Abstract Historically, phenol/croton oil deep chemical peeling has been very effective and has generated excellent results compared to other formulas used in dermatological clinics. However, it can cause serious side effects in patients sensitive to phenol. Therefore, this study aimed to develop a liquid crystalline structure containing croton oil (without phenol) as well as to evaluate the physical characteristics and cytotoxicity of this new system. Rational proportions of the croton oil, purified water, and polyethylene glycol hexadecyl ether were designed through a partial phase diagram to obtain 26 formulations. After macroscopic analysis and polarized light microscopy evaluation, formulations with lamellar liquid crystalline phase (4 samples) were identified and chosen to determine pH, size, polydispersion index (PDI), zeta potential, and rheological behavior. After 48 hours, three samples presented phase separation. Formulation 8 remained stable, but hydroxyethyl cellulose (HEC, 0.5%, w/w) was added to the aqueous phase, to prevent coalescence. Sample 8A exhibited a pH compatible with the skin, nanometric size, narrow PDI, negative zeta potential, and stability throughout the study period. The addition of HEC improved the organization of the system, making the formulation more stable. The oil, fractions of the oil, and the sample exhibited increasing cytotoxicity, respectively. This result could be attributed to the fractionation process of the vegetal matrix, and the surfactant present in the formulation increased the cell membrane permeability. The proposed approach successfully achieved a physically stable liquid crystal system containing croton oil.

Abstract Lemongrass (Cymbopogon citratus) is an aromatic plant of great significance in industries due to its essential oil characteristic aroma. Essential oils are concentrated plant extracts that evaporate when in contact with air and have low chemical stability, which can improve encapsulation techniques. This study aimed to evaluate the seasonal influence in the concentration of the predominant component citral of the essential oil of C. citratus and develop microparticles by spray drying containing this vegetal matrix. The lemongrass leaves were collected in the four seasons, and the essential oil was extracted by hydrodistillation. The chemical composition was determined by gas chromatography coupled with the mass spectrometry technique (GC-MS). Different proportions of arabic and guar gums were evaluated as encapsulating agents. Physicochemical analyses characterized the microparticle powder. GC-MS showed higher citral in the spring and summer (84.89% and 79.39%, respectively), and it was possible to identify a high amount of citral in the microparticles. Field-emission scanning electron microscopy showed agglomerate and collapsed microparticles. Fourier transform infrared spectroscopy suggested the essential oil encapsulation due to a band at 1675 cm-1 used as a reference, related to the acyclic monoterpenes of citral. X-ray diffraction showed the amorphous structure of the microparticles. Thermogravimetric curves of microparticles showed higher Tonset in microparticles than those observed for pure lemongrass essential oil, inferring that microencapsulation improved the thermal stability. This result confirms the lemongrass essential oil microencapsulation and its potential application in food products, drugs, or cosmetics.

Abstract Eugenol is a phenolic compound with numerous biological activities. It is widely used in dentistry to treat toothache and pulpitis. In particular, eugenol may be used for tooth whitening procedures to minimize dental sensitivity in patients. However, eugenol has some disadvantages such as its volatility, its photosensitivity, and immediate effect, which can be avoided by using pharmaceutical nanotechnology. The aim of the present study was to obtain, characterize, quantify, and evaluate the physicochemical stability of eugenol-loaded Eudragit RS100 nanocapsules. The nanocapsules (NCs) were prepared by interfacial deposition of the preformed polymer method. The NCs were characterized through morphological and spectroscopic studies. The encapsulation efficiency was achieved by quantifying the non-encapsulated eugenol using a previously developed and validated analytical method. The physicochemical stability of NCs was assessed at predetermined time intervals for 90 days after preparation. The nanocapsules were successfully prepared by the chosen method and had a predominantly spherical shape with a smooth surface. The mean size, the polydispersion index, and the zeta potential were in agreement to literature data. Infrared spectra ensured that the nanoencapsulation process did not result in chemical reactions between the drug and the polymer. The formulations showed encapsulation efficiency higher than 90% and remained stable after 60 days of preparation. Thus, eugenol-loaded Eudragit RS100 nanocapsules may be further considered as an alternative formulation for dental sensitivity in order to provide a controlled release, a decreased toxicity, and a better dental sensitivity relief.

Abstract The effect of the variety (Gala, Lis Gala and Fuji Suprema) and the ripening stage (unripe, ripe and senescent) of apples on the phenolic compounds (HPLC) and antioxidant capacity (FRAP and DPPH) of apple juices and ciders were evaluated. The phenolic content of the Gala and Lis Gala apple juices decreased from the unripe to ripe stages and increased from the ripe to the senescent stages, while in the case of Fuji Suprema these values decreased with senescence. Fermentation caused a reduction (17 to 50%) of phenolics and the most affected were hydroxycinnamic acids and flavanols. Principal component analysis confirmed the influence of variety, and the use of multivariate regression (PLS) made it possible to create significant models (p < 0.05) to predict the antioxidant activity. The phenolic composition of the juices at different ripening stages was related to the variety of apple, which influenced the effect of fermentation on these compounds.

The sugars in apple juice prove its authenticity and its sensory and nutritional properties. The aim of this study was to develop and validate a simple analytical method using high performance liquid chromatography with refractive index detection (HPLC-RI) to determinate and quantify the sugars sucrose, D-glucose, D-fructose, and D-sorbitol polyol in apple juices, as well as to analyze the juices from the Fuji suprema and Lis Gala cultivars at three ripening stages. The analytical performance parameters evaluated indicated that the method was specific for the compounds analyzed, and the linearity of the calibration curves of sugars showed high correlation coefficients (close to 1.0). The limits of detection and quantification are consistent with recommendations available in the literature for this type of matrix. Sample preparation is simple and generates small amount of residues. Over 70% of the sugars were determined in the juices of apples at the pre-ripe stage, with an increase during senescence. This method is applicable for the determination of sugars in juices and evaluation of apple ripening.

The hydroalcoholic extracts prepared from standard leaves of Maytenus ilicifolia and commercial samples of espinheira-santa were evaluated qualitatively (fingerprinting) and quantitatively. In this paper, fingerprinting chromatogram coupled with Principal Component Analysis (PCA) is described for the metabolomic analysis of standard and commercial espinheira-santa samples. The epicatechin standard was used as an external standard for the development and validation of a quantitative method for the analysis in herbal medicines using a photo diode array detector. This method has been applied for quantification of epicatechin in commercialized herbal medicines sold as espinheira-santa in Brazil and in the standard sample of M. ilicifolia.

The effect of hydroalcoholic extracts (HE) obtained from leaves of Cissus sicyoides (CS) on glucose tolerance (GT) was investigated in rats treated with dexametasone (DEX). Our results showed that HE intensified the decreased GT promoted by (DEX). Additionally, the flavonoids kaempferol 3-O-rhamnoside and quercetin 3-O-rhamnoside, obtained from aerial parts of CS, were used to study the incorporation of glucose to glycogen in soleo muscle. The results showed that both flavonoids did not show effect on glycogen synthesis. Thus, our data, in contrast to popular believe, did not reveal antidiabetic activity to SC.