Grapefruit Extract (ream: Effects on Melanin and Skin Naveed Akhtar, GuLfishan and Mahmood Ahmed The Islaima University of Bahawalpur, Bahawalpur, Pakistan Nazar M. Ranjha BI University, Multan, Pakistan Ahmad Mahmood University of the Punjab, Lahore, Pakistan KEY WORDS: ABSTRACT: grapefruit extract, stability, emulsion, melanin, erythema The current work aimed to formulate a stable wlo emulsion containing grapefruit extract by entrapping the extract in the inner aqueous phase. Thefinal formula was found to have skin-whitening, moisturizing, cleansing and antiwrinkle effects, among others. I~ E mulsions are thermodynamically unstable systems defined as micro- scopic dispersions Qf liquid droplets / contained within another liquid, with a diameter ranging from 0.5 Jl.I11 to 100 Jl.I11.1 Emulsions usually consist of mixtures of an aqueous phase with vanous oils or waxes. The liquid that is broken up into droplets is termed the internal or disperse phase, whereas liquid surrounding the droplets is known as the external or con- tinuous phase. Both phases are stabilized by a third component, the surfactant.2 The two most familiar types of emul- sions are readily distinguished as o/w and w/o.3The majority of skin care products and a sign,ificant percentage of toiletry products are emulsions.4 The basic components of these formulations are emulsifiers, emollients and consistency' enhancers.5 Additional value can be given to these formulations by including active ingredients with specific cosmetic or dermatological effects.4 Particularly advantageous cosmetic emulsion prepa- rations are obtained when antioxidants are used as active ingredients.6 Based on a perceived safety ben- efit, the worldwide trend toward using natural additives has spurred interest in Vol. 123, No. 1jJanuary 2008 natural antioxidants found in plants.7 Extract from grapefruit is rich in natural antioxidantsSand providessome cosmetic benefits for the skin such as reduction in skin melanin, increase in skin moisture and antiwrinkle effects? The best natural antioxidants present in grapefruit extract are ascorbic acid or vitamin C,9 flavonoids,1O beta carotene and lycopene.1I Thus, the current work aimed to formulate a stable w/o emulsion containing grapefruit extract by entrapping the extract in the inner aqueous phase. Testswere performed on sample formulations to measure their , effects on different physiological char- acteristics such as melanin, erythema, moisture, sebum, pH and TEWL. Materials Paraffin oil was used in the oily phase of a test formulation containing 1% grapefruit extract, as well as in the control (see Formula 1). Paraffin oil is a synthetic that is often preferred because of its benefits including being nontoxic and nonirritant to skin, as well as its ability to form an elegant white emulsion. It is a mixture of refined liquid saturated aliphatic (C14-CIS) and cyclic hydrocarbons obtained from petroleum.12 In addition to the paraffin, cetyl PEG/PPG-IO/1 dim ethic one" was chosen as the lipophilic emulsifier to form a w/o emulsion in both the test formulation and the control.13 Beeswax was incorporated in both formulas to increase the consistency a Abil-EM 90 (INCI: Cetyl PEG/PPG-lO/l dimethicone) is a product of Evonik. FormuLa 1. ControLandtest emuLsionsusedin the describedstudy OilPhase Paraffinoil CetylPEGjPPG-I0jldimethicone (Abil-EM90, Evonik) Beeswax Aqueous ohase Grapefruit extract Glycerin Water (aqua) Citricacid 1.00 qs to 100.00 qs to 100.00 Controlformula Test formula 20.00% wjw 20.00% wjw 4.00 4.00 4.00 4.00 1.00 (concentrated) 1.00 qs to 100.00 qs to 100.00 www.CosmeticsandToiletries.com Cosmetics & Toiletries" magazineI 55