Skin whitening activity of supercritical fluid extract from spent coffee in B16F10 melanoma cell

Recent patent applications for coffee and coffee by-products as active ingredients in cosmetics

OBJECTIVE

Coffee is one of the most consumed beverages worldwide, and its production and consumption generate large amounts of by-products annually. Coffee by-products and coffee beans are rich in bioactive compounds of great commercial value, including potential applications as active ingredients in skin care products and cosmetic formulations. In addition, there has been growing interest in the use of natural ingredients for cosmetic purposes. Considering the importance of coffee in the world economy, its chemical constituents with potential for cosmetic and dermatological application, and the importance of patents for innovation and technological development, the present study aimed to review recent patents involving coffee and coffee by-product use in cosmetics.

METHODS

This review was carried out using Espacenet. The following inclusion criteria were established: patents that included the terms "coffee" and "skin" in the title, abstract and claims and belonged to the classification A61Q, which is related to the "specific use of cosmetics or similar toilet preparations" considering the International Patent Classification (IPC) or Cooperative Patent Classification (CPC).

RESULTS

Considering the 52 patents analysed, the bean was the main way to obtain extracts (39), followed by green beans (7), silverskin (3), peel and pulp (1), pulp (1) and beans and leaves (1). The formulations are mainly intended for use in nonspecific areas of skin (29), eye areas (12), scalp hair (9) and lip skin (2) with claims of anti-ageing, moisturizers, sun protection, hair growth, anti-dandruff, etc. CONCLUSION: Coffee and its residues have high amounts of phenolic compounds, caffeine, fatty acids and other substances known to have important biological properties for the skin. Coffee and its by-products are promising ingredients to be incorporated into topical formulations, ensuring skin health benefits and reducing the environmental impact.

Supercritical Fluid Extract of Spent Coffee Grounds Attenuates Melanogenesis through Downregulation of the PKA, PI3K/Akt, and MAPK Signaling Pathways

The mode of action of spent coffee grounds supercritical fluid CO₂ extract (SFE) in melanogenesis has never been reported. In the study, the spent coffee grounds were extracted by the supercritical fluid CO₂ extraction method; the chemical constituents of the SFE were investigated by gas chromatography-mass spectrometry (GC-MS). The effects of the SFE and its major fatty acid components on melanogenesis were evaluated by mushroom tyrosinase activity assay and determination of intracellular tyrosinase activity and melanin content. The expression level of melanogenesis-related proteins was analyzed by western blotting assay. The results revealed that the SFE of spent coffee grounds (1–10 mg/mL) and its major fatty acids such as linoleic acid and oleic acid (6.25–50 μM) effectively suppressed melanogenesis in the B16F10 murine melanoma cells. Furthermore, the SFE decreased the expression of melanocortin 1 receptor (MC1R), microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2 (TRP-2). The SFE also decreased the protein expression levels of p-JNK, p-p38, p-ERK, and p-CREB. Our results revealed that the SFE of spent coffee grounds attenuated melanogenesis in B16F10 cells by downregulation of protein kinase A (PKA), phosphatidylinositol-3-kinase (PI3K/Akt), and mitogen-activated protein kinases (MAPK) signaling pathways, which may be due to linoleic acid and oleic acid.