Microbial Enzyme | Cellulase | Laccase | Xylanase | Pectinase | Peroxidase
Peroxidase – A Catalytic Enzyme for Enhanced Agarwood Resin Formation
Peroxidase enzymes are oxidative catalysts that use hydrogen peroxide (H₂O₂) to oxidize phenolic compounds, playing a crucial role in lignin polymerization, stress signaling, and defense response activation in plants. In Aquilaria malaccensis, peroxidase activity is naturally elevated during wounding or fungal infection and is associated with oleoresin biosynthesis.
Scientific Overview
- Enzyme Class: EC 1.11.1.7 (Class III Plant Peroxidases)
- Substrates: Phenolic acids (e.g., coniferyl alcohol, ferulic acid), lignin monomers
- Cofactor: H₂O₂ (hydrogen peroxide)
- Sources:
- Plants (Aquilaria, Horseradish)
- Fungi (Coprinus cinereus)
- Commercial (Horseradish Peroxidase, HRP)
Role in Agarwood Induction
| Function | Effect |
|---|---|
| Lignin Polymerization | Enhances rigidification and darkening of infected wood |
| Phenolic Oxidation | Promotes formation of chromogenic resin precursors |
| Stress Amplifier | Boosts host oxidative burst in response to fungal/abiotic stress |
| Synergy with Laccase | Dual oxidation of monolignols → faster and darker resin streaks |
Use in Inoculant Enhancement
Peroxidase can be used:
- As a pre-treatment enzyme
- In co-inoculation with fungi or abiotic inducers (FeCl₃, salicylic acid)
- In BarIno™-style formulations for boosting oxidative stress responses
Field Application Protocol
Peroxidase Pre-Inoculation Formula
| Component | Amount per Tree |
|---|---|
| Peroxidase (HRP) | 5–10 mg (≥100 U/mg activity) |
| Hydrogen peroxide (H₂O₂, 0.1%) | 10 mL |
| Sterile buffer (pH 5.5) | Adjust volume to 20 mL |
Application:
- Drill 3–5 holes (2–3 cm deep) in the trunk
- Inject 2–3 mL of peroxidase solution per hole
- Wait 6–8 hours
- Then inject fungal inoculant or BarIno™ product
- Seal holes with wax or parafilm
Expected Benefits
| Feature | Impact |
|---|---|
| Increased oxidative stress | Triggers plant defense metabolites |
| Enhanced resin polymerization | Leads to darker, denser agarwood |
| Faster onset | Visible wood discoloration in 2–4 weeks |
| Improved oil profile | More complex sesquiterpenoid content |