ). The organic extracts were dried in vacuum desiccator and the solvents were removed in vacuum (40°C). The extracts were dissolved in Di methylsulphoxide (DMSO), ethanol or H2O prior to analysis depending upon their solubility. The extracts were subjected to further analysis and all the assays were done in triplicates. Phytochemical analysis The extracts were tested by different tests to determine the presence of various phytochemicals: Wagner for alkaloids, Foam test for Saponins and Ferric chloride, gelatin and Lead acetate for the presence of phenolic compounds and flavonoids. (Harborne, 1998) Determination of Total Phenolics The total phenolic content (TPC) of different extracts of A. nilotica was determined by the method of Folin–Ciocalteu reaction (Kujala et al., 2000), using gallic acid as standard. To the extract, Folin–Ciocalteu reagent and Na2CO3 was added. After 20 min incubation at room temperature, the absorbance was measured at 730 nm. Determination of Total Flavonoids The total flavonoid content (TFC) of the different extracts of A. nilotica was determined by slightly modified method (Nieva Moreno et al., 2000). To the extract, potassium acetate and aluminium nitrate were added. After 40 min incubation at room temperature, the absorbance was measured at 415 nm using quercetin as standard. 1,1-Diphenyl-2-Picrylhydrazyl Free Radical Scavenging Activity (DPPH) The ability of the extract to scavenge DPPH radicals was assessed as described by Ohinishi et al. (1994). To different concentrations of extract, 3 ml of freshly prepared ethanolic DPPH (0.1 mmol/ l) solution was added. After 30 minutes of incubation in dark, the absorbance was recorded at 517 nm. Results were expressed as percentage inhibition of DPPH. % Inhibition = (Abscontrol _ Abssample)/Abscontrol) x 100 The percentage inhibition was plotted against the sample extract concentration in order to calculate the IC50 values, which is the concentration (μg/ml) of extract that causes 50% loss of DPPH activity. Results were compared with the positive control, ascorbic acid. Statistical analysis All experiments were repeated at least three times. Results were reported as Mean ±SE. The statistical significance between antioxidant activity values of the extracts was evaluated with one way ANOVA between the groups followed by Holm-Sidaktest.P values less than 0.05 were considered statistically significant. III. RESULTS Ethanobotanicals of unexplored plants Ethanobotanical usage of unexplored plants namely Acacia nilotica sub sp. Indica, Allium stracheyi and Naravelia zeylanica were collected from Malayali, Bhotiya and Muthuvan tribes respectively (Table 1). About 1,500 plants with varied medicinal uses are mentioned in the ancient texts with around 800 plants being used in the traditional medicine systems (Kamboj, 2000). Several works talk of an available link between both ancient and traditional medicine in India and elsewhere the forests and the Proceedings of the International Conference on Climate Change, Biodiversity and Ecosystem Services for the 109 Sustainable Development Goals (SDGs): Policy and Practice 27-29 June 2016, Cha-am, Phetchaburi, Thailand
Proceedings of International Conference on Climate Change, Biodiversity and Ecosystem Services for the Sustainable Development Goals : Policy and Practice 27-29 June 2016 at the Sirindhorn International Environmental Park, Cha-am, Phetchaburi, Thailand
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