Aquaculture waste as food for amphipods: the case of Gammarus insensibilis in marsh ponds from southern Spain

Biosynthesis of Long-Chain Polyunsaturated Fatty Acids in Marine Gammarids: Molecular Cloning and Functional Characterisation of Three Fatty Acyl Elongases

“…There exists a growing interest in using gammarids in aquaculture associated with their nutritional profiles, characterised by relatively high contents of n-3 LC-PUFA [ 24 , 25 ]. Moreover, gammarids have shown an ability to be grown on a varied range of sidestreams from bio-based industries [ 28 , 30 , 31 , 33 ]. Recently, Alberts-Hubatsh et al [ 33 ] reported that the gammarids E. marinus and G. locusta had some capacity for “trophic upgrading”, implying that these crustaceans can bioconvert FA present in sidestreams from agriculture into high nutritional value LC-PUFA [ 33 ].…”

“…Gammarids, crustacean amphipods, are aquatic invertebrates that are abundant in benthic communities in virtually all aquatic environments [ 22 , 23 ]. Previous studies have shown that gammarids’ nutritional profiles are characterised by a high protein content, low levels of carbohydrates, and relatively high contents of n-3 LC-PUFAs [ 24 , 25 , 26 , 27 , 28 , 29 ]. Such characteristics, along with the possibility to establish high density cultures [ 25 , 30 , 31 ], have prompted interest for using gammarids in aquaculture [ 32 ].…”

“…Such characteristics, along with the possibility to establish high density cultures [ 25 , 30 , 31 ], have prompted interest for using gammarids in aquaculture [ 32 ]. Importantly, some investigations reported on the ability of gammarids to be used in a wide range of sidestreams, in bioindustries such as aquaculture, forestry and agriculture [ 28 , 30 , 31 , 33 ]. Consequently, gammarids arise as promising candidates to apply circular economy principles by which sidestreams can be utilised for the production of biomass with high nutritional value.…”

“…On one hand, front-end desaturases (Fad) introduce double bonds (unsaturations) into polyunsaturated fatty acid (PUFA) substrates; on the other hand, elongation of very long-chain fatty acid (Elovl) proteins (or commonly known as “elongases”) catalyse the usually rate-limiting reaction (condensation) in the FA elongation pathway and results in the extension of the pre-existing FA in two carbons [ 35 ]. To the best of our knowledge, no studies have reported on the molecular and functional characterisation of fad and elovl genes from gammarids, and the LC-PUFA biosynthetic capacity of gammarids has been only inferred from feeding experiments assessing the impact of dietary FA on body FA composition [ 24 , 25 , 26 , 28 , 33 ]. While the presence of Fad-like enzymes in crustaceans remains to be clarified [ 6 ], elovl genes with roles in LC-PUFA biosynthesis have been recently reported in crabs such as the mud crab Scylla paramamosain [ 36 ], the orange mud crab Scylla olivacea [ 37 , 38 ] and the swimming crab Portunus trituberculatus [ 39 ].…”

The aquaponic principle—It is all about coupling

“…Without ‘water’, an aquaponic definition would include cases where aquaculture and hydroponics are far apart and nutrients are transported by other means, such as in a dry state. Aquaculture waste would be a resource, for inter alia plant cultivation or as food for amphipods, 58 but the principle of direct coupling would be abolished. (6) The maximal spatial separation of the aquaponic units covered by definition remains open, but we restrict the transport medium to water which limits the practical distances somewhat.…”