Polylysine (Natural Preservatives)

What is Polylysine?

Ingredient similar to a natural substance created by advanced biotechnology

As an ingredient manufactured from natural substances using our biotechnology, Polylysine is a straight chain polyamino acid that connects 25 to 35 L-lysine residues, characterized by a peptide bond between the epsilon amino group and the carboxyl group in L-lysine, a kind of essential amino acid. Its safety is ensured by a variety of toxicity tests including a chronic test. It has also received a GRAS notice GRAS number from the US FDA.

Structure and Physicality

Characteristics

  • High safety
  • Helps inhibit proliferation of a wide range of microbes while working also as a surfactant.
  • Provides high heat stability and high water solubility.
  • Helps inhibit microbe proliferation in a wide pH range.

Effect

MIC of Polylysine against various microorganisms

Microorganism MIC(ppm) Medium
Gram-positive bacteria
Geobacillus stearothermophilus 5 6
Bacillus coagulans 10 6
Bacillus subtilis <3 7
Bacillus cereus 30 7
Staphylococcus aureus 12 4
Listeria monocytogenes 10 6
Lactobacillus brevis 10 3
Lactobacillus plantarum 5 3
Leuconostoc mesenteroides 50 3
Streptococcus lactis 100 3
Clostridium acetobutylicum 32 9
Clostridium sporogenes 200 6
Micrococcus luteus 16 6
Gram-negative bacteria
Escherichia coil 50 4,5
Salmonella typhimurium 16 4
Enterobacter aerogenes 8 4
Pseudomonas aeruginosa <3 4
Campylobacter jejuni 100 8
Yeasts
Saccharomyces cerevisiae 50 2
Zygosacchromyces rouxii 150 1
Candida acutus 6 2
Pichia anomala 150 2
Pichia menbranaefaciens <3 2
Rhodotorula lactosa 25 1
Sporobolomyces roseus <3 2
Phaffia rhodozyma 12 2
Molds
Aspergillus niger 250 1
Trichophyton mentagrophytes 60 1

Medium#

  1. Potato dextrose(pH 5.6)
  2. Malt Broth(pH5.0)
  3. Glucose malt broth(pH6.0)
  4. Nutrient broth(pH7.0)
  5. Deoxycholate broth(pH7.4)
  6. BHI(pH 7.0)
  7. Trypto-soya broth(pH7.3)
  8. Brucella broth(pH7.0)
  9. Thioglycollate medium without indicator:gluid(pH 7.1)

2. Effect of pH on the MIC

Tested bacteria MIC(mg/L) 6.0 7.0 8.0
5.0 6.0 7.0 8.0
Bacillus subtilis 3 3 3 3
Bacillus cereus 25 100 50 12.5
Escherichia coli 25 25 50 50
Staphylococcus aureus 12.5 25 12.5 ?6.3

3. Effect of heat treatment on the MIC

Treatment 50
Untreated 50
80oC, 60 min 50
100oC, 30 min 50
120oC, 20 min 50
Trichophyton mentagrophytes 60

Application