复合微量营养素补充剂对北京市成人血和尿营养素水平的影响

目的 探讨复合微量营养素补充剂对健康成人体内营养素水平的影响。方法 选择北京市152名推荐食谱问卷得分低于12分的健康成年人作为研究对象,采用随机数字表法分为安慰剂组和补充剂组,每组76名。两组分别服用安慰剂和复合微量营养素补充剂。8周后检测受试者血浆及尿液中营养素浓度的变化情况。并于研究第56天同时给两组受试者服用复合微量营养素补充剂,观察服药前和服药后2h血浆营养素水平变化。结果 安慰剂组有3例失访,失访率为5.7％。服用复合微量营养素补充剂8周后,补充剂组的血浆α-生育酚[(18.23±0.82)比(14.55±0.73)μmol/L]、β-胡萝卜素[（4.28±0.29）比（2.38±0.24）μmol/L]、维生素C[(42.65±2.11)比(27.49±1.76)μmol/L]、B6[(323.51±15.88)比(69.43±10.47) nmol/L]和B12浓度[(1005.27±23.00)比(796.85±35.57) pmol/L],尿维生素B1[(899.24±70.73)比(174.42±13.38) μg/g·Cr]和B2水平[(3227.68±330.04)比(259.10±33.33)μg/g·Cr],及红细胞叶酸水平[(720.09±21.33)比(633.17±28.75) nmol/L]均明显高于安慰剂组（P均=0.0000）,血浆γ-生育酚浓度明显低于安慰剂组[(2.18±0.13)比(2.87 ±0.26) μmol/L,P=0.0001]。服用复合微量营养素补充剂2h后,补充剂组的血浆维生素C水平明显高于安慰剂组[(54.53±2.43)比(23.02±1.77)mol/L,P=0.0000]。结论 服用复合微量营养素补充剂可改变健康成人体内的营养素水平,但其意义有待进一步研究探讨。     

Effect of vitamin C administration on leukocyte vitamin C level and severity of bronchial asthma

Oxidative stress mediated by reactive oxygen species is known to contribute to the inflammatory process of bronchial asthma. Reactive oxygen species are released into the bronchial tree by activated inflammatory cells. In this study, we aimed to determine the effect of vitamin C administration on leukocyte vitamin C level as well as severity of asthma. In this double blind clinical trial study we evaluated 60 patients with chronic stable asthma. The patients were divided into two groups (A and B) including 30 patients in each group. Patients in these groups were matched according to their age, weight, height, gender, BMI and drug consumption. In addition to standard asthma treatment (according to stepwise therapy in 4th step of bronchial asthma) in which the patients were controlled appropriately, group A received 1000 mg vitamin C daily and group B received placebo. At the baseline and after one month treatment, non-fasting blood samples were drawn for laboratory evaluations. Asthmatic patient's clinical condition was evaluated through standard pulmonary function test (PFT). The mean (±SD) leukocyte vitamin C level in group A at the baseline and after one month treatment with 1000 mg/day vitamin C, were 0.0903 (±0.0787) μg/108 leukocytes and 0.1400 (±0.0953) μg/108 leukocytes respectively (P<0.05). The mean (±SD) leukocyte vitamin C level in group B at the baseline and after one month administration of placebo, were 0.0867 (±0.0629) μg/108 leukocytes and 0.0805(±0.0736) μg/108 leukocytes respectively. The leukocyte vitamin C level in group A was higher than those of group B after one month treatment with vitamin C and placebo and the difference was statistically significant (P<0.05). Comparing PFT (FEV1, FVC and FEV1/FVC) in group B during the study period showed a significant increase in FEV1 (P<0.05), while the other two parameters remained unchanged. In group A, who received 1000 mg/day vitamin C, none of the spirometry parameters changed after one month treatment, indicating no effect of vitamin C treatment in the spirometry parameters.     

豆类发酵食品中维生素B_(12)的分离与定量

植物性食物不含维生素B_(12),但我们曾发现发酵食品中可检出维生素B_(12)活性物质。为了进一步确定这类食品中具有生理作用的钴维生素含量,建立了维生素B_(12)生物自显谱面积定量法,其要点如次:豆类发酵食品提取液点于滤纸上,以仲丁醇—水—氢氧化铵—5％氰化钾(100:50:1:0.25)为扩展剂,下行扩展,24—72小时后取出干燥,然后置于含有E、Coli44110及2,3,5—三苯基四唑(鎓)化氯的营养琼脂培养基上,显谱后测量生长圈面积,计算样品中钴维生素含量。 用上述方法测定了两种豆类发酵食品,其钴维生素含量均值:每百克臭豆付乳中含0.97μg,酱豆付乳含0.4μg。与动物性食品相比,这两种豆类发酵食品可视为维生素B_(12)较好来源。     

Sources and determinants of vitamin D intake in Danish pregnant women

Vitamin D deficiency during pregnancy has been associated with the development of several adverse health outcomes, e.g., pre-eclampsia, gestational diabetes mellitus, preterm delivery, low birth weight, birth length, and bone mineral content. The aims of the present study were to estimate the intake and sources of vitamin D in Danish pregnant women and to examine potential determinants of vitamin D intake of the recommended level (10 μg per day). In 68,447 Danish pregnant women the mean ± SD for vitamin D intake was 9.23 ± 5.60 μg per day (diet: 3.56 ± 2.05 μg per day, supplements: 5.67 ± 5.20 μg per day). 67.6% of the women reported use of vitamin D supplements but only 36.9% reported use of vitamin D supplements of at least 10 μg. Supplements were the primary source of vitamin D for the two higher quartiles of total vitamin D intake, with diet being the primary source for the two lower quartiles. Determinants of sufficient total vitamin D intake were: high maternal age, nulliparity, non-smoking, and filling out of the Food Frequency Questionnaire (FFQ) during summer or fall. We propose that clinicians encourage vitamin D supplementation among pregnant women, with special focus on vulnerable groups such as the young, smokers and multiparous women, in order to improve maternal and fetal health both during and after pregnancy.     

蔬菜维生素B_1、维生素B_2保留因子的研究

目的通过比较不同蔬菜、不同烹调方法间维生素B1、维生素B2保留因子(RF)的差异,探讨影响蔬菜维生素B1、维生素B2保留因子的因素。方法选取了常见的12种蔬菜,以炒、炖、炸、蒸、焯、盐腌的方法进行烹调,分别记录烹调前后的重量,采用GB/T5009.84-2003荧光法、GB/T5009.85-2003荧光法分别测定烹调前后维生素B1、维生素B2含量,计算出相应的重量保留因子(保留率)和维生素B1、维生素B2保留因子(保留率)。结果鲜豆类蔬菜,维生素B1的保留率大多在66%~75%之间,维生素B2的保留率在85%~90%之间。焯不论对于根茎类还是叶菜类都会造成维生素B1的较大损失,损失率为50%。对于叶菜类,焯同样会造成维生素B2较大损失,RF的均值为50,明显低于炒青菜(P<0.05)。根茎类和茄果类蔬菜在炒的烹调方式下维生素B2的RF值在77~79之间。结论焯会造成较大的维生素B1、维生素B2损失,炒的维生素B1、维生素B2保留率较高;烹调方法、蔬菜的品种是影响维生素保留因子的重要因素。     

血清B族维生素含量与癫痫相关性分析

目的 探讨B族维生素（B1、B6、B12）与癫痫发生的相关性.方法 选取2013年1至10月新诊断的癫痫患儿（均未服用抗癫痫药物）与非癫痫患儿各50例,应用LK3000V维生素检测仪分别检测各组血清B族维生素（B1、B6、B12）浓度.结果 癫痫患儿血清中维生素B1和B12的浓度分别为（132.81 ±7.31） nmol/L和（221.41±26.09） pg/ml,与非癫痫患儿血清中维生素B1和B12浓度[（130.44±5.12） nmol/L和（197.87±19.36） pg/ml]相比,差异无统计学意义（P=0.095,P=0.077）.癫痫患儿血清中维生素B6的浓度为（44.61 ±2.49） μmol/L,显著低于非癫痫患儿的血清维生素B6浓度（64.63±5.71） μmol/L （P=0.031）.结论 血清维生素B1、B12含量与癫痫无相关性,而血清维生素B6含量低下可能增加癫痫发作的风险.     

左乙拉西坦联合维生素B6治疗难治性小儿癫痫的效果

目的 探讨丙戊酸钠与左乙拉西坦分别联合维生素B6治疗难治性小儿癫痫的临床价值。方法 选取2019年5月—2020年11月本院收治的78例难治性癫痫患儿,按随机数字表法分为对照组、观察组,各39例,对照组予以丙戊酸钠+维生素B6进行治疗,观察组予以左乙拉西坦+维生素B6进行治疗,比较2组总体疗效、认知功能及血清神经元特异性烯醇化酶(NSE)、中枢神经特异蛋白(S100β)、胶质纤维酸性蛋白(GFAP)水平等。结果 观察组治疗总有效率为87.18%,高于对照组的66.67%(χ²=4.622,P=0.032)。治疗后,观察组操作智商(PIQ)、言语智商(VIQ)、全智商(FIQ)评分分别为(95.16±8.53)分、(98.62±8.17)分、(97.02±8.48)分,均高于对照组的(89.41±9.16)分、(92.45±8.99)分、(90.63±9.54)分(t=2.869、3.172、3.126,P<0.01)。治疗后,观察组血清NSE、S100β、GFAP水平分别为(9.07±2.85)μg/L、(0.35±0.09)μg/L、(1.95±0.56)...     

Selected Vitamins and Essential Elements in Meat from Semi-Domesticated Reindeer (Rangifer tarandus tarandus L.) in Mid- and Northern Norway: Geographical Variations and Effect of Animal Population Density

Meat samples (n = 100) were collected from semi-domesticated reindeer originating from 10 grazing districts in Norway. We aimed at studying concentrations, correlations, geographical variations and the effect of animal population density on vitamins A, B3, B7, B12 and E, and calcium, iron, zinc, selenium, chromium and cobalt. Mean concentrations of vitamins A, B3, B7; B12 and E were <5 μg, 6.6 mg, <0.5 μg, 4.7 μg and 0.5 mg/100 g wet weight, respectively. Concentrations of calcium, iron, zinc, selenium, chromium and cobalt were 4.7 mg, 2.8 mg, 6.4 mg, 19.4 μg, 1.7 μg and 0.5 μg/100 g wet weight, respectively. Vitamin E and selenium were the nutrients that exhibited the largest geographical variations (p < 0.05), although no geographical gradient was observed for any of the studied nutrients. Age had a significant effect on zinc and selenium concentrations. Iron was significantly positive correlated with calcium (r = 0.3416, p < 0.01) and vitamin B12 with zinc (r = 0.35, p < 0.05). Reindeer from districts with low animal population density had significantly higher selenium concentration than those from districts with medium and high population densities (p < 0.01). Reindeer meat contained higher vitamin B12, iron, zinc and selenium concentrations when compared to Norwegian beef, lamb, mutton, pork and chicken meat.     

Lack of nutritional equivalence in the 'meats and alternatives' group of the Australian guide to healthy eating

Aim: To assess the effects of different amounts and choices within the meats and alternatives food group of the Australian Guide to Healthy Eating (AGHE) on the content of iron, zinc, vitamin B‐12 and long‐chain n‐3 polyunsaturated fatty acids. Methods: Two sets of diets ranging in energy level were modelled, with constant or varying numbers of serves from meats and alternatives. Exchanges within the meats group were then conducted and the diets analysed. The main outcome measures are changes in iron, zinc, vitamin B‐12 and long‐chain n‐3 polyunsaturated fatty acid content, relative to estimated average requirements (EAR) or adequate intake in diets based on the AGHE. Results: Diets with a single serve of food of animal origin provided substantially more iron, zinc, vitamin B‐12 and n‐3 fats than diets with a single serve of plant origin (e.g. 125–175% vs 63–111% EAR iron for women and 50–73% vs 29–48% EAR iron for pregnant women; 85–120% vs 57–63% EAR zinc for men and 101–157% vs 68–90% EAR zinc for pregnant women; 95–160% vs 75% EAR for vitamin B‐12; and 26–166% vs 0% EAR n‐3 for men). These differences were accentuated in diets with multiple serves from this food group. Conclusion: There is a marked lack of nutritional equivalence between the foods of animal and vegetable origin that comprise the meats and alternatives food group of the AGHE. If nutritional similarity is to determine food group composition, the placement of legumes, nuts and seeds in future food guides may need to be reviewed.     

Aspects of meat quality: trace elements and B vitamins in raw and cooked meats

The present study focuses on two aspects of meat quality: the concentration of trace elements (iron, zinc, copper) and B vitamins (thiamine, riboflavin, niacin) in meats having the highest consumption in Italy and in some meats recently introduced in the markets and on the influence of cooking processes on the retention of these micronutrients. A number of meat cuts were analysed: beef (sirloin, fillet, roast beef, topside, thick flank), veal (fillet), lamb (chop) horse (fillet), ostrich (fillet, sirloin, leg), pork (saddle, loin, chump chop), chicken (breast, leg-lower part, leg-thigh, wing), turkey (breast, leg-lower part, leg-thigh) and rabbit (whole). Results showed differences in both trace elements and B vitamins not only among meats of different species but also among cuts of the same species. Micronutrients content in horse and ostrich meats were in some cases of relevance compared to the most consumed meats. Cooking methods utilized in this study did not require water, which allowed a high retention of trace elements affecting mainly B vitamin concentration.     

Vitamin intake in Japanese women college students

The Standard Food Tables of Japanese Foods was newly revised in 2000, and contains information on all of the vitamins except biotin. Thus, we carried out a survey of vitamin intake in Japanese women who were university seniors majoring a dietitian course. The subjects (n = 33) consumed self-selected foods, and food intake was recorded by the weight method. We calculated the vitamin intake except for biotin from the food records using the Standard Food Tables of Japanese Foods. In terms of daily intake, vitamin A was 705+/-435 microg (mean+/-SD), vitamin D 6+/-8 microg, vitamin E 7.7+/-3.0 mg, vitamin K 191+/-156 microg, vitamin B1 0.7+/-0.3 mg (0.43+/-0.15 mg/1,000 kcal), vitamin B2 1.1+/-0.4 mg (0.65+/-0.18 mg/1,000 kcal), vitamin B6 0.9+/-0.4 mg (0.017+/-0.005 mg/g protein), vitamin B12 4.4+/-4.1 microg, niacin equivalent 23+/-7 mg (14.4+/-4.9 mg/1,000 kcal), pantothenic acid 4.6+/-1.4 mg, folic acid 267+/-115 microg, and vitamin C 73+/-38 mg. All of these averages were around the Japanese Recommended Dietary Allowance (RDA) for level "III (preferable)" of physical activity. Major vitamin A resources were vegetables; vitamin D resources, fish; vitamin E resources, fats and oils and vegetables; vitamin K resources, vegetables; vitamin B1 resources, cereals and animal meats; vitamin B2 resources, various foods; vitamin B6 resources, cereals, vegetables, fish, and animal meats; vitamin B12 resources, fish; niacin equivalent resources, fish, animal meats, and cereals; pantothenic acid resources, various foods; folic acid resources, vegetables; and vitamin C resources, vegetables and potatoes. From this survey, it was found that Japanese women college students consumed many kinds of food, and therefore, their vitamin nutrition was good as compared to the RDA values for level III of physical activity; however, their energy intake (1,622+/-377 kcal) was lower than the RDA for level III (2,050 kcal/d). Their strength of physical activity would be level I. Therefore, in consideration of their lifestyle, their energy intakes is considered adequate. In conclusion, a problem for student lifestyle is a shortage of food intake due to lack of exercise.     

维生素B_(12)与叶酸对辐射损伤的效应研究——一、尿中亚胺甲基谷氨酸排出量

选取刚断奶的雄性大鼠,饲以含有1％琥珀酰磺胺噻唑的、无维生素B_(12)和叶酸的饲料,并经口每日每鼠补给不同量维生素B_(12)和叶酸,以组氨酸负荷尿中亚胺甲基谷氨酸的排出量为主要指标,观察急性辐射损伤时维生素B_(12)与叶酸的营养效应。其主要结果如下: 1.当大鼠仅摄食实验饲料,3—5周内就出现了明显的缺乏维生素B_(12)与叶酸的症状,如食欲锐减,体重增长率减慢继而下降,尾血白细胞总数下降,24小时尿中亚胺甲基谷氨酸排出量明显高于正常(由正常的0.55mg增至14～17mg)等。摄食维生素B_(12)0.02μg与叶酸0.5μg组的上述症状较未补充者轻。摄食维生素B_(12)0.1μg与叶酸2.5μg组的食欲、体重增长率等已较正常,但组氨酸负荷尿中亚胺甲基谷氨酸排出量仍高于正常(由正常0.55mg增至3.41mg)。摄食维生素B_(12)0.3μg与叶酸7.5μg组在上述各项指标上均显示与正常无差别。) 2.上述经口补充不同量维生素B_(12)与叶酸的各组动物,经700rad照射(实验饲养36天时后,除摄食维生素B_(112)0.3μg与叶酸7.5μg组外,其余两组的组氨酸负荷尿中亚胺甲其谷氨酸排出量均比照射前更为增加,(分别由12.36增至23～28mg、3.41增至6～9mg/24h),显示照后此两种维生素的缺乏或不足程度加重。 3.摄食维生素B_(12)0.02μg与叶酸0.5μg的大鼠?     

Response to vitamin D supplementation during Antarctic winter is related to BMI, and supplementation can mitigate Epstein-Barr Virus Reactivation

Maintaining vitamin D status without sunlight exposure is difficult without supplementation. This study was designed to better understand interrelationships between periodic vitamin D supplementation and immune function in Antarctic workers. The effect of 2 oral dosing regimens of vitamin D supplementation on vitamin D status and markers of immune function was evaluated in people in Antarctica with no UV light exposure for 6 mo. Participants were given a 2000-IU (50 μg) daily (n = 15) or 10,000-IU (250 μg) weekly (n = 14) vitamin D supplement for 6 mo during a winter in Antarctica. Biological samples were collected at baseline and at 3 and 6 mo. Vitamin D intake, markers of vitamin D and bone metabolism, and latent virus reactivation were determined. After 6 mo, the serum 25-hydroxyvitamin D concentration (mean ± SD) increased from 56 ± 17 to 79 ± 16 nmol/L and from 52 ± 10 to 69 ± 9 nmol/L in the 2000-IU/d and 10,000-IU/wk groups, respectively (main effect over time, P < 0.001). Participants with a greater BMI (participant BMI range = 19–43 g/m2) had a smaller increase in 25-hydroxyvitamin D after 6-mo supplementation (P < 0.05). Participants with high serum cortisol and higher serum 25-hydroxyvitamin D were less likely to shed Epstein-Barr virus in saliva (P < 0.05). The doses given raised vitamin D status in participants not exposed to sunlight for 6 mo, and the efficacy was influenced by baseline vitamin D status and BMI. The data also provide evidence that vitamin D, interacting with stress, can reduce risk of latent virus reactivation during the winter in Antarctica.     

Effects of Long-term Vitamin K (Phylloquinone) Intake on Retina Aging

Abstract

Emerging evidence suggests neuroprotective functions of vitamin K and/or vitamin K-dependent proteins. We investigated the effect of dietary vitamin K on retina aging (thinning). Female Sprague-Dawley rats were maintained from weaning on low (80 μg kg<PRE>-1</PRE> diet), adequate (500 μg kg<PRE>-1</PRE> diet) or high (2000 μg kg<PRE>-1</PRE> diet) levels of vitamin K1 (phylloquinone). Relative concentrations of brain vitamin K associated with these diets were 1: 3.3: 25 (K1) and 1: 2.7: 9.0 (menaquinone-4). Histomorphometry of old (21 month) rats revealed positive associations between vitamin K and thickness of retina layers, especially in the equatorial/peripheral retina. No association of diet and retina thickness was detected among young (6 month) animals. The sparing effect of vitamin K in the retina was most evident in the inner plexiform layer and in the photoreceptor inner and outer segments. Surprisingly, we observed no effect of vitamin K on the age-dependent loss of photoreceptor cells, interneurons or ganglion cells. These data suggest a role for vitamin K in maintaining the aging retina and suggest that the sparing effect of vitamin K does not reflect the survival-promoting (anti-apoptotic) activities of vitamin K-dependent proteins.     

Feeding dried purple laver (nori) to vitamin B12-deficient rats significantly improves vitamin B12 status.

To clarify the bioavailability of vitamin B12 in lyophylized purple laver (nori; Porphyra yezoensis), total vitamin B12 and vitamin B12 analogue contents in the laver were determined, and the effects of feeding the laver to vitamin B12-deficient rats were investigated. The amount of total vitamin B12 in the dried purple laver was estimated to be 54.5 and 58.6 (se 5.3 and 7.5 respectively) microg/100 g dry weight by Lactobacillus bioassay and chemiluminescent assay with hog intrinsic factor respectively. The purple laver contained five types of biologically active vitamin B12 compounds (cyano-, hydroxo-, sulfito-, adenosyl- and methylcobalamin), in which the vitamin B12 coezymes (adenosyl- and methylcobalamin) comprised about 60 % of the total vitamin B12. When 9-week-old vitamin B12-deficient rats, which excreted substantial amounts of methylmalonic acid (71.7(se 20.2) micromol/d) in urine, were fed the diet supplemented with dried purple laver (10 microg/kg diet) for 20 d, urinary methylmalonic acid excretion (as an index of vitamin B12 deficiency) became undetectable and hepatic vitamin B12 (especially adenosylcobalamin) levels were significantly increased. These results indicate that vitamin B12 in dried purple laver is bioavailable to rats.     

Effect of end-user preparation methods on vitamin content of fortified humanitarian food-aid commodities

The effect of cooking on vitamin stability in common fortified food-aid commodities was evaluated: corn–soy blend (CSB), cornmeal (CM), soy-fortified bulgur (SFB), and vegetable oil (VO). Thin CSB porridge, thick CM and SFB porridges, and dumplings fried in VO were prepared using average preparation parameters determined from the data collected in the field. Vitamin levels in pre- and post-cook samples were tested. In CSB thin porridge, vitamins C and E showed cooking losses of 53% and 18%, respectively; thiamin, folic acid, riboflavin, pantothenic acid, pyridoxine HCl, vitamin A, and vitamin B12 showed no significant losses. In CM thick porridge, thiamin, folic acid, riboflavin, and vitamin A showed no significant changes during cooking. In SFB, vitamin A was reduced by 33%, while thiamin, folic acid, and riboflavin showed no significant changes during cooking. In VO that was used to prepare dumplings, vitamin A losses of 6% occurred after one frying cycle. Vitamin A content of the dumplings, however, increased significantly during frying. With the exception of vitamins C and E in CSB and vitamin A in SFB and VO, typical cooking had little effect on vitamin stability.     

1982年与2012年中国6~17岁学龄儿童膳食维生素A的摄入比较

目的  了解中国6~17岁学龄儿童(以下简称学龄儿童)膳食维生素A、视黄醇和胡萝卜素摄入水平,为促进儿童营养改善和健康成长提供基础数据。方法  通过分析1982年全国营养调查和2012年中国居民营养与健康状况监测中的膳食调查数据,计算学龄儿童每人每天各种食物及调味品摄入量。根据1982年与2012年的食物成分表,分别计算动物性食物来源的视黄醇和植物性食物来源的胡萝卜素摄入量,并将二者折合计算维生素A总量,与维生素A的推荐摄入量(recommended nutrient intake, RNI)进行比较。结果  中国学龄儿童膳食维生素A摄入总量(μg RAE)从1982年的(333.3±15.9)μg RAE下降到2012年的(215.3±9.5)μg RAE(F=61.95, P < 0.001);其中,视黄醇摄入量从(28.4 ±2.0)μg增加到(107.6±4.8) μg(F=225.36, P < 0.001),胡萝卜素摄入量从(3 673.9±217.3)μg下降到(1 297.4±82.0)μg(F=214.98, P < 0.001)。1982年儿童膳食维生素A摄入总量为农村高于城市(F=5.28, P=0.022),2012年则为城市高于农村(F=14.85, P < 0.001)。2012年仅有四分之一的儿童膳食维生素A摄入量达到80%RNI以上。结论  1982—2012年中国学龄儿童膳食维生素A摄入水平整体有所下降,动物性食物贡献率有所增加,植物性食物贡献率大幅度降低。建议加强膳食指导,丰富农村儿童食物供应的种类,改善儿童的维生素A营养状况。     

Effect of resistant starch on the cooking quality of yam (Dioscorea spp.) and cassava (Manihot esculenta) based paste products

Total starch (TS) and resistant starch (RS) contents in pasty edible product of mealy and hard cooking tubers of three yam varieties and four cassava varieties were determined to evaluate their contribution in their cooking quality. TS and RS contents appeared as the main components in determining yam cooking quality. Mealy cooking yam varieties were characterized by a significant higher TS content (75.2 ± 7.7 g/100 g d.m.) and lower RS content (13.8 ± 3.4 g/100 g d.m.) than hard cooking yam varieties, which, in contrast, contained less TS (61.7 ± 12.1 g/100 g d.m.) and particularly high RS (21.8 ± 9.9 g/100 g d.m.), possibly as a consequence of the prevalence of large granules (35–40 μm) observed by light microscope. Conversely, TS and RS contents appeared not determinant on the cooking quality of cassava. Moreover, higher amylose contents were associated with substantially elevated percentages of RS in yam and cassava, and high RS content in samples modulates their pasting properties by reducing the peak viscosity and the breakdown and requiring higher temperature and longer time to the peak.     

高温作业钢铁工人水溶性维生素摄入和消耗及体内水平调查

目的了解钢铁工人在目前高温作业环境下通过汗、尿消耗的水溶性维生素B_1、B_2、C及其膳食摄入和体内水平,为制定营养干预方案提供依据。方法于2014年6—7月选取高温作业钢铁工人226人及同一车间非高温作业工人39人,进行膳食调查和汗、尿收集及维生素测定,用体重差法估计出汗量,同时测定工作场所湿球黑球温度指数(wet bulb globe temperature index,WBGT指数)。结果高温作业钢铁工人维生素B_1、B_2、C平均摄入量分别为(2.2±0.5)、(1.2±0.3)、(102.0±23.3)mg/d;不同作业温度的工人每日摄入量均无明显差异(P0.05)。工人在WBGT为30~43℃高温环境作业时的汗中维生素B_1、B_2、C排出量分别为(0.24±0.08)、(0.20±0.08)、(16.30±7.78)mg/d,分别占汗、尿中排出总量的73.8%,67.9%和68.3%。同等中体力劳动高温工人的汗中维生素B_1、B_2、C排出量均高于非高温工人,差异有统计学意义(P0.01)。重体力劳动强度下不同作业温度的高温工人汗中维生素B_1、B_2、C排出量均随温度升高而增加(P0.05);尿中3种维生素排出量均随温度升高而降低。高温作业工人维生素B_1、B_2、C与尿肌酐的平均比值分别为121.8±39.7、99.4±43.8、6.1±2.3。维生素B_1、B_2、C体内缺乏人数分别占总人数的10.6%,31.9%,95.1%。中体力劳动强度的高温作业工人维生素C体内缺乏率高于非高温作业工人,差异有统计学意义(P0.05)。结论钢铁工人在高温作业环境中的维生素B_1、B_2、C消耗量较多,维生素摄入量均低于高温作业建议量。建议按摄入量与高温作业人员建议量的差值并考虑体内缺乏程度来制定工间液体补充方案。     

不同烹调油样品中邻苯二甲酸二丁酯与邻苯二甲酸二（2-乙基己基）酯的分析

[目的]了解不同烹调油样品中邻苯二甲酸二丁酯（di-n—butyl phthalate,DBP）与邻苯二甲酸二（2-乙基己基）酯[di（2-ethylhexyl）phthalate,DEHP]的污染情况。[方法]采用气相色谱-质谱联用仪的选择离子检测（SIR）方式,测定取自居民家中未加热食用油、烹调剩油和厨房抽油烟机内油盒中的烹调油烟冷凝物,食堂中未加热食用油、烹调剩油和烹调油烟冷凝物;小摊贩所用的未加热食用油及其锅内剩油;快餐店未加热过的固体起酥油及烹调剩油等样品中DBP与DEHP的含量。[结果]9户居民家庭厨房和食堂不同烹调油样品中DBP和DEHP均为阳性,且烹调油烟冷凝物中的含量明显高于未加热食用油和烹调剩油中的含量;DBP和DEHP含量：前者分别为2．29～597．01μg／g和38．96～4774．72μg／g;后者分别为3．22～42．81μg／g和15．61～112．64μg／g。小摊贩和快餐店不同烹调油样品中,仅1例炸面食剩油检出DBP和DEHP。[结论]大部分烹调油样品被DBP、DEHP污染,且烹调油烟冷凝物中的含量大大增加。