9种植物提取物对植物病原真菌的生物活性筛选

以苹果腐烂病菌、小麦赤霉病菌、苹果轮纹病菌、棉花枯萎病菌、柑橘炭疽病菌和黄瓜枯萎病菌为供试菌种。采用菌丝生长速率法测定了9种植物乙醇提取物对6种植物病原真菌的抑制作用,结果表明,浓度为5mg/mL时,荆条花乙醇提取物对6种植物病原真菌均有一定程度的抑制作用,其中对苹果腐烂病菌、棉花枯萎病菌、苹果轮纹病菌和黄瓜枯萎病菌的抑菌率分别为91.07%、72.97%、64.54%和63.20%。采用抑制孢子萌发法测定了9种植物乙醇提取物对2种植物病原真菌的抑制作用,结果表明,浓度为20mg/mL时,雪松叶和仙鹤草叶乙醇提取物对黄瓜枯萎病菌和柑橘炭疽病菌的孢子抑制率为100%。     

穿破石抑菌活性初步研究

采用菌丝生长速率法测定了穿破石不同部位甲醇提取物对5种植物病原真菌的抑菌活性.结果表明:穿破石根提取物对梨锈病菌、稻瘟病菌、水稻纹枯病菌以及玉米炭疽病菌有很高的抑菌活性,质量浓度为10 g/L时,抑菌率分别为95.51%、99.39%、100.00%、86.11%;有效中浓度(EC50)分别为0.8031、0.9969、0.9812、0.9304 g/L.对柿角斑病菌的活性较低,质量浓度为10 g,L时,抑菌率为66.72%,EC50值为4.6539 g/L.茎叶提取物对上述5种病原菌的抑菌活性较低.采用固-液萃取法对穿破石抑菌活性成分进行了初步分离,结合活性跟踪,发现穿破石抑菌活性成分主要存在于乙酸乙酯萃取层中.     

放线菌发酵提取物对百合炭疽病的抗菌活性筛选

从云南不同生态环境中采集的土壤样品巾分离到334株放线菌，以百合炭疽病菌作为指示菌，通过菌株发酵提取物对孢子萌发抑制、菌丝生长抑制和温室盆栽防治效果的测定，初步筛选出对炭疽病菌分生孢子萌发有较强抑制能力的18个菌株，对炭疽病菌菌丝生长有较强抑制能力的24个菌株，离体叶片防治效果60％以上的14个菌株，其中YIM31927、YIM31047等10株发酵提取物对百合炭疽病菌孢子萌发、菌丝生长和离体叶片防治试验均表现出了一致活性，筛选到一批具有开发应用潜能的放线菌资源。     

落地生根叶乙醇提取物的抑真菌作用

采用菌丝生长速率法研究了落地生根叶乙醇提取物对9种植物病原真菌的抑制作用,同时采用菌丝生长速率和孢子萌发2种方法测定其对番茄早疫病菌的抑菌活性.结果表明:在200 g/L的质量浓度下,对9种植物病原真菌均有一定的抑制作用,抑制率达50%以上,其中对番茄早疫病菌抑制作用最强,抑制率达93.80%,对其孢子萌发的抑菌活性高于对其菌丝生长的抑菌活性,EC50值分别为38.70、28.97 g/L.     

海芋甲醇提取物的抑真菌作用

采用生长速率法测定了海芋的不同部分甲醇提取物对水稻纹枯病菌等15种植物病原真菌的生物活性。结果表明：海芋叶、茎和叶柄的甲醇提取物对荔枝霜疫霉病菌、稻瘟病菌和白菜黑斑病菌等有一定的活性；在10mg／mL的浓度下，海芋叶、茎和叶柄的甲醇提取物对水稻纹枯病菌菌丝生长的抑制率分别为53．45％、43．15％和41．14％；海芋叶甲醇提取物对水稻纹枯病菌的EC50值为8．52mg／mL。海芋叶甲醇提取物的石油醚、氯仿、乙酸乙酯和正丁醇萃取组分对水稻纹枯病菌的活性研究表明，氯仿层的活性最高，抑制率为89．12％。海芋叶甲醇提取物的氯仿萃取物对水稻纹枯病菌的EC50值为2．13mg／mL.     

八宝景天叶乙醇提取物的抑真菌活性

[方法]采用菌丝生长速率法研究了八宝景天叶乙醇提取物对9种植物病原真菌的抑制作用,同时采用菌丝生长速率和孢子萌发2种方法测定其对玉米弯孢病菌的抑菌活性。[结果]在质量浓度为200 g/L时,对9种植物病原真菌均有一定的抑制作用,且抑制率均达75%以上,其中对玉米弯孢病菌的抑制作用最强,抑制率为82.27%,对其孢子萌发的抑菌活性高于对其菌丝生长的抑菌活性,EC50值分别为74.18、66.53 g/L。[结论]八宝景天叶有着良好的抑菌效果,具有很好的开发价值。     

公、母丁香乙醇提取物离体抑菌活性比较

采用生长速率法和孢子萌发法测定了公丁香和母丁香的乙醇提取物对5种病原菌（番茄灰霉病菌、水稻稻瘟病菌、黄瓜炭疽病菌、苹果轮纹病菌和玉米小斑病菌）的菌丝生长和3种病原菌（番茄灰霉病菌、稻瘟病菌和玉米小斑病菌）孢子萌发的影响。结果表明，提取物对两者均有一定的抑制作用：对于同一种病原菌来说，丁香的乙醇提取物对其孢子萌发的抑制效果好于对其菌丝生长的抑制效果；在相同的供试浓度下，公丁香的抑菌效果优于母丁香。     

落地生根萃取物的抑菌活性

[目的]比较落地生根根、茎、芽和花各萃取相提取物的抑菌活性,进一步明确起抑菌作用的活性成分,为以后的分离打下基础.[方法]以番茄早疫病菌、水稻立枯病菌为指示菌,采用生长速率法和孢子萌发法,测定各自的抑菌活性.[结果]落地生根芽氯仿萃取物对2种菌的菌丝生长和孢子萌发具有较好的抑制作用,菌丝生长抑制率分别为92.41%和89.22%,孢子的萌发抑制率依次为91.85%、86.11%.[结论]芽氯仿相萃取物的抑菌效果最好,表明落地生根植物中起抑菌作用的活性成分主要集中在芽部位,且抑菌活性成分主要为弱极性物质.     

白果外种皮中银杏酚酸提纯及其抑菌活性初探

从白果外种皮中提取纯化银杏酚酸，并对其抑菌作用进行初步研究。采用正交实验筛选加热回流提取条件，有机溶剂萃取结合柱层析方法分离纯化银杏酚酸，生长速率法测定银杏酚酸对植物病原真菌菌丝抑制率。加热回流提取参数：提取溶剂为甲醇，40℃，料液比为1∶12,90 min；经乙酸乙酯萃取、脱酸树脂柱层析纯化，获得80.96%含量银杏酚酸；对5种植物病原真菌均有抑制作用，含量为0.293 mg/m L时对月季炭疽病菌（Colletotrichum boninense）抑制率为49.09%、对杜鹃炭疽病菌（C.fioriniae）为30.30%、对石榴干腐病菌（Coniella granati）为23.26%、对葡萄炭病疽菌（C. gloeosporioides）为21.70%和对烟草枯萎病菌（Fusarium redolens）为21.01%。结果表明，提纯工艺把白果外种皮中8%银杏酚酸提高至80.96%，确定银杏酚酸可较好抑制月季炭疽病菌菌丝生长。     

5种中药提取物对人参黑斑病菌的抑制作用

采用生长速率法测定了苦参、黄连、丁香、藿香、细辛5种中药提取物对人参黑斑病菌的生物活性.研究结果表明:在质量浓度为1.0 kg/L下,丁香、藿香和苦参对人参黑斑病菌的菌丝生长抑菌率达100%、92.2%和89.2%;丁香最小抑制质量浓度为0.0625 kg/L,藿香和苦参分别为0.125 kg/L和0.5 kg/L.     

紫茉莉根中油脂化合物的气相色谱-质谱分析

为鉴定紫茉莉根的油脂化合物化学成分,采用气相色谱-质谱联用仪分析了新鲜紫茉莉根中和干燥紫茉莉根中的油脂类化学成分,采用锋面积归一化法测定其相对含量。结果表明,从紫茉莉新鲜根中分离得到9种化合物,主要为脂肪酸及其酯、烷烃等化合物。从紫茉莉干燥根的乙醇提取物中分离得到7种化合物,主要为醛类、脂肪酸及其酯等化合物。     

Composition and Characteristics of Mirabilis jalapa Seed Oil

Mirabilis jalapa, an evergreen garden flowering shrub bears black oil-bearing pepper like oval shaped seeds. On extraction the seeds yielded only 3.0% of oil of 0.70 g/ml density, 26.10 dynes/cm surface tension and 169.5 millipoise viscosity at 20.5° C. The determined iodine value was 80 and saponification value 172. The G.L.C. analysis showed a high oleic content.     

几种植物的杀虫活性初探

首次报道黄连（根）和菟丝子（种子）的杀虫活性。用1％浓度的甲醇提取物处理试虫后，所筛选的植物巾菟丝子种子和李叶绣线菊茎的甲醇提取物对家蝇48h的毒杀作用强，分别为100．00％和75．86％，单面针叶和阔叶十大功劳茎叶也有较好的毒杀作用，分别为58．62％和67．86％。黄连根甲醇提取物24h和大叶醉鱼草茎叶甲醇提取物48h对亚洲玉米螟3龄幼虫的拒食率分别为76．48％和76．50％，且出现虫体细且短小、头部宽大、与腹部极不对称和化蛹延迟现象，大黄和阔叶十大功劳也表现出一定的毒杀或拒食或抑制生长发育现象。所筛选的特有植物对赤拟谷盗种群的毒杀作用和繁殖抑制作用较低。毒杀作用最强的为大叶醉鱼草茎叶，处理后30d，赤拟谷盗的死亡率为40．16％，繁殖抑制率最强的为黄连根，处理后60d，繁殖抑制率为46．38％。以甲醇冷浸提取法对所采集的植物材料进行冷浸提取时，提取率分布在1．41％～7．06％之间。     

Studies on Mirabilis jalapa (Four O'clock Plant) Seed Oil

Mirabilis jalapa of Nyctaginaceae plant family yields 4–5% of fatty oil. The oil is investigated for its glycerides and fatty acid composition by gas liquid chromatography. The fatty acids in the seed oil constitute C_16:0, 18.3%;C_18:1,55.3%;C_18:2,11.5%;C_18:3,14.9%. The triglyceride components were also determined by separating the triglycerides according to their degree of unsaturation by means of thin-layer chromatography on silica gel impregnated with silver nitrate. The fatty acid composition of the different triglyceride fractions was determined. Moreover, the triglycerides were separated according to their carbon number by gas liquid chromatography.     

Allelopathic effects of water extracts ofArtemisia princeps var.orientalis on selected plant species

The allelopathic effects of wormwood plants (Artemisia princeps var.orientalis) and their possible phytotoxicity on receptor species were investigated. The aqueous extracts of mature leaf, stem, and root of wormwood plants caused significant inhibition in germination and decreased seedling elongation of receptor plants, whereas germination of some species was not inhibited by extracts of stems and roots. Dry weight growth was slightly increased at lower concentrations of the extract, whereas it was proportionally inhibited at higher concentrations. The calorie value of the organic matter in receptor plants measured by bomb calorimeter was reduced proportionally to the extract concentration. However, results with extracts of juvenile leaf did not correlate with inhibition or promotion of elongation and dry weight.     

厚果鸡血藤提取物对两种同翅目害虫的生物活性

测定了厚果鸡血藤种子和根提取物对褐飞虱和桃蚜两种同翅目害虫的生物活性,结果表明,它们对这两种害虫有很高的触杀活性,对桃蚜有一定的胃毒活性。用不同溶剂提取时,三氯甲烷提取物的活性明显高于甲醇提取物的活性。用相同溶剂提取时,种子提取物的活性比根提取物活性高。对褐飞虱、桃蚜的触杀活性及对桃蚜的胃毒活性均以种子三氯甲烷提取物最高,种子三氯甲烷提取物对褐飞虱、桃蚜的接触LD50值分别为0.25、0.03g/头,对桃蚜的胃毒LC50值为1342mg/L。四种提取物对两种害虫的毒力顺序为:种子三氯甲烷提取物>根三氯甲烷提取物>种子甲醇提取物>根甲醇提取物。     

石菖蒲根茎提取物对粘虫的生物活性

用石菖蒲的甲醇、石油醚、水等6种不同极性溶剂的提取物对粘虫进行了室内生物活性测定。结果表明：石菖蒲的甲醇提取物对粘虫具有极强的拒食和生长发育抑制作用，兼具一定触杀活性。在非选择性条件下，石菖蒲甲醇提取物对粘虫4龄幼虫拒食率高达91．89％，拒食活性显著高于其它提取物；在毒杀和生长发育抑制试验中，取食含毒叶片后的4龄幼虫体重在3d内出现负增长，4d后试虫全部死亡；此外，石菖蒲甲醇提取物对粘虫幼虫也有一定触杀活性，其死亡率超过60％。在该试验中，石油醚提取物对粘虫幼虫的拒食活性仅次于甲醇提取物，而对粘虫的生长抑制作用则低于甲醇、氯仿及乙酸乙酯3种溶剂的提取物。6种不同极性溶剂提取物中，以水提取物对粘虫的生物活性最小。     

Phytotoxicity of water-soluble substances from alfalfa and barley soil extracts on four crop species

Problems associated with continuously planting alfalfa (Medicago saliva L.) or seeding to thicken depleted alfalfa stands may be due to autotoxicity, an intraspecific form of allelopathy. A bioassay approach was utilized to characterize the specificity and chemical nature of phytotoxins in extracts of alfalfa soils as compared to fallow soil or soil where a cereal was the previous crop. In germination chamber experiments, water-soluble substances present in methanol extracts of soil cropped to alfalfa or barley (Hordeum vulgare L.) decreased seedling root length of alfalfa L-720, winter wheat (Triticum aestivum L. Nugaines) and radish (Raphanus sativa L. Crimson Giant). Five days after germination, seedling dry weights of alfalfa and radish in alfalfa soil extracts were lower compared to wheat or red clover (Trifolium pralense L. Kenland). Growth of red clover was not significantly reduced by soil extracts from cropped soil. Extracts of crop residue screened from soil cropped to alfalfa or barley significantly reduced seedling root length; extracts of alfalfa residue caused a greater inhibition of seedling dry weight than extracts of barely residue. A phytotoxic, unidentified substance present in extracts of crop residue screened from alfalfa soil, which inhibited seedling root length of alfalfa, was isolated by thin-layer chromatography (TLC). Residues from a soil cropped continuously to alfalfa for 10 years had the greatest phytotoxic activity.     

Supercritical Carbon Dioxide Extraction of Bioactive Compounds from Ampelopsis grossedentata Stems: Process Optimization and Antioxidant Activity

Supercritical carbon dioxide (SC-CO(2)) extraction of bioactive compounds including flavonoids and phenolics from Ampelopsis grossedentata stems was carried out. Extraction parameters such as pressure, temperature, dynamic time and modifier, were optimized using an orthogonal array design of L(9) (3(4)), and antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and ferrous ion chelating (FIC) assay. The best conditions obtained for SC-CO(2) extraction of flavonoids was 250 bar, 40 °C, 50 min, and with a modifier of methanol/ethanol (1:3, v/v), and that for phenolics extraction was 250 bar, 40 °C, 50 min, and with a modifier of methanol/ethanol (1:1, v/v). Meantime, flavonoids and phenolics were found to be mainly responsible for the DPPH scavenging activity of the extracts, but not for the chelating activity on ferrous ion according to Pearson correlation analysis. Furthermore, several unreported flavonoids such as apigenin, vitexin, luteolin, etc., have been detected in the extracts from A. grossedentata stems.     

两种万寿菊提取物对枣尺蠖毒杀效果

以万寿菊根为材料，以水为对照，分别用甲醇、氯仿作溶剂进行索氏提取，并用提取液对枣尺蠖幼虫进行杀虫生物活性测定，结果表明：氯仿提取物的毒力比甲醇提取物的毒力强；同时。在光照条件下，甲醇提取物、氯仿提取物对幼虫的毒力都比无光照条件下显著。