Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: dithiocarbamate

Sortuj według:

Ogranicz wyniki do:

Evaluation of p-phenylene-bis and phenyl dithiocarbamate sodium salts and inhibitors of mushroom tyrosinase

100%

Amin E. , Saboury A. A. , Mansouri-Torshizi H. , Zolghadri S. , Bordbar A.-K.

nr 3

Two structurally related compounds, phenyl dithiocarbamate sodium salt (I) and p-phenylene-bis (dithiocarbamate) sodium salt (II) were prepared by reaction of the parent aniline and p-phenylenediamine with CS2 in the presence of sodium hydroxide. These water soluble compounds were characterized by spectroscopic techniques, IR, 1H NMR and elemental analysis. The inhibitory effects of both compounds on both activities of mushroom tyrosinase (MT) from Agricus bisporus were studied at two temperatures, 27ºC and 37ºC. L-3, 4-dihydroxyphenylalanine (L-DOPA), and l-tyrosine were used as natural substrates for the catecholase and cresolase enzyme reactions, respectively. Kinetic analysis confirmed noncompetitive inhibition mode of I and mixed type of II on both activities of MT; I and II inhibit MT with inhibition constants (KI) of 300 μM and 4 μM, respectively. Analysis of thermodynamic parameters indicated predominant involvement of hydrophobic interactions in binding of I and electrostatic ones in binding of II to MT. It seems that II is a more potent MT inhibitor due to its two charged head groups able to chelate copper ions in the enzyme active site. Intrinsic fluorescence studies as a function of concentrations of both compounds showed unexpectedly quenching of emission intensity without any shift of emission maximum. Extrinsic ANS-fluorescence indicated that only binding of I induces limited changes in the tertiary structure of MT, in agreement with the postulated hydrophobic nature of the binding mechanism.

Dithiocarbamate residues in fruits, vegetables and herbs from the area of the south-eastern Poland in 2011−2013

88%

Podbielska M. , Szpyrka E. , Matyaszek A. , Kurdziel A. , Rupar J. , Slowik-Borowiec M.

Progress in Plant Protection

2014

tom 54

nr 3

In 2011–2013 in the Laboratory of Pesticide Residue Analysis of Plant Protection Institute – National Research Institute in Rzeszów 339 samples of fruits, vegetables and herbs were tested for the presence of dithiocarbamate fungicide residues. Dithiocarbamates were found in 27 (8.0%) analysed samples. No exceeding of Maximum Residue Levels (MRLs) was stated. Dithiocarbamates were detected most frequently in: gooseberries (45.4% of the samples of the crop), red currants (33.3%), black currants (29.6%), pears (18.7%) and peaches (14.3%).

W latach 2011–2013 w Laboratorium Badania Pozostałości Środków Ochrony Roślin Terenowej Stacji Doświadczalnej Instytutu Ochrony Roślin – Państwowego Instytutu Badawczego w Rzeszowie przebadano 339 próbek owoców, warzyw oraz upraw zielarskich na obecność pozostałości fungicydów ditiokarbaminianowych. W 27 (8,0%) badanych próbkach wykryto pozostałości ditiokarbaminianów. W żadnej z próbek nie stwierdzono przekroczenia najwyższych dopuszczalnych poziomów pozostałości (NDP). Ditiokarbaminiany wykrywano najczęściej w: agreście (45,4% badanych próbek tej uprawy), porzeczkach czerwonych (33,3%), porzeczkach czarnych (29,6%), gruszkach (18,7%) i brzoskwiniach (14,3%).

Badanie aktywnosci mutagennej fungicydow ditiokarbaminowych

63%

Chruscielska K. , Pluciennik H. , Kalhorn D. , Graffstein B.

nr 2

123-129