Department of Veterinary Public Health, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand.
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, Bangkok 10400, Thailand.
Molecules. 2021 Mar 22;26(6):1773. doi: 10.3390/molecules26061773.
extracts from the seeds collected from Lampang and Pattani provinces in Thailand, and young fruits and flowers exhibited in vitro display antioxidant and antibacterial activities against clinically isolated zoonotic bacteria including , , , -hemolytic and . The orange crystals and yellow precipitates were obtained from the preparation processes of the seed extracts. The orange-red crystals from the seeds collected from Lampang province exhibited strong in vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging effects (EC value = 25.99 ± 3.30 μg/mL) and antibacterial effects on and -hemolytic while the yellow precipitate from the same source exhibited only antioxidant activity. Quantitative analysis of phytochemicals in samples by spectrophotometric and HPLC techniques showed that they contained different amounts of total phenolic, total flavonoid and three major flavones; baicalin, baicalein and chrysin contents. Young fruit extract, which contained low amounts of flavone contents, still promoted antibacterial effects against the tested bacteria with IC values lower than 1 mg/mL and MIC values between 4 to 10 mg/mL in and while higher IC and MIC values against and -hemolytic were found. From scanning electron microscopy, the extract of the young fruit of promoted morphological changes in the bacterial cells by disrupting the bacterial cell walls, inducing leakage of the cellular content, and generating the abnormal accumulation of cells. The mechanism of action of the extract for this antibacterial effect may be the disruption of the cell membrane and abnormal cell aggregations. Regression analysis of the results suggests the correlation between total phenolic and total flavonoid contents and antioxidant and antibacterial effects. Baicalin was found to have a high correlation with an inhibitory effect against -hemolytic while three unidentified peaks, which could be flavones, showed high correlations with an inhibitory effect against , , and .
从泰国的廊开省和北大年省收集的种子、幼果和花朵的提取物在体外显示出抗氧化和抗菌活性，可对抗包括、、、-溶血和的临床分离的人畜共患病细菌。从种子提取物的制备过程中获得了橙色晶体和黄色沉淀物。来自廊开省种子的橙红色晶体表现出强烈的体外 2,2-二苯基-1-苦基肼（DPPH）清除作用（EC 值= 25.99 ± 3.30 μg/mL）和对和-溶血的抗菌作用，而来自同一来源的黄色沉淀物仅表现出抗氧化作用。分光光度法和 HPLC 技术对 样品中植物化学物质的定量分析表明，它们含有不同量的总酚、总黄酮和三种主要的黄酮类化合物；黄芩苷、黄芩素和白杨素含量。含有低含量类黄酮的幼果提取物仍然对测试细菌具有抗菌作用，其 IC 值低于 1 mg/mL，对 和 的 MIC 值在 4 至 10 mg/mL 之间，而对 和-溶血的 IC 和 MIC 值更高。扫描电子显微镜显示，幼果提取物通过破坏细胞壁、诱导细胞内容物泄漏以及产生细胞异常积聚来促进细菌细胞的形态变化。这种提取物的抗菌作用机制可能是破坏细胞膜和异常细胞聚集。结果的回归分析表明总酚和总黄酮含量与抗氧化和抗菌作用之间存在相关性。黄芩苷与抑制 -溶血作用高度相关，而三个未知峰（可能是类黄酮）与抑制 、 、 和 作用高度相关。
