Author: Munawwer Rasheed, Mansoor Ahmed , Amir Hassan ,Urooj Nazim , Rafeeq Alam Khan, Mustafa Kamal, Mohammad Abdur Rashid
Publishing Date: 2017
Volume 30 Issue 5
Gallbladders bile of three well known commercial fish of South Asia region named Muraenesox bagio (locally called bam), Pomadasys argenteus (dother) and Lobeo rohita (rohu) were analysed on GC-MS, after derivatising the bile alcohols and bile acids as trimethylsilyl ether and trimethylsilyl-methyl ester, respectively. Cholic acid (1) and chenodeoxycholic acid (2) were found as major bile acids in all three species. Major bile alcohol in these fish was cholesterol (4), which was not detected in freshwater specie (L. rohita). M. bagio was also found to contain 3α,7α,12α- trihydroxy-23-cholesten-26-oic acid (3). Other bile acids and bile alcohols identified in L. rohita were allo deoxycholic acid (5), 12-oxo-3α-hydroxycholanic acid (6), 3α,7α,12α-trihydroxy-24-cholesten-26-oic acid (7), 5α- and 5β- anhydrocyprinol (8 and 9, respectively) and 5β-homocholane-3α,7α,12α-25-tetrol (10). Besides acting as emulsifying agent in the digestion process, in non-mammalian vertebrates, e.g., fish, reptiles, etc. the analytical and elucidative studies on the bile contents disclose the diversity in metabolic pathways of cholesterol and indicate the existence of molecular evolution in the basic C27 skeleton of cholesterol.
Keywords: GC-MS, marine and fresh water fish