Bioactive compounds and antioxidant capacity of Lonicera caerulea berries: Comparison of seven cultivars over three harvesting years

This study aimed at characterization of bioactive compounds of haskap berries (Lonicera caerulea L.) cultivated in Switzerland and their antioxidant capacity. Seven cultivars i.e. 'Berry Smart Blue', 'Indigo Gem', 'Indigo Treat', 'Morena', 'Tundra', 'Uspiech' and 'Viola' were compared over three harvesting years. Cyanidin-3-glucoside was the main anthocyanin found in haskap berries and at the same time the predominant phenolic compound identified, its content varied between 12.5 and 87.5 mg/g of dry matter. 'Morena', 'Indigo Treat' and 'Uspiech' cultivars emerged as rich in total polyphenols, total anthocyanins and antioxidant capacity. The content of individual polyphenols was the highest in 'Indigo Treat' berries. Ascorbic acid content was in the range of 1.78-4.21 mg/g DM. It was the highest in 'Indigo Gem' and 'Indigo Treat' cultivars. Sugars were more concentrated in 'Indigo Gem', 'Indigo Treat' and 'Viola'. The significant differences in bioactive content between different harvesting years evoked by different weather conditions were noted. 'Indigo Treat' cultivar deserves further attention as potentially well adapted for further cultivation in Switzerland and providing berries rich in bioactive compounds, which might be of interest to the consumers concerned about health promoting properties of their diet.