RESUMO
Skin ageing is characterized by features such as wrinkles, loss of elasticity, laxity, rough-textured appearance, melasma and freckles. Several researches have focused for preventing, and treating skin ageing by many natural ingredients. This study aimed to assess the anti-ageing activities for anti-skin ageing of the ethanolic extracts of Pink rambutan (PR) (Nephelium lappaceum Linn.) from leaves (L), branches (B), seeds (S), and peels from ripe (R) and young (Y) fruits. The extraction yields of all Pink Rambutan (PR) extracted by the Maceration (M) and the Soxhlet extraction (Sox) using 95% ethanol as a solvent, ranged from 10.62% to 30.63%. Flavonoids were found as the main phytochemicals in almost all the PR extracts. The PR-Y-M and PR-Y-Sox extracts gave the highest total phenolic contents by the Folin-Ciocalteu assay of 67.60 ± 4.38 mgGAE/g, and total flavonoid contents by the modified aluminum chloride colorimetric assay of 678.72 ± 23.59 mgQE/g, respectively. The PR-L-M extracts showed the highest three anti-oxidative activities; the free radical scavenging (SC50 of 0.320 ± 0.070 mg/mL), the lipid peroxidation inhibition (LC50 of 0.274 ± 0.029 mg/mL), and the metal chelation activity (MC50 of 0.203 ± 0.021 mg/mL). All the PR extracts at 0.01 and 0.1 mg/mL showed no cytotoxicity on B16F10 cells, and human skin fibroblasts, respectively. Likewise, the PR-R-Sox extract exhibited the highest anti-melanogenesis on B16F10 cells (52.7 ± 0.9%) and, the mushroom tyrosinase inhibition activity (IC50 of 0.04 ± 0.02 mg/mL), which was significantly comparable to kojic acid (p < 0.05). The PR-Y-Sox extract showed the collagen biosynthesis by the Sirius Red method, and the stimulation of anti-ageing genes (Sirt1 and Foxo1) on human skin fibroblasts by the RT-PCR method, which were similar to standards Ê-ascorbic acid and resveratrol, respectively. This study suggests that the PR-R-Sox and PR-Y-Sox extracts can be further developed as natural anti-ageing agents for whitening and anti-wrinkle in the cosmetics, cosmeceutical, and pharmaceutical industries.
RESUMO
CONTEXT: Bambara groundnut (BG), originally from Africa, is widely distributed in Asian countries, especially in southern Thailand, and is used for food and functional foods. There is no report on the use of BG for ethnomedicine or cosmetics. OBJECTIVE: To investigate collagen biosynthesis stimulation and anti-melanogenesis of the BG extracts. MATERIALS AND METHODS: The hulls (H) and seeds (S) of BG were collected from Trang province, Thailand and extracted by Soxhlet (S) and maceration (M) using ethanol, and boiled with distilled-water (B). Total phenolic (TPC) and total flavonoid (TFC) contents were quantified. The three antioxidant and tyrosinase inhibition activities were determined by DPPH, FIC and FTC; and the modified dopachrome methods, respectively. The collagen biosynthesis and the anti-melanogenesis activities were investigated by Sirius-Red and the melanin content assay. RESULTS: The yields of BG extracts ranged from 1.72% to 9.06%. The BG-SS extract gave the highest TPC and TFC. The BG-HM extract showed the highest antioxidant activities (SC50 of 0.87 ± 0.02 mg/mL, MC50 of 1.83 ± 0.09 mg/mL and LC50 of 0.70 ± 0.06 mg/mL), tyrosinase inhibition activity (IC50 of 0.45 ± 0.23 mg/mL), and anti-melanogenesis activities (72.9 ± 0.08%), whereas the BG-SB extract exhibited the highest stimulation of collagen biosynthesis (18.04 ± 0.03%). All BG extracts at 0.1 mg/mL showed no cytotoxicity on human dermal fibroblasts. DISCUSSION: The biological activities of BG extracts might be from their phytochemicals, especially phenolic and flavonoid contents. CONCLUSION: The BG-HB and BG-HM extracts might be promising novel active sources for anti-aging and whitening cosmeceuticals.
