Anthocyanins are extensively studied for their health-related properties, including antibacterial activity against urinary tract infections (UTI). Among common fruits, blueberries, with their remarkable antioxidant capacity, are one of the richest sources. Anthocyanin-rich extracts were obtained from four varieties: Snowchaser, Star, Stella Blue and Cristina Blue, grown in the hot climate of Southern Spain. Their total anthocyanins contents (TAC) were determined spectrophotometrically, and the anthocyanin profile by ultra high performance liquid chromatography - tandem mass spectrometer (UHPLC-MS/MS). Their antioxidant activity was assessed by oxygen radical absorbance capacity (ORAC) assay, while antibacterial activity against strains isolated from UTI patients was assessed in vitro, helping to select the varieties with the highest bioactive potential. Star showed the highest TAC and antioxidant activity (1663 ± 159 mg of cyanidin-3-O-glucoside (cy-3-O-glu) equivalents/100 g fresh weight (FW), 6345 ± 601 μmol Trolox equivalents (TE)/100 g FW, respectively), followed by Cristina Blue, Stella Blue and Snowchaser. As far as we know, this is the first time that cyanidin-3-rutinoside has been identified in blueberries. The extracts inhibited all the tested strains, MICs ranging from 0.4 mg/mL (for Stella Blue extract against UTI P. aeruginosa) to 9.5 mg/mL (for all extracts against UTI K. pneumoniae ssp. pneumoniae). This is the first study that assessed in vitro the antibacterial activity of blueberries against Klebsiella pneumoniae, Providencia stuartii and Micrococcus spp. strains isolated from UTI.

中文翻译：

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在炎热气候下种植的蓝莓中的花色苷具有很强的抗氧化活性，可能对尿道细菌有效。

花色苷因其与健康有关的特性而被广泛研究，包括对尿路感染（UTI）的抗菌活性。在普通水果中，蓝莓具有卓越的抗氧化能力，是最丰富的来源之一。富含花青素的提取物来自四个品种：追逐者，星，斯特拉蓝和克里斯蒂娜蓝，它们在西班牙南部炎热的气候中生长。分光光度法测定其总花色苷含量（TAC），并通过超高效液相色谱-串联质谱仪（UHPLC-MS / MS）测定花色苷分布。通过氧自由基吸收能力（ORAC）分析评估了它们的抗氧化活性，而在体外评估了对从UTI患者中分离出的菌株的抗菌活性，帮助选择具有最高生物活性的品种。Star显示出最高的TAC和抗氧化活性（1663±159 mg花青素-3-O-葡萄糖苷（cy-3- O -glu）当量/ 100 g新鲜重量（FW），分别为6345±601μmolTrolox当量（TE）/ 100 g FW），其次是Cristina Blue，Stella Blue和Snowchaser。据我们所知，这是蓝莓中花青素-3-芸香糖苷的首次鉴定。提取物抑制所有测试的菌株，MIC范围从0.4 mg / mL（对于对抗UTI铜绿假单胞菌的Stella Blue提取物）到9.5 mg / mL（对于针对UTI肺炎克雷伯氏菌ssp。肺炎的所有提取物）。这是第一项体外评估蓝莓对肺炎克雷伯菌，斯图亚特氏菌和微球菌的抗菌活性的研究。spp。从UTI分离的菌株。