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1.
ACS Omega ; 9(25): 27428-27437, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38947794

RESUMO

Recently, obtaining collagen films using a cross-linking technique has been a successful strategy. The current investigation used six cross-linker extracts (CE) from six different pomegranate varieties' byproducts to make and characterize collagen-tannin films using acid-soluble collagen (SC). The polymeric film has a yellow hue after CE incorporation. Fourier transform infrared spectroscopy assessed the impact of CE and its successful interaction within the matrix. The shifts verify different interactions between extracts and collagen functional groups, where they likely form new hydrogen bonds, retaining their helix structure without damaging the matrix. Scanning electron microscopy was used to analyze the morphology and fiber size. The average diameter of the fibers was found to be about 3.64 µm. Thermal behaviors (denaturation and degradation) were investigated by thermogravimetric analysis. The weight losses of cross-linked films increased by around 20% compared to non-cross-linked ones. This phenomenon was explained by the absence of telopeptide sections in the collagen helical structure, typically reinforced by lysine and hydroxylysine covalent linkages. Nanoscaled observations were also accomplished using transmission electron microscopy (TEM) on SC and SC-CE. The TEM analysis confirmed the CE polymerization degree effect on the cross-linking density via the overlap sequences, ranging up to 32.38 ± 2.37 nm on the fibril. The prepared biodegradable collagen-tannin film showed higher cross-linking density, which is expected to improve the biomaterial applications of collagen films while exploiting the underrated pomegranate byproducts.

2.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 2): 232-239, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38333114

RESUMO

The in-do-line portion of the title mol-ecule, C16H13NO2, is planar. In the crystal, a layer structure is generated by C-H⋯O hydrogen bonds and C-H⋯π(ring), π-stacking and C=O⋯π(ring) inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (43.0%), H⋯C/C⋯H (25.0%) and H⋯O/O⋯H (22.8%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. The volume of the crystal voids and the percentage of free space were calculated to be 120.52 Å3 and 9.64%, respectively, showing that there is no large cavity in the crystal packing. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the stabilization is dominated by the dispersion energy contributions in the title compound. Moreover, the DFT-optimized structure at the B3LYP/6-311G(d,p) level is compared with the experimentally determined mol-ecular structure in the solid state.

3.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 11): 1033-1036, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37936861

RESUMO

In the title compound, C20H28BrNO2, the indoline portion is almost planar and the 12-bromo-dodecyl chain adopts an all-trans conformation apart from the gauche terminal C-C-C-Br fragment. A micellar-like structure is generated in the crystal by C-H⋯O hydrogen bonds and π-stacking inter-actions between indolinedione head groups and inter-calation of the 12-bromo-dodecyl tails. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (58.9%), H⋯O/O⋯H (17.9%) and H⋯Br/Br⋯H (9.5%) contacts. A density functional theory (DFT) optimized structure at the B3LYP/ 6-311 G(d,p) level shows good agreement with the experimentally determined mol-ecular structure in the solid state.

4.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 10): 895-898, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37817954

RESUMO

The asymmetric unit of the title compound, C12H13N3O4, consists of two mol-ecules differing to a small degree in their conformations. In the crystal, layers of mol-ecules are connected by weak C-H⋯O hydrogen bonds and slipped π-stacking inter-actions. These layers lie parallel to (10) and are stacked along the normal to that plane. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing arise from H⋯H (43.5%) and H⋯O/O⋯H (30.8%) contacts. The density functional theory (DFT) optimized structure of the title compound at the B3LYP/ 6-311 G(d,p) level agrees well with the experimentally determined mol-ecular structure in the solid state.

5.
Molecules ; 27(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35744970

RESUMO

Pomegranate variety properties are important not only to demonstrate their diversity but also to satisfy the current market need for high-quality fruits. This study aims to characterize pomological and physico-chemical features as well as the antioxidant capacity of Moroccan local cultivars (Djeibi, Mersi, Sefri 1 and Sefri 2) compared to the imported ones (Mollar de Elche and Hicaz). The pomological characteristics of varieties were relatively diverse. The juice varieties (PJ) displayed a marketed variability in organoleptic and quality properties, such as the flavor, juice yield, and micro/macronutrients contents. Interrelationships among the analyzed properties and PJ varieties were investigated by principal component analysis (PCA). Dimension of the data set was reduced to two components by PCA accounting for 64.53% of the variability observed. The rinds varieties (PR) were studied for their total phenolics, flavonoids, and condensed tannins quantifications. PR varieties extracts exhibited different levels of free radical scavenging activity and local varieties revealed a greater potential with stability over time. The HPLC-DAD analyses of PR extracts revealed (+) catechin as the major compound, where the highest content was found for the local varieties. The SEC analysis showed the molecular weight distribution of phenolic compounds with a high size of condensed tannins formed by the polymerization of the catechin monomer. Given these properties, this research provides an easy selection of high-quality fruits as potential candidates for local market needs.


Assuntos
Catequina , Lythraceae , Punica granatum , Proantocianidinas , Antioxidantes/química , Catequina/análise , Frutas/química , Lythraceae/química , Marrocos , Fenóis/análise , Extratos Vegetais/química , Proantocianidinas/análise , Sensação
6.
Acta Crystallogr E Crystallogr Commun ; 78(Pt 4): 425-432, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35492275

RESUMO

In the title compound, C12H10ClNO3, the di-hydro-quinoline moiety is not planar with a dihedral angle between the two ring planes of 1.61 (6)°. An intra-molecular C-H⋯O hydrogen bond helps to establish the rotational orientation of the carboxyl group. In the crystal, sheets of mol-ecules parallel to (10) are generated by C-H⋯O and C-H⋯Cl hydrogen bonds, and are stacked through slipped π-stacking inter-actions between inversion-related di-hydro-quinoline units. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (34.2%), H⋯O/O⋯H (19.9%), H⋯Cl/Cl⋯H (12.8%), H⋯C/C⋯H (10.3%) and C⋯C (9.7%) inter-actions. Computational chemistry indicates that in the crystal, the C-H⋯Cl hydrogen-bond energy is -37.4 kJ mol-1, while the C-H⋯O hydrogen-bond energies are -45.4 and -29.2 kJ mol-1. An evaluation of the electrostatic, dispersion and total energy frameworks revealed that the stabilization is dominated via the dispersion energy contribution. Density functional theory (DFT) optimized structures at the B3LYP/6-311 G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state, and the HOMO-LUMO behaviour was elucidated to determine the energy gap.

7.
RSC Adv ; 12(7): 4175-4186, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35425412

RESUMO

An environmental approach for leather manufacturing is primordial to provide a global strategy towards more sustainable biomaterials and greener tanning processing methods. The ability of collagen as a principal component of skin to combine natural phenolic compounds, especially vegetable tannins, has been proven to be eco-friendly and manageable, while making good improvement to leather properties in the tanning process. In this study, we have used pomegranate phenolic compounds and insoluble collagen as a model system to examine the effects of tanning steps on the conformation of collagen. In detail, efficient modified extraction of pure insoluble collagen (IC) was presented. The IC was successfully identified using XRD, FTIR, SEM-EDS and TGA-DSC to verify the triple helix structure, morphology and thermal properties. As a result, the as-extracted collagen exhibits a high purity, preserving the triple helix collagen structure. Besides, the IC was modified using extracted pomegranate phenolic compounds, resulting in Crosslinked Insoluble Collagen (CIC). Characterization techniques were also performed to confirm the crosslinking process. Indeed, by comparing the FTIR vibrational spectra of IC and CIC, slight shifts of amide groups were observed, indicating the presence of inter and intramolecular interaction between IC functional groups and pomegranate phenolic compounds. Moreover, the morphology of CIC was changed. XRD analysis confirms collagen conformational integrity. Finally, thermal properties were improved. The temperature at 50% weight loss (T°50) increases from 344.54 °C to 375.53 °C. CIC multifunctionality allowed utilizing pomegranate phenolic compound extracts as a tanning agent in leather processing.

8.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 8): 1296-1301, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32844017

RESUMO

The asymmetric unit of the title compound, C11H12N2O2·H2O, contains a mol-ecule of 1,4,6-trimethyl-1,4-di-hydro-quinoxaline-2,3-dione and a solvent water mol-ecule. Four atoms of the benzene ring are disordered over two sets of sites in a 0.706 (7):0.294 (7) ratio while the N-bound methyl groups are rotationally disordered with occupancy ratios of 0.78 (4):0.22 (4) and 0.76 (5):0.24 (5). In the crystal, mol-ecules are linked by O-H⋯O and C-H⋯O hydrogen bonds into layers lying parallel to (10). The Hirshfeld surface analysis indicates that the most important contributions to the packing arrangement are due to H⋯H (51.3%) and O⋯H/H⋯O (28.6%) inter-actions. The mol-ecular structure calculated by density functional theory is compared with the experimentally determined mol-ecular structure, and the HOMO-LUMO energy gap has been calculated.

9.
ScientificWorldJournal ; 2019: 2630537, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885523

RESUMO

Snails were fed with three medicinal plants belonging to the Lamiaceae family (rosemary, sage, and peppermint) in order to test their effects on those animals with high nutritive values. The media of raising were flour containing different percentages of the cited plants ranging from 1% to 9%. The feed had benefits on the raised snails depending on the plant and its percentage. Minerals in those aromatic plants, especially zinc and magnesium, had their effect on protein synthesis in snails fed with those plant percentages. Rosemary was the most profitable plant with the highest protein amount, the lowest mortality rate, and reduced microbial charge. Furthermore, it was a good regulator of the specific catalase activity which confirmed the role of the antioxidant activity of rosemary during raising snails.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Plantas Medicinais/química , Caramujos/crescimento & desenvolvimento , Agricultura/métodos , Animais , Magnésio/análise , Mentha piperita/química , Rosmarinus/química , Salvia officinalis/química , Caramujos/fisiologia , Zinco/análise
10.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 10): 1411-1417, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31636967

RESUMO

The title compound, C15H12ClNO3, consists of a 1,2-di-hydro-quinoline-4-carb-oxyl-ate unit with 2-chloro-ethyl and propynyl substituents, where the quinoline moiety is almost planar and the propynyl substituent is nearly perpendicular to its mean plane. In the crystal, the mol-ecules form zigzag stacks along the a-axis direction through slightly offset π-stacking inter-actions between inversion-related quinoline moieties which are tied together by inter-molecular C-HPrpn-yl⋯OCarbx and C-HChlethy⋯OCarbx (Prpnyl = propynyl, Carbx = carboxyl-ate and Chlethy = chloro-eth-yl) hydrogen bonds. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (29.9%), H⋯O/O⋯H (21.4%), H⋯C/C⋯ H (19.4%), H⋯Cl/Cl⋯H (16.3%) and C⋯C (8.6%) 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, the C-HPrpn-yl⋯OCarbx and C-HChlethy⋯OCarbx hydrogen bond energies are 67.1 and 61.7 kJ mol-1, respectively. Density functional theory (DFT) optimized structures at the B3LYP/ 6-311 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.

11.
Chemistry ; 24(66): 17449-17453, 2018 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30169893

RESUMO

An original metal-free procedure for the synthesis of biarylmethanes is disclosed herein. The reactions occur with high selectivity starting from aryl iodides and benzylic ketones in the presence of superbasic media (CsOH/DMSO). This procedure allows a straightforward access to a wide range of biarylmethane derivatives substituted with electron-withdrawing and -donating substituents.

12.
PLoS One ; 11(9): e0161751, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27644093

RESUMO

Orange (Citrus sinensis) and grapefruit (Citrus paradise) peels were used as a source of pectin, which was extracted under different conditions. The peels are used under two states: fresh and residual (after essential oil extraction). Organic acid (citric acid) and mineral acid (sulfuric acid) were used in the pectin extraction. The aim of this study is the evaluation the effect of extraction conditions on pectin yield, degree of esterification "DE" and on molecular weight "Mw". Results showed that the pectin yield was higher using the residual peels. Moreover, both peels allow the obtainment of a high methoxyl pectin with DE >50%. The molecular weight was calculated using Mark-Houwink-Sakurada equation which describes its relationship with intrinsic viscosity. This later was determined using four equations; Huggins equation, kramer, Schulz-Blaschke and Martin equation. The molecular weight varied from 1.538 x1005 to 2.47x1005 g/mol for grapefruit pectin and from 1.639 x1005 to 2.471 x1005 g/mol for orange pectin.


Assuntos
Citrus paradisi/química , Citrus sinensis/química , Pectinas/química , Extratos Vegetais/química , Ácido Cítrico/química , Esterificação , Frutas/química , Pectinas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Ácidos Sulfúricos/química , Viscosidade
13.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 2): o229, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24764928

RESUMO

The structure of the title compound, C20H29NO2, is isotypic to that of its homologue 1-octylindoline-2,3-dione. The indoline ring and the two carbonyl-group O atoms are approximately coplanar, the largest deviation from the mean plane being 0.0760 (10) Å. The mean plane through the fused-ring system is nearly perpendicular to the mean plane passing through the 1-dodecyl chain [dihedral angle = 77.69 (5)°]. All C atoms of the dodecyl group are in an anti-periplanar arrangement. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming a three-dimensional network.

14.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 3): o360, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24765046

RESUMO

The structure of the title compound, C11H7NO2, is isotypic to that of its homologue, 1-octylindoline-2,3-dione [Qachchachi et al. (2013 ▶). Acta Cryst. E69, o1801]. The indoline ring and the two carbonyl O atoms are approximately coplanar, the largest deviation from the mean plane being 0.021 (1) Šfor one of the O atoms. The mean plane through the fused ring system is nearly perpendicular to the propynyl group, as indicated by the N-C-C-C torsion angle of 77.9 (1)°. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds and π-π inter-actions between benzene rings [inter-centroid distance = 3.5630 (10) Å], forming a three-dimensional structure.

15.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 1): o119, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23476381

RESUMO

The benzimidazolone part of the title mol-ecule, C10H8N2O, is almost planar [r.m.s. deviation = 0.014 (1) Å] and the NCH2C CH group forms a dihedral angle of 67.95 (6)° with its best plane. In the crystal, mol-ecules form inversion dimers via pairs of N-H⋯O hydrogen bonds. C-H⋯O inter-actions connect the dimers, forming a two-dimensional polymeric network parallel to (100).

16.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 1): o122, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23476384

RESUMO

In the title compound, C15H14N2O, the fused five- and six-membered ring system is essentially planar, the maximum deviation from the mean plane being 0.009 (1) Å. The benzimidazol-2(3H)-one residue is nearly perpendicular to the benzyl ring, forming a dihedral angle of 77.41 (6)°. In the crystal, inversion dimers are formed by pairs of N-H⋯O hydrogen bonds; these dimers are linked by weak C-H⋯O inter-actions into a two-dimensional array in the (102) plane.

17.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): o3069, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23284403

RESUMO

In the title compound, C(19)H(30)N(2)O, the fused ring system is essentially planar, the maximum deviation from the mean plane being 0.013 (2) Šfor the N atom bearing the dodecyl chain. The 1-dodecyl group is almost perpendicular to the 1H-benzo[d]imidazol-2(3H)-one plane as indicated by the dihedral angle of 82.9 (2)°between planes through the fused ring system and the first three C atoms of the chain. The C-C-C-C torsion angles (about ±179°) of the dodecyl group indicate an anti-periplanar conformation. In the crystal, inversion dimers are formed by pairs of N-H⋯O hydrogen bonds.

18.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): o3212, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23284519

RESUMO

The fused five- and six-membered rings in the title compound, C(10)H(10)N(2)O, are approximately coplanar, with an r.m.s. deviation of 0.008 Å. The mean plane of the allyl group is roughly perpendicular to the mean plane of the 1,3-benzimidazol-2(3H)-one system, making a dihedral angle of 86.1 (2)°. In the crystal, each mol-ecule is linked to its symmetry equivalent partner by a pair of N-H⋯O and C-H⋯O hydrogen bonds.

19.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 12): o3234, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22199747

RESUMO

In the mol-ecular structure of the title compound, C(21)H(18)N(2)O, the fused-ring system is essentially planar, the largest deviation from the mean plane being 0.0121 (9) Å. The O atom and adjacent C atom are located in Wyckoff position 4e on a twofold axis (0, y, 1/4). The two benzyl groups are almost perpendicular to the benzimidazole plane, but point in opposite directions. The dihedral angle between the benzimidazole mean plane and the phenyl ring is 81.95 (5)°, whereas that between the two benzyl groups is 60.96 (7)°.

20.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 12): o3340-1, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22199836

RESUMO

The asymmetric unit of the title compound, C(16)H(23)ClN(2)O, comtains two independent mol-ecules in which the fused-ring systems are essentially planar, the largest deviation from the mean plane of each mol-ecule being 0.011 (2) Šand 0.016 (2) Å. The benzimidazole rings of the two mol-ecules make a dihedral angle of 66.65 (7)°. The nonyl substituents are almost perpendicular to the benzimidazole planes [C-N-C-C tosrsion angles = 96.0 (3) and 81.0 (2)°]. In the crystal, each independent molecule forms an inversion dimer via a pair of N-H⋯O hydrogen bonds. In one of the independent molecules, the terminal -CH(2)-CH(3) group of the alkyl chain is disordered over two sets of sites with a refined occupancy ratio of 0.746 (7):0.254 (7).

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