DL-Histidine has been used to study the fouling behaviour of polyethersulfone ultrafiltration membranes made with different PVP (polyvinylpyrrolidone).

DL-Histidine is the mixed isomer of D- and L-histidine. DL-Histidine may be used to evaluate the efficiency of amino acid chiral ligand exchange media and systems and in running buffers for capillary electrophoresis.

L-Histidine is involved in the one-carbon unit metabolism. It is associated with protein methylation. L-Histidine is a part of hemoglobin structure and function. L-Histidine is a component of dipeptides with antioxidative property. Histidine serves as a precursor for the formation of histamine, which is associated with allergic responses. Urocanic acid, an immune response modulator in skin is also biosynthesised from histidine.