Exploring the Antioxidant, Antidiabetic, and Antimicrobial Capacity of Phenolics from Blueberries and Sweet Cherries

Abstract

(1) Background: Nowadays, special attention has been paid to red and purple fruits, including blueberries and sweet cherries, since they are highly attractive to consumers due to their organoleptic properties, standing out due to their vibrant red and purple colours and sweet flavour, and nutritional value. (2) Methods: The present study evaluated the phenolic profile of phenolic-enriched extracts from blueberries and sweet cherries and explored their antioxidant potential against DPPH, superoxide and nitric oxide radicals, and ferric species, and their potential to inhibit the α-glucosidase enzyme. Furthermore, their antimicrobial activity was also determined by microdilution method against four Gram-positive strains (Enterococcus faecalis ATCC 29212, Bacillus cereus ATCC 11778, Listeria monocytogenes LMG 16779, and Staphylococcus aureus ATCC 25923) and five Gram-negative strains (Salmonella enterica subsp. enterica ATCC 13311 serovar Typhimurium, Klebsiella pneumoniae ATCC 13883, Proteus mirabilis CECT 170, Serratia marcescens CECT 159, and Acinetobacter baumannii LMG 1025). (3) Results: By chromatographic techniques, eight anthocyanins were detected in blueberry coloured fraction and total extract, and five anthocyanins were detected in sweet cherry total extract and coloured fraction, while quercetin aglycone and chlorogenic acids were the dominant non-coloured compounds in blueberries and sweet cherries, respectively. All extracts demonstrated significant antioxidant properties, as well as the ability to inhibit the activity of α-glucosidase enzyme and the development of various microorganisms. (4) Conclusion: The obtained data evidence the promising biological potential of blueberries and sweet cherries, being highly correlated with the presence of phenolic compounds.

The Effect of Phenolic-Rich Extracts of Rubus fruticosus, R. ulmifolius and Morus nigra on Oxidative Stress and Caco-2 Inhibition Growth

“…The presence of Cy 3-O-dioxalylglucoside, Cy 3,5-diglucoside, and Pg3Rut in R. fruticosus is in accordance with other studies, as is the presence of Cy3Gluc and Pn3Gluc in R. fruticosus and M. nigra [3,16]. Comparing with other red fruits, blueberries present other anthocyanins not detected in these berries, namely Dp 3-O-arabinoside (2147.51-4444.20 µg/g dw), Pt 3-O-galactoside (3609.50-19,654.66 µg/g dw), and malvidin 3-O-arabinoside (2249.05-3020.86 µg/g dw) [27], while sweet cherry phenolic extracts showed considerable amounts of Cy3Rut (3865.64 µg/g dw) and Pg3Rut (337.46 µg/g dw) [18].…”

“…Focusing on R. fruticosus, Polish blackberry n-hexane, carbon dioxide, and ethanol ex-tracts showed IC 50 scores of 2.47, 14.22, and 1223.84 µmol TE/g, respectively [41]. When compared to other red fruits, the investigated extracts were more efficient than blueberry extracts (IC 50 values from 144.68 to 208.06 µg/mL) [27].…”

“…In contrast with other small fruits, phenolic-rich extracts from sweet cherries present higher amounts of phenolic acids (with a total of non-coloured phenolics of 11,034.15 µg/g dw), representing about 69.8% of their total phenolic compounds [18], while Q aglycone was the main one detected in phenolic-rich blueberries (6962.43-7521.47 µg/g dw) [27].…”

“…Relatively to other red fruits, the capacity to reduce • NO was stronger than that of Sweetheart cherry phenolic-rich extract (IC 50 = 358.64 ± 2.40 µg/mL dw) [27]. On the other hand, Saco sweet cherry extracts demonstrated superior activity (IC 50 = 33.72 ± 0.89 µg/mL dw) [18].…”

Potential Role of Dietary Phenolic Compounds in the Prevention and Treatment of Rheumatoid Arthritis: Current Reports

“…Focusing on individual compounds from honey, high correlations were found between caffeoyl hexose, quercetin 7-glucoside-3-O-rutinoside, quercetin derivative, and quercetin acetyl rhamnoside and • NO scavenging potential (r > 0.7581), and concerning quercetin 3-O-rutinoside and hemoglobin oxidation, hemolysis and lipid peroxidation (r > 0.7355). Additionally, positive correlations were also reported between caffeoyl hexose and quercetin acetyl rhamnoside and lipid peroxidation (r = 0.7352 and r = 0.755, respectively) [206], whereas a mild correlation (r = 0.64) between the quercetin content of pollen extracts and protective effects against oxidative injury induced by AAPH on Hepa1-6 hepatic cells was also reported [208]. On the other hand, strong correlations were found involving quercetin 3-O-glucoside (r = 0.8640) and ρ-coumaric acid derivative 1 (r = 0.9444), ρ-coumaroylquinic (r = 0.8646), ρ-coumaric (r = 0.8012), and 5-O-caffeoylquinic (r = 0.9907) acids in sweet cherries and the nitric oxide scavenging test, and also involving this last hydroxycinnamic and superoxide radical (r = 0.9958) [180,209] as well as between malvidin, delphinidin 3-O-arabinoside, and 5-O-caffeoylquinic acid and the antioxidant potential shown by blueberry fruits (r > 0.8689) [209].…”