Azadirachta indica A. Juss (Neem) oil topical formulation with liquid crystals ensconcing depot water for anti-inflammatory, wound healing and anti-methicillin resistant Staphylococcus aureus activities

Abstract

Constituents of Azadirachta indica A. Juss (neem), have antimicrobial, cell proliferative, anti-inflammatory and wound healing properties. In the present study, neem seed oil is emulsified with an alkyl polyglucoside, Montanov 202™, to produce a topical applicant with liquid crystals that ensconce depot as confirmed by polarised microscopic, thermal and WXRD studies. Anti-inflammatory investigations by paw edema model, with this topical applicant in female Wistar rats showed inhibition of paw swelling by 39–60% over 30–180 min when compared to untreated animals. Similarly, wounds induced by incision procedure also had a significantly higher breaking strength (353.46 ± 7.95 g) when treated with this applicant after induction. Further, upon similar application, contraction was significantly higher (95% by 16th day) in wounds induced by excision procedures, with a re-epithelization period of 10.21 ± 2.31 days. Histopathology of these skin sections showed accelerated healing with development of dermis/epidermis and collagen with results that were synchronous to neomycin treated positive control rats. This applicant was also able to inhibit the growth of methicillin resistant S. aureus strains as shown by in vitro studies. It is inferred that the depot water ensconced in its liquid crystals synergistically supports the bioactivity of neem oil constituents to aid the healing of topical wounds as effectually as synthetic antibiotics. Simultaneous protection against MRSA induced wound infections serves as an additional advantage of this neem oil topical applicant.