Optimum Conditions for Indoleacetic Acid Oxidase Extraction from Betula Leaves.

This report deals with total extraction and activation of soluble indoleacetic acid oxidase from Betula alleghaniensis leaves as affected by different buffers, varying pH, phenol binder, detergent, plus volume and time parameters. For all buffers and pH levels tested, only tris pH 8 gave a high activity. This result was not a pH effect, since a wide‐range, citrate‐phosphate buffer at pH 8 gave a very low activity. Addition of a neutral detergent, Triton X‐100, to all buffers gave considerable activity in every case. Most activity with Triton X‐100 occurred at pH 6 and least at pH 8 regardless of buffer composition. A phenol binder, polyvinylpyrollidone, increased activity also, but less than the detergent Triton X‐100. Both of these compounds in combination gave an additive effect and the highest measure of enzyme activity. Further increases in measurable indoleacetic acid oxidase activity were obtained by using the best combination of these factors to determine the optium tissue: buffer ratio and optimum soaking time. Increases in activity of 70 and 60%, respectively, were achieved. [ABSTRACT FROM AUTHOR]