Noni Seed Oil Topical Safety, Efficacy, and Potential Mechanisms of Action

Abstract

Background: Noni fruit and leaf juices were used to treat acne in Polynesian folk medicine. However, the potential benefit of noni seed oil (NSO) for human skin health is not as well known. Objective: The topical safety of NSO was evaluated in a repeat insult patch test with 49 adult volunteers. Comedogenicity was evaluated in 23 adolescent volunteers for four weeks. Anti-inflammatory activity was determined in-vitro with COX-2 and 5-LOX enzyme inhibition assays. Results: No reactions to NSO were observed in any of the volunteers. NSO also reduced the number of open and closed comedones in the comedogenicity test. NSO inhibited COX-2 and 5-LOX enzymes in a concentration dependent manner, but with COX-2 inhibition being more pronounced than 5-LOX. Conclusion: Noni seed oil is safe for topical use and is non-comedogenic. It also has potential anti-inflammatory activity, being a dual inhibitor of COX-2 and 5-LOX enzymes. These results indicate the potential utility of NSO for skin care applications, as well as warrant further investigation of efficacy in 5-LOX and COX-2 related pathophysiological conditions.