Molecular weight and pH aspects of the efficacy of oligochitosan against methicillin-resistant Staphylococcus aureus (MRSA)

作者：Kulikov Sergey; Tikhonov Vladimir^*; Blagodatskikh Inesa; Bezrodnykh Evgeniya; Lopatin Sergey; Khairullin Ruslan; Philippova Yulia; Abramchuk Sergey

来源：Carbohydrate Polymers, 2012, 87(1): 545-550.

DOI：10.1016/j.carbpol.2011.08.017

• Oligochitosan
• Antibacterial activity
• Staphylococcus aureus
• MRSA
• Self-aggregation

Oligochitosan samples varying in molecular weight (M(w)) and having narrow polyclispersities were prepared by means of depolymerization of chitosan in hydrochloric acid, and their antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) was measured at pH values 5.5-8.0. The antibacterial testing of oligochitosans obtained showed that oligochitosans having M(w) in the range of 0.73-20.0 kDa could be used both at slightly acidic and neutral pH values, and that the activity against MRSA remained moderate for oligochitosan samples having M(w) about 3-5 kDa even at slightly basic pH values. The self-assembling behavior of oligochitosan macromolecules in the dilute solution at various pH values as a function of chain length was investigated. At first it was shown that oligochitosans formed supramolecular aggregates in dilute solutions below the critical pH value 6.5. Despite the aggregation phenomenon, the formation of nano-sized aggregates did not prevent oligochitosan from demonstrating the bactiostatic activity.

• 出版日期2012-1-4