The Impact of Handling and Storage of Human Fecal Material on Bacterial Activity

Fecal material prepared from human stools is frequently used for the assessment of bacterial degradation of active pharmaceutical ingredients as relevant data are useful for evaluating the potential for colonic drug delivery. The impact of handling and storage of human fecal material on bacterial activity was assessed by evaluating the degradation characteristics of metronidazole and olsalazine. Multiple freeze (−70°C)-thaw cycles should be avoided. Incubation of frozen material for about 2 h in the anaerobic workstation ensures regeneration of the highest possible bacterial activity. Material could be stored at −70°C for at least 12 months.