[curiouscat]

Is filtration a viable option to isolate a pure form of a metabolite like Hyaluronic Acid (HA) from the fermentation products of a baccilus?

I always assumed filtration cannot be used for such exacting bioseperations and thought chromatography was the typical seperation process. But I came across an article which seems to say that by a combination of "ultrafiltration, infiltration and depth filtration" a pure HA product can be obtained.

http://www.pharmaasia.com/2013/12/finding-an-alternate-source-bacillus-subtilis-in-the-production-of-hyaluronic-acid/

Is this typically possible? I was assuming that any baccilus, even if genetically modified, will create a diverse bunch of high MW products and having a filter with the exact pore size to obtain a pure product was not feasable?

What's the actual state-of-the-art?

[Arkcon]

Briefly, its not really true that living things excrete a wide variety of large molecules. They can be designed to excrete only one type, either by genetic engineering, or by nature.  As your reference mentions, the HA is contaminated with smaller molecules, but filtration helps with that.  Also, HA is a pure compound to begin with, the product is a polymer of a variety of subunit lengths.  It doesn't need to be purified more than that for the average application.