Nisin is a natural preservative used in the biopreservation of food. NISIN is a natural additive obtained from the fermentation of a strain of Lactococcus lactis subsp. lactis (non-GMO). Nisin is a natural bactericide, approved by the EU (food additive number E-234), active against a large number of gram-positive bacteria, especially spore forming bacteria such as Clostridium spores, Staphylococcus aureus, Listeria monocytogenes, Bacillus subtilis, etc. NISIN is not active against gram-negative bacteria, yeasts or moulds.