【作者】 苏茂文；

【导师】 罗万春；

【作者基本信息】 山东农业大学 ， 农药学， 2005， 硕士

【摘要】 马齿苋(Portulaca oleracea L.)系马齿苋科植物马齿苋的全草,是最常见的中草药之一。野生马齿苋具有很强的抑菌作用,临床上可用于治疗许多疾病。虽然在中草药学领域已有许多研究报道,但对于马齿苋防治农业害虫方面的研究比较少且缺乏系统性。本文以棉蚜(Aphis gossypiiGlover)作为靶标害虫,系统地研究了马齿苋中对棉蚜具有生物活性物质的提取、分离技术并初步探讨了该活性物质对棉蚜的作用方式,以期为进一步开发利用这一野生杀虫植物资源和未来仿生合成提供线索和理论依据。主要研究结果如下:1. 马齿苋提取物对棉蚜的毒杀活性。(1)马齿苋干样提取物对棉蚜的毒杀活性比同浓度的鲜样提取物高。利用9 种极性不同的溶剂采用冷浸法对马齿苋干样和鲜样分别制备提取物,结果表明,处理后48h,马齿苋干粉丙酮提取物对棉蚜的毒杀毒力最高, 其LC50为1.88mg/mL(干粉/mL,下同);在马齿苋鲜样提取物中以乙醇提取物对棉蚜的毒杀毒力最高, LC50为8.80mg/mL(鲜样/mL,下同)。(2)以马齿苋干粉为材料,甲醇为浸提溶剂,采用温浸法提取得到的粗提物对棉蚜的毒杀活性在所有提取物中是最高的,处理后48h 的LC50为1.19mg/mL。2. 马齿苋提取物对棉蚜的拒食活性。(1)马齿苋干样提取物对棉蚜的拒食活性比同浓度的鲜样提取物高。利用9 种极性不同的溶剂采用冷浸法对马齿苋干样和鲜样分别制备提取物,结果表明,处理后48h,马齿苋干粉石油醚提取物在浓度为25mg/mL时拒食率为81.20%,而马齿苋鲜样石油醚提取物在该浓度下对棉蚜的拒食活性仅为70.56%。(2)以马齿苋干粉为材料,石油醚为浸提溶剂,采用索氏提取法提取得到的粗提物对棉蚜的拒食活性在所有提取物中是最高的,其AFC50 为3.84mg/mL3. 马齿苋高毒杀活性提取物中最佳萃取组份的确定。对甲醇温浸法得到的马齿苋粗提物进行初步分离的实验结果表明,乙酸乙酯萃取物在4 种更多还原

【Abstract】 Recently more attention has been paid on products of natural plants whichplay a important role on encouraging sdudies of recent to organic synstheticinsecticides which is a serious threat to the environment such as resistance,residue and resurgence. In order to develop new ways and new natural productsfor controlling the vegetable pests and providing possible temples for thesynthetic of new “bioregulators”, a primary studies on extration, separation andbioassays of the active ingredient in Portulaca oleracea L extracts againstcotton aphis were made in this paperPortulaca oleracea L belongs to Portulacaceae and is one of Chinesetraditional herbal medicine plants. The wild P. oleracea has very strongbioactivity against fungi and bacteria and had been used to cure many diseasein clinic, but only a few researches focus on P. oleracea against the vegetablepests and especially are not systemic sdudies at the present time. RegardingAphis gossypii Glover as target pest , both the technic of distillment andseparation of the bioactive materials from the plant and the action way of thosebioactive materials to the Aphis gossypii Glover were studied systemically inpresent paper. The study provides the clue and theoretical basis for thedevelopment and utilization of this insecticidal plant in the future. The mainresults are as follows:1.Extracts of P. oleracea have a high contact toxicity to Aphis gossypiiGlover.(1) The contact toxicity to Aphis gossypii Glover of the extracts from thedried P. oleracea are higher than that from the fresh P. oleracea at the sameconcentration. Dried and fresh P. oleracea were extracted by cold-dippingmethod with nine different solvents and the results indicated that acetoneextract from the dried plant showed the highest contact toxicity with 1.88mg/mL (dried powder) of LC50 afer 48h; Ethanol extract from the fresh plant hadthe highest contact toxicity with 8.80mg /mL (fresh tissue) of LC50. (2)The extract distilled from dried P. oleracea by warm-dippingmethod with methanol has the highest contact toxicity(LC50=1.19mg/mL)among all the extracts. 2. Extracts of P. oleracea has a high antifeedant toxicity to Aphisgossypii Glover. (1)The antifeedant toxicity to Aphis gossypii Glover of the extractsfrom the dried P. oleracea are higher than that from the fresh P. oleracea at thesame concentration. dried and fresh P. oleracea were extracted by cold-dippingmethod with nine different solvents and the results indicated that petroleumether extract from the dried plant had antifeeding rate of 81.02% at theconcentration of 25mg/mL. Otherwise , petroleum ether extract from the freshplant only had antifeeding rate of 70.56% at the same concentration. (2)The extract distilled from dried P. oleracea by soxlet’s extractionmethod with petroleum ether has the highest antifeedant toxicity(AFC50=3.84mg/mL) among all the extracts. 3.The extract distilled from P. oleracea by warm-dipping method withmethanol had been crudely separated .The results indicated that ethyl acetateextract showed the highest contact toxicity in the four different extracts.Among the three concentration of 20,10 and 5mg/mL,ethyl acetate extract allshowed the highest contact toxicity to Aphis gossypii Glover and it’s adjustedmortality rate was 98.21%.Then the Trichloromethane extract and water extract.Petroleum ether extract had the lowest contact toxicity. 4.The extract distilled from P. oleracea by soxlet’s extraction methodwith Petroleum ether had been rudely separated .The results indicated thatBenzene extract showed the highest antifeedant toxicity in the four differentextracts. Among the three concentration of 5000, 2500 and 1250μg/mL,Benzene extract all showed the highest antifeedant toxicity to Aphis gossypii更多还原