Search results for "MILK"
showing 10 items of 602 documents
H-2(d) mice born to and reared by HBeAg-transgenic mothers do not develop T cell tolerance toward the hepatitis B virus core gene products.
2000
The function of the secretory core gene product (HBeAg) of the human hepatitis B virus (HBV) is unknown. It has been proposed that this protein may be passed from the mother to her offspring at the perinatal stage where it might induce immune tolerance. In a previous study we have shown that the murine placenta presents an efficient barrier for the HBe protein and that H-2(b) mice born to HBeAg-positive transgenic mothers do not develop tolerance of specific cytotoxic T cells. In the present work we demonstrate that transgenic mice expressing high serum levels of HBeAg secrete only small amounts of this protein into their milk and excrete minute amounts of the viral gene product in their ur…
PCR-DGGE fingerprints of microbial succession during a manufacture of traditional water buffalo mozzarella cheese.
2004
D . E R C O L I N I , G . M A U R I E L L O , G . B L A I O T T A , G . M O S C H E T T I A N D S . C O P P O L A . 2003. Aims: To monitor the process and the starter effectiveness recording a series of fingerprints of the microbial diversity occurring at different steps of mozzarella cheese manufacture and to investigate the involvement of the natural starter to the achievement of the final product. Methods and Results: Samples of raw milk, natural whey culture (NWC) used as starter, curd after ripening and final product were collected during a mozzarella cheese manufacture. Total microbial DNA was directly extracted from the dairy samples as well as bulk colonies collected from the plates…
Streptococcus lactarius sp. nov., isolated from breast milk of healthy women.
2011
Three strains of a hitherto-unknown, Gram-stain-positive coccus were recovered from the milk of three non-related healthy women. The isolates shared 99% 16S rRNA gene sequence similarity with sequences from uncultured members of the Lactobacillales and Streptococcus. The closest sequence corresponding to a defined species was that of Streptococcus peroris GTC 848T, with a similarity of 98%. A partial sequence (488 bp) of the tuf gene also showed 97% similarity with that of S. peroris CCUG 39814T. The combined 16S rRNA/tuf-based phylogeny revealed that all the isolates grouped in a statistically well-supported cluster separate from S. peroris. Enzyme activity profiles as well as fermentation…
Staphylococcal food poisoning case and molecular analysis of toxin genes in Staphylococcus aureus strains isolated from food in Sicily, Italy.
2014
A case of staphylococcal food poisoning was observed in two individuals of the same family after consumption of primosale, a semiripened sheep cheese produced in Sicily. Staphylococcus aureus isolated from the cheese produced enterotoxin C (SEC) and carried both the enterotoxin C (sec) and the toxic shock syndrome toxin (tsst-1) gene. Following this case, an extensive survey was conducted on 971 food samples (raw milk, cheese, meat, and food preparations). S. aureus was detected in 102 of 971 food samples, from all types of food with the exception of ricotta cheese. The tsst-1 gene was present in 42% of the strains, either alone or in combination with other toxin genes. The enterotoxin C ge…
Immunochromatographic Assay for Quantitation of Milk Progesterone.
1996
We describe a rapid immunochromatographic method for the quantitation of progesterone in bovine milk. The method is based on a 'competitive' assay format using the monoclonal antibody to progesterone and a progesterone-protein conjugate labelled with colloidal gold particles. The monoclonal antibody to progesterone is immobilized as a narrow detection zone on a porous membrane. The sample is mixed with colloidal gold particles coated with progesterone-protein conjugate, and the mixture is allowed to migrate past the detection zone. Migration is facilitated by capillary forces. The amount of labelled progesterone-protein conjugate bound to the detection zone, as detected by photometric scann…
Direct determination of lead in human milk by electrothermal atomic absorption spectrometry
1999
Abstract Infants are particularly sensitive to the toxic effects of lead. Since milk is their only or main food it is important to know the contribution of milk to lead intake. The purpose of this study was to develop a direct method for determining the lead content of human milk by electrothermal atomic absorption spectrometry when a deuterium lamp is the only background correction available. The optimum conditions for lead determination in breast milk: sample dilution in Triton ×-100, modifier (75 μg of palladium) and nitric acid contents (2%) and the graphite furnace program (mineralization: 1100°C; atomization: 2300°C) were selected. The analytical parameters are: linearity (20–300 ng m…
Solid-phase extraction on C18 in the trace determination of selected polychlorinated biphenyls in milk.
1995
The utility of solid-phase extraction with octadecylsilica for determining fifteen polychlorinated biphenyl (PCB) congeners from milk samples was examined. Recoveries higher than 80% and relative standard deviations better than 10% were obtained for PCBs from different kinds of milk (whole, skimmed, 2%, powdered, breast and evaporated). A comparison with other procedures was made. The described method provides better detection limits than those attainable with the liquid-liquid extractions currently used as standard methods, when capillary gas-liquid chromatography is used for the final determination. A study of the separation was also performed using six different fused-silica capillary co…
Hydride generation atomic fluorescence spectrometric determination of ultratraces of selenium and tellurium in cow milk
2003
Abstract A sensitive procedure has been developed for selenium and tellurium determination in milk by hydride generation atomic fluorescence spectrometry (HG-AFS) after microwave-assisted sample digestion. The method provides sensitivity values of 1591 and 997 fluorescence units ng−1 ml−1 with detection limits of 0.005 and 0.015 ng ml−1 for Se and Te, respectively. The application of the developed methodology to the analysis of cow milk samples of the Spanish market evidenced the presence of concentration ranges from 11.1 to 26.0 ng ml−1 for Se, and from 1.04 to 9.7 ng ml−1 for Te having found a good comparability with data obtained after dry-ashing of samples.
Combining high performance thin layer chromatography with minispectrometer-fiber optic probe-coupled to smartphone for in place analysis: Lactose qua…
2021
ABSTRACT An in place colorimetric method has been proposed for estimation of the quantity of lactose in several matrix (milk, water effluents and surfaces). Analyzing the amount of this carbohydrate it can be control the product, the cleanliness of the parts of the dairy companies and it can avoid contamination of milk products produced there. This method combines the use of HPTLC for sugars separation with novel analytical devices as minispectrophotometer with fiber optic coupled to a smartphone. In order to measure the lactose a colorimetric reaction has been used. Variable volumes of samples or stock solutions were deposited in nano-silica gel layer, a mobile phase of acetonitrile:water:…
Simple liquid chromatography assay for analyzing ochratoxin A in bovine milk
2008
Abstract Ochratoxin A (OTA) is a mycotoxin with teratogenic and carcinogenic properties. Animal intake of feedstuffs contaminated with OTA may cause that some residues may be found in bovine milk, therefore, its analysis requires a highly sensitive, simple and precise technique. This method is based on a liquid–liquid extraction with methanol, followed by filtration and extract concentration. Liquid chromatography coupled to fluorescence detection was used for OTA analysis. In this way, several impurities are filtered off and OTA is quantified with a mean recovery of 93.0 ± 7.4% and a limit of detection of 0.01 ng mL −1 . Therefore, this methodology allows a simple quantitative extraction o…