Curcumin, a phytochemical, exhibits several biological properties and has been studied for the treatment of psoriasis. To facilitate its transdermal permeation, permeation enhancers such as choline and geranic acid ionic liquid (CAGE-IL) have been studied. From this perspective, the research effort entertained herein aimed at developing and evaluating the stability of an emulsion prepared with curcumin (phytochemical from Curcuma longa L.) and locust bean gum (extracted from the seeds of the carob tree, Ceratonia siliqua), with CAGE-IL as a facilitator of transdermal permeation. Stability studies were carried out for six months, with analyses being performed at time intervals of 0 (24 h), 30, 60, 90, and 180 days. The samples were kept at 40 ± 2 °C, with 75 ± 5% relative humidity (RH). The parameters analyzed were morphological characteristics, pH (5.8-6.0), and spreadability. The samples were shown to be stable during the timeframe studied, maintaining adequate physicochemical characteristics and meeting quality specifications for cutaneous applications. CAGE-IL, in addition to facilitating permeation of the active substance, also favored the formation of a stable emulsion encompassing nanosized particles (134.3 ± 2.6 nm) in a simple fashion and with only a few components.

We addressed some physicochemical and biological differences in commercial turmeric, acquired from both handling pharmacies and stores selling natural products for quality assessment. For this, it was determined the melting point, antioxidant activity by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), antimicrobial activity via the agar disk-diffusion assay, metallic contaminants by X-ray fluorescence with energy dispersion (EDXRF), spectral behaviors by Fourier transform infrared (FTIR) and ultraviolet-visible (UV-Vis) and determination of curcumin concentration by UV-Vis. The results obtained of the several commercial turmeric samples were not homogeneous, showing in fact significant differences regarding melting points, UV-Vis spectral scan profiles, and FTIR spectra, presenting toxic metals and quite low curcumin contents. This sheds light on the urge to implement adequate quality control in this type of raw material for human safe use of curcumin. Particularly, contamination with heavy metals, such as mercury, is a serious health problem, due to its high toxicity and accumulative power in the body.