Laboratory of Air Pollution and Global Climate Change, Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India.
Environ Sci Pollut Res Int. 2021 Sep;28(33):45434-45449. doi: 10.1007/s11356-021-13963-x. Epub 2021 Apr 17.
The UV-B-induced signals play a crucial role in improving the analeptic values of medicinally important plants. Eclipta alba L. (Hassak), commonly known as False Daisy, holds supreme stature with its pharmaceutical association in treating various ailments, particularly in Ayurvedic medicine. The present study aimed to evaluate the response of E. alba plants exposed to ambient (AT) and two different supplemental UV-B doses (eUV-B, ambient ±7.2 kJ m day), i.e., intermittent (IT) and continuous (CT) UV-B treatment for 130 and 240 h respectively. Antioxidative activities and medicinally important compounds (wedelolactone) were measured in different plants' parts at three growth stages. Under both the eUV-B treatments, the photosynthetic pigments were adversely affected (along with reductions in protein content) with a concomitant increase in secondary metabolites. Substantial variations in enzymatic antioxidants and non-enzymatic compounds showed the adaptive resilience strategies of plants against eUV-B. The wedelolactone content increased in leaves but compromised in stem and roots under IT. The results concluded that IT UV-B exposure led to the improvement of plant growth and the yield of wedelolactone compared to CT, suggesting its ameliorative role in improving the test plant's medicinal value.
UV-B 诱导信号在提高药用植物的苏醒值方面起着至关重要的作用。Eclipta alba L.（Hassak），俗称False Daisy，因其在治疗各种疾病方面的药用价值而具有至高无上的地位，特别是在阿育吠陀医学中。本研究旨在评估暴露于环境（AT）和两种不同补充 UV-B 剂量（eUV-B，环境 ±7.2 kJ m day）下的 E. alba 植物的反应，即间歇性（IT）和连续（CT）UV-B 处理分别为 130 和 240 h。在三个生长阶段测量了不同植物部分的抗氧化活性和药用重要化合物（wedelolactone）。在两种 eUV-B 处理下，光合色素都受到了不利影响（同时蛋白质含量降低），同时次生代谢物增加。酶抗氧化剂和非酶化合物的大量变化显示了植物对 eUV-B 的适应弹性策略。wedelolactone 的含量在叶片中增加，但在 IT 下在茎和根中减少。结果表明，与 CT 相比，IT UV-B 暴露可提高植物生长和 wedelolactone 的产量，表明其在提高试验植物药用价值方面具有改善作用。
