An investigation of the antimicrobial and anti-inflammatory activities of crocodile oil

Abstract

Ethnopharmacological relevance: Crocodile oil has been used by traditional practitioners world-wide to treat microbial infections and inflammatory conditions. However, the scientific rationale behind its use is not completely understood. This study provides an updated fatty acid profile and novel scientific evidence of the antimicrobial and anti-inflammatory properties of crocodile oil, obtained from the Nile crocodile (Crocodylus niloticus), justifying its use by traditional healers.

Materials and methods: The fatty acid content of the oil was determined by gas chromatography and the major fatty acids were identified. A microplate method was used to assess activity of the oil against Staphylococcus aureus, Klebsiella pneumoniae and Candida albicans. The anti-inflammatory activity of the oil was assessed by oral administration and topical application, utilising a mouse model of acute croton oil-induced contact dermatitis.

Results: Sixteen fatty acids were identified with oleic, palmitic and linoleic acid being the major components of the oil. The optimal activity of the oil against the bacteria and fungus was obtained with 15% and 6% (w/v) oil respectively. No significant selectivity was observed against the bacterial species, but Candida albicans was more susceptible. The anti-inflammatory assays showed optimal activity at 3h after the oral administration of oil (60.8±5.5%) and at 12h after topical application (57.5±5.9%). This suggested a short duration of action when the oil was orally administered, and a longer duration of action when it was topically applied.

Conclusions: Subsequent studies may be directed towards the investigation of the mechanisms of action of the antimicrobial and anti-inflammatory activities of crocodile oil and its fatty acids.