Human appropriation of net primary production     

Haberl H  Krausmann F  Erb KH  Schulz NB 《Science (New York, N.Y.)》2002,296(5575):1968-9; author reply 1968-9

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Effects of different cooking procedures on lipid quality and cholesterol oxidation of farmed salmon fish (Salmo salar)     

Al-Saghir S  Thurner K  Wagner KH  Frisch G  Luf W  Razzazi-Fazeli E  Elmadfa I 《Journal of agricultural and food chemistry》2004,52(16):5290-5296

Salmon fillets were steamed, or pan-fried without oil, with olive oil, with corn oil, or with partially hydrogenated plant oil. The exchange between the salmon and the pan-frying oils was marginal, but it was detectable as slight modifications in the fatty acid pattern and the tocopherol contents according to the oil used. Primary and secondary oxidation products were only slightly increased or remained unchanged, which indicated a slight lipid oxidation effect due to the heating procedures applied. The same was observed for tocopherol levels, which remained almost stable and were not affected by the oxidation process. The sum of cholesterol oxidation products (COPs) increased after the heating processes from 0.9 microg/g in the raw sample to 6.0, 4.0, 4.4, 3.3, and 9.9 microg/g extracted fat in pan-fried without oil, with olive oil, corn oil, partially hydrogenated plant oil, and steamed, respectively. A highly significant correlation was found between the fatty acid pattern and the total amount of COPs (r2 = 0.973, p < 0.001). No change has been determined in the n-3 fatty acids content and in the polyunsaturated/saturated-ratio of the cooked salmon fillets. Moderate pan-frying (6 min total) and steaming (12 min) of salmon did not accelerate lipid oxidation but significantly increased the content of COPs. The highest increase of COPs was found through steaming, mainly due to the longer heat exposure. The used frying oils did not influence the outcome; no significant difference between heat treatment with or without oil has been determined.  相似文献   

Stereochemical course of the generation of 3-mercaptohexanal and 3-mercaptohexanol by beta-lyase-catalyzed cleavage of cysteine conjugates     

Wakabayashi H  Wakabayashi M  Eisenreich W  Engel KH 《Journal of agricultural and food chemistry》2004,52(1):110-116

The product resulting from the reaction between E-2-hexenal and l-cysteine was shown to be a diastereoisomeric mixture of 2-(2-S-l-cysteinylpentyl)-1,3-thiazolidine-4-carboxylic acid 1. Treatment of the conjugate with two sources of cysteine-S-conjugate beta-lyase (tryptophanase from E. coli and a crude enzyme extract prepared from Eubacterium limosum) resulted in the formation of 3-mercaptohexanal. The reaction proceeded with a slight preference for the (S)-configured product, however, with low conversion rate. The role of 3-S-l-cysteinylhexanal 2 as substrate for beta-lyases was demonstrated by in situ generation of 2 from 3-S-(N-acetyl-l-cysteinyl)hexanal using acylase. Opposite enantioselectivity was observed for the liberation of 3-mercaptohexanol from 3-S-l-cysteinylhexanol 5 by the enzyme preparations from Eubacterium limosum and tryptophanase. Various yeasts produced 3-mercaptohexanol starting from 1 as well as from 5. The reactions proceeded without preferential formation of one of the enantiomers.  相似文献   

Effects of chronic ingestion of ochratoxin a on blood levels and excretion of the mycotoxin in sheep     

Blank R  Rolfs JP  Südekum KH  Frohlich AA  Marquardt RR  Wolffram S 《Journal of agricultural and food chemistry》2003,51(23):6899-6905

Ruminants are relatively resistant to the acutely toxic effects of ochratoxin A, due to extensive degradation of ochratoxin A to its less toxic metabolite ochratoxin alpha by rumen microorganisms. However, most estimates of the degradation capacity for ochratoxin A in ruminants are based on in vitro studies. In the current study, the metabolism of ochratoxin A was investigated over a period of 29 days, feeding various doses of the mycotoxin (0, 9.5, 19.0, and 28.5 mug ochratoxin A/kg body weight) to sheep. Animals were fed diets consisting of 70% concentrates and 30% grass silage. Significant concentrations of undegraded ochratoxin A were detected in serum of sheep at all levels of ochratoxin A tested. Serum concentrations of ochratoxin A slightly accumulated with time of exposure and were linearly dependent on the administered dose of ochratoxin A. Furthermore, a constant proportion (6-8%) of the dose was excreted in the urine. The results of this study indicate that even at moderate to low levels of ochratoxin A in the diet, considerable amounts of the mycotoxin are absorbed by ruminants and may accumulate in tissues. Therefore, feeding of ochratoxin A-contaminated feedstuffs to ruminants does not seem to be a reliable means for using these feedstuffs.  相似文献   

Kapillarkonvolute an der Pleura parietalis der Ziege (Capra aegagrus hircus)     

Sabine  Blähser Karl-Heinz  Wille 《Anatomia, histologia, embryologia》1979,8(4):331-339

The aim of the present study was to describe the morphology and location of convoluted capillaries of the pleura in the goat. Seven adult male and female goats were (1) fixed by perfusion with formaldehyde or (2) perfused with Indian ink and postfixed in formaldehyde. The parietal pleura was studied systematically for the presence of convoluted capillaries; areas containing such formations were dissected out, counterstained and examined light microscopically. The convoluted capillaries occur (1) within the normal level of the vascular bed, or (2) in villous elevations. The presence of convoluted capillaries is discussed in correlation with the functional studies of Lang (1965).  相似文献   

Identification of a novel foot-and-mouth disease virus specific T-cell epitope with immunodominant characteristics in cattle with MHC serotype A31   总被引：2，自引：0，他引：2  

Gerner W  Carr BV  Wiesmüller KH  Pfaff E  Saalmüller A  Charleston B 《Veterinary research》2007,38(4):565-572

To identify foot-and-mouth disease virus (FMDV) specific T-cell epitopes within the entire polyprotein sequence of the virus, 442 overlapping pentadecapeptides were tested in proliferation assays using lymphocytes from cattle experimentally infected with FMDV. Four months post-infection cells from all investigated animals (n = 4) responded by proliferation and interferon-gamma production to a peptide located on the structural protein 1D (VP1), amino acid residues 66-80. Major histocompatibility complex (MHC) serotyping of the investigated cattle indicated that all animals shared the MHC serotype A31 which comprises the class II allele DRB3 0701. This may explain the common recognition of this newly discovered epitope. Responses to other peptides could only be observed in one animal and rapidly declined during the time course of the study. These observations point to an immunodominant role of this epitope located on the protein 1D in cattle with MHC serotype A31.  相似文献   

Metabolite profiling of colored rice (Oryza sativa L.) grains     

Thomas Frank  Bastian Reichardt  Qingyao Shu  Karl-Heinz Engel 《Journal of Cereal Science》2012

HPLC analysis of dehulled red, black and non-colored indica and japonica rice subspecies revealed significant differences in the contents of the anthocyanins cyanidin-3-glucoside and peonidin-3-glucoside. The rice materials were subjected to a comparative capillary gas chromatography-based metabolite profiling approach. The employed extraction and fractionation protocol enables the analysis of a broad spectrum of lipophilic and hydrophilic low molecular weight constituents from different chemical classes. The method covers not only primary metabolites (e.g. sugars, fatty acids) but also nutritionally relevant constituents (e.g. α-tocopherol, γ-aminobutyric acid). Statistical assessment of the data via principal component analysis and agglomerative hierarchical clustering revealed a distinct grouping of the different colored rice subspecies on the basis of their metabolite profiles. Compared to non-colored and red rice, black rice exhibited, in particular, higher levels of fatty acid methyl esters, free fatty acids, organic acids and amino acids.  相似文献   

Content of gamma-oryzanol and composition of steryl ferulates in brown rice (Oryza sativa L.) of European origin     

Miller A  Engel KH 《Journal of agricultural and food chemistry》2006,54(21):8127-8133

The content of gamma-oryzanol and the composition of steryl ferulates were determined in brown rice of European origin using on-line coupled liquid chromatography-gas chromatography (LC-GC). Analysis of 30 brown rice samples of various cultivars, grown at different sites and in different seasons, revealed the gamma-oryzanol content to range from 26 to 63 mg/100 g. Cycloartenyl ferulate and 24-methylenecycloartanyl ferulate were the major components of gamma-oryzanol followed by campesteryl ferulate, campestanyl ferulate, and beta-sitosteryl ferulate. The proportions of individual steryl ferulates exhibited enormous variability. However, irrespectively of the great variations observed for single steryl ferulates, the proportions of the sum of 4,4'-dimethylsteryl ferulates (cycloartenyl ferulate, 24-methylenecycloartanyl ferulate) and the sum of 4-desmethylsteryl ferulates (campesteryl ferulate, campestanyl ferulate, and beta-sitosteryl ferulate) were rather constant. The significant natural variability observed for gamma-oryzanol content and composition of steryl ferulates were shown to be influenced by environmental conditions but not by the degree of maturity of rice grains.  相似文献   

Application of two-dimensional gel electrophoresis to interrogate alterations in the proteome of genetically modified crops. 2. Assessing natural variability     

Ruebelt MC  Lipp M  Reynolds TL  Astwood JD  Engel KH  Jany KD 《Journal of agricultural and food chemistry》2006,54(6):2162-2168

Proteomics is currently tested as a complementary tool for the safety assessment of genetically modified (GM) crops. Understanding the natural variability of the proteome is crucial for the interpretation of biological differences between transgenic and nontransgenic parental lines. The natural variation of seed protein profiles among a set of 12 Arabidopsis thaliana ecotypes was determined by utilizing two-dimensional electrophoresis (2DE). The total number of different resolved protein spots found among the 12 ecotypes was 931 with a range of 573 (Mt-0) to 653 (Condara) in any one ecotype. Although the ecotypes were grown side-by-side in an environmentally controlled growth chamber, almost half of the resolved spots varied with respect to their presence/absence, and 95% of the spots present in all ecotypes varied in spot quantity (2-53-fold). In the evaluation of unintended effects of genetic modification, it is concluded that the experimental design must account for existing natural variability, which, in the case of the expressed proteome, can be substantial.  相似文献   

Determination and levels of the biocide ortho-phenylphenol in canned beers from different countries     

Coelhan M  Bromig KH  Glas K  Roberts AL 《Journal of agricultural and food chemistry》2006,54(16):5731-5735

A method was developed for the determination of the biocide ortho-phenylphenol (biphenyl-2-ol; OPP) in beer, using deuterated OPP as an internal standard. A new liquid-liquid extraction procedure, employing acetonitrile, diethyl ether, and n-pentane, afforded rapid phase separation. The evaporated extract was derivatized with pentafluorobenzyl bromide in a water-acetonitrile mixture that was buffered with potassium carbonate, followed by extraction of the derivative into cyclohexane and analysis by gas chromatography-mass spectrometry in electron ionization mode. The method enables the detection of OPP in 50 mL of beer at concentrations as low as 0.1 microg/L and provides a linear range of quantification of 0.5-40 microg/L. Samples from 61 beers canned over the past 12 years and sold in 27 countries were analyzed for OPP. In 40 of them, the target compound was present at concentrations of 1.2-40 microg/L. Our investigations indicate that the ends of the cans, which contain sealing material presumably treated with OPP, are responsible for this contamination.  相似文献