Preparation and Characterization of a Novel Salicin-Cyclodextrin Complex.

Bioactive compounds extracted from plants can provide wide health benefits. However, some molecules have limited applications as pharmaceuticals due to their limited solubility, poor bioavailability, and low stability when exposed to environmental factors. Their integration in formulations that can deliver them to physiological targets while preserving their biological activity can enhance their usage in improving human health. This research provides a delivery system design to enhance the solubility, stability and to mask the bitter taste of salicin. Thus, a novel salicin-ß-cyclodextrin complex was prepared and analyzed by X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, FTIR, Raman and UV-Vis spectroscopy. The analytical and computational methods provided clear and distinct evidence for inclusion of salicin within the ß-cyclodextrin cavity and brought important findings for the characterization of the inclusion complex. The present study showed that salicin and ß-cyclodextrin can form inclusion complexes, both in solution and in solid state, and that the inclusion of salicin in the cavity of ß-cyclodextrin leads to the improvement of its solubility and stability. Thus, the study communicates both qualitative and quantitative knowledge about the preparation of a new salicin-ß-cyclodextrin inclusion complex suggesting its potential applications in pharmaceutical industry and medical sciences, as formulations with better compliance for the patient, with increased bioavailability, and easier control of dosage.

Some Brassicaceae Extracts as Potential Antioxidants and Green Corrosion Inhibitors.

Glucosinolates-rich extracts of some Brassicaceae sources, such as broccoli, cabbage, black radish, rapeseed, and cauliflower, were obtained using an eco-friendly extraction method, in a microwave field, with 70% ethanol, and evaluated in order to establish their in vitro antioxidant activities and anticorrosion effects on steel material. The DPPH method and Folin-Ciocâlteu assay proved good antioxidant activity (remaining DPPH, 9.54-22.03%) and the content of total phenolics between 1008-1713 mg GAE/L for all tested extracts. The electrochemical measurements in 0.5 M H2SO4 showed that the extracts act as mixed-type inhibitors proving their ability to inhibit corrosion in a concentration-dependent manner, with a remarkable inhibition efficiency (92.05-98.33%) achieved for concentrated extracts of broccoli, cauliflower, and black radish. The weight loss experiments revealed that the inhibition efficiency decreased with an increase in temperature and time of exposure. The apparent activation energies, enthalpies, and entropies of the dissolution process were determined and discussed, and an inhibition mechanism was proposed. An SEM/EDX surface examination shows that the compounds from extracts may attach to the steel surface and produce a barrier layer. Meanwhile, the FT-IR spectra confirm bond formation between functional groups and the steel substrate.

Properties and Bioapplications of Amphiphilic Janus Dendrimers: A Review.

Amphiphilic Janus dendrimers are arrangements containing both hydrophilic and hydrophobic units, capable of forming ordered aggregates by intermolecular noncovalent interactions between the dendrimer units. Compared to conventional dendrimers, these molecular self-assemblies possess particular and effective attributes i.e., the presence of different terminal groups, essential to design new elaborated materials. The present review will focus on the pharmaceutical and biomedical application of amphiphilic Janus dendrimers. Important information for the development of novel optimized pharmaceutical formulations, such as structural classification, synthetic pathways, properties and applications, will offer the complete characterization of this type of Janus dendrimers. This work will constitute an up-to-date background for dendrimer specialists involved in designing amphiphilic Janus dendrimer-based nanomaterials for future innovations in this promising field.

Novel Chloro-Substituted Salicylanilide Derivatives and Their ß-Cyclodextrin Complexes: Synthesis, Characterization, and Antibacterial Activity.

The goal of this research was to design novel chloro-substituted salicylanilide derivatives and their ß-cyclodextrin complexes in order to obtain efficient antibacterial compounds and to demonstrate the beneficial role of complexation on the efficiency of these compounds. Thus, salicylanilide derivatives, esters, and hydrazides were obtained by microwave-assisted synthesis and their structure proven based on FTIR and NMR spectra. In order to improve water solubility, chemical and physical stability, and drug distribution through biological membranes, the inclusion complexes of the ethyl esters in ß-cyclodextrin were also obtained using kneading. Inclusion-complex characterization was accomplished by modern analytical methods, X-ray diffraction, SEM, TGA, FTIR, and UV-vis spectroscopy. The newly synthesized compounds were tested against some Gram-positive and Gram-negative bacteria. Antimicrobial tests revealed good activity on Gram-positive bacteria and no inhibition against Gram-negative strains. The MIC and MBC values for compounds derived from N-(2-chlorophenyl)-2-hydroxybenzamide were 0.125-1.0 mg/mL. N-(4-chlorophenyl)-2-hydroxybenzamide derivatives were found to be less active. The inclusion complexes generally behaved similarly to the guest compounds, and antibacterial activity was not been altered by complexation.

A computational study of the interactions between anthocyans and cyclodextrins.

The interactions between six anthocyans (cyanidin-3-O-glucoside, delphinidin-3-O-glucoside, malvidin-3-O-glucoside, cyanidin-3-O-rutinoside, delphinidin-3-O-rutinoside, malvidin-3-O-rutinoside) and cyclodextrins were investigated by means of computational techniques. Four different structures of the aforementioned anthocyans were considered, as a result of the dependence structure - pH value (flavylium cations in acidic medium, hemiketals in neutral solutions and two tautomeric quinones in alkaline environment). The results outlined that the anthocyanidin-3-O-rutinoside are favored for the obtaining of inclusion complexes with the cyclodextrins, mostly due to the larger number of OH groups involved in the formation of hydrogen bonds. For all the four types of structures, best results have been obtained for ß- and γ-cyclodextrins.

Anti-hyperglycemic effect of bilberry, blackberry and mulberry ultrasonic extracts on diabetic rats.

Small fruits like bilberry, blackberry and mulberry are rich sources of anthocyanins and other phenols, compounds with a certified antioxidant activity and spectacular effects in some chronic diseases. Romanian bilberry, blackberry and mulberry extracts were tested as anti-hyperglycemic agents on diabetic rats. Anthocyanins extraction was carried out with 80 % acidified ethanol in ultrasonically conditions at 23 ± 2 °C and 40 kHz. Monomeric anthocyanins content was determined by pH differential method and varied between 1200 and 2800 mg/L. The analyses of anthocyanins were achieved using high performance liquid chromatography and mass spectrometry. Phenolics content was determined by Folin-Ciocalteu procedure and values varied between 2320 and 4250 mg/L gallic acid. Antioxidant activities of extracts were estimated by DPPH scavenging method and the values varied between 8 and 16 miliequivalents Trolox. In order to evaluate the toxicology of the extracts, the heavy metals concentration and pesticides content were analyzed. The extracts were administrated to diabetic rats in drinking water for five weeks. The administration of bilberry extract offered no satisfactory results. Treatment with blackberry extract determined a significant decrease of glucose level from 360 to about 270 mg/dL (p < 0.05). The mulberry extract administration determined a significant decrease of glucose level from 252 mg/dL at the start day to 155 mg/dL at the final of experiment (p < 0.05).