Botany and Microbiology Department, Faculty of Science, Helwan University, Cairo, Egypt.
Biology Department, College of Sciences, Taif University, Taif, Saudi Arabia.
Int J Phytoremediation. 2021;23(6):641-651. doi: 10.1080/15226514.2020.1847035. Epub 2020 Nov 24.
In the present study, we assessed seasonal variation in the accumulation potential of wild mint () to heavy metals as well as the chemical composition and antioxidant activity of the essential oil of mint in polluted and unpolluted watercourses. The results indicated that the wild mint showed seasonal fluctuations in accumulation potential for heavy metals proved by bioaccumulation factor (BF) and translocation factor (TF). The all measured heavy metals, except Pb were retained in the underground parts. Summer plants accumulated the highest concentrations of Al, Cd, Cr and Fe in their root, while the lowest concentration of Ni in their shoot. The bioaccumulation factor for Cd, Cu, Mn, Ni, Zn and Co was greater than one, while the translocation factor of the investigated metals (except Pb) did not exceed one, indicating the potential of wild mint for phytostabilization of these metals in contaminated wetlands. The yield and composition of mint essential oil (MEO) were affected by harvesting season and heavy metals pollution. GC/MS showed that isomenthone, cis-piperitenone oxide, menthone and pulegone, were the main oil constituents. Mint essential oil show promising antioxidant activity by 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay under pollution stress. The maximum reducing power of MEO were obtained during autumn and summer seasons (polluted canals).In conclusion, summer is the ideal season for harvesting wild mint plants for the maximum plant biomass, oil yield, high radical scavenging activity of MEO and to monitor pollution in contaminated wetlands.
在本研究中，我们评估了野生薄荷（）对重金属的积累潜力的季节性变化，以及受污染和未受污染水道中薄荷精油的化学成分和抗氧化活性。结果表明，野生薄荷对重金属的积累潜力表现出季节性波动，这可以通过生物积累因子（BF）和迁移因子（TF）来证明。除 Pb 外，所有测量的重金属均保留在地下部分。夏季植物在根部积累了最高浓度的 Al、Cd、Cr 和 Fe，而在地上部分积累了最低浓度的 Ni。Cd、Cu、Mn、Ni、Zn 和 Co 的生物积累因子大于 1，而研究金属的迁移因子（除 Pb 外）不超过 1，表明野生薄荷具有稳定受污染湿地中这些金属的潜力。薄荷精油（MEO）的产量和组成受到收获季节和重金属污染的影响。GC/MS 表明，异薄荷酮、顺式-胡椒烯氧化物、薄荷酮和胡薄荷酮是主要的油成分。在污染胁迫下，薄荷精油通过 2,2'-二苯基-1-苦基肼（DPPH）自由基清除试验显示出有希望的抗氧化活性。在秋季和夏季（受污染的运河），MEO 的最大还原力最高。总之，夏季是收获野生薄荷植物的理想季节，可以获得最大的植物生物量、油产量、MEO 的高自由基清除活性，并监测受污染湿地的污染。
