奇异球菌R13中类胡萝卜素的稳定性研究毕业论文
2022-01-26 11:10:41
论文总字数:15677字
摘 要
类胡萝卜素是一类以异戊二烯为单位的萜类化合物,具有显著的抗氧化功能,可以用在工业上,作为食物和脂肪的着色剂,如β-胡萝卜素、番茄红素、玉米黄质、叶黄素等。有些类胡萝卜素对于人体必不可少,如缺维生素A会导致夜盲症。本研究针对奇异球菌属中发现的新菌株Deinococcus xibeiensis R13提取出的类胡萝卜素,探讨温度、pH值、酸及碱溶液、氧化还原剂、金属离子和食品添加剂等对菌株D.xibeiensis R13中类胡萝卜素稳定性的影响。通过对Deinococcus xibeiensis R13中提取出的类胡萝卜素进行实验得出,在低温环境下,类胡萝卜素损失量少,稳定性好;高温环境会加速类胡萝卜素降解,稳定性下降。类胡萝卜素在黑暗条件下稳定,在光照下不稳定,并且在紫外光下比白炽灯下稳定。在酸性和碱性条件下类胡萝卜素的保存率会在短时间内急剧下降,并且在酸性条件下的保存率比碱性条件更低。不同浓度的氧化剂几乎均不利于类胡萝卜素的稳定性,而在类胡萝卜素中加入还原剂能够增强稳定性,以Vc和BHT的效果最佳。添加Fe3 、Cu2 和食盐会降低类胡萝卜素的稳定性;而添加木糖、葡萄糖和Mn2 可以增强类胡萝卜素的稳定性。本实验可以为研究菌株D.xibeiensis R13的耐辐射机制提供了基础。
关键词:类胡萝卜素 Deinococcus xibeiensis R13 稳定性
Study on the stability of carotenoids in Deinococcus xibeiensis R13
Abstract
Carotenoids are lipophilic polyisoprene from 8 classes of isoprene. Carotenoids have significant antioxidant properties and can be used in industry as colorants for food and fat, such as -carotene, lycopene, zeaxanthin, lutein, etc. Some carotenoids are essential, such as vitamin A, which can lead to night blindness.In this study, the carotenoids extracted from Deinococcus xibeiensis R13, a new strain found in the genus xenococcus, were studied to investigate the effects of temperature, pH value, acid and alkali solution, oxidative reductant, metal ions and food additives on the stability of carotenoids in D. xibeiensis R13 strain.Through experiments on the carotenoids extracted from Deinococcus xibeiensis R13, it can be concluded that the carotenoids are stable, less loss and easy to preserve at low temperature. High temperature environment will accelerate the degradation of carotenoids and decrease their stability. Carotenoids are stable in dark conditions, unstable in light, and more stable in ultraviolet light than in incandescent light. Under acidic and alkaline conditions, the retention rate of carotenoids will drop sharply in a short time, and the retention rate is lower under acidic conditions than under alkaline conditions. Oxidants had an effect on the stability of carotenoids. At the same time, adding reductant to carotenoids could enhance the stability, and Vc and BHT had the best effect. The addition of Fe3 , Cu2 and salt reduced the stability of carotenoids. The addition of xylose, glucose and Mn2 can enhance the stability of carotenoids. This experiment may provide a basis for studying the radiation resistance mechanism of strain D.xibeiensis R13.
Key Words: Carotenoids; Deinococcus xibeiensis R13; Stability
目 录
摘 要 I
Abstract II
1.1 耐辐射奇异球菌的介绍 1
1.1.1 耐辐射奇异球菌的简介 1
1.1.2 耐辐射奇异球菌的研究进展 1
1.2 类胡萝卜素的介绍 2
1.2.1 类胡萝卜素的简介 2
1.2.2 类胡萝卜素的功能 3
1.2.3 类胡萝卜素的特性 3
1.3 类胡萝卜素的生产方法 4
1.4 本研究的研究意义 4
第二章 实验材料与方法 6
2.1 实验材料 6
2.2实验方法 7
2.2.1 培养基及溶液配制 7
2.2.2 类胡萝卜素色素的提取 7
2.2.3 类胡萝卜素稳定性测定 7
第三章 实验结果与讨论 10
3.1 温度对类胡萝卜素稳定性的影响 10
3.2 光照对类胡萝卜素稳定性的影响 10
3.3 pH及酸碱溶液对类胡萝卜素稳定性的影响 11
3.4 氧化还原剂对类胡萝卜素稳定性的影响 13
3.5 金属离子对类胡萝卜素稳定性的影响 14
3.6 食品添加剂对类胡萝卜素稳定性的影响 15
第四章 结论 17
参考文献 18
致谢 21
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