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Oral Supplementation with a Combination of Kyowa Hakko’s L-Citrulline and L-Arginine Can Rapidly Increase Nitric Oxide Bioavailability

April 23, 2015 New York, NY

Study Shows Promise in Human Applications for Regulating Cardio Function*  

New York City, NY (PRWEB) April 24, 2015 – A combination of L-Citrulline and L-Arginine oral supplementation caused a more rapid increase in plasma L-Arginine levels and marked enhancement of Nitric Oxide bioavailability, including plasma cGMP (Cyclic guanosine monophosphate) concentrations, than with dosage with the single amino acids.

The study, published in Biochemical and Biophysical Research Communications, set out to determine the short-term action of oral doses of L-Citrulline and L-Arginine on nitric oxide production. Results showed that the combined supplementation was significantly more effective than single doses of arginine.1

For more information about the BBRC-published study, visit

  1. Masahiko Morita, Toshio Hayashi, Masayuki Ochiai, Morihiko Maeda, Tomoe Yamaguchi, Koichiro Ina, Masafumi Kuzuya, Oral supplementation with a combination of l-citrulline and l-arginine rapidly increases plasma l-arginine concentration and enhances NO bioavailability, Biochemical and Biophysical Research Communications, Volume 454, Issue 1, 7 November 2014, Pages 53-57, ISSN 0006-291X,


About Kyowa Hakko’s L-Citrulline

L-Citrulline is an amino acid that plays an important role in nitric oxide metabolism and regulation. L-Citrulline is converted to L-Arginine in the body, leading to sustained increases in both L-Arginine and nitric oxide. An ingredient with application in the areas of heart health and sports nutrition, L-Citrulline is preservative-free, allergen-free, and contains no artificial flavors or colors. It’s non-hygroscopic, highly stable, and mild taste makes it suitable for use in a variety of formulations. This pure, vegetarian ingredient is also self-affirmed GRAS. Manufactured in the U.S. using a proprietary fermentation process, L-Citrulline is an ultra-pure amino acid that carries the Kyowa Quality logo, ensuring the ingredient is backed by our commitment to the highest manufacturing standards.

About Kyowa Hakko USA

Kyowa Hakko USA is the North American sales office for Kyowa Hakko Bio Co. Ltd. (Kyowa Hakko Bio), an international health ingredients manufacturer and world leader in the development, manufacturing and marketing of pharmaceuticals, nutraceuticals and food products. Kyowa Hakko Bio is the maker of branded ingredients including Cognizin® Citicoline, Lumistor® L-Hydroxyproline, Pantesin® Pantethine, Setria® Glutathione, as well as Sustamine® L-Alanyl-L-Glutamine. For more information visit

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