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1.
Soil application of cement kiln exhausts (electrostatic precipitator dust) at both lower and higher concentrations did not inhibit growth, nodule formation, and productivity inCajanus cajan, vigna radiata, andVigna mungo. In fact, growth was promoted, possibly because of the dust containing most of the elements, such as N, Ca, Fe, Mg, Mn, K, Zn, P, S, and Cu, which are needed for plant growth and root nodulation. Foliar application of the dust did not affect chlorophylls and carotenoids. The rate of photosynthesis as measured by CO2 uptake and stomatal diffusive resistance of all legumes were not affected. There was a biomagnification of Mg and K in leaves and seeds. Addition of the ESP dust did not affect either the soil or nodule rhizobial population. It is evident that the dust did not act as a phytotoxicant but as an elixir of plant life.  相似文献   

2.
For the first time, the chemical composition of the seed essential oil of Rhododendron tomentosum was determined. Forty-seven compounds were identified, comprising 91.7% of the total oil. Palustrol (38.3%) and ledol (27.0%) were the predominant constituents. Some constituents, such as beta-pinene oxide, iso-menthyl acetate, nerolidyl acetate, cadalene and guaiazulene were characteristic only for the seeds and were identified for the first time in Rh. tomentosum oils. For comparison purposes, the essential oil isolated from the shoots of the same plant were analyzed [GC(FID) in combination with RIs, GC-MS and 13C NMR]. More than a half of the oil was comprised of ledol (36.5%) and palustrol (21.0%). Quantitative analysis of ascaridol, a heat-sensitive compound, was carried out by 13C NMR spectroscopy. Indeed, ascaridol undergoes partial thermal isomerization to iso-ascaridol during GC analyses.  相似文献   

3.
Functional properties of native and modified (through induced autolysis) pea (Pisum sativum L.) and broad bean (Vicia faba L.) protein derivatives are studied. In specific, protein solubility and behavior at the air–water interface through surface pressure measurements are investigated. Furthermore the ability of the protein products to act as emulsifying agents and to stabilize emulsions is studied through oil droplet size distribution measurements and by the protein adsorbed at the oil–water interface. The data reveal that the ability of the proteins to act as surfactants and build up a rigid film around the oil droplets, mainly depends on their suitable molecular configuration and structure. Hydrolysis did not promote the functionality of the legume proteins. Broad bean exhibited better functionality than pea, before and after hydrolysis. Some comparisons were also made with lupin (Lupinus albus L.) protein isolate.  相似文献   

4.
It has been established that the change in the composition of the total lipids and the fall in the fatty acid content depend on the initial maize genotype. A decrease in the amount of unsaponifiable substances in the grain of mutants is accompanied by qualitative changes in the composition regardless of the nature of the genotype.Scientific-Research Institute of Biology Dnepropetrovsk State university. Translated from Khimiya Prirodnykh Soedinenii. No. 3. pp. 360–363. May–June, 1988.  相似文献   

5.
The fatty oils of the seeds ofOriganum tyttanthum andMentha asiatica (family Labiatae) have been investigated. The glyceride and fatty-acid compositions of the two oils have been determined. From the oil ofM. asiatica have been isolated the new acid 9-hydroxyoctadeca-12-cis,15-cis-dienoic acid and a mixture of six unsaturated oxo acids.  相似文献   

6.
采用不同极性溶剂提取小花玄参中的化学成分,应用植物化学成分的系统分析法定性研究,并对其总黄酮含量进行测定.结果表明,小花玄参中含有氨基酸、多肽和蛋白质、糖及苷类、有机酸、鞣质、皂苷、甾体或三萜类、黄酮、酚类、挥发油和油脂、强心苷和生物碱等化学成分,未检出蒽醌及香豆素与萜类内酯;小花玄参中总黄酮的含量为5.689%(56.89mg/g).该结果可为小花玄参化学成分的分离纯化、药理研究以及开发利用等提供基础依据.  相似文献   

7.
Data from a recent interlaboratory study of the determination of water (moisture) in animal feed, grain, and forage (plant tissue) by Karl Fischer titration were re-analyzed using Youden plots. The purpose was to show the unique ability these plots possess of separating random and systematic errors visually while providing numerical estimates of the precision and the systematic error of the method. Furthermore, the usefulness of the technique is underscored because AOAC INTERNATIONAL allows the use of matched pairs in collaborative studies to obtain estimates of repeatability and reproducibility.  相似文献   

8.
The developing and under developed countries mostly rely on traditional medicines. This herbal or traditional medicine involves the use of different types of organic extracts or the bioactive chemical constituents. This type of biochemical investigation provides health care at an affordable cost. This survey such as ethnomedicine keenly represents one of the best avenues in searching new economic plants for medicines. Keeping this view in mind, the present study is carried out in Merremia borneensis leaves of University Malaysia Sabah, Sabah, Malaysia. The plant has several beneficial properties, such as antioxidant activity. The dry powder of the leaves of M. borneensis was extracted with hexane, ethyl acetate, chloroform, butanol and aqueous ethanol. The flavonoids content of the extracts was determined by Willet method. The flavonoids content of the extracts as quercetin equivalents was found to be highest in aqueous ethanol (53.28%) followed by chloroform (38.83%), ethyl acetate (24.51%), butanol (12.54%) and hexane extract (3.44%). The results suggest the presence of phytochemical properties in the leaves, which are used in curing the ailments.  相似文献   

9.
Summary The fatty oils of the seeds ofOriganum tyttanthum andMentha asiatica (family Labiatae) have been investigated. The glyceride and fatty-acid compositions of the two oils have been determined. From the oil ofM. asiatica have been isolated the new acid 9-hydroxyoctadeca-12-cis,15-cis-dienoic acid and a mixture of six unsaturated oxo acids.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 149–155, March–April, 1976.  相似文献   

10.
The hydrodistillated seed essential oil of Calocedrus formosana was analyzed to determine its composition and yield. Twenty-seven compounds were identified, the main ones being alpha-pinene (63.8%), totarol (9.9%) and ferruginol (8.9%). Monoterpene hydrocarbons (73.5%) and oxygenated diterpenes (18.8%) were the predominant groups of compounds. The seed essential oil exhibited excellent antioxidant, antimicrobial and anti-wood-decay fungal activities.  相似文献   

11.
12.
A method for determining crude fat in animal feed, cereal grain, and forage (plant tissue) was collaboratively studied. Crude fat was extracted from the animal feed, cereal grain, or forage material with hexanes by the Randall method, also called the Soxtec method or the submersion method. The use of hexanes provides for an alternative to diethyl ether for fat extractions. The proposed submersion method considerably decreases the extraction time required to complete a batch of samples compared to Soxhlet. The increase in throughput is very desirable in the quest for faster turnaround times and the greater efficiency in the use of labor. In addition, this method provides for reclamation of the solvent as a step of the method. The submersion method for fat extraction was previously studied for meat and meat products and was accepted as AOAC Official Method 991.36. Fourteen blind samples were sent to 14 collaborators in the United States, Sweden, Canada, and Germany. The within-laboratory relative standard deviation (repeatability) ranged from 1.23 to 5.80% for crude fat. Among-laboratory (including within) relative standard deviation (reproducibility) ranged from 1.88 to 14.1%. The method is recommended for Official First Action.  相似文献   

13.
通过优化原子荧光光谱仪的原子化高度、负高压、灯电流和载气流量等4个主要工作条件,并对仪器产生干扰的因素环境温度、光源稳定性、试剂进行研究,并用加标回收实验对方法的准确度进行验证,确定了原子荧光光谱法同时测定粮食中砷汞总量时的最优条件和有效的干扰控制方法。结果显示,在最优条件下,As的检出限为0.024 7ng/mL,相对标准偏差(RSD)为0.37%,线性相关系数r=0.999 9;Hg检出限为0.001 5ng/mL,相对标准偏差(RSD)为0.44%,线性相关系数r=0.999 9,仪器检测稳定性好,灵敏度高,各项指标均优于标准规定,且检测结果精密度高、准确性好。  相似文献   

14.
A Karl Fischer method for determining water (dry matter) in animal feed and forages was collaboratively studied. Water was extracted from animal feed or forage material into methanol-formamide (1 + 1) directly in the Karl Fischer titration vessel by high-speed homogenization. The water was titrated at 50 degrees C with one-component Karl Fischer reagent based on imidazole. Ten blind samples were sent to 9 collaborators in the United States, Canada, and Germany. The within-laboratory relative standard deviation (repeatability) ranged from 1.14 to 6.99% for water or from 0.09 to 0.56% for dry matter. Among-laboratory (including within-) relative standard deviation (reproducibility) ranged from 5.35 to 10.73%, or from 0.44 to 0.77% for dry matter. The authors recommend that the method be adopted as Official First Action by AOAC INTERNATIONAL. A comparable alternative extraction procedure using boiling methanol is also recommended for Official First Action.  相似文献   

15.
A method for determining crude fat in animal feed, cereal grain, and forage (plant tissue) was collaboratively studied. Crude fat was extracted from the animal feed, cereal grain, or forage material with diethyl ether by the Randall method, also called the Soxtec method or the submersion method. The proposed submersion method considerably decreases the extraction time required to complete a batch of samples. The increase in throughput is very desirable in the quest for faster turnaround times and the greater efficiency in the use of labor. In addition, this method provides for reclamation of the solvent as a step of the method. The submersion method for fat extraction was previously studied for meat and meat products and was accepted as AOAC Official Method 991.36. Fourteen blind samples were sent to 12 collaborators in the United States, Sweden, Canada, and Germany. The within-laboratory relative standard deviation (repeatability) ranged from 1.09 to 9.26% for crude fat. Among-laboratory (including within) relative standard deviation (reproducibility) ranged from 1.0 to 21.0%. The method is recommended for Official First Action.  相似文献   

16.
Gas-phase hydrogen/deuterium (H/D) exchange was used to probe the conformations, gas-phase acidities, and sites of deprotonation of isomeric flavonoid aglycons and glycosides. The flavonoids in each isomer series were differentiated on the basis of their relative rate constants and total numbers of exchanges. For example, flavonoids that possess neohesperidose-type disaccharides may undergo faster and far more extensive exchange than isomeric rutinoside flavonoids. The structural factors that promote or prevent H/D exchange were identified and correlated with collisionally activated dissociation (CAD) patterns and/or molecular modeling data (both high-level ab initio acidity calculations and conformational analysis with molecular dynamics (MD) simulations), thus providing a framework for the use of H/D exchange reactions in the structural elucidation of new flavonoids.  相似文献   

17.
Honey is rich in phenolic acids and flavonoids, which exhibit a wide range of biological effects and act as natural antioxidants. The analysis of polyphenols has been regarded as a very promising way of studying floral and geographical origins of honeys. This review surveys recent literature on determination of these active compounds in honey. The analytical procedure to determine individual phenolic compounds involves their extraction from the sample matrix, analytical separation and quantification. We pay particular attention to sample pre-treatment and separation techniques (e.g., high-performance liquid chromatography and electrophoresis).  相似文献   

18.
A convenient and efficient procedure for the epoxidation of chromone, isoflavone, and chalcone derivatives using 1-butyl-3-methyl imidazolium tetrafluoroborate [bmim]BF4 as solvent and alkaline hydrogen peroxide as oxidant is described. All reactions proceed in good yields and faster than in conventional solvents. No evidence of formation of compounds derived from the opening of the epoxide ring was attained.  相似文献   

19.
A rapid and economical method is described for the determination of deltamethrin in wheat, rice, peanuts and corn. It is based on simultaneous extraction and clean-up on a column packed with alumina and silica gel using n-hexane-ethyl ether (8:2, v/v), followed by a derivatization step and gas-chromatographic analysis. Recoveries from fortified cereal and peanut samples were determined at four concentration levels and ranged from 73 to 109%. The detection limits were 0.01 to 0.03 mg/ kg. This method simplifies the traditional procedures in terms of sample size, solvent consumption and analysis time. Received: 25 March 1997 / Revised: 3 June 1997 / Accepted: 4 June 1997  相似文献   

20.
A rapid and economical method is described for the determination of deltamethrin in wheat, rice, peanuts and corn. It is based on simultaneous extraction and clean-up on a column packed with alumina and silica gel using n-hexane-ethyl ether (8:2, v/v), followed by a derivatization step and gas-chromatographic analysis. Recoveries from fortified cereal and peanut samples were determined at four concentration levels and ranged from 73 to 109%. The detection limits were 0.01 to 0.03 mg/ kg. This method simplifies the traditional procedures in terms of sample size, solvent consumption and analysis time. Received: 25 March 1997 / Revised: 3 June 1997 / Accepted: 4 June 1997  相似文献   

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