Extraction yield, phenolics content, and antioxidant activities of the materials extracted conventionally and/or ultrasonically from Bene hull by a number of aqueous and organic solvents were investigated. Higher extraction yields in general were obtained by the less polar solvents (12.1–47.5%). Polar protic solvents exhibited the highest content of total phenolics extracted (110–150 mg/g), followed by polar aprotic (30.0–43.5 mg/g) and non-polar solvents (3.3–5.2 mg/g). Good correlation (R2 = 0.9721) was obtained between the DPPH radical-scavenging activities and total phenolics contents. Many similarities were observed between the results of the DPPH (EC50 = 0.6–1105.3 lg/ml) and FRAP (0.1–8.5 mmol/g) assays. The highest oxidative stability index (OSI) value belonged to the methanol and water extracts, respectively. All the extraction factors significantly improved by 30 min sonication, especially in polar protic solvents. A 10-min sonication in water extraction could provide the same achievements as those of the 24-h conventional method.

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