Unsaponifiable matter from oil of green coffee beans: cosmetic properties and safety evaluation.

CONTEXT: Unsaponifiable matter (UM), a fraction of green coffee oil (GCO) contains functional compounds responsible for desirable cosmetic properties such as UV-B absorption. OBJECTIVES: To evaluate oil content and sun protection factor (SPF) variability of the two most important species of coffee and, the toxic and cytotoxic effects, as well as cosmetic properties, including antioxidant and antimicrobial activities of UM obtained from green Coffea arabica seed oil. MATERIALS AND METHODS: The safety and potential cosmetic properties of UM extracted from green coffee oil (GCO) were evaluated by the brine shrimp viability and the MTT cytotoxicity assays. The SPF and antioxidant activity were evaluated using in vitro methods. RESULTS: Relevant cytotoxicity was found against keratinocytes for concentrations ≥25 µg/mL and in the brine shrimp assay (LC50 24 µg/mL). Antimicrobial and antioxidant activities (IC50 1448 µg/mL) were low in UM but SPF was 10 times higher than in GCO. CONCLUSION: UM is a novel potential UV-B absorbent but its use as a cosmetic ingredient should be better considered due to the considerable cytotoxicity shown in the experimental conditions described.

Oral supplementation with fish oil reduces dryness and pruritus in the acetone-induced dry skin rat model.

BACKGROUND: Pruritus and discomfort are often present in patients with xerosis and atopic dermatitis. Several studies suggest an important role of diet in skin pathophysiology. OBJECTIVE: This study evaluated the effect of dietary fatty acids in the skin physiology via an itch-related animal model with and without supplementation with fish oil (FO), a source of polyunsaturated fatty acids (PUFA), especially omega 3 (n-3). METHODS: Male Wistar rats were divided into two groups-non-supplemented (control) and supplemented with FO (3g/kg/day) by gavage for 90 days. Every 30 days, scratching and skin parameters (transepidermal water loss (TEWL), hydration, and local blood flow) were evaluated before and after dorsal skin exposure to acetone to induce the itch-related dry skin. At the end of the study, animals were sacrificed, and skin samples collected for fatty acids composition analysis by GC-FID. RESULTS: FO supplementation reduced the TEWL and increased the skin hydration, with significant changes from day 60 on, while skin microcirculation registered no changes. It also alleviated the acetone induced skin barrier alteration, revealed by a faster resolution of TEWL and hydration, and elimination of itch-related scratching induced by dry skin. These changes were associated with the shift in the skin fatty acids incorporation pattern (richer in n-3 with n-6/n-3<5) resulting from the FO supplementation. CONCLUSION: Skin barrier dynamics seem to be influenced by FO n-3 PUFA, with suppressive effects on the scratching behaviour induced by dry skin. Hence, long-term supplementation with n-3 PUFA rich nutrients might reinforce and restore cutaneous integrity and function.