Xu Wenliang, Shi Danxia, Chen Kuanmin, Popovich David G
School of Food and Advanced Technology, Massey University, Palmerston North, New Zealand.
School of Science, Engineering & Technology, RMIT Vietnam, Ho Chi Minh, Vietnam.
Phytochem Anal. 2025 Apr;36(3):529-536. doi: 10.1002/pca.3448. Epub 2024 Sep 5.
A rapid procedure was developed for the targeted isolation and assessment of antibacterial compounds from plant-based materials. The effectiveness of this method was demonstrated using Feijoa sellowiana fruit peels.
The objectives of this study are as follows: develop an efficient procedure utilizing direct thin-layer chromatography (TLC)-bioautography to facilitate the targeting, identification, and purification of antibacterial compounds from plant extracts and delineate a method based on TLC-bioautography to determine the minimum effective dose (MED), alongside a colorimetric broth microdilution aided by high-performance liquid chromatography (HPLC) for evaluating the isolated active compounds.
Active compounds were targeted using TLC-bioautography against Staphylococcus aureus, and the identification was achieved through liquid chromatography-mass spectrometry (LC-MS) combined with Compound Discoverer. Purification was carried out using a customized separation method. The structure was confirmed using nuclear magnetic resonance (NMR) spectroscopy. The MED, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) were determined by two enhanced antibacterial assays.
The main antibacterial compound identified was flavone. A TLC-bioautography-based antibacterial assay and a colorimetric broth microdilution assisted by HPLC were described as the enhanced antibacterial assay protocols. The MED, MIC, and MBC of flavone against S. aureus were found to be 4.2-5.2 μg/cm, 225-275 μg/mL, and 550-650 μg/mL, respectively. Similarly, the MED, MIC, and MBC against Escherichia coli were determined to be 5.2-6.1 μg/cm, 325-375 μg/mL, and 375-425 μg/mL, respectively.
This study proposed an enhanced bioassay-guided separation technique for the isolation of antibacterial compounds from plants, along with two improved methods for assessing the antibacterial efficacy of insoluble or colored compounds.
开发了一种从植物材料中靶向分离和评估抗菌化合物的快速程序。使用费约果果皮证明了该方法的有效性。
本研究的目的如下：开发一种利用直接薄层色谱（TLC）-生物自显影的高效程序，以促进从植物提取物中靶向、鉴定和纯化抗菌化合物，并描述一种基于TLC-生物自显影的方法来确定最小有效剂量（MED），同时结合高效液相色谱（HPLC）辅助的比色肉汤微量稀释法来评估分离出的活性化合物。
使用针对金黄色葡萄球菌的TLC-生物自显影靶向活性化合物，并通过液相色谱-质谱联用（LC-MS）结合化合物发现软件进行鉴定。采用定制的分离方法进行纯化。使用核磁共振（NMR）光谱确认结构。通过两种增强的抗菌试验确定MED、最低抑菌浓度（MIC）和最低杀菌浓度（MBC）。
鉴定出的主要抗菌化合物为黄酮类。基于TLC-生物自显影的抗菌试验和HPLC辅助的比色肉汤微量稀释法被描述为增强的抗菌试验方案。黄酮对金黄色葡萄球菌的MED、MIC和MBC分别为4.2-5.2μg/cm、225-275μg/mL和550-650μg/mL。同样，对大肠杆菌的MED、MIC和MBC分别确定为5.2-6.1μg/cm、325-375μg/mL和375-425μg/mL。
本研究提出了一种增强的生物测定指导的分离技术，用于从植物中分离抗菌化合物，以及两种改进的方法来评估不溶性或有色化合物的抗菌效果。
