• 동아시아식생활학회지
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• 제16권4호
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• pp.421-428
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• 2006

This study assessed the effects of daily isoflavone intake on urinary excretion of deoxypyridinoline(DPD), Ca and Zn excretion as an index of bone resorption rates in 162 postmenopausal osteoporotic women. There were 87 participants in the osteoporosis group and 75 in the control group. The average age in the osteoporosis group was 62.97 years and that of the control group was 63.67 years. There were no significant differences between the two groups in height, weight and body mass index. The osteoporosis group consumed significantly lower amounts of soy foods compared to the control group(p<0.00l). Daily isoflavone intake was significantly different between the osteoporosis group(29.19 mg) and the control group(48.56 mg). The average urinary excretion of deoxypyridinoline in the osteoporosis and control groups were 5.71 nmol/mmol Cr and 5.15 nmol/mmol Cr, respectively and these values were significantly different(p<0.05). In addition, the subjects in the osteoporosis group and control group exhibited significant difference in urinary excretion of Ca(200.16 mg/day, 177.05 mg/day respectively) and Zn(333.32 $\mu$g/day, 303.68 $\mu$g/day respectively) at the levels of p<0.0l and p<0.05, respectively. There were no significant differences between the two groups in mineral intake. Thus, daily isoflavone intakes may contribute to decreases in the rates of urinary excretion of deoxypyridinoline, Ca and Zn in postmenopausal subjects.

• Journal of Nutrition and Health
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• 제38권2호
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• pp.89-95
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• 2005

This study was performed to investigate the effect of soy isoflavone on plasma nitrite concentration and the antioxidant enzyme activities of erythrocyte and the liver using adult male rats fed high fat diet. Seven-week old male Sprague Dawley rats were divided into three groups and fed high fat diet (15% beef tallow, 1 % cholesterol; control: IF0) or high fat diets containing isoflavone 80 ppm (IF80) or 320 ppm (IF320) for 10 weeks. Plasma nitrite concentration as a vasodilator, and antioxidant enzyme activities in erythrocytes and the liver were measured. Plasma nitrite concentration was increased by 45% and 35%, respectively, in IF80 and IF320 than in IF0 group. Erythrocyte catalase, glutathione peroxidase (GPx) and glutathione reductase (GR) activities increased by 31 %, 30% and 40% in IF320 compared to IF0 group. Especially, erythrocyte GR activity increased by 61 % in IF80 group. However, catalase activity in the liver was decreased in IF80 group. GPx and GR activities in the liver were not differ among groups. The results suggest that soy isoflavone have the protective effect against risk factors related with cardiovascular disease by improving vasodilator factor, nitrite, and antioxidant enzyme activities in blood. (Korean J Nutrition 38(2): 89～95, 2005)

• Journal of Nutrition and Health
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• 제38권3호
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• pp.203-210
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• 2005

Many young women suffer from premenstrual syndrome (PMS). The purpose of this study was to examine the effect of isoflavone on serum sex hormone and PMS during the luteal phase of the menstrual cycle. We investigated the incidence of PMS in 116 Korean female college students. The incidence of PMS was $19.8\%$. Among them, 9 PMS and 13 control were given 90 mg isoflavone per day during 2 menstrual cycles. The changes in anthropometric measurements, dietary intakes, serum parameters including sex hormones, and PMS symptoms were observed. Isoflavone supplementation did not affect anthropometric measurements. However, SBP and DBP were significantly decreased in control. Dietary intakes were not changed after supplementation of isoflavones. Serum SHBG was lower in PMS group than in control and significantly decreased in control with isoflavone supplementation. PMS symptoms such as backache, sweet, salty, and fatty food craving, coffee/tea drinking, and anxiety were significantly lessened. Based on these results, isoflavone supplementation may benefit young women by reducing some of PMS. Further studies of soy isoflavones effect on sex hormone and PMS may help to prepare for PMS management.

• Journal of Nutrition and Health
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• 제36권1호
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• pp.32-39
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• 2003

Phytoestrogens, especially soy-derived isoflavones, are receiving great scrutiny as a food supplement for preventing hormone dependent disease such as postmenopausal osteoporosis. Their beneficial effects are derived from aglycone form of isoflavones, such as daidzein, genistein or glycitein. In contrast to the common usage of soybean, black bean (Rhynchosia Molubilis : Yak-kong) has been used as a supplement for preventing postmenopausal osteoporosis in oriental medicine. To investigate the effects of the saliva, artificial stomach fluid, and digestive enzymes on the conversion of glycosidic isoflavone to aglycone form, soybean and black bean were extracted with 70% methanol and freeze-dried. The recovery yield of methanol extracts of black bean was 14.1% which was higher than that of soybean, 13.5%. In terms of total isoflavones, we routinely obtained larger amount of isoflavones from black bean than those from soybean. By incubating methanol extracts of soybean and black bean with IN HCI for 180 min, the proportions of aglycones relative to the total isoflavone were significantly increased (32.4% and 52.4%, respectively). In vitro conversion, digestive enzymes ($\beta$-glucosidase and $\alpha$-glucosidase) may hydrolyze glycosidic bond of isoflavone more effectively than saliva or artificial stomach fluid did. It seems to say that the activity of $\beta$-glucosidase was higher than those of $\alpha$-glucosidase. The rate of conversion of glucoside form to aglycone form in black bean and soybean was low in physiological condition (pH) tested, although the enzymatic hydrolysis of glucoside was active. These results demonstrated that the composition of aglycone in food may be the important factors in terms of the bioavailability of isoflavones. (Korean J Nutrition 36(1): 32-39, 2003)

• Journal of Nutrition and Health
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• 제39권3호
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• pp.236-243
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• 2006

A recent study reported that a diet rich in isoflavones is beneficial for bone formation in growing rats. It therefore seemed desirable to find out whether the beneficial effect of isoflavones in ovariectomized rats could also be reproduced with same amount of isoflavones which used for growing rats. To study the effect of isoflavones, an equal amount of isoflavones which used for growing rats, on bone mineral density and bone mineral content in ovariectmized rats were performed. Forty female Sprague-Dawley rats (body weight $210{\pm}5g$) were divided into two groups, ovariectomy and sham groups, which were each randomly divided into two subgroups that were fed casein and casein supplemented with isoflavones diets for 9 weeks after operation. All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin) in spine and femur. Serum alkaline phosphatase activity (ALP) and osteocalcin and urinary DPD crosslinks value were measured as markers of bone formation and resorption. The results of this study indicate that body weight gain and food intake were higher in ovariectomy groups than in sham groups regardless of diets. Serum Ca concentration was lower in ovariectomy groups than in SHAM groups. Serum ALP, osteocalcin, and crosslink value were increased in ovariectomy groups. Spine BMD/weight, femur BMD/weight, and femur BMC/weight of ovariectomy groups were significantly lower than SHAM groups after 9 weeks. However, isoflavones supplemented group in ovariectomy groups, serum ALP and osteocalcin concentrations, spine BMD/weight and spine BMC, femur BMD/weight and femur BMC/weight were significantly increased after 9 weeks. In conclusion, the beneficial effect of isoflavones on bone in ovareiectomized rats was shown on 9 weeks after feeding with an equal amount of isoflavones supplementation which used for growing rats.

• Journal of Nutrition and Health
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• 제38권1호
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• pp.40-47
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• 2005

This study was performed to determine the effect of three different concentrations of soy-isoflavones on calcium and phosphorus balance in either sham-operated or ovariectomized female rats. Seventy-two 16-week old Sprague-Dawley rats underwent sham operation or bilateral ovariectomy. They were provided diets containing different levels of soy iso-flavones for 6 weeks: 50 ppm (Jow isoflavone intake; LI) , 250 ppm (medium isoflavone intake; MI) and 500 ppm (high isoflavone intake; HI). The subsequent fecal and urinary excretions of calcium and phosphorus were then measured. In the sham-operated rats, body weight gains and food efficiency ratio of the MI and HI groups were significantly lower than the control group while food intake was not different. However, there was no significant difference in the ovariectomized rats. The fecal excretion of calcium was significantly lower in the LI, MI and HI groups than the control group in sham operated rats, and significantly lower in the HI group than the control group in ovariectomized rats. Also, apparent ab-sorption rate of calcium and phosphorus did not show any significant difference among groups. Urinary excretion of calcium and phosphorus was significantly lower in the HI group than the LI group in the sham-operated rats. Urinary excretion of calcium was significantly higher in the control ovariectomized rats than in the control sham-operated rats. Retention of calcium and phosphorus did not show any significant difference in both groups. From the above result, we see that isoflavone intake increases calcium retention through an increase in calcium absorption and also suppresses the increase of calcium excretion in urine in ovariectomy. Therefore, it is suggested that isoflavone intake is recommended for menopausal women who experience sharp bone loss due to the decrease in estrogen honnone.

• Journal of Nutrition and Health
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• 제36권5호
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• pp.476-482
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• 2003

We studied the effects of soy isoflavone supplements on bone metabolism marker (serum osteocalcin, urinary deoxypyridinoline) and urinary mineral excretion (urinary Ca, Mg, Zn) in 47 postmenopausal women. There were 24 participants in the treatment group and 23 in the control group. The treatment group consumed isoflavone extract capsules daily (which contained 90 mg of soy isoflavones) for 12 weeks. The study compared before and after isoflavone intake in the following areas: Physical examination, diet survey, bone metabolism marker and urinary mineral excretion. The average age of the treatment group was 64.6 years and that of the control group was 66.5 years. There were no significant differences between the two groups in terms of height, weight and body mass index. Both groups maintained a regular diet pattern in terms of their average daily nutrient intake. There were no significant differences between the treatment group (23.9 mg) and the control group (25.4 mg) in terms of daily isoflavone intake based on diet. The analysis of bone metabolism marker changes in the treatment group after 12 weeks of taking the isoflavone supplements demonstrated significant differences in the following: Serum osteocalcin (13.7 ng/mL in befor versus 6.8 ng/mL in after) and urinary deoxypyridinoline (5.9 nmol/mmol Cr in befor versus 4.5 nmol/mmol Cr in after). The subjects in the treatment group showed no significant difference in urinary Ca excretion. But the subjects showed a significant difference in urinary Mg (131.9 mg/day in befor versus 115.6 mg/day in after) and Zn (400.5 $\mu\textrm{g}$/day in befor versus 310.2 $\mu\textrm{g}$/day in after) excretion in the isoflavone treatment group at the levels of p<0.001, p<0.01, respectively. No changes were made in the intake of minerals. The composition of serum osteocalcin and urinary deoxypyridinoline, and indicators of bone metabolism, including the excretion Mg and Zn, significantly decreased. As a result, bone mineral loss was lessened. (Korean J Nutrition 36(5): 476~482, 2003)

• Journal of Nutrition and Health
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• 제39권4호
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• pp.338-346
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• 2006

The overall purpose of this study was to investigate the effects of level of isoflavones supplementation on bone metabolism in growing female rats. The effects of level of isoflavones supplementation on bone mineral density (BMD) and bone mineral content (BMC) were inspected in this study. Forty-five rats divided into three groups: Casein, $^1/{_2}IF$, IF. The serum and urine concentrations of calcium and phosphorus were determined. BMD and BMC were estimated by using PIXImus (GE Lunar Co, Wisconsin.) in spine and femur on 3, 6, 9 weeks after feeding. This study of results were as follows: The isoflavones supplementation level did not affect weight gain, mean food intake and food efficiency ratio. The serum concentration of calcium, phosphorus were not significantly different by different level of isoflavones supplementation. The urinary calcium and phosphorus excretion were not significantly different, too. Spine and femur BMD, BMC were not significantly increased by different level of isoflavones supplementation on 3 and 6 weeks after feeding. Spine BMD and spine BMC per weight, femur BMC per weight were significantly increased in the groups $^1/{_2}IF$ and IF at the ninth week after feeding, but there was no significant difference by different level of isoflavones supplementation. Spine BMD per weight and femur BMD per weight were significantly higher in the group of IF than in the group of Casein and $^1/{_2}IF$ at the ninth week after feeding. These results suggest that the group of IF with rich isoflavones supplementation was effective to the increase of BMD spine and femur in growing female rats, respectively.

• Journal of Nutrition and Health
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• 제39권8호
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• pp.801-807
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• 2006

To elucidate the effect of soy isoflavone supplementation on bone mineral density and antioxidant enzyme activity in 60 postmenopausal women residing in Iksan area were recruited. There were 31 participants in the treatment group and 29 in the control group. The treatment group consumed isoflavone extract capsules daily (which contained 90 mg of soy isoflavones) for 12 weeks. The study compared before and after isoflavone intake in the following areas. Physical examination, diet survey, bone mineral density (BMD) and antioxidant enzyme activity (superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and total antioxidant capacity (TA)). The average age of the treatment group was 64.6 years and that of the control group was 66.5 years. There were no significant differences between the two groups in terms of height, weight and body mass index. Both groups maintained a regular diet pattern in terms of their average daily nutrient intake. There were no significant differences between the treatment group (23.3 mg) and the control group (24.0 mg) in terms of daily isoflavone intake based on diet. Isoflavone supplementation of 12 weeks did not resulted in any significant changes in BMD or parameters of antioxidant enzyme activity, implying the necessity of more intensive intervention for a substantial change. In conclusion, this study revealed that antioxidant enzyme activity holds a significant relationship with the bone mineral density in postmenopausal women and further systematic research on dose and period of isoflavone supplementation is needed to clearify the positive effect of isoflavone on BMD and/or blood antioxidant capacity in postmenopausal women.

• Journal of Nutrition and Health
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• 제36권5호
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• pp.470-475
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• 2003

The purpose of this study was to investigate the effect of isoflavone supplementation using soymilk on bone mineral density in underweight college women aged 19-22 years with lower than average bone mass. The bone mineral density (BMD) of the lumbar spine and femoral neck of a number of underweight (BMI < 20) college women was measured. From this group, 33 subjects whose T-score value was below -1 were selected. Anthropometric measurements, dietary recall and BMD were measured before the study began and at the end of the 10th week. The 33 subjects were given 400 ml of soymilk containing 60 mg of isoflavones daily for 10 weeks. After 12 weeks at the end of 10 weeks treatment, the BMD of the subjects was reassessed. The average age of the subjects was 21.1 yrs. At the baseline, average height, weight, and BMI of the subjects were 161 cm, 49.1 kg, 18.8 kg/$m^2$, respectively. Mean daily intake of energy and protein was 1637.2 kcal and 61.2 g, respectively. Mean dietary isoflavone intake was 17.4 mg. Despite the 400 ml soymilk supplementation, there was no significant change in nutrient intake after the 10-week treatment. However, there were significant increases in lumbar spine and femoral neck BMD. After the study, the BMD of the subjects' spine and femoral neck was lower than that before the study. In conclusion, soymilk intake was associated with a significant increase in the BMD of the lumbar spine and femoral neck in underweight college women with lower than average bone mass. (Korean J Nutrition 36(5): 470~475, 2003)