茜草对枸杞蚜虫的杀虫活性初探

采用点滴法,测定了茜草乙醇提取物和石油醚、氯仿、乙酸乙酯、正丁醇和水5种不同极性萃取物对枸杞蚜虫的触杀活性.结果表明:95%乙醇提取物对枸杞蚜虫有较高的触杀活性,而且随着提取物质量浓度的增大和处理时间的延长,枸杞蚜虫的校正死亡率都在升高.质量浓度为50.00 g/L时,48 h的校正死亡率达97.62%,LC50值2.633 g/L.5种萃取物对枸杞蚜虫杀虫活性的顺序为石油醚＞氯仿＞乙酸乙酯＞正丁醇＞水,石油醚萃取物48 h的校正死亡率69.05%.     

龙葵绿果对小菜蛾的杀虫活性初探

采用浸渍法,测定了龙葵绿果乙醇提取物和石油醚、氯仿、乙酸乙酯、正丁醇、水5种不同极性溶剂萃取物对小菜蛾的触杀活性.结果表明:95%乙醇提取物对小菜蛾有较高的触杀活性,而且随着提取物质量浓度的增大和处理时间的延长,小菜蛾的校正死亡率升高.质量浓度为50.00 g/L时,72 h的校正死亡率达到97.62%,LC50值4.798 g/L.5种萃取物对小菜蛾杀虫活性主要集中在石油醚和氯仿萃取部分,石油醚和氯仿萃取物72 h的校正死亡率分别为83.33%和73.33%.     

荆条乙醇提取物对植物病原真菌的抑菌活性初步研究

探索荆条的抑菌活性,为综合开发利用提供科学依据。采用生长速率法测定了荆条花和叶的乙醇提取物以及各萃取物对植物病原真菌的抑制作用。结果表明:荆条花乙醇提取物的抑菌活性好于叶。当供试质量浓度为5.0 g/L时,花的乙醇提取物对苹果腐烂病菌、白菜黑斑病菌、番茄早疫病菌和棉花枯萎病菌的抑菌率分别为87.72%、77.32%、72.69%和71.37%。荆条花乙醇提取物不同溶剂萃取物中,石油醚和乙酸乙酯的抑菌活性较高。石油醚萃取物和乙酸乙酯萃取物对苹果腐烂病菌的EC50值分别为0.32 g/L和0.23 g/L;石油醚萃取物和乙酸乙酯萃取物对白菜黑斑病菌的EC50值分别为0.45 g/L和0.20 g/L。石油醚萃取物是进一步研究的重点。     

香椿子化学成分鉴别研究

初步研究香椿子不同萃取部位的化学成分类别,为后续分离纯化提供理论依据。对香椿子水、乙醇提取物进行理化鉴别研究;对75%乙醇提取物的石油醚、乙酸乙酯、正丁醇、水萃取部位进行PC法与TLC法、UV法鉴别研究。结果表明:证实香椿子中含有酚类、生物碱、甾体三萜、挥发油、香豆素、黄酮、皂甙、糖类等化学成分。对香椿子中化学成分类别进行了鉴别研究,可为下一步香椿子资源开发与综合利用奠定基础。     

真菌发酵虻虫活性物质提取、分离及含量测定

通过超声水提法提取发酵虻虫干粉中水溶性总蛋白,利用改良Lowry法测定其含量;并采用80%乙醇回流提取的方法提取总黄酮,并通过石油醚、乙酸乙酯分别萃取,同时通过NaNO_2-AlCl_3-NaOH比色法测定发酵虻虫粉不同极性部位中总黄酮的含量。结果表明发酵后虻虫粉中水溶性总蛋白的平均含量高达99.3140mg/g,而在醇提物中水部总黄酮含量明显高于石油醚部和乙酸乙酯部。     

爬山虎茎秆白藜芦醇粗提物的萃取纯化研究

有机溶剂萃取法提纯是低含量提纯常用的方法。本文实验选择了爬山虎茎秆粗提物中萃取白藜芦醇的萃取剂为乙醚和乙酸乙酯,乙酸乙酯优于乙醚;乙酸乙酯萃取最佳参数为9.658g/kg白藜芦醇浸提物0.5g,1 m L95%乙醇,2 m L水,4 m L,萃取物纯度最高为28.86g/kg。     

细穗兔儿风挥发油化学成分分析

细穗兔儿风Ainsliaea spicata干燥全草的95 %工业乙醇提取物,用石油醚萃取,浓缩后上硅胶柱层析,V (石油醚) / V (乙酸乙酯) 为60∶1洗脱,即得到其挥发油成分.用GC-MS 联机手段进行分析,鉴定了15 个化合物 ,并采用线性归一方法测定各化学成分的相对含量.     

牛皮消对小菜蛾的活性测试及活性成分分析

采用点滴法测试了牛皮消乙醇提取物及其不同极性溶剂萃取物和柱层析分离物对小菜蛾3龄幼虫的触杀活性.结果表明:牛皮消乙醇提取物对小菜蛾3龄幼虫72 h的毒力(LC50)为2.13 g/L.强于辛硫磷(3.93 g/L)、敌敌畏(4.36 g/L)、高效氯氟氰菊酯(4.51 g/L);牛皮消乙醇提取物的不同极性溶剂萃取物对小菜蛾3龄幼虫的触杀活性顺序为石油醚(97.95%)>氯仿(42.17%)>乙酸乙酯(28.57%)>水(18.37%)>正丁醇(11.53%);石油醚萃取物多级柱层析分离物对小菜蛾触杀活性较高部分的GC-MS检测结果显示含量最高的物质为甾醇类(18.26%)、麦角甾烷类(16.69%)和β-谷甾醇(15.35%).     

白苞蒿化学成分预试研究

通过试管反应法或纸反应法分别对白苞蒿药材的水、95%乙醇、乙酸乙酯和石油醚提取液进行沉淀反应或颜色反应,采用光谱法对白苞蒿95%乙醇提取液进行理化鉴别。初步推断白苞蒿中可能含有氨基酸、多肽、蛋白质,糖、多糖、苷类,皂苷,有机酸,黄酮类,酚类,内酯、香豆素类,甾体、三萜类,生物碱,挥发油等成分。为进一步研究白苞蒿药材的化学成分提供科学依据。     

补骨脂有效成分提取工艺的研究

目的:筛选并优化中药补骨脂的提取方法。方法:以补骨脂素、异补骨脂素含量为考察指标,采用单因素实验,分别对提取溶剂(乙醚、石油醚、乙酸乙酯、95%乙醇、85%乙醇、70%乙醇、水等)和提取方法(回流提取、超声提取、连续回流提取)进行考察,应用高效液相色谱进行含量测定,得到最适宜的提取方法。结论:85%乙醇回流提取两小时为最佳提取工艺。     

肿柄菊粗提物对线虫毒杀活性的研究

为评价肿柄菊粗提物毒杀线虫的潜力,利用石油醚、乙酸乙酯、二氟甲烷浸泡粉碎的肿柄菊枝叶混合物,经旋转蒸发获得粗提物,通过浸渍法检测了不同粗提物的毒杀线虫活性。结果表明：当浓度为10mg·mL^-1时,石油醚、乙酸乙酯和二氟甲烷粗提物24～72h内对线虫的毒杀效果较弱;当浓度为20mg·mL^-1时,二氯甲烷粗提物毒杀线虫活性最好,处理72h的线虫校正死亡率可达50．6％,乙酸乙酯粗提物和石油醚粗提物毒杀线虫活性均较弱;当浓度为40mg·mL^-1时,毒杀线虫活性大小依次是乙酸乙酯粗提物〉石油醚粗提物〉二氯甲烷粗提物,其中乙酸乙酯粗提物处理72h的线虫校正死亡率达73．6％。表明,对肿柄菊粗提物进行合理的处理、分离、纯化,有望开发出高效低毒、绿色环保的新型杀线虫农药。     

甘草抗氧化物的提取工艺

对甘草甜素提取后的废渣,分别用不同浓度的乙醇进行粗提,通过活性跟踪检测,筛选出60%乙醇提取物活性最好;再用石油醚、乙酸乙酯进行梯度提取,确定乙酸乙酯提取物的活性更优,测得总黄酮含量为27.73%。并通过实验证明,该提取物与其他抗氧化剂复配后其活性均好于单个抗氧化剂。     

Sterols and Stanols in Foods and Dietary Supplements Containing Added Phytosterols: A Collaborative Study

An international, multilaboratory collaborative study was carried out to evaluate the performance of Official Method Ce 12‐16 of the American Oil Chemists’ Society (AOCS) for the determination of plant sterols and stanols, collectively referred to as phytosterols, in foods and dietary supplements containing added phytosterols and in the phytosterol food additive concentrates used to prepare such products. AOCS Official Method Ce 12‐16 involves the extraction of free sterols/stanols and saponified steryl/stanol esters followed by the gas chromatographic separation and flame ionization detection of phytosterol trimethylsilyl ether derivatives. A total of 14 laboratories from six countries successfully completed the analysis of collaborative samples of foods (e.g., baked goods, beverages, margarines; n = 9), dietary supplements (n = 5), and phytosterol concentrates (n = 4). Study results for the contents of total phytosterols (weight/weight) were 0.19–8.4% for foods, 8.7–49% for dietary supplements, and 57–97% for concentrates. AOCS Official Method Ce 12‐16 showed acceptable performance for total and individual phytosterols, indicating that this method was suitable for the determination of added phytosterols in a wide variety of market products and concentrates. AOCS Official Method Ce 12‐16 is appropriate for the determination of the five major phytosterols (i.e., campesterol, stigmasterol, β‐sitosterol, campestanol, and sitostanol) that are the subject of the United States Food and Drug Administration's health claim for phytosterols and the reduced risk of coronary heart disease.     

黑果腺花楸不同极性物质抗氧化及抗炎镇痛研究

为了高效的提取及分离黑果腺花楸活性物质,以黑果腺花楸为原料,不同极性溶剂作为溶媒(石油醚、乙酸乙酯、正丁醇和水),采用超声波辅助提取法,分别提取到不同极性物质(石油醚相、乙酸乙酯相、正丁醇相和水相)。利用不同的抗氧化模型(铁还原力、清除羟基自由基(OH)·能力、清除ABTS自由基能力、抗肝组织自发性脂质过氧化能力和花生油氧化能力)、炎症模型(小鼠耳廓肿胀和小鼠肉芽肿胀)和镇痛模型(小鼠热板痛阈值和冰醋酸致小鼠扭体次数)来评价黑果腺花楸不同极性物质的活性。结果表明,正丁醇相具有较强的抗氧化能力和消炎镇痛能力。正丁醇可以作为提取黑果腺花楸活性物质及分离抗氧化活性及抗炎镇痛成分的溶剂。     

凤眼草抑菌活性成分的研究

对苦木科臭椿属植物臭椿的果实凤眼草(Ailanthus altissima)的95％乙醇提取液的抑菌活性进行了研究.利用系统溶剂萃取法得到了石油醚提取物、氯仿提取物、乙酸乙酯提取物和正丁醇提取物,重点研究了4种提取物对枯草芽孢杆菌、大肠杆菌和金黄色葡萄球菌的抑菌性和最低抑菌浓度.结果表明,乙酸乙酯提取物和正丁醇提取物均...     

Oil Phytosterol Concentration in Sunflower Presents a Dilution Response with Oil Weight per Grain

Phytosterols are plant sterols that present several benefits for human health. In crop species, such as sunflower, oil phytosterol concentration shows genetic and environmental variations. The reasons that cause such varied concentration of phytosterols in the oil are unknown. The aim of this work was to investigate the relationships between phytosterol concentration and composition and grain oil content in sunflower. Two sets of samples, with lines and hybrids grown in different environments in Argentina and Spain, were used to establish and validate the relationships between phytosterols and grain oil content. Oil phytosterol concentration decreased in both types of genotypes, lines, and hybrids, when oil content per grain increased. A dilution-like relationship accounted for 82% of the variability in phytosterol concentration among genotypes and environments. Phytosterol concentration rapidly increased with oil contents lower than 11.4 mg per grain. This relationship was observed for total phytosterols and each type of the phytosterols analyzed. With low oil per grain, phytosterol composition varied, with higher proportions of β-sitosterol and Δ⁷-stigmastenol. The relationships established in this work could serve to design breeding and crop management strategies.     

Analysis of free and esterified sterols in vegetable oils

In vegetable oils, phytosterols occur as free sterols or as steryl esters. Few analytical methods report the quantification of esterified and free sterols in vegetable oils. In this study, esterified and free sterols were separated by silica gel column chromatography upon elution with n-hexane/ethyl acetate (90∶10 vol/vol) followed by n-hexane/diethyl ether/ethanol (25∶25∶50 by vol). Both fractions were saponified separately and the phytosterol content was quantified by GC. The analytical method for the analysis of esterified and free sterols had a relative standard deviation of 1.16% and an accuracy of 93.6–94.1%, which was comparable to the reference method for the total sterol analysis. A large variation in the content and distribution of the sterol fraction between different vegetable oils can be observed. Corn and rapeseed oils were very rich in phytosterols, which mainly occurred as steryl esters (56–60%), whereas the majority of the other vegetable oils (soybean, sunflower, palm oil, etc.) contained a much lower esterified sterol content (25–40%). No difference in the relative proportion of the individual sterols among crude and refined vegetable oils was observed.     

Profile of Bioactive Compounds in Avocado Pulp Oil: Influence of the Drying Processes and Extraction Methods

The influence of different procedures of pulp drying and oil extraction methods on the concentrations of α-tocopherol, squalene and several phytosterols in avocado oil was evaluated. Pulp portions of Fortune variety avocados were dried either by lyophilization or under circulating air at 40 or 70 °C. For lyophilization and for each air drying temperature, the oil was obtained either by cold pressing or with Soxhlet extraction using petroleum ether. The dehydrated pulp (73 % of the pulp weight) yielded 25–33 % oil by cold pressing, and 45–57 % oil by Soxhlet extraction. Infrared spectroscopy and gas chromatography with FID and mass spectrometry detection were used to analyze the oils. α-Tocopherol, squalene, cycloartenol acetate, β-sitosterol, campesterol and stigmasterol were present in all the oil samples. In comparison to lyophilization, hot air drying resulted in smaller concentrations of α-tocopherol, squalene and β-sitosterol, and larger relative concentrations of campesterol and cycloartenol acetate. On the other hand, extraction by cold pressing produced a smaller amount of oil, with greater concentrations of α-tocopherol and squalene, and lower contents of campesterol and cycloartenol acetate, than Soxhlet extraction. Thus, the oil yield was maximal with lyophilization and Soxhlet extraction, but lyophilization and cold pressing produced oils which had greater concentrations of antioxidants and other bioactive compounds.     

海南核果木抗氧化活性研究

将海南核果木干燥枝叶用乙醇浸提,对总提物分别用石油醚、乙酸乙酯、正丁醇萃取,并以DPPH法和FRAP法对总提物及各萃取物的抗氧化活性进行评价。结果显示,在DPPH法中海南核果木总提物(DH)、石油醚萃取物(DHMSO)、乙酸乙酯萃取物(DHEtOAC)、正丁醇萃取物(DHNBA)、水相(DHH2O)的IC50分别为77.3、115.2、51.4、342.9、205.7 mg/L,其FRAP值分别为(11 712.2±931.8)、(10 820.9±690.5)、(14 386.4±568.8)、(1 157.6±63.3)、(5 584.1±182.3)μmol Fe2+/g。且抗坏血酸(Vc)和BHT的IC50分别为10.7、47.1mg/L,FRAP值分别为(18 022.8±63.3)、(14 568.7±137.0)μmol Fe2+/g,并通过多元聚类分析表明DH、DHMSO、DHEtOAC与BHT、Vc具有类似强度的抗氧化活性,可归为同一类型,且DHEtOAC抗氧化活性与BHT无显著性差异,说明其粗提物具有较强的抗氧化活性。     

正交设计优化青荚叶中植物甾醇的提取工艺

运用皂化法提取青荚叶中植物甾醇化合物（以豆甾醇的含量为指标）,考察料液比、碱浓度、皂化时间、萃取剂用量对提取工艺的影响.结果表明,最佳提取工艺条件为：料液比1∶6（g/mL）,碱浓度10％,皂化时间90 min,萃取剂用量60 mL.建立的青荚叶甾醇皂化提取物的提取方法稳定可靠,具有快速、精密度高及重现性好且操作简单等优点,可作为青荚叶中植物甾醇提取的最佳工艺.