Supercritical fluid extraction of swietenia mahagoni seed: antioxidant and antimicrobial activities

Abstract

Swietenia mahagoni seeds have been used as folk medicine for a treatment of hypertension, malaria and diabetes. This research was conducted to obtain extracts from the Swietenia mahagoni using supercritical fluid extraction (SFE) with pure CO2 solvent, in order to evaluate the high- pressure method in terms of process yield and biological activity. The various conditions namely flow rate of CO2 were set up at 2, 3, and 4 ml/min; at constant pressures (P) and temperature (T). The sample extracts obtained by SFE with CO2 flow rate of 4 ml/min showed the highest percentage yield (19.67%) compared to the others. The antioxidant potential of the extracts was evaluated by the DPPH method and Folin- Ciocalteu method. The solvent flow rate of 2 ml/min gave the lowest percentage of yield, but good results in antioxidant activity and total phenolic content. The antimicrobial activity of the extracts against Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative (Escherichia coli) was evaluated based on the inhibition zone using disc diffusion assay. These results ensured that Swietenia mahagoni seed extract had inhibitory effects on the growth of Bacillus subtilis, Staphylococcus aureus and Escherichia coli at concentration of 100 mg/ml.