L-Citrulline is one of the three dietary amino acids in the urea cycle, alongside L-arginine and L-ornithine. It’s used as a cardiovascular health and sports performance nutritional supplement. 

Supplementing with L-citrulline has been shown to increase both ornithine and arginine plasma content, which means that L-citrulline supplementation improves the ammonia recycling process and nitric oxide metabolism. By boosting nitric oxide production in the body it improves blood flow as a vasodilator and induces greater flexibility in the walls of blood cells. These functions support improved physical endurance, lower blood pressure, and reduced erectile dysfunction.

After supplementation, L-citrulline is converted into arginine in the kidneys. Supplemental L-arginine provides a spike of L-arginine in plasma, while supplemental L-citrulline increases arginine plasma levels over a longer period of time. In addition, L-arginine and L-ornithine are subject to reduced absorption when supplemented in doses of 10g or more, which can result in diarrhea. L-Citrulline does not have this side-effect, and since it increases plasma levels of all three amino acids, it is generally preferred as a supplement over L-arginine. As it is better absorbed than arginine it is a more bioavailable source. 

Water-soluble L-citrulline passes through the digestive system quickly, with some portion absorbed and the remainder evacuated. Prior research on other water-soluble active ingredients indicate that a sustained release form increases systemic exposure and is therefore more bioavailable. Sustained release would enhance the naturally occurring improved bioavailability in the conversion to arginine. 

Microactive Citrulline Benefits:

MicroActive® L-Citrulline increases absorption by reducing the particle size less than 10 microns thereby promoting more efficient transport through the digestive track and cell walls. In addition, the proprietary mix of polymers in MicroActive® L-Citrulline slows the release rate allowing for absorption over a longer time period. Evidence supports the claim that this combination of greater absorption and sustained release creates a more uniform absorption from subject-to-subject, improving the probability that all consumers will benefit from the active.

L-Citrulline is a safe, naturally occurring essential nutrient found in a number of protein food sources, including milk, legumes, meats, and fish. MicroActive® L-Citruline is produced using all GRAS approved ingredients having been subjected to numerous safety studies including acute toxicity in both humans and animals.

Additional Microactive Citrulline Benefits:

Microactive® L-Citrulline is a free flowing powder containing 60% of the active. It can be formulated with other ingredients and has a sustained release of 10 hours. The below figure presents the comparison of dissolution profile of citrulline at 200mg dose. The 98% citrulline powder showed 100% release of the dose by 1 hour. The MicroActive® formula showed a sustained release from 35% at 1 hour to 91% over a period of 10 hours.

MicroActive® L-Citrulline Product Specifications:

• 60% L-citrulline concentration

• L-citrulline in a sustained release matrix

• White powder

• Two year shelf life

• Suitable for hard gelatin capsules