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1.
本文提出了利用反相离子对色谱法,简单,快速,准确同时定量测定饲料添加剂中的烟酸,烟酰胺,盐酸吡哆辛,氰钴胺素,核黄素和硫胺素。样品前处理简单,六个维生素能在12min内获得满意的分离,各组份之间的分离度Rs大于1.60。各个维生素的回收率在87.0~101.0%,相对偏差为3.1~2.0%。色谱柱为LichrosorbRP-18 250×φ5mm,流动相为甲醇/水,0.25%TEA,1.25mmol/l PICB-5,3.75mmol/l PICB-7,pH3.00,紫外可变波长检测器采用MAXPL操作方式λ 1=254nm,λ_2=280nm,λ_3=354nm,流速1.1 nl/min。  相似文献   
2.
In vegetable brassicas, cytoplasmic male sterility (CMS) system is the most preferred mechanism for hybrid seed production and Ogura cybrid cytoplasm is the only source used widely. Effects of the alien cybrid cytoplasm on important quality traits need to be understood for their effective use in breeding programme. In analysing 38 Ogura cybrid cytoplasm‐based cauliflower CMS lines, it was revealed that introgression of Ogura cytoplasm resulted in significant alteration in important quality traits. Cupric reducing antioxidant activity and ferric reducing ability of plasma values were increased up to 5–10 times in different genotypes. Among 38 analysed CMS lines, concentration of plant pigments such as anthocyanin, total chlorophylls and ascorbic acid was reduced in 21, 17 and 32 genotypes, respectively. However, the concentration of total carotenoids and β‐carotene was elevated in most of the CMS lines and total carotenoid was increased up to 20 times in the CMS line, Ogu13‐85‐2A. The results indicate the role of nuclear–cytoplasmic interaction and mitochondrial genome in determining concentration of different quality traits.  相似文献   
3.
The objective was to investigate in a survey study the blood vitamin concentrations in healthy dogs fed non-specified commercial complete diets and in an intervention study to determine the effects of defined dietary vitamin intakes on blood vitamin levels and hair and skin condition. Sixty-four privately owned dogs, aged from 1 to 8 years, without history of skin or coat problems were included. All animals were fed commercial complete diets with uncertain vitamin concentrations before enrolment. The animals were assigned, according to weight and gender, to four groups with graded vitamin intakes. The blood vitamin levels and skin and coat quality of the dogs were investigated at days 0 and day 122. Coat and hair condition was not influenced by the experimental diets. The retinol concentrations were reduced at the end of the experiment compared with the baseline levels, retinyl esters were not influenced. 25-Hydroxycholecalciferol decreased in all groups, alpha-tocopherol was constant or tended to decrease. Ascorbic acid, thiamine pyrophosphate and riboflavin concentrations were not affected by treatment, flavin adenine dinucleotide and pyridoxal-5'-phosphate were partially reduced on day 122. Cobalamin, pantothenate and biotin concentrations increased with higher dietary intakes, folate levels in tendency. In conclusion, this study gives a survey of blood vitamin concentrations in healthy dogs and provides a data base for the evaluation of the vitamin status in health and disease.  相似文献   
4.
采用反相高效液相色谱法测定不同海拔大叶碎米荠中的水溶性维生素C、维生素B6(吡多醇)和维生素B5(烟酸)的含量。色谱在HypersilC-8柱(5μm,4.0mm×250mm)上进行,以流动相A(1%乙酸含0.5%三乙胺,pH=4.5)与B(A-甲醇,50∶50)进行梯度洗脱,流速为1mL/min,检测波长为275nm,室温。样品其回收率为98%~105.5%(RSD1%~5%)。不同海拔的维生素含量存在一定差异,烟酸在1500m时含量最高;而维生素C与吡多醇在2100m时含量最高。人工种植的大叶碎米荠与普通蔬菜(土豆、西红柿)相比,富含吡多醇和烟酸。  相似文献   
5.
There has been rapid development in the marine foodfishlarviculture technology in Europe since the early eighties,especially in the flat fish, turbot and halibut, and the bass andbream species. The most significant improvements in the eightieswere the introduction of light control, artificial reproductiontechniques, appropriate water treatment and the use of rotifersand Artemia nauplii of specific sizes and in the late eightiesand early nineties the quality enhancement of live food organismsusing specific enrichment techniques. Present research is focusedon the implementation of several microbial techniques to improvethe hygiene of live prey and fish.Many of the modern larviculture techniques being used in marine foodfish could be adapted for application in the ornamental fish industry. For examples, research in the Onamental Fish Section, Primary Production Department, Singapore has demonstrated that the use of freshwater rotifers and Artemia nauplii would enable artificial rearing of Discus in the absence of the parent fish and improve the larval performance of Gouramis and Tetra larvae. The use of such small live food organisms is likely to facilitate breeding of new fish species with small larvae. Research has also indicated that the use of diets containing vitamin C and certain immuno-stimulants improved the stress resistance of guppy. Such techniques would have important application in the fish transport, an important aspect in the ornamental fish industry  相似文献   
6.
A pilot study was performed to investigate the impact of dietary vitamin D on circulating 25-hydroxyvitamin D (25[OH]D) metabolite concentrations in sugar gliders (Petaurus breviceps). The study with diets containing 0, 0.2 (low), or 0.4 (moderate) International Units vitamin D3 per gram of dry matter and fed to adults at 2 locations. Serum 25[OH]D concentrations did not differ between animals fed produce only (no added vitamin D–either D2 or D3) for 3 weeks (8.83 ± 0.98 nmol/L), n?=?6, or low dietary levels (7.86 ± 3.80 nmol/L), n?=?7, continuously for multiple years. Conversely, animals consuming diets containing moderate vitamin D3 levels displayed increased circulating concentrations (15.00 ± 3.59), n?=?8, after 3 weeks. Despite the response to diets supplemented with vitamin D, overall metabolite levels were low and may indicate minimal metabolic dependence on this nutrient in sugar gliders, similar to processes documented in other hindgut fermenters.  相似文献   
7.
为了探明不同产地独蒜兰维生素的累积状况,采用高效液相色谱法(HPLC)对11个不同产地独蒜兰样品中的脂溶性和水溶性维生素的含量进行测定.结果表明:HPLC法能够有效测定独蒜兰的维生素;样品中VB6和VE的含量较为丰富,分别为115.8~857.2mg/100 g和13.4~185.7mg/100 g;独蒜兰中维生素的含量与其形状及大小没有直接的相关性,而不同产地来源的独蒜兰,其维生素的含量差异显著.  相似文献   
8.
糙米是一种天然保健食品,由其制备的糙米茶和发芽糙米茶营养丰富,具有促进血液通畅、大便通畅、小便通畅、美容、减肥和防癌的作用。文章简述了糙米茶与发芽糙米茶的功效与制作方法,以期为今后开展糙米茶相关研究提供参考。  相似文献   
9.
10.
The stability of two forms of vitamins, crystalline and fat-coated, during manufacturing processes and storage of fish feeds was investigated. After extrusion, vitamin recovery was generally lower than that found after pelleting. The recovery of coated forms after pelleting was higher than that of crystalline ones, especially for ascorbic acid, menadione, pyridoxine and folic acid. Coated forms were also found to be more resistant to extrusion than crystalline forms. No significant differences in vitamin losses during storage were found between pelleted and extruded feeds. However, losses of ascorbic acid, menadione and pyridoxine in both manufactured feeds were much greater in crystalline than in coated forms.  相似文献   
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