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1.
为准确测定出油菜中维生素C的含量,在国标基础上,建立了一种高效、准确测定新鲜油菜维生素C含量 的方法。结果表明:维生素C在测定范围内峰面积与标准液浓度线性关系良好,相关系数为0.9999。油菜维生素C 含量测定的回收率为97.97%~101.40%,相对标准偏差RSD仅为1.84%,说明用该方法重现性良好,具有快速准确、 稳定可靠等特点。贮藏温度越低,维生素C降解的速度越慢,用液氮贮藏样品更有利于维生素C的保存和精准鉴 定;利用液氮冷冻并研磨样品更有利于样品中维生素C的提取,测得油菜中维生素C含量与仅均质化处理相比平均 增加了约16%;液氮中贮藏的样品在不同时间下测定其维生素C含量并无显著变化,测得维生素C含量的RSD均小 于2%。利用此方法可以测定较长时间保存样品中的维生素C,可满足高通量、高准确率的要求,有利于油菜的菜用 营养和育种研究。  相似文献   

2.
为提高酸茶B族维生素含量,试验通过减少发酵时长和添加外源菌剂发酵制备酸茶。测定发酵过程中酸茶不同维生素B的含量,采用SPSS 12.0对所得试验结果进行统计学处理。结果表明:与其他茶类相比,厌氧发酵的酸茶维生素B2含量较高,而其他B族维生素含量均较低,尤其是维生素B3和B5。缩短发酵时长有利于酸茶维生素B3和B5的积累,外源添加酵母菌和乳杆菌有助于提高酸茶维生素B3含量,接混合菌能够增加维生素B3含量但显著降低维生素B2和B6含量水平。表明缩短发酵时长与添加外源酵母菌或乳杆菌有助于提升酸茶B族维生素含量。  相似文献   

3.
吃茶叶有益     
科学证实,绿茶中许多成分对人体保健卓有功效,尤其在降脂、防癌、抗衰老方面的功效,导致了喝绿茶热。在煎茶过程中,绿茶所含的维生素A原和维生素E完全消失,所含钙、铁和维生素C减少。为此,研究者建议,相当湖三杯所用的茶叶数量,可得到每天所需维生素E50%和维生素A原的20%,目前,日本市场上开始销售可吃的绿茶粉。从各种风味菜到牛排、汉堡包、意大利面条和色拉等都可以加绿茶粉。绿茶粉还可广泛用于制作冰淇淋和口香糖。吃茶叶有益@王秀良  相似文献   

4.
以2%草酸溶液为提取溶剂,超声提取维生素C。在254 nm波长下,以0.05 mol/L磷酸二氢钾∶甲醇(90∶10)为流动相,采用HPLC法,检测出石屏、普洱、西双版纳和建水共4个产地树头菜嫩叶中维生素C含量分别为0.79、1.4、1.5和1.6 mg/g,其中建水产地的维生素C含量最高,石屏产地的含量最低。该方法准确可靠,可作为树头菜中维生素C含量的测定。  相似文献   

5.
马铃薯块茎中的维生素C吕文河,白雅梅(东北农业大学)(黑龙江省气象科学研究所)马铃薯块茎中含有大量的维生素C,是人类获得维生素C的一个重要来源。因此,众多研究者对马铃薯块茎中维生素C含量的分布、变化以及影响维生素C含量的因素做了广泛的研究。维生素C在...  相似文献   

6.
维生素E抗油脂氧化效果的研究   总被引:4,自引:0,他引:4  
使用柠檬酸或维生素C作为增效剂提高维生素E抗氧化效果研究表明,以柠檬酸作为增效剂添加于猪油中,60℃烘箱储存,维生素E的抗氧化性比单独使用维生素E效果好。柠檬酸或维生素C添加于机榨菜籽油中,温室储存,维生素E的抗氧化效果明显提高。柠檬酸或维生素C添加于精炼棉籽油中,室温储存,维生素E的抗氧化效果无明显提高。  相似文献   

7.
马铃薯块茎中维生素C含量的变化张培英,吕文河,孙丽,陈伊里,肖增宽(东北农业大学哈尔滨150030)1前言马铃薯是世界公认的营养丰富、美味可口的食品,尤其含有丰富的维生素C。维生素C在块茎中是以还原型(抗坏血酸)和氧化型(脱氢抗坏血酸)两种形式存在的...  相似文献   

8.
大豆维生素E   总被引:3,自引:0,他引:3  
维生素是生物生长和新陈代谢所必需的微量有机物,目前世界上发现的维生素已有20多种。  相似文献   

9.
为准确测定反式维生素K1的含量,建立了基于固相萃取-高效液相色谱串联质谱的甘蓝型油菜(Brassica napus L.)菜薹反式维生素K1高灵敏检测技术。样品经正己烷提取、中性氧化铝柱净化后,用C30反相色谱柱,以甲醇 (含0.025%甲酸+2.5 mmol/L甲酸铵)为流动相,采用选择反应监测(selected reaction monitoring, SRM)模式进行定量分析,20 min内可实现顺反异构体色谱分离。方法学考察结果显示,反式维生素K1在范围内线性关系良好,相关系数为0.9985。该方法检出限为0.29 μg/kg,定量限为0.95 μg/kg。回收率为87.5%~117.6%,精密度(RSD)在0.72% ~9.59%之间。利用该方法对油菜薹和反式维生素K1含量高的3种蔬菜进行分析,发现油菜薹中反式维生素K1含量为340.08 μg/100g,高于小白菜(B. rapa spp. chinensis,260.93 μg/100g)、西兰花(B. oleracea var. Italic Planch, 167.65 μg/100g)和结球甘蓝(B. oleracea var. capitata,151.11 μg/100g)。本文建立的蔬菜中反式维生素K1准确定量分析方法操作简单、灵敏度高、结果准确。同时比较发现油菜薹是一种富含维生素K1的蔬菜。   相似文献   

10.
胚芽米最初由日本研制生产,其精度接近普通精白米,但保留了80%的胚芽,营养丰富,含有维生素A、B、C尤其是富含维生素B1。脱脂米普通大米中含脂肪较多,在贮藏还程中脂肪酸度易升高,影响大米的质量。若从大众中提取部分脂肪,不仅可以减少脂肪氧化的可能,而且加工出来的大米洁白、无油、贮藏时间长。强化米美国的研究人员将吸足维生素B1、B12、烟酸和铁离子溶液的大米,涂上一层水溶性蛋白质的酒精薄膜后再淘洗,维生素就不致被破坏,蒸煮时,薄膜溶化,大米所附吸的营养使均匀地散在米饭中。上无米由意大利生产。这种求是将葡萄放…  相似文献   

11.

Background  

Many physiological processes of mammalian species exhibit daily rhythmicity. An intrinsic relationship exists between fat soluble vitamins (A, D, E and K) and several body functions. Few investigations on the rhythmic pattern of vitamins in domestic animals have been carried out. The present study evaluated the circadian rhythmicity of fat soluble vitamins in the horse.  相似文献   

12.
HPLC法测定菠萝果实中8种维生素含量的研究   总被引:1,自引:0,他引:1  
优化了利用高效液相色谱法测定菠萝果实中脂溶性维生素(VA、VE)和水溶性维生素(VC、 VB3、 VB12、 VB6、 VB2、 VB1)的方法; 脂溶性维生素以甲醇 ∶ 乙酸乙酯(V甲醇 ∶ V乙酸乙酯=95 ∶ 5)溶液为流动相, 流速为1.0 mL/min, 柱温25 ℃, 检测波长275 nm。 水溶性维生素以0.005 mol/mL己烷磺酸钠(pH3.2)∶ 甲醇(V乙烷磺酸钠∶ V甲醇=7∶ 3)为流动相, 流速为1.0 mL/min, 柱温30 ℃,于254 nm处测定吸光值。试验结果表明: 其线性相关系数在0.999 7~1.000 0之间, 线性关系良好。VA、 VE的峰面积RSD分别为1.48%、1.31%;VC、 VB3、 VB12、 VB6、 VB2和VBl的峰面积RSD分别为1.35%、 1.78%、 1.50%、 1.52%、 0.93%和1.10%。VA、 VC、 VB3、 VB6的平均加样回收率分别为94.2%、 102.3%、 91.0%、 95.2%。  相似文献   

13.
The objective of the project was to determine the bioavailability of selected B vitamins (niacin, pantothenic acid and thiamin) to humans from wet and dry milled maize brans which were coarsely or finely ground. Using a double cross-over design, the nine subjects were fed laboratory controlled diets containing unsupplemented bread or bread supplemented with finely ground, wet milled maize bran; coarsely ground, wet milled maize bran; finely ground, dry milled corn bran; or coarsely ground, dry milled maize bran. Subjects made complete collections of urine throughout the study which were analyzed for contents of the test vitamins. Although varying somewhat among vitamins, in general, better apparent bioavailability was achieved with the finely ground, dry milled maize bran than with the other test brans.  相似文献   

14.
In this study, multiple shoot induction and whole plant regeneration from decapitated embryo axes of three chick peal genotypes including MCC252, MCC283 and MCC505 were evaluated on modified Murashige and Skoog's medium (MMS) which, its vitamins were replaced by vitamins of B5 medium, supplemented with varied concentration of thidiazuron (0.1, 0.2 mg L(-1)) or 6-benzylaminopurin (1,2 mg L(-1)) or zeatin (1, 2 mg L(-1)) treatments. BAP was found to be the most effective cytokinin in normal multiple shoot induction. Shoots were elongated on growth regulator-free medium and then rooted on two media containing 1/4 MMS salts and B5 vitamins + 3% sucrose + 0.8% agar with indol-3-butyric acid (0.4 or 1 mg L(-1)). The highest rooting frequency resulted in a medium including 0.4 mg L(-1) IBA. It was found that different shoot induction media also positively affected rooting, where a medium with 2 mg L(-1) BAP in MCC252/MCC505 and a medium with 2 mg L(-1) zeatin in MCC283 were the best media in shoot induction that produced high frequency, thick spread roots. Plantlets were preliminary acclimatized in liquid medium (1/4 MMS salts and B5 vitamins + 3% sucrose + 0.4 mg L(-1) IBA) for 7 to 14 days, then transferred to pots filled by cocopit: perlite (1:1) and kept in a growth chamber until their shoots and roots were well developed. This resulted in more than 70% survival rate.  相似文献   

15.
Amaranth seeds can be popped by heating. The traditional method of popping in a skillet is simple, but it is difficult to control the heating time and temperature. To overcome these disadvantages, we developed a fluidized bed continuous processing system based on hot air heating for producing popped amaranth seeds in bulk. Using this system, we evaluated the effects of heat treatment at 260 °C for 15 s on the contents of B-group vitamins and essential and trace elements in amaranth seeds. The results showed that the treatment did not affect the content of B-group vitamins, and the recovery for essential and trace elements was 97–196 %. This popping system is useful for processing amaranth seeds in terms of the product quality and nutrition.  相似文献   

16.
Rye, wheat, barley, rice, maize and sorghum were milled into more or less refined fractions, and the content of thiamin, riboflavin, vitamin B6, folate, biotin, niacin and tryptophan were determined. Differences in vitamin content between the different cereal grains were rather small. Refining resulted in marked losses of all vitamins studied. On average, 70%–80% of the vitamins were lost during the milling process. The lowest vitamin content was found in highly refined rice, containing only about 5% of the folate and 10% of the niacin present in brown rice. Maize had a low content of tryptophan, and the concentration was greatly reduced by degerming. For the other cereal grains, milling had only a slight effect on tryptophan concentrations.  相似文献   

17.
Background: Iron deficiency anemia is one of the major causes of morbidity and mortality worldwide. Evidences from epidemiological and clinical studies suggest a possible correlation between antioxidant levels and the anemic disease risk. The present work is to investigate antioxidant levels and lipid peroxidation in anemic patients. Methods: A number of 30 patients (15 males and 15 females) were selected for the study. Likewise, 30 age- and gender-matched healthy volunteers (15 males and 15 females) were selected with their informed consent. Patients and healthy subjects were supplemented with vitamins C and E for 15 days. The lipid peroxidation both in plasma and erythrocyte lysates was determined by thiobarbituric acid reactive substances and lipid peroxides. The antioxidant vitamins A, C, and E and total antioxidant activity were also analyzed. The antioxidant enzyme superoxide dismutase, catalase, and glutathione peroxidase were also determined. Results: Based on analysis, we found that the increase in lipid peroxidation was higher in the anemic subjects before vitamin supplementation, which was statistically significant at P<0.05. The antioxidant enzymes were higher in the patients before antioxidant supplementation when compared with patients after vitamin supplementation. Conclusion: Our data revealed higher oxidative stress before vitamin supplementation in iron deficiency anemic patients and after supplementation, lower lipid peroxidation and increased antioxidant vitamins were achieved. Key Words: Iron deficiency anemia, Lipid hydroperoxides (LOOH), Vitamin C, Vitamin E, Thiobarbituric acid reactive substances (TBARS)  相似文献   

18.
Augustin  Jorg  Johnson  S. R.  Teitzel  C.  True  R. H.  Hogan  J. M.  Toma  R. B.  Shaw  R. L.  Deutsch  R. M. 《American Journal of Potato Research》1978,55(12):653-662
American Journal of Potato Research - The retention of water-soluble vitamins by several potato varieties using various home preparation methods was investigated. Retention values in general...  相似文献   

19.
以玉米杂交种郑单958为试验材料,采用不同质量浓度50、100、200 mg/L的水溶性维生素V_(B1)、V_(B2)、V_(B6)、V_(B12)、V_C、V_H、V_(PP)浸种24 h,处理后分析玉米种子萌发及胚芽和根生长中脯氨酸等可溶性调节物质情况。结果表明,供试维生素在100、200 mg/L处理下基本都呈现对种子萌发指数的促进,其中,100 mg/L维生素处理对种子萌发率促进效果显著;200 mg/L维生素处理对种子发芽势显著促进作用;50 mg/L维生素对上述3个指标的影响不同。与未处理对照相比,不同种类维生素和不同质量浓度的同一维生素对根冠比影响不同。维生素浸种均可引起玉米胚芽可溶性糖含量显著升高,外源维生素浸种处理可显著影响玉米种子萌发和胚芽及胚根的生长,且不同维生素在不同浓度下对各生长指标影响及脯氨酸等可溶性调节物质变化不尽相同,对种子萌发呈显著促进作用的V_(B2)和V_(B12)在玉米种子萌发中应用前景较好。  相似文献   

20.
茶叶贮藏过程中品质变化及其影响因素研究进展   总被引:3,自引:0,他引:3  
崔峰  骆耀平  陈一心 《茶叶》2008,34(1):2-5
本文介绍了茶叶贮藏过程中,温度、湿度、光照和氧气等外界环境因素对其品质的影响,以及贮藏中茶叶品质成分,如含水量、氨基酸、茶多酚、叶绿素和维生素等的变化;并对目前生产与研究提出了初步想法。  相似文献   

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