Solubility of Heme in Heme-Iron Enriched Bovine Hemoglobin Hydrolysates

详细信息    查看全文

• 作者：Fré ; dé ; ric Lebrun ; Anne Bazus ; Pascal Dhulster ; and Didier Guillochon
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：1998
• 出版时间：December 1998
• 年：1998
• 卷：46
• 期：12
• 页码：5017 - 5025
• 全文大小：157K
• 年卷期：v.46,no.12(December 1998)
• ISSN：1520-5118

文摘

A heme-iron enriched peptidic hydrolysate was prepared from bovine hemoglobin, at pilot plantscale, by peptic hydrolysis followed by ultrafiltration. Such preparations are attractive for irondeficiency therapy and have been reported in the literature in the context of utilization of blood inthe food industry. The peptidic fraction of this hydrolysate was able to solubilize heme in higherproportion than hemoglobin even at acidic pH where heme is totally insoluble. One peptide, havinga similar ability to solubilize heme in the same range of pH, was isolated from this fraction andtaken as a model to investigate the mechanisms involved in heme solubilization. Heme seemed tobe mainly solubilized through hydrophobic interactions with the peptide, whereas ligancies orelectrostatic interaction could not be demonstrated. The stoichiometry of heme-peptide adductsdepends on pH with a 2:2 association at pH 2 between heme as a dimer and two peptides and witha 2:1 association at pH 7.5 between one dimer and one single peptide. However, the existence ofhigher molecular weight aggregates cannot be excluded in the whole hemoglobin hydrolysate.Despite the good solubility of heme and the high heme/protein ratio, such heme enriched peptidichydrolysates could have a weak bioavailability since heme polymerization is known to decreaseheme-iron intestinal absorption. Further studies will be necessary to reduce heme polymerizationduring enzymatic hydrolysis of bovine hemoglobin.Keywords: Globin hydrolysate; heme-iron; hydrophobic interaction; iron deficiency