With the chemical formula C5H10N2O3, glutamine is one of 20 naturally occurring amino acids found in protein foods. It’s also the most abundant amino acid in the bloodstream. It makes up 30 percent to 35 percent of the amino acid nitrogen in your blood. A precursor to the neurotransmitter glutamate in your brain, glutamine is key to boosting your brain health. Whether your goal is to increase athletic performance, boost metabolism, improve recovery or even build muscle, research shows that L-glutamine can significantly aid your efforts. L-glutamine is an essential nutrient in cell cultures for energy production as well as protein and nucleic acid synthesis. However, L-glutamine in cell culture media spontaneously degrades, generating ammonia and pyrrolidine carboxylic acid as byproducts.