• Journal of Nutrition and Health
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• v.26 no.2
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• pp.145-155
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• 1993

A factorial experiment was conducted to determine the influence of phytate(0 or 10g/kg diet) and calcium (Ca)(3 or 10g/kg diet) intakes on Ca, P and Zn metabolism by growing female rats. Food intake and weight were similar for the all groups, however, phytate ingestion for six weeks depressed femur growth. The low Ca plus phytate group showed the lowest Ca content of total femur and this was related to a significant decrease of Ca retention. Phytate intake depressed zinc(Zn) absorption in the first metabolic collection. This inhibitory effect of phytate on Zn absorption was improved in the low Ca plus phytate group after several weeks. Impared Zn absorption however remained in the high Ca plus phytate group which was reflected in the lowest Zn content of femur, phytate intake with high Ca also depressed phosphorous(P) absorption and serum and urinary P. These adverse effects of phytate on Zn and P absorption when the dietary Ca was high could explain reduced femur weight despite the highest concentration of femur Ca(mg/g ash) in this group. Results suggest that phytate can adversely affect not only Ca metabolism but Zn and P utilization. Thus, for the normal bone growth when phytate intake is high, the ingesion of Ca, P, Zn and other minerals should be enhanced.

• Preventive Nutrition and Food Science
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• v.11 no.1
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• pp.67-72
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• 2006

To determine the amount of phytate in rice grains from various cultivars, two methods were employed and compared in respect of the accuracy and conveniency. Phytate in rice samples was extracted with HCl, and then the extracts were subjected to an anion-exchange column. Finally, the phytate in eluate was quantitated using two methods: one method is based on the complex formation between ferric ion and sulfosalicylic acid in the presence of phytate, and the other is the prior acid digestion of phytate sample, followed by the colorimetric determination of liberated phosphorus. Although two methods showed similar values of phytate in rice samples, the former method is simpler and more precise than the latter. Moreover, the former is more reliable for the samples with lower phytate levels. Especially, the dilution condition of rice sample before anion exchange column separation was important for the recovery of phytate in rice samples. Based on the former method, the amount of phytate in rice of various cultivars was estimated to range from 7.3 mg/g to 12.4 mg/g rice. This method would be useful for the determination of phytate in crop samples with a lower level of phytate, one of anti-nutrients in some agricultural plants.

• Journal of Nutrition and Health
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• v.28 no.10
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• pp.986-994
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• 1995

This study was to examine the effect of phytate on the protein digestibility and calcium, iron and zinc availability in phytase treated soymilks digested with pepsin and pepsin-pancreatin in vitro. Also, the bending between phytate and protein in soymilks was investigated by means of SDS-PAGE. The content of phytate in soymilk was reduced by phytase treatment. As the content of phytate decreased, the protein digestibility increased in soymilk treated with the digest enzymes in vitro. The reduction of phytate content in soymilk improved the availability of all calcium, iron and zinc. Although the availability of calcium increased, the amount of change was small. The phytate reduction increased most the availability of iron. A number of bands of high molecular weight protein in soymilk disappleared in SDS-PAGE by lowering the phytate content with phytase treatement on soymilk.

• Microbiology and Biotechnology Letters
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• v.29 no.4
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• pp.195-200
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• 2001

Among lactic acid bacteria isolated from young animal feces, a bacterium having high phytate degradation ability, identified as L. paracasei subsp. paracasei, was selected. When inoculated into soybean meal, wheat bran and rice bran, the bacterium showed phosphate group of phytate (phytate-P) degrad- ability of 27.07% for soybean meal and 12.18% for wheat bran. However, degradation of phytate-P was not observed for rice bran L. paracasei subsp, paracasei had good acid and bile juice tolerance, having 9.70, 9.66 and 8.80 (log CFU/ml) for control, acid and bile juice treatment. Feed efficiency increased from 3.71 to 3.21 with addi- tion of the bacterium at 0.4% (w/w) level in swine fattener\`s diets.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.231-237
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• 2000

A Comparative study was performed among five Korean wheat(Greu, Eunpa, Tapdong, Allgreu, Woori) and three imported wheat(Dark Northern Spring, Austrian Standard Wheat, Western White) to investigate the characteristics of minerals and phytate from Korean wheat varieties. Ash contents of kernel was higher in Korean wheat than in imported wheat and related to ash contents and darkness of flour. More contents of Fe, P, and Mg from Korean wheat grains and Fe from Korean wheat flours were observed in comparison to imported wheat varieties. Fe concentration in Korean flour show high, indicating Fe was distributed at endosperm layer of kernels and not eliminated with milling. In addition, phytate affecting availability of minerals was determined from kernels and flours. Even though Korean wheat kernels had more phytate than that of imported wheat kernels, it is believed that most of phytate was removed with milling and there was no major difference between Korean and imported wheat flours. We also observed that the content of phosphate closely parallels the content of phytate from both the flours and kernels.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.321-326
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• 1989

Nitrogen and phytate solubility of perilla seed flour were influenced by the following factors: pH, centrifugal force, temperature and the presence of salt. The nitrogen solubility of perilla seed flour was minimum$(17.1{\sim}18.0%)$ at the pH range of $(4.0{\sim}5.0)$ and maximum(92.3%) at pH 11.0, while phytate solubility was the highest(48.5%) at pH 4.8 and lowest(8.3%) at pH 11.0. The phytic acid content in the extract decreased with an increase in centrifugal force. However, the nitrogen content was not affected by centrifugal force. The solubility of nitrogen and phytate gradually increased as the temperature was increased from $5^{\circ}C$ to $60^{\circ}C$ The addition of calcium$(0{\sim}50mM)$ at pH 5.0 decreased the phytate solubility, but increased nitrogen solubility. The solubility of nitrogen and phytate of perilla seed protein isolate was gradually increased as pH raised further. The protein and phytate contents of the perilla seed protein isolate were 1.1 and 89.6%, respectively, compared to 5.0 and 60.1% for perilla seed flour.

• Nutrition Research and Practice
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• v.1 no.4
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• pp.356-362
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• 2007

For the assessment of representative and longitudinal Zn nutriture in South Koreans, Zn, phytate and Ca intakes were determined using four consecutive years of food consumption data taken from Korean National Nutrition Survey Report (KNNSR) every 10 years during 1969-1998. The nutrient intake data are presented for large city and rural areas. Zn intake of South Koreans in both large city and rural areas was low during 1969-1988 having values between 4.5-5.6 mg/d, after then increased to 7.4 (91% Estimated Average Requirements for Koreans, EAR = 8.1 mg/d) and 6.7 mg/d (74% EAR) in 1998 in large city and rural areas, respectively. In 1968, Zn intake was unexpectedly higher in rural areas due to higher grain consumption, but since then until 1988 Zn intake was decreased and increased back in 1998. Food sources for Zn have shifted from plants to a variety of animal products. Phytate intake of South Koreans during 1969-1978 was high mainly due to the consumption of grains and soy products which are major phytate sources, but decreased in 1998. The molar ratios of phytate:Zn and millimmolar ratio of phytate${\times}$Ca:Zn were decreased due to the decreased phytate intake in South Koreans, which implies higher zinc bioavailability. The study results suggest that Zn nutriture has improved by increased dietary Zn intakes and the decreased molar ratio of phytate:Zn in South Koreans in both large city and rural areas.

• Nutritional Sciences
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• v.7 no.2
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• pp.83-87
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• 2004

To investigate the effects of dietary phytate reduction and zinc supplementation on biochemical iron parameters in elderly Korean women consuming inadequate iron, fifteen healthy women aged 64-75 years were recruited for a feeding study. A high-phytate diet (27.8 phytate:zinc molar ratio) was provided for 9 days, followed by a nine-day low-phytate diet(12.3) and a subsequent 28-day period of unregulated meals with zinc supplementation (22 mg/d as zinc gluconate). Serum iron increased significantly with the low-phytate diet (130.4 $\mu g$/L) but returned to the level observed during the high-phytate diet (113.0 $\mu g$ /L) period when subjects were taking zinc supplements (105.8 $\mu g$ /L). However, serum ferritin in the subjects decreased significantly with the low-phytate diet (73.8 $\mu g$ /L) as well as with zinc supplementation (57.2 $\mu g$ /L), compared to levels following consumption of the high-phytate diet (89.6 $\mu g$ /L). Transferrin receptor and transferrin saturation were unchanged with the treatments. In summary, zinc supplementation might result in deteriorated iron status in elderly Korean women who consume inadequate iron, while there was no significant effect from reducing dietary phytate.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.212-218
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• 1986

Proteins in Korean rapeseeds, as in many other plantseeds, are usually bound to phytate molecules. These phytate-bound proteins are of little value as foodstuffs because of their poor solubility in digestive systems. Therefore it is necessary to remove phytates from proteins in order to convert these proteins io a useful foodstuff. In the work, an efficient procedure for removal of phytates from defatted Korean rapeseed was found. The influence of pH on the solubility of protein and phytate of rapeseed flour showed that the former was the lowest at pH 5.0 and began to increase as pH further raised. Meanwhile, the latter was the highest at pH 6.0, however, it was decreased abruptly at alkaline pH, especially to content of 1.3% at pH 11.5. The solubility cf protein was relatively high in NaCl aqueous solution at $pH\;6.0{\sim}8.0$, and did not male any noticeable difference depending on NaCl concentration. On the other hand, the solubility of phytate was high at pH of below 6.0 showing an abrupt decrease at pH of above 6.0. The solubility of protein in $CaCl_2$ aqueous solution was highest at $pH\;6.0{\sim}8.0$, however, there was no significant change at the whole range of tested pH of the solution. A maximum solubility of phytate was shown at $pH\;3.0{\sim}4.0$. And it was decreased abruptly at a higher pH of the above range and also decreased at a lower pH with higher $CaCl_2$ concentration. The solubility of phytate in $Na_2SO_3$ aqueous solution was highest at $pH\;5.0{\sim}8.0$. As the concentration goes up the maximum value of solubility was found to move to higher pHs. Depending on the concentration of $Na_2SO_3$, the decreasing pattern was changed in an alkaline solution. The solubility of phytate in the solution containing low concentration of $Ca^{2+}$ ion was low in all treatments at pH of above 7.0 and showed the maximum value at low pH as $Ca^{2+}$ ion concentration increases. The solubility of protein at pH 11.5 showed the highest value in $1mM\;Ca^{2+}$ ion solution.

• International Journal of Human Ecology
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• v.4 no.1
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• pp.35-44
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• 2003

This study investigated the effects of dietary phyate reduction on the apparent absorption and biochemical parameters of iron status in young Korean women. Fourteen healthy, young women consumed low and high phytate diets for ten days of each experimental period. Duplicate diet samples, a fasting blood sample on day 9, and complete fecal samples for five consecutive days starting from day 5 of each diet period were collected. The iron content of diet and fecal samples were analyzed to calculate apparent absorption. Serum samples were analyzed for iron, ferritin, transferrin receptor and TIBC; transferrin saturation was also calculated. The apparent absorption of iron tended to increase in the low phytate period (32.51%) compared to the high phytate period (17.91%), but the difference was not significant (p=0.06). Serum ferritin decreased and serum transferrin receptor increased significantly during the low phytate diet although the mean values were within the normal range. Serum iron and transferrin saturation did not change significantly. In conclusion, the results indicated that reducing dietary phytate for ten days negatively affected iron nutritional parameters, but it moderately and positively affected apparent iron absorption in young Korean women. Further research on the long-term effects of a low phytate diet with an adequate iron content for vows Korean women is necessary.