Extraction And Analysis On Essential Oil And Shikimic Acid Of Illicium Verum Hook.f.

Traditional Chinses Medicine (TCM) has become the popular apot since toxicity and limitation of synthetical drug is reciognized gradually. Illicium verum Hook. f. has been widely applied on Chinese herbal medicine. There are large areas of Illicium verum Hook. f. plantation growing in Guangxi, China. In China, people often use it to cure neurasthenic, dyspepsia, acariasis, etc. Therefore, it has wide market prospect.This paper has made the best of calculational superiority of our laboratory, so experimentation and academic calculation have been combined organically in the study. Extraction and purification of TCM was studied in this paper with Illicium verum Hook. f. as its object. The main contents are as follows:①For the extraction of essential oil, the extraction process was optimized by orthogonal design. Using the ratio of essential oil yield as indicator and the screen mesh of medicinal materials, quantity of water, soaking time and extracting time as affecting factors, the L16(45) orthogonal array design was conducted. A regression model of standard multinomial was constructed to predict the ratio of essential oil yield with satisfactory results. The optimized extraction process was as follows: screen mesh was 80 screen meshes, being soaked in 12 times water for 15 hours and distilled for 3 hours with vapor. Under condition, the results of the model prediction was 11.967%. In order to validate the reliability of the experiment, three paralle experiments of that condition were carried with the average ratio of essential oil yield was high to 11.895%, and reproducibility of the experiments was very good. The result of experiment was so adjacent to that of the model prediction, which can confirm the model with strong reliability. Crude extraction emphasized on microwave-assisted extraction and ultrasound-assisted extraction to reduce extraction time and energy consumption. The saved extraction time was more than one hour.②The essential oil was analyzed using GC/MS, 50 compositions had been separated and 48 compounds had been identified. And the main compound (66.947%) was trans- anethole, the others was less. Through reduction of the molecular electronegativity-distance vector, a new molecular structural characterization (MSC) method called reduced vector of molecular electronegativity-distance (VMEDR) could be obtained. Quantitative structure—retention relationship (QSRR) studies of the retention times of 48 components from essential oil of Illicium verum Hook. f. were performed by the VMEDR. Through multiple linear regression (MLR), a model (M1) with the correlation coefficient (R2) of 0.943 and the standard deviation (SD) of 3.136 could be achieved. Then the model was evaluated by performing the cross validation with the leave- one - out (LOO) procedure and the results with correlation coefficient(R2CV1) of 0.737 and standard deviation (SDCV) of 4.823 could be obtained. Through the same method another model of VMED with results of R2=0.942, SD=3.149, R2CV=0.722 and SDCV=4.962 could be obtained. We could get the conclusion that the stability and predictability of the model of VMEDR were better than that of the model of VMED. It showed that the reduction of molecular electronegativity-distance was successful. But the results of VMEDR were still not satisfactory. So a method, which based on three non-bonded (electrostatic, van der waals and hydrophobic) factors, directly related to bio-activities, called three dimensional holographic vector of atomic interaction field (3D-HoVAIF) was proposed to study the QSRR model of 48 compounds in the essential oil too. The descriptors were selected by stepwise multiple regression (SMR). The established model by partial least square regression (PLS) was proved to be of stability and predictability since its correlation coefficients of fitting (R2cum=0.930) and cross validation (Q2cum=0.892) respectively. The model of multiple linear regression (MLR) was built up strictly with its correlation coefficients (R2=0. 0.9374), leave-one-out cross-validation (Q2cum=0.9125) respectively. Obviously, the statistical results indicated that 3D-HoVAIF descriptors were proved to be potent in characterizing chromatogiaphic retention behaviour of volatile components of Illicium verum Hook. f. and the models were proved to be of stability and predictability.③For the extraction of shikinmic acid, we used microwave-assisted extraction and ultrasound-assisted extraction. When ultrasonic extraction was investigated, 4 main factors of concentration of ethanol, extraction time, ratio of liquid to solid (L/S) and granularity was chosen for a group of 17 levels uniform experiments, the results of which was managed with SPSS and applied software to build a model. From the model we could find that with 45% ethanol, 40-60 meshes, 30 minutes extraction time and the ratio of liquid to solid being 30, maximum extraction yield of 9.15% was obtained. When the method of microwave extraction was discussed, a group of L16 (45) orthogonal experiments were performed to study 4 factorss of concentration of ethanol, extraction time, ratio of liquid (L/S) and temperature (microwave firepower). The results indicated best efficiency of 9.21 was obtained under the condition of ethanol concentration 50%, extraction time 10min, ratio of liquid (L/S) 30 and firepower 352W. Then, in the best conditions, we picked up 10 grams of powder to repeat amplification experiment. After ethanol was steamed out, we used chloroform and butanol extraction more than once. The part of butanol phase undergoed silica gel adsorption. The portions eluted by mixture (chloroform / methanol =10: 1) were isolated ande purify with silica gel column chromatography repeatedly. Evaporate the eluate and get solid weights 0.331 grams with the purity of 91.2%.④Atomic electronegativity interaction vector (VAEI) and atomic hybridation state index (AHSI) were employed for quantitative structure spectroscopy relationship modeling of 13C NMR chemical shifs of 60 carbon atoms in five molecules of shikinmic acid and its analogs. Through multiple linear regression (MLR), a model with the correlation coefficient (RMM1) of 0.963 and the standard deviation (SDMM1) of 13.924 could be achieved. Leave-one-out (LOO) method and cross-validation (CV) were combined to test the prediction ability of the model and the satisfied results with correlation coefficient (RCV1) of 0.936 and standard deviations (SDCV1) of 15.062 could be obtained, respectively. Then, the VAEI was improved by some change. Through multiple linear regression (MLR), a better model with the correlation coefficient (RMM2) of 0.965 and the standard deviation (SDMM2) of 13.595 could be achieved. The model also was tested by Leave-one-out (LOO) method and the more satisfied results with correlation coefficient (RCV2) of 0.959 and standard deviations (SDCV2) of 14.625 could be obtained, respectively. The results show that the change of VAEI is successful. But, it remains to be a two-dimensional descriptor of analysis situs, cannot differentiate the structure of cis-trans isomerism and the optical isomerism. It remains to be improved further. The results suggest that the model based on VAEI and AHSI can be used to predict 13C NMR chemical shifts of shikinmic acid and its analogs with satisfactory stability and predictability. It may provide beneficial reference for QSSR study of shikinmic acid and its analogs.