Caffeic Acid in Dermatological Formulations: In Vitro Release Profile and Skin Absorption.

AIM AND OBJECTIVE: Caffeic acid (CA) is a cinnamic acid derivative, found in many vegetable products, with powerful antioxidant activity, the ability to increase collagen production and capacity to prevent premature aging of the skin. The classic emulsions of CA are widely used by the consumer to provide a pleasant, refreshing sensorial experience; however, preparations developed in the form of dry film are presented as a technological alternative due to its facile and safe transportation. The aim of this study was to evaluate the release, permeation, and retention of CA in a film and emulsion through in vitro experiments. MATERIAL AND METHODS: The release evaluation of CA from the emulsion and the film was performed using modified Franz diffusion cells, with an area of 1.77 cm², using Microette equipment (Hanson Research) with a cellulose membrane. The evaluation of the permeation of CA from the formulations was conducted using a similar technique of release, except that a biological membrane was used. RESULTS: High release of active compound and reduced permeation was observed, indicating that CA was able to be retained in the epidermis/dermis, where it should have the desired action. The concentration of caffeic acid in the skin was higher for the film formulation than for the emulsion. This demonstrates a greater efficiency of this type of innovative release system, besides its facile and safe transportation. CONCLUSION: The formulations tested in this paper can release caffeic acid with a Higuchi kinetic profile, in which release of active ingredient occurs by a diffusion process. The film formulations exhibited a lower permeation rate and higher retention in the skin, which is essential for a cosmetic product. The concentration of CA in the skin was also higher for the film formulation when compared to the emulsion. This demonstrates a greater efficiency of this type of innovative release system, in addition to its easy and safe transportation. Therefore, it is possible to suggest CA as a promising substance for dermal use due to its antioxidant, anti-inflammatory, antimicrobial, and collagen production stimulating activity.

Trypanocidal Activity of Flavokawin B, a Component of Polygonum ferrugineum Wedd.

The trypanocidal potential of the natural chalcone flavokawin B, which was isolated from the hexanic extract of Polygonum ferrugineum Wedd., is reported here. Although flavokawin B is widespread, this is the first report about its trypanocidal properties on both Trypanosoma cruzi (IC50 = 9.5 µM, IC50 = 34.7 µM benznidazol, Y strain) epimastigotes and Trypanosoma brucei (IC50 = 4.8 µM, IC50 = 6.4 µM pentamidine, 29-13 strain) procyclic forms, which was also corroborated on T. brucei strain 427 (IC50 = 6.2 µM). In order to learn more about its properties, unspecific cytotoxicity on Hep G2 cells was investigated as well as the trans-splicing inhibitory potential on T. brucei cells. The results shown here point to flavokawin B as a candidate in the search for new agents. It is also cheaper and less toxic than the available drugs to treat trypanosomiasis with a special focus on sleeping sickness disease.

Ethyl ferulate, a component with anti-inflammatory properties for emulsion-based creams.

Ethyl ferulate (FAEE) has been widely studied due to its beneficial heath properties and, when incorporated in creams, shows a high sun protection capacity. Here we aimed to compare FAEE and its precursor, ferulic acid (FA), as free radical scavengers, inhibitors of oxidants produced by leukocytes and the alterations in rheological properties when incorporated in emulsion based creams. The cell-free antiradical capacity of FAEE was decreased compared to FA. However, FAEE was more effective regarding the scavenging of reactive oxygen species produced by activated leukocytes. Stress and frequency sweep tests showed that the formulations are more elastic than viscous. The viscoelastic features of the formulations were confirmed in the creep and recovery assay and showed that the FAEE formulation was less susceptive to deformation. Liberation experiments showed that the rate of FAEE release from the emulsion was slower compared to FA. In conclusion, FAEE is more effective than FA as a potential inhibitor of oxidative damage produced by oxidants generated by leukocytes. The rheological alterations caused by the addition of FAEE are indicative of lower spreadability, which could be useful for formulations used in restricted areas of the skin.

Estudo fitoquímico de goiaba (Psidium guajava L. ) com potencial antioxidante para o desenvolvimento de formulação fitocosmética / Phytochemical study of guava (Psidium guajava L. ) with potential antioxidant activity aiming at developing a phytocosmetic formulation

Considerando-se a qualidade dos fitoterápicos, é importante salientar que a preocupação com esta questão inclui rigoroso acompanhamento das diferentes etapas do desenvolvimento e produção destes produtos, desde a coleta do vegetal até a disponibilidade do produto final. Neste trabalho, foram realizados o controle da qualidade, o potencial antioxidante como também ensaios biológicos in vitro do fruto da goiabeira (Psidium guajava L.), para o desenvolvimento de uma formulação fitocosmética. Os resultados obtidos mostraram que o fruto apresenta taninos e flavonóides, bem como atividades antioxidante e antimicrobiana. A análise microbiológica não apresentou crescimento de patógenos na formulação desenvolvida entre os outros testes realizados. Destaca-se a importância do estabelecimento do controle da qualidade para as plantas, a fim de que sejam utilizadas para o desenvolvimento de uma formulação fitocosmética segura, eficaz e com qualidade.

Considering the quality of the phytotherapic products, it is important to point out that the concern with this question includes rigorous accompaniment of the different stages of the development and production of these products, since the collection of the vegetable until the availability of the end product. In this work the quality control, the antioxidant potential were performed as also biological assays in vitro of guava fruit (P. guajava L.), for the development of a phytocosmetic formulation. The results had shown that the fruit presents tannins and flavonoids, as well as antioxidant and antimicrobial activities. The microbiological analysis did not present growth of pathogens. The importance of the establishment of the quality control for the plants is relevant, so that they are used for the development of a phytocosmetic formulation considered safe, efficient and with quality.

Avaliação da atividade anti-séptica de extrato seco de Stryphnodendron adstringens (Mart. ) Coville e de preparação cosmética contendo este extrato / Antiseptic activity evaluation of the dry extract from Stryphnodendron adstringens (Mart. ) Coville and cosmetic preparation

As espécies pertencentes ao gênero Stryphnodendron são conhecidas como "barbatimão" e são nativas do cerrado brasileiro. Possuem taninos como metabólitos secundários primordiais de suas cascas apresentando, entre outras, atividade antimicrobiana e cicatrizante. A concentração bactericida mínima (CBM) do extrato seco das cascas de Stryphnodendron adstringens frente a duas bactérias Gram-positivas e uma bactéria Gram-negativa foi determinada pela técnica de diluição em tubos. A atividade antimicrobiana do extrato seco e a atividade anti-séptica de sabonete líquido contendo o extrato seco foram avaliadas pelo método de difusão em ágar. O extrato apresentou valores de concentração bactericida mínima de 50 mg/mL frente a Staphylococcus aureus e 75 mg/mL contra Staphylococcus epidermidis e Escherichia coli e no teste de difusão em ágar, S. aureus apresentou maior sensibilidade ao extrato seco que as outras bactérias. O sabonete líquido mostrou maior eficiência na atividade anti-séptica contra as bactérias testadas na concentração de 100 mg de extrato/mL de sabonete.

The species of the genus Stryphnodendron are known as "barbatimão" and are native from Brazilian "cerrado". They present tannins as main secondary metabolites of their barks and show antimicrobial and cicatrisation activity among others. The minimum bactericidal concentration (MBC) of the dry extract from the barks of Stryphnodendron adstringens against two Gram-positive and one Gram-negative bacteria was done using methodology of broth dilution in tubes. The antimicrobial activity of the dry extract and the antiseptic activity of the liquid soap containing that dry extract were evaluated by agar difusion method. For the extract were obtained the minimum bactericidal concentration values of 50 mg/mL against Staphylococcus aureus and 75 mg/mL against Staphylococcus epidermidis and Escherichia coli and by agar difusion, S. aureus showed more sensibility to the dry extract than the other bacteria. The liquid soap showed efficiency in the antiseptic activity against the bacteria studied at the concentration of 100 mg of extract/mL of soap.

Evaluation of efficacy of preservatives associated with Achillea millefolium L. extract against Bacillus subtilis

A eficácia antimicrobiana de conservantes empregados em formulações cosméticas foi avaliada usando Phenova® e Imidazolinidil uréia que inibiram o crescimento de Bacillus subtilis no extrato de Achillea millefolium L. e Nipagin®/ Nipasol® 0,2 por cento em propilenoglicol não apresentaram efeito microbicida.