ABSTRACT
Background: Siderophore is an iron chelator produced by microorganism. Pseudomonas aeruginosa produces two siderophores (pyoverdin and pyochelin). Desferrioxamine is a siderophore used in thalassemia patients to treat an iron overload of vital organs. Objective: Compare the ability of pyoverdin, pyochelin, and desferrioxamine for iron mobilization from ferritin. Materials and Methods: In vitro experiment, the ability of P. aeruginosa siderophores and desferrioxamine for iron mobilization from ferritin was compared by using a dialysis membrane assay at pH values of 7.4 and 6.0. Stimulation of P. aeruginosa PAO1 growth by all siderophores was studied in glucose minimum medium. Results: All three compounds were capable of iron mobilization at both pHs. At pH 6.0, the most effectiveness compound was desferrioxamine (31.6%), followed by pyoverdin (21.5%) and pyochelin (13.7%) compared on weight basis, each at 10 μg/mL. At equimolar concentration, their activities were desferrioxamine (38.5±1.2%), followed by pyoverdin (32.0±4.8%) and pyochelin (26.7±1.9%), respectively. Conclusion: The most effective compound in iron mobilization from ferritin was desferrioxamine, followed by pyoverdin and pyochelin respectively.
ABSTRACT
Absorption of nonheme iron has been studied extensively by the use of extrinsic tag radio-labeled iron to meals. Nevertheless, this method is unsuitable for screening large number of meals. The purpose of this study is to determine and compare iron availability from various kinds of meals in laboratory conditions that mimic the human stomach. Three hundred and seventy two common meals from the Siriraj Hospital kitchen were tested. The results of iron availability tests on the 372 Siriraj meals were classified as having low (5.77+2.42%), intermediate (12.42+1.55%), high (17.7+1.44%) and very high (25.8+3.65%) iron availability. Only meals of high and very high iron availability (22.1+4.99%) provided sufficient amounts of iron for the special requirement of teenagers and woman of childbearing age (2.22 to 3.24 mg of Fe per day) while meals of low and intermediate iron availability (8.12+3.84%) provided only 1.02 mg of iron per day. An average amount of estimated iron availability from the 372 meals was 14.12+8.2% of 1.77 mg per day. This was slightly inadequate because 2.06 to 2.15 mg were required per day for the high-risk groups. Results of this study indicated that 42.7% of Siriraj meals adequately provided the physiologic requirement of the high-risk segments of the population, but 57.3% of the meals did not. Improvement of food choices to increase dietary iron intake can be accomplished by including meat, fish or poultry and a source of vitamin C in every meal.