Antioxidant and anti-glycation potential of green pepper (Piper nigrum): Optimization of β-cyclodextrin-based extraction by response surface methodology

Abstract

Green pepper (Piper nigrum) presents high levels of functional compounds, with antioxidant and anti-glycation properties. Thus, the optimization of the β-cyclodextrin-based extraction of functional compounds from green pepper through Response Surface Methodology was performed. The optimum extraction conditions were assessed by optimizing total polyphenolic content (TPC) and antioxidant activity (DPPH• and FRAP methods). 15 mM for β-CD solution, 5 min of ultrasonication and 41 °C were the optimum extraction conditions, with the TPC of 24.9 mg GAE/mL and the anti-radical activities were 3.1 mg GAE/mL (DPPH• assay) and 0.45 mg GAE/mL (FRAP method). This natural extract obtained through eco-friendly techniques proved to be effective to reduce the formation of hydroxymethylfurfural, a glycation marker, at 70 and 80 °C. GPE presented higher TPC than black and white pepper. The relationship between the antioxidant and anti-glycation properties was confirmed and green pepper and can be proposed as a natural potential anti-glycation agent.

Keywords: 2,2-Diphenyl-1-picrylhydrazyl radical (DPPH•) (PubChem CDI 2735032); 2,4,6-Tripyridyl-s-triazine (TPTZ) (PubChem CID 77258); 5-Hydroxymethyl-2-furfural (HMF); 5-Hydroxymethyl-2-furfural (HMF) (PubChem CID 237332); Aminoguanidine (PubChem CID 2146); Anti-glycation; Antioxidant activity; Bovine serum albumin (BSA) (PubChem CID 16132389); Ferric chloride hexahydrate (PubChem CID 6093258); Gallic acid (PubChem CID 370); Glucose (PubChem CID 5793); Green pepper; Phosphate buffered saline (PBS) (PubChem CID 24978514); Polyphenols; Ultrasonic; α-Dicarbonyls; β-Cyclodextrin; β-Cyclodextrin (β-CD) (PubChem CID 444041).