Free amino acid, 5′-Nucleotide, and lipid distribution in different tissues of blue mussel (Mytilis edulis L.) determined by mass spectrometry based metabolomics.

• Mussel viscera and gonad were rich in glutamate and glycine. • 5′-Nucleotides were abundant in mantle, foot, and adductor muscle. • Phospholipids in female mussel were higher than that in male. • Glycerides in male mussel were higher than that in female. Blue mussel (Mytilus edulis L.) is a popular, nutritional, and tasty mollusk. To better understand the composition of nutrients and improve further processing of the mussels, metabolomic approaches were used to analyze the free amino acids, 5ʹ-nucleotides, and lipid compositions of different tissues. Our results showed that the viscera and gonad were rich in glutamine and glycine. Adenosine 5ʹ-monophosphate, uridine 5ʹ-monophosphate, guanosine 5ʹ-monophosphate, and inosine 5ʹ-monophosphate were abundant in the mantle, foot, and adductor muscle. Three main types of lipids, phospholipids (PLs), glycerides, and fatty acids (FAs), were semi-quantified. PLs were mainly distributed in the gonad of male mussels and viscera, gonad, and mantles of female mussels. FAs were relatively high in the viscera of males and in the gonad and viscera of females. The viscera of females were rich in phosphatidylcholine, such as 16:0/22:6 and 16:0/20:5. Triglycerides were the key lipids for distinguishing different tissues, especially 16:0/18:1/18:3 and 16:0/18:4/20:5. [ABSTRACT FROM AUTHOR]