Measurements meet perceptions: rheology-texture-sensory relations when using green, bio-derived emollients in cosmetic emulsions.

OBJECTIVE: Product aesthetics and sensory performance can strongly influence a cosmetic product's acceptance by consumers. However, classic sensory analysis is time-consuming, expensive and does not provide information on the target group's preference. In the previous phase of this project, we had untrained consumers evaluate six cosmetic emulsions based on their aesthetics using a check-all-that-apply (CATA) survey. In this project, our goals were to quantitatively characterize the rheology and textural properties of the six cosmetic emulsions containing green, bio-derived emollients and identify statistical relationships between the consumers' description of products and the instrumental measurements. METHODS: Six emulsions were prepared-three with olive oil and three with heptyl undecylenate as an emollient. Four sensory-like attributes, namely firmness, work of shear, stickiness and adhesiveness, were tested using a texture analyser. Rheological characterization included continuous flow testing and oscillatory measurements. Droplet size and stability were also evaluated. Statistical relationships were quantified between measurements in this study and sensory survey results published previously. RESULTS: The textural and rheological results indicated that the emulsions were different-as designed. The texture and rheology measurements had analogous grouping outcomes to the consumers' discrimination. Emulsions 1 and 2 were the firmest, hardest to spread, stickiest and had the highest viscosity, while Emulsions 5 and 6 were the least firm, easiest to spread, less sticky than Emulsions 1 and 2, and had the lowest viscosity. Emulsions 3 and 4 fell in between the other two groups. Using olive oil instead of heptyl undecylenate as an emollient increased firmness, spreading, stickiness, viscosity and droplet size of the emulsions in every case-when comparing emulsions within each pair. All six emulsions had a shear-thinning behaviour. Viscosity and firmness directly correlated for the emulsions. Emulsions were visually stable at room temperature over the course of 6 months and viscosity remained relatively constant over this period also. CONCLUSION: Certain sensory attributes can be reliably predicted with instrumental measurements. Identifying and quantifying sensory-texture-rheology relationships can contribute to achieving appropriate product characteristics tailored to suit market needs.

Drug release from semisolid dosage forms: a comparison of two testing methods.

The aim of the present work was to extend our previous in-vitro drug release studies using semisolid dermatological bases with non-impregnated cellulose acetate membranes. A comparison of the performances of two apparatuses, the more commonly used Franz cell and the new modified USP (mini paddle with ointment holding cell) systems were applied to this work. Five different semisolid as well as two marketed preparations containing 1% diclofenac sodium were used. Complex, slightly non-linear release curves indicating sink conditions were found. This was explained by the co-diffusion of excipients modifying the characteristics of the membrane and the receiving medium dynamically. Although our test model is, as a rule, not suitable to establish an in-vivo-in-vitro correlation, good qualitative as well as quantitative correlations were found within some types of dermatological bases. The correlation between the results of the two in-vitro methods also depends on the type of semisolids studied. The release curve characteristics and the amount of diclofenac sodium released at 6 h were measured. Their repeatability and reproducibility were calculated. The slopes and Q-values were correlated with in-vivo data. In general, the modified USP method provided more precise results than the Franz cell method.

The potentiality of Trichoderma harzianum in alleviation the adverse effects of salinity in faba bean plants.

The interaction between sodium chloride and Trichoderma harzianum (T24) on growth parameters, ion contents, MDA content, proline, soluble proteins as well as SDS page protein profile were studied in Vicia faba Giza 429. A sharp reduction was found in fresh and dry mass of shoots and roots with increasing salinity. Trichoderma treatments promoted the growth criteria as compared with corresponding salinized plants. The water content and leaf area exhibited a marked decrease with increasing salinity. Trichoderma treatments induced a progressive increase in both parameters. Both proline and MDA contents were increased progressively as the salinity rose in the soil. Trichoderma treatments considerably retarded the accumulation of both parameters in shoots and roots. Both Na+ and K+ concentration increased in both organs by enhancing salinity levels. The treatment with Trichoderma harzianum enhanced the accumulation of both ions. Exposure of plants to different concentrations of salinity, or others treated with Trichoderma harzianum produced marked changes in their protein pattern. Three types of alterations were observed: the synthesis of certain proteins declined significantly, specific synthesis of certain other proteins were markedly observed and synthesis of a set specific protein was induced de novo in plant treated with Trichoderma harzianum.