Dietary Aspergillus niger phytase increases iron absorption in humans

被引:131
作者
Sandberg, AS [1 ]
Hulthen, LR [1 ]
Turk, M [1 ]
机构
[1] GOTHENBURG UNIV,SAHLGRENS HOSP,DEPT CLIN NUTR,S-41345 GOTHENBURG,SWEDEN
关键词
phytase; phytate; iron absorption; humans;
D O I
10.1093/jn/126.2.476
中图分类号
R15 [营养卫生、食品卫生]; TS201 [基础科学];
学科分类号
100403 ;
摘要
Phytate is an inhibitor of iron absorption that can be removed before the intestinal site of absorption by microbial phytase, thereby increasing iron absorption from a meal. The effects of two kinds of dietary phytase, cereal phytase and microbial phytase from Aspergillus niger, on iron absorption were investigated. Iron absorption was measured from single meals containing white wheat rolls supplemented with wheat bran with or without phytase activity (expt. 1) and phytase-deactivated wheat bran with or without addition of microbial phytase from A. niger (expt. 2). Each experiment had 10 subjects and two different radio iron tracers: Fe-55 and Fe-59 were used for comparison of the absorption from the test meals in each experiment. No differences in iron absorption were found between meals containing wheat bran with or without phytase activity. Addition of microbial phytase to the meal containing phytase-deactivated wheat bran increased iron absorption from 14.3 +/- 2.6% to 26.1 +/- 3.8% (P < 0.0001). Two pH optima, one at pH 2.0 and one at pH 6.0, were found for A. niger phytase at 37 degrees C, but activity occurred at all pH values between 1.0 and 7.5. The results suggest that effective and complete degradation of phytate occurred in the stomach when A. niger phytase was given with the meal. This may be explained by high activity of microbial phytase at physiological pH conditions of the stomach, whereas wheat phytase has a different pH optimum.
引用
收藏
页码:476 / 480
页数:5
相关论文
共 21 条
[1]  
[Anonymous], IRON
[2]   FOOD IRON-ABSORPTION IN MAN - APPLICATIONS OF 2-POOL EXTRINSIC TAG METHOD TO MEASURE HEME AND NONHEME IRON-ABSORPTION FROM WHOLE DIET [J].
BJORNRASMUSSEN, E ;
HALLBERG, L ;
ISAKSSON, B ;
ARVIDSSON, B .
JOURNAL OF CLINICAL INVESTIGATION, 1974, 53 (01) :247-255
[3]   IRON-ABSORPTION FROM BREAD IN HUMANS - INHIBITING EFFECTS OF CEREAL FIBER, PHYTATE AND INOSITOL PHOSPHATES WITH DIFFERENT NUMBERS OF PHOSPHATE GROUPS [J].
BRUNE, M ;
ROSSANDERHULTEN, L ;
HALLBERG, L ;
GLEERUP, A ;
SANDBERG, AS .
JOURNAL OF NUTRITION, 1992, 122 (03) :442-449
[4]   AN IMPROVED METHOD FOR SIMULTANEOUS DETERMINATION OF IRON-55 AND IRON-59 IN BLOOD BY LIQUID SCINTILLATION COUNTING [J].
EAKINS, JD ;
BROWN, DA .
INTERNATIONAL JOURNAL OF APPLIED RADIATION AND ISOTOPES, 1966, 17 (07) :391-&
[5]   IRON-ABSORPTION IN MAN - ASCORBIC-ACID AND DOSE-DEPENDENT INHIBITION BY PHYTATE [J].
HALLBERG, L ;
BRUNE, M ;
ROSSANDER, L .
AMERICAN JOURNAL OF CLINICAL NUTRITION, 1989, 49 (01) :140-144
[6]   PHYTATES AND THE INHIBITORY EFFECT OF BRAN ON IRON-ABSORPTION IN MAN [J].
HALLBERG, L ;
ROSSANDER, L ;
SKANBERG, AB .
AMERICAN JOURNAL OF CLINICAL NUTRITION, 1987, 45 (05) :988-996
[7]   SOYBEAN PHYTATE CONTENT - EFFECT ON CALCIUM-ABSORPTION [J].
HEANEY, RP ;
WEAVER, CM ;
FITZSIMMONS, ML .
AMERICAN JOURNAL OF CLINICAL NUTRITION, 1991, 53 (03) :745-747
[8]   SOY PROTEIN, PHYTATE, AND IRON-ABSORPTION IN HUMANS [J].
HURRELL, RF ;
JUILLERAT, MA ;
REDDY, MB ;
LYNCH, SR ;
DASSENKO, SA ;
COOK, JD .
AMERICAN JOURNAL OF CLINICAL NUTRITION, 1992, 56 (03) :573-578
[9]   PHYTASE ACTIVITY IN THE HUMAN AND RAT SMALL-INTESTINE [J].
IQBAL, TH ;
LEWIS, KO ;
COOPER, BT .
GUT, 1994, 35 (09) :1233-1236
[10]  
IRVING GCJ, 1980, INOSITOL PHOSPHATES, P85