Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Polo Annunziata, 98168, Messina, Italy.
Department of Public Health and Pediatrics, Microbiology Division, University of Turin, Via Santena 9, 10126, Turin, Italy.
BMC Complement Med Ther. 2020 Mar 17;20(1):89. doi: 10.1186/s12906-020-2877-x.
Hydrolates, complex mixtures containing traces of essential oils (EOs), are inexpensive, easy to make and less toxic than their corresponding EOs. The antibacterial and antifungal activity of the hydrolate of Coridothymus capitatus (L.) Reichenb. fil. (Lamiaceae) alone and in combination with antimicrobial drugs, such as tetracycline and itraconazole, were evaluated.
The chemical composition was analysed by gas-chromatography-mass spectrometry (GC-MS). Standard methods were performed to evaluate the susceptibility of some Gram-positive and Gram-negative bacteria, and Candida spp. to the hydrolate, in comparison with its EO. The hydrolate mechanism of action was assayed by propidium iodide and MitoTracker staining. Checkerboard tests were carried out for combinations studies.
GC-MS identified 0.14% (v/v) of total EO content into hydrolate and carvacrol as a dominant component. The hydrolate showed a good antimicrobial activity against bacteria and yeasts. It exhibited a synergistic effect with itraconazole against Candida krusei, and an additive effect with tetracycline against methicillin-resistant Staphylococcus aureus strains. Hydrolate changed the membranes permeability of bacteria and yeasts and altered mitochondrial function of yeasts.
Our study extends the knowledge by exploiting non-conventional antimicrobial agents to fight the emergence of antibiotic resistance.
水醇提物是一种含有痕量精油（EO）的复杂混合物，它价格低廉、易于制备且毒性低于相应的 EO。本文单独评估了香桃木（唇形科）水醇提物及其与抗菌药物（如四环素和伊曲康唑）联合的抗菌和抗真菌活性，并对其化学成分进行了分析。
采用气相色谱-质谱联用（GC-MS）对化学成分进行分析。采用标准方法评估水醇提物及其 EO 对某些革兰氏阳性菌和革兰氏阴性菌以及念珠菌属的敏感性。通过碘化丙啶和 MitoTracker 染色测定水醇提物的作用机制。采用棋盘试验进行联合研究。
GC-MS 鉴定出水醇提物中含有 0.14%（v/v）的总 EO 含量，其中香芹酚为主要成分。水醇提物对细菌和酵母具有良好的抗菌活性。它对克柔念珠菌与伊曲康唑表现出协同作用，对耐甲氧西林金黄色葡萄球菌与四环素表现出相加作用。水醇提物改变了细菌和酵母的膜通透性，并改变了酵母的线粒体功能。
本研究通过利用非传统的抗菌剂来对抗抗生素耐药性的出现，扩展了相关知识。
