can be used for wound dressing purposes, and also this can protect the prosthetic

parts from secondary infection as well as from the biofilm formation. These

nanofibres are formed by adding surfactin and PVA solutions and following gravity

electrospinning (Ahire et al. 2017).

26.7

Mechanism for Synthesis of NP-Associated Lipopeptide

(NP-LP Particles)

Lipopeptide class of biosurfactants have been reported in NP synthesis. Surfactants

are commonly used as stabilizing agents in the synthesis of gold and silver NPs. In a

common procedure (Fig. 26.1), NP synthesis involves reduction of the aqueous

AuCl4 using NaBH4 in the presence of surfactin obtained from B. subtilis. Foam

fractionation was done to recover surfactin from the culture supernatant which was

further added to pale yellow colour chloroaurate solution that turned red-purple. This

indicated the change in metal oxidation state and the formation of gold NPs. The NPs

can be synthesized at a pH of varying range of 5–9 at 4 ^C.

Lipopeptides obtained in B. subtilis

Lipopeptide obtained using foam fraction

Added to Chloroaurate solution

Reduction of Aq.Aucl4

Used in reduction process

presence of Lps (surfactin)

by NaBH4 in the

Change in colour upon

addition of LPs indicated

the formation of NPs-LPs

particles

Fig. 26.1 General process for development of NP-LP particles

26

Nanoparticle-Associated Lipopeptides: A New Class of Antimicrobials

489