effects of zinc, sodium and potassium metal ions on ammonium fraction of acid phosphatase of orange fruit

backgrounds and aims: the purpose of this study was to examine the effects of potassium, sodium and zinc metal ions on ammonium sulfate fraction of acid phosphatase activity of orange fruit. materials and methods: acid phosphatase was extracted and purified from orange fruit and then various samples as well as a control sample were prepared in vitro. in addition to substrates, ions of potassium, sodium and zinc were added to each sample and then, acid phosphatase activity of each sample was read by spectrophotometer in the determined wavelength. results and conclusions: zinc, sodium and potassium ions can increase activity of acid phosphatase up to 87.76%, 63.53% and 18.12%, respectively. the results of this study revealed that all three ions of zinc, sodium and potassium can increase acid phosphatase activity.