IA on effect of different pH on enzyme catalase (potato extract) on the rate of decomposition of H2O2 measured using a pressure sensor.
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The document describes an experiment investigating the effect of different pH levels on catalase activity using potato extract to decompose hydrogen peroxide (H2O2) into water and oxygen. A pressure sensor was utilized to measure the rate of oxygen production at various pH values (1, 4, 5, 7, 9) using specific reaction procedures. Results indicated that the enzymatic activity was optimal at neutral/alkaline pH, with measured rates showing significant variation across different conditions.
IA on effect of different pH on enzyme catalase (potato extract) on the rate of decomposition of H2O2 measured using a pressure sensor.
- 1. Centrifuge to spin down the extract Catalase extract (clear solution used) Potato, pressure sensor, H2O2 Diff pH buffer (1,4,5,7,9) were used. To investigate the optimum pH for catalase activity 5% (v/v) H2O2 used. Pressure sensor to measure O2 released. Reaction mechanism Procedure: 5g of potato added to 50ml water (10%) – centrifuge to collect extract 250ul catalase extract added to 1 ml of buffer of diff pH. 1 ml of mixture, added to 5ml of 5% H2O2 Rate was measured – change of pressure over time. Hydrogen peroxide decomposition – O2 production 2H2O2→ 2H2O + O2 Effect of diff pH on enzyme catalase (potato extract) on the rate of decomposition of H2O2 measured using a pressure sensor.
- 2. Negative control - only pH without enzyme catalase Positive control – only potato catalase without any pH buffer. Pressure increase - due to enzyme catalase, and not pH. pH Rate/kPas-1 1 0.01167 4 0.004171 5 0.01623 7 0.2128 9 0.1724 -ve control No change Seems like amylase from potato extract function well in neutral/alkaline medium Diff pH (1, 4, 5, 7, 9) were used Effect of diff pH on enzyme catalase (potato extract) on the rate of decomposition of H2O2 measured using a pressure sensor. 0 0.05 0.1 0.15 0.2 0.25 1 4 5 7 9 Rate of decomposition pH pH vs rate of decomposition
- 3. Method 1 Method 2 Time Time Volume Pressure • Rate = Δ vol O2 over time • Volume recorded • Rate = Δ pressure O2 over time • Pressure recorded Procedure 2H2O2 → O2 + 2H2O Rxn: H2O2 with diff (catalyst) measured using TWO diff methods • 2H2O2 → O2 + 2H2O (H2O2 limiting, KI excess) • Pipette 1ml 1.0M KI to 20ml of 1.5% H2O2 • Vol O2 released recorded at 1 min interval • Repeated using 3% H2O2 conc Time/m Vol O2 (H2O2 1.5%) Vol O2 (H2O2 3.0%) 0 0.0 0.0 1 8.5 14.0 2 15.0 26.5 3 21.0 34.0 4 26.0 39.0 Volume O2 Time 3 % 1.5 % Effect of diff pH on enzyme catalase (potato extract) on the rate of decomposition of H2O2 measured using a pressure sensor.
- 4. • 2H2O2 → O2 + 2H2O (H2O2 limiting, KI excess) • Pipette 1ml 1.0M KI to 20ml of 1.5% H2O2 • Pressure O2 released recorded at 1 min interval • Repeat using 3% H2O2 conc Method 1 Method 2 Time Time Volume Pressure • Rate = Δ vol O2 over time • Volume recorded • Rate = Δ pressure O2 over time • Pressure recorded Procedure 2H2O2 → O2 + 2H2O Time 3 % 1.5 % Time/m Pressure O2 (H2O2 1.5%) Pressure O2 (H2O2 3%) 0 101.3 101.3 1 102.4 103.4 2 103.5 105.6 3 110.3 115.2 4 113.5 118.2 Pressure O2 Rxn: H2O2 with diff (catalyst) measured using TWO diff methods Effect of diff pH on enzyme catalase (potato extract) on the rate of decomposition of H2O2 measured using a pressure sensor.