【作者】 强磊；

【导师】 康振生；

【作者基本信息】 西北农林科技大学 ， 植物病理， 2013， 硕士

【摘要】 野胡萝卜（Daucus carota Linn）为伞形科胡萝卜属二年生草本植物。又名鹤虱草，山萝卜。野生于田边、路旁、旷野草丛中，分布于全国各地。其籽实提取的精油称为野胡萝卜籽精油，也称鹤虱油，为深红棕色粘稠液体，具有令人愉快的芳香，有甜、辛、辣的气味。野胡萝卜籽精油中富含多种化学成分，具有多种生物活性，但其提取工艺及抑菌活性研究非常有限。优化其萃取工艺，测试其抑菌活性，对提高野胡萝卜籽精油的萃取率和拓展其应用领域具有现实的意义。本研究采用超临界CO₂萃取技术对野胡萝卜籽进行萃取，研究了不同萃取条件对野胡萝卜籽精油萃取率的影响，并进一步测试了野胡萝卜籽精油对多种植物病原真菌的抑菌效果。主要结果如下：1、利用Minitab软件分析萃取压力、萃取温度、萃取时间、夹带剂添加量及超临界CO₂流体循环量对萃取率的影响，确定萃取温度、萃取压力与夹带剂添加量三个因素为影响萃取率的显著因素。2、通过Minitab软件的CCD设计方案分析萃取压力、萃取温度、夹带剂添加量三因素对野胡萝卜籽精油得率的影响，得到超临界萃取工艺参数的回归方程为：Y=17.78﹣0.58X1﹣0.69X22＋0.66X3﹣1.15X1﹣1.06X22﹣0.36X23﹣0.63X1X2﹣0.60X1X3﹣0.86X2X3，方差分析结果表明拟合检验极显著，校正拟合度达0.9392，该方程能较好的预测野胡萝卜籽精油得率随各参数变化的规律。响应面法能较好地对野胡萝卜籽精油的超临界萃取工艺进行回归分析和参数优化。3、确定超临界CO₂萃取野胡萝卜籽精油优化后的最佳工艺条件：萃取压力13.46MPa、萃取温度40.16℃、夹带剂添加量为3.25%，野胡萝卜籽精油得率预测值为17.68%。4、通过生长速率法测定野胡萝卜籽精油对7种供试病原菌菌丝生长的抑制作用，结果表明在供试浓度范围内，野胡萝卜籽精油对供试菌菌丝生长均有不同程度的抑制效果，其对小麦赤霉病菌的抑制作用最强，其次为番茄叶霉病菌，其后依次为油菜菌核病菌、白菜黑斑病菌、苹果炭疽病菌、水稻稻瘟病菌、番茄灰霉病菌。5、通过凹玻片法测定野胡萝卜籽精油对6种病原菌孢子萌发的抑制作用，结果表明野胡萝卜籽精油对6种供试菌株孢子萌发的抑制效果与菌丝生长的抑制效果趋势基本一致。其对小麦赤霉病菌的抑制作用最强，其次为番茄叶霉病菌，其后依次为白菜黑斑病菌、苹果炭疽病菌、水稻稻瘟病菌、番茄灰霉病菌。不同菌株孢子萌发的抑制率均随精油浓度的增加而升高。此外，野胡萝卜籽精油能够有效抑制油菜菌核病菌的菌核萌发。更多还原

【Abstract】 Wild carrot （Daucus carota Linn.） commonly known as “heshicao and sha luobo”belongs to the family Apiaceae （Umbelliferae）, is widely distributed in many parts of theworld and its habitats include thickets, areas along railroads and roadsides, lawns, pasturesand other waste areas. Wild carrot seed oil is a slightly sweet, dry and earthy aroma and richin a variety of chemical constituents. However, its extraction process, especially the SFEextraction and antifungal effect are poorly understood. In this study, the supercritical fluidextraction （SFE） was applied for the extraction of essential oil from wild carrot （D. carotaLinn.） seeds, and the extraction process and its antifungal effect against phytopathogenicfungi were also studied.In this study, supercritical CO₂fluid extraction was applied to extracting the essential oilfrom wild carrot seeds （Daucus carota Linn）. The effect factors on the supercritical extractionwere determined. And the inhibitory effects of the essential oil were tested against mycelialgrowth and conidia germination of plant pathogens in vitro. The main results were as follows:1. The effect of extraction pressure, extraction temperature, extraction time, amount ofentrainer, and CO₂flow rate on the extraction rate were analyzed by the Minitab software andPB experiment. The results indicated that extraction pressure, extraction temperature, andamount of entrainer are the most important factor.2. The central composition design and response surface methodology were used toinvestigate the influence of three variables on the extraction rate of essential oil. The secondorder polynomial equation was found to give an adequate description describe the extractioncondition: Y=17.78﹣0.58X1﹣0.69X2＋0.66X3﹣1.15X12﹣1.06X22﹣0.36X32﹣0.63X1X2﹣0.60X1X3﹣0.86X2X3. The determination coefficient was R2=0.9392. These measures indicatethat the accuracy and general ability of the polynomial model are good and that analysis of theresponse trends using the model is reasonable.3. The optimum technological condition of extraction: extraction pressure13.46MPa,extraction temperature40.16℃, amount of entrainer3.25%. In this condition, the extractionrate of wild carrot seeds oil is17.68%.4. The antifungal effect of wild carrot seeds oil against various pathogens wasdetermined by measuring mycelial growth rate in vitro. The results indicated that the essential oil could inhibit the mycelial growth of7experimental strains. The order of EC50value is:Fusarium graminearum＜Fulvia fulva＜Sclerotinia sclerotiorum＜Alternaria brassicae＜Glomerella cingulata＜Pyricularia oryza＜Botrytis cinerea.5. The inhibitory effect of wild carrot seeds oil against conidia germination of6testedpathogens was conducted. The essential oil showed a strong inhibition effect on conidiagermination. The EC50value of essential oil on conidia germination is significantly differentamong different pathogens tested. The order of EC50value is: F. graminearum＜F. fulva＜A.brassicae＜G. cingulata＜P. oryza＜B. cinerea. Furthermore, the wild carrot seeds oil hadthe inhibitory effect on the sclerotia germination of S. sclerotiorum.更多还原