25 May 2023 0 9K Report
  • Peroxidase Activity Assay: Homogenize a known amount of fresh fruit tissue in a phosphate buffer (pH 7.0) using a chilled mortar and pestle. Centrifuge the homogenate at a low temperature (4°C) to remove cellular debris. Prepare a reaction mixture containing the supernatant, hydrogen peroxide (H2O2), and a suitable peroxidase substrate (e.g., guaiacol). Measure the change in absorbance at a specific wavelength (e.g., 470 nm) over time using a spectrophotometer. The increase in absorbance indicates peroxidase activity.
  • Polyphenol Oxidase Activity Assay: Prepare a fresh fruit tissue extract by homogenizing the sample in a phosphate buffer (pH 6.5) containing a reducing agent (e.g., ascorbic acid). Transfer the extract to a cuvette and equilibrate it at a specific temperature (e.g., 25°C) in a spectrophotometer. Start the reaction by adding a suitable polyphenol substrate (e.g., catechol) and monitor the change in absorbance at a specific wavelength (e.g., 420 nm) over time. The increase in absorbance indicates polyphenol oxidase activity.
  • Catalase Activity Assay: Prepare a fresh fruit tissue extract by homogenizing the sample in a phosphate buffer (pH 7.0). Transfer the extract to a cuvette and equilibrate it at a specific temperature (e.g., 25°C) in a spectrophotometer. Start the reaction by adding a known concentration of hydrogen peroxide (H2O2) and monitor the decrease in absorbance at a specific wavelength (e.g., 240 nm) over time. The decrease in absorbance indicates catalase activity. -Are these three valid???????????

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