I have often used 0.02% sodium azide as a preservative for long-term storage of aqueous Sephadex suspensions. Sephadex is a carbohydrate material. Sodium azide inhibits cytochrome oxidase (so be careful with it because it is toxic), preventing the growth of bacteria and mold.

Maybe PERSTERIL is the inhibitor of choice. Please see

http://www.eurosarm.cz/web/structure/persteril-kyselina-peroctova-44.html?lang=en

This sterilization solution PERSTERIL is used among others in food industry, hospitals and for many other pursposes. Its big advantage is that it is very efficient in killing microbes (bacteria, yeast, fungi, even bacterial spores) but it is degraded in short time after use so no leftovers which can influence enzymic hydrolyzes are formed.

REgards

Vit 

Dear Arthur, 

As you mentioned the biomass you  do not want to sterilized.   So you can try quaternary ammonium salts, which are commonly used as antimicrobial  agent and disinfectants in food industry  for  examples are benzalkonium chloride, benzethonium chloride, methylbenzethonium chloride, cetalkonium chloride, cetylpyridinium chloride, cetrimonium, cetrimide, dofanium chloride, tetraethylammonium bromide, didecyldimethylammonium chloride and domiphen bromide.

Before using on large scale , first you need to test  the enzyme activity remain same in presence of  quaternary ammonium salts.

Hope this information will be helpful.

Regards,

Atul

There are several contamination interferences and preventative means that NREL (https://www.nrel.gov/docs/fy15osti/63351.pdf ) have highlighted for enzymatic saccharification of lignocellulosic biomass, please read section 5. Interferences, point 5.9 and 5.10 in attached file. Hope this is of help. Cheers.