4.4 Micro-organisms
Any plant growing in a natural environment is colonized with
micro-organisms, including bacteria, microalgae, yeasts and
moulds, so that micro-organisms detected on herbal raw
materials are not necessarily contaminants in the strictest sense.
The natural opportunistic microflora found on herbal raw
materials does not normally contain pathogenic species.
However, infestation of herbal raw materials or preparations
with pathogenic species (e.g., Enterobacteriae, Salmonellae, E.
coli) or potentially pathogenic levels of opportunistic species (e.
g., Bacillus spec.) may occur during any of the post-harvesting
stages, and microbiological quality needs to be assessed
routinely in both herbal raw materials and preparations. At
present, no legal limits have been set for herbal food supplements,
or for that matter, the majority of food items. Because
herbal food supplements and herbal medicines are similar with
respect to raw materials, preparation and finished forms, the
European Pharmacopoeia analytical methodology is fully
applicable. The microbial limits specified in the European
Pharmacopoeia47 are equally appropriate for herbal food
supplements and their attainment has been shown to be feasible
provided suitable germ-reducing processing steps are applied,
e.g. water vapour treatment.