2-Hydroxyisocaproic acid (HICA) is a normal constituent of human plasma as well as an animal protein fermentation product of Lactobacillus plantarum. It is considered formed by transamination of leucine to 2-ketoisocaproic acid (KICA) followed by a reduction reaction of KICA to HICA.

According its amphipathic and hydrophobic properties, HICA can possess antimicrobial activity¹. M Sakko, et al. studied antimicrobial efficacy of HICA against a representative panel of clinically significant Gram-positive and Gram-negative human pathogenic bacteria.²

Based upon the comparisons of susceptibility testing of 18 bacterial isolates (comprising 8 clinicalisolates and 10 reference strains belonging to eight facultative aerobic and anaerobic bacterial species), HICA was most active against Staphylococcus aureus strains. A HICA concentration of 4.5 mg/mL causing >90% growth inhibition of Pseudomonas aeruginosa reference isolate and 79% growth inhibition of the clinical isolate, which showed HICA has a broad antibacterial effect, including bacteria resistant to multiple systemically used antimicrobials such as MRSA.² In other studies, HICA paste exerted superior activity against E. faecalis,³ which indicated that HICA have potential for root canal medication.

The results of compared the antibacterial activity of HICA with currently used root canal medicaments, support the long-term antibacterial activity of HICA and indicate its tolerance to clinically relevant concentrations of dentine and other inhibitors commonly present in the root canal system⁴.

Therefore, HICA is not just a natural support for ­muscle growth, but also could have potential as an interappointment medication in the treatment of root canal infections. We hope to get more clinical research and the literature reviewed to prove the activity and find new benefits of taking HICA.

References

[1] PK Hietala, HW Westermarck, M Jaarma, et al. Nutr Metab. 1979, 23, 227-234.

[2] M Sakko, L Tjäderhane, T Sorsa, et al. International Journal of Antimicrobial Agents. 2012, 39, 539-547.

[3] M Sakko, L Tjäderhane, T Sorsa, et al. International Endodontic Journal. 2016.

[4] M Sakko, L Tjäderhane, T Sorsa, et al. International Endodontic Journal. 2016, 49, 352–360.