Optimized Extraction, Quantitative Evaluation And Antioxidation In Vitro Of Curcumins From Herbal Curcuma Species

Rheumatoid arthritis, heart disease, cerebrovascular disease, malignant tumor etc are related to the oxidative damages which caused by free radical. Free radical is active and variety, can damage a variety of biological macromolecules in cells. Some medical research had show that curcumin has the function of regulating immune, restraing central nervous, improving blood flow, free-radical damage, protecting liver, analgesia, reducing blood lipid, resisting radiation, and so on. Curcumin has been widely used in food, pharmaceutical industries etc. The research of antioxidant activity in Curcuma has become hot at home and abroad. In this study, Taking domestic commonly used curcuma from China as materials, by establishing the method to measure the contents of curcuminoids in diffirent Curcuma, optimizating the extraction method under ultrasonic assisted and comparing the antioxidant of ethanol extraction among these materials in vitro, to select high quality germplasm resources, to inspect the genetic diversity and to investigate the interspecific relationship in Curcuma, The main results were as follows:1. Optimization of the ultrasonic assisted extraction conditions for CurcumaTo evaluate the effectiveness of ultrasonic assisted extraction and establish the optimized extraction by the central principles(CCD), the response surface method(RSM) with3factors and3levels. The optimal results are obtained as follows:ultrasonic extraction time was15min, ethanol concentration was85.0%, and the ratio of solvent volume to Curcuma breviscapus mass of13mL/g, extracted3times. The equation correlation coefficient r is0.9227. The observed and predicted values are close to each other, which proved that the optimization of supersonic extraction process Star design experiment fitting for the breviscapine from Erigeron breviscapus by CCD-RSM is reasonable and successful.2. The method that established to determine the curcuminoids of Curcuma:HPLC and uv-visible spectrophotometer methodThe results of UV and HPLC prove each other on six herbal Curcuma species. According to the UV data, the contents of curcuminoids of Curcuma were diffirent, The contents of the three principle curcumminoids by HPLC also varied remarkably, Although the same species from same regions, the contents of curcuminoids were significantly different. Therefore, C. longa could be considered as the desirable botanical source of curcuminoids. It was noteworthy that the highest amounts of curcuminoids samples (both cultured and uncultured) are in Sichuan Province. This result was in accordance with the traditional Chinese medicine (TCM) theory that Sichuan is the authentic cultivation region for C. longa. Furthermore, the data showed that cucumin was the main contents in curcuminoids derived from the six species, and the higher contents of cucurmin following the higher contents of BDMC and DMC, and the ratio of BDMC and DMC in the total curcuminnoids was similar in the samples which the curcuminoids contents>20mg/g by UV-visible spectroscopy that their cucurmin contents meet the Chinese Pharmacopoeia’s rule. So the UV method can be used for standardization of curcuminoids extracts from Curcuma.3. The vitro antioxidant effects of different plants’ethanol extraction.By comparing the vitro antioxidant ability among the ethanol extraction of diffirent Curcuma, curcumin, DMC and BDMC, we obtained the result:curcumin, DMC and BDMC had stronger ability in scavenging free radicals than direct ethanol extractions from curcuma plants. As the ethanol extraction, the high content of total curcuminoids means that they have stonger ability to eliminate DPPH free radical and reducing power, but to hydroxyl radicals, superoxide anion free radicals and ABTS radical, the higher total curcuminoids didn’t has advantages.On the six herbal Curcuma species, C. longa and C. chuanhuangjiang had the most big ability in scavenging DPPH free radicals and FRAP. C. longa and C. sichuanensis had the biggest ability in scavenging ABTS free radicals.When scavenging O2-·, C. sichuanensis had the biggest ability. But to·OH, scavenging ability didn’t make some diffirence among the six species.