Determination of total phenolics and anthocyanin contents in the pericarp of hot chilli pepper (Capsicum annuum L.)
This study was aimed to determine the contents of both total phenolics and anthocyanin mainly in the pericarp part of hot chilli pepper, considerably attributing for an enzymatic browning effect. The extraction conditions for total phenolics and anthocyanin in the sample were separately investigated. Total phenolic compounds were extracted with a solvent ratio of methanol: 0.05% (v/v) aqueous HCl (90/10, v/v) prior to determination by Folin-Ciocalteu method. While anthocyanin was extracted with 2% (v/v) HCl in methanol and then cleaned up using C18 solid-phase extraction prior to analysis by HPLC-PDA. Both of the optimum extraction conditions and their determination procedures were also applied for other kinds of the chilli pepper samples. From the results, the contents of anthocyanin and total phenolics in these samples were ranged of 0.796–4.70 mg CGE kg-1 and 0.782–4.52 g GAE kg-1 fresh weight, respectively. Their contents of the dried ground samples were also determined and found to be in the range of 62.9–70.3 mg CGE kg-1 and 81.8–90.2 g GAE kg-1 dry weight, respectively. It is generally noted that the contents of total phenolics in the hot chilli peppers were relatively higher (about 103-folds) than those of anthocyanin.