Antibacterial and antioxidant activities of a novel biosynthesized selenium nanoparticles using Rosa roxburghii extract and chitosan: Preparation, characterization, properties, and mechanisms.

Developing efficient and safe antibacterial agents to inhibit pathogens including Physalospora piricola and Staphylococcus aureus is of great importance. Herein, a novel compound composed of Rosa roxburghii procyanidin, chitosan and selenium nanoparticle (RC-SeNP) was bio-synthesized, with the average diameter and zeta potential being 84.56 nm and -25.60 mV, respectively. The inhibition diameter of the RC-SeNP against P. piricola and S. aureus reached 18.67 mm and 13.13 mm, and the maximum scavenging activity against DPPH and ABTS reached 96.02% and 98.92%, respectively. Moreover, the RC-SeNP completely inhibited the propagation P. piricola and S. aureus on actual apples, suggesting excellent in vivo antimicrobial capacity. The transcriptome analysis and electron microscope observation indicated that the antibacterial activity would be attributed to adhering to and crack the cell walls as well as damage the cytomembrane and nucleus. Moreover, the RC-SeNP effectively maintained the vitamin C, total acid, and water contents of red bayberry, demonstrating potential application for fruit preservation. At last, the RC-SeNP showed no cell toxicity and trace selenium residual dose (0.03 mg/kg on apple, 0.12 mg/kg on red bayberry). This study would enlighten future development on novel nano-bioantibacterial agents for sustainable agriculture.

Fucosylated chondroitin sulfate from sea cucumber improves glucose metabolism and activates insulin signaling in the liver of insulin-resistant mice.

This study investigated the effects of fucosylated chondroitin sulfate (CHS) isolated from sea cucumber on glucose metabolism and insulin signaling in the liver of insulin-resistant C57BL/6 mice fed a high-fat, high-sucrose diet (HFSD). Male C57BL/6J mice were randomly assigned into six groups: control; HFSD; 1 mg RSG/kg·body weight (RSG); 80 mg CHS/kg · body weight (CHS); 20 mg CHS+1 mg RSG/kg · body weight (20 CHS+RSG); and 80 mg CHS+1 mg RSG/kg · body weight (80 CHS+RSG). Blood glucose, insulin parameters, glucose metabolism-related enzymes activities and insulin-signaling transducers in the liver were analyzed at 19 weeks. Results showed that CHS significantly decreased body weight gain, adipose tissue weight, and fasting blood glucose and serum insulin levels in insulin-resistant mice. Rosiglitazone (RSG) is an effective thiazolidinedione hypoglycemic agent, and CHS synergistically enhanced the effect of RSG. CHS feeding normalized the activities of hexokinase, pyruvate kinase, glycogen phosphorylase, glucose-6-phosphatase, and increased glycogen reserves in the liver. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that CHS promoted the mRNA expression of insulin receptors (IR), insulin receptor substrate 2 (IRS-2), phosphatidylinositol 3 kinase (PI3K), protein kinase B (PKB), and glycogen synthase (GS) in the liver of insulin resistant mice, and inhibited glycogen synthase kinase-3 (GSK-3ß) mRNA expression. The results suggested that CHS treatment improved glucose metabolism by modulating metabolic enzymes and promoting the PI3K/PKB/GSK-3ß signaling pathway mediated by insulin at the transcriptional level. These results provided strong justification for the development of CHS as a functional food.

Poly[(µ(4)-tetra-zole-1-acetato-κN:N:O:O')silver(I)].

In the title complex, [Ag(C(3)H(3)N(4)O(2))](n), the Ag(I) atom is four-coordinated in a slightly distorted tetra-hedral coordination geometry by two N atoms from two tetra-zole-1-acetate (tza) ligands and two O atoms from the other two tza ligands. The tza ligand bridges two Ag atoms through the carboxyl-ate O atoms and simultaneously binds to the other two Ag atoms through the tetra-zole N atoms, forming a two-dimensional network parallel to (100).

Diaqua-bis-(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)nickel(II) tetra-hydrate.

In the title complex, [Ni(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·4H(2)O, the Ni(II) ion is coordinated in a slightly distorted octa-hedral environment formed by two bis-chelating H(2)pimda (H(3)pimda is 2-propyl-1H-4,5-dicarb-oxy-lic acid) ligands and two coordinated water mol-ecules. In the crystal structure, a three-dimensional framework is formed by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds involving the solvent water mol-ecules, coordinated water mol-ecules, carboxyl-ate O atoms and the protonated N atoms of the H(2)pimda ligands. The propyl groups of each H(2)pimda ligand are disordered over two sets of sites with refined occupancies of 0.50 (2):0.50 (2) and 0.762 (11):0.238 (11). In one water solvent mol-ecule, one of the H atoms was refined as disordered over two sites of equal occupancy.

Hexaaqua-nickel(II) 4,4'-(1,2-dihy-droxy-ethane-1,2-di-yl)dibenzoate monohydrate.

In the title compound, [Ni(H(2)O)(6)](C(16)H(12)O(6))·H(2)O, the Ni(II) cation is located on a mirror plane and is coordinated by six water mol-ecules, two of which are also located on the mirror plane, in a distorted octa-hedral geometry. The 4,4'-(1,2-dihy-droxy-ethane-1,2-di-yl)dibenzoate anion is centrosymmetric with the mid-point of the central ethane C-C bond located on an inversion center. The uncoordinated water mol-ecule is located on a mirror plane. Extensive O-H⋯O hydrogen bonding is present in the crystal structure.

Diaqua-bis-(4-carb-oxy-2-propyl-1H-imidazole-5-carboxyl-ato-κN,O)cobalt(II) N,N-dimethyl-formamide disolvate.

In the title complex, [Co(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·2C(3)H(7)NO, the Co(II) cation (site symmetry ) is six-coordinated by two 5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ate ligands and two water mol-ecules in a distorted octa-hedral environment. In the crystal structure, the complex mol-ecules and dimethyl-formamide solvent mol-ecules are linked by extensive O-H⋯O and N-H⋯O hydrogen bonding into sheets lying parallel to (21).

Tetra-aquabis(6-carboxy-1H-benzimid-azole-5-carboxyl-ato-κN)nickel(II) dimethyl-formamide disolvate dihydrate.

The title compound, [Ni(C(9)H(45)N(2)O(4))(2)(H(2)O)(4)]·2C(3)H(7)NO·2H(2)O, has the Ni(II) center coordinated by four water mol-ecules and two N atoms from two 1H-benzimidazole-5,6-dicarboxyl-ate ligands in an octa-hedral geometry. The mol-ecule inter-acts with the solvent water and dimethyl-formamide mol-ecules through N-H⋯O and O-H⋯O hydrogen bonds to form a three-dimensional supra-molecular network. The metal atom lies on a center of inversion.

Penta-aqua-(1H-benzimidazole-5,6-dicarboxyl-ato-κN)nickel(II) penta-hydrate.

In the title mononuclear complex, [Ni(C(9)H(4)N(2)O(4))(H(2)O)(5)]·5H(2)O, the Ni(II) atom is six-coordinated by one N atom from a 1H-benzimidazole-5,6-dicarboxyl-ate ligand and by five O atoms from five water mol-ecules and displays a distorted octa-hedral geometry. Inter-molecular O-H⋯O hydrogen-bonding inter-actions among the coordinated water mol-ecules, solvent water mol-ecules and carboxyl O atoms of the organic ligand and additional N-H⋯O hydrogen bonding lead to the formation of a three-dimensional supra-molecular network.

catena-Poly[[diaqua-(1,10-phenanthroline-κN,N')nickel(II)]-µ-1H-benzimidazole-5,6-dicarboxyl-ato-κN:O].

In the title complex, [Ni(C(9)H(4)N(2)O(4))(C(12)H(8)N(2))(H(2)O)(2)](n), the Ni(II) atom is hexa-coordinated by one N and one O atom from two different 1H-benzimidazole-5,6-dicarboxyl-ate ligands, two N atoms from one 1,10-phenanthroline ligand and two water mol-ecules. The flexible 1H-benzimidazole-5,6-dicarboxyl-ate ligands link the Ni(II) centres, forming an infinite zigzag chain parallel to [001]. The crystal packing is governed by inter-molecular hydrogen-bonding inter-actions of the O-H⋯O, N-H⋯O and C-H⋯O types.

Penta-aqua-(1H-benzimidazole-5,6-di-carboxyl-ato-κN)cobalt(II) penta-hydrate.

In the title mononuclear complex, [Co(C(9)H(4)N(2)O(4))(H(2)O)(5)]·5H(2)O, the Co(II) atom exhibits a distorted octa-hedral geometry involving an N atom of a 1H-benzimidazole-5,6-dicarboxyl-ate ligand and five water O atoms. A supra-molecular network is generated through inter-molecular O-H⋯O hydrogen-bonding inter-actions involving the coordinated and uncoordinated water mol-ecules and the carboxyl O atoms of the organic ligand. An inter-molecular N-H⋯O hydrogen bond is also observed.

Poly[diaqua-µ(2)-isonicotinato-µ(2)-oxalato-terbium(III)].

In the crystal structure of the title complex, [Tb(C(6)H(4)NO(2))(C(2)O(4))(H(2)O)(2)](n), the Tb(III) cation is coordinated by four O atoms from two oxalate ligands, two O atoms from two isonicotinate ligands and two O atoms from water mol-ecules within a distorted square-anti-prismatic coordination. The Tb(III) cation, the isonicotinate anion and the two crystallographically independent water mol-ecules occupy general positions, whereas one of the two crystallographically independent oxalate anions is located on a center of inversion, and the second oxalate anion is located on a twofold rotation axis. The Tb(III) cations are linked by the oxalate and isonicotinate anions into layers, which are connected via inter-molecular hydrogen-bonding and π-π stacking [with centroid-to-centroid distances of 3.509 (2) and 3.343 (3) Å] inter-actions into a three-dimensional network.