Betulinic Acid Nanogels: Rheological, Microstructural Characterization and Evaluation of their Anti-inflammatory Activity.

BACKGROUND: Betulinic Acid (BA) is a lipophilic compound with proven beneficial results in topical inflammation. Nanogels (NG) are carriers of bioactive compounds with properties that make them good candidates to treat skin diseases. OBJECTIVE: The objective of this study was to evaluate the anti-inflammatory activity of BA carried in NG. METHODS: NG were composed of a nanoemulsion and a crosslinking agent (Carbopol 940®) applied at three concentrations (0.5, 1, and 1.5 %) and three activation times (6, 12 and 24 h). In order to select the optimal formulation, the NG were characterized mechanically and micro-structurally followed by evaluation of the BA anti-inflammatory activity in an in vivo model of auricular edema. We determined the edema inhibition activity as percent weight. Additionally, the anti-inflammatory activity of NG was validated through histological analysis. RESULTS: The formulation with the best viscoelastic properties was the one prepared with 0.5% carbopol and 6 h of activation. Microstructural examination of this formulation showed mostly spherical structures with a mean diameter of 65 nm. From the evaluation of edema and the histological analyses, we established that the NG of BA produced 52% inhibition. In contrast, a conventional gel and free BA produced 28% and 19% inhibition, respectively. CONCLUSION: The NG of BA were found to be good vehicles to treat skin inflammation.

Anti-inflammatory Activity of Curcumin in Gel Carriers on Mice with Atrial Edema.

Curcumin is a bioactive compound with proven antioxidant and anti-inflammatory activities, but has low water solubility and dermal absorption. The inflammatory process is considered as the biological response to damage induced by various stimuli. If this process fails to self-regulate, it becomes a potential risk of cancer. The objective of this work was to evaluate the anti-inflammatory activity of curcumin administered to mice with induced atrial edema using two topical vehicles: organogels and O/W-type nanogels at pH 7, Organogels and O/W-type nanogels at pH 7 were prepared, characterized and the anti-inflammatory activity was assessed. A histopathological analysis of mouse ears was performed and two gel formulations were selected. Thermograms of organogels indicated that increasing the gelling agent improved the stability of the system. Deformation sweeps confirmed a viscoelastic behavior characteristic of gels in both systems. During the anti-inflammatory activity evaluations, the nanogels demonstrated greater activity (61.8 %) than organogels; Diclofenac® (2-(2,6-dichloranilino) phenylacetic acid), used as a control medication achieved the highest inhibition (85.4%); however, the drug produced the death of 2 (40%) of the study subjects caused by secondary adverse events. Histopathological analysis confirmed the data.

Physicochemical properties of nixtamalized corn flours with and without germ.

This research studied the influence of the germ components on the physicochemical properties of cooked corn and nixtamalized corn flours as a function of the calcium hydroxide content (from 0 to 2.1 w/w) and steeping time (between 0 and 9h). A linear relationship was found between calcium content in germ and steeping time used during nixtamalization process. X-ray diffraction analysis showed that calcium carbonate is formed into the germ structure to 2.1 w/w of calcium hydroxide and 9h steeping time. The presence of the germ improves the development of peak viscosity in flours, and it is related to the increases in calcium concentration in germ and the formation of amylose-lipid complexes. No significant changes were observed in palmitic, stearic, oleic and linoleic acids of corn oil. The levels of further corn oil deterioration were 2.1 w/w of calcium hydroxide concentration and 9h of steeping time.

Physicochemical, morphological, and rheological characterization of Xanthosoma robustum Lego-like starch.

This work presents the physicochemical and pasting characterization of isolated mafafa starch and mafafa flour (Xanthosoma robustum). According to SEM images of mafafa starches in the tuber, these starches form Lego-like shaped structures with diameters between 8 and 35 µm conformed by several starch granules of wedge shape that range from 2 to 7 µm. The isolated mafafa starch is characterized by its low contents of protein, fat, and ash. The starch content in isolated starch was found to be 88.58% while the amylose content obtained was 35.43%. X-ray diffraction studies confirm that isolated starch is composed mainly by amylopectin. These results were confirmed by differential scanning calorimetry and thermo gravimetric analysis. This is the first report of the molecular parameters for mafafa starch: molar mass that ranged between 2×10(8) and 4×10(8) g/mol, size (Rg) value between 279 and 295 nm, and molecular density value between 9.2 and 9.7 g/(mol nm(3)). This study indicates that mafafa starch shows long chains of amylopectin this fact contributes to higher viscosity development and higher gel stability. The obtained gel phase is transparent in the UV-vis region. The viscosity, gel stability and optical properties suggest that there is potential for mafafa starch applications in the food industry.