Authors:Yvonne Anna Minar, Barbara Milz, and Bernd Spangenberg
We present a planar chromatographic separation method for the phytoestrogenic active compound equol, separated on RP-18 W (Merck, 1.14296) phase. It could be shown that an ethanolic cattle manure extract contains this phytoestrogenic active compound to a larger amount. As solvents for the mobile phase, hexane, ethyl acetate, and acetone (45:15:10, v/v); acetone and water (15:10, v/v); and n-hexane, CH2Cl2, ethyl acetate, methanol, and formic acid (40:40:20:5:1, v/v) have been used. After separation, a modified yeast estrogen screen (YES) test was applied, using the yeast strain Saccharomyces cerevisiae BJ3505 containing an estrogen receptor. Its activation by equol induces the reporter gene lacZ which encodes the enzyme β-galactosidase. The enzyme activity is measured directly on the TLC plate by using the substrate MUG (4-methylumbelliferyl-β-d-galactopyranoside) or the substrate X-β-Gal (5-bromo-4-chloro-3-indoxyl-β-d-galactopyranoside). β-Galactosidase cleaves MUG into a fluorescing compound. X-β- Gal is also hydrolyzed and then oxidized by oxygen forming the deep-blue dye 5,5′-dibromo-4,4′-dichloro-indigo. Both reactions in combination with a thin-layer chromatography (TLC) separation allow very specific detecting of equol in cattle manure, although that is a very challenging matrix. Preliminary results show that the average content of equol in liquid manure is roughly 60 μg g−1. The value for urine is 50 μg mL−1.
Authors:Robert A. Shanks and L. M. Wasantha K. Gunaratne
in reversing C p curves is due to a change in heat capacity due to plasticization, granule disruption, and melting of crystals. The lower temperature peak is associated with melting of amylopectin-based crystals while the higher temperature peak is
Authors:Radosław Łukasz Gwarda, Wojciech Szwerc, Monika Aletańska-Kozak, Anna Klimek-Turek, Andrzej Torbicz, Adam Chomicki, Ryszard Kocjan, Dariusz Matosiuk, and Tadeusz Henryk Dzido
In our previous papers, we have mentioned some specific disruption of peptide zones shape and chromatogram distortion, when using mobile phase containing ion-pairing acids. This problem is investigated here. It concerns not only some specific separation conditions but also various separation systems with silica-based adsorbents and water—alcohol mobile phases. We show that the problem results from significant amount of metallic impurities present in the adsorbents investigated. Our results prove that these impurities strongly affect the activity of free silanol groups and thus the retention of basic or amphoteric compounds and the quality of the results obtained. The standard method of washing adsorbent layer with methanol is not effective against the impurities. Washing chromatographic plates with a solution containing an acid significantly reduces the amount of metallic impurities in the adsorbent, resulting in the reduction/elimination of these adverse effects. However, it also leads to the increase of heterogeneity of acidic groups activity and deterioration of separation system efficiency. Therefore, removing metal ions from the adsorbent may not always be advantageous. Avoiding of use of strong ion-pairing acids is also problematic and not always possible. Thus, the production of high-purity silica of homogenous activity seems to be the best and the most reliable solution of the problem described.
leaches from can lining into food by contact during processing and production, storage conditions, and can lining decay by time [ 4 ]. Bisphenol A is an endocrine disruptor—a substance which interferes with the production, secretion, transport, action
The influence of -radiation on the structure of Langmuir-Blodgett (LB) layers of poly (3-hexadecylthiophene) in mixtures containing stearic and linolenic acids has been studied. The action of -photons leads to structural changes in the conducting polymer backbone as well as to disrupting oriented LB film structures.
Authors:T. Ohtsuki, K. Masumoto, K. Sueki, K. Shikano, and T. Shigematsu
Fullerenes, C60 and C70, were irradiated by 8 and 10 MeV deuterons. The irradiated samples were dissolved in CS2 and filtered to remove insoluble by-products. Finally, radioactive fullerenes and products, such as fullerene dimers, trimers
labeled with13N, were isolated and detected in the liquid phase by radiochromatography. This suggests that the energy rich13N atoms successfully incorporated into the fullerene cages and that the disrupted cages reacted with neighboring cages.
Authors:Irena Vovk, Breda Simonovska, Lidija Kompan, and Mirko Prošek
The ratio of lactulose/mannitol excretion in urine after their administration is of great importance for evaluation of malabsorption and intestinal permeability disruption in some diseases. An analytical method has been developed for determination of lactulose and mannitol in urine on the same amino HPTLC plate. The method enables densitometric quantification of lactulose by use of fluorescence mode, and mannitol by use of absorption mode after detection with AgNO
Forty elements were determined by instrumental neutron activation analysis in a wide range of Australian coals and fly ash to update and extend earlier measurements. The natural radioactivity content of selected samples were analysed by high resolution gamma-ray spectrometry and low level radiochemistry. The results indicated a marked disequilibrium of the232Th decay series in some samples while a general enrichment of210Pb in most fly ash samples disrupted the238U equilibrium.
Authors:Daniya Rakhmatullina, Alexander Alyabyev, Tatiana Ogorodnikova, and Anastasia Ponomareva
The effect of nitric oxide (NO) on heat production and oxygen consumption was studied in excised roots of 5-day-old wheat seedlings grown in CaCl2 solution (2.5 × 10−4 mol/L). Sodium nitroprusside (SNP), NaNO3, NaNO2 were used as NO donors. Incubation of the cut roots (wound stress) in the presence of NO donors led to the decrease of heat production and suppressed oxygen consumption. The increase of potassium (K+) ions exit was observed, pointing to the increase of the plasma membrane permeability and to the disruption of the adaptive processes development in roots in the NaNO2 presence.
Authors:T. Yoshida, T. Tanabe, A. Chen, Y. Miyashita, H. Yoshida, T. Hattori, and T. Sawasaki
The degradation and mineralization of dibutyl phthalate (DBP), one of endocrine disruptors, by g-ray irradiation were demonstrated. The degradation was enhanced by the effective energy conversion of g-rays to low-energy electrons and photons with the assistance of the interactions between g-rays and metals, which is especially in the case of high Z materials effective. Numerical simulations using EGS code supported the experimental results. Improvements of the energy conversion process are also suggested by controlling the shape of the metal and its spatial configuration in the DBP solution.