National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, Cluj-Napoca 400293, Romania.
National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, Cluj-Napoca 400293, Romania.
Sci Total Environ. 2016 Nov 1;569-570:489-495. doi: 10.1016/j.scitotenv.2016.06.147. Epub 2016 Jun 27.
Exposure to sustained low intensity microwaves can constitute a stress for the plants, but its effects on plant secondary chemistry are poorly known. We studied the influence of GSM and WLAN-frequency microwaves on emissions of volatile organic compounds and content of essential oil in the aromatic plant Ocimum basilicum L. hypothesizing that microwave exposure leads to enhanced emissions of stress volatiles and overall greater investment in secondary compounds. Compared to the control plants, microwave irradiation led to decreased emissions of β-pinene, α-phellandrene, bornyl acetate, β-myrcene, α-caryophyllene and benzaldehyde, but increased emissions of eucalyptol, estragole, caryophyllene oxide, and α-bergamotene. The highest increase in emission, 21 times greater compared to control, was observed for caryophyllene oxide. The irradiation resulted in increases in the essential oil content, except for the content of phytol which decreased by 41% in the case of GSM-frequency, and 82% in the case of WLAN-frequency microwave irradiation. The strongest increase in response to WLAN irradiation, >17 times greater, was observed for hexadecane and octane contents. Comparisons of volatile compositions by multivariate analyses demonstrated a clear separation of different irradiance treatments, and according to the changes in the volatile emissions, the WLAN-frequency irradiation represented a more severe stress than the GSM-frequency irradiation. Overall, these results demonstrating important modifications in the emission rates, essential oil content and composition indicate that microwave irradiation influences the quality of herbage of this economically important spice plant.
持续低强度微波辐射会对植物造成压力，但人们对其对植物次生化学物质的影响知之甚少。我们研究了 GSM 和 WLAN 频率微波对芳香植物罗勒（Ocimum basilicum L.）挥发物排放和精油含量的影响，假设微波辐射会导致应激挥发物的排放增加，以及次生化合物的整体投资增加。与对照植物相比，微波辐射导致 β-蒎烯、α-水芹烯、乙酸龙脑酯、β-月桂烯、α-石竹烯和苯甲醛的排放减少，但桉树脑、茴香脑、石竹烯氧化物和α-佛手柑烯的排放增加。与对照相比，氧化石竹烯的排放增加最多，增加了 21 倍。辐射导致精油含量增加，除了 GSM 频率下植醇含量下降 41%，WLAN 频率下下降 82%。WLAN 辐射的响应增加最强，增加了>17 倍，主要是十六烷和辛烷的含量。多元分析比较挥发性成分表明，不同辐照度处理有明显的分离，根据挥发性排放的变化，WLAN 频率辐射比 GSM 频率辐射代表更严重的应激。总的来说，这些表明排放速率、精油含量和组成发生重要变化的结果表明，微波辐射会影响这种具有经济重要性的香料植物草料的质量。
