Department of Biology, University of Aveiro, Aveiro, Portugal.
Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal.
J Hazard Mater. 2020 Apr 15;388:121783. doi: 10.1016/j.jhazmat.2019.121783. Epub 2019 Nov 28.
Volatile organic compounds (VOCs) are produced by plants, fungi, bacteria and animals. These compounds are metabolites originated mainly in catabolic reactions and can be involved in biological processes. In this study, the airborne effects of five monoterpenes (α-pinene, limonene, eucalyptol, linalool, and menthol) on the growth and oxidative status of the rhizobial strain Rhizobium leguminosarum E20-8 were studied, testing the hypothesis that these VOCs could influence Rhizobium growth and tolerance to cadmium. The tested monoterpenes were reported to have diverse effects, such as antibacterial activity (linalool, limonene, α-pinene, eucalyptol), modulation of antioxidant response or antioxidant properties (α-pinene and menthol). Our results showed that non-stressed cells of Rhizobium E20-8 have different responses (growth, cell damage and biochemistry) to monoterpenes, with α-pinene and eucalyptol increasing colonies growth. In stressed cells the majority of monoterpenes failed to minimize the detrimental effects of Cd and increased damage, decreased growth and altered cell biochemistry were observed. However, limonene (1 and 100 mM) and eucalyptol (100 nM) were able to increase the growth of Cd-stressed cells. Our study evidences the influence at-a-distance that organisms able to produce monoterpenes may have on the growth and tolerance of bacterial cells challenged by different environmental conditions.
挥发性有机化合物（VOCs）由植物、真菌、细菌和动物产生。这些化合物是主要来源于分解代谢反应的代谢物，可以参与生物过程。在这项研究中，研究了五种单萜（α-蒎烯、柠檬烯、桉叶油醇、芳樟醇和薄荷醇）对根瘤菌菌株根瘤菌 E20-8 生长和氧化状态的空气传播影响，检验了这些 VOCs 可能影响根瘤菌生长和耐受镉的假设。据报道，测试的单萜具有多种作用，如抗菌活性（芳樟醇、柠檬烯、α-蒎烯、桉叶油醇）、调节抗氧化反应或抗氧化特性（α-蒎烯和薄荷醇）。我们的结果表明，非应激状态下的根瘤菌 E20-8 细胞对单萜有不同的反应（生长、细胞损伤和生物化学），α-蒎烯和桉叶油醇增加菌落生长。在应激细胞中，大多数单萜未能减轻 Cd 的有害影响，反而观察到损伤增加、生长减少和细胞生物化学改变。然而，柠檬烯（1 和 100mM）和桉叶油醇（100nM）能够增加 Cd 应激细胞的生长。我们的研究证明了能够产生单萜的生物体可能对受到不同环境条件挑战的细菌细胞的生长和耐受具有远距离影响。
