GC-MS Analysis and Antioxidant Activity of Bauhinia nakhonphanomensis Leaf Ethanolic Extract

Context: Bauhinia nakhonphanomensis Chatan. A new species that is endemic to Thailand. Aims: Leaves of B. nakhonphanomensis were extracted and the extract was used in gas chromatography-mass spectrometry (GC-MS) analysis to evaluate the total phenols, total flavonoids and antioxidant activity. Methods: The extract of B. nakhonphanomensis was analyzed by GC-MS. Quantitative analysis for total phenols was done by the Folin-Ciocatteu method and for total flavonoids by the aluminium chloride method. The antioxidant activity of the ethanolic extract was evaluated by the DPPH method. Results: GC-MS analysis revealed the presence of 19 phytochemical constituents. These compounds were identified by comparing their retention times and peak areas with those from the literature and by interpretation of the mass spectra. The major chemical constituents were inositol (48.55 %), alpha-tocopherol (12.21 %) and phenol (6.61 %). Total phenolic content was 48.69±0.56 mg/100 of Gallic acid equivalent (GE). The total flavonoid contentwas 10539± 6.14 mg/100 of quercetin equivalent (QE). Antioxidant activity was 17.07±0.24 μg/100 of ascorbic acid equivalent antioxidant capacity (AEAC).Conclusion: These findings are the first report and suggest that the rich phytochemical content of B. nakhonphanomensis has good antioxidant activity.