ABSTRACT
This study evaluated the presence of the three pesticides methomyl (MET), carbendazim (CBZ) and chlorpyrifos-ethyl (CPE), as well as the degradation product of CPE (3,5,6-trichloro-2-pyridinol; TCP), in 44 honey samples from all 12 regions of Morocco. With a validated HPLC-UV method occurrence frequencies of 63.6% for MET, 54.5% for CBZ, 95.1% for CPE and 34.1% for TCP were obtained, even at concentrations higher than the maximum residue limits for MET, CPE and TCP. Based on the predominant pesticide, principal component analysis separated sampling regions into three groups. Risk assessment indicated that ingestion of these pesticides, alone or in combination, in honey did not pose a risk to consumers (HQ and HI < 1).
Subject(s)
Food Contamination , Honey , Pesticide Residues , Honey/analysis , Morocco , Pesticide Residues/analysis , Food Contamination/analysis , Humans , Risk Assessment , Chromatography, High Pressure Liquid , Principal Component Analysis , Carbamates/analysis , Chlorpyrifos/analysis , BenzimidazolesABSTRACT
The objective of this study was to identify the major compounds present in Cedar tar obtained by distillation of Cedrus atlantica wood from the Taza forest (Morocco) and to evaluate its antidermatophytic activity in vitro against the three strains of dermatophytes most widespread in Morocco, considered the main prevailing causes of fungal infections of the skin, hair and nails. GC/MS analysis revealed that cedar tar is composed mainly of hydrocarbon sesquiterpenes and oxygenated sesquiterpenes, with nine major compounds identified, including α-Cedrene, ß-Cadinene, γ-Cadinene, ß-Himachelene, α-Turmerone, ß-Turmerone, Ar-tumerone, α-Atlantone and Himachalol. The evaluation of antifungal activity was carried out by the micro dilution technique. The MIC values found were 100µg/mL, 2µg/mL and 0.1µg/mL on Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum canis strains respectively. The observed strong antifungal activity of cedar tar is attributed to the prevalence of oxygenated and hydrocarbon sesquiterpenes, known for their established antidermatophytic properties. This study highlights the potential of the Atlas Cedar tar as an effective antifungal agent for the treatment of superficial mycoses, particularly dermatophytoses.
Subject(s)
Antifungal Agents , Arthrodermataceae , Cedrus , Microbial Sensitivity Tests , Microsporum , Microsporum/drug effects , Antifungal Agents/pharmacology , Antifungal Agents/isolation & purification , Arthrodermataceae/drug effects , Cedrus/chemistry , Sesquiterpenes/pharmacology , Sesquiterpenes/isolation & purification , Plant Extracts/pharmacology , Plant Extracts/chemistry , Gas Chromatography-Mass Spectrometry , Phytochemicals/pharmacology , Phytochemicals/isolation & purification , Phytochemicals/analysis , Phytochemicals/chemistry , MoroccoABSTRACT
This study aims to encapsulate the fungicide carbendazim using a biodegradable polymer (pectin). First, we have obtained calcium pectinate beads (CPG-Carb) by ionotropic gelation using calcium ions as a crosslinking agent. These beads were then coated with silica starting from tetraethoxysilane (TEOS), by a sol-gel process to form hybrid beads (CPG-Carb-SG). The morphology, composition and structure of both beads were characterized and the controlled release assays of the fungicide were studied in both water and soil columns. The encapsulation efficiency for CPG-Carb was slightly higher (75%) compared to CPG-Carb-SG (67%) due to carbendazim loss during the impregnation and condensation steps. The release rate in water and soil columns was about 4 times lower for CPG-Carb-SG than CPG-Carb demonstrating the efficiency of the silica coating to delay the release of carbendazim. Moreover, the release of CPG-Carb-SG is due to the erosion of the silica layer during the first two weeks. After this period, the silica layer was degraded, and the release is then controlled by the swelling of the organic part of the bead as observed for CPG-Carb. Finally, the biodegradability of the pectin, and the release profile make such systems promising candidates for sustained and economical pesticide delivery systems.
Subject(s)
Pectins , Silicon Dioxide , Benzimidazoles , Carbamates , Soil , WaterABSTRACT
It is of interest to study the binding capacity of "3-[2-(2-Amino-1H-benzo[d]imidazol-1-yl)ethyl]-1,3-oxazolidin-2-one" (OXB2) with the active site of gamma-aminobutyric acid (GABA) located in the GABA type A receptor (GABAAR) in comparison with different GABAA subtypes. Optimal binding features were observed with the α2ß2γ2 isoform (-8 kcal/mol). This is similar (-7.3 and -7.2 kcal/mol, respectively) for subtypes (α3ß2γ2 and α1ß2γ2). This implies that OXB2 binds preferentially to subtypes associated with anxiety (α2- and/or α3-containing receptors) linked molecules than with the subtype associated with sedation (α1-containing receptors). It is further noted that molecular dynamics simulation data of the complex (OXB2-GABAAR) shows adequate structural stability in aqueous environment. Moreover, relevant ADMET data is found adequate for further consideration.
ABSTRACT
In the title mol-ecule, C12H13N3O2S, the benzo-thia-zine moiety is slightly non-planar, with the imidazolidine portion twisted only a few degrees out of the mean plane of the former. In the crystal, a layer structure parallel to the bc plane is formed by a combination of O-HHydethyâ¯NThz hydrogen bonds and weak C-HImdzâ¯OImdz and C-HBnzâ¯OImdz (Hydethy = hy-droxy-ethyl, Thz = thia-zole, Imdz = imidazolidine and Bnz = benzene) inter-actions, together with C-HImdzâ¯π(ring) and head-to-tail slipped π-stacking [centroid-to-centroid distances = 3.6507â (7) and 3.6866â (7)â Å] inter-actions between thia-zole rings. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from Hâ¯H (47.0%), Hâ¯O/Oâ¯H (16.9%), Hâ¯C/Câ¯H (8.0%) and Hâ¯S/Sâ¯H (7.6%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Computational chemistry indicates that in the crystal, C-Hâ¯N and C-Hâ¯O hydrogen-bond energies are 68.5 (for O-HHydethyâ¯NThz), 60.1 (for C-HBnzâ¯OImdz) and 41.8â kJâ mol-1 (for C-HImdzâ¯OImdz). Density functional theory (DFT) optimized structures at the B3LYP/6-311â G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state.
ABSTRACT
The title compound, C18H12FNOS, is built up from a 4-fluoro-benzyl-idene moiety and a di-hydro-benzo-thia-zine unit with a propynyl substituent, with the heterocyclic portion of the di-hydro-benzo-thia-zine unit adopting a shallow boat conformation with the propynyl substituent nearly perpendicular to it. The two benzene rings are oriented at a dihedral angle of 43.02â (6)°. In the crystal, C-HFlurphenâ¯FFlurphen (Flurphen = fluoro-phen-yl) hydrogen bonds link the mol-ecules into inversion dimers, enclosing R 2 2(8) ring motifs, with the dimers forming oblique stacks along the a-axis direction. Hirshfeld surface analysis of the crystal structure indicates that the most important contributions to the crystal packing are from Hâ¯H (33.9%), Hâ¯C/Câ¯H (26.7%), Hâ¯F/Fâ¯H (10.9%) and Câ¯C (10.6%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Density functional theory (DFT) optimized structures at the B3LYP/6-311â G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.
ABSTRACT
The title compound, C(16)H(10)N(2)S, is almost planar (r.m.s. deviation for all non-H atoms = 0.080â Å). The dihedral angle between the three fused-ring system and the phenyl ring is 9.26â (3)°. The S atom and the opposite C atom of the thio-phene ring are mutually disordered with an occupancy ratio of 0.7706â (19):0.2294â (19).
ABSTRACT
In the crystal structure of the title compound, C(22)H(18)N(4)O, the quinoxaline system makes dihedral angles of 86.59â (7) and 63.37â (9)° with the benzohydrazide and phenyl rings, respectively. The benzohydrazide ring makes a dihedral angle of 72.46â (10)° with the phenyl ring. The crystal structure is stabilized by inter-molecular N-Hâ¯O hydrogen bonds, C-Hâ¯O contacts and C-Hâ¯π inter-actions.
ABSTRACT
In the title compound, C(18)H(15)N(3)O(2), the dihedral angle between the ring systems is 15.1â (1)°. The amino H atom is hydrogen bonded to the exocyclic O atom of the five-membered ring, forming an S(6) motif.
ABSTRACT
The asymmetric unit of the title compound, C(16)H(14)N(2)O, contains three independent mol-ecules. The dihedral angles between the quinoxaline and phenyl planes in the three mol-ecules are 82.58â (8), 85.66â (9) and 85.36â (9)°. The crystal packing is stabilized by C-Hâ¯O and C-Hâ¯N hydrogen bonds.
ABSTRACT
In the title compound, C(12)H(13)N(3)O(2)S, the oxazolidin ring displays an envelope conformation. The dihedral angle between the benzimidazole ring and the 1,3-oxazolidin-2-one mean plane is 69.85â (13)°. In the crystal, mol-ecules are linked by inter-molecular N-Hâ¯N hydrogen bonds, forming a chain parallel to the b axis.
ABSTRACT
Two solid catalysts in which a chiral copper(II) bisoxazoline has been covalently anchored on silica and MCM-41 have been prepared; the solids are enantioselective catalysts (up to 92% ee) for the Friedel-Crafts hydroxyalkylation of 1,3-dimethoxybenzene with 3,3,3-trifluoropyruvate.