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You searched for: Subject term esters Remove constraint Subject term: esters Subject term Helianthus annuus Remove constraint Subject term: Helianthus annuus Text availability Citation in PubAg Remove constraint Text availability: Citation in PubAg
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1. Intermittent frying effect on French fries in palm olein, sunflower, soybean and canola oils on quality indices, 3-monochloropropane-1,2-diol esters (3-MCPDE), glycidyl esters (GE) and acrylamide contents

Author:
Raznim Arni Abd Razak; Azmil Haizam Ahmad Tarmizi; Ainie Kuntom; Maimunah Sanny; Intan Safinar Ismail
Source:
Food control 2021 v.124 pp. 107887
ISSN:
0956-7135
Subject:
French fries; Helianthus annuus; acrylamides; alpha-chlorohydrin; canola oil; esters; fatty acid composition; food safety; fried foods; frying; frying oil; lipid peroxidation; oxidation; palm oils; sampling; soybeans; unsaturated fatty acids
Abstract:
... This study was carried out to determine the effect of intermittent frying of French fries using four different types of frying media on the media quality as well as 3-monochloropropane-1,2-diol esters (3-MCPDE) and glycidyl esters (GE) in frying oils and acrylamide contents in finished product. A total of 80 h of heating (control) and frying experiments at 180 °C was conducted, from which the heat ...
DOI:
10.1016/j.foodcont.2021.107887

2. Oleaginous feedstocks for hydro-processed esters and fatty acids (HEFA) biojet production in southeastern Brazil: A multi-criteria decision analysis

Author:
Lorena Mendes de Souza; Pietro A.S. Mendes; Donato A.G. Aranda
Source:
Renewable energy 2020 v.149 pp. 1339-1351
ISSN:
0960-1481
Subject:
Acrocomia; Helianthus annuus; Jatropha; biodiesel; castor beans; cotton; crops; esters; fatty acids; feedstocks; fuel production; multi-criteria decision making; peanuts; research and development; soybean oil; soybeans; Brazil
Abstract:
... This work establishes a ranking of the potential oleaginous feedstocks for HEFA biojet production in southeast Brazil, and consolidates their advantages and limitations, in order to assist in prioritizing strategic actions, such as research, R&D investment, and incentives for the most promising regional oilseeds. The oilseeds and the criteria considered were determined from a bibliographical revie ...
DOI:
10.1016/j.renene.2019.10.125

3. Sunflower (Helianthus annuus L.) Plants at Various Growth Stages Subjected to Extraction—Comparison of the Antioxidant Activity and Phenolic Profile

Author:
Francesco Gai; Magdalena Karamać; Michał A. Janiak; Ryszard Amarowicz; Pier Giorgio Peiretti
Source:
Antioxidants 2020 v.9 no.6 pp. -
ISSN:
2076-3921
Subject:
2,2-diphenyl-1-picrylhydrazyl; Helianthus annuus; aerial parts; antioxidant activity; caffeic acid; emulsions; esters; in vitro studies; isomers; late flowering; oxidation; quinic acid; tandem mass spectrometry
Abstract:
... The aim of this study was to evaluate the differences in the antioxidant activity and phenolic profile of sunflower (Helianthus annuus L.) extracts obtained from the aerial parts of plants harvested at five growth stages. In vitro assays were used to determine the antioxidant activity, i.e., ABTS•⁺ and DPPH• scavenging activity, the ferric-reducing antioxidant power (FRAP) and the ability to inhib ...
DOI:
10.3390/antiox9060535

4. Sunflower oil-based MCC surface modification to achieve improved thermomechanical properties of a polypropylene composite

Author:
W. S. M. Rathnayake; L. Karunanayake; A. M. P. B. Samarasekara; D. A. S. Amarasinghe
Source:
Cellulose 2020 v.27 no.8 pp. 4355-4371
ISSN:
0969-0239
Subject:
Helianthus annuus; X-ray diffraction; biodiesel; cellulose; crystal structure; esters; green chemistry; hardness; hydrophobicity; long chain fatty acids; polypropylenes; sunflower oil; thermal stability
Abstract:
... A biobased approach was taken to endow microcrystalline cellulose (MCC) with surface hydrophobicity using sunflower oil biodiesel (sunflower oil fatty acid ethyl esters, SFEEs) and thereby improve the compatibility with a hydrophobic polypropylene (PP) matrix. This environmentally friendly green chemistry approach introduces a monomolecular long-chain fatty acid layer on the MCC surface, making th ...
DOI:
10.1007/s10570-020-03053-5

5. Effect of Sunflower Collets Moisture on Extraction Yield and Oil Quality

Author:
Ethel E. Pérez; Erica R. Baümler; Guillermo H. Crapiste; Amalia A. Carelli
Source:
European journal of lipid science and technology 2019 v.121 no.2 pp. e1800234
ISSN:
1438-7697
Subject:
Helianthus annuus; alpha-tocopherol; beta-tocotrienol; carbon; esters; hexane; phospholipids; scanning electron microscopy; sunflower oil; water activity; water content
Abstract:
... The aim of this work is to analyze the effect of moisture content of sunflower expanded material on the quality of the extracted oil by determining its wax, phospholipids, and tocopherol content and composition. Sunflower oil extraction is carried out in a batch extractor at 50 °C using hexane and three moisture levels (5.65, 12.40, and 18.92% dry basis). The increasing moisture content causes an ...
DOI:
10.1002/ejlt.201800234

6. Oxygenated sunflower biodiesel: Spectroscopic and emissions quantification under reacting swirl spray conditions

Author:
Cheng Tung Chong; Meng-Choung Chiong; Jo-Han Ng; Mooktzeng Lim; Manh-Vu Tran; Agustin Valera-Medina; William Woei Fong Chong
Source:
Energy 2019 v.178 pp. 804-813
ISSN:
0360-5442
Subject:
Helianthus annuus; air temperature; atomization; biodiesel; carbon monoxide; combustion; emissions; esters; free radicals; liquids; nitric oxide; spectroscopy; viscosity
Abstract:
... The spray combustion characteristics of sunflower (Helianthus annuus) biodiesel/methyl esters (SFME) and 50% SFME/diesel blend and diesel were investigated via a liquid swirl flame burner. The swirl flame was established at atmospheric condition by using a combined twin-fluid atomiser-swirler configuration at varied atomising air-to-liquid ratios (ALR) of 2.0–2.5. Diesel flame showed a sooty flame ...
DOI:
10.1016/j.energy.2019.04.201

7. Changes in physicochemical properties of biodiesel after degradation and remediation

Author:
V. F. Mello; T. C. Soares; M. G. Fonseca; L. N. Batista
Source:
International journal of environmental science and technology 2018 v.15 no.8 pp. 1713-1718
ISSN:
1735-1472
Subject:
Helianthus annuus; biodiesel; diesel fuel; distillation; esterification; esters; iodine value; models; oxidation; oxidative stability; remediation
Abstract:
... Biodiesel is the main substitute for petrodiesel being constituted by several alkyl esters including unsaturated compounds. It can undergo partial oxidation when stored for long periods and transported over long distances. The aims of this study were to analyze the impact of the oxidation process on the physicochemical properties of biodiesel and its remediation through distillation and esterifica ...
DOI:
10.1007/s13762-017-1551-4

8. Direct determination of 3-chloropropanol esters in edible vegetable oils using high resolution mass spectrometry (HRMS-Orbitrap)

Author:
Giulia Graziani; Anna Gaspari; Donato Chianese; Lanfranco Conte; Alberto Ritieni
Source:
Food additives & contaminants 2017 v.34 no.11 pp. 1893-1903
ISSN:
1944-0057
Subject:
Helianthus annuus; alpha-chlorohydrin; cooking fats and oils; corn; detection limit; esters; mass spectrometry; peanuts; seeds; supermarkets; vegetable oil
Abstract:
... A series of refined edible oils derived from mixed seeds, peanuts, corn, sunflower and palm obtained from the local supermarket were analyzed for their content of 3-MCPD esters. A direct analytical method for the determination of 3-monochloropropane-1,2-diol esters (3-MCPD esters) was applied to investigate the major MCPD esters found in common edible oils; in particular seven types of monoesters ...
DOI:
10.1080/19440049.2017.1368721

9. Characterization of a small acyl-CoA-binding protein (ACBP) from Helianthus annuus L. and its binding affinities

Author:
Jose A. Aznar-Moreno; Mónica Venegas-Calerón; Zhi-Yan Du; Rafael Garcés; Julian A. Tanner; Mee-Len Chye; Enrique Martínez-Force; Joaquín J. Salas
Source:
Plant physiology and biochemistry 2016 v.102 pp. 141-150
ISSN:
0981-9428
Subject:
Arabidopsis thaliana; Brassica napus; Helianthus annuus; Oryza sativa; acyl coenzyme A; binding capacity; calorimetry; cell structures; esters; phosphatidylcholines; sunflower oil; sunflower seed protein; tissues; titration
Abstract:
... Acyl-CoA-binding proteins (ACBPs) bind to acyl-CoA esters and promote their interaction with other proteins, lipids and cell structures. Small class I ACBPs have been identified in different plants, such as Arabidopsis thaliana (AtACBP6), Brassica napus (BnACBP) and Oryza sativa (OsACBP1, OsACBP2, OsACBP3), and they are capable of binding to different acyl-CoA esters and phospholipids. Here we cha ...
DOI:
10.1016/j.plaphy.2016.02.025

10. Antioxidant activity of alkyl hydroxytyrosyl ethers in unsaturated lipids

Author:
Rosa Cert; Andrés Madrona; José Luis Espartero; M. Carmen Pérez-Camino
Source:
Food & function 2015 v.6 no.6 pp. 1999-2007
ISSN:
2042-650X
Subject:
Helianthus annuus; alpha-tocopherol; antioxidant activity; esters; ethers; fish; nutritive value; oils; oxidation; phenol; polyunsaturated fatty acids; temperature
Abstract:
... The antioxidant activity of ethyl and octyl hydroxytyrosyl ethers toward lipids was determined using the Rancimat and open cup methods at high temperatures and 50 °C, respectively. The effect of the unsaturation of the matrix was evaluated using sunflower, soya, and fish refined oils. The antioxidant activities of alkyl hydroxytyrosyl ethers (HTy ethers), hydroxytyrosyl esters, and free hydroxytyr ...
DOI:
10.1039/c5fo00300h

11. Characterisation of traditional Macedonian edible oils by their fatty acid composition and their volatile compounds

Author:
Violeta Ivanova-Petropulos; Sasa Mitrev; Trajce Stafilov; Natalija Markova; Erich Leitner; Ernst Lankmayr; Barbara Siegmund
Source:
Food research international 2015 v.77 pp. 506-514
ISSN:
0963-9969
Subject:
Helianthus annuus; alcohols; aldehydes; alkanes; alkenes; alpha-linolenic acid; cooking fats and oils; esters; fatty acid composition; flavor compounds; furans; gas chromatography-mass spectrometry; headspace analysis; linoleic acid; linseed; linseed oil; odors; oleic acid; pumpkin oil; pumpkins; pyrazines; rapeseed; rapeseed oil; seeds; sesame seed; solid phase microextraction; sulfur; sunflower oil; sunflower seed; terpenoids; transesterification; volatile compounds
Abstract:
... The fatty acid composition and volatile compounds of selected traditional Macedonian edible oils of several varieties, including sunflower seeds, pumpkin seeds, flax seed, rapeseed and sesame seeds, were analysed. The fatty acid (FA) composition was determined by GC-FID analysis after transesterification into the corresponding methyl esters. α-Linolenic acid (C18:3) was the main unsaturated fatty ...
DOI:
10.1016/j.foodres.2015.08.014

12. Classification of unifloral honeys using multivariate analysis

Author:
Mircea Oroian; Sonia Amariei; Alice Rosu; Gheorghe Gutt
Source:
Journal of essential oil research 2015 v.27 no.6 pp. 533-544
ISSN:
2163-8152
Subject:
terpenoids; Helianthus annuus; essential oils; cluster analysis; liquid-liquid extraction; honey; alcohols; Acacia; glucose; acids; esters; multivariate analysis; fructose; aldehydes; gas chromatography-mass spectrometry; discriminant analysis; volatile compounds; principal component analysis; water content; provenance; physicochemical properties; color; ketones
Abstract:
... The aim of this study was to investigate the physicochemical properties (moisture content, conductivity, 5-HMF, fructose, glucose, L*, a* and b* color parameters) and volatile compounds of Romanian honeys. According to the melissopalynological analysis, the honey samples were of the following botanical origins: acacia, sunflower and tilia. Liquid–liquid extraction followed by GC-MS analysis was us ...
DOI:
10.1080/10412905.2015.1073183

13. A new FTIR method to monitor transesterification in biodiesel production by ultrasonication

Author:
Dolores Reyman; Adrián Saiz Bermejo; Inmaculada Ramirez Uceda; Miguel Rodriguez Gamero
Source:
Environmental chemistry letters 2014 v.12 no.1 pp. 235-240
ISSN:
1610-3653
Subject:
Fourier transform infrared spectroscopy; Helianthus annuus; biodiesel; catalysts; cooking fats and oils; esters; fossil fuels; gas chromatography; irradiation; mixing; pollution; prices; recycling; sunflower oil; transesterification; ultrasonic treatment
Abstract:
... New renewable fuels are urgently needed due to increasing fossil fuel pollution. Biodiesel, which contains alkyl esters produced by transesterification of oils, is an alternative fuel. Nevertheless, the main problem of biodiesel is its high price. Costs can be reduced by replacement of the current homogeneous catalysts by heterogeneous catalysts; however, research for new catalysts is actually slo ...
DOI:
10.1007/s10311-013-0440-4

14. Application of random forests to select premium quality vegetable oils by their fatty acid composition

Author:
Fang-fang Ai; Jun Bin; Zhi-min Zhang; Jian-hua Huang; Jian-bing Wang; Yi-zeng Liang; Ling Yu; Zhen-yu Yang
Source:
Food chemistry 2014 v.143 pp. 472-478
ISSN:
0308-8146
Subject:
Helianthus annuus; corn; esters; extra-virgin olive oil; fatty acid composition; models; oleic acid; principal component analysis; sampling; sesame oil; tea; vegetable oil
Abstract:
... In order to discriminate premium quality from inexpensive edible oils, the fatty acid profiles of tea, rapeseed, corn, sunflower and sesame oil were compared with the ones from extra virgin olive oil (EVOO). Fatty acid methyl esters were quantified by GC/MS. Principal component analysis (PCA) and random forests (RF) were applied to cluster the samples. RF showed a better ability of discrimination ...
DOI:
10.1016/j.foodchem.2013.08.013
PubMed:
24054269

15. Fuel properties of biodiesel from vegetable oils and oil mixtures. Influence of methyl esters distribution

Author:
G. Martínez; N. Sánchez; J.M. Encinar; J.F. González
Source:
Biomass and bioenergy 2014 v.63 pp. 22-32
ISSN:
0961-9534
Subject:
Brassica carinata; Cynara cardunculus; Helianthus annuus; Jatropha; acid value; biodiesel; combustion; equations; esters; fuel production; heat; iodine; pour point; rapeseed; raw materials; saponification; soybeans; sunflower oil; transesterification; vegetable oil; viscosity; water content
Abstract:
... In this work, the quality of biodiesel produced by basic transesterification from several vegetable oils (soybean, rapeseed, sunflower, high oleic sunflower, Cynara Cardunculus L., Brassica Carinata and Jatropha Curca) cultivated in Extremadura has been studied in detail. The influence of raw material composition on properties such as density, viscosity, cetane number, higher heating value, iodine ...
DOI:
10.1016/j.biombioe.2014.01.034

16. Novel Approach for Liquid–Liquid Phase Equilibrium of Biodiesel (Canola and Sunflower) + Glycerol + Methanol

Author:
Hakim Maziar; Abedini Najafabadi Hamed; Pazuki Gholamreza; Vossoughi Manouchehr
Source:
Industrial & Engineering Chemistry Research 2014 v.53 no.2 pp. 855-864
ISSN:
1520-5045
Subject:
Gibbs free energy; Helianthus annuus; biodiesel; canola; canola oil; chemistry; energy; engineering; esters; glycerol; methanol; models; potassium hydroxide; sunflower oil; temperature
Abstract:
... In this study, a novel experimental approach was used to overcome the lack of phase equilibrium information to obtain data that is more applicable to industrial situations. Liquid–liquid equilibrium (LLE) data, tie-lines, and phase boundaries were carried out for two systems of canola oil methyl esters (containing 1 wt % KOH) + glycerol + methanol and sunflower oil methyl esters (containing 1 wt % ...
DOI:
10.1021/ie4031902

17. Biodiesel Production by Ethanolysis of Various Vegetable Oils Using Calcium Ethoxide as a Solid Base Catalyst

Author:
G. Anastopoulos; G. S. Dodos; S. Kalligeros; F. Zannikos
Source:
International journal of green energy 2013 v.10 no.5 pp. 468-481
ISSN:
1543-5083
Subject:
Helianthus annuus; biodiesel; calcium; catalysts; cold; cottonseed; diesel fuel; esters; ethanol; ethanolysis; fatty acids; frying oil; olive oil; sunflower oil; temperature; transesterification; vegetable oil; viscosity
Abstract:
... In this study, fatty acid ethyl esters (FAEE) were produced from four different vegetable oils (sunflower, cotton seed, olive oil, and used frying oil) using calcium ethoxide as a heterogeneous solid base catalyst. The ester preparation involved a two-step transesterification reaction, followed by purification. The effects of the mass ratio of catalyst to oil, the molar ratio of ethanol to oil, an ...
DOI:
10.1080/15435075.2012.674081

18. Combustion and Emission Characteristics of a Diesel Engine Fuelled with Biodiesel Having Varying Saturated Fatty Acid Composition

Author:
Tamil Selvan; G. Nagarajan
Source:
International journal of green energy 2013 v.10 no.9 pp. 952-965
ISSN:
1543-5083
Subject:
Helianthus annuus; biodiesel; carbon; carbon monoxide; chemical bonding; combustion; diesel engines; emissions; esters; fatty acid composition; hydrogen; nitrogen oxides; palm oils; saturated fatty acids; smoke; sunflower oil; unsaturated fatty acids; vegetable oil
Abstract:
... The present work is concerned with the performance, emission, and combustion characteristics of vegetable oil esters with varying saturated and unsaturated fatty acid composition tested in a stationary direct injection compression ignition engine. Saturated fatty acids (SFAs) are long-chain carboxylic acids that usually have between 12 and 24 carbon atoms and have no double bonds. Unsaturated fatt ...
DOI:
10.1080/15435075.2012.732157

19. Application of a Handheld Portable Mid-Infrared Sensor for Monitoring Oil Oxidative Stability

Author:
Meghan Allendorf; Anand Subramanian; Luis Rodriguez-Saona
Source:
journal of the American Oil Chemists' Society 2012 v.89 no.1 pp. 79-88
ISSN:
0003-021X
Subject:
Carthamus tinctorius; Helianthus annuus; acid value; corn; cottonseed; equipment; esters; fatty acid composition; models; monitoring; multivariate analysis; oxidation; oxidative stability; peanuts; peroxide value; prediction; unsaturated fatty acids; vegetable oil
Abstract:
... This study evaluated the capabilities of a handheld mid-infrared (MIR) spectrometer combined with multivariate analysis to characterize oils, monitor chemical processes occurring during oxidation, and to determine fatty acid composition. Vegetable oils (corn, peanut, sunflower, safflower, cottonseed, and canola) were stored at 65 °C for 30 days to accelerate oxidation reactions. Aliquots were draw ...
DOI:
10.1007/s11746-011-1894-9

20. Effects of feeding increasing dietary levels of high oleic or regular sunflower or linseed oil on fatty acid profile of goat milk

Author:
A.L. Martínez Marín; P. Gómez-Cortés; G. Gómez Castro; M. Juárez; L. Pérez Alba; M. Pérez Hernández; M.A. de la Fuente
Source:
Journal of dairy science 2012 v.95 no.4 pp. 1942-1955
ISSN:
0022-0302
Subject:
Helianthus annuus; alfalfa hay; conjugated linoleic acid; diet; dry matter intake; esters; fatty acid composition; goat milk; goats; lactose; linseed oil; milk; milk fat; milk yield; polyunsaturated fatty acids; sunflower oil; vaccenic acid
Abstract:
... In this work, the effects of increasing amounts of 3 plant oils in diets on the fatty acid (FA) profile of goat milk were studied. The study consisted of 3 experiments, one per oil tested (linseed oil, LO; high oleic sunflower oil, HOSFO; and regular sunflower oil, RSFO). The 3 experiments were conducted successively on 12 Malagueña goats, which were assigned at random to 1 of 4 treatments: 0, 30, ...
DOI:
10.3168/jds.2011-4303
PubMed:
22459841

21. Different enzyme requirements for the synthesis of biodiesel: Novozym® 435 and Lipozyme® TL IM

Author:
Hernández-Martín, Estela; Otero, Cristina
Source:
Bioresource technology 2008 v.99 no.2 pp. 277-286
ISSN:
0960-8524
Subject:
Borago officinalis; Helianthus annuus; alcoholysis; biodiesel; enzymes; esters; ethanol; methanol; soybeans; vegetable oil
Abstract:
... Enzymatic syntheses of biodiesel via alcoholysis of different vegetable oils (sunflower, borage, olive and soybean) have been studied. Loss of lipase activity induced by the nucleophile is greater with methanol than with ethanol, and is greater for Lipozyme® TL IM than for Novozym® 435. The optimum volume of ethanol depends on the loading of solid biocatalyst and is higher for preparations of Novo ...
DOI:
10.1016/j.biortech.2006.12.024

22. Comparative Efficacy of Systemic Acquired Resistance-Inducing Compounds Against Rust Infection in Sunflower Plants

Author:
Amzalek, E.; Cohen, Y.
Source:
Phytopathology 2007 v.97 no.2 pp. 179-186
ISSN:
0031-949X
Subject:
Helianthus annuus; signs and symptoms (plants); cell growth; butyric acid; plant pathogenic fungi; Puccinia helianthi; systemic acquired resistance; disease resistance; mycelium; leaves; defense mechanisms; callose; pathogenicity; gamma-aminobutyric acid; lignin; rust diseases; biosynthesis; salicylates; phenolic compounds
Abstract:
... Four inducers of systemic acquired resistance (SAR) were examined for their efficacy in controlling rust infection caused by Puccinia helianthi in sunflower plants. Of the four compounds, DL-3-amino-n-butanoic acid (DL-beta-aminobutyric acid [BABA]) was the most effective and sodium salicylate (NaSA) was the least effective in protecting against rust. In leaf disk assays, full protection was obtai ...
DOI:
10.1094/PHYTO-97-2-0179
PubMed:
18944373

23. Lipids as renewable resources: current state of chemical and biotechnological conversion and diversification

Author:
J. O. Metzger; U. Bornscheuer
Source:
Applied microbiology and biotechnology 2006 v.71 no.1 pp. 13-22
ISSN:
0175-7598
Subject:
Calendula officinalis; Coriandrum sativum; Helianthus annuus; Santalum album; Vernonia; amines; bitumen; byproducts; castor oil; chemical industry; electric utilities; epoxidation reactions; erucic acid; esters; fatty alcohols; free fatty acids; glycerol; industrial applications; linoleic acid; linolenic acid; linseed; lubricants; organic chemistry; rapeseed; raw materials; renewable resources; ricinoleic acid; soybeans; tung oil; vegetable oil; vernolate
Abstract:
... Oils and fats are the most important renewable raw materials of the chemical industry. They make available fatty acids in such purity that they may be used for chemical conversions and for the synthesis of chemically pure compounds. Oleic acid (1) from “new sunflower,” linoleic acid (2) from soybean, linolenic acid (3) from linseed, erucic acid (4) from rape seed, and ricinoleic acid (5) from cast ...
DOI:
10.1007/s00253-006-0335-4

24. Increasing control reliability of Orobanche cumana through integration of a biocontrol agent with a resistance-inducing chemical

Author:
Muller-Stover, D.; Buschmann, H.; Sauerborn, J.
Source:
European journal of plant pathology 2005 v.111 no.3 pp. 193-202
ISSN:
0929-1873
Subject:
weeds; parasitic plants; Orobanche cernua; fungal diseases of plants; biological control; biological control agents; Fusarium oxysporum; integrated weed management; induced resistance; esters; Helianthus annuus; pot culture; reliability

25. Changes of free and conjugated abscisic acid and phaseic acid in xylem sap of drought-stressed sunflower plants

Author:
Hansen, H.; Dorffling, K.
Source:
Journal of experimental botany 1999 v.50 no.339 pp. 1599-1605
ISSN:
0022-0957
Subject:
Helianthus annuus; abscisic acid; xylem; sap; drought; water stress; quantitative analysis; metabolites; esters; chemical constituents of plants
Abstract:
... Abscisic acid (ABA), conjugated abscisic acid, phaseic acid (PA), and conjugated phaseic acid were determined by enzyme-linked immunosorbent assay (ELISA) and gas chromatography (GC) in xylem sap of well-watered and drought-stressed sunflower plants. Conjugated ABA and conjugated PA were determined indirectly after chemical or enzymatic hydrolysis. Conjugated ABA was found to be the predominant AB ...
DOI:
10.1093/jxb/50.339.1599

26. Importance of the chiral centers of jasmonic acid in the responses of plants. Activities and antagonism between natural and synthetic analogs

Author:
Holbrook, L.; Tung, P.; Ward, K.; Reid, D.M.; Abrams, S.; Lamb, N.; Quail, J.W.; Moloney, M.M.
Source:
Plant physiology 1997 v.114 no.2 pp. 419-428
ISSN:
0032-0889
Subject:
Helianthus annuus; Brassica napus; measurement; chemical degradation; dose response; jasmonic acid; gene expression; Triticum aestivum; Nicotiana tabacum; esters; stereochemistry; enzyme activity; chemical structure; seed germination; transgenic plants; cotyledons; proteinase inhibitors; reporter genes; chemical constituents of plants; chlorophyll; beta-glucuronidase
Abstract:
... The importance of the two chiral centers at C-3 and C-7 in the molecular structure of jasmonic acid in plant responses was investigated. We separated methyl jasmonate (MeJA) into (3R)- and (3S)-isomers with a fixed stereochemistry at C-3, but epimerization at C-7 is possible. The four isomers of the nonepimerizable analog 7-methyl MeJA were synthesized. These six esters and their corresponding aci ...