Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, P. O. Box 3665, Abha, 61421, Saudi Arabia.
Department of Biology, College of Science, King Khalid University, P. O. Box 9004, Abha, 61421, Saudi Arabia.
BMC Complement Med Ther. 2020 Mar 17;20(1):86. doi: 10.1186/s12906-020-2863-3.
Myrtus communis is a typical plant of Mediterranean area. The different parts of this plant such as berries, branches, and leaves have been used worldwide as a traditional/folk medicine for the treatment of various ailments and diseases.
Ethanolic leaf extract of the plant was prepared by Soxhlet extraction method. Zone of inhibition, minimum inhibitory concentration and minimal bactericidal concentration were determined by well diffusion method and microplate alamar blue assay. GC-MS analysis was carried out to identify the compounds present in the extract. Microscopy and ImageJ software were used respectively for morphology and cell-length measurements. GraphPad Prism was used for statistical analysis.
The ethanolic extract showed strong inhibitory effect against Gram-positive and acid-fast bacteria with significant inhibition-zone size (9-25 mm), MIC (4.87-78 μg/ml), as well as MBC (0.3-20 mg/ml). However, no effect was observed on the growth of Gram-negative bacteria. The growth inhibition was found to be associated with the damage of cell wall as the extract-treated cells were sensitive to cell wall-targeting antibiotics and displayed the cell wall damage-depicting morphological defects. GC-MS analysis confirmed the presence of novel compounds in addition to the most representative compounds of the essential oils/extracts of M. communis of other country origins.
These results demonstrate that M. communis leaf extract could be the source of compounds to be used for the treatment of Gram-positive bacterial infections. This is the first report, which provides insights into the mechanism of action of the extract in inhibiting the growth of Gram-positive bacteria.
桃金娘是地中海地区的一种典型植物。这种植物的不同部分，如浆果、树枝和叶子，已被全世界用作传统/民间药物，用于治疗各种疾病和病症。
采用索氏提取法制备植物叶乙醇提取物。采用平板扩散法和微孔板阿尔玛蓝法测定抑菌圈、最小抑菌浓度和最小杀菌浓度。采用 GC-MS 分析鉴定提取物中存在的化合物。显微镜和 ImageJ 软件分别用于形态和细胞长度测量。GraphPad Prism 用于统计分析。
乙醇提取物对革兰氏阳性菌和抗酸性细菌具有强烈的抑制作用，具有显著的抑菌圈大小（9-25 毫米）、MIC（4.87-78 微克/毫升）以及 MBC（0.3-20 毫克/毫升）。然而，对革兰氏阴性菌的生长没有影响。生长抑制与细胞壁损伤有关，因为提取物处理的细胞对细胞壁靶向抗生素敏感，并显示出细胞壁损伤的形态缺陷。GC-MS 分析证实了除了其他国家来源的桃金娘属精油/提取物的代表性化合物之外，还存在新的化合物。
这些结果表明，桃金娘叶提取物可能是用于治疗革兰氏阳性菌感染的化合物的来源。这是第一个提供有关提取物抑制革兰氏阳性菌生长作用机制的报告。
