Abstract:The aim of this research was to study the effect of local raw materials on the formulation of a base cream formulation and determine the optimum proportion of each material that gives the required properties. Physicochemical properties of cream formulations can be affected by their viscosity, spreadability, and particle size. The quality of the base cream is directly linked to the basic material used in the formulation. Screening of independent factors, namely oil phase (sesame oil, soybean oil, and liquid paraffin), aqueous phase (Aloe vera gel, propylene glycol, and glycerol), and surfactant (soy lecithin, tween, and soy lecithin/tween) was done to choose the best raw material required for the preparation of the base cream. Based on the screening criteria, sesame oil, Aloe vera gel, and soy lecithin were chosen as the best local raw materials. Using a multi-response optimization, the mixing fractions of sesame oil, Aloe vera gel, and soy lecithin were found to be 24%, 28%, and 10%, respectively. This base cream can be used as a suitable matrix for formulation in the cosmetic and pharmaceutical industries.

Piliostigma thonningii (Schum.) Milne-Redh. is a plant rich in quercetin-3-O-rhamnoside (quercitrin), a flavonoid involved in the antioxidant and antimicrobial processes. Microwave assisted extraction (MAE) is a method which gives better extraction yield, enhance the quality of extracts while decreasing the extraction time. This effect, a sequential optimization by response surface methodology using a central composite design, help to determine the optimal conditions for obtaining more antioxidant compounds of P. thonningii leaves. The response surface curves showed that there was a positive interaction between the extraction time and the solvent concentration on the DPPH scavenging and iron chelating activities of the extracts. The optimal ethanolic extraction parameters for the highest yield of flavonoids were an extraction time of 69 s, an irradiation power of 380 W and a solid-liquid ratio of 1/10 (w/v). On the residue, the optimal extraction parameters for simultaneously obtaining the highest flavonoids yield and the highest antioxidant activity were an extraction time of 49 s, an irradiation power of 520 W and an ethanol concentration of 67% (v/v). HPLC analysis has shown the second optimization helped to further maximize the extraction of active compound quercetin-3-Orhamnoside. Electron microscopy of the powders before and after extraction has shown that microwave heating causes cellular damage. Compared to the maceration extraction method, the combined extracts of sequential MAE provide higher antioxidant activities.

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Background Extraction of active compounds from plants using microwave can be utilized as an alternative solution for conventional extraction. To well understand this technology, the study of the modelization and kinetics mechanism of the extraction method is necessary. This study aimed to evaluate the suitable kinetics models for MAE of the Xanthones from Securidaca longepedunculata Fresen roots. Results The experimental data (xanthones versus time, power and ratio, respectively) were fitted to three-parameter empirical kinetics models. The second-order models appear to be the best fit to explain kinetics study of MAE than the first model. The second-order model was acceptable, with elevated value of the correlation coefficient (R2 = 0.9861), showing that it perfectly relates the process. Conclusion Based on the results obtained, the extraction of xanthones from roots of S. longepedunculata is done successively in two steps, washing and diffusion of compounds from matrices as described by second-order kinetics model. The latter could report the kinetics model of extraction process from S. longepedunculata Fresen using microwave technology.