Fabrication, physicochemical characterization and preliminary efficacy evaluation of a W/O/W multiple emulsion loaded with 5% green tea extract

Complex multiple emulsions have an excellent ability to fill large volumes of functional cosmetic agents. This study was aimed to encapsulate large volume of green tea in classical multiple emulsion and to compare its stability with a multiple emulsion without green tea extract. Multiple emulsions were developed using Cetyl dimethicone copolyol as lipophilic emulsifier and classic polysorbate-80 as hydrophilic emulsifier. Multiple emulsions were evaluated for various physicochemical aspects like conductivity, pH, microscopic analysis, rheology and these characteristics were followed for a period of 30 days in different storage conditions. In vitro and in vivo skin protection tests were also performed for both kinds of multiple emulsions i.e. with active (MeA) and without active (MeB). Both formulations showed comparable characteristics regarding various physicochemical characteristics in different storage conditions. Rheological analysis showed that formulations showed pseudo plastic behavior upon continuous shear stress. Results of in vitro and in vivo skin protection data have revealed that the active formulation has comparable skin protection effects to that of control formulation. It was presumed that stable multiple emulsions could be a promising choice for topical application of green tea but multiple emulsions presented in this study need improvement in the formula, concluded on the basis of pH, conductivity and apparent viscosity data.

Emulsões múltiplas complexas possuem excelente habilidade de agregar grandes quantidades de agentes cosméticos funcionais. Este estudo teve por objetivo encapsular grandes volumes de chá verde em uma emulsão múltipla clássica e comparar sua estabilidade com a emulsão múltipla sem o extrato do chá verde. Emulsões múltiplas são desenvolvidas usando cetil dimeticona copoliol como emulsificante lipofílico e o clássico polissorbato-80 como emulsificante hidrofílico. As emulsões múltiplas foram avaliadas por meio de vários aspectos fisico-químicos como condutividade, pH, análise microscópica e reologia. Estas características foram observadas por um período de 30 dias sob diferentes condições de armazenamento. Testes de proteção da pele in vivo e in vitro foram realizados para ambos os tipos de emulsões testadas, i.e. com o ativo em estudo (MeA) e sem ativo (MeB). Ambas as formulações apresentaram características comparáveis no que diz respeito aos diferentes fatores físico-químicos avaliados sob diferentes condições de armazenamento. A análise reológica mostrou que as formulações apresentaram comportamento pseudo-plástico sob contínuo estresse de cisalhamento. Os resultados dos testes in vivo e in vitro sobre a proteção da pele revelaram que a formulação ativa promoveu efeitos comparáveis à formulação controle. Nossos dados mostraram que emulsões múltiplas estáveis poderiam ser escolhas promissoras para a aplicação tópica do chá verde. Entretanto, a fórmula das emulsões múltiplas apresentadas neste estudo precisam ser melhoradas no que diz respeito ao pH, condutividade e viscosidade aparente.

Formulation and characterization of a cream containing terminalia chebula extract.

BACKGROUND: This study aimed to formulate a water-in-oil emulsion (formulation) of Terminalia chebula versus its vehicle (base) as control, and investigate its effects on skin melanin, skin erythema, skin moisture content, and transepidermal water loss (TEWL). MATERIAL AND METHODS: Base containing no active material, and formulation containing 5% concentrated extract of T. chebula, were developed. Different stability parameters were monitored at 8, 25, and 40 °C, as well as 40 °C + 75% relative humidity, for a period of 4 weeks. It was concluded that the creams remained stable at all storage conditions. Both base and formulation were applied to the cheeks of human volunteers for a period of 8 weeks. Different skin parameters were monitored every week to measure any effect produced by these creams. RESULTS: Changes in TEWL produced by base and formulation were insignificant (p > 0.05) with respect to time while significant (p ≤ 0.05) with respect to base and formulation. The skin moisture content increased after the application of formulation throughout the study period; this effect was insignificant (p > 0.05) with respect to time while significant (p ≤ 0.05) with respect to base and formulation. Both base and formulation showed insignificant (p > 0.05) effects on skin melanin content with respect to time. Skin erythema was reduced by the formulation. Both base and formulation produced statistically insignificant (p > 0.05) effects on skin sebum. CONCLUSION: Both creams were aesthetic with respect to sensory evaluation. T. chebula topical cream showed a positive rejuvenating effect on human skin. Hopefully, this study will encourage more attention towards the research and utilization of herbal medicines.

Pharmaceutical and biopharmaceutical evaluation of extracts from different plant parts of indigenous origin for their hypoglycemic responses in rabbits.

This study was designed to evaluate the hypoglycemic effects of different plant extracts in single and in combined formulation, in experimentally induced "diabetic rabbits". The extracts were obtained from seeds of Syzygium jambolana, fruits of Momordica charantia and leaves of Azadirachta indica. Treatment of diabetes with plant extracts was started at 8 days after alloxan injection. Rabbits were randomly divided into four groups, each group consisting of six rabbits. Each group of rabbits was given a dose of granules containing 200 mg/kg b.w. concentrated ethanolic extract of a plant while the fourth group was given a dose of granules consisting of combined extract of all three folk plants. Blood samples were drawn at 0, 2, 4, 8, 12, 24, 36, 48, 72 and 96 h. Serum glucose estimation was done by glucose oxidase kit method. Anti-diabetic effect was produced after 72 h in groups 1, 2 and 3 that were administered with a dose of granules of ethanolic extract of single plant but in group 4, treated with 200 mg/kg body weight of combined extract of all three plants, hypoglycemic effect was produced after 96 h. Hypoglycemic effects may be induced in rabbits by administration of extracts of various plant parts. The hypoglycemic effect produced by granules of single plant extract was more pronounced than antidiabetic effect produced by combining three extracts in a single formulation.

Outcomes of 3% green tea emulsion on skin sebum production in male volunteers.

This study was aimed to depict potential effects of stable formulation (water in oil emulsion), containing 3% green tea (Camellia sinensis L) extract on skin sebum production in healthy human volunteers. For this purpose formulation was designed using 3% ethanolic green tea extract and Abil®EM90 was used as an emulsifier. Formulation was applied to the cheeks of healthy human volunteers (n=10) for a period of 8 weeks. Measurements for skin sebum production were considered using Sebumeter MPA 5. Results were compiled and any effect produced by the formulation was justified statistically. It was observable that statistically significant (p < 0.5%) results were found for skin sebum production after long term application of the formulation. 3% formulation of green tea extract was ideal in all aspects and can be experienced in skin disorders like acne to further investigate its effects in unhealthy volunteers.