Preparation and Characterization of Nano-Lipopeptide Biosurfactant Hydrogel and Evaluation of Wound-Healing Properties

Nano-formulation of biosurfactant can enhance the absorption of active material. The aim of this study was to produce a nano-lipopeptide biosurfactant (NLPB) formulation from lipopeptide biosurfactant (LPB) produced by Acinetobacter junii, which was previously isolated from oil exploration areas. Besides, the wound-healing activity of the obtained NLPB formulation was also determined. The NLPB was prepared using reflux method with microwave irradiation and loaded on carbomer hydrogel formulation. The physicochemical and structural properties of NLPB formulation were evaluated using dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). For determination of in vivo wound-healing activity, the prepared formulation was administered to 24 rats (previously wounded in depilated thoracic region) which were randomly distributed into six groups. The examined parameters for evaluation of the wound-healing activity were percentage wound contraction and histopathological study of regenerated tissue by hematoxylin and eosin (H&E) and trichrome staining. The size of the LPB was decreased to 80 nm by reflux method. The NLPB formulation had the most stable physicochemical properties. For the in vivo test, the concentration of 2 mg/ml was selected as the best formulation. In vivo test on rats also showed the best efficacy of the formulation on wound closure and healing. NLPB has the same physical properties as the LPB. Moreover, by decreasing the size of LPB, the wound-healing property of the LPB increased.