Spent coffee ground is an inexpensive and readily available by-product of the food industry which contains a high concentration of antioxidants. The purpose of this study was to use spent coffee oil (an abundant natural product) and Ganoderma lucidum spore oil (a natural skin care substance) to make nanoemulsions for use in cosmetic products for whitening skin and also as anti- aging. To this end, nanoemulsions of Ganoderma spore oil and spent coffee oil and nanoemulsions containing both oils (mix nanoemulsions) were made by spontaneous emulsification method. To investigate the effect of the manufactured nanoemulsions, the shaved back skin of mice was exposed to UVA radiation to create pigment followed by topical application of the formulations. The analysis of skin factors was checked by the skin analyzer device. From the results, the nanoemulsion (NE) of the oils as well as the NE containing both oils (Mix NE) showed improved performance compared to their bulk forms. The cell viability tests did not show cytotoxicity in the examined concentrations. The penetration studies on the skin using the Franz diffusion cell method indicated enhanced penetration of NE into the skin. The melanocyte cell culture demonstrated a reduction in melanin production, following treatment with the NEs. The animal studies exhibited a significant reduction in acne score of spent coffee oil NE and Mix NE when compared with the control group. Furthermore, the spots detected on the skin reduced significantly using Mix NE compared with hydroquinone cream and the control group. In conclusion, the developed nanoemulsion containing spent coffee oil and Ganoderma lucidum spore oil showed great potential as a skin whitening and anti-aging product in vivo.

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