Common Food Additives Inhibit Carbonic Anhydrase Activity

Few studies about the effects of food additives on human enzymes exist. The effects of 20 food additives (12 colorants, 2 antioxidants, 3 sweeteners, 2 preservatives, and 1 acidity regulator) on bovine carbonic anhydrase (bCA) and especially human isoenzymes hCAI and hCAII isoenzyme, a highly vital enzyme, were studied for the first time. All the additives showed inhibition on human CA isoenzymes with IC₅₀ values in 5-5998 μM range. The higher inhibitions were detected in the colorants, Erythrosine B showing the highest inhibition (IC_50(bCA): 11 μM, IC_50(hCAI): 19 μM and IC_50(hCAII): 5 μM) at levels comparable with standard CA inhibitor sulfanilamide, while sweeteners showed low inhibition. BHT, a synthetic antioxidant, had higher inhibition compared to ascorbic acid. According to ADMET results, when the pharmacokinetic properties of the additives are considered, the only molecule with high gastrointestinal absorption is curcumin. The findings suggest that the health concerns caused by excessive consumption of foods containing additives may be related to CA inhibition. Food additive alternatives with no/lower CA inhibition should be sought for. Besides, Erythrosine B derivatives deserve investigation for new CA inhibitors.