Even if plants can contain high levels of nitrate and nitrite, milk and dairy products are not described as sources of these anions. The purpose of this paper was to measure the concentrations of nitrate and nitrite in forage, cow blood, and milk.The results show that the nitrate ratio of milk to plasma is very low, suggesting that milk contamination with nitrate is unlikely to occur. This finding also proves the lack of an active transport mechanism to transfer nitrate from blood to milk. The nitrite anion almost disappears from milk through an enzymatic conversion; usually levels of μg l−1 were measured.
Authors:M. Croitoru, I. Fülöp, M. Ajtay, C. Balogh, and M. Dogaru
Artificial sweeteners were introduced in therapy as sugar substitutes for diabetic patients. Nowadays these substances are widely used for sugar substitution in low calorie drinks and sweets. Most commonly used products to date are saccharine, cyclamate, aspartame, and acesulfam; maximum accepted daily intakes are stated for each one.A simple reverse phase (RP18) HPLC-UV method with direct detection (196 nm) was developed by us in order to measure the concentrations of the three sweeteners. No sample preparation is required, other than dilution. Limits of detection are 12 mg l−1, 0.5 mg l−1 and lower than 0.25 mg l−1 for cyclamate, aspartame and saccharine, respectively. Concentrations ranged between 113.14–280.07 mg l−1 in the case of cyclamate, 17.96–50.94 mg l-1 for saccharine, and 9.94–296.82 mg l−1 for aspartame.
Authors:M. Croitoru, I. Fülöp, M. Ajtay, G. Dudutz, O. Crăciun, and M. Dogaru
To date, monosodium glutamate is the most used flavour enhancing food additive. Because high levels of glutamate are toxic to brain concerns appeared regarding the safe use of glutamate and there is a 10 g kg
concentration limit in foodstuff. A simple HPLC-UV method, based on a derivatization procedure with
-phthaldialdehyde, was developed for determination of glutamate in meat products, soup bases and vegetable concentrates. Even if our method is less sensitive than the HPLC-fluorescence ones widely available, it is able to measure amounts at least 200 times smaller than the maximum allowed one, has good reproducibility (CV under 2% for intraday and under 3% for interday determinations), linearity and accuracy. Less expensive HPLC systems are required and the formed derivative is very stable (at least 1 week), good separation is obtained with the less expensive 5 μm particle C
columns and methanol as organic phase. Concentration of free glutamate ranged between 0.14 g kg
in sausage without added glutamate to as high as 2.16 g kg
in a pork sausage. Concentration in vegetable mixes and soup bases were between 80–120 g kg
Authors:S. Younes, Márta Csire, Bernadett Pályi, G. Mikala, I. Vályi-Nagy, I. Cseh, Márta Benczik, Cs. Jeney, T. Takács, Éva Simon, V. Fülöp, G. Berencsi, Gy. Fekete, and Mária Visy
Pregnant women were examined following healthy pregnancies at term. Amniotic fluids were sampled before arteficial rupture of membranes using closed vacutainer system. Blood samples were also taken from the pregnants simultaneously.Endotoxin concentrations of amniotic fluids were tested by the semiquantitative Limulus amebocyte lysate. Both amniotic fluids and blood samples were tested for the presence of DNA of lymphotropic human herpesviruses. The DNA of human papillomaviruses were tested only in the amniotic fluid samples.One-third of the amniotic fluids tested were found to contain measurable amounts of endotoxin. Lymphotropic herpesvirus DNA was deteced in every fourth amniotic fluid sample and in every 8
blood sample. The prevalence of papillomaviruses was 7 of 96 samples.No significant correlation was found between the presence of endotoxin and viruses in the amniotic fluids. Epstein-Barr virus, human cytomegalovirus and human herpesvirus type 7 were found more frequently in the amniotic fluids than in blood samples (7 to 1). The prevalence of human herpesvirus 6 and 8 was higher in the blood samples than that in the amniotic fluids.The mean weight of the neonates were not impaired significantly by the presence of either viruses or endotoxin. Possible post partum consequences, i.e. partial immunotolerance to viruses is discussed.