Wednesday, 17 July 2013

Brevundimonas (Pseudomonas) diminuta - Sterile Filter challenging organism

Brevundimonas (Pseudomonas) diminuta - Sterile Filter Challenging Organism

Sterilizing grade filter is one that will produce a sterile effluent after being challenged by microorganisms at a challenge level of greater than or equal to 1x107/cm2 of effective filtration area.


Until the late 1960’s, 0.45 μm-rated membranes were considered “sterilizing grade” filters, and were used successfully in the sterilizing filtration of parenterals. In the mid-1960’s Dr. Frances Bowman observed a 0.45 μm “sterile-filtered” culture medium to be contaminated with a micro-organism, subsequently shown to penetrate 0.45 μm-rated membranes repeatedly in small numbers.


Brevundimonas diminuta is a standard organism for validation of sterilizing-grade membrane filters.

Brevundimonas diminuta (formerly known as Pseudomonas diminuta)  is a gram negative 0.5x1.0 -4.0 μm,motile rod with one polar flagellum.

1 comment: