AAT Bioquest

What are the differences between fatty acid synthesis and beat-oxidation?

Posted October 12, 2023


Basis of differentiation 

Fatty acid synthesis

Beta oxidation 


Refers to a multi-step metabolic process in which fatty acids are produced from precursor molecule acetyl CoA  and NADPH molecules through a series of anabolic reactions by enzymes

Is a multi-step metabolic process in which fatty acid molecules are broken down to produce energy through a series of catabolic reactions by enzymes

Initiation of the process

Is initiates by acyl group carrier (ACP)

 Is initiated by with coenzyme A (CoA)


Occurs in the cytoplasm in both prokaryotes and eukaryotes 

Occurs in the cytoplasm of prokaryotes and mitochondria in eukaryotes

Type of reaction  

Is an anabolic reaction

Is a catabolic process

Enzymes involved 

Is catalyzed by the enzyme fatty acid synthase, a multi-enzyme complex

Is catalyzed by different enzymes at different stages of the oxidation process

Relationship with Energy  

Energy is used by this process  

Energy is released during this process

Relationship with ATP

Uses ATP

Produces high-energy molecule ATP

Reductants Used

Uses one reductant: 

  • NADPH (Nicotinamide Adenine Dinucleotide Phosphate Hydrogen)

Uses 2 reductants: 

  • NADH (Nicotinamide Adenine Dinucleotide Phosphate Hydrogen)
  • FADH (reduced form of Flavin Adenine Dinucleotide)
Additional resources

Mitochondrial fatty acid synthesis, fatty acids and mitochondrial physiology

Cell Meter™ Intracellular Colorimetric Lipid Peroxidation (MDA) Assay Kit