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You searched for: Journal Journal of agricultural and food chemistry Remove constraint Journal: Journal of agricultural and food chemistry Publication Year 2001 Remove constraint Publication Year: 2001 Source 2001 v.49 no.11 Remove constraint Source: 2001 v.49 no.11
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1. Acid hydrolysis of secoiridoid aglycons during storage of virgin olive oil

Author:
Brenes, M.; Garcia, A.; Garcia, P.; Garrido, A.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5609-5614
ISSN:
0021-8561
Subject:
olive oil; Olea europaea; varieties; food storage; phenolic compounds; acidity; oxygen; filtration
Abstract:
... The main change found in the phenolic composition of virgin olive oils of Arbequina, Hojiblanca, and Picual varieties during storage in darkness at 30 degrees C was the hydrolysis of the secoiridoid aglycons. This reaction gave rise to an increase in the free phenolics hydroxytyrosol and tyrosol in the oil. Filtration of oil and acidity influenced the hydrolysis to a large extent. Thus, the additi ...
DOI:
10.1021/jf0107860
PubMed:
11714367

2. Alfalfa (Medicago sativa L.) flavonoids. 2. Tricin and chrysoeriol glycosides from aerial parts

Author:
Stochmal, A.; Simonet, A.M.; Macias, F.A.; Oleszek, W.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5310-5314
ISSN:
0021-8561
Subject:
alfalfa; glycosides; food composition; spectral analysis; chemical constituents of plants
Abstract:
... Ten flavone glycosides have been isolated and identified in aerial parts of alfalfa. These included six tricin, one 3'-O-methyltricetin, and three chrysoeriol glycosides. Most of these compounds were acylated with ferulic, coumaric, or sinapic acids, and acylation occurred on the terminal glucuronic acid. Eight of these compounds, including 7-O-beta-D-glucuronopyranosyl-3'-O-methyltricetin, 7-O-be ...
DOI:
10.1021/jf010600x
PubMed:
11714321

3. Analysis of glycosidically bound aroma precursors in tea leaves. 3. Change in the glycoside content of tea leaves during the oolong tea manufacturing process

Author:
Wang, D.; Kubota, K.; Kobayashi, A.; Juan, I.M.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5391-5396
ISSN:
0021-8561
Subject:
tea; leaves; Camellia sinensis; flavor compounds; glycosides; food processing; odors
Abstract:
... A direct qualitative and quantitative determination of the glycosides of tea aroma compounds at the four stages of the oolong tea manufacturing process (plucking, solar withering, indoor withering, and oolong tea product) was carried out by a capillary gas chromatographic-mass spectrometric analysis after trifluoroacetyl derivatization of the glycosidic fractions. Sixteen glucosides and primeveros ...
DOI:
10.1021/jf010235+
PubMed:
11714333

4. Antioxidant activity and phenolic compounds in selected herbs

Author:
Zheng, W.; Wang, S.Y.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5165-5170
ISSN:
0021-8561
Subject:
medicinal plants; phenolic compounds; quantitative analysis; high performance liquid chromatography
Abstract:
... The antioxidant capacities (oxygen radical absorbance capacity, ORAC) and total phenolic contents in extracts of 27 culinary herbs and 12 medicinal herbs were determined. The ORAC values and total phenolic contents for the medicinal herbs ranged from 1.88 to 22.30 micromol of Trolox equivalents (TE)/g of fresh weight and 0.23 to 2.85 mg of gallic acid equivalents (GAE)/g of fresh weight, respectiv ...
DOI:
10.1021/jf010697n
PubMed:
11714298

5. Antioxidant mechanism of carnosic acid: structural identification of two oxidation products

Author:
Masuda, T.; Inaba, Y.; Takeda, Y.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5560-5565
ISSN:
0021-8561
Subject:
antioxidants; oxidation; chemical structure; Salvia officinalis; age; Rosmarinus officinalis; rosemary; reaction mechanisms; diterpenoids
Abstract:
... To determine the antioxidant mechanism of food phenolics against the oxidation of food components, the reaction of carnosic acid, an antioxidative constituent of the popular herbs sage and rosemary, was investigated in the presence of ethyl linoleate and the radical oxidation initiator 2,2'-azobis-(2,4-dimethylvaleronitrile). During this process, carnosic acid was oxidized to an o-quinone and a hy ...
DOI:
10.1021/jf010693i
PubMed:
11714360

6. Antioxidant properties of methanolic extracts from several ear mushrooms

Author:
Mau, J.L.; Chao, G.R.; Wu, K.T.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5461-5467
ISSN:
0021-8561
Subject:
mushrooms; Auricularia; antioxidants; medicinal properties; extracts
Abstract:
... Five kinds of ear mushrooms are commercially available in Taiwan, including black, red, jin, snow, and silver ears. Methanolic extracts were prepared from these ear mushrooms, and their antioxidant properties were studied. For all methanolic extracts from ear mushrooms, the antioxidant activities in the 1,3-diethyl-2-thiobarbituric acid method were moderate (38.6 approximately 74.6%) at 1.0-5.0 mg ...
DOI:
10.1021/jf010637h
PubMed:
11714344

7. Antioxidative activity of carbazoles from Murraya koenigii leaves

Author:
Tachibana, Y.; Kikuzaki, H.; Lajis, N.H.; Nakatani, N.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5589-5594
ISSN:
0021-8561
Subject:
spectral analysis; Bergera koenigii; leaves; plant extracts
Abstract:
... The antioxidative properties of the leaves extracts of Murraya koenigii using different solvents were evaluated based on the oil stability index (OSI) together with their radical scavenging ability against 1-1-diphenyl-2-picrylhydrazyl (DPPH). The methylene chloride (CH2Cl2) extract and the ethyl acetate (EtOAc) soluble fraction of the 70% acetone extract significantly prolonged the OSI values com ...
DOI:
10.1021/jf010621r
PubMed:
11714364

8. Assessing the aromatic potential of Cabernet Sauvignon and Merlot musts used to produce rose wine by assaying the cysteinylated precursor of 3-mercaptohexan-1-ol

Author:
Murat, M.L.; Tominaga, T.; Dubourdieu, D.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5412-5417
ISSN:
0021-8561
Subject:
wines; grape must; odors; cysteine; assays; food analysis
Abstract:
... The development of a method for assaying S-3-(hexan-1-ol)-L-cysteine, the cysteinylated precursor of 3-mercaptohexan-1-ol (P-3MH), in must has made it possible to study its impact on the aromatic potential of Merlot and Cabernet Sauvignon grape varieties used to produce rose wines in Bordeaux. The original feature of this method is the purification of very small volumes of must (500 microliter) co ...
DOI:
10.1021/jf0103119
PubMed:
11714336

9. Automated strong cation exchange extraction of fatty acid esters of 3-(N-phenylamino)-1,2-propanediol from oil samples for routine quantification by HPLC-APCI/MS/MS

Author:
Calaf, R.E.; Pena, J.; Paytubi, S.; Carrascal, M.; Posada, M.; Gelpi, E.; Abian, J.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5085-5091
ISSN:
0021-8561
Subject:
rapeseed oil; propanediols; fatty acid esters; automation; quantitative analysis; mass spectrometry; foodborne illness; high performance liquid chromatography; cation exchange
Abstract:
... Fatty acid esters of 3-(N-phenylamino)-1,2-propanediol are currently considered the best chemical markers of toxic oils related to the Spanish toxic oil syndrome. Recent research in this area has undertaken the exhaustive and quantitative characterization of these compounds in oils collected during the epidemic outbreak. Current methods developed in this laboratory are based on solid phase extract ...
DOI:
10.1021/jf0105541
PubMed:
11714286

10. Betalains--a new class of dietary cationized antioxidants

Author:
Kanner, J.; Harel, S.; Granit, R.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5178-5185
ISSN:
0021-8561
Subject:
antioxidants; diet; bioavailability; beets
Abstract:
... Antioxidant nutrients from fruits and vegetables are believed to be a class of compounds that exert their effects in humans by preventing oxidative processes which contribute to the onset of several degenerative diseases. This study found a new class of dietary cationized antioxidants in red beets (Beta vulgaris L.). These antioxidants are betalains, and the major one, betanin, is a betanidin 5-O- ...
DOI:
10.1021/jf010456f
PubMed:
11714300

11. Bioactive aromatic compounds from leaves and stems of Vanilla fragrans

Author:
Sun, R.; Sacalis, J.N.; Chin, C.K.; Still, C.C.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5161-5164
ISSN:
0021-8561
Subject:
stems; Culex pipiens; Vanilla planifolia; plant extracts; bioassays; spectral analysis; larvae; mortality; leaves; phenolic compounds
Abstract:
... Alcoholic extracts of leaves and stems of Vanilla fragrans were fractionated with ethyl acetate and aqueous butanol. All three fractions of ethyl acetate, butanol, and water were screened for toxic bioactivity against mosquito larvae. The results of these experiments showed that the fractions from the ethyl acetate and butanol phases were both active in the bioassay. Bioactivity of the ethyl aceta ...
DOI:
10.1021/jf010425k
PubMed:
11714297

12. Biological activity of total lipids from red and white wine/must

Author:
Fragopoulou, E.; Nomikos, T.; Tsantila, N.; Mitropoulou, A.; Zabetakis, I.; Demopoulos, C.A.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5186-5193
ISSN:
0021-8561
Subject:
wines; grape must; diet; lipids; heart diseases; platelet aggregation
Abstract:
... Wine is an essential component of the Mediterranean diet, and it is thought to exert a protective effect against coronary heart disease. Although many efforts have been made to determine the protective compounds in wines, their exact nature and how they are involved in the protection mechanisms are still unclear. In this study, total lipids, total polar lipids, and total neutral lipids of five win ...
DOI:
10.1021/jf0106392
PubMed:
11714301

13. Biomimetic transport of simple olive biophenol and analogues through model biological membranes by differential scanning calorimetry

Author:
Castelli, F.; Caruso, S.; Uccella, N.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5130-5135
ISSN:
0021-8561
Subject:
models; olives; thermodynamics; 4-hydroxybenzoic acid; calorimetry
Abstract:
... The different interactions of p-hydroxybenzoic acid (1), a simple biophenol (BP) found in olives and their food products, and its substitute analogues, benzoic (2), anisic (3), and toluic (4) acids, with a model membrane represented by dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles (MLV) was studied by differential scanning calorimetry (DSC). The influence of their different lipophil ...
DOI:
10.1021/jf0102867
PubMed:
11714292

14. Bleaching herbicide norflurazon inhibits phytoene desaturase by competition with the cofactors

Author:
Breitenbach, J.; Zhu, C.; Sandmann, G.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5270-5272
ISSN:
0021-8561
Subject:
norflurazon; enzyme inhibitors
Abstract:
... Cofactor requirement was determined for the heterologous expressed phytoene desaturases from the cyanobacterium Synechococcus and the higher plant Gentiana lutea. The cyanobacterial enzyme is dependent on either NAD(P) or plastoquinone, whereas only quinones such as plastoquinone can function as a cofactor for the phytoene desaturase from G. lutea. Enzyme kinetic studies were carried out to determ ...
DOI:
10.1021/jf0106751
PubMed:
11714315

15. Changes in the phenolic composition of virgin olive oil from young trees (Olea europaea L. cv. Arbequina) grown under linear irrigation strategies

Author:
Tovar, M.J.; Motilva, M.J.; Romero, M.P.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5502-5508
ISSN:
0021-8561
Subject:
tree age; phenolic compounds; irrigation; irrigation water; food composition
Abstract:
... This study reports the HPLC profiles of phenolic compounds of virgin olive oils obtained from young olive trees (Olea europaea L. cv. Arbequina) and how the application of a linear irrigation strategy affected these. Hydroxytyrosol, tyrosol, vanillic acid, vanillin, 4-(acetoxyethyl)-1,2-dihydroxybenzene, p-coumaric acid, the dialdehydic form of elenolic acid linked to hydroxytyrosol and to tyrosol ...
DOI:
10.1021/jf0102416
PubMed:
11714351

16. Characterization of espresso coffee aroma by static headspace GC-MS and sensory flavor profile

Author:
Maeztu, L.; Sanz, C.; Andueza, S.; Pena, M.P. de.; Bello, J.; Cid, C.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5437-5444
ISSN:
0021-8561
Subject:
coffee (beverage); flavor; flavor compounds; volatile compounds; roasting; Coffea arabica; Coffea canephora; correlation; principal component analysis; food analysis; food composition
Abstract:
... The aromas of three espresso coffee (EC) samples from different botanical varieties and types of roast (Arabica coffee, Robusta natural blend, and Robusta Torrefacto blend (special roast by adding sugar)) were studied by static headspace GC-MS and sensory flavor profile analysis. Seventy-seven compounds were identified in all of the EC samples. Among them, 13 key odorants have been quantified and ...
DOI:
10.1021/jf0107959
PubMed:
11714340

17. Characterization of soluble amaranth and soybean proteins based on fluorescence, hydrophobicity, electrophoresis, amino acid analysis, circular dichroism, and differential scanning calorimetry measurements

Author:
Gorinstein, S.; Delgado-Licon, E.; Pawelzik, E.; Permady, H.H.; Weisz, M.; Trakhtenberg, S.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5595-5601
ISSN:
0021-8561
Subject:
albumins; fluorescence; soybeans; Amaranthus hypochondriacus; amino acids; hydrophobicity; globulins; calorimetry; plant proteins
Abstract:
... Intrinsic fluorescence (IF), surface hydrophobicity (S(o)), electrophoresis, amino acid analysis, circular dichroism (CD), and differential scanning calorimetry (DSC) were used to study folded and unfolded soluble proteins from Amaranthus hypochondriacus (A. h.) and soybean (S). Globulin (Glo) and albumin subfractions (Alb-1 and Alb-2) were extracted from A. h. and S and denatured with urea. Elect ...
DOI:
10.1021/jf010627g
PubMed:
11714365

18. Chemical composition, nutritive value, and toxicology evaluation of Mexican wild lupins

Author:
Ruiz, M.A.; Sotelo, A.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5336-5339
ISSN:
0021-8561
Subject:
protein composition; Lupinus; seeds; wild plants; nutrient content; nutritive value; antinutritional factors; quinolizidine alkaloids; toxicity; chemical constituents of plants; Mexico
Abstract:
... The nutrient composition, toxic factors content, and nutritional and toxicological value of Lupinus splendens, L. rotundiflorus, L. elegans, L. simulans, L. exaltatus, L. reflexus, and L. madrensis species from Mexico were analyzed. The seeds of these species were a good source of protein. All the species showed a high lysine and tryptophan content, though sulfur amino acids were limiting. Cyanoge ...
DOI:
10.1021/jf010247v
PubMed:
11714325

19. Combinatorial synthesis and sensorial properties of polyfunctional thiols

Author:
Vermeulen, C.; Pellaud, J.; Gijs, L.; Collin, S.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5445-5449
ISSN:
0021-8561
Subject:
thiols; synthesis; odors; flavor compounds
Abstract:
... Over the past few years, polyfunctional thiols present as trace components have been found to play a major role in many food flavors, due to their exceptionally low odor thresholds. Unfortunately, their presence in minute concentration (in ng/kg to a few microgram/kg) and their high reactivity make it very difficult to extract and identify them. Furthermore, most of them are not yet commercially a ...
DOI:
10.1021/jf010816z
PubMed:
11714341

20. Comparison of the essential oils of Glehnia littoralis from northern and southern Japan

Author:
Miyazawa, M.; Kurose, K.; Itoh, A.; Hiraoka, N.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.11 pp. 5433-5436
ISSN:
0021-8561
Subject:
Apiaceae; essential oils; geographical distribution; chemical constituents of plants; Japan
Abstract:
... The essential oils from aerial and root parts of Glehnia littoralis were investigated by GC and GC-MS, and 125 compounds were identified. Plants were obtained from Northern and Southern Japan, and samples from the same locations were cultivated either exposed or unexposed to sunlight. The main constituents of the essential oils were found to be alpha-pinene (0.03-13.40%), limonene (0.15-10.71%), b ...
DOI:
10.1021/jf010219c
PubMed:
11714339