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1.
Piperidine Alkaloids in Nitrogen Fertilized Pinus ponderosa   总被引:2,自引:0,他引:2  
We fertilized individual, pole-size ponderosa pine trees at two low-quality sites and pine saplings at a relatively high-quality site, with ammonium nitrate. Six to 12 months later, we measured total %N and 2,6-disubstituted piperidine alkaloids in the foliage. The N additions raised foliar %N above deficiency levels (i.e., from 1.0–1.1% to 1.4–1.6%) at the low-quality sites, but did not elevate foliar %N in saplings at the higher quality site, where it was already (1.9%) well above critical levels. In control trees with foliar N below a threshold of 1.1%, we detected no more than trace levels of alkaloids, indicating that alkaloid production is highly constrained by N deficiency. The N additions increased mean concentrations of the predominant alkaloid, pinidine, at all three sites. Mean total alkaloid concentrations for fertilized trees at the two low-quality sites were 12 and 155 g/g dry wt higher than controls (relative increases of 12× and 4.5×, respectively). For saplings at the high-quality site, the mean total increased by 584 g/g dry wt (1.6×) with the N additions. Allocation of foliar N to alkaloids was highest in fertilized saplings (0.81%) compared to control saplings (0.53%). These findings demonstrate that foliar alkaloid concentrations can be increased by nitrogen fertilization of forest trees growing on both low- and high-quality sites. Fertilizing for the purpose of inhibiting potential herbivores may be more successful at higher quality sites where alkaloid levels are enhanced relative to food quality (foliar %N).  相似文献   

2.
Seasonal changes in the production of primary nutrients (soluble carbohydrates) and secondary metabolites (terpenes, monomeric phenolics, and tannins) in the current needle tissue of Douglas fir were investigated. All four classes of compounds showed significant seasonal changes in concentration during foliage development. Most terpenes increased significantly in concentration from June 11 to August 3, and then showed declining concentrations to September 20. The most dramatic and significant seasonal increases occurred in-pinene, camphene, and bornyl acetate concentrations. The monomeric phenolics chlorogenic acid, taxifolin glucoside, quercetin galactoside, and those unknown phenolics showed an overall trend of declining in concentration from June 11 through September 20. However, considerable variation between sampling dates in the concentration of these phenolics was noted. Tannin concentration decreased significantly from June 11 to July 9, and then increased in concentration to the September 20 sampling date. Fructose, galactose, glucose, and sucrose tended to decrease from June 11 to September 20. However, significant variation between sampling dates was evident in these compounds as well. Galactose was the major compound in the soluble carbohydrate fraction, amounting to almost 80% of the total concentration throughout the growing season. These data suggest that if phenolics and tannins function as defenses, they would only affect second- and possibly third-instar budworm larvae during the time that these instars mine the buds. Camphene,-pinene, and bornyl acetate increased in concentration throughout the growing season and may be effective deterrents to the budworm. Both bornyl acetate and camphene have been shown in field and laboratory studies to increase larval mortality and adversely affect budworm larval growth. Carbohydrates generally act as nutrients that enhance herbivore growth. However, in a previous study, galactose was found to cause reduced budworm larval growth and increased larval mortality.  相似文献   

3.
The current year's growth of Douglas fir contains galactose, unusual in that this carbohydrate makes up 78.7% of the total carbohydrate fraction. An agar diet study was undertaken to determine the effects of galactose, other carbohydrates, and terpenes on western spruce budworm larval mortality, growth rate, and adult biomas production. All concentrations of the carbohydrates and terpenes tested, as well as other mineral elements not tested, were typical of the current year's foliage of Douglas fir. In experiment I, the diet containing 5.61% total carbohydrate did not significantly affect larval mortality when compared to the control diet. However, diets containing 9.45% and 15% total carbohydrate concentrations significantly increased larval mortality 64% and 96.1%, respectively, when compared to the control. Also in experiment I, terpenes alone (78.9% morality) and terpenes in combination with 9.45% and 15% total carbohydrates significantly increased larval mortality (97.2% and 100%, respectively) when compared to mortality on the control diet (44%). To determine which carbohydrate was causing the adverse effect, 6% glucose, 6% fructose, and 6% galactose were placed individually and in combination with terpenes in diets in experiment II. The 6% galactose diet significantly increased larval mortality and reduced growth rate when compared to the control, glucose, and fructose diets. Glucose resulted in 16% less larval mortality, significantly enhanced female larval growth rate and pupal weight, but did not affect male larval growth rate and pupal weight, when compared to the control. Fructose resulted in a significant decrease in larval mortality and a general trend of enhanced female and male larval growth rate and pupal weight. Larval mortality on terpenes alone was not significantly different from the control, but terpenes with 6% galactose increased larval mortality and decreased female and male growth rate and pupal weight significantly when compared to glucose-terpene and fructose-terpene diets. No significant interactions were found between carbohydrates and terpenes in either experiment.  相似文献   

4.
Twigs from five ponderosa pine trees (Pinus ponderosa) used by Abert squirrels (Sciurus aberti) as feed trees and five nonfeed trees were collected every 45 days and their monoterpenoid and nutrient content determined. Thet tests (unpaired observations) detected no significant difference in the level of monoterpenoids in the outer bark of feed (0.77%) and nonfeed (0.75%) trees. The same was true for inner bark of feed (0.10%) and nonfeed (0.16%) trees. Monoterpenoid levels in outer bark (0.75%) were significantly higher than inner bark (0.13%). The inner bark is what is eaten by Abert squirrels. Protein and other nutrients did not differ significantly between feed and nonfeed trees. However, both outer and inner bark were easier to remove from the woody portion of the feed tree twigs than those twigs collected from nonfeed trees. Therefore, due to the lack of differences in monoterpenoid and nutrient content between feed and nonfeed trees, we attributed the use of certain trees for use as feed trees to the ease of peeling and separating outer from inner bark.Located at Shrub Sciences Laboratory, 735 North 500 East, Provo,Utah 84601.  相似文献   

5.
MaleIps paraconfusus Lanier bored and fed in cellulose powder substrates treated with solvent extracts of ponderosa pine phloem in preference to cellulose powder alone. Stimuli that elicit boring and feeding behavior occurred in the water extracts and the combined solvent extracts. No significant boring or feeding occurred in the methanol extract. There was a preference for, but no significant feeding in, the water partition of the ether extract. Feeding, but no preferential boring, occurred in the ether extracts.Coleoptera: Scolytidae.Research supported by the Rockefeller Foundation, an NIH Training Grant, USDA/SEA Regional Research Project W-110, and the USDA Forest Service.From a thesis submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy, by J.S.E., 1979, University of California, Berkeley, California.  相似文献   

6.
鲁珍 《广州化工》2012,40(18):18-19,96
水葫芦的资源化利用,可以获得可观的能源。当前,水葫芦大量增长,对水葫芦资源化利用技术主要集中在厌氧发酵产沼气和制氢。这些技术取得了一些进展,但实际工程化应用较少。本文综述了水葫芦厌氧发酵技术研究进展并指明以后研究重点是如何提高这些技术的可行性与效率并达到工程化应用,减少水葫芦的危害。  相似文献   

7.
Logs from the base of Douglas fir (Pseudotsuga menziesii) trees cut in October 1993 were randomly assigned to one of three treatment groups: (1) wet logs—cut from the fallen tree and left exposed to rain, (2) dry logs—cut from the fallen tree, placed on blocks, and protected from rain under a plastic tent, and (3) crown logs—left attached to the fallen tree with its branches intact and exposed to rain. The following May, ethanol concentrations were highest in the phloem and sapwood of wet logs (0.24 and 0.35 mol/g fresh wt, respectively). Ethanol concentrations in tissues from dry and crown logs were similar to each other (ranging from 0.002 to 0.03 mol/g fresh wt), but were significantly lower than in wet logs. It appears that rain absorbed by the outer bark of wet logs creates a barrier to gas exchange between living tissues and the atmosphere, which facilitates the development of hypoxic conditions necessary for ethanol synthesis and accumulation. Branches on crown logs exposed to rain help maintain low ethanol concentrations in the log tissues; we discuss several potential mechanisms to explain this response. By early September, the densities of Gnathothrichus spp. gallery entrance holes were high on wet logs (21.5/m2) and low on dry (2.5/m2) and crown logs (5.8/m2), indicating their preference for logs with higher ethanol concentrations. Protecting logs from rain will significantly reduce ethanol concentrations and the density of ambrosia beetle galleries. Leaving branches attached to logs will produce similar results, but its effectiveness may vary depending on the environmental conditions. Host selection by secondary scolytid beetles that use ethanol as a kairomone can be manipulated and possibly managed by controlling the production of ethanol in the host resource.  相似文献   

8.
以平煤十二矿的焦煤、煤矸石、矿井水为研究对象,在添加接种物的条件下,以硫酸根、硝酸盐氮、氨氮、氟化物、硫离子、pH值和重金属为研究指标,对发酵液进行测定,结果表明:硫酸盐和产甲烷菌在一定条件下可以共存;整个系统的pH值呈弱碱性;氨氮严重超出了地下水的标准;各种重金属随着浸泡时间的延长有不同变化,但均未超出地下水Ⅲ类标准;浸泡时间的长短和接种物的加入使各指标之间有明显差异,是影响地下水的重要因素。  相似文献   

9.
介绍了以煤为原料生产燃料乙醇的4条工艺技术路线:合成气化学催化法、合成气厌氧发酵法、醋酸直接加氢法和醋酸酯化加氢法的反应机理、技术特点及最新进展,并且对各条路线的优势和劣势进行了对比,认为煤制乙醇将成为我国能源化工产业的重要组成部分。  相似文献   

10.
The isolation and purification of polysaccharides extracted from the cones, bark, and needles of Pinus koraiensis (Korean pine) were studied. The amounts of polysaccharides were 42.7%, 53.4%, and 48.4% for cones, bark, and needles, respectively. All these samples contained uronic acid. The total protein and polyphenols were <4.5% for all three samples. With acid hydrolysis, seven polysaccharides were found in different molar ratios in each sample: D-ribose, L-rhamnose, L-arabinose, D-xylose, D-mannose, D-glucose, and D-galactose. The relationships between in vitro antioxidant properties (AOP) of polysaccharides extracted from different parts of the P. koraiensis tree are correlated with physicochemical properties (the amount of neutral sugars, uronic acid, and proteins). Moreover, the pinecone polysaccharides (PKCP) confirmed previously observed beneficial antioxidant capacity with an EC50 of OH radical, ABTS radical scavenging, and reducing power of 6.54, 5.06, and 9.15 mg/mL, respectively. PKCP had the best antioxidant activity among the three samples.  相似文献   

11.
It has been suggested that cytoplasmic petite mutants of Saccharomyces yeasts might be useful in commercial ethanol production since they are incapable of respiration. The authors have compared the rate and extent of ethanol production in a grande strain of S. uvarum and in a cytoplasmic petite mutant derived from it. Increasing the concentration of O2 in the input gas feed to a continuous culture of the grande beyond 0.17% increased the rate of biomass production at the expense of that of ethanol. In contrast, the rates of production of both biomass and ethanol by a similar culture of the petite increased with increasing O2 up to a level of 0.6% of the input flow. Above that level no further increase was recorded. At no O2 level did the yield or productivity of ethanol by the petite exceed the maximum obtainable with the grande. Batch culture studies demonstrated that the petite was more sensitive to the growth inhibitory effects of ethanol than was its grande parent. This may explain the poorer performance of the mutant strain.  相似文献   

12.
November-felled Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) logs with and without branches were left lying on the forest floor through August. In May, as the logs were being colonized by ambrosia beetles,Trypodendron lineatum (Oliv.) andGnathotrichus retusus (LeConte), the ethanol, acetaldehyde, and water concentrations in the delimbed logs were significantly higher than in the branched logs. Since both log types received the same rainfall, lower water contents in branched logs was probably the result of absorbed water being transported through the branches via capillary movement and evaporation. Lower tissue water levels could have prevented the establishment and maintenance of anaerobic conditions, thus limiting the synthesis of acetaldehyde and ethanol in the branched logs. By late August, the beetle densities in delimbed logs were 9–16 times greater than in the branched logs. Log ethanol concentrations could be a key chemical factor affecting the ambrosia beetle attack densities. Acetaldehyde concentrations in the logs also may have affected the attack densities.  相似文献   

13.
硅橡胶膜生物反应器中乙醇发酵与渗透汽化的耦合   总被引:3,自引:0,他引:3  
用硅橡胶膜生物反应器(SMBR)实验研究连续发酵-渗透汽化的耦合性能。发酵微生物采用酿酒干酵母,所用碳源为工业级葡萄糖。发酵过程由于产物抑制作用,在乙醇质量浓度达到73 g/L时趋于停滞,而耦合渗透汽化膜后,发酵罐内的乙醇质量浓度降低并维持在40 g/L,使发酵可以连续稳定地进行。在SMBR运行达到稳态后,乙醇的体积产率为4.02 g/(L.h)。发酵液中乙醇质量浓度维持在20~63 g/L,聚二甲基硅氧烷(PDMS)膜的总渗透通量为1 220~800 g/(m2.h),分离因子为5~9.2。与传统发酵和分离相同进料质量分数的乙醇溶液相比,乙醇发酵和渗透汽化在硅橡胶膜生物反应器中能相互耦合并得到强化。与较小规模耦合系统(发酵体积1 L和2 L)比较,性能稳定良好。  相似文献   

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15.
Anaerobic biodegradation tests of poly(lactic acid) (PLA) powder were done at the thermophilic (55 °C) and mesophilic temperature (35 °C) under aquatic conditions [total solid concentrations of the used sludge were 2.07% (at 55 °C) and 2.24% (at 35 °C)] using a newly developed evaluation system. With this system, the evolved biogas is collected in a gas sampling bag at atmospheric pressure. This method is more convenient than using a pressure transducer or inverted graduated cylinder submerged in water. PLA was degraded about 60% in 30 days, about 80% in 40 days and about 90% in 60 days at 55 °C. On the other hand, the PLA degradation started in 55 days at 35 °C and degradation rate was much slower than at 55 °C.  相似文献   

16.
赵倩倩  杜广庆  陈丽杰  薛闯  白凤武 《化工进展》2016,35(10):3295-3300
目前关于有氧或微氧的乙醇发酵的尾气检测系统已经建立,但是对于丙酮丁醇梭菌等严格厌氧菌发酵尾气的在线监测鲜见文献报道。因此,本研究以丙酮丁醇梭菌生产丁醇的严格厌氧发酵体系为研究对象,研究了传统有氧或微氧尾气检测方法在丙酮丁醇梭菌厌氧发酵体系中的检测结果,设计并建立了适合厌氧菌发酵的尾气在线监测系统,对丙酮丁醇梭菌的发酵过程实时监测。在建立有效的厌氧发酵尾气分析系统的条件下,比较了丙酮丁醇梭菌在游离细胞条件下和高细胞密度条件下的发酵性能。相比较于游离发酵,高细胞密度发酵的发酵周期明显缩短,丁醇生产强度显著提高。丁醇最高产量为15.4g/L,生产强度0.64g/(L·h),分别比对照组提高了12.4%和106%,CO2和H2最高产气速率分别提高60%和9%,产气量分别提高了20.7%和41.3%。尾气分析系统采集的气体数据为丙酮丁醇梭菌的代谢分析提供了重要依据。  相似文献   

17.
In southern Germany slow-growing pine forests occur on podzolic soils. They may be naturally poor in nutrients (Ca, Mg, P and N) and/or degraded by human interference (causing mainly N-losses).Comprehensive amelioration experiments initiated between 1960 and 1964 were evaluated after 17–20 years. Repeated fertilization with N alone induced P and Mg deficiency on soils low in these elements. Therefore NPMg(K) — fertilization is now recommended in combination with moderate liming. The latter procedure is aimed towards stimulating organic floor turnover and counteracting possible adverse effects of acid deposition. Repeated N dressings as nitrochalk proved to be preferable to N-cyanamide and to lupin undergrowth as an N source for improving the N economy of the pine ecosystems, CaPKMg being supplied equally in both cases. The former procedure improved the nutritional status and growth of pines effectively and without delay, and increased soil fertility without causing major losses of humus and nitrogen. Underplanting of lupins on the other hand, although enhancing soil biological activity impressively, caused considerable damage to pine roots as well as humus losses, and improved nutrition and volume growth of pines only after a prolonged lag period.  相似文献   

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20.
对氨基苯酚在乙醇-水溶液中溶解度的关联   总被引:1,自引:0,他引:1  
郭文淼  徐大智 《辽宁化工》2006,35(3):140-142
测定了鲜见文献报道的对氨基苯酚(p-Aminophenol,简称PAP)在水、乙醇、质量分数为55%的乙醇和水混合溶液中的溶解度,测定的温度范围是从14~77℃。实验数据用经验公式、Apellblat等人提出的溶解度模型[1]、以及Wilson公式进行了验证。实验结果令人满意。  相似文献   

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