A. A. S. Araújo

Inclusion complex of (−)-linalool and β-cyclodextrin

Abstract(−)-Linalool is a monoterpene alcohol which is present in the essential oils of several aromatic plants. Recent studies suggest that (−)-linalool has antimicrobial, anti-inflammatory, anticancer, antioxidant, and antinociceptive properties in different animal models. The aim of this study was to prepare and characterize inclusion complexes of (−)-linalool with β-cyclodextrin (β-CD). Equimolar binary (−)-linalool/β-CD systems were prepared by physical mixture, paste (PM), and slurry methods (SC) and characterized by differential scanning calorimetry, thermogravimetric analysis, FT-IR spectroscopy, X-ray diffractometry, Karl Fisher titration, and scanning electron microscopy. Thermal characterization indicates the occurrence of complexation, mainly in paste complexes, which is present in the interval from 140 to 280xa0°C a gradual mass loss (4.6xa0%), probably related to (−)-linalool loss. FT-IR spectra showed changes that may be related to the formation of intermolecular hydrogen bonds between (−)-linalool and β-CD. The new solid-phase formed using the PM and SC methods, had a crystal structure which was different from the original morphology of β-CD.

Enhanced analgesic activity by cyclodextrins – a systematic review and meta-analysis

Introduction: Analgesics can be ineffective in treating some types of pain, hence, improved drug delivery systems could optimize their efficacy. Area covered: The authors conducted a systematic review to evaluate the analgesic activity of compounds complexed in cyclodextrins, analyzing whether these complexes improved analgesic efficacy. The search terms ‘analgesics’, ‘cyclodextrins’ and ‘drug effects’ were used to retrieve articles in SCOPUS, PUBMED and EMBASE. A total of 22 papers were identified. In the clinical studies, there was greater efficacy in the complexed drug when compared with control groups, with differences ranging from 25 to 83%. Through a meta-analysis, the preclinical studies showed that the complexed drug had a significantly (p < 0.01) greater effect than the non-complexed drug. Expert opinion: The use of cyclodextrins can improve the efficacy of analgesic compounds, and they are an important tool in the search for greater analgesic effect. They may also be a way to reduce the therapeutic doses, and hence increasing the potential of the drug.

Natural compounds for solar photoprotection: a patent review

Introduction: Ultraviolet irradiation has deleterious effects on human skin, including tanning, sunburn, cancer and connective tissue degradation (photoaging). Botanical antioxidants have been shown to be associated with reduced incidence of photocarcinogenesis and photoaging through their photoprotective profile. Areas covered: Here, the authors summarized therapeutic patent applications concerning the employment of medicinal plants on the technological development of a formulation with photoprotective or photoaging application. So, the patent search was conducted in the databases WIPO, Espacenet, USPTO and Derwent, using the keywords – photoaging, photoprotection and the IPC A61K 8/97 (cosmetics or similar cleaning supplies obtained from vegetable origin, for example, plant extracts) and A61K 36/00 (medicinal preparations of undetermined constitution containing material from algae, lichens, fungi or plants, or derivatives thereof, for example, traditional herbal medicines). We found 180 patents, out of which 25 were evaluated using inclusion criteria as application of natural products with photoprotective or photoaging application. Expert opinion: We found that some patents related to the cosmetic compositions for improving skin wrinkle and either preventing or reducing the signs of photoaging and sunburn. The cosmetic compositions are manufactured in the form of a lotion, gel, soluble liquid, cream, essence, oil-in-water-type or water-in-oil-type formulation, containing the vegetal extracts as an active ingredient.

Thermal characterization of mangaba-based films

The purpose of this study was to evaluate the physical–chemical properties of starch (SF), mangaba (MF), and mangaba/starch-based films (MSF), using differential thermal analysis, thermogravimetry/derivative thermogravimetry, infrared spectroscopy, mechanical profile, and scanning electron microscopy. The films were prepared by casting process using sucrose and propyleneglycol as plasticizers. The thermal profiles of MF and MSF were similar and showed increased thermal stability. The mechanical properties of MF and MSF presented decreases of tensile strength and elastic modulus when compared with SF. The MSF showed the best thermal and mechanical characteristics.

Effect of Pulsed Therapeutic Ultrasound and Diosmin on Skeletal Muscle Oxidative Parameters

Cyclodextrins (CDs) have been widely used as a promising alternative in the formation of inclusion complexes with poorly soluble molecules. From this perspective, the present study aimed to study the inclusion complexes of diosmin in β-cyclodextrin, chemically quantify the diosmin-in-gel preparation and analyze the stability of the gels. Furthermore, we evaluated the effect of therapeutic pulsed ultrasound (TPU) in association with the gel-diosmin complex on the parameters of muscle damage and oxidative stress in rats. Serum creatine kinase (CK) levels were used as an indicator of skeletal muscle injury. Lipid peroxidation (thiobarbituric acid-reactive substances [TBARS]) and superoxide dismutase and catalase activities were used as indicators of oxidative stress. The results obtained indicated that the inclusion complex obtained by co-evaporation had the highest complexation efficiency and stability; there was no change in the features of diosmin on incorporation into the Carbopol gel. Additionally, a significant (pu2009<0.05) decrease was observed in CK levels (TPUu2009plus gel-diosmin: 178.4u2009±u200985.3u2009U/L) relative to the untreated group (527.8u2009±u200946.1u2009U/L). Levels of TBARS were lower in the TPUu2009plus gel-diosmin group (0.008u2009±u20090.0004u2009nmol malondialdehyde/mg protein, pu2009<0.05) compared with the untreated group (0.081u2009±u20090.011u2009nmol malondialdehyde/mg protein, pu2009<0.05, nu2009=u20096). Catalase activity did not statistically significantly differ between the treatment groups, and superoxide dismutase activity was lower in the diosmin-treated group (0.320u2009±u20090.11u2009U/mg protein) compared with the untreated group (0.983u2009±u20090.40u2009U/mg protein). These results suggest that TPU in association with the diosmin-gel complex is effective in reducing muscle damage and oxidative stress after mechanical trauma.

Characterization of Steel Production Dust and Their Use in Structural Ceramics

Electric arc furnace steel dust is a by-product of the steelmaking process and contains high amounts of iron and zinc and significant amounts of lead, chromium, and cadmium and others chemical compounds in minor proportion. However, the material recycling is very complex, mainly due to their mineralogical composition. In this study the characterization and application of this material is presented. Ceramics were produced with clay and variable amounts of steel dust. The bulk material was fired between 800 and 1000 °C. The influence to insertion of this material on the ceramic composition on the mechanical strength, linear shrinkage, water absorption, apparent density and bending strength of the ceramic samples was investigated. A blend of clay with 5% dust presents potential for use in structural ceramics production.

Use of bone physicochemical characterization and biochemical analyses in an experimental model

Osteoporosis is a systemic skeletal disease characterized by a disorder between bone reabsorption and formation with increase in bone fragility. The aim of this study was to evaluate the bone mass loss using solid-state techniques and biochemical assays to characterized bone samples of ovariectomized rats (OVX) and control group (CTR). The in vivo assays were carried out using biochemical analyses and bone mineral density (BMD) measurements. After the animals were euthanized, the femurs were examined using simultaneous differential thermal analysis (DTA), thermogravimetry/derivative thermogravimetry (TG/DTG) and atomic absorption spectrometric. The microstructure was examined using scanning electron microscopy (SEM). OVX had statistically higher averages (pxa0<xa00.05) for alkaline phosphatase activity in the serum. Therefore, our results demonstrated that the comparison of the OVX with the CTR showed no evidence of significant differences in the serum calcium and phosphorus levels (pxa0>xa00.05); however, OVX showed a significant weight gain (pxa0<xa00.0001) with a body mass increase of 30.23xa0±xa06.45xa0%. BMD results presented significant differences (pxa0=xa00.01985) between CTR and OVX. The total mass loss (TG) was 39.12xa0±xa00.45xa0% in OVX, while in CTR groups, it was the 32.45xa0±xa01.01xa0% (pxa0=xa00.0038). The results of the calcium amount in the bones of OVX (199.86xa0±xa08.08) were lower than the CTR (229.62xa0±xa010.02). SEM micrographs showed that OVX presented bone porosity, while CTR showed denser trabecular structure; this result corroborated with bone mass loss in OVX. The ovariectomy-induced bone loss in the rodent model can be evaluated using physical–chemical techniques based on thermal analysis, atomic absorption spectrometry and scanning electronic microscopy.