RESUMEN
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.
RESUMEN
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.
RESUMEN
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.
