共查询到19条相似文献，搜索用时 468 毫秒
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在室温下用间歇式快速搅拌法从印楝种仁中浸提印楝油和印楝素。讨论了料液比以及浸提时间对得率的影响。结果表明:印楝种仁300g,以750mL石油醚做溶剂,在快速搅拌条件下浸提21min时印楝油得率最高;将300g去油后的印楝种仁以900mL甲醇做溶剂,在快速搅拌下浸提21min时印楝素得率最高。由此得出,快速搅拌法浸提印楝油的最佳条件是:溶剂石油醚、料液比1∶2.5(g∶mL,下同)、时间每次7min、浸提3次,出油率30.4%;快速搅拌法浸提印楝素的最佳条件是:溶剂为甲醇、料液比1∶3、时间每次7min、浸提3次,印楝素A的得率为0.438%,印楝素B的得率为0.142%。 相似文献
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微波辅助法提取印楝素的研究 总被引：21，自引：3，他引：21
介绍了一种有效利用微波辅助从印楝(Azadirachta indica A.Juss)种仁中提取印楝素的方法。通过考察辐射时间、溶剂、物料比以及辐射功率等因素对提取率的影响，得出结论为：预处理过的印楝种仁粉末6.65g(相当于印楝种仁10g)，以甲醇做溶剂、微波功率210w、物料比1：3(g／mL)、辐射时间为3min*3次，提取率最高。与传统的磁搅拌法相比，该方法不仅工艺简单，而且可以提高产率，缩短提取时间。用高压液相法定量地测定了所提取印楝素的含量，其提取率可达0．519％． 相似文献
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超声波用于强化有机溶剂提取印楝素 总被引：20，自引：6，他引：20
研究了用超声波强化有机溶剂提取印楝素的工艺过程，分别考察溶剂、料液比、超声波作用时间、超声波功率对提取率的影响实验发现，较理想的提取条件为：13．3g印楝种仁粉，料液比1：2，超声波功率200W；超声波作用时间与溶剂有关。甲醇15min、乙醇20min、乙酸乙酯10min；3种溶剂较佳提取率分别为0．3786％、0．3658％、0．2462％提取样晶利用高效液相色谱仪采用外标法测定提取物中印楝素的含量。实验结果表明，超声波强化提取与搅拌提取相比，不仅缩短了提取时间，而且提取率有所提高。 相似文献
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对印楝素含量与种子形态表征及成熟期的关系进行了初步研究.种子的长宽比与印楝素含量相关,并且认为它是能反映印楝素含量的主要表征,得出种子长宽比(X)与印楝素含量(Y)的关系为:Y=0.295 0.134X-0.028X2.种子长宽比接近2.39时,种仁的印楝素含量出现峰值,可将印楝种子的形态表征作为初步估测印楝素含量的指示参数,而种子的成熟期与印楝素含量无关.在印楝原料林良种优良母树筛选中应尽量选择各个种源中生长良好、结实量大、种子饱满且长宽比接近2.39的植株. 相似文献
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[目的]建立一套适合印楝药用优树无性系测定的分析评价方法,并进行农药型印楝优株评价。[方法]以印楝药用优树和平均木无性系为试验材料,通过不完全谱系设计建立无性系品比试验,采用重复力估算法在表型水平上对无性系当代种子农药品质性状进行遗传变异分析,提出"农药型印楝"的概念和标准,根据该标准进行农药型印楝优株评价。[结果]无性系种子印楝素组分含量随优树种子印楝素组分含量的变化而变化,但在无性系内和无性系间都存在不同程度变异:同一无性系各分株间的印楝素B变异(5.26%37.55%)较印楝素A变异(6.06%15.80%)和印楝素AB变异(2.95%16.14%)大,印楝素B和印楝素AB几乎呈退化和/或趋中遗传倾向,而印楝素A则既有退化和/或趋中遗传倾向又有超母遗传倾向;无性系间种子印楝素组分含量性状具有异质性(P0.01)。无性系印楝素A重复力(0.78)、印楝素B重复力(0.81)和印楝素AB重复力(0.83)均较高,表明无性系间印楝素组分含量的差异主要是由遗传效应和一般环境效应造成的,受特殊环境效应影响较小。按农药型印楝标准,评定LD0505、WW0401、AT0515三个无性系为"农药型印楝品种",LD0505和WW0421是"农药型印楝亲本"。[结论]重复力估算法适用于印楝药用优树无性系测定的分析评价,优树种子农药品质性状的遗传传递力强,无性系能保持优树农药品质的优良特性;评定LD0505、WW0401、AT0515为农药型印楝品种,LD0505和WW0421还可作为农药型印楝亲本,其余优树无性系不宜选择。 相似文献
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超声法提取薏苡仁油的工艺研究 总被引：1，自引：0，他引：1
采用超声波法提取薏苡仁油,对其中的影响因素提取溶剂、药材粒径、提取时间、提取温度、料液比等进行系统研究。结果表明：将薏苡仁药材粉碎至粒径60目,按料液比1∶3．5加入无水乙醇为提取溶剂,在60℃温度下提取40 min ,所得提取率最高为11．8％。该提取工艺具有提取时间短,效率高,节省溶剂的特点。 相似文献
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The repellent effect of 3 different neem formulations was tested on red locust,Nomadacris septemfasciata Serv., in a maize field in the southwest of madagascar. A simple water extract from neem seed kernels (200 l and 600 l per ha), an enriched neem ULV-formulation (2 l per ha) and a dust, prepared on the base of neem seed cake (5 kg per ha) were applied. All four treatment provided protection from attack for at least five days. The water extract was significantly active until 7 days, the neem-ULV-formulation until 9 days after treatment. The application of neem seed kernel water extract could be a simple means for Malagasy farmers to protect their fields against red locust.
N. septemfaxciata is a very interesting test organism because it is much easier to work with this species compared to the taxonomical closely related desert locust (Schistocerca gregaria Forsk.).
With 1 figure 相似文献
Zusammenfassung Drei verschiedene Niemprodukte wurden auf ihre fraßabschreckende Wirkung auf die rote WanderheuschreckeNomadacris septemfasciata in einem Maisfeld im Südwesten Madagaskars überprüft. Ein einfacher Wasserextrakt aus 50 g gemahlenen Niemsamen pro Liter wurde in zwei Applikationsvolumina (200 l und 600 l pro ha) gespritzt. Eine angereicherte Niem-ULV-Formulierung wurde mit Hilfe eines ULV-Spritzgerätes bei 2 l/ha appliziert. Fünf kg aus Niempreßkuchen hergestellter Puder pro ha wurde ebenfalls ausgebracht. Alle 4 Behandlungen schützten den Mais mindestens für 5 Tage vor Fraßschäden durchN. septemfasciata. Der Wasserextrakt verminderte den Befall über 7 Tage und die Niem-ULV-Formulierung über 9 Tage signifikant. Der leicht herzustellende Wasserextrakt könnte ein für die Maisbauern geeignetes Mittel sein, um ihre Felder vor dem Befall vonN. septemfasciata wirksam zu schützen. Da es auf Grund ihrer Biologie viel einfacher ist, mitN. septemfasciata als mit der taxonomisch sehr eng verwandten Wüstenheuschrecke (Schistocerca gregaria Forsk.) zu arbeiten, eignet sichN. septemfasciata hervorragend als Modellorganismus für Versuche mit Niemprodukten im Freiland.
With 1 figure 相似文献
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Prof. Dr. Nadia Z. Dimetry A. A. Gomaa A. A. Salem A. S. H. Abd-El-Moniem 《Journal of pest science》1996,69(6):140-141
The bioactivity of different formulations of neem seed extracts against the whiteflyBemisia tabaci (Genn.) was assayed in semifield trials during 1992. Tomato plants variety UC-97 were cultivated in pots and left to natural infestation with whitefly in an open field and sprayed with various concentrations of each extract. The high concentrations of all the extracts tested exhibited obvious activity. Also, the different treatments reduced the population density of the adult whiteflies compared with the control. The percentage reduction in the population reached its maximum level one hour after treatment with any tested extract.With one table 相似文献
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Termite feeding behavior and the chemoreception of plant extracts were evaluated to investigate the water extracts from akamatsu
(Pinus densiflora), neem (Azadirachta indica), and their equivalent mixture using pseudoergates of Zootermopsis nevadensis. In behavioral assays, termite preference was akamatsu > akamatsu plus neem > neem. Electrophysiological recordings from
the taste hairs on labial palps showed vigorous impulse discharge to akamatsu extract but much lower response to neem extract.
The response to akamatsu plus neem was mostly the same as that to neem alone, suggesting the neem extracts inhibited the responses
to akamatsu extracts. In the present article, we discuss the correlations between the feeding behaviors and the responses
at their taste cells to these different extracts. 相似文献
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A quantitative HPLC analysis of the major triterpenoids present in an aqueous extract of powdered neem kernels prepared in the traditional manner was undertaken. The study shows that water extracts contain all the principal triterpenoids in neem kernel though the quantities extracted are much less than in the subsequent extraction with methanol. 相似文献
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Efficiency of neem and groundnut oils in protecting leguminous tree seeds against seed beetles in the Sahel 总被引：1，自引：0，他引：1
The objective of our study was to test the comparative efficiency of neem (Azadirachta indica) kernel oil, groundnut oil and a synthetic insecticide, K-Othrine®, in protecting stocks of leguminous tree seeds against seed beetles under Sahelian conditions. The following insect/seed combinations were used as models: Caryedon acaciae/Acacia nilotica, C. longispinosus/A. raddiana and C. serratus/Tamarindus indica. Neem oil, when used at concentrations of 5 to 20 ml per kg of seeds, had pronounced adulticidal and ovicidal effects which were maintained for five months. No significant fall in seed viability was observed except in the case of C. acaciae/A. nilotica. Groundnut oil, when used at concentrations of 5 to 20 ml per kg of seeds, had pronounced adulticidal and ovicidal effects which were relatively short-lived. A significant fall in seed viability was observed over five months. K-Othrine®, when used at concentrations ranging from 25 to 100 mg per kg, had high adulticidal effects which were maintained for five months. However, K-Othrine® was found to have no ovicide properties. No significant fall in seed viability was observed. This study concluded that it is possible to use neem oil, a product that can be obtained locally at low cost, to efficiently protect tree seed stocks in the Sahel.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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采用物理破碎油茶籽细胞和酶降解相结合的方法提取油茶籽油,对油茶籽原材料的预处理时间和温度,酶解方法进行了研究,探索蛋白酶在水性条件下酶解油茶籽的提油工艺及其影响因素,结果表明:油茶籽原材料预处理的适宜加热温度为90℃、加热时间为2 h,适宜的酶解温度为38℃、pH值为8、水解酶用量为0.25%(占油料的质量比重)、酶解时间为4 h。 相似文献
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Insecticidal seed treatment is an alternative method to spray and granular applications. It can protect the crop right from
germination to reproductive stage. Recurrent use of chemical insecticides destabilizes the ecosystem and enhances the development
of resistance in pest population. Use of biopesticides like neem oil (NO) is a promising one in this situation. Two field
experiments were conducted to test the efficacy of NO as a seed dresser (20 ml kg−1) and the effect was compared with systemic chemical insecticides imidacloprid (7 g kg−1) and carbosulfan (7 g kg−1) and Pseudomonas fluorescens (10 g kg−1). Field studies revealed that the neem oil 60EC (C) (NO 60EC (C)) recorded minimum population of sucking pests Leafhopper—Amrasca biguttula biguttula Ishida and Aphids—Aphis gossypii Glover (Homoptera: Cicadellidae and Aphididae), i.e., below the ETL (2 number per leaf) up to 45 days after sowing and provided
better yield compared to control. Although the systemic chemical insecticide imidacloprid performed better by recording 11,280
and 11,580 kg ha−1 of marketable fruit yield, NO 60EC (C) also recorded about twofold increase in marketable fruit yield 11,000 and 10,620 kg ha−1, respectively, in 2001 and 2002 experiments. Results of this study suggest that NO could be used as a potential seed dresser
for managing sucking pests in okra. 相似文献