Bioactive Compounds in the Residue Obtained from Fruits of Some Cultivars of Lonicera caerulea

This paper aimed to investigate the bioactive compounds in the dry powder residue of honeysuckle cultivars after extracting the juice. Based on the analyses performed on the total content of phenolic compounds, flavonoids, anthocyanins, tannins, carotenoids and vitamin C, the results indicated that dried Lonicera caerulea residue represented a rich source of phenolic compounds (8041.36 mg GAE 100 g−1), of which about 80% were tannins (6432.10 mg GAE 100 g−1). The flavonoid content varied around 2436.95 mg CE 100 g−1. Vitamin C (185 mg 100 g−1), lycopene and β-carotene (over 2.5 and 2.8 mg 100 g−1, respectively) were also quantified. Among the phenolic acids, chlorogenic acid predominated (316 mg 100 g−1), followed by cryptochlorogenic acid (135 mg 100 g−1) and neochlorogenic acid (32 mg 100 g−1). Flavonoids were mainly represented by catechin (2594 mg 100 g−1) and anthocyanins (1442 mg 100 g−1). Similar amounts of epicatechin and rutin were measured (156 mg 100 g−1 and 148 mg 100 g−1), while the isoquercetin concentration was below 15 mg 100 g−1. In conclusion, the high level of phytocompounds and the diverse composition of dry Lonicera caerulea residue support its high nutraceutical value and high health-promoting potential.