What is Plant Preservative Blend (PPM)?

Plant Preservative Mixture (PPM), is a broad-spectrum biocide for plant tissue culture. PPM ™ is the ultimate solution to the endless fight against airborne, waterborne and endogenous microbial contamination.


PPM or Plant Prreservative Mixture is a thermostable preservative/biocide that can be used to effectively prevent or reduce microbial contamination in plant tissue culture. In optimal dosages, PPM ™, which stands for Plant Preservative Mixture ™, is an extremely effective preservative/biocide but does not alter in vitro seed germination, callus proliferation, and callus regeneration.

PPM ™ prevents bacterial and fungal spore germination. It is heat stable and therefore can be autoclaved with the medium. PPM ™ can and should be used as a standard ingredient in plant tissue culture media, and it is also substantially less expensive than commonly used antibiotics.

While PPM ™ was primarily designed to inhibit air pollution, water pollution, and pollution introduced by human contact, it can also, in many cases, be used to reduce endogenous pollution. Despite the stricter use of sterile techniques, contamination of plant cell technology and tissue cultures remains a persistent problem that can result in losses ranging from a small number of cultures to the loss of entire batches.

Mechanism of action

PPM ™ is a broad-spectrum preservative and biocide, which kills bacteria and fungi cells, prevents spore germination, and in higher concentrations, it can eliminate the endogenous contamination of explants. It is heat stable and therefore can autoclave.  Our data indicate that PPM ™ can also inhibit the transport of monosaccharides and amino acids from the medium in fungal or bacterial cells.

As with any biocide, a critical ratio of PPM ™ molecules per microbial cell is required. to eliminate bacteria and fungi. Note that a given volume of PPM ™ doses has a constant number of PPM ™ molecules, while the number of spores introduced into tissue culture through endogenous contamination is highly varied.

Advantages of PPM over antibiotics

  • PPM ™ is broad-based and effective against fungi.
  •  PPM ™ is less expensive than antibiotics, making it affordable for routine and extensive use.
  •  Since PPM ™ targets and inhibits multiple enzymes, the formation of resistant mutants towards PPM ™ is highly unlikely.
  • PPM ™ is heat stable and can generally be autoclaved with medium


PPM ™ will definitely make work easier in any plant tissue laboratory and should significantly increase the productivity of technicians and laboratories. However, the conditions in each laboratory may vary and this could influence the effectiveness of PPM ™. It is recommended that personnel follow the above guidelines to maximize the effectiveness of PPM ™ for a specific laboratory and particular applications. Test results show that:

  • PPM ™ is effective against air and water pollution and contaminants introduced by human contact.
  • If used correctly, PPM ™ will release seeds or explants of endogenous substances contamination.
  • At the recommended doses (0.5–2 ml l – 1), PPM ™ does not damage the seed in vitro germination, callus proliferation, callus regeneration, or axillary induction of adventitious buds.
  •  The formulation of certain concentrations of PPM and their use in tissue culture to preventing or eliminating microbial contamination is protected by US Patent No. 5,750,402. It is also patent pending in many countries around the world.

Safe processes

Security issues. PPM ™ is not toxic; however, inhalation and skin contact, and eyes should be avoided as it is an acid. May be irritating to the skin, eyes, nose, and throat. As a precaution, we recommend that

  • users wear gloves and splash goggles;
  • users avoid contact with skin and eyes;
  • users avoid inhalation;
  • adequate and adequate ventilation is used;
  • the material must not be applied by spraying except with directed flow, positive pressure ventilation, and protective gear.

30 ml of PPM