| 摘要: |
| 工厂化养殖中产生的环境压力，会导致对虾应激反应的发生以及体色的减弱。为了探究胁迫下对虾体内虾青素的消耗规律以及对虾的着色与抗氧化之间的关联性，本研究通过虾青素强化后盐度胁迫的方法进行了实验。结果表明，与强化前相比，虾青素强化后植物源(夏侧金盏花)虾青素(d-AST)、合成虾青素(p-AST)处理的对虾肝胰腺中虾青素含量分别增加48.0%和17.5%；虾壳中分别增加42.8%和45.2%。富含酯化型虾青素的d-AST在肝胰腺中具有更高的沉积量；而由游离虾青素组成的p-AST在虾壳中具有更高的沉积量，不同形式的虾青素在不同组织中的沉积具有一定的偏好性。两个处理组对虾的体色明显增强。与盐度胁迫前相比，胁迫后d-AST、p-AST肝胰腺中虾青素含量分别减少了15.1%和5.7%，对照组（Ctrl）含量无变化；虾壳中分别减少了17.8%、52.9%和14.3%，各组对虾的体色均显著减弱。胁迫24 h检测到编码虾青素转运蛋白β-1,3-葡聚糖结合蛋白(βGBP-HDL)基因的显著上调表达，可能与虾壳中虾青素的减少有关。随着胁迫的进行，与对照组相比，两个处理组的抗氧化基因均呈现上调表达的趋势；各组抗氧化能力呈现先上升后下降的趋势，并在48h时达到最大值，d-AST、p-AST分别为对照组的1.35和1.30倍。据此，我们推测对虾体内的虾青素是按照资源权衡的原则在着色和抗氧化功能中进行分配的，在遭受环境胁迫时，对虾会优先将用于着色部分的虾青素(虾壳中)转运至肝胰腺中参与抗氧化，进而表现为体色的减弱和抗氧化能力的上升。 |
| 关键词: 凡纳滨对虾 虾青素 体色 抗氧化 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金-山东联合基金 (U1706209) |
|
| Resource tradeoff between coloring and antioxidation of astaxanthin in Litopenaeus vannamei under salinity stress |
|
YANG Mengxuan1, WANG Baojie1, LIU Mei2, JIANG Keyong1, Zhong Chen2, WANG Lei1
|
|
1.CAS and Shandong Province Key Laboratory of Experimental Marine Biology,Institute of Oceanology,Chinese Academy of Sciences;2.Aquatic Organisms Quality Evaluation and Utilization Engineering Research Center,Marine Science Research Institute of Shandong Province
|
| Abstract: |
| The environmental pressure produced in industrial culture will lead to the occurrence of stress reaction and the weakening of body color of shrimp. The results showed that the contents of astaxanthin (d-AST) and synthetic astaxanthin (p-AST) in hepatopancreas of prawns treated with astaxanthin were increased by 48.0% and 17.5%, respectively, compared with those treated with astaxanthin. Shrimp shells increased by 42.8% and 45.2%, respectively. d-AST rich in esterified astaxanthin had higher deposition amount in hepatopancreas. p-AST composed of free astaxanthin has higher deposition amount in shrimp shell, and different forms of astaxanthin in different tissues have a certain preference. The body color of prawn in two treatment groups was significantly enhanced. Compared with before salinity stress, the astaxanthin content in d-AST and p-AST hepatopancreas decreased by 15.1% and 5.7% after salinity stress, respectively, while the content of control group (Ctrl) did not change. The body color of prawn in all groups was significantly decreased by 17.8%, 52.9% and 14.3%, respectively. The expression of the gene encoding astaxanthin transporter β-1, 3-glucan-binding protein (βGBP-HDL) was significantly up-regulated after 24h stress, which may be related to the reduction of astaxanthin in shrimp shell. With the progression of stress, the expression of antioxidant genes in the two treatment groups showed an up-regulated trend compared with the control group. The antioxidant capacity of each group increased first and then decreased, and reached the maximum value at 48h. d-AST and p-AST were 1.35 and 1.30 times of that of the control group, respectively. Therefore, we speculated that the astaxanthin in prawn is allocated in the pigmentation and antioxidant function according to the principle of resource balance. Under environmental stress, the astaxanthin used in the pigmentation part (shrimp shell) will be preferentally transported to the hepatopancreas to participate in antioxidant function, which will be manifested as the weakening of body color and the increase of antioxidant capacity. |
| Key words: Litopenaeus vannamei, Astaxanthin, Body color, Antioxidation |