DESCRIPTION
What is Plant Preservative Mixture “Affiplant PPM” ?
Plant Preservation Mixture (PPM) is a robust broad-spectrum biocide formulated for use in plant tissue culture. PPM targets bacteria and fungi in plant tissue culture growth media as well as contaminated tissue. It affects key enzymes in the Krebs cycle and in the Electron Transport Chain.
Depending on the dose and the level of contamination, PPM is a biocidal component in plant culture medium. In addition, it may also function as a biostatic compound as a preventative measure. When diluted with plant growth media it is effective as a microbiocide (i.e. bactericide and fungicide) against non-human health pathogenic organisms component of liquid or semi-solid plant culture media.
Affiplant PPM is effective for most seed baring plants – angiosperm, as well as gymnosperm,- however, it is not recommended for use in ferns, mosses, algae and aquatic plants. Optimization may be required to maximize potency. While PPM is an excellent tool in the prevention and elimination of culture contamination it is not a substitute for asceptic laboratory techniques and appropriate air handling systems are recommended.
Mechanism of Action
Affiplant PPM™ is a dual-mode preservative and biocide targeting both bacteria and fungi, including spore-forming species.
It functions by:
- Penetrating microbial cell walls and inhibiting key enzymes in the citric acid cycle and electron transport chain.
- Blocking the uptake of monosaccharides and amino acids, limiting microbial nutrient assimilation.
- Maintaining thermal stability during autoclaving, ensuring consistent protection throughout the medium’s lifespan.
Affiplant PPM™ requires a specific molecular-to-microbe ratio; thus, culture density and explant volume must allow adequate diffusion of the compound.
Application Procedures and Benefits
Affiplant PPM™ simplifies tissue culture workflow by minimizing sterile-hood dependency and reducing labor time.
Media Preparation :
- Add 0.5–2.0 mL/L of PPM™ to media before or after autoclaving.
- Suitable for both agar and liquid formulations.
- For protein-rich media (> 200 mg/L amino acids), sterile filtration with PPM™ is recommended.
Aseptic Workflow Simplification :
- Dispensing of media containing PPM™ can occur outside a Laminar Flow Hood (LFH) under clean conditions.
- Forceps and scalpels can be sanitized with 70 % ethanol rather than flame sterilization.
- Short-term bench work (< 1 hour) outside LFH is possible without significant contamination risk.
Storage Conditions :
- PPM™ is slightly acidic (pH ≈ 3.8) and should be stored at 4 °C.
- The product remains active after multiple autoclave cycles, supporting sustainable lab operations.
