ABSTRACT
This work presents the physicochemical properties of the prepared lac lakes. The study revealed the stability, cytotoxicity and use of lac lake pigment as a cosmetic colorant. SEM, XRD and DSC were used to study the characteristics of the lac lakes.. The color stability of lac dye and its lakes was investigated at ambient temperature and at 45 °C, in sunlight,fluorescent light and darkness, for 3 months. Cytotoxicity on human dermal skin fibroblast cell lines was tested using MTT assay and the use of the lakes as a colorant in lip color product was studied. Different metal salts resulted in lac lakes of different shades and appearance. SEM, XRD and DSC results indicated that the morphology and structure of lac dye were changed after reacting with metal salts which support the coordination of metal ion with lac dye. The lac lakes were not cytotoxic to human dermal skin fibroblast cells (0.78-100 µg/mL). Lac lakes exhibited less alteration of color shade over acidic and basic conditions when compared with the lac dye itself. Additionally, the lake pigments displayed better color stability than lac dye and produced an orange-brown shade of lip color product. The results suggest that lac lake pigments have good potential for use as cosmetic colorant.
ABSTRACT
Objective:To determine hydrophilic-lipophilic balance (HLB) value,stability of formulate emulsion and properties of sacha inchi oil.Methods:The physiochemical characteristics of sacha inchi oil were first investigated.Free radical scavenging property was studied by DPPH assay.HLB value of sacha inchi oil was experimentally determined by preparing the emulsion using emulsifiers at different HLB value.Sacha inchi oil emulsion was prepared using the obtained HLB and its stability was conducted by centrifugation,temperature cycling,and accelerated stability test.The efficiency of the prepared emulsion was clinically investigated by 15 volunteers.The primary skin irritation was performed using closed patch test.Subjective sensory assessment was evaluated by using 5-point hedonic scale method.Results:Peroxide value of sacha inchi oil was 18.40 meq O2/kg oil and acid value was 1.86 KOH/g oil.The major fatty acids are omega-3 (44％),omega-6 (35％) and omega-9 (9％).The vitamin E content was 226 mg/100 g oil.Moreover,sacha inchi oil (167 ppm)and its emulsion showed 85％ and 89％ DPPH inhibition,respectively.The experimental HLB value of sacha inchi oil was 8.5.The sacha inchi oil emulsion exhibited good stability after stability test.The emulsion was classified as non-irritant after tested by primary skin irritation method.The skin hydration value significantly increased from 38.59 to 45.21 (P ＜ 0.05) after applying sacha inchi oil emulsion for 1 month and the overall product satisfaction of volunteers after use was with score of 4.2.Conclusions:This work provides information on HLB value and emulsion properties of sacha inchi oil which is useful for cosmetic and pharmaceutical application.
ABSTRACT
Overexposure to ultraviolet (UV) radiation can cause a number of skin disorders such as erythema, edema, hyperpigmentation, immunosuppression, photoaging, and skin cancer. Since the level of UV radiation is increasing as a result of depletion of the stratospheric ozone and climate change, the protection of human skin against the harmful effects of UV radiation is an urgent need. Topical application of sunscreens is a strategy to protect the deleterious effect of UV radiation on the skin. Sunscreens today contain one or several synthetic UV filter molecules which protect the UV radiation exposed on the epidermis. These molecules are broadly divided into physical and chemical agents. Physical sunscreens reflect and scatter UVB, UVA and visible radiation. Chemical sunscreens act by absorbing ultraviolet radiation and re-emitting chemical energy as heat or light. Several synthetic UV filter molecules are available in the market but they have limited use because these active molecules may create adverse effects on human skin. Some information on possible photon induced reaction such as photoirritation, photosensitization and contact dermatitis by sunscreen products containing synthetic organic sunscreen agents. To overcome these side effects, naturally occurring compounds have gained considerable attention as photoprotective agents. Flavonoids, a group of natural occurring compounds, act as catalysts in the light phase of photosynthesis and as stress protectants in plant cells by scavenging reactive oxygen species (ROS). Natural flavonoids have the potential photoprotection because of their UV absorbing, their ability to act as direct and indirect antioxidants as well as anti-inflammatory and immunomodulatory agents which provide exciting platforms for the development of photoprotection. This review summarizes the structure and potential photoprotection activity of several natural flavonoids.