title: Enzymatic hydrolysis of phytate and effects on soluble oxalate concentration in foods.
abstract: Soluble oxalate in foods is major concern for kidney stone formers due to its tendency to increase urinary oxalate concentration. Phytate forms complexes with cations, which increases soluble oxalate by making cations unavailable to precipitate oxalate. Thus, in order to reduce soluble oxalate, bran samples (wheat, oat and barley) and bean samples (red kidney bean and white bean) were treated with phytase. Release of phosphate after phytate degradation and its association with calcium was determined. Phosphate concentration increased after application of phytase in all samples, but effect on soluble oxalate concentration varied. Wheat and oat bran showed significant reduction (P<0.05) in soluble oxalate compared to bean samples. Wheat bran, oat bran and white bean had a lower calcium:phosphate ratio than barley bran and red kidney beans. Correlation of the calcium:phosphate molar ratio with release of phosphate depends on concentration of calcium ions and this influences soluble oxalate concentration.
authors: Department of Food and Nutritional Sciences, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UK. Electronic address: israr.beenish@gmail.com.
authors: Beenish
authors: B
authors: Israr
authors: Department of Food and Nutritional Sciences, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UK.
authors: Richard A
authors: RA
authors: Frazier
authors: Department of Food and Nutritional Sciences, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UK.
authors: Michael H
authors: MH
authors: Gordon
mesh_terms: D010832:6-Phytase / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D007887:Fabaceae / Q000737:chemistry* / Q000187:drug effects; D001467:Hordeum / Q000737:chemistry* / Q000187:drug effects; D006868:Hydrolysis; D010070:Oxalates / Q000032:analysis*; D010833:Phytic Acid / Q000378:metabolism*; D014908:Triticum / Q000737:chemistry* / Q000187:drug effects
chemical_list: D010070:Oxalates; D010833:Phytic Acid; D010832:6-Phytase; D002118:Calcium
keywords: Enzyme hydrolysis; Kidney stones; Phytase; Phytate; Soluble oxalate