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1. Alterations of vitamin C, total phenolics, and antioxidant capacity as affected by processing tomatoes to different products

Author:
Gahler, S.; Otto, K.; Bohm, V.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7962-7968
ISSN:
0021-8561
Subject:
tomatoes; soups; food nutrient losses; vitamin content; phenolic compounds; tomato sauce; food composition; tomato juice; baking; antioxidant activity; ascorbic acid
Abstract:
... This study was conducted to investigate the antioxidant vitamin C, the polyphenol content, and the hydrophilic antioxidant capacity of tomato juice, baked tomatoes, tomato sauce, and tomato soup. During the production of tomato juice and during the preparation of the other tomato products, samples were taken after different times, respectively, after each particular production step. High-performan ...
DOI:
10.1021/jf034743q

2. A new LC/MS-method for the quantitation of acrylamide based on a stable isotope dilution assay and derivatization with 2-mercaptobenzoic acid. Comparison with two GC/MS methods

Author:
Jezussek, M.; Schieberle, P.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7866-7871
ISSN:
0021-8561
Subject:
acrylamides; chemical reactions; thiols; liquid chromatography; mass spectrometry; isotope dilution technique; carbon; stable isotopes; gas chromatography; food contamination; potato chips; cookies; quick breads; breadmaking
Abstract:
... Acrylamide (AA) was found to form a stable thioether in reasonable yields (45-50%) when reacted with 2-mercaptobenzoic acid at 20 °C for 3 h. On the basis of this finding and using [13C3]-acrylamide as the internal standard, a sensitive and selective new stable isotope dilution analysis for AA quantitation in food samples was developed based on single stage LC/MS. Comparison of the quantitative re ...
DOI:
10.1021/jf0349228

3. Anthocyanin transformation in Cabernet Sauvignon wine during aging

Author:
Wang, H.; Race, E.J.; Shrikhande, A.J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7989-7994
ISSN:
0021-8561
Subject:
wine aging; red wines; anthocyanins; chemical reactions; food composition; grapes
Abstract:
... Anthocyanins in Cabernet Sauvignon grapes and wines were elucidated by HPLC-MS/MS. Major anthocyanins in Cabernet Sauvignon grape extract are malvidin 3-O-glucoside and malvidin 3-O-acetylglucoside. In matured wine, anthocyanins are transformed to anthocyanin-vinyl derivatives, ethyl bridged anthocyanin-flavanol adducts, and anthocyanin-flavanol adducts. The major anthocyanin pigments are malvidin ...
DOI:
10.1021/jf034501q

4. Antioxidant activity of extracts, condensed tannin fractions, and pure flavonoids from Phaseolus vulgaris L. seed coat color genotypes

Author:
Beninger, C.W.; Hosfield, G.L.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7879-7883
ISSN:
0021-8561
Subject:
testa; proanthocyanidins; kidney beans; plant extracts; Phaseolus vulgaris; genotype; color; structure-activity relationships; flavonoids; antioxidant activity; antioxidants
Abstract:
... Twelve different seed coat color genotypes of Phaseolus vulgaris L. were extracted and pure flavonoids isolated from 10 of these. The seed coat methanol extracts, tannin fractions, and pure flavonoids all displayed antioxidant activity in a fluorescence-based liposome assay. The relatively high activity of the condensed tannin (proanthocyanidin) fractions indicates that these may play an important ...
DOI:
10.1021/jf0304324

5. Antioxidant constituents of radish sprout (kaiware-daikon), Raphanus sativus L

Author:
Takaya, Y.; Kondo, Y.; Furukawa, T.; Niwa, M.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8061-8066
ISSN:
0021-8561
Subject:
sprouts (food); free radicals; assays; radishes; sinapic acid; iron; antineoplastic agents; Raphanus sativus; food composition; flavonoids; antioxidant activity; glycosides
Abstract:
... Methanol extracts of 11 kinds of commonly available vegetables were examined for hydroxyl radical scavenging potency using the bleomycin-Fe method. In this method, the iron ion and bleomycin in water form hydroxyl radicals, and the scavenging activity is monitored by the modified thiobarbituric acid method. All extracts showed scavenging capacity, even though the activity of some of them was lower ...
DOI:
10.1021/jf0346206

6. Assessment of pesticide residues in honey samples from Portugal and Spain

Author:
Blasco, C.; Fernandez, M.; Pena, A.; Lino, C.; Silveira, M.I.; Font, G.; Pico, Y.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8132-8138
ISSN:
0021-8561
Subject:
honey; food contamination; organochlorine pesticides; carbamate pesticides; organophosphorus pesticides; pesticide residues; multiresidue analysis; solid phase extraction; gas chromatography; mass spectrometry; liquid chromatography; Spain; Portugal
Abstract:
... Fifty samples of honey collected from local markets of Portugal and Spain during year 2002 were analyzed for 42 organochlorine, carbamate, and organophosphorus pesticide residues. An analytical procedure based on solid-phase extraction with octadecyl sorbent followed by gas chromatography-mass spectrometry (GC-MS), for organochlorines, and by liquid chromatography-atmospheric pressure chemical ion ...
DOI:
10.1021/jf034870m

7. Biochemical properties of black drum and sheepshead seabream skin collagen

Author:
Ogawa, M.; Moody, M.W.; Portier, R.J.; Bell, J.; Schexnayder, M.A.; Losso, J.N.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8088-8092
ISSN:
0021-8561
Subject:
thermal stability; marine fish; protein secondary structure; collagen; Pogonias cromis; Archosargus probatocephalus; amino acid composition; molecular weight
Abstract:
... Acid-soluble collagen (ASC) and pepsin solubilized collagen (PSC) were isolated from the skins of black drum (Pogonias cromis) and sheepshead seabream (Archosargus probatocephalus) harvested in the Gulf of Mexico coastal waters. The yields of ASCs on dry basis from black drum and sheepshead were estimated at 2.3 and 2.6%, and the yields of PSCs were 15.8 and 29.3%, respectively. Analyses of molecu ...
DOI:
10.1021/jf034350r

8. Biodegradation kinetics of endosulfan by Fusarium ventricosum and a Pandoraea species

Author:
Siddique, T.; Okeke, B.C.; Arshad, M.; Frankenberger, W.T. Jr.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8015-8019
ISSN:
0021-8561
Subject:
soil bacteria; Fusarium; soil fungi; endosulfan; biodegradation; reaction kinetics; metabolites; bioremediation
Abstract:
... Endosulfan, classified as an organochlorine pesticide, is rated by the U.S. EPA as a Category 1 pesticide with extremely high acute toxicity. This study describes the biodegradation kinetics of endosulfan and the metabolic pathway utilized by Fusarium ventricosum and a Pandoraea sp. Complete disappearance of both α- and β-endosulfan was observed during 12 days of incubation with F. ventricosum in ...
DOI:
10.1021/jf030503z

9. Changes in macroscopic viscosity do not affect the release of aroma aldehydes from a pectinaceous food model system of low sucrose content

Author:
Bylaite, E.; Meyer, A.S.; Adler-Nissen, J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8020-8026
ISSN:
0021-8561
Subject:
pectins; thickeners; food additives; model food systems; volatilization; diffusivity; diffusion; volatile compounds; odors; aldehydes; sucrose; food composition
Abstract:
... The effects of pectin and viscosity on the release of a systematic series of aldehydes (alkanals, methyl-alkanals, alkenals, and alkandienals) were studied in a food model system of low sucrose content (10% w/w). The viscosity was varied by adding different amounts of Ca2+ (0, 13.5, and 27 mg/g pectin) to the model system of constant pectin concentration (0.4% w/w). Air-liquid partition coefficien ...
DOI:
10.1021/jf030455i

10. Characterization of a Fusarium 2-gene cluster involved in trichothecene C-8 modification

Author:
Brown, D.W.; Proctor, R.H.; Dyer, R.B.; Plattner, R.D.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7936-7944
ISSN:
0021-8561
Subject:
Fusarium graminearum; T-2 toxin; pseudogenes; biosynthesis; loci; structural genes; regulator genes; expressed sequence tags; cytochrome P-450; mutants; Fusarium sporotrichioides; promoter regions; acyltransferases
Abstract:
... The Fusarium trichothecenes T-2 toxin and deoxynivalenol (DON) are potent inhibitors of eukaryotic protein synthesis and are a significant agricultural problem. Three coregulated loci are required for T-2 toxin synthesis by Fusarium sporotrichioides. The core-trichothecene gene cluster consists of 12 genes (Tri3-Tri14) while the second locus consists of a single gene (Tri101). The third locus was ...
DOI:
10.1021/jf030607+

11. Characterization of lunasin isolated from soybean

Author:
Jeong, H.J.; Park, J.H.; Lam, Y.; De Lumen, B.O.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7901-7906
ISSN:
0021-8561
Subject:
protein synthesis; Glycine max; seeds; histones; anticarcinogenic activity; soybeans; plant extracts; seed development; bioassays; transfection; mice; acetylation; fibroblasts; oncogenes; cell proliferation; plant proteins
Abstract:
... Lunasin is a novel and promising chemopreventive peptide from soybean. We have shown previously that lunasin suppresses transformation of mammalian cells caused by chemical carcinogens and inhibits skin carcinogenesis in mice when applied topically. Although the lunasin gene was cloned from soybean, all experiments carried out so far in our lab have used synthetic lunasin and therefore there is no ...
DOI:
10.1021/jf034460y

12. Characterization of metabolites of hydroxycinnamates in the in vitro model of human small intestinal epithelium Caco-2 cells

Author:
Kern, S.M.; Bennett, R.N.; Needs, P.W.; Mellon, F.A.; Kroon, P.A.; Garcia-Conesa, M.T.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7884-7891
ISSN:
0021-8561
Subject:
hexosyltransferases; metabolism; caffeic acid; esterases; humans; sinapic acid; sulfotransferases; p-coumaric acid; intestinal mucosa; cell lines; enzyme activity; ferulic acid; small intestine; metabolites
Abstract:
... Hydroxycinnamic acids are antioxidant phenolic compounds which are widespread in plant foods, contribute significantly to total polyphenol intakes, and are absorbed by humans. The extent of their putative health benefit in vivo depends largely on their bioavailability. However, the mechanisms of absorption and metabolism of these phenolic compounds have not been described. In this study, we used t ...
DOI:
10.1021/jf030470n

13. Characterization of odor-active compounds in Californian Chardonnay wines using GC-olfactometry and GC-mass spectrometry

Author:
Lee, S.J.; Noble, A.C.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8036-8044
ISSN:
0021-8561
Subject:
white wines; volatile compounds; odors; gas chromatography; olfactometry; mass spectrometry; least squares; sensory evaluation; California
Abstract:
... Nineteen commercial Californian Chardonnay wines were analyzed by gas chromatography-mass spectrometry (GC-MS). Freon extracts of wines were separated by silica gel chromatography into three fractions. Volatiles were quantified by GC analysis of each fraction using internal standards added to the wine prior to Freon extraction. Twelve of the 19 wines were evaluated by GC-Olfactometry (GC-O). Of th ...
DOI:
10.1021/jf034747v

14. Combined influence of NaCl and sucrose on heat-induced gelation of bovine serum albumin

Author:
Baier, S.K.; McClements, D.J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8107-8112
ISSN:
0021-8561
Subject:
food processing; heat treatment; gelation; bovine serum albumin; sodium chloride; sucrose; denaturation; gels; rheological properties; turbidity
Abstract:
... The combined influence of a strongly interacting cosolvent (NaCl) and a weakly interacting cosolvent (sucrose) on the heat-induced gelation of bovine serum albumin (BSA) was studied. The dynamic shear rheology of 4 wt % BSA solutions containing 0 or 20 wt % sucrose and 0-200 mM NaCl was monitored as they were heated from 30 to 90 °C at 1.5 °C min-1, held at 90 °C for 120 min, and then cooled back ...
DOI:
10.1021/jf034249m

15. Composition and cellular localization of tannins in grape seeds during maturation

Author:
Geny, L.; Saucier, C.; Bracco, S.; Daviaud, F.; Glories, Y.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8051-8054
ISSN:
0021-8561
Subject:
Vitis vinifera; wine grapes; ripening; grape seeds; seed maturation; chemical constituents of plants; cell walls; tannins; proanthocyanidins; water stress; soil water deficit
Abstract:
... Cell walls were isolated from seeds of grape berries (Vitis vinifera L.), and proanthocyanidin composition was determined over the course of ripening for different levels of vine water status. During the ripening period the tannins from the cell walls were always more polymerized than those from the inner part of the cell. At maturity this difference becomes more significant compared to veraison, ...
DOI:
10.1021/jf030418r

16. Correlations between pulp properties of Eucalyptus clones and leaf volatiles using automated solid-phase microextraction

Author:
Zini, C.A.; Assis, T.F. de; Ledford, E.B. Jr.; Dariva, C.; Fachel, J.; Christensen, E.; Pawliszyn, J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7848-7853
ISSN:
0021-8561
Subject:
microextraction; sesquiterpenoids; hybrids; pulpwood; Eucalyptus; wood pulp; essential oils; principal component analysis; cluster analysis; volatile organic compounds; clones; automation; pulping; alpha-terpineol; mass spectrometry; gas chromatography; solid phase extraction; leaves
Abstract:
... Analysis of biogenic volatile organic compounds (BVOC) of 14 Eucalyptus clones has been performed using an automated headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography (GC)/ion trap mass spectrometry (ITMS) method. Correlations between pulp properties of Eucalyptus clones and the BVOC of their leaf headspaces were studied. The compounds α-terpineol and the sesquiterpene ...
DOI:
10.1021/jf034799k

17. Determination of total folate in plant material by chemical conversion into para-aminobenzoic acid followed by high performance liquid chromatography combined with on-line postcolumn derivatization and fluorescence detection

Author:
Zhang, G.F.; Maudens, K.E.; Storozhenko, S.; Mortier, K.A.; Straeten, D. van der; Lambert, W.E.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7872-7878
ISSN:
0021-8561
Subject:
tomatoes; food analysis; vitamin content; spinach; hydrogen peroxide; fluorescence; p-aminobenzoic acid; high performance liquid chromatography; cabbage; hydrochloric acid; folic acid; hydrolysis; carrots
Abstract:
... A procedure involving chemical conversion of all forms of folate present in plant material into para-aminobenzoic acid (PABA) and a liquid chromatographic-fluorimetric determination with on-line postcolumn derivatization is reported. All folates are cleaved with liberation of PABA by hydrogen peroxide followed by acid hydrolysis using concentrated hydrochloric acid (37%) at 110 °C for 6 h. The rea ...
DOI:
10.1021/jf034808p

18. Development of a microtiter plate ELISA and a dipstick ELISA for the determination of the organophosphorus insecticide fenthion

Author:
Cho, Y.A.; Kim, Y.J.; Hammock, B.D.; Lee, Y.T.; Lee, H.S.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7854-7860
ISSN:
0021-8561
Subject:
fenthion; insecticide residues; enzyme-linked immunosorbent assay; polyclonal antibodies; cross reaction; food analysis; food contamination; rice; lettuce
Abstract:
... In previous studies, polyclonal antibodies against the organophosphorus insecticide fenthion were obtained and an indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed for this pesticide. In this study, using these antibodies and an enzyme tracer, direct competitive ELISAs for fenthion in microtiter plate and dipstick formats were developed. The microtiter plate ELISA showed ...
DOI:
10.1021/jf0346915

19. Distribution of [14C]imidacloprid in sunflowers (Helianthus annuus L.) following seed treatment

Author:
Laurent, F.M.; Rathahao, E.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8005-8010
ISSN:
0021-8561
Subject:
inflorescences; Helianthus annuus; radionuclides; stems; isotope labeling; translocation (plant physiology); seed dressings; cotyledons; carbon; metabolites; imidacloprid; risk assessment; insecticide residues; nontarget organisms; pollen; leaves
Abstract:
... Imidacloprid, a neonicotinic insecticide, has been used as a seed dressing (Gaucho) to protect crops against soil and aerial insects. However, French beekeepers observed abnormal behavior of bees foraging on sunflowers and suspected a link between the imidacloprid seed treatment and the observed bee syndrome. This work studies the distribution of [14C-imidazolidin]imidacloprid (1mg/seed) in three ...
DOI:
10.1021/jf034310n

20. Effect of mild-heat and high-pressure processing on banana pectin methylesterase: a kinetic study

Author:
Ly-Nguyen, B.; Loey, A.M. van; Smout, C.; Verlent, I.; Duvetter, T.; Hendrickx, M.E.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7974-7979
ISSN:
0021-8561
Subject:
bananas; pectinesterase; enzyme inactivation; heat treatment; pressure treatment; food processing; thermodynamics; kinetics; enzyme activity
Abstract:
... Pectin methylesterase (PME) was extracted from bananas and purified by affinity chromatography. The thermal-high-pressure inactivation (at moderate temperature, 30-76 °C, in combination with high pressure, 0.1-900 MPa) of PME was investigated in a model system at pH 7.0. Under these conditions, the stable fraction was not inactivated and isobaric-isothermal inactivation followed a fractional-conve ...
DOI:
10.1021/jf034658i

21. Effect of pH on the thermal stability of potent roasty odorants, 3-mercapto-3-methylbutyl esters, in coffee drink

Author:
Kumazawa, K.; Masuda, H.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8032-8035
ISSN:
0021-8561
Subject:
coffee (beverage); canned foods; pH; heat stability; odors; volatile compounds; esters; food processing; heat treatment; canning
Abstract:
... The effect of pH on the thermal stability of potent roasty odorants, 3-mercapto-3-methylbutyl esters, in coffee drinks was investigated. The concentration of 3-mercapto-3-methylbutyl formate in the coffee drink was drastically decreased during the heat processing. However, the residual ratio of this compound in the coffee drink adjusted to pH 5.0 was higher than that of pH 6.5. On the other hand, ...
DOI:
10.1021/jf030458v

22. Evaluation of conventional and organic Italian foodstuffs for deoxynivalenol and fumonisins B1 and B2

Author:
Cirillo, T.; Ritieni, A.; Visone, M.; Cocchieri, R.A.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8128-8131
ISSN:
0021-8561
Subject:
breakfast cereals; rice; fumonisin B1; fumonisin B2; food contamination; corn; wheat; organic foods; deoxynivalenol; Italy
Abstract:
... Two lots of human foodstuffs from conventional and organic brand foods were purchased from supermarkets and analyzed for three Fusarium toxins, deoxynivalenol, by GC-ECD, and fumonisins B1 and B2 (FB1-FB2), by LC-MS. The occurrence of deoxynivalenol contamination was higher than 80% in both organic and conventional foods; fumonisin B1 was found in 20% of organic foods and in 31% of conventional on ...
DOI:
10.1021/jf030203h

23. Flavoring components of raw monsooned Arabica coffee and their changes during radiation processing

Author:
Variyar, P.S.; Ahmad, R.; Bhat, R.; Niyas, Z.; Sharma, A.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7945-7950
ISSN:
0021-8561
Subject:
Coffea arabica; coffee beans; food processing; food irradiation; gamma radiation; monsoon season; curing (crops); volatile organic compounds; flavor compounds; odors; caffeine; chlorogenic acid; caffeic acid; food composition
Abstract:
... Volatile aroma principles, nonvolatile taste constituents (caffeine and chlorogenic and caffeic acids), and glycosidically bound aroma compounds of monsooned and nonmonsooned raw arabica coffee were analyzed using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). Among the most potent odor active constituents known to contribute to the aroma of the gre ...
DOI:
10.1021/jf030408q

24. Influence of distillation system, oak wood type, and aging time on composition of cider brandy in phenolic and furanic compounds

Author:
Rodriguez Madrera, R.; Blanco Gomis, D.; Mangas Alonso, J.J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7969-7973
ISSN:
0021-8561
Subject:
temporal variation; gallic acid; vanillin; brandy; wood; food storage; storage time; furans; Quercus alba; distillation; food composition; apple cider; oak barrels
Abstract:
... A control of phenolic and furanic compounds in cider brandy was carried out during maturation in oak casks, studying three technological factors: distillation (rectification column vs double distillation), oak wood type (French vs American), and aging time (32 months). Gallic acid and benzoic and cinnamic aldehydes significantly increased during maturation of cider brandies, the highest level of t ...
DOI:
10.1021/jf0347618

25. Inhibition of reactive nitrogen species effects in vitro and in vivo by isoflavones and soy-based food extracts

Author:
Yen, G.C.; Lai, H.H.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7892-7900
ISSN:
0021-8561
Subject:
DNA damage; lipopolysaccharides; genistein; intraperitoneal injection; daidzein; soymilk; oral administration; nitrites; reaction inhibition; blood chemistry; macrophages; miso; tofu; tyrosine; oxidants; rats; antioxidant activity; nitric oxide; nitrogen; soybeans; amino acid derivatives; nitrates
Abstract:
... Recent studies have shown that soy isoflavone inhibits inducible nitric oxide (NO) synthase activities and is reported to have peroxynitrite scavenging ability. Consequently, we investigated whether isoflavones (daidzein and genistein) and extracts from soy-based products (miso, soymilk, tofu, soy sprout, black soybean, soybean, and yuba) would inhibit the reactive nitrogen species (RNS) effect in ...
DOI:
10.1021/jf034876b

26. Inhibitory effect of caffeic acid phenethyl ester on angiogenesis, tumor invasion, and metastasis

Author:
Liao, H.F.; Chen, Y.Y.; Liu, J.J.; Hsu, M.L.; Shieh, H.J.; Liao, H.J.; Shieh, C.J.; Shiao, M.S.; Chen, Y.J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7907-7912
ISSN:
0021-8561
Subject:
protein synthesis; caffeic acid; metalloproteinases; cytotoxicity; anticarcinogenic activity; adenocarcinoma; honey bees; propolis; metastasis; mice; esters; vascular endothelial growth factors; lungs; colorectal neoplasms; cell lines
Abstract:
... Caffeic acid phenethyl ester (CAPE) derived from honeybee propolis has been used as a folk medicine and has several proven biological activities. The present study investigated the effect of CAPE on angiogenesis, tumor invasion, and metastasis. A cytotoxicity assay of CAPE in CT26 colon adenocarcinoma cells showed a dose-dependent decrease in cell viability but no significant influence on the grow ...
DOI:
10.1021/jf034729d

27. Microwave-assisted headspace solid-phase microextraction for the analysis of bioemissions of bioemissions from Eucalyptus citriodora leaves

Author:
Xiong, G.; Goodridge, C.; Wang, L.; Chen, Y.; Pawliszyn, J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7841-7847
ISSN:
0021-8561
Subject:
Corymbia citriodora; leaves; gas emissions; volatile organic compounds; headspace analysis; microwave treatment; solid phase extraction; microextraction
Abstract:
... Microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) was developed as a simple and effective method for fast sampling of volatile organic compounds (VOCs) from Eucalyptus citriodora Hook (E. citriodora) leaves. During microwave heating, a simple shielding device made of aluminum foil was used to protect the SPME fiber from microwave irradiation while allowing the sample to be heat ...
DOI:
10.1021/jf0346105

28. Modulation of hepatic drug metabolizing enzymes and oxidative status by rooibos (Aspalathus linearis) and honeybush (Cyclopia intermedia), green and black (Camellia sinensis) teas in rats

Author:
Marnewick, J.L.; Joubert, E.; Swart, P.; Van der Westhuizen, F.; Gelderblom, W.C.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8113-8119
ISSN:
0021-8561
Subject:
Cyclopia; liver; green tea; glycosyltransferases; glutathione transferase; assays; medicinal plants; herbal tea; black tea; rats; enzyme activity; oral administration; antioxidant activity
Abstract:
... Rooibos and honeybush teas significantly (P < 0.05) enhanced the activity of cytosolic glutathione S-transferase alpha. A significant (P < 0.05) to marginal (P < 0.1) increase in the activity of the microsomal UDP-glucuronosyl transferase was obtained with unprocessed rooibos and honeybush teas, respectively. Oxidized glutathione (GSSG) levels were significantly (P < 0.05) reduced in the liver of ...
DOI:
10.1021/jf0344643

29. Molecular structures of fructans from Agave tequilana Weber var. azul

Author:
Lopez, M.G.; Mancilla-Margalli, N.A.; Mendoza-Diaz, G.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7835-7840
ISSN:
0021-8561
Subject:
Agave tequilana; fructans; fructooligosaccharides; carbohydrate structure; gas chromatography; mass spectrometry; nuclear magnetic resonance spectroscopy
Abstract:
... Agave plants utilize crassulacean acid metabolism (CAM) for CO2 fixation. Fructans are the principal photosynthetic products generated by agave plants. These carbohydrates are fructose-bound polymers frequently with a single glucose moiety. Agave tequilana Weber var. azul is an economically important CAM species not only because it is the sole plant allowed for tequila production but because it is ...
DOI:
10.1021/jf030383v

30. Multiple forms of xylose reductase in Candida intermedia: comparison of their functional properties using quantitative structure-activity relationships, steady-state kinetic analysis, and pH studies

Author:
Nidetzky, B.; Bruggler, K.; Kratzer, R.; Mayr, P.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7930-7935
ISSN:
0021-8561
Subject:
Candida; alcohol oxidoreductases; isozymes; enzyme activity; quantitative structure-activity relationships; enzyme kinetics; pH; binding capacity; NAD (coenzyme); NADP (coenzyme)
Abstract:
... The xylose-fermenting yeast Candida intermedia produces two isoforms of xylose reductase: one is NADPH-dependent (monospecific xylose reductase; msXR), and another is shown here to prefer NADH approximately equal to 4-fold over NADPH (dual specific xylose reductase; dsXR). To compare the functional properties of the isozymes, a steady-state kinetic analysis for the reaction D-xylose + NAD(P)H + H+ ...
DOI:
10.1021/jf034426j

31. Oil and squalene in Amaranthus grain and leaf

Author:
He, H.P.; Corke, H.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7913-7920
ISSN:
0021-8561
Subject:
lipid content; linoleic acid; seeds; Amaranthus; fatty acid composition; developmental stages; principal component analysis; seed oils; palmitic acid; chemical constituents of plants; squalene; oleic acid; leaves
Abstract:
... Amaranthus grain of 104 genotypes from 30 species was investigated for oil and squalene contents and fatty acid profiles. The overall average oil content in Amaranthus grain was 5.0%, ranging from 1.9 to 8.7%. Squalene concentration in extracted oils ranged from trace to 7.3%, with an average concentration of 4.2%. The average contents of three major fatty acids in Amaranthus grain were 22.2, 29.1 ...
DOI:
10.1021/jf030489q

32. On-line gas chromatography combustion/pyrolysis isotope ratio mass spectrometry (HRGC-C/P-IRMS) of pineapple (Ananas comosus L. Merr.) volatiles

Author:
Preston, C.; Richling, E.; Elss, S.; Appel, M.; Heckel, F.; Hartlieb, A.; Schreier, P.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8027-8031
ISSN:
0021-8561
Subject:
pineapple juice; volatile compounds; odors; flavor compounds; gas chromatography; pyrolysis; mass spectrometry; stable isotopes; carbon; deuterium
Abstract:
... By use of extracts prepared by liquid-liquid separation of the volatiles from self-prepared juices of pineapple fruits (Ananas comosus) (n = 14) as well as commercial pineapple recovery aromas/water phases (n = 3), on-line capillary gas chromatography-isotope ratio mass spectrometry was employed in the combustion (C) and the pyrolysis (P) modes (HRGC-C/P-IRMS) to determine the delta13C(VPDB) and d ...
DOI:
10.1021/jf030540q

33. Pressure/temperature combined treatment of precursors yield hormone-like peptides with pyroglutamate at the N terminus

Author:
Fernandez Garcia, A.; Butz, P.; Trierweiler, B.; Zoller, H.; Starke, J.; Pfaff, E.; Tauscher, B.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8093-8097
ISSN:
0021-8561
Subject:
chemical reactions; glutamine; food contamination; amino acid derivatives; food processing; pressure treatment; heat treatment; tripeptides; thyrotropin-releasing hormone
Abstract:
... Peptides containing the cyclic product of glutamine at the N terminus are usually biologically active. If the cyclization of glutamine was associated with a volume reduction, pressure should displace the equilibrium in the direction of the lower volume. Here, results in model solutions and in whey are discussed, showing that the theorized cyclization of glutamine in Gln-His-ProNH2 or Gln-Leu-ProNH ...
DOI:
10.1021/jf0348471

34. Principal component and linear discriminant analyses of free amino acids and biogenic amines in Hungarian wines

Author:
Heberger, K.; Csomos, E.; Simon-Sarkadi, L.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8055-8060
ISSN:
0021-8561
Subject:
white wines; red wines; food composition; free amino acids; biogenic amines; principal component analysis; discriminant analysis; wine cultivars; provenance; temporal variation; winemaking; Hungary
Abstract:
... Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to classify 187 Hungarian white and red wines according to wine-making technology, geographic origin (wine-making region), grape variety, and year of vintage based on free amino acid and biogenic amine contents. Determination of free amino acids and biogenic amines was accomplished by ion-exchange chromatography. S ...
DOI:
10.1021/jf034851c

35. Proanthocyanidin composition in the seed coat of lentils (Lens culinaris L.)

Author:
Duenas, M.; Sun, B.; Hernandez, T.; Estrella, I.; Spranger, M.I.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7999-8004
ISSN:
0021-8561
Subject:
epicatechin; testa; proanthocyanidins; food composition; catechin; lentils
Abstract:
... Lentils (Lens culinaris L.) are a popular food in many countries. However, little is known about their phenolic composition. Because polyphenols in lentils are located essentially in their seed coat, the objective of this work was to study the composition of proanthocyanidins, the major group of polyphenols, in this part of the tissue. The use of C18 Sep-Pak cartridges permitted the fractionation ...
DOI:
10.1021/jf0303215

36. Qualitative investigation on hydrothermal treatment of Hinoki (Chamaecyparis obtusa) bark for production of useful chemicals

Author:
Quitain, A.T.; Sato, N.; Daimon, H.; Fujie, K.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7926-7929
ISSN:
0021-8561
Subject:
myristic acid; Chamaecyparis obtusa; nontimber forest products; phenols; furfural; extraction; stearic acid; palmitic acid; temperature; hot water treatment; bark
Abstract:
... Hydrothermal treatment of an outer layer of a bark of Hinoki (Chamaecyparis obtusa) tree was investigated qualitatively for the possibility of utilizing residual forest biomass to produce valuable chemicals. Experiments were carried out in a semibatch reactor apparatus that allows the study of the effect of reaction temperatures in a single run. Gas chromatography-mass spectrometry analyses show t ...
DOI:
10.1021/jf021014m

37. Reaction of lentil trypsin-chymotrypsin inhibitors with human and bovine proteinases

Author:
Weder, J.K.P.; Kahleyss, R.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8045-8050
ISSN:
0021-8561
Subject:
trypsin; protein structure; trypsin inhibitors; humans; cattle; chymotrypsin; enzyme inhibition; antinutritional factors; binding sites; binding capacity; lentils
Abstract:
... Four trypsin-chymotrypsin inhibitors from Syrian local small lentils were selected to study the reasons for their different action against human and bovine proteinases. Chemical modification experiments, enzymatic modifications followed by carboxypeptidase degradation, and characterization of the inhibitor/enzyme complexes formed were performed. All four Lens culinaris inhibitors (LCI) contained a ...
DOI:
10.1021/jf0305682

38. Reactions of anthocyanins and tannins in model solutions

Author:
Salas, E.; Fulcrand, H.; Meudec, E.; Cheynier, V.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7951-7961
ISSN:
0021-8561
Subject:
procyanidins; tannins; anthocyanins; flavanols; chemical reactions; pH; red wines; color; absorbance; model food systems
Abstract:
... The reaction between procyanidin dimer Ec-EcG (B2 3'-O-gallate) and malvidin 3-O-glucoside (Mv3glc) was studied in a model solution system at two different pH values, 2.0 and 3.8. Disappearance of both species was much faster at pH 3.8 than at pH 2.0. That of Mv3glc was increased in the presence of Ec-EcG, whereas that of Ec-EcG was the same in the presence or absence of the anthocyanin. Values of ...
DOI:
10.1021/jf0345402

39. Size, stability, and entrapment efficiency of phospholipid nanocapsules containing polypeptide antimicrobials

Author:
Were, L.M.; Bruce, B.D.; Davidson, P.M.; Weiss, J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8073-8079
ISSN:
0021-8561
Subject:
lysozyme; dispersions; phosphatidylcholines; lipid composition; food preservation; encapsulation; food preservatives; cholesterol; particle size; phosphatidylglycerols; liposomes (artificial); nisin
Abstract:
... The effect of lipid composition [phosphatidylcholine (PC), phosphatidylglycerol (PG), and cholesterol] on size, stability, and entrapment efficiency of polypeptide antimicrobials in liposomal nanocapsules was investigated. PC, PC/cholesterol (70:30), and PC/PG/cholesterol (50:20:30) liposomes had entrapment efficiencies with calcein of 71, 57, and 54% with particle sizes of 85, 133, and 145 nm, re ...
DOI:
10.1021/jf0348368

40. Solid-phase microextraction and gas chromatography olfactometry analysis of successively diluted samples. A new approach of the aroma extract dilution analysis applied to the characterization of wine aroma

Author:
Marti, M.P.; Mestres, M.; Sala, C.; Busto, O.; Guasch, J.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7861-7865
ISSN:
0021-8561
Subject:
microextraction; sensory evaluation; food analysis; gas chromatography; headspace analysis; olfactometry; solid phase extraction; volatile organic compounds; odors; red wines
Abstract:
... The relationship between the composition and the aroma of the wine can be established by using gas chromatography with olfactometric detection (sniffing or GCO), which combines the chromatographic response with the human nose response. To evaluate the contribution of the odor compounds in wine aroma, we designed a new approach of the aroma extract dilution analysis (AEDA) that lies in the GCO anal ...
DOI:
10.1021/jf0345604

41. Steric effects governing disulfide bond interchange during thermal aggregation in solutions of β-lactoglobulin B and α-lactalbumin

Author:
Livney, Y.D.; Verespej, E.; Dalgleish, D.G.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8098-8106
ISSN:
0021-8561
Subject:
lactoglobulins; lactalbumin; heat treatment; protein aggregates; disulfide bonds; stereochemistry; cysteine; mass spectrometry; reversed-phase high performance liquid chromatography; ionic strength; chemical reactions; food processing
Abstract:
... Intermolecular disulfide bond formation in pure β-lactoglobulin (β-Lg) B and in its 1:1 mixture with α-lactalbumin (α-La), heated at 85 °C for 10 min in solutions of low and high (100 mM NaCl) ionic strength and pH 6.0, was studied by reverse-phase HPLC and MALDI-TOF mass spectrometry. Disulfide bonding between β-Lg monomers was more extensive than reported in the literature for a temperature of 6 ...
DOI:
10.1021/jf034582q

42. Supercritical carbon dioxide extraction of oil and squalene from Amaranthus grain

Author:
He, H.P.; Corke, H.; Cai, J.G.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7921-7925
ISSN:
0021-8561
Subject:
Amaranthus cruentus; seeds; seed oils; squalene; supercritical fluid extraction; carbon dioxide; pressure treatment; grinding; particle size; temperature
Abstract:
... Supercritical carbon dioxide (SC CO2) was used for the extraction of oil and squalene from Amaranthus grain. Very small amounts of oil could be extracted by SC CO2 from undisrupted grains, although SC CO2 possesses higher diffusivity. Grinding increased the extraction rate and oil yield, and smaller particle size gave higher extraction rate. The oil yield and initial extraction rate increased line ...
DOI:
10.1021/jf030488y

43. Superoxide radical scavenging activity of the major polyphenols in fresh plums

Author:
Chun, O.K.; Kim, D.O.; Lee, C.Y.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8067-8072
ISSN:
0021-8561
Subject:
anthocyanins; polyphenols; cultivars; cyanidin; plums; phenolic acids; chlorogenic acid; superoxide anion; antioxidant activity; quercetin
Abstract:
... The effect of polyphenols among different varieties of plums on superoxide radical scavenging activity (SRSA) was studied by an enzymatic method and their IC50 values were determined. We found that the SRSA levels of the polyphenols were closely related to their chemical structures; cyanidin showed the lowest IC50 among the polyphenols examined, and aglycones are more effective than their glycosid ...
DOI:
10.1021/jf034740d

44. Variation in cell wall composition among forage maize (Zea mays L.) inbred lines and its impact on digestiblity: analysis of neutral detergent fiber composition by pyrolysis-gas chromatography-mass spectrometry

Author:
Fontaine, A.S.; Bout, S.; Barriere, Y.; Vermerris, W.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8080-8087
ISSN:
0021-8561
Subject:
Zea mays; forage crops; in vitro digestibility; gas chromatography; neutral detergent fiber; phenolic acids; corn; genetic variation; inbred lines; pyrolysis; chemical constituents of plants; mass spectrometry; line differences; lignin
Abstract:
... Cell wall digestibility is an important determinant of forage quality, but the relationship between cell wall composition and digestibility is poorly understood. We analyzed the neutral detergent fiber (NDF) fraction of nine maize inbred lines and one brown midrib3 mutant with pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). Among 29 pyrolysis fragments that were quantified, two carbohyd ...
DOI:
10.1021/jf034321g

45. Variation in surface chemical constituents of cotton (Gossypium hirsutum) fiber as a function of maturity

Author:
Gamble, G.R.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7995-7998
ISSN:
0021-8561
Subject:
chemical composition; micronaire; electrical conductivity; lint cotton; salts; pectins; glucose; Gossypium hirsutum; maturity stage; surfaces; galacturonic acid; waxes
Abstract:
... Modern cotton yarn production technology has made it imperative that new predictors of yarn spinning efficiency be determined. Surface frictional forces play a large role in spinning efficiency, yet little is known about the chemical constituents comprising the cotton fiber surface or their respective roles in inter-fiber frictional behavior. Major cotton fiber surface chemical components includin ...
DOI:
10.1021/jf030178f

46. Volatile compounds and phenolic composition of virgin olive oil: optimization of temperature and time of exposure of olive pastes to air contact during the mechanical extraction process

Author:
Servili, M.; Selvaggini, R.; Taticchi, A.; Esposto, S.; Montedoro, G.F.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 7980-7988
ISSN:
0021-8561
Subject:
olives; food paste; olive oil; extraction; food processing; temperature; volatile compounds; phenolic compounds; food composition; cultivars; odors; sensory evaluation
Abstract:
... The operative conditions of malaxation such as temperature and time of exposure of olive pastes to air contact (TEOPAC) affect volatile and phenolic composition of virgin olive oil (VOO) and, as a consequence, its sensory and healthy qualities. In this paper, optimal temperature and TEOPAC during malaxation were studied, in lab scale, in two Italian cultivars using phenolic compounds, volatile com ...
DOI:
10.1021/jf034804k

47. Volatile organic compounds in foods: a five year study

Author:
Fleming-Jones, M.E.; Smith, R.E.
Source:
Journal of agricultural and food chemistry 2003 v.51 no.27 pp. 8120-8127
ISSN:
0021-8561
Subject:
foods; food contamination; organochlorine compounds; volatile organic compounds; gas chromatography; mass spectrometry; food analysis; longitudinal studies
Abstract:
... A purge and trap procedure was used with gas chromatography-mass spectrometry determination to analyze 70 foods for volatile organic compounds (VOCs). The results from analyses over a 5 year period (1996-2000) are reported. VOCs were found in at least one sample of all foods tested, although no single compound was found in each of the foods. The total amount of VOCs found in a single food item ove ...
DOI:
10.1021/jf0303159

48. Accuracy of dual energy X-ray absorptiometry (DXA), weight and P2 back fat to predict whole body and carcass composition in pigs within and across experiments

Author:
Suster, D.; Leury, B.J.; Ostrowska, E.; Bulter, K.L.; Kerton, D.J.; Wark, J.D.; Dunshea, F.R.
Source:
Livestock production science 2003 v.84 no.3 pp. 231-242
ISSN:
0301-6226
Subject:
X-radiation; backfat; body composition; body weight; bone density; computer software; dual-energy X-ray absorptiometry; energy; livestock production; mineral content; nondestructive methods; swine
Abstract:
... An Hologic QDR4500 dual energy X-ray absorptiometer (DXA) was used to measure body composition in 151 pigs ranging from 10 to 120 kg live weight. Large White×Landrace pigs of mixed sexes were selected from five different experiments to evaluate DXA accuracy within and across experiments. Values predicted by DXA including total tissue mass, fat tissue mass, lean tissue mass and bone mineral content ...
DOI:
10.1016/S0301-6226(03)00077-0

49. A 39 kDa protein mediates adhesion of avian Pasteurella multocida to chicken embryo fibroblast cells

Author:
Borrathybay, Entomack; Sawada, Takuo; Kataoka, Yasushi; Ohtsu, Naoko; Takagi, Masami; Nakamura, Shigeyuki; Kawamoto, Eiichi
Source:
Veterinary microbiology 2003 v.97 no.3-4 pp. 229-243
ISSN:
0378-1135
Subject:
Pasteurella multocida; agar; antiserum; bacteria; birds; blood serum; depolymerization; fibroblasts; glucose; heat; hyaluronic acid; hyaluronoglucosaminidase; outer membrane proteins; pathogenesis; polyacrylamide gel electrophoresis; rabbits; sodium chloride; starch; trypsin; virulence
Abstract:
... To clarify the role of avian Pasteurella multocida capsule in pathogenesis, adhesion of capsulated strains P-1059, X-73 and Pm-18, and noncapsulated strains P-1059B, Pm-1 and Pm-3 to chicken embryo fibroblast (CEF) cells was compared. Number of adherent organisms of the capsulated strains to CEF cells were approximately three times as much as noncapsulated strains indicating that adhesive properti ...
DOI:
10.1016/j.vetmic.2003.09.010

50. Beef production from Holstein–Friesian bulls and steers of New Zealand and European/American descent, and Belgian Blue×Holstein–Friesians, slaughtered at two weights

Author:
Keane, M.G.
Source:
Livestock production science 2003 v.84 no.3 pp. 207-218
ISSN:
0301-6226
Subject:
Belgian Blue; Holstein; artificial insemination; beef; beef cattle; bulls; carcass weight; commercial farms; cows; genetic merit; genotype; heifers; livestock production; longissimus muscle; meat production; natural mating; pastures; production technology; progeny; rearing; ribs; slaughter; slaughter weight; steers; subcutaneous fat; summer; Ireland; New Zealand
Abstract:
... Various strains of Holstein–Friesian cattle have been imported into Ireland in recent years. The objective of this study was to evaluate for beef production the male progeny of New Zealand (NZ) and European/American (EU) Holstein–Friesians, and Belgian Blue×Holstein–Friesians (BB). The NZ animals were imported from New Zealand as embryos which were implanted into Irish heifers. The EU animals were ...
DOI:
10.1016/S0301-6226(03)00092-7