Thermo Scientific Limited has introduced a safer, more effective alternative to GVPC supplement (recommended in ISO11731 - Water Quality) for the detection of Legionella species. New Thermo Scientific Legionella (GVPN) Selective Supplement has the same formulation as GVPC supplement, except that the toxic component, cycloheximide, has been replaced by the safer natamycin.
(Legionella bozmanii growing on Thermo Scientific Legionella BCYE + GVPN Medium showing fluorescence under UV light)
Cycloheximide was added to the original formulation to suppress the growth of fungi. Natamycin is also an effective anti-fungal agent, commonly used in the food industry to control the growth of undesirable moulds on the surface of cheese. Natamycin is less toxic than cycloheximide, making it safer to use in culture procedures, and has been shown to be a suitable substitute in a range of agar media (ref 1).
In trials, GVPN was shown to recover all Legionella species at least as well as GVPC (ref 2). Furthermore, there was evidence that the recovery of autofluorescent strains and the inhibition of competitor flora were enhanced using GVPN.
Thermo Scientific Legionella (GVPN) Selective Supplement (SR0215E) is intended for use with Legionella CYE Agar Base (CM0655) and BCYE Growth Supplement (SR0110) for the detection and enumeration of Legionella species from environmental water samples.
References: 1. Pedersen, J.C. (1992) App and Environ Microbiol 58(3):1064-1066 2. Thermo Scientific Limited, Poster presentation (folio LT0848A)
For further information about Thermo Scientific Legionella (GVPN) Selective Supplement and other products in the Thermo Scientific range for the detection of Legionella species