SPECIES IDENTIFICATION BY THE POSITIONAL ANALYSIS OF FATTY-ACID COMPOSITION IN TRIACYLGLYCERIDE OF ADIPOSE AND BONE TISSUES

In a new attempt at species identification, the total composition and positional distribution of fatty acid in triacylglyceride (TG) of adip ose and bone tissues were analyzed in human, bovine, pig, dog, cat and chicken tissues. Although the total fatty acid compositions of bovine and pig tissues were significantly different from those of human (dif ferent in more than half the fatty acids tested), dog, cat and chicken tissues showed a comparatively similar composition to human fatty aci ds composed of TG in both tissues. The TG in these tissues was also su bjected to stereospecific analysis using pancreatic lipase, that is, t he fatty acid distribution in positions 1,3 (not distinguished between 1 and 3) and 2 of the TG were determined. The distribution of fatty a cids among the positions 1,3 and 2 in the TG of animal adipose and bon e tissues was non-random. The distribution between position 2 and posi tions 1,3 seems to be governed by chain length and unsaturation in eac h animal. The shorter and more unsaturated fatty acids showed a greate r tendency to occupy position 2 of TG, Although this rule appeared in all animals except the pig, the distribution of each fatty acid into p osition 2 was species-specific. The positional distribution of fatty a cid in TG was identical among the same species and in different region s of the same body. Thus, even when species identification is difficul t using the pattern of total fatty acid composition, the analysis of t he positional distribution of fatty acid makes it possible to determin e the species, From the present results, the evaluation of positional distribution of fatty acid in the TG is a useful tool fur the identifi cation oi human tissues.