The alpha-hydroxyacid 2-hydroxy-4-methylthiobutanoic acid (the so-called methionine hydroxy-analogue, MHA), largely used in animal nutrition as a source of methionine, forms stable metal chelates with divalent metals of formula [{CH3SCH2CH2CH(OH)COO}2M].nH2O. Protonation and iron(III) and copper(II) complex formation constants have been determined by pH-metry at 25 °C. In vivo investigations were carried out in the rat. After receiving a zinc-deficient diet for 3 weeks, animals were fed the same diet added with zinc sulfate or zinc/MHA chelate; the zinc content of faeces was higher (+ 45%; P < 0.05) in sulfate fed rats, whereas zinc retention was higher (+ 61%; P < 0.05) in the Zn/MHA diet. Moreover, experiments in vitro with human intestinal Caco-2 cells indicated that the MHA/Fe chelate was taken up by the cells without any apparent toxic effect.
Predieri G., Elviri L., Tegoni M., Zagnoni I., Cinti E., Biagi G., et al. (2005). Metal chelates of 2-hydroxy-4-methylthiobutanoic acid in animal feeding. Part 2: further characterizations, in vitro and in vivo investigations. JOURNAL OF INORGANIC BIOCHEMISTRY, 99, 627-636 [10.1016/j.jinorgbio.2004.11.011].
Metal chelates of 2-hydroxy-4-methylthiobutanoic acid in animal feeding. Part 2: further characterizations, in vitro and in vivo investigations
BIAGI, GIACOMO;
2005
Abstract
The alpha-hydroxyacid 2-hydroxy-4-methylthiobutanoic acid (the so-called methionine hydroxy-analogue, MHA), largely used in animal nutrition as a source of methionine, forms stable metal chelates with divalent metals of formula [{CH3SCH2CH2CH(OH)COO}2M].nH2O. Protonation and iron(III) and copper(II) complex formation constants have been determined by pH-metry at 25 °C. In vivo investigations were carried out in the rat. After receiving a zinc-deficient diet for 3 weeks, animals were fed the same diet added with zinc sulfate or zinc/MHA chelate; the zinc content of faeces was higher (+ 45%; P < 0.05) in sulfate fed rats, whereas zinc retention was higher (+ 61%; P < 0.05) in the Zn/MHA diet. Moreover, experiments in vitro with human intestinal Caco-2 cells indicated that the MHA/Fe chelate was taken up by the cells without any apparent toxic effect.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
