A carregar...
Publicação
Atividade fotoprotetora de extratos de punica granatum L.: avaliação in vitro
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 941.62 KB | Adobe PDF |
Autores
Resumo(s)
A radiação ultravioleta (UV) em excesso promove graves problemas de pele tais como eritema solar, fotoenvelhecimento e cancro de pele. Os filtros solares atuam na prevenção de doenças através de filtros químicos (origem sintética ou natural) e filtros físicos. De uma forma geral, os filtros físicos refletem as radiações UV e os filtros químicos absorvem a energia das radiações UV. Os filtros solares químicos de origem natural com atividade fotoprotetora são desenvolvidos para formulações dermocosméticas. Estas substâncias químicas devem ser atóxicas e compatíveis com o veículo do produto dermocosmético. Além disso, devem apresentar estabilidade físico-química ao longo de um determinado tempo. A romã (Punica granatum L.) é fruto de uma árvore cultivada em grande parte do planeta. No interior do fruto existem sementes carnudas. Estudos encontrados na literatura demonstram que a romã contem compostos químicos propícios para fotoproteção, tais como, antioxidantes, antocianinas e compostos fenólicos. Neste trabalho experimental foram preparados extratos de material vegetal fresco de romã com diferentes solventes: extrato puro, extrato aquoso, extrato hidroalcoólico, extrato glicólico e extrato oleoso. Estes extratos foram incorporados em gel de carbopol. Foi determinado o fator de proteção solar in vitro dos diferentes extratos de romã e extratos de romã incorporados em gel. A determinação do fator de proteção solar foi feita através do método de Mansur por ser uma metodologia simples e de baixo custo. A estabilidade acelerada dos geles com extratos de romã foi efetuada através de análises físico-químicas (pH e viscosidade) e características organolépticas. Perante os resultados obtidos verificou-se que as características organolépticas e físico-químicas não sofreram grandes alterações ao longo do estudo de estabilidade acelerada de 28 dias. O fator de proteção solar nos extratos e gel com extratos estudados apresentaram valores muitos baixos, abaixo do valor mínimo considerado para a atividade fotoprotetora. Estes resultados mostraram a necessidade de otimização da metodologia de extração de compostos químicos presentes na romã para melhorar o nível do fator de proteção solar.
Ultraviolet (UV) radiation in excess leads to skin problems such as sunburn erythema, photoaging and cancer. The purpose of the sunscreens is to prevent diseases through chemical filters (synthetic or natural) and physical filters. Generally, physical filters reflect UV radiation and chemical filters acts on the absorption of energy from UV radiation. Chemical sunscreens of natural origin with photoprotective activity are developed for dermocosmetic formulations. These substances must be non-toxic and compatible with the vehicle of the dermocosmetic product. In addition, they must show physicochemical stability over a certain period of time. The pomegranate (Punica granatum L.) is the fruit of a tree cultivated in a large part of the planet. Inside the fruit are succulent seeds. Studies found in the literature demonstrate that pomegranate contains chemical compounds likely to result in successful photoprotection, such as antioxidants, anthocyanins and phenolic compounds. In this experimental work, extracts of fresh plant material from pomegranate were prepared with different solvents: pure extract, aqueous extract, hydroalcoholic extract, glycolic extract and oil extract. These extracts were incorporated into carbopol gel. The in vitro sun protection factor of different pomegranate extracts and pomegranate extracts incorporated in gel was determined. The determination of the sun protection factor was based on the method of Mansur because it is a simple methodology and of low cost. The accelerated stability of gels with pomegranate extracts was performed through physical-chemical analyses (pH and viscosity) and organoleptic characteristics. Based on the results obtained, it was verified that the organoleptic and physical-chemical characteristics did not change after 28 days of accelerated stability. The sun protection factor in the studied extracts and gel with extracts had very low values, below to the minimum value considered for photoprotection. These results led to the need to optimize the methodology for extracting chemical compounds present in pomegranate in order to improve the level of sun protection factor.
Ultraviolet (UV) radiation in excess leads to skin problems such as sunburn erythema, photoaging and cancer. The purpose of the sunscreens is to prevent diseases through chemical filters (synthetic or natural) and physical filters. Generally, physical filters reflect UV radiation and chemical filters acts on the absorption of energy from UV radiation. Chemical sunscreens of natural origin with photoprotective activity are developed for dermocosmetic formulations. These substances must be non-toxic and compatible with the vehicle of the dermocosmetic product. In addition, they must show physicochemical stability over a certain period of time. The pomegranate (Punica granatum L.) is the fruit of a tree cultivated in a large part of the planet. Inside the fruit are succulent seeds. Studies found in the literature demonstrate that pomegranate contains chemical compounds likely to result in successful photoprotection, such as antioxidants, anthocyanins and phenolic compounds. In this experimental work, extracts of fresh plant material from pomegranate were prepared with different solvents: pure extract, aqueous extract, hydroalcoholic extract, glycolic extract and oil extract. These extracts were incorporated into carbopol gel. The in vitro sun protection factor of different pomegranate extracts and pomegranate extracts incorporated in gel was determined. The determination of the sun protection factor was based on the method of Mansur because it is a simple methodology and of low cost. The accelerated stability of gels with pomegranate extracts was performed through physical-chemical analyses (pH and viscosity) and organoleptic characteristics. Based on the results obtained, it was verified that the organoleptic and physical-chemical characteristics did not change after 28 days of accelerated stability. The sun protection factor in the studied extracts and gel with extracts had very low values, below to the minimum value considered for photoprotection. These results led to the need to optimize the methodology for extracting chemical compounds present in pomegranate in order to improve the level of sun protection factor.
Descrição
Trabalho Final de Mestrado Integrado, Ciências Farmacêuticas, 2021, Universidade de Lisboa, Faculdade de Farmácia.
Palavras-chave
Punica granatum Fator de proteção solar Estabilidade acelerada Mestrado integrado - 2021