No abstract

An oil obtained from the dried leaves of Lavandula stoechas L. in 0.77% yield was analyzed by capillaryGC and GC/MS. Fenchone (68.2%) and camphor (11.2%) were the main components of the 28 identified molecules. This oil has been tested for antimicrobial activity against six bacteria, and two fungi. The results showed that this oil was active against all of the tested strains; Staphylococcus aureus was the more sensitive strain.

Different extracts from myrtle berries were obtained using alcohol-water mixtures as an extraction medium in the range of 60-90% (v/v) to study the extraction efficiency in the preparation of myrtle liqueur. Flavonoids and anthocyanins were identified by high-performance liquid chromatography (HPLC) coupled with electrospray mass spectrometry and quantified during the maceration period by HPLC coupled with ultraviolet/visible detection. The antioxidant activity was tested by the 2,2-diphenyl-1-picrylhydrazyl assay. Dry matter, pH, and color parameters (L, a, b) were also analyzed. At the end of the maceration period, EE80 showed better anthocyanins stability and the highest total antioxidant activity (87.5%). These results suggest that the use of ethanol 80% provides the extract with the best characteristics for liqueur preparation. The present study contributes significantly to increase the marketing appeal of myrtle berries.

The adsorption of Hibiscus sabdariffa sp. anthocyanins onto a macroporous resin was studied in laboratory experiments. The anthocyanin aqueous extracts obtained from the calyces were used in agitated batch experiments with a macroporous resin. The adsorption kinetics and isotherms of H. sabdariffa anthocyanins on a selected macroporous resin was studied to determine the parameters that have to be optimized to recover the anthocyanins from aqueous extracts of the calyces. The adsorption kinetic experimental data were fit into a pseudo second order kinetic model, which was then used to determine several parameters such as the contact time necessary to reach equilibrium as well as the maximum adsorption capacity. The best fit for the equilibrium adsorption isotherm experimental data was obtained with the Langmuir isotherm model. Based on qualitative and quantitative interpretation of the experimental data, the resin that was tested here appeared to have good adsorption capacity for the anthocyanins even though the necessary time to reach equilibrium was particularly long.Three aspects of the desorption of anthocyanins from the resin were studied: the speed of release of the anthocyanins (desorption kinetics), the extent of the anthocyanin desorption depending on the adsorption contact time and finally, the influence of the mobile phase's characteristics.Practical ApplicationsThe purpose of this work is to facilitate the industrial production of a natural food colorant anthocyanin from H. sabdariffa calyces using a macroporous resin. To attain this, goal values from adsorption experimental data were computed and fit to theoretical adsorption models.The maximum adsorption capacity and the time necessary to reach equilibrium were determined. Qualitative and quantitative interpretation of the experimental data proved that the adsorbent/adsorbate system in study is a favorable process.The desorption of anthocyanins was also studied in order to determine the time necessary to achieve a satisfactory recovery rate, as well as the values of parameters that have a marked influence on the desorption efficiency.The obtained results and the calculated parameters will subsequently be used to plan colorant extraction at a bigger scale.

Previous methods of microencapsulation are unable to process particles smaller than 100 microm without organic solvents or the use of multistep processes. The present study investigates the feasiblity of a one-step spray-drying process to microencapsulate erythromycin and clarithromycin, antibiotics known to have an unpleasant, bitter taste. Mixtures of clarithromycin (5% by weight) or erythromycin (30% by weight) with a biodegradable polymer were prepared and spray-dried under specific conditions of temperature and turbine speed. This process resulted in the microencapsulation of 80% of each drug as determined by high pressure liquid chromatography. Particle size ranged from 1 to 80 microm as determined by electron microscopy. These data show that microencapsulation of macrolides using a spray-drying technique is feasible. Spray-drying microencapsulation might be useful in the formulation of palatable oral suspensions of bitter tasting drugs.