EMULGEL FORMULATION AND IN VITRO AND IN VIVO ASSESSMENT 9 varying speeds, from 0.5 to 50 rpm. The data have shown shear thinning/pseudoplastic behavior at room temperature where there is a decrease in viscosity by increasing the shear rate, which is a desirable property for topical preparations to facilitate the spreading of the product during application. A photomicrograph of the emulgel is shown in Figure 3. SPF ASSESSMENT RESU LT Several vegetable o ils, such as almond, avocado, coconut, cottonseed, olive, peanut, sesame, and soya bean, have been reported to have UV fi lters. In addition, when applied to the skin, these oils are easily absorbed and show great spreadability (8,28). Accordingly, this emulgel was assessed for its SPF value, which may be considered as an added value to its original cosmetic and organoleptic properties. The LG emulgel recorded a moder- ate SPF which is close to 5.5. Therefore, this cosmeceutical property, beside the reported anti- infl ammation activity of the LG oil, makes the daily application of this emulgel advisable because it may provide reasonable protection against the harmful effect UV light. IN VIVO STUDIES Unl ike the registra tion of a pharmaceutical product, the registration of a cosmetic product does not require specifi c tests to demonstrate the safety and effi cacy of individual products or ingredients. In addition, the law does not oblige cosmetic companies to share their safety information with regulatory bodies such as the Food and Drug Administration (FDA). Accordingly, cosmetic fi rms and individuals who produce or market these products have the legal responsibility to ensure the safety of their products. Therefore, the FDA has always recommended the use of any test is necessary to ensure the safety of their products and the ingredients used. Therefore, the companies can justify the safety and effi cacy of their prod- uct in various ways (29). The use of natural edible ingredients could be of initial guarantee of the safe fi nal product. After that, performing an in vivo test using human volunteers is considered most important to guarantee the safety of the used product. Accordingly, most of the used ingredients in Figure 3. Photomicrograph of the emulgel.

JOURNAL OF COSMETIC SCIENCE 10 this formulation were edible and of natural origin, and all of them were approved by the FDA for their use in food, cosmetic, and drug formulation as reported in the subsequent in vivo results (30). Demographic analysis . An in vivo assessment was conducted on human volunteers to assess the general sensorial properties and safety of the obtained natural emulgel. For this pur- pose, a total of 20 volunteers were enrolled in the study. Demographic and physiological skin characteristics are shown in Table VII. More than half of them were females (72%) with an average age of 18–30 years. The majority of the volunteers had normal skin (52%), and about 60% of the volunteers had fair skin color. General organoleptic and sensorial properties analysis . Based on the organoleptic and sensorial analyses presented in Table VI and Figure 4, there were signifi cant differences between the LG emulgel and blank emulgel in terms of cooling effect, astringent, and odor. More- over, there was a signifi cant difference in the overall evaluation between the two emulgels, where the p-value was less than 0.05. The means of organoleptic characteristics of both emulgels were compared (Table VII). The LG-based emulgel could be suitable for skin moisturization and overall suitable cos- metic properties. ANALYSIS Q-PARAMETERS The Q-parameters are developed by the scientist Di Qu et al. and have recently been added in the calculation formula. They could only be obtained in mode 1 for equal suc- tion and relaxation time. To obtain these parameters, two horizontal lines have to be Table VI Demographics and Physiological Skin Characteristics of the Study Population Baseline characteristic Frequency Percentage (%) Gender Male 14 28 Female 36 72 Socioeconomic status Low 0 0 Middle 35 70 High 15 30 Skin type Normal 26 52 Oily 7 14 Dry 17 34 Skin color Light 13 26 Fair 30 60 Dark 7 14 Skin sensitivity Yes 2 4 No 48 96