The majority of commercially available Glutamine sources offer only L-Glutamine, a synthetic, free amino acid. L-Glutamine has been shown to be unstable in the presence of heat, water, acid or base solutions, making L-Glutamine impractical to utilize in all but powdered food preparations.

Covalent Bonded Glutamine, on the other hand, has been shown to withstand processing temperatures of 180 degrees Fahrenheit for one hour or 250 degrees Fahrenheit for 15 minutes and pH variances in the range of 3.5 to 9.0. In addition, Covalent Bonded Glutamine is stable in aqueous solutions for prolonged periods of time. Covalent Bonded Glutamine can be used in all liquid and semi-solid food preparations. In addition, due to the instability of L-Glutamine in water and pH extremes, it is safe to assume that much of L-Glutamine decomposes once it passes into the human gastrointestinal tract. Gastric acid is equivalent to 0.1 Normal Hydrochloric Acid (pH less than 2) and at 98.6 degrees Fahrenheit and a pH below 2, L-Glutamine decomposes very quickly.

In addition, since L-Glutamine is a free amino acid, what percentage that does survive the pH extremes of the stomach is absorbed through the intestinal wall by a different mechanism than covalent bound amino acids. This free amino acid absorption mechanism is competitive, meaning that in an excess of free amino acids, only a certain percentage of any particular free amino acid will be absorbed.

Covalent Bonded Glutamine, on the other hand demonstrates improved retention in intestinal cells and the oligopeptides containing Glutamine will be absorbed through the intestinal wall by a less 'competitive' method. Studies by P.D. Fairclough et al., G.K. Grimble et al, and D.B.A. Silk et al, have shown that uptake of amino acids is faster and more 'even' from oligopeptide chains than from the equivalent free amino acid mixtures in the Human intestine. In other words, Covalent Bonded Glutamine will be absorbed faster and probably more efficiently than L-Glutamine in the Human digestive system.

BIBLIOGRAPHY

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