INTERFERENCE WITH THE DETERMINATION OF 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID BY VARIOUS PLANT-PROTEINS

The assay for 1-aminocyclopropane-1-carboxylic acid (ACC), the precursor of ethylene, is a widely used technique that is subject to decreased sensitivity unless interfering substances are removed. The work presented shows that sensitivity of the assay is decreased by protein, sulfhydryl reagents, and amines. Type and amount of protein present influenced sensitivity of the assay. Protein from soybeans decreased sensitivity more than protein from tomato. Interference with the assay also occurred with small molecules containing functional groups found in proteins; the interference did not, however, seem entirely related to the functional groups. Improved detection of ACC in the presence of interfering materials was accomplished by increasing the concentration of HgCl2 from 10 mmolL-1 to 50 mmolL-1. This observation suggests that the sensitivity of ACC determination may be improved by simply increasing the concentration of HgCl2 in the assay.