Original Research ARTICLE
Comparison of the biochemical composition and nutritional quality between diploid and triploid Hong Kong oysters, Crassostrea hongkongensis
- 1South China Sea Institute of Oceanology (CAS), China
- 2University of Chinese Academy of Sciences (UCAS), China
This study is the first systematic comparison of the biochemical composition and nutritional quality between diploid and triploid Hong Kong oysters, Crassostrea hongkongensis. Results showed that in the reproductive season, the glycogen content in five tissues (gill, mantle, adductor muscle, labial palps and gonad) was significantly higher (P < 0.05) in triploids than in diploids, with odds ratios (ORs) of 96.26%, 60.17%, 72.59%, 53.56% and 128.52%, respectively. In the non-reproductive phase significant differences in glycogen content (P < 0.05) between diploid and triploid oysters existed only in gill and gonad. In both diploid and triploid Hong Kong oysters, quantitative real-time PCR analysis of the glycogen synthesis gene (ChGS) and glycogen phosphorylase gene (ChGP) showed that the gene expression patterns matched the pattern of variation in glycogen content. Moreover, in both the reproductive and the non-reproductive phases, triploid Hong Kong oysters had a well balance of essential amino acids and were thus a well source of high-quality protein.
Surprisingly, in both phases, significantly higher (P < 0.05) percentages of four essential fatty acids (α-linolenic acid, linoleic acid, eicosapentaenoic acid and docosahexaenoic acid) were observed in triploids than in diploids. Additionally, the ratio of n-3/n-6 polyunsaturated fatty acids (PUFAs) was much higher in triploids than that in diploids. Variations in Biochemical composition were consistent with the relative expression of the citrate synthase gene (ChCS) and the α-ketoglutarate dehydrogenase gene (ChKD), which are key enzyme genes of the tricarboxylic acid cycle. Overall, the triploid Hong Kong oyster has a better nutritional value and taste than the diploid in terms of glycogen content, protein quality and fatty acid content.
Keywords: Crassostrea hongkongensis, diploid, Triploid, Biochemical compositions, nutritional quality, Metabolic pathways
Received: 28 Aug 2018;
Accepted: 08 Nov 2018.
Edited by:Xiaotong Wang, Ludong University, China
Reviewed by:Lorenzo Gallus, Università di Genova, Italy
Filippo Garofalo, Università della Calabria, Italy
Weiwei You, Xiamen University, China
Copyright: © 2018 Qin, Zhang, Ma, Wu, Xiao, Li, Mo and Yu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
PhD. Yuehuan Zhang, South China Sea Institute of Oceanology (CAS), Guangzhou, China, email@example.com
Prof. Ziniu Yu, South China Sea Institute of Oceanology (CAS), Guangzhou, China, firstname.lastname@example.org