Fatty acid breakdown energy yield

Catabolism The breakdown of complex molecules to simpler ones to yield energy (e.g., triacylglycerols to fatty acids) and the inactivation of physiologically active molecules (e.g., acetylcholine to choline and acetic acid). 

The degradation of fatty acids occurs by an oxidation process in the mitochondria. The breakdown of the 16-carbon saturated fatty acid, palmitate, occurs in blocks of two carbon atoms by a cyclical process. The active substrate is the acyl-CoA derivative of the fatty acid. Each cycle involves four discrete enzymatic steps. In the process of oxidation the energy is sequestered in the form of reduced coenzymes of FAD and NAD+. These reduced coenzymes lead to ATP production through the respiratory chain. The oxidation of fatty acids yields more energy per carbon than the oxidation of glucose because saturated fatty acids are in the fully reduced state. 

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