Background and aim: Cloudberries are a rich source of phenolics, mainly ellagitannins (ETs) and ellagic acid (EA), which have recently been associated with human health benefits. Our aim is to induce changes in cloudberry phenolic composition based on microbial fermentations with different lactic acid bacteria (LAB) and evaluate the antimicrobial and antioxidant properties. Materials and Methods: Cloudberry fermentations were carried out with different strains such as, Lactobacillus plantarum, Lactococcus lactis, Leuconostoc citreum and Pediococcus pentosaceus, during 7 and 14 days. The changes produced in the phenolic profiles were analyzed by HPLC-DAD. Additionally, we also have examined the antimicrobial activity of these berry fermentations against Staphylococcus aureus and Escherichia coli and yeast, Candida albicans and antioxidant activity by DPPH assay. Results: HPLC-DAD analysis showed changes in the phenolic composition of fermented berry samples. All LAB used increased the EA content up to 5-fold when compared to the starting point. In addition, an EA-conjugate was detected after seven days of fermentation and it increased after fourteen days (2-4 mg/g dry-weight). In contrast, ETs present in cloudberry extracts were decreased. These changes could be explained by the hydrolysis of ETs during fermentation, which liberated EA. Other phenolic compounds, as quercetin-3-O-hexoside (0.3-0.4 mg/g dry-weight) and benzoic acid (4.1-6.8 mg/g dry-weight) were stable after 14 days of fermentation with Lb. plantarum, Lc. citreum and P. pentosaceus. The highest amount of EA was observed when cloudberry was fermented with P. pentosaceus (28 mg/g dry-weight). This fermentation, improved in EA content, also showed good antimicrobial activity against S. aureus and E. coli but no activity was seen against C. albicans. In addition, increasing trend in DPPH radical scavenging activity was detected during LAB fermentations. Conclusions: These results demonstrated that EA-enriched cloudberry material obtained after LAB fermentations has an added-value for further use in functional food products and drug development, which could exert more beneficial effects.
|Publication status||Published - 2011|
|MoE publication type||Not Eligible|
|Event||5th International Conference on Polyphenols and Health - Sitges, Spain|
Duration: 17 Oct 2011 → 20 Oct 2011
|Conference||5th International Conference on Polyphenols and Health|
|Period||17/10/11 → 20/10/11|