Predicting the positional distribution of docosahexaenoic and docosapentaenoic acids in aquatic animal triglycerides

The positional distribution of 22∶6 and 22∶5 in aquatic animal triglycerides can be predicted by simple proportionality equations of the type y=kx . The mole % 22∶6 at the 1, 2, or 3 position ( y ) is obtained by multiplying the proportionality constant for that position ( k 1 , k 2 , or k 3 ) times the mole % 22∶6 in the total triglycerides ( x ). For fish and invertebrate triglycerides, k 1 =0.28, k 2 =2.06, and k 3 =0.66. For marine mammal blubber triglycerides, k 1 =0.94, k 2 =0.22, and k 3 =1.84. The same equations apply to both 22∶6 and 22∶5.