Trans-resveratrol Extraction in Four Brazilian Arachis hypogea L. Cultivars with Microwave-Assisted Extraction: Optimization with Response Surface Methodology and Comparison with Conventional Maceration

Peanut (Arachis hypogaea L.) is the fourth most consumed oleaginous in the world, producing highly energetic seeds, rich in lipids, proteins, vitamins and carbohydrates. Several bioactive constituents and pharmacological activities have already been observed in extracts of roots, leaves and seeds, including resveratrol. In this work, we report a study of two extraction methodologies, conventional maceration and microwave-assisted extraction (MAE) for the extraction of trans-resveratrol. Parameters that affect the efficiency of microwave-assisted extraction of trans-resveratrol from aerial parts of A. hypogaea were optimized adopting the response surface methodology mathematical experimental designs. The contents of different organs of four Brazilian important cultivars (IAC 886, IAC Caiapó, Tatu ST IAC, and IAC 8112) were evaluated by HPLC. Microwave-assisted extraction, with the use of 37 mL of solvent per gram of dry tissue, 1200 g agitation for 15 minutes at 37°C, proved to be more efficient than conventional maceration extraction. Root extracts from IAC Tatu prepared with this methodology showed the highest trans-resveratrol content (1.371 ± 0.07 mg/g extract) among the cultivars tested.