Bacterial and fungal contaminations represent the greatest threat to the cell culture system for the scientists in bio-research as well as for bioproduct manufacturers. It can lead to lose cell lines, to product unsafe biological drugs which is very expensive both in time and loss of materials (5,8). The potential sources of such a contamination are numerous (3,4,5):

• The external environment : air, water, surfaces in the cell culture room
  • The unfiltered air of the cell culture room can carry molds (Penicillium, Aspergillus, ...) (1,2), yeasts and bacteria (Staphylococcus sp.) on the work surfaces, in the laminar flow hood and in the incubators (5).
  • The water used for rinsing supplies or used in the water bath to warm bottles of media is one of the principle source of contamination by Pseudomonas sp. (6), Sphingomonas sp., Acinetobacter sp., Aeromonas sp. ...
• The supplies :
  • The equipment (laminar flow hoods, incubators..) and all materials going into and out of the laminar flow hood must be regularly disinfected between experiments : each pipetting or other liquid handling can generate aerosols of potentially infectious droplets flying to survive for days on all contacted surfaces (5,8).
  • The reagents such as sera which are one source of contamination by mycoplasmas (5,7).
  • Incoming cell lines which are initially infected (4,5,8).
• The laboratory personnel (5,8) :
  Human can generate infectious airborne particles and/or aerosols by talking, coughing or sneezing . Dust from skin, hair, or clothing can contaminate all contacted surfaces with bacteria from the skin flora.
  

As the sources of microbial contamination are numerous, the type of microbes able to infect cell culture are also many. In front of such a various threat, there is a solution called Normocin™.

Normocin™ is a unique antibiotic solution specially developed to prevent cell contamination from both Gram+, Gram- bacteria, mycoplasmas, yeasts and filamentous fungi in small or large animal cell cultures. Normocin™ is the first innovative formulation both:

• Able to replace penicillin/streptomycin/ amphotericin B preparations, and
• Able to prevent Mycoplasma contamination.

Normocin™ contains three compounds: two of them act on two different prokaryotic targets and the third compound eradicates fungi (yeasts and molds) by interfering with the cell membrane. The two antibiotic compounds present a broader antibacterial spectrum than penicillin / streptomycin mixtures. As the active concentration of Normocin™ (100 µg/ml) displays no toxicity to cell line, it is recommended to use it as a “routine addition” to cell culture media to prevent bacterial and fungal contamination.