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1.
海芒果叶提取物的抑菌活性初探   总被引:4,自引:0,他引:4  
采用冷浸法和超声波提取法对海芒果叶进行提取。以生长速率法测定了各萃取物对9种病原真菌的抑菌作用。结果表明,海芒果叶的正丁醇萃取相的抑菌活性最好;正丁醇萃取相对番木瓜炭疽菌、柑橘炭疽菌、香蕉枯萎菌的EC50分别是1.3964mg/mL、1.7246mg/mL、1.3256mg/mL,其中提取物对香蕉枯萎菌的毒力最高,值得进一步研究。  相似文献   

2.
阴香叶提取物的抑菌活性初步研究   总被引:7,自引:0,他引:7  
骆焱平  郑服丛  谢江 《现代农药》2005,4(2):31-32,43
用不同溶剂对阴香[Cinnamomum burmanii (Nees) Bl] 叶进行提取,以生长速率法测定了提取物对植物病原真菌的抑菌作用。结果表明:阴香叶的氯仿提取物的抑菌活性最好;氯仿提取物对西瓜枯萎菌、芒果炭疽菌、香蕉枯萎菌和香蕉炭疽菌的EC50分别是0.3193mg/ml、0.1552mg/ml、0.0226mg/ml、0.019 2 mg/ml,其中提取物对香蕉炭疽菌的毒力最高,值得进一步研究。  相似文献   

3.
采用快速溶剂萃取法萃取海南江蓠(Gracilaria hainanensis)挥发油,利用气质联用仪对挥发油化学成分进行分析,并利用质谱图进行计算机检索,共鉴定出海南江蓠挥发油中26种化合物,其中2,5-二正丁基吡唑并[5,1-a]异喹啉、2-(2-苯并噻唑基)-5-甲氧基苯酚、1-(六氢吡咯烷嗪-3-亚基)-3,3-二甲基丁烷-2-酮、苯并吗啉、5-氟-4-咪唑羧酸等5种化合物的相对含量较高,分别占24.5%、10.7%、10.5%、10.3%、9.5%。  相似文献   

4.
九里香精油的抑菌活性及成分分析   总被引:1,自引:0,他引:1  
[目的]九里香具有广泛应用价值,研究了精油的抑菌活性及成分.[方法]超临界CO2萃取九里香精油,以生长速率法测定精油的抑菌活性,利用气相色谱-质谱法进行成分分析.[结果]质量浓度为0.5 g/L的九里香精油对供试病菌有较好的抑制作用,对香蕉炭疽菌和芒果炭疽菌的EC50.值分别为0.2611、0.2677 g/L.鉴定出20种化合物,其中主要成分为n-棕榈酸(28.76%)、1-(1,5-二甲基-4-己烯基)-4-甲苯(22.38%)、N-(1-甲基-3-氧-亚丁基)-4-甲氧基苯胺(20.1 1%).[结论]九里香对炭疽菌有较好的抑菌活性,具有进一步研究的价值.  相似文献   

5.
大型海藻细基江蓠制备活性炭的研究   总被引:1,自引:0,他引:1  
以大型海藻细基江蓠为原料制备活性炭,通过正交实验考察了浸渍比(磷酸与细基江蓠粉的质量比,下同)、漫渍时间、活化温度和活化时间对活性炭制备的影响,同时采用红外光谱对活性炭产品的表面官能团进行了分析。确定最佳工艺条件为:浸渍比1:1、浸渍时间9h、活化温度400℃、活化时间50min,在此条件下,活性炭的碘吸附值为1049.75mg·g-1、亚甲基蓝脱色力为123mI。·g-1、得率为37.7%。红外光谱分析表明,活性炭表面存在多种官能团。  相似文献   

6.
红树植物提取物的杀螨活性试验   总被引:5,自引:0,他引:5  
邓业成  玉艳珍  毕秀莲 《农药》2007,46(8):568-570
采用叶片残毒法测定了16种红树植物甲醇提取物对柑橘红蜘蛛的杀螨活性。结果表明,海芒果、苦槛蓝、苦榔树和黄槿对柑橘红蜘蛛雌成螨的触杀活性高,药液质量浓度为10g/L时,24h的校正死亡率达90%以上;榄李、海漆和水黄皮有中等杀螨活性,校正死亡率为66.90%~74.19%;其余植物的杀螨活性低,校正死亡率在50%以下。海芒果、苦槛蓝、苦榔树、黄槿和榄李对雌成螨的致死中浓度(LC50值)分别为1.8416、2.8757、2.9218、4.9325、6.5728g/L。红树植物提取物对柑橘红蜘蛛卵也有触杀活性,其中苦槛蓝、苦榔树、木榄、海漆、老鼠簕、海芒果、白骨壤和草海桐的杀卵活性高,药液质量浓度为10g/L时,校正死亡率在80%以上。  相似文献   

7.
江蓠漂白液清洗方法对提取琼胶的影响研究   总被引:2,自引:0,他引:2  
针对江蓠琼胶加工过程中漂白液清洗不当造成的质量不稳定问题,探讨了清洗方式与江蓠、提胶率和凝胶强度的因应关系,提出了反冲和喷淋相结合的清洗方法,研究结果表明,采用这一方法,在其他工艺条件相同的情况下,可以显著提高提胶率和产品凝胶强度。  相似文献   

8.
刘平怀  张森  汪春牛  陈德力 《精细化工》2013,(3):281-284,287
为研究琼榄的药用活性成分,更好地开发和利用琼榄资源,对琼榄根、茎、叶的5种不同溶剂提取物分别采用清除DPPH自由基法和滤纸片扩散法进行抗氧化及抗菌活性研究。结果表明,琼榄叶的乙酸乙酯提取物(L-EtOAc)清除DPPH自由基的IC50最小,为154.1 mg/L,是15组提取样品中清除自由基活性最强的部位。琼榄根、茎、叶的15组提取物对5种供试菌均具有不同程度的抑菌活性,且以琼榄叶的乙酸乙酯提取部位对5种供试菌的抑菌作用均较强,特别是对金黄色葡萄球菌、大肠杆菌、铜绿假单胞菌的抑制作用和阳性对照品头孢他啶的抑菌作用接近。因此,琼榄叶部位的抗氧化和抗菌活性最强,且活性物质在乙酸乙酯部位,L-EtOAc为有效提取部位。  相似文献   

9.
江蓠提取琼胶后残渣制备羧甲基纤维素的研究   总被引:1,自引:0,他引:1  
对富含纤维素的江蓠提取琼胶后的残渣进行前处理,再加入20倍质量的8%NaOH溶液,经100℃蒸煮2 h便制得江蓠粗纤维素。纤维素经NaOH(质量比3:1)25℃碱化处理45 min后,加入氯乙酸(质量比2.5:1)于65℃进行羧甲基化反应2 h,得到的羧甲基纤维素(CMC)取代度达0.70,红外图谱与试剂CMC相似度高,热分析结果表明实验所得CMC稳定性良好。  相似文献   

10.
以甲硝唑、对羟基苯甲醛及取代肼为原料,经过3步反应,以较高产率合成得到一类新型的甲硝唑-苯腙类化合物,其结构经~1HNMR、~(13)CNMR和元素分析确证,所得化合物经抗菌活性筛选研究。结果表明,大部分化合物都具有较强的抗菌活性。其中以(E)-4-(2-(4-(2-(2-甲基-5-硝基-1H-咪唑-1-基)乙氧基)苯亚甲基)肼基)苯磺酰胺活性最好,对大肠杆菌、铜绿假单胞菌、金黄色葡萄球菌和枯草芽孢杆菌的最低抑制浓度分别为1.56、0.78、0.39和0.39μg/m L。  相似文献   

11.
龙须菜提取琼胶碱处理工艺条件优化   总被引:5,自引:0,他引:5  
为研究高温稀碱处理条件与龙须菜琼胶理化性质间的关系,利用正交试验研究了碱液浓度、碱处理温度和碱处理时间三因素与龙须菜琼胶理化性质间的定量关系。通过综合出胶率、硫酸基含量和3,6-内醚-半乳糖含量的实验结果,得出三组最佳处理条件,再经验证试验,并最终由琼胶的凝胶强度确定碱处理的最佳工艺条件为:碱液浓度为6%,碱处理温度为80℃,碱处理时间为120min。为提高龙须菜琼胶加工质量、降低成本提供了重要科学依据。  相似文献   

12.
13.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

14.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

15.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

16.
Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.  相似文献   

17.
A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by 1H MAS NMR. For direct comparison purposes, an SiO2 coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N2 absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.  相似文献   

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