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31.
Lipid separation from cheddar cheese whey allows a better valorization of protein fractions. In this study, bipolar membrane electroacidification (BMEA) was used to obtain precipitates with a high level of lipids. Whey samples with normal and low (by way of electrodialysis) mineral salt levels have been treated by a BMEA process and centrifuged. The composition of flocs and precipitation yields were determined. The BMEA process increased lipid precipitation rates by almost 50% in comparison with a centrifugation step only whereas a demineralization step prior to electroacidification had a limited effect on the precipitation level. Precipitates obtained were mainly composed of lipids (probably phospholipids) but also contained proteins. BMEA of cheddar cheese whey would allow the production of a lipid-enriched fraction and of a protein-enriched whey. 相似文献
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H. J. Miller J. D. Janse W. Kamerman P. J. Muller 《European journal of plant pathology / European Foundation for Plant Pathology》1980,86(2):55-68
Corynebacterium fascians, which causes leafy gall, has been shown to be responsible for the unusual symptoms recently found in lilies. The symptoms are described and the different bacterial isolates compared by biochemical, serological and pathogenicity experiments. No evidence could be found for the existence of specialized strains even though considerable variation in virulence could be demonstrated. Although the role of variation in susceptibility of the different lily cultivars should not be underestimated, it would appear that high inoculum levels ofC. fascians in the soil may be largely responsible for these outbreaks.Also included in this study are the results of biochemical, serological and pathogenicity experiments ofC. fascians which has been isolated fromKalanchoe, Euphorbia, Brodiaea, Hebe andVerbascum.Samenvatting Reeds een aantal jaren was in lelies een woekering in stengelbollen bekend, die echter sporadisch voorkwam en economisch van weinig betekenis was. Tijdens de zomer van 1977 echter trad de ziekte op één enkel perceel zo ernstig op dat zeer aanzienlijke oogstderving het gevolg was. Behalve de stengelbol kan ook de hoofdbol misvormd zijn. Bovendien kunnen misvormde stengelbollen lange spruiten vormen, zgn. sabeltandvorming. Soms is het wortelstelsel gereduceerd; in de kas zijn verdikte stengels waargenomen. De ziekte staat nu bekend onder de naam woekerziekte.Door de PD te Wageningen en het LBO te Lisse werd de bacterieCorynebacterium fascians (Tilford) Dows. uit het zieke materiaal geïsoleerd. In gezamenlijk onderzoek werd nagegaan of de bacterie de veroorzaker is van bovengenoemde symptomen en of hier sprake is van een op lelie gespecialiseerde stam.Biochemische en serologische vergelijkingen tussen isolaten vanC. fascians uit lelie,Kalanchoe, Euphorbia, Brodiaeea, Hebe enVerbascum laten zien dat er zeer weinig verschillen bestaan. Alle isolaten reageren op een standaard antiserum met titers variërend tussen 1: 640–1: 5120.Een oriënterende inoculatieproef werd uitgevoerd op het LBO in 1977. Daarna werden op de PD 10 van de 25 isolaten uit lelie en 8 uit andere waardplanten getoetst op lelie, chrysant en lathyrus. Uit de inoculatieproeven blijkt, dat de bacterie de veroorzaker is van de waargenomen symptomen. Tussen de isolaten blijkt een groot verschil in pathogeniteit te bestaan (12–100% aantasting), zonder dat dit aan herkomst gebonden is. Het voorkomen van op lelie of andere waardplanten gespecialiseerde stammen is daarom niet aan te nemen.In hoeverre de hevige aantasting een gevolg is van een opbouw van de bacterie-populatie door een te nauwe vruchtwisseling en mechanische rooimethoden moet worden nagegaan. 相似文献
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Muller JD Wilks CR O'Riley KJ Condron RJ Bull R Mateczun A 《Australian veterinary journal》2004,82(4):220-222
OBJECTIVE: To evaluate the specificity of an immunochromatographic test (ICT) for anthrax in cattle. DESIGN: A comparison of an ICT with blood smear and culture in uninfected cattle. PROCEDURE: Two hundred and forty blood samples were collected from dead cattle at two knackeries within Victoria and tested on-site with an ICT for the detection of protective antigen (PA) of Bacillus anthracis. Blood smears were prepared on-site and blood samples transported to the laboratory for aerobic and anaerobic culture. The results of the ICT were compared with blood smear and culture. Animals were regarded as not infected with B anthracis if the organism was not detected in a stained blood smear or on culture. Ten healthy yearling cattle were vaccinated with live spore anthrax vaccine and blood samples collected on days 0 to 7 and day 15 were tested in the ICT for the presence of PA. RESULTS: All blood samples from the 240 knackery cattle were ICT, smear and culture negative. All blood samples from the 10 vaccinated cattle were ICT negative. CONCLUSION: The ICT is a test with high specificity in cattle (98.5 to 100%; 95% CI) and recent vaccination of cattle does not give rise to positive reactions. 相似文献
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R.D. Jolly F.J. Allan M.G. Collett T. Rozaklis V.J. Muller J.J. Hopwood 《New Zealand veterinary journal》2013,61(5):144-148
Aim: To investigate the nature of a progressive ataxia in a New Zealand Huntaway dog. Methods: The affected dog was examined clinically before being humanely killed and necropsied. Selected tissues were submitted to light and electron microscopy and to biochemical analyses. Results: The histological lesions were interpreted as indicative of one of the forms of mucopolysaccharidosis type-III (dMPS-III), a lysosomal storage disease. Biochemically there was a deficiency of heparan sulphamidase. All the heparan sulphate chains had non-reducing-end glucosamine-N-sulphate residues. Conclusion: The disease is dMPS-IIIA (Sanfilippo syndrome). An autosomal recessive mode of inheritance can be provisionally assumed from the nature of this disease in other species. 相似文献
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Courant F Antignac JP Laille J Monteau F Andre F Le Bizec B 《Journal of agricultural and food chemistry》2008,56(9):3176-3184
In the present study, the occurrence of the main sex steroid hormones in milk, egg, and meat was evaluated on the basis of a highly specific gas chromatography-tandem mass spectrometry measurement method. Globally, the results indicated that targeted estrogens and androgens occurred at similar levels (concentration levels in the 10-100 ng kg (-1) range) in the analyzed muscle and milk samples. The same compounds occurred at about 10-fold higher concentrations (i.e., in the 100-1000 ng kg (-1) range) in eggs and kidney samples. More precisely, egg and milk appeared as a non-negligible sources of estradiol (i.e., 2.2 +/- 0.8 and 3.1 +/- 2.0 ng day (-1), respectively), whereas testosterone exposure is caused by ingestion of meat and/or egg (i.e., 12.2 +/- 48.2 and 5.2 +/- 2.3 ng day (-1), respectively). The provided exposure data will be further exploited in the scope of a risk assessment study regarding endocrine disruption associated with these molecules. 相似文献