SENSORIAL AND STABILITY OF COSMETIC FORMULATIONS CONTAINING POLYSACCHARIDES OF PLANT OR BIOTECHNOLOGICAL ORIGIN

TF24

Sabrina Maira Bertucci, Lorena Rigo Gaspar, Patrícia M. B. G. Maia Campos

Departamento de Ciências Farmacêuticas

Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP

Universidade de São Paulo - USP

A new tendency in cosmetic formulations is the use of biotechnological raw materials like polysaccharides, and among them the ones produced by Klebsiella pneumoniae as well as their derivatives can be pointed out due to their proposed effects on cell renew, skin moisture and micro-relief. In addition, Myrtus communis leaves are rich in flavonoids, and its hydrolyzed extract contains different polysaccharides, which can also act in skin barrier function. On the other hand, in the development of cosmetic products, rheological studies have been largely used due to the possibility to obtain a correct profile of physical stability and to predict an instability process of cosmetic formulations under “accelerated” conditions. The objective of this study was to evaluate the physical stability and to perform sensorial analysis of cosmetic formulations containing polysaccharides produced by Klebsiella pneumoniae and/or polysaccharides from Myrtus communis hydrolyzed extract. The following formulations were developed:   F1: hydroxyethylcellulose (HEC), methylphenyl polysiloxane (MPPS), batyl alcohol and lecithin; F2: HEC, MPPS and behenyl alcohol, sodium stearoyl lactylate; F3: HEC, MPPS and C12-20 acid PEG-8 ester; F4: HEC and MPPS; F5: acrylate polymer and MPPS. These formulations were supplemented or not (vehicle) with 10% of polysaccharides produced by Klebsiella pneumoniae and/or 3% of polysaccharides from Myrtus communis hydrolyzed extract. These formulations were submitted to preliminary stability studies (centrifugation, pH and visual analysis) when stored at room temperature and at 37 and 45ºC for a week. In the study of the physical stability by the determination of rheological behavior, the formulations were stored at room temperature, 37 and 45ºC, for 28 days. Viscosity, consistency and flow index and thixotropy of the formulations were determined using a Brookfield cone and plate rheometer. The 2 most stable formulations were applied on the volunteers forearm skin, who answered a questionnaire about their perception concerning the cosmetic properties, as well sense of touch, spreadability, skin feeling just after the application (sensorial analysis). Formulations F1, F4 and F5 were considered more stable in preliminary stability tests and were submitted to the determination of rheological behavior. F4 presented more pronounced alterations in all analyzed rheological parameters than F1 and F5, thus, formulations F1 and F5 were considered more stable and were selected for the subjective analysis. F5 presented the higher degree of acceptance, showing the best sensorial. In addition, the presence of polysaccharides produced by Klebsiella pneumoniae in both formulations under study reduced their degree of acceptance.             In the experimental conditions of this study, it can be concluded that F1 (containing HEC, MPPS, batyl alcohol and lecithin) and F5 (containing acrylate polymer and MPPS) were considered stable, however F5 presented the higher degree of acceptance in subjective analysis, showing the best sensorial properties.