大豆致甲状腺肿素去除的研究

大豆具有很高的营养价值 ,但大豆中存在的抗营养因子阻碍机体对某些营养成分的消化吸收利用。文章主要研究大豆中的致甲状腺肿素的去除方法。试验表明 :致甲状腺肿素可用 90℃ ,1 5min或 1 0 0℃ ,1 0min或 1 1 0℃ ,5min干热处理 ,灭活大豆中的硫代葡萄糖苷酶 (俗称内源性芥子酶 ) ,使之不能酶解硫代葡萄糖苷 ,也就不产生致甲状腺肿素 ,其残存的硫代葡萄糖苷率可达 98%。

去除大豆中致甲状腺肿素、凝血素和胰蛋白酶抑制剂的研究

为去除大豆中致甲状腺肿素、凝血素、胰蛋白酶抑制剂三种抗营养因子,本文考察了干热、温热、浸泡发芽方法（内源性酶法）对三种因子灭活或去除效果的影响。结果表明:于热处理对大豆致甲状腺肿素的去除,温热处理对大豆凝血素、蛋白酶抑制剂的去除有显著效果,大豆发芽结合热处理能略微提高去除大豆凝血素、蛋白酶抑制剂的效果。因此总结出先90℃干热处理15min以上,后125℃湿热处理10min以上的简便且节能的大豆前处理工艺,上述三种抗营养因子去除率均达95％以上。

实验性甲状腺肿甲状腺过氧化物酶活性的改变

分别测定低碘，致甲肿物质（ＭＭＩ）和高碘三种原因引起甲状腺肿动物的甲状腺过氧化物酶ＴＰＯ活性。结果显示低碘组和ＭＭＩ组ＴＰＯ活住显著高于对照组；高碘组ＴＰＯ活性明显降低．加喂高酪蛋白的实验组，低碘组和ＭＭＩ组Ｔｔｏ活性显著下降；而高碘组ＴＰＯ活性明显升高．结果提示高酪蛋白对甲状腺肿动物的ＴＰＯ活性有影响．

Morphological and functional alterations of female reproduction after regular exposure of bamboo shoots of North East India

Objective:To evaluate the effect of daily consumption of bamboo shoots (BS) on the morphological features and functional status of the female reproductive system in adult with respect to thyroid.Methods: Adult female rats were divided into control and experimental groups of six each. Control group was given normal diet while experimental group was fed BS by 1/3rd replacement of 180 g of their foodi.e.60 g of BS containing 35 g of goitrogens of cyanogenic origin such that each rat likely consumed 6 mg/100 g of body weight per day for a period of 45 d. Morphological features like changes in body weight and organ weight were noted. Key steroidogenic enzyme levels viz?53β hydroxysteroid dehydrogenase (HSD) and 17β HSD along with serum estradiol, estriol and progesterone levels were measured. Estrous cyclicity of the animals monitored regularly followed by histological analysis of thyroid, ovary and uterus at the end of experimentation.Results:Increase in body weight, thyroid gland weight and thyroid stimulating hormone, decrease in serum triiodothyronine and thyroxine, a decrease in ovarian as well as uterine weight and the activity of steroidogenic enzymes?53β HSD andβ17β HSD along with diminished serum estradiol, estriol and progesterone levels were noted;while histological plates showed prominent degenerative changes in both the ovary and uterus. Estrous cyclicity of the treated animals were irregular and almost stopped at diestrous stage of the cycle in the latter stage of the treatment as compared to control.Conclusions: Overall results indicates that BS rich in cyanogenic constituents induces biochemical hypothyroidism in the experimental animals that acts in corroboration to cause morphological and functional alteration of reproductive organs indicating its likely impact in fertility on continued use.

饲料中的致甲状腺肿物质

综述了饲料中常见的致甲状腺肿物质的种类及其来源、致甲状腺肿物质的抗甲状腺作用及其机理。

Thyroid function profile, and its association to consumption of cassava and <i>Moringa stenopetala</i>in pregnant women

Background: Pregnancy is associated with the change in thyroid function. Thyroid function is also affected by goitrogenic substances in some plant foods, like cassava. Aim: This study aims to assess thyroid function status and its association to consumption of foods containing goitrogenic substances. Methods: A cross sectional study was done on a total of 65 pregnant women attending Sawla Health Center, South Ethiopia. Serum samples were collected and analyzed for TSH, total T4 and total T3 by using ELISA kit. Data on consumption of foods containing were obtained from food frequency questionnaire. Results: The median TSH of the first, second and third trimesters, respectively are 2.57, 1.86 and 2.42 mIU/L, which are within the reference interval (0.30-6.20 mIU/L) of the test kit. The median total T4 values (9.8, 10.0 and 10.3 μg/dl in the first, second and third trimesters, respectively) were also within the reference interval (4.8-11.6 μg/dl) of the test kits. The median total T3 in the first (2.60 ng/ml) and third (2.35 ng/ml) trimesters were elevated, but it was within the reference interval (0.69-2.02 ng/ml) in the second trimester (1.92 ng/ml). Though statistically non-significant median TSH was increased in women grouped as cassava consumers and M. stenopetala consumers while median total T4 values were decreased in these groups. Conclusion: The study subjects have normal thyroid function as the median values of TSH and total T4 were within the reference interval of the test kit. Frequent consumption of cassava and Moringa stenopetala may affect thyroid function.

Regulatory Implications of Cumulative Risk for Perchlorate as an Iodide Uptake Inhibitor

This research applies aggregate and cumulative risk assessment considerations to intakes of compounds acting through the sodium-iodide symporter mechanism to produce iodide uptake inhibition into the thyroid. Four approaches to setting regulatory limits considered here based on NOELs/LOELs yield the following estimates of the safe levels of perchlorate in water (when perchlorate in water is the sole intake) or total goitrogens (PEC) acting through the same mechanism: 1) Approach 1: 18 μg/L;2) Approach 2: 400 μg/L (50% required inhibition) or 38 μg/L (5% required inhibition);3) Approach 3: 338 μg/L (without serum half-life correction) or 573 μg/L (with serum half-life correction);4) Approach 4: 737 μg/L (without serum half-life correction) or 973 μg/L (with serum half-life correction) for 50% required inhibition;375 μg/L (without half-life) or 735 μg/L (with half-life) for 5% required inhibition. Where water is not the sole route of exposure and perchlorate is not the sole goitrogen acting through the sodium-iodide symporter mechanism, the results of Approaches 3 and 4 can be applied to mixtures of compounds that produce these values as PECs. Results of the analysis suggest that compound-by-compound regulatory limits may be better dealt with through a change to risk-based management strategies that are built around the concept of focusing limited regulatory resources on the main contributors to risks induced by the mechanism considered here.

去除大豆致甲状腺肿素的研究

大豆具有很高的营养价值,但大豆中存在的抗营养因子阻碍机体对某些营养成分的消化吸收利用。本文主要研究大豆中的致甲状腺肿素的去除方法。试验表明:致甲状腺肿素可用90℃,15分钟或100℃、,10分钟或110℃,5分钟干热处理,灭活大豆中的硫代葡萄糖苷酶(俗称内源性芥子酶),使之不能酶解硫代葡萄糖苷,也就不产生致甲状腺肿素,其残存的硫代葡萄糖苷率可达98％。