Main Article Content
The aim of this research was to study appropriate extraction methods and conditions of antioxidant compounds from longan seed by comparing 3 methods; i.e. maceration, reflux and magneto pulse extraction. The different extraction times were studies at 3, 5 and 7 days for maceration, 1, 3 and 6 hours for reflux and 15, 30 and 45 minutes for pulsed electric field extraction. The extracts were evaluated for their antioxidant activity and total phenolic contents. The reflux extract for 6 hours showed the highest total phenolic content and antioxidant activity, followed by the reflux extract for 3 hours and the pulsed electric field extract for 45 minutes, respectively. Therefore, the reflux extraction for 6 hours is the suitable method and condition for antioxidant compounds extraction from longan seed. This condition gave the total phenolic content of 271.33±6.11 mg GAE/g dry extract and possessed the antioxidant activity by DPPH assays with the IC50 value of 36.9±0.4 μg/mL; FRAP value of 1,010.42±8.59 μmol FeSO4/g dry extract.
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