PPM™ (Plant Preservative Mixture) is a heat stable preservative/biocide that, based on the dose, effectively prevents or reduces microbial contamination in plant tissue culture. At optimum doses, PPM™, does not impair in vitro seed germination, callus proliferation or callus regeneration.

Despite the most stringent use of sterile techniques and aseptic conditions, the contamination of plant cell and plant tissue cultures remain a persistent problem. PPM™ prevents the germination of both bacteria and fungi spores. Because it's heat stable, it can be autoclaved with media.

PPM™ can be used as a standard ingredient in plant tissue culture media. PPM is less expensive than antibiotics and can prevent fungal contamination simultaneously. PPM is both biostatic and biocidal. In addition to inhibiting airborne, waterborne and human contact contamination, it also can be used to reduce endogenous contamination.

The principal PCT scientist involved in the development of the PPM™ application is Dr. Assaf Guri. Dr. Assaf Guri holds degrees in genetics, applied genetics and plant breeding from the Hebrew University in Jerusalem and Michigan State University in the US. Before joining Plant Cell Technology, Inc., Assaf worked with the Volcani Agricultural Research Center in Israel, Michigan State University in East Lansing, Michigan and DNAP in New Jersey.