Al-Nimer Marwan S M, Wahbee Zainab
Department of Pharmacology, College of Medicine, Al-Mustansiriya University, Baghdad, Iraq.
Senior Lecturer in Medical Physics, Department of Physiology, College of Medicine, Al-Mustansiriya University.
J Intercult Ethnopharmacol. 2017 Jul 12;6(3):280-283. doi: 10.5455/jice.20170630092831. eCollection 2017 Jul-Sep.
(comfrey) is a medicinal plant commonly used in decoction and to treat ailments. It protects the skin against ultraviolet (UV)-irradiation. UV irradiation may induce variable effects on the constituents of herbal extracts and thereby may limit or improve the advantages of using these extracts as medicinal supplements. This study aimed to assess the effect of UV radiations including UV-A, UV-B, and UV-C on the constituents of aqueous and alcoholic extracts.
Comfrey extracts (1% w/v) were prepared using distilled water, ethanol, and methanol. They were exposed to wavelengths of UV-A, UV-B, and UV-C for 10 min. The principal peak on the UV-spectroscopy scanning, the flavonoids, reducing power, and the allantoin levels were determined before and after irradiation.
UV irradiation reduces the magnitude of the principle peak at 355 nm wavelength of the aqueous infusion and methanol extracts. It improves the levels of flavonoids and reducing power of the aqueous extracts and increases the levels of allanotoin in aqueous and methanol extracts.
UV-radiation enhances the yields of active ingredient of comfrey extracted with methanol, whereas improves the flavonoids, reducing power, and allantoin levels of comfrey extracted by the aqueous infusion method. UV-radiation reduces the levels of flavonoids, reducing power and allantoin when the comfrey extracted by alcohols.
紫草是一种常用于煎剂并治疗疾病的药用植物。它能保护皮肤免受紫外线（UV）照射。紫外线照射可能会对草药提取物的成分产生不同影响，从而可能限制或提高使用这些提取物作为药用补充剂的优势。本研究旨在评估紫外线A、紫外线B和紫外线C对水提取物和醇提取物成分的影响。
用蒸馏水、乙醇和甲醇制备紫草提取物（1%w/v）。将它们暴露于紫外线A、紫外线B和紫外线C波长下10分钟。在照射前后测定紫外光谱扫描的主峰、黄酮类化合物、还原能力和尿囊素水平。
紫外线照射降低了水浸液和甲醇提取物在355nm波长处主峰的幅度。它提高了水提取物中黄酮类化合物的水平和还原能力，并增加了水提取物和甲醇提取物中尿囊素的水平。
紫外线辐射提高了用甲醇提取的紫草活性成分的产量，而提高了用水浸法提取的紫草中黄酮类化合物、还原能力和尿囊素的水平。当用醇提取紫草时，紫外线辐射会降低黄酮类化合物、还原能力和尿囊素的水平。
