Elbasan Fevzi, Arikan-Abdulveli Busra, Ozfidan-Konakci Ceyda, Yildiztugay Evren, Tarhan İsmail, Çelik Berfin
Selcuk University, Faculty of Science, Department of Biotechnology, 42250, Konya, Turkey.
Necmettin Erbakan University, Faculty of Science, Department of Molecular Biology and Genetics, 42090, Konya, Turkey.
Chemosphere. 2024 Sep;363:142924. doi: 10.1016/j.chemosphere.2024.142924. Epub 2024 Jul 22.
With the advent of technological advancements post the industrial revolution, thousands of chemicals are introduced into the market annually to enhance different facets of human life. Among these, pharmaceutical and personal care products (PPCPs), including antibiotics and disinfectants, such as benzalkonium chlorides (BACs), are prominent. BACs, often used for surface and hand disinfection in high concentrations or as preservatives in health products such as nasal sprays and eye drops, may present environmental risks if they seep into irrigation water through prolonged exposure or improper application. The primary objective of this study is to elucidate the tolerance mechanisms that may arise in Lemna minor plants, known for their remarkable capability to accumulate substances efficiently, in response to exogenously applied BACs at varying concentrations. The study applied six different concentrations of BACs, ranging from 0.25 to 10 mg L. The experimental period spanned seven days, during which the treatments were conducted in triplicate to ensure reliability and reproducibility of the results. It was observed that low concentrations of BACs (0.25, 0.5 and 1 mg L) did not elicit any statistically significant changes in growth parameters. However, higher concentrations of BACs (2.5, 5, and 10 mg L) resulted in a reduction in RGR by 20%, 28%, and 36%, respectively. Chlorophyll fluorescence declined significantly at BAC doses of 5 and 10 mg L, with F/F ratios decreasing by 9% and 15%, and F/F ratios by 40% and 39%, respectively. Proline content decreased in all treatment groups, with a 46% reduction at 10 mg L BAC. TBARS and HO contents increased proportionally with BAC dosage, showing the highest increases of 30% and 40% at 10 mg L, respectively. The noticeable increase in SOD enzyme activity at BAC concentrations of 0.5, 1, and 2.5 mg L, with increases of 2.7-fold, 2.2-fold, and 1.7-fold respectively, along with minimal accumulation of HO, suggests that L. minor plants have a strong tolerance to BAC. This is supported by the efficient functioning of the CAT and GST enzymes, especially evident at the same concentrations, where increased activities effectively reduce the buildup of HO. In the AsA-GSH cycle, although variations were observed between groups, the contribution of the GR enzyme to the preservation of GSH content by recycling GSSG likely maintained redox homeostasis in the plant, especially at low concentrations of BACs. The study revealed that L. minor effectively accumulates BAC alongside its tolerance mechanisms and high antioxidant activity. These results underscore the potential for environmental cleanup efforts through phytoremediation.
随着工业革命后技术的进步，每年有成千上万种化学物质被引入市场以改善人类生活的不同方面。其中，药品和个人护理产品（PPCPs），包括抗生素和消毒剂，如苯扎氯铵（BACs），尤为突出。BACs常用于高浓度的表面和手部消毒，或作为鼻喷雾剂和眼药水等保健产品中的防腐剂，如果通过长期接触或不当使用渗入灌溉水中，可能会带来环境风险。本研究的主要目的是阐明浮萍这种以高效积累物质能力著称的植物，在应对不同浓度外源施加的BACs时可能产生的耐受机制。该研究应用了六种不同浓度的BACs，范围从0.25至10 mg/L。实验期为七天，在此期间进行了三次重复处理以确保结果的可靠性和可重复性。观察到低浓度的BACs（0.25、0.5和1 mg/L）在生长参数上未引起任何统计学上的显著变化。然而，较高浓度的BACs（2.5、5和10 mg/L）分别导致相对生长率（RGR）降低了20%、28%和36%。在5和10 mg/L的BAC剂量下，叶绿素荧光显著下降，Fv/Fm比率分别下降了9%和15%，F0/Fm比率分别下降了40%和39%。所有处理组的脯氨酸含量均下降，在10 mg/L BAC时下降了46%。丙二醛（TBARS）和过氧化氢（H2O2）含量随BAC剂量成比例增加，在10 mg/L时分别最高增加了30%和40%。在0.5、1和2.5 mg/L的BAC浓度下，超氧化物歧化酶（SOD）活性显著增加，分别增加了2.7倍、2.2倍和1.7倍，同时H2O2积累量最小，这表明浮萍对BAC具有较强的耐受性。过氧化氢酶（CAT）和谷胱甘肽-S-转移酶（GST）的有效功能也支持了这一点，特别是在相同浓度下，活性增加有效地减少了H2O2的积累。在抗坏血酸-谷胱甘肽（AsA-GSH）循环中，尽管各组之间存在差异，但谷胱甘肽还原酶（GR）通过循环氧化型谷胱甘肽（GSSG）来维持谷胱甘肽（GSH）含量，这可能在植物中维持了氧化还原稳态，尤其是在低浓度BACs的情况下。该研究表明，浮萍在其耐受机制和高抗氧化活性的同时有效地积累了BAC。这些结果强调了通过植物修复进行环境清理的潜力。
