Characterization of quercetin derivatives in a crossing combination of Habanero white and Capsicum annuum peppers and evaluation of the encapsulation efficiency of peppers extract in liposomes by LC-MS/MS

Common peppers (Capsicum) are an important source of phytochemicals, including polyphenols, flavonoids and bioactive capsaicinoids [1]. Capsaicinoids are responsible for the hot, spicy flavour presented by chilli peppers. Due to the broad range of biological activities (antioxidant, anti-inflammatory, antimicrobic, anticancer, cardioprotective) covered by Capsicum metabolites, many peppers-based nutraceutical products are available on the market [2]. Recently, novel delivery systems for enhancing the oral bioavailability of bioactive molecules are being evaluated, such as liposomes, micelles, micro/nano-emulsions, colloidal capsules and solid nanoparticles [3]. In this study, we investigated the liposomal encapsulation of a methanolic extract of white chilli peppers, obtained from an original crossing combination between Capsicum chinense (also known as Habanero white) and Capsicum annum species. An LC-MS/MS method was developed to conduct a preliminary screening of the metabolic profile of the white peppers. In addition to capsaicinoids, a deep qualitative profile of the quercetin derivatives was provided. Nine glycoconjugates were identified, i.e. quercetin-6-C-hexoside-8-C-pentoside/apioside, quercetin-4′-rhamnoside-7-hexoside, quercetin 7-O-pentoside/apioside, quercetin-3-O-pentosyl/apiosyl-rhamnosyl-hexoside, quercetin 7-O-glucoside, quercetin-3-O-rhamnoside-7-O-hexoside, quercetin-3-O-rutinose, quercetin 7-O-rhamnoside and quercetin rhamnoside-(feruloyl-hexoside). The developed LC-MS/MS method was applied to quantify the liposomial encapsulation efficiency of the white peppers extract. High encapsulation efficiency values were obtained