艾蒿中黄酮的提取纯化及抑菌实验

黄酮类物质具有抗菌、抗炎、抗肿瘤等多种功效.艾蒿中含有丰富的黄酮物质.采用超声波辅助回流提取艾蒿中的黄酮,用分光光度法在510nm处测量吸光度.通过响应面分析,得到最佳工艺参数为温度74℃,超声波功率200W,提取时间92min,乙醇浓度60%,料液比1:35.在该条件下提取两次,测得提取率为91.5%.用AB-8大孔树脂将其纯化.将纯化后的黄酮进行抑菌试验.采用二倍稀释法,用滤纸片法测量艾蒿中黄酮对大肠杆菌、金黄色葡萄球菌、黑曲霉菌、白曲霉菌的最低抑菌浓度.黄酮对大肠杆菌和金黄色葡萄球菌的最低抑菌浓度为0.25mg/mL,对黑曲霉菌和白曲霉菌的最低抑菌浓度为1mg/mL,从而确定大肠杆菌和金黄色葡萄球菌对黄酮较敏感.     

大孔树脂分离纯化艾蒿黄酮的研究

以总黄酮含量和总黄酮回收率为考察指标,研究大孔树脂分离纯化艾蒿黄酮的工艺.结果表明AB-8型树脂的纯化效果最好.通过对纯化影响因素的研究,确定了AB-8型大孔树脂纯化艾蒿黄酮的最佳工艺条件为:艾蒿提取物黄酮浓度为37.56 mg/mL时,艾蒿提取物上样量为4 mL,先用pH5的水淋洗,再用pH4的50%的乙醇洗脱,洗脱剂用量为5倍湿树脂体积.AB-8大孔树脂按上述确定的吸附洗脱条件可重复使用3次.艾蒿黄酮经上述工艺纯化后总黄酮含量达到69.37%,总黄酮回收率为64.98%.     

Antioxidant action of ganghwayakssuk (Artemisia princeps Pamp.) in combination with ascorbic acid to increase the shelf life in raw and deep fried chicken nuggets

Raw and deep fried chicken nuggets containing various levels of ganghwayakssuk ethanolic extract (GE) in combination with ascorbic acid (Aa) were evaluated for shelf-life during refrigerated storage (4 °C). The pH and color (lightness, redness, and yellowness) values of raw and deep fried samples were significantly affected by the addition of GE (P < 0.05). All antioxidant combinations except for Aa + GE 0.01 were effective at delaying lipid oxidation (CD, POV, and TBARS) when compared to the control or Aa. Raw samples with GE 0.2 and Aa + GE 0.1 exhibited lower bacterial populations during storage. The sensory characteristics (color, juiciness, flavor, tenderness, and overall acceptability) did not differ significantly in all deep fried chicken nugget samples, except color, whereas storage time had a significant effect (P < 0.05). The results suggest the possibility of utilizing raw and deep fried chicken nuggets with a mixture of ganghwayakssuk and ascorbic acid for the increase of shelf-life and quality.     

Optimized Conditions for the Extraction of Eupatilin in Artemisia asiatica by Pressurized Liquid Extraction

Abstract

The effect of temperature and solvent on the extraction of Artemisia asiatica using pressurized liquid extraction was examined. These two parameters were operated according to central composite design followed by response surface analysis to obtain the highest extraction efficiency. Determination of eupatilin was carried out by high performance liquid chromatography coupled with a diode array detector. While the rise in temperature could increase the yield of the total extract, the content of eupatilin was decreased in high temperature. In addition, high ethanol proportion maximized the contents of eupatilin in the total extract.     

黄花蒿(Artemisia annua L.)提取物对两种病原真菌的生物活性

以石油醚Ⅰ(30℃～60℃)、石油醚Ⅱ(60℃～90℃)、乙醇和丙酮等4种溶剂对黄花蒿的根、茎、叶进行初步提取,采用生长速率法测定不同提取物对玉米小斑病菌、棉花枯萎病菌的抑菌活性。结果表明,黄花蒿提取物对玉米小斑病菌的生物活性好于棉花枯萎病菌;黄花蒿叶的提取物抑菌效果最好,根的抑菌效果最差;叶的石油醚(60℃～90℃)提取物对玉米小斑病菌EC50为156.32mg/L;而叶的丙酮提取物对玉米小斑病菌的EC50为82.37mg/L。     

超声强化溴化1-乙基-3-甲基咪唑从黄花蒿中提取青蒿素

利用超声强化[emim]Br(溴化1-乙基-3-甲基咪唑)-水体系从黄花蒿粉末中提取青蒿素. 正交实验和单因素实验结果表明,影响黄花蒿中青蒿素提取因素的显著性次序为液固比>提取时间>提取温度>超声波功率>占空比. 综合考虑单因素实验结果及成本,得出优化工艺条件为黄花蒿原料粒度0.38 mm,液固比50 mL/g,提取时间30 min,提取温度20℃,超声波功率600 W,占空比1.6 s/0.4 s. 在上述条件下青蒿素提取量为4.37 mg/g,提取率为97%.     

酶法提取茵陈总黄酮的工艺研究

以酶法提取茵陈中黄酮类化合物,用紫外-可见比色法和芦丁为标准品测定茵陈总黄酮的得率,研究酶用量、pH值、温度、乙醇浓度、提取时间对黄酮得率的影响。最佳工艺条件为纤维素酶的浓度0.10 mg/mL,pH=4.2,温度50℃,乙醇浓度为60%,恒温振荡1.5 h,此条件下黄酮的得率为3.513%。     

Optimization of Ultrasound-Assisted Extraction of Artemisinin from Artemisia annua L. by Response Surface Methodology

Artemisinin is a compound extracted from Artemisia annua L. with a remarkable curative effect against malaria. It can be extracted using ultrasound-assisted extraction (UAE) and then detected via HPLC. In this study, response surface methodology (RSM) was used to optimize UAE conditions for obtaining the maximum yield of artemisinin. Three independent variables (ratio of solvent to material, extraction temperature, and ultrasonic power) were evaluated using the Box-Behnken experimental design, with the yield of artemisinin as a response variable. Experimental data were highly fitted to a mathematical-regression model using multiple linear regression (MLR). Based on response surface plots, the three independent variables exhibited interactive effects on the yield of artemisinin. The optimal extraction conditions were as follows: 42.71 mL/g ratio of solvent to material, 41.86°C extraction temperature and 120 W ultrasonic power. The predicted yield of artemisinin by model was 0.7848%, whereas the actual yield in the extracts was 0.7826% ± 0.0790% in adjusted optimal conditions, with a relative error of 0.28%. The results undoubtedly demonstrated that RSM could be used to explore the optimum conditions of artemisinin extraction.     

藜蒿黄酮超临界CO2(SFE-CO2)萃取条件的研究

采用超临界CO2萃取藜蒿中黄酮类物质。考虑萃取温度，压力，夹带剂用量等因素在不同水平下对藜蒿黄酮提取率的影响，并对结果进行方差分析和显著性检验。实验表明：以1.5ml/g无水乙醇为夹带剂在35℃，30MPa条件下萃取为最佳条件。