Development of skin whitening preparations from kaffir lime oil (Citrus hystrix)
Kaffir lime oil (Citrus hystrix L., Rutaceae) has been used in medications and cosmetics. The oil showed antioxidant and skin whitening effects . The main objective of this study was to develop topical whitening formulations from essential oil of C. hystrix grown in Thailand. Tyrosinase inhibition was used as an indicator of the whitening effect. The dopachrome microplate assay was used for determination of enzyme activity [2, 3]. The percentage of tyrosinase inhibition of fruit peel oil and leaf oil (0.25% w/v) was 54 and 55, respectively. The oil was extracted and analyzed by GC-FID and GC-MS. Topical formulations from the essential oil of C. hystrix were developed into two different dosage forms, i.e. cream and gel. The formulations were developed in terms of physicochemical properties and organoleptic feature. Skin irritation test in rabbits and human volunteers were performed. The results showed that both topical cream and gel formulations had no irritation to either rabbits or human volunteers. In addition, stability studies of the formulations were evaluated and the formulations were found to be physically and chemically stable over a period of 1 year at 4 and 25°C. In conclusion, this study demonstrated the strong potential of health products containing essential oil of C. hystrix in cosmetic application.
References: 1.Manosroi, A. et al. (2003), Proceedings in the 3rd World Congress on Medical and Aromatic Plants for Human Welfare. 2. Isao, K. et al. (1999), Planta Med. 65: 19–22. 3. Koichi, I. et al. (1995), Planta Med. 61: 425–428.