After the Soxhlet method [23], which is considered unsuitable for lipid extraction of fish tissues because of its dependency on conditions which are difficult to control (i.e., no precise determination of extraction cycles due to continuous flow), the Bligh and Dyer method [21] is probably the second most common lipid extraction procedure reported in the scientific literature.
Where unreported extraction of fish from major stocks is not included this can bias both single species stock assessment and ecosystem-based analyses in a dangerous direction of allowing more fishing than would otherwise be thought sustainable.
Climate change almost always exacerbates the problems caused by other environmental stressors including: land use change and the consequent habitat fragmentation and degradation; extraction of timber, fish, water, and other resources; biological disturbance such as the introduction of non-native invasive species, disease, and pests; and chemical, heavy metal, and nutrient pollution.
Some of us rely on ocean wildlife as a source of locally caught and locally consumed food, but industrial-scale extraction of shrimp, fish and other animals for luxury markets, fertiliser, oil and food for domestic animals is swiftly depleting wild populations both in coastal areas and increasingly in the high seas, beyond local jurisdiction.
EPA and DHA were obtained by extraction and fractionation of fish industries waste, such as fish heads, produced for fish canning.
Some procedures for solvent extraction might be principally suitable for extraction of lipids from fish tissues, but relatively large sample volumes are required (e.g., [20]).
An alternative method for the quantitative extraction of lipids from fish using non-halogenated solvents was described by Jensen et al. [6].
The results of this study show good recoveries and range from 70 to 76% for the extraction of LMG in fish tissue (tilapia).
These biotechnological processes represent a sustainable alternative to the extraction of PUFA from fish oil (Apt and Behrens 1999; Barclay et al. 1994; Barclay 1992; Kyle and Gladue 1991; Kyle et al. 1991; Mendes et al. 2009; Wynn et al. 2005).
It can be assumed that the results of all seven labs which use solvent extraction procedures for analysis of fish samples are comparable.
However, only the use of suitable extraction techniques guarantees the complete extraction of total lipids from fish samples in bioaccumulation studies which is required to ensure the correct lipid normalization of BCF values.
