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1.
The machanisms by which the larvae of the larch sawfly,Pristiphora erichsonii (Hartig), are prevented from feeding on the single needles of the new shoot of tamarack,Larix laricina (DuRoi) K. Koch, were studied. As a result of extensive purification attempts, five deterrent chemicals were isolated and identified. They are: abietic, dehydroabietic, 12-methoxyabietic, sandaracopimaric, and isopimaric acid. These chemicals, particularly the first two, are abundant in mid-July to August in the single needles and, apparently, provide the basis for the deterrency against the larval feeding.Research supported in part by the School of Natural Resources, College of Agricultural and Life Sciences, University of Wisconsin-Madison, under a grant from the McIntire Stennis Program. Project No. 2243.  相似文献   

2.
松香树脂酸的单离与应用   总被引:14,自引:0,他引:14  
分别综述了枞酸、左旋海松酸、脱氢枞酸、新枞酸等松香树脂酸在医药、农药、表面活性剂制备以及在其他精细化学品合成中的应用,指出纯粹的松香树脂酸作为绿色化学合成的原料有广阔的工业应用前景。介绍了松香树脂酸单离的胺盐结晶方法,提出对松香树脂酸单离的研究重点是加快胺化反应速度、强化结晶传递过程、采用反应与分离耦舍的方法,以提高松香树脂酸的提取率。  相似文献   

3.
Summary About half of the rosin acids in whole and distilled tall oil consist of abietic and neoabietic acids, as distinguished from hydroabietic acids, dehydroabietic acid, and the pimaric acids. In this respect the tall oil rosin acids are similar to those from gum or wood rosin. This was established by spectrophotometric analysis of the rosin acids from whole tall oil, double distilled tall oil, rosin acids crystallized from tall oil, and rosin acids separated from tall oil by fractional distillation. The rosin acids crystallized from tall oil contained the highest percentage of abietic acid, but the sum of abietic and neoabietic acids was only slightly higher. The rosin acids from acid refined tall oil contained appreciably less abietic and neoabietic acid than the others. Before spectrophotometric analysis the rosin acids were isolated from the tall oils in about 95% yield by cyclohexylamine precipitation.  相似文献   

4.
The qualitative and quantitative composition of the acid fraction of wood extractives from three SpanishPinus pinaster Ait. subspecies (Atlantic, mountain Mediterranean and plain Mediterranean) were studied. Seven samples of each subspecies were prepared according to Technical Association of Pulp and Paper Standards, extracted with petroleum ether (b.p. 40–60°C) in a Soxhlet apparatus and saponified with ethanolic 0.4N potassium hydroxide. The acid fraction was methylated with diazomethane and studied by combined gas chromatography/mass spectrometry. The major constituents found were palmitic, oleic and linoleic among the fatty acids and pimaric, sandaracopimaric, levopimaric, isopimaric, abietic and dehydroabietic among the resin acids. Neoabietic and palustric acids were not found. Variations in the quantitative composition of the acid fraction enable us to distinguish the three subspecies. Main quantitative differences are found between the Atlantic subspecies and the two Mediterranean subspecies.  相似文献   

5.
The behavior of resin acids during tall oil distillation was studied by analyzing samples from six industrial-scale processes. The same artifact resin acids were formed in all processes. However, the proportion of artifact resin acids in tall oil rosins varied from 8.3 to 18.3% of the resin acids. The lowest values were found for two processes utilizing thin-film evaporators. The yield of resin acids in the tall oil rosin fraction varied from 62 to 80% of the resin acids in the crude tall oil feeds. Dehydroabietic acid was formed in all processes, the amount in rosin being 14-44% more than in the crude tall oil feed. Of the abietic acid, only 45-82% was recovered in the tall oil rosin fraction. The distribution of various resin acids and their reaction products during distillation was determined. Major resin acid impurities in tall oil fatty acids were 8,15-pimaradien-18-oic acid and 8,15-isoprimaradien-18-oic acid, both formed chiefly during distillation, and two secodehydroabietic acid isomers common in crude tall oils. The reactions of resin acids leading to new isomers or non-acidic products are discussed. Some results of this work were presented at the 173rd American Chemical Society Meeting, New Orleans, March 1977.  相似文献   

6.
Cytochrome P450s are very versatile enzymes with great potential for biotechnological applications because of their ability to oxidize unactivated C? H bonds. CYP105A1 from Streptomyces griseolus was first described as a herbicide‐inducible sulfonylurea hydroxylase, but it is also able to convert other substrates such as vitamin D3. To extend the substrate pool of this interesting enzyme further, we screened a small diterpenoid compound library and were able to show the conversion of several resin acids. Binding of abietic acid, dehydroabietic acid, and isopimaric acid to the active site was assayed, and Vmax and Km values were calculated. The products were analyzed by NMR spectroscopy and identified as 15‐hydroxyabietic acid, 15‐hydroxydehydroabietic acid, and 15,16‐epoxyisopimaric acid. As the observed products are difficult to obtain by chemical synthesis, CYP105A1 has proved to be a promising candidate for biotechnological applications that combine bioconversion and chemical synthesis to obtain functionalized resin acids.  相似文献   

7.
The resin acid composition of Finnish tall oil rosin was investigated by gas chromatography and mass spectrometry employing open tubular capillary columns. On a column coated with 1,4-butanediol succinate, 16 resin acids found in tall oil rosin samples were well resolved, and mass spectra could be recorded. All resin acids were confirmed to be of the pimaric and abietic types by gas chromatographymass spectrometry. Eight of the acids were not detected in the corresponding crude tall oils and evidently had been formed during the technical distillation process. The presence of 8,15-pimaradien-18-oic and 8,15-isopimaradien-18-oic acids in the rosin, but not in the crude tall oil, indicates that the pimaric type acids also undergo extensive isomerization during tall oil distillation. Additionally, three dihydroabietic acids and two acids with identical mass spectra, tentatively stereoisomers of 7,9(11)-abietadien-18-oic acid, were formed during the distillation process.  相似文献   

8.
通过松香与丙烯酸的Diels-Alder加成反应制备了丙烯海松酸,考察了原料摩尔比对反应的影响。实验结果表明,随着丙烯酸用量的增加,产物的酸值和软化点逐步升高至不变;紫外光谱研究发现,随着丙烯酸用量的增长,枞酸型树脂酸相对含量下降,而海松酸型树脂酸的含量未见显著变化;气相色谱-质谱联用分析显示,在松香树脂酸与丙烯酸的加成反应中,树脂酸中的海松酸、异海松酸、脱氢枞酸等不参与反应,而长叶松酸、枞酸和新枞酸异构化为左旋海松酸,与丙烯酸发生加成反应;即使丙烯酸过量,长叶松酸和枞酸转化率最高也只可以达到91%和86%;研究还发现,加成产物丙烯海松酸有二种构造异构体,分别占丙烯海松酸量的20%和80%。  相似文献   

9.
气相色谱用马尾松松香标准样品的定值   总被引:1,自引:0,他引:1  
系统地介绍了气相色谱用马尾松松香标准样品的定值方法。采用单一方法通过6家实验室联合定值,得到标准样品中7种树脂酸的GC含量(%)的特性值和扩展不确定度:海松酸8.2683±0.3203;山达海松酸:1.7433±0.3199;异海松酸:0.7652±0.3118;长叶松酸:30.8201±1.3668;去氢枞酸:3.2731±0.8693;枞酸:34.9275±1.2664;新枞酸:18.7469±1.8494。  相似文献   

10.
歧化松香的气相色谱和紫外分光光度分析方法比较   总被引:2,自引:0,他引:2  
采用1102型气相色谱仪和紫外分光光度计分别对自制歧化松香产品的组成、含量分析。气相色谱法能够准确、全面地对歧化松香产品进行松香树脂酸含量的分析测定。按照ZB B 72002-1984《歧化松香》,使用两台不同型号的紫外分光光度计对产品中的枞酸和脱氢枞酸含量进行分析测定,选择狭缝宽度为0.1 nm,紫外分光光度法对枞酸含量在0.05%~4.88%、脱氢枞酸含量在41.1%~50.9%之间的歧化松香产品分析较准确。  相似文献   

11.
Diterpene resin acids (DRAs) are important components of oleoresin and greatly contribute to the defense strategies of conifers against herbivorous insects. In the present study, we determined that DRAs function as insect juvenile hormone (JH) antagonists that interfere with the juvenile hormone-mediated binding of the JH receptor Methoprene-tolerant (Met) and steroid receptor coactivator (SRC). Using a yeast two-hybrid system transformed with Met and SRC from the Indian meal moth Plodia interpunctella, we tested the interfering activity of 3704 plant extracts against JH III-mediated Met-SRC binding. Plant extracts from conifers, especially members of the Pinaceae, exhibited strong interfering activity, and four active interfering DRAs (7α-dehydroabietic acid, 7-oxodehydroabietic acid, dehydroabietic acid, and sandaracopimaric acid) were isolated from roots of the Japanese pine Pinus densiflora. The four isolated DRAs, along with abietic acid, disrupted the juvenile hormone-mediated binding of P. interpunctella Met and SRC, although only 7-oxodehydroabietic acid disrupted larval development. These results demonstrate that DRAs may play a defensive role against herbivorous insects via insect endocrine-disrupting activity.  相似文献   

12.
Tall oil is one of the side products from the kraft pulping process of lignocellulosic material. The most abundant acid found in this crude viscous material is abietic acid. Strangely, in the past, the utilization of tall oil has been limited to incineration for cogeneration of power. In this study, tall oil rosin acids (TORAs) were used in two different applications. First, it was used to enhance the hydrophobicity and thermal properties of hemp fibers. Second, TORAs were used to supplement epoxy for the production of a polymeric material. The reaction conditions from a model study were mimicked using a crude tall oil rosin acid mixture to enhance hemp fibers. Treated hemp fibers were characterized with increased surface hydrophobicity and improved thermal properties. Also, IR and X‐ray photoelectron spectroscopy confirmed successful chemical modification and grafting of carbon rich moieties onto the surface of the fibers, respectively. Furthermore, TORAs were used to supplement epoxy resin and produced plastics with comparable properties to pure epoxy based plastics. Specifically, 25% (w/w) replacement exhibited little difference in thermal stability and curing when compared to virgin epoxy plastics. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44327.  相似文献   

13.
枞酸是从天然可再生资源松香中分离得到的产品,由于松香是包含13种树脂酸的混合物,而且这些树脂酸多为同分异构体,导致其物理性质相近,使得枞酸单离非常困难,很多情况下是以混合物的形式应用于各种工业领域中,用途受到了一定的限制。本文介绍了枞酸的几种主要单离方法,分析了各种单离方法的优缺点,认为有机胺盐结晶法是枞酸工业生产最可行的方法。此外,本文还介绍了枞酸在合成生物活性物质方面的应用以及在医药、农药、精细化学品等领域的应用研究进展,最后,指出将松香所含的多种树脂酸逐一分离提纯,并以之作为原料,合成一系列具有生物活性的物质和药物,是未来枞酸综合开发利用的重点。  相似文献   

14.
Compositions of six grades of tall oil pitch (TOP), four of finnish and two of U.S. origin were investigated. The pitch samples contained 34.6–51.6% free acids, 23.2–37.8% esterified acids, and 25.3–34.4% unsaponifiable neutral compounds. Each of the above fractions was analyzed by high resolution gas chromatography-mass spectrometry. Approximately 60% of the weight fraction in TOP consisted of high molecular components of which about half were acidic compounds. The low molecular free acids were mainly dehydroabietic, abietic, and other resin acids. The esterified acids consisted chiefly of oleic and linoleic acids. Unsaponifiable fractions were composed of diterpene alcohols, fatty alcohols, sterols, and dehydrated sterols. The alcohol components were almost completely esterified.  相似文献   

15.
Diterpene resin acids significantly affect consumption rates, feeding efficiencies, and growth rates of the larch sawfly,Pristiphora erichsonii (Hartig) when topically applied to their natural food, tamarackLarix laricina (DuRoi) K. Koch. Abietic acid, neoabietic acid, dehydroabietic acid, and isopimaric acid significantly reduced consumption rates, feeding efficiencies, and growth rates. Sandaracopimaric acid reduced growth and efficiency but did not influence consumption rate. Two-way analysis of variance indicates a significant interaction between chemical and concentration for growth rate, feeding efficiency, and consumption rate. This interaction indicates that increasing chemical concentrations do not influence the larch sawfly in a uniform manner, supporting the concept of concentration-dependent biological activity of allelochemics.Research supported by School of Natural Resources College of Agriculture and Life Sciences, University of Wisconsin-Madison and School of Forestry, Northern Arizona Univeristy under grants from the McIntire-Stennis Program.  相似文献   

16.
Diterpene resin acids are major constituents of conifer oleoresin and play important roles in tree defense against insects and microbial pathogens. The tricyclic C-20 carboxylic acids are generally classified into two groups, the abietanes and the pimaranes. The abietanes have conjugated double bonds and exhibit characteristic UV spectra. Here, we report the analysis of abietanes by reversed-phase high-performance liquid chromatography using multiwavelength detection to optimize quantification of underivatized abietic, neoabietic, palustric, levopimaric, and dehydroabietic acids. The utility of the method is demonstrated with methanol extracts of white spruce (Picea glauca) phloem, and representative concentrations are reported.  相似文献   

17.
Two monophagous sawflies,Neodiprion dubiosus andN. rugifrons, actively avoid feeding on the current season's needles of jack pine,Pinus banksiana, while the polyphagousN. lecontei feeds indiscriminately on foliage of all age classes. Bioassay studies with needle extracts indicate thatN. dubiosus andN. rugifrons larval feeding preference is governed by a group of tricyclic diterpene resin acids. Resin acids commonly occur in needles of all ages; however, levopimaric, palustric, dehydroabietic, and neoabietic acids were at higher concentrations in the new needles.N. dubiosus was significantly deterred from feeding on 1-year-old foliage when treated with the pure resin acids, palustric and levopimaric, at 0.5 and 1.0 mg/ml MeOH.N. rugifrons larvae were deterred from feeding by pure dehydroabietic, neoabietic, and palustric acids at 1.0 mg/ml MeOH.  相似文献   

18.
采用GC和GC-MS-DS联用技术在线跟踪分析了Pd/C催化剂上松脂直接催化歧化反应过程主要化学组成随时间的变化关系,并探讨了松脂催化歧化反应机理. 考察了不同反应条件对歧化反应产物的影响,结果表明,松脂可直接催化歧化反应同时获得歧化松香和对伞花烃,在250℃、催化剂用量0.05%(占松脂的质量)的反应条件下,反应90 min时脱氢枞酸与枞酸含量分别占酸性物含量的79.15%和0,对伞花烃含量占中性油含量的62.52%;松脂中酸性物的反应速度大于中性油,在二者同时进行的氢转移反应中,树脂酸脱氢与萜烯脱氢反应均是主反应;以松脂为原料的歧化反应速度大于松香为原料的歧化反应速度,直接以松脂为原料进行一步催化歧化反应,萜烯不仅作为溶剂降低了反应体系的粘度,促进了液固传质并促进了枞酸芳构化反应的进行,同时树脂酸提供了有机酸的质子源,使松节油中的双环单萜异构并芳构化形成对伞花烃. 本研究为该反应动力学研究和反应条件优化提供了理论依据.  相似文献   

19.
Pinolenic acid (5Z,9Z,12Z-octadecatrienoic acid, 1a), one of the most abundant trienoic fatty acids in nature, is very difficult to obtain in quantity in a pure state from the highly complex mixture of unsaturated tall oil fatty acids. For this reason its chemistry has been little studied when compared to linolenic or linoleic acids. A simple synthesis of esters of 1a and of 12Z,15Z-octadecadienoic acid 3 using the one pot double Wittig procedure is described here. The products of double Wittig reactions were purified by argentation chromatography, and their structural purity was established by 1H-, 13C-NMR and 2D-NMR spectroscopies.
Tapio HaseEmail:
  相似文献   

20.
建立了高效液相色谱-紫外可见检测器法(HPLC-VWD)测定妥尔油脂肪酸中松香酸含量。通过实验确定较优分析方法,结果表明,此方法在5~500 mg/L范围内具有良好的线性(r=0.9999),平均加标回收率为99.3%,准度度高,重复性实验相对标准偏差(RSD)均小于1.0%,精密度良好。此方法可用于精确测定妥尔油脂肪酸中松香酸含量。  相似文献   

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