Renê O. Couto

Isolation and quantitative HPLC-PDA analysis of lupeol in phytopharmaceutical intermediate products from Vernonanthura ferruginea (Less.) H. Rob.

Prior to obtain a standardized dried extract from V. ferruginea, lupeol was first time isolated from leaves and used as chemical maker. An analytical method using HPLC-PDA for lupeol determination in V. ferruginea intermediate products was developed using a C8 reverse-phase column, acetonitrile-acetic acid (99.99:0.01, v/v) as mobile phase at 0.8 mL min-1, oven temperature at 23-25 oC, sample injection volume at 30 µL and detection at 210 nm. The method presented linearity from 10 to 160 µg mL-1, accuracy, precision, robustness and suitable sensitivity proving to be a useful tool to the obtainment process of lupeol standardized dried extracts of V. ferruginea.

Preliminary studies of gastroprotective effect of Celtis iguanaea (Jacq.) Sargent leaves (Ulmaceae)

Antiulcerogenic activity of crude ethanolic extract of Celtis iguanaea leaves (CEE) was observed with experimental models such as ethanol, indomethacin, stress and pyloric ligation-induced gastric ulcers. Results obtained from indomethacin-induced ulcer showed the hexane fraction (HF) as the active fraction of CEE. This fraction inhibits the gastric acid secretion, increasing the gastric pH, decreasing the gastric acidity and total gastric contents. Neither the CEE nor the HF alters intestinal motility, thereby excluding a cholinergic antagonist mechanism. Further studies need to be conducted with HF in order to elucidate the active principle and the pharmacological mechanism involved.

In vitro safety and efficacy evaluations of a complex botanical mixture of Eugenia dysenterica DC. (Myrtaceae): Prospects for developing a new dermocosmetic product

In the context of developing a new natural product-based cosmetic, the in vitro efficacy and safety evaluations of a complex botanical mixture based on Eugenia dysenterica leaf hydroalcoholic extract (EDE) (2.5-1000μg/mL) were carried out. Chromatographic analysis demonstrated the presence of the tannin (ellagic acid) and flavonoids (quercetin and gallic acid) which characterize the EDE as a polyphenol-rich mixture. Using HFF-1 fibroblasts, it was shown that EDE promoted cell regeneration after UVA exposure. It also led to the inhibition of the collagenase, elastase and tyrosinase enzymes, which are involved in skin-related disorders. In terms of toxicological evaluation, the EDE was classified as non-phototoxic through the 3T3 Neutral Red Uptake Phototoxicity Test (OECD N° 432, 2004) and non-eye irritant by Bovine Corneal Opacity and Permeability (OECD N° 437, 2013) assay, in conjunction with corneal histomorphometric analysis. Furthermore, the EDE has no skin sensitization potential as demonstrated by a two-out-of-three prediction model [protein-binding/haptenization (OECD N° 442C, 2015), keratinocyte and dendritic cell activations]. In addition, it was shown that the EDE seems to be non-genotoxic through the cytokinesis-block micronucleus assay (OECD N° 487, 2014) using HepG2 cells. When considered together, these findings support the use of EDE botanical mixture in cosmetic/pharmaceutical products.

Voltametria de Pulso Diferencial (VPD) em estado sólido de manchas de Cromatografia de Camada Delgada (CCD): um novo método de análise para fitoativos antioxidantes

A new electroanalytical method coupling TLC-DPV in solid state was developed for quantitative determination of phytoantioxidants with medicinal purpose, e.g. rosmarinic acid (RA) in samples of phytopharmaceuticals, e.g. rosemary (Rosmarinus officinalis L.). The method showed to be feasible, presenting linearity in concentrations ranging from 0.694 x 10-3 to 9.526 x 10-3 mol L-1 (r = 0.9945), good sensibility, selectivity, reproducibility, repeatability, agility and affordable cost. The concentrations of RA in different extracts of rosemary ranged from 0.05 to 0.52 (% w/w), presenting high recovery levels when compared to HPLC.

The Monoglyceride Content Affects the Self-Assembly Behavior, Rheological Properties, Syringeability, and Mucoadhesion of In Situ–Gelling Liquid Crystalline Phase

This article reports the development of a precursor liquid crystalline system based on a mixture of monoglycerides (MO) and Cremophor(®) (CREM) that exhibits in situ gelation to a liquid crystalline phase. The effects of different MO/CREM ratios and the water content (WC) on several performance characteristics were investigated with a full factorial design. The formulations were characterized by polarized light microscopy, small-angle X-ray scattering, and water uptake assays. Rheological, syringeability, and mucoadhesion evaluation were also performed. The polarized light microscopy and small-angle X-ray scattering results for average and high MO/CREM ratios (2.1 and 4.0, respectively) indicated the coexistence of phases in transition to the liquid crystalline phase, independently of the WC. These systems became more viscous after taking up water, showing peaks characteristic of a cubic phase. Systems that had average and high MO/CREM ratios also exhibited shear-thinning behavior and high elasticity. Most systems showed suitable mucoadhesion for buccal purposes. Response surface methodology results demonstrated that the relative contribution of MO was the principal factor that affected the performance of the system. Accordingly, these precursor systems with average to high MO/CREM ratios and an average WC (10% w/w) demonstrated physicochemical and mucoadhesive properties that could enable them to be used as an in situ-gelling controlled drug delivery platform.

Combining amino amide salts in mucoadhesive films enhances needle-free buccal anesthesia in adults

ABSTRACT Needle‐phobia is usually a great concern in dentistry, and the replacement of painful injections by patient‐friendly needle‐free topical formulations would bring several advantages in dental practice worldwide. In this pursuit, the effects of combining prilocaine hydrochloride (PCL) and lidocaine hydrochloride (LCL) in different proportions in mucoadhesive films on their in vitro permeation and retention through porcine esophageal mucosa was studied. Complementarily, the permeation and retention of isolated LCL was investigated. The in vitro model used for evaluating buccal anesthetic penetration and retention in buccal epithelium was validated. In addition, the feasibility of a novel in vivo model to evaluate the painful sensation due to puncture “needle‐shaped” gum jaw of adults at shallow and deep levels was demonstrated. The in vivo clinical survey revealed the efficiency of the films, which had onset of anesthesia at 5 min, peak of anesthetic effect within 15 and 25 min and anesthesia duration of 50 min after being placed in maxillary sites. The in vitro drug flux, permeability coefficient and retention in the epithelium significantly correlated with in vivo onset, peak and extent of shallow and deep anesthetic effect. At shallow level, the permeation of LCL has shown to be closely related to the onset of anesthesia, while the penetration of PCL has a significant impact in the peak of anesthetic effect. Concerning the deep level, the penetration of PCL is required to attain the onset of anesthetic effect. The total amount of drug retained in the epithelium showed to modulate the extent of both shallow and deep anesthesia. Thus, the combination of LCL and PCL in mucoadhesive films may offer dentists and their patients a safe improvement for pain management during dental procedures. Graphical abstract Mucoadhesive films containing prilocaine (PCL) and lidocaine (LCL) hydrochlorides were effective for decreasing the painful sensation due to puncture “needle‐shaped” gum jaw of adults at shallow and deep levels. Figure. No caption available.