Pleurotus eryngii root waste and soybean meal co-fermented protein improved the growth, immunity, liver and intestinal health of largemouth bass (Micropterus salmoides).

The present study aimed to evaluate the effect of king oyster mushroom (Pleurotus eryngii) root waste and soybean meal co-fermented protein (CFP) on growth performance, feed utilization, immune status, hepatic and intestinal health of largemouth bass (Micropterus salmoides). Largemouth bass (12.33 ± 0.18 g) were divided into five groups, fed with diets containing 0 %, 5 %, 10 %, 15 % and 20 % CFP respectively for 7 weeks. The growth performance and dietary utilization were slightly improved by the supplementation of CFP. In addition, improved immunoglobulin M (IgM) content and lysozyme activity in treatments confirm the enhancement of immunity in fish by the addition of CFP, especially in fish fed 20 % CFP (P < 0.05). Furthermore, CFP significantly improved liver GSH (glutathione) content in groups D10 and D15 (P < 0.05), and slightly improved total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity while slightly reduced malondialdehyde (MDA) content. Simultaneously, the upregulation of lipolysis-related genes (PPARα, CPT1 and ACO) expression and downregulation of lipid synthesis-related genes (ACC and DGAT1) expression was recorded in the group D20 compared with the control (P < 0.05), which were consistent with the decreased liver lipid contents, suggests that lipid metabolism was improved by CFP. In terms of intestinal structural integrity, ameliorated intestinal morphology in treatments were consistent with the upregulated Occludin, Claudin-1 and ZO-1 genes expression. The intestinal pro-inflammatory cytokines (TNF-α and IL-8) expression were suppressed while the anti-inflammatory cytokines (IL-10 and TGF-ß) were activated in treatments. The expression of antimicrobial peptides (Hepcidin-1, Piscidin-2 and Piscidin-3) and intestinal immune effectors (IgM and LYZ) were slightly up-regulated in treatments. Additionally, the relative abundance of intestinal beneficial bacteria (Firmicutes) increased while the relative abundance of potential pathogenic bacteria (Fusobacterium and Proteobacteria) decreased, which indicated that the intestinal microbial community was well-reorganized by CFP. In conclusion, dietary CFP improves growth, immunity, hepatic and intestinal health of largemouth bass, these data provided a theoretical basis for the application of this novel functional protein ingredient in fish.

Ruthenium polyhydrides supported by rigid PCP pincer ligands: dynamic behaviour and reactions with CO2.

Two rigid ß-elimination immune PCcarbeneP pincer ligands, differing in their electron donor properties by variation of the substitution pattern on the aromatic linker arms, were complexed to ruthenium to form the dichlorides LRRuCl2 (R = H or NMe2). These compounds were converted to hydrido chlorides by treatment with dihydrogen (H2) and a base. By converting to tert-butoxide derivatives in situ under an atmosphere of H2, the poly hydride PCalkylP complexes LHRRu(H)3 compounds were generated. In these complexes, H2 has added across the RuC bond in the PCcarbeneP starting materials. The polyhydrides are dynamic in solution and extensive NMR studies helped to elucidate the speciation and fluxional processes operative in this dynamic system. The polyhydride complexes react rapidly with CO2 to give the PCcarbeneP formato hydride complexes LRRu(H)-κ2-O2CH. For R = H, the 1,2-hydride shift from the anchoring alkyl of the PCalkylP carbon to the metal is reversible, but for R = NMe2 it is irreversible. The CO2 incorporated into the formato ligand of these compounds exchanges with free CO2via a bimolecular mechanism that is more rapid for R = NMe2 than for R = H; plausible explanations for this observation are proffered. Experiments designed to evaluate the efficacy of the R = NMe2 formato hydride complex as a catalyst precursor for CO2 hydrogenation to formate salts reveal poor performance in comparison to state-of-the-art ruthenium-based catalysts. This is due primarily to the precipitation of a dimeric µ-κ2-κ1-CO3 carbonate complex that is not an active catalyst for the reaction.

Microporous Metal-Phosphonates with a Novel Orthogonalized Linker and Complementary Guests: Insights for Trivalent Metal Complexes from Divalent Metal Complexes.

The reliable self-assembly of microporous metal-phosphonate materials remains a longstanding challenge. This stems from, generally, more coordination modes for the functional group allowing more dense structures, and stronger bonding driving less crystalline products. Here, a novel orthogonalized aryl-phosphonate linker, 1,3,5-tris(4'-phosphono-2',6'-dimethylphenyl) benzene (H6 L3) has been used to direct formation of open frameworks. The peripheral aryl rings of H6 L3 are orthogonalized relative to the central aromatic ring giving a tri-cleft conformation of the linker in which small aromatic molecules can readily associate. When coordinated to magnesium ions, a series of porous crystalline metal-organic, and hydrogen-bonded metal-organic frameworks (MOFs, HMOFs) are formed (CALF-41 (Mg), HCALF-42 (Mg), -43 (Mg)). While most metal-organic frameworks are tailored based on choice of metal and linker, here, the network structures are highly dependent on the inclusion and structure of the guest aromatic compounds. Larger guests, and a higher stoichiometry of metal, result in increased solvation of the metal ion, resulting in networks with connectivities increasingly involving hydrogen-bonds rather than direct phosphonate coordination. Upon thermal activation and aromatic template removal, the materials exhibit surface areas ranging from 400-600 m2 /g. Self-assembly in the absence of aromatic guests yields mixtures of phases, frequently co-producing a dense 3-fold interpenetrated structure (1). Interestingly, a series of both more porous (530-900 m2 /g), and more robust solids is formed by complexing with trivalent metal ions (Al, Ga, In) with aromatic guest; however, these are only attainable as microcrystalline powders. The polyprotic nature of phosphonate linkers enables structural analogy to the divalent analogues and these are identified as CALF-41 analogues. Finally, insights to the structural transformations during metal ion desolvation in this family are gained by considering a pair of structurally related Co materials, whose hydrogen-bonded (HCALF-44 (Co)) and desolvated (CALF-44 (Co)) coordination bonded networks were fully structurally characterized.

Rhenium(I)-tricarbonyl complexes with methimazole and its selenium analogue: Syntheses, characterization and cell toxicity.

This study explores the effect of a thione/selone ligand on the cell toxicity (in vitro) and light activity of diimine Re(CO)3+ complexes. Six rhenium(I) complexes with general formula fac-[Re(CO)3(N,N')X]+ were prepared, where X = 2-mercapto-1-methylimidazole (methimazole; MMI), and 1-methylimidazole-2-selone (MSeI); N,N' = 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen) and 2,9-dimethyl-1,10-phenanthroline (dmphen). Their triflate salts were characterized using single-crystal X-ray diffraction, 1H, 13C and 2D NMR, UV-vis and vibrational spectroscopy. Their cytotoxic properties were tested, showing significant cytotoxicity (IC50 = 8.0-55 µM) towards the human breast cancer cell line MDA-MB-231. The half-inhibitory concentration (IC50) for fac-[Re(CO)3(dmphen)(MMI)]+, the most toxic complex in this series (8.0 ± 0.2 µM), was comparable to that of the corresponding aqua complex fac-[Re(CO)3(dmphen)(H2O)]+ with IC50 = 6.0 ± 0.1 µM. The fac-[Re(CO)3(bpy)(MMI/MSeI)]+ complexes were somewhat less toxic towards the human embryonic kidney cell line HEK-293 T after 48 h of exposure. The stability of the complexes upon irradiation was monitored using UV-vis spectroscopy, with no CO released when exposed to UV-A light (λ = 365 nm).

Orthogonalization of Polyaryl Linkers as a Route to More Porous Phosphonate Metal-Organic Frameworks.

The coordinative pliancy of the phosphonate functional group means that metal-phosphonate materials often self-assemble as well-packed structures with minimal porosity, as efficient inter-ligand packing is enabled. Here, we report a multistep synthesis of a novel aryl-phosphonate linker with an orthogonalized ligand core, 1,3,5-tris(4'-phosphonophenyl)-2,4,6-trimethylbenzene (H6 L2) designed to form more open structures. A series of crystalline metal-phosphonate frameworks (CALF-35 to -39) have been assembled by coordinating to divalent metals (Ba, Sr, Ca, Mg, Zn). H6 L2 is unable to pack efficiently and, as a consequence, yields several distinct microporous structures. The resulting structures are discussed in detail, with a focus on the solid-state packing of the sterically rigidified linker. Combined with larger cations (Sr, and Ba), H6 L2 packs in a parallel-offset manner, yielding isomorphous and microporous metal-organic frameworks (CALF-35 (Sr), and (Ba)). When coordinated to smaller metals (Ca, Mg, Zn), H6 L2 forms four new structures. Two Ca MOFs of different stoichiometry, (CALF-36 and 37) and a Mg MOF CALF-38 show narrow pores and have high selectivities for CO2 over N2 and CH4 . Finally, in CALF-39 (Zn), H6 L2 linkers pack in a herringbone fashion, resulting in a material with 10.9×10.1 Å2 square channels. The stability of all structures was tested, and the most porous structure, CALF-39 (Zn), was found to retain its structure and gas adsorption after immersion in water over pH 3-11.

A scalable metal-organic framework as a durable physisorbent for carbon dioxide capture.

Metal-organic frameworks (MOFs) as solid sorbents for carbon dioxide (CO2) capture face the challenge of merging efficient capture with economical regeneration in a durable, scalable material. Zinc-based Calgary Framework 20 (CALF-20) physisorbs CO2 with high capacity but is also selective over water. Competitive separations on structured CALF-20 show not just preferential CO2 physisorption below 40% relative humidity but also suppression of water sorption by CO2, which was corroborated by computational modeling. CALF-20 has a low enthalpic regeneration penalty and shows durability to steam (>450,000 cycles) and wet acid gases. It can be prepared in one step, formed as composite materials, and its synthesis can be scaled to multikilogram batches.

Stereoselective copper-catalyzed heteroarene C-H functionalization/Michael-type annulation cascade with α-diazocarbonyls.

A stereoselective, copper-catalyzed, arene C(sp2)-H functionalization/Michael-type annulation reaction involving α-diazocarbonyl compounds has been developed. The method features low catalyst loadings, high yields, and excellent regio and stereoselectivity, in the synthesis of various heteroaromatic frameworks by employing indoles as the arene partner.

Copper-Catalyzed Annulation of Indolyl α-Diazocarbonyl Compounds Leads to Structurally Rearranged Carbazoles.

Indolyl α-diazocarbonyl compounds have proven to be effective starting materials for the construction of various 2,3-ring fused indole frameworks. Activation of the diazo functional group under metal catalysis generates a spiro-cyclic indolenine-type intermediate which rearranges to provide two distinct carbazoles upon oxidation. The current study investigates the effects of the catalyst as well as the substituents on the migratory group involved in controlling the selectivity of the rearrangement.

Synthesis of [2.2]Paracyclophane/9-Alkylfluorene Hybrids and the Discovery of a Solvent-assisted Rearrangement.

Work on the synthesis of [2.2]paracyclophane/9-alkylfluorene hybrids led to the discovery of the rearrangement of cyclopentadienone 7 to cyclophane 6. A DFT computational study revealed that this formal 1,3-alkyl shift occurs in two steps, but requires the participation of a solvent molecule (ethanol). The rearrangement could be avoided by generating 7 under mild conditions and using benzynes as dienophiles to afford the targeted cyclophanes 14 and 16, the latter of which exhibits dual fluorescence emission.

Cytotoxicity, cellular localization and photophysical properties of Re(I) tricarbonyl complexes bound to cysteine and its derivatives.

The potential chemotherapeutic properties coupled to photochemical transitions make the family of fac-[Re(CO)3(N,N)X]0/+ (N,N = a bidentate diimine such as 2,2'-bipyridine (bpy); X = halide, H2O, pyridine derivatives, PR3, etc.) complexes of special interest. We have investigated reactions of the aqua complex fac-[Re(CO)3(bpy)(H2O)](CF3SO3) (1) with potential anticancer activity with the amino acid L-cysteine (H2Cys), and its derivative N-acetyl-L-cysteine (H2NAC), as well as the tripeptide glutathione (H3A), under physiological conditions (pH 7.4, 37 °C), to model the interaction of 1 with thiol-containing proteins and enzymes, and the impact of such coordination on its photophysical properties and cytotoxicity. We report the syntheses and characterization of fac-[Re(CO)3(bpy)(HCys)]·0.5H2O (2), Na(fac-[Re(CO)3(bpy)(NAC)]) (3), and Na(fac-[Re(CO)3(bpy)(HA)])·H2O (4) using extended X-ray absorption spectroscopy, IR and NMR spectroscopy, electrospray ionization spectrometry, as well as the crystal structure of {fac-[Re(CO)3(bpy)(HCys)]}4·9H2O (2 + 1.75 H2O). The emission spectrum of 1 displays a variance in Stokes shift upon coordination of L-cysteine and N-acetyl-L-cysteine. Laser excitation at λ = 355 nm of methanol solutions of 1-3 was followed by measuring their ability to produce singlet oxygen (1O2) using direct detection methods. The cytotoxicity of 1 and its cysteine-bound complex 2 was assessed using the MDA-MB-231 breast cancer cell line, showing that the replacement of the aqua ligand on 1 with L-cysteine significantly reduced the cytotoxicity of the Re(I) tricarbonyl complex. Probing the cellular localization of 1 and 2 using X-ray fluorescence microscopy revealed an accumulation of 1 in the nuclear and/or perinuclear region, whereas the accumulation of 2 was considerably reduced, potentially explaining its reduced cytotoxicity. Replacing the aqua ligand with cysteine in the antitumor active fac-[Re(CO)3(bpy)(H2O)](CF3SO3) complex significantly reduced its cellular accumulation and cytotoxicity against the MDA-MB-213 breast cancer cell line, shifted its maximum emission to considerably higher energies, and decreased its fluorescence quantum yield.

Activation of ammonia and hydrazine by electron rich Fe(ii) complexes supported by a dianionic pentadentate ligand platform through a common terminal Fe(iii) amido intermediate.

We report the use of electron rich iron complexes supported by a dianionic diborate pentadentate ligand system, B2Pz4Py, for the coordination and activation of ammonia (NH3) and hydrazine (NH2NH2). For ammonia, coordination to neutral (B2Pz4Py)Fe(ii) or cationic [(B2Pz4Py)Fe(iii)]+ platforms leads to well characterized ammine complexes from which hydrogen atoms or protons can be removed to generate, fleetingly, a proposed (B2Pz4Py)Fe(iii)-NH2 complex (3Ar-NH2). DFT computations suggest a high degree of spin density on the amido ligand, giving it significant aminyl radical character. It rapidly traps the H atom abstracting agent 2,4,6-tri-tert-butylphenoxy radical (ArO˙) to form a C-N bond in a fully characterized product (2Ar), or scavenges hydrogen atoms to return to the ammonia complex (B2Pz4Py)Fe(ii)-NH3 (1Ar-NH3). Interestingly, when (B2Pz4Py)Fe(ii) is reacted with NH2NH2, a hydrazine bridged dimer, (B2Pz4Py)Fe(ii)-NH2NH2-Fe(ii)(B2Pz4Py) ((1Ar)2-NH2NH2), is observed at -78 °C and converts to a fully characterized bridging diazene complex, 4Ar, along with ammonia adduct 1Ar-NH3 as it is allowed to warm to room temperature. Experimental and computational evidence is presented to suggest that (B2Pz4Py)Fe(ii) induces reductive cleavage of the N-N bond in hydrazine to produce the Fe(iii)-NH2 complex 3Ar-NH2, which abstracts H˙ atoms from (1Ar)2-NH2NH2 to generate the observed products. All of these transformations are relevant to proposed steps in the ammonia oxidation reaction, an important process for the use of nitrogen-based fuels enabled by abundant first row transition metals.

Tandem deoxygenative hydrosilation of carbon dioxide with a cationic scandium hydridoborate and B(C6F5)3.

A scandium hydridoborate complex supported by the dianionic pentadentate ligand B2Pz4Py is prepared via hydride abstraction from the previously reported scandium hydride complex with tris-pentafluorophenyl borane. Exposure of [(B2Pz4Py)Sc][HB(C6F5)3] to CO2 immediately forms [(B2Pz4Py)Sc][HCOOB(C6F5)3] at room temperature. The formatoborate complex can also be synthesized directly from the starting material (B2Pz4Py)ScCl with Et3SiH and B(C6F5)3 while in the presence of an atmosphere of CO2 in 81% yield. This compound was evaluated as the transition metal component of a tandem deoxgenative CO2 hydrosilation catalyst. At 5% loadings, complete consumption of Et3SiH was observed along with CO2 reduction products, but conversion to an inactive scandium complex identified as (B2Pz4Py)ScOSiEt3 was observed.

Supramolecular chirality of coordination polymers of Ag+ with a chiral thiol ligand that bears a ß-turn structure.

We report coordination polymers forming from Ag+ and a chiral thiol ligand that bears a ß-turn structure, exhibiting supramolecular chirality showing both the majority rules effect (MRE) and the racemate rules effect (RRE).

Three Sequential Hydrolysis Products of the Ubiquitous Cu24 Isophthalate Metal-Organic Polyhedra.

Metal-organic polyhedra (MOPs) are increasingly studied as host-guest capsules, linked into networks, or incorporated into composite materials. As such, understanding the decomposition of MOP structures is of fundamental importance. The degradation of the ubiquitous copper(II) MOP Cu24[5-(hydroxy)isophthalate]24 (1) is studied in liquid water. At different intervals of water exposure, powder X-ray diffraction (PXRD) is performed and stepwise conversion of the MOP into three different coordination polymers is observed. First, the formation of a 2D coordination polymer, 2, is observed, which upon further exposure gives a 1D coordination polymer, 3, and finally a trinuclear copper(II) complex, 4. Compound 2 is characterized by PXRD owing to its transient nature, while 3 and 4 are characterized crystallographically. The final structure, 4, contains copper(II) trimers, and so its magnetic behavior is also investigated.

Three Co(II) Metal-Organic Frameworks with Diverse Architectures for Selective Gas Sorption and Magnetic Studies.

Three Co(II) metal-organic frameworks, namely, {[Co2(L)2(OBA)2(H2O)4]· xG} n (1), {[Co(L)0.5(OBA)]· xG} n (2), and {[Co2(L)2(OBA)2(H2O)]·DMA· xG} n (3) [where L = 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene, H2OBA = 4,4'-oxybisbenzoic acid, DMF = dimethylformamide, DMA = dimethylacetamide, and G denotes disordered guest molecules], have been synthesized under diverse reaction conditions through self-assembly of a bent dicarboxylate and a linear spacer with a Co(II) ion. While 1 is crystallized at room temperature in DMF to form a 2D layer structure, 2 is formed by the assembly of similar components under solvothermal conditions with a 3D network structure. On the other hand, changing the solvent to DMA, 3 could be crystallized at room temperature with a 3D architecture. Out of the three, activated sample 2 was found to be permanently microporous in nature, with a BET surface area of 385 m2/g, and exhibited moderately high uptake capacity for C2H2 and CO2 while taking up much less CH4 and N2 at ambient conditions. As a result, high ideal adsorbed solution theory (IAST) separation selectivities are obtained for CO2/N2 (15:85), CO2/CH4 (50:50), and C2H2/CH4 (50:50) gas mixtures, making 2 a potential candidate for those important gas separations at ambient conditions. Moreover, the magnetic properties of 1-3 were studied. 1 and 2 show antiferromagnetic interaction between the Co(II) centers, whereas 3 displays ferromagnetic behavior arising from a counter-complementary effect between two types of links among Co(II) centers in 3.

Synthesis and Structures of Stable PtII and PtIV Alkylidenes: Evidence for π-Bonding and Relativistic Stabilization.

Isolable cationic PtII and PtIV alkylidenes, proposed intermediates in catalytic organic transformations, are reported. The bonding in these species was probed by experimental, structural, spectroscopic, electrochemical and computational methods, providing direct evidence for π-bonding, the often-theorized relativistic stabilization of these species, and the influence of oxidation state.

Design Strategy for the Controlled Generation of Cationic Frameworks and Ensuing Anion-Exchange Capabilities.

Cationic frameworks are an emerging class of exceptional solid adsorbents capable of encapsulating highly toxic and persistent anionic pollutants. The controlled generation of cationic frameworks, however, lags behind the abundant design strategies devised to control the structures and topologies of neutral frameworks. In this regard, we report a rational approach that allows the conversion of the synthetic approach toward constructing a neutral framework into one allowing for the synthesis of a cationic one without incurring any changes to the overall topology or the selected metal ion. We demonstrate that the replacement of a functional group on an organic linker that promotes a similar coordination mode, but bearing one less negative charge, can yield the systematic generation of cationic frameworks. Moreover, we confirm the cationic nature of the metal-organic frameworks through preliminary anion-exchange experiments and propose a method to retain permanent porosity in cationic frameworks through the use of strongly binding anions. Altogether, these results show great promise for the construction of tunable nanoporous frameworks capable of carrying out anion-exchange processes.

Mechanical Properties of a Metal-Organic Framework formed by Covalent Cross-Linking of Metal-Organic Polyhedra.

Overcoming the brittleness of metal-organic frameworks (MOFs) is a challenge for industrial applications. To increase the mechanical strength, MOFs have been blended with polymers to form composites. However, this also brings challenges, such as integration and integrity of MOF in the composite, which can hamper the selectivity of gas separations. In this report, an "all MOF" material with mechanical flexibility has been prepared by covalent cross-linking of metal-organic polyhedra (MOPs). The ubiquitous Cu24 isophthalate MOP has been decorated with a long alkyl chain having terminal alkene functionalities so that MOPs can be cross-linked via olefin metathesis using Grubbs second generation catalyst. Different degrees of cross-linked MOP materials have been obtained by varying the amount of catalyst in the reaction. Rheology of these structures with varying number of cross-links was performed to assess the cross-link density and its homogeneity throughout the sample. The mechanical properties were further investigated by the nanoindentation method, which showed increasing hardness with higher cross-link density. Thus, this strategy of cross-linking MOPs with covalent flexible units allows us to create MOFs of increasing mechanical strength while retaining the MOP cavities.

Scandium alkyl and hydride complexes supported by a pentadentate diborate ligand: reactions with CO2 and N2O.

Alkyl and hydrido scandium complexes of the dianionic pentadentate ligand B2Pz4Py are reported. The key starting material (B2Pz4Py)ScCl is readily prepared and alkylated with organolithium reagents RLi (R = CH3, CH2SiMe3, CH2SiMe2Ph, CH2CH2CH3 and CH2CHMe2) to form alkyl derivatives in 61-93% yields. These compounds are very thermally stable and do not undergo sigma bond metathesis reactions with dihydrogen. The hydrido complex was prepared from (B2Pz4Py)ScCl and NaHBEt3 in 80% yield and was found to be more stable by 28 kcal mol-1 as a dimer, rather than a monomeric hydrido complex. However, the monomer is accessible through dissociation of the dimer at 80 °C. All of the compounds (B2Pz4Py)ScR react with water to form the bridging oxo dimer (B2Pz4Py)ScOSc(B2Pz4Py). The reactivity of the hydrido and methyl complexes towards carbon dioxide was explored; heating to 80 °C results in the formation of κ2 formato and acetate complexes, respectively. The mechanisms were studied via density functional theory and distinct transition states for insertion of CO2 into the Sc-R (R = H, CH3) were found, with the insertion into Sc-CH3 being more enthalpically difficult (by 18 kcal mol-1) than insertion into Sc-H. The slow rate of reaction between [(B2Pz4Py)ScH]2 and CO2 is attributed to the barrier associated with dimer dissociation. In both insertion reactions, the kinetic products are κ1 formato or acetate complexes that are only slightly less stable than the observed κ2 derivatives. The κ1 compounds can therefore be trapped by treating the κ2 isomers with tris-pentafluorophenyl borane.

Single Crystal Proton Conduction Study of a Metal Organic Framework of Modest Water Stability.

A sulfonated indium (In) metal organic framework (MOF) is reported with an anionic layered structure incorporating hydrogen-bonded dimethylammonium cations and water molecules. The MOF becomes amorphous in >60% relative humidity; however, impedance analysis of pelletized powders revealed a proton conduction value of over 10-3 S cm-1 at 25 °C and 40% RH, a very high proton conduction value for low humidity and moderate temperature. Given the modest humidity stability of the MOF, triaxial impedance analyses on a single crystal was performed and confirmed bulk proton conductivity over 10-3 S cm-1 along two axes corroborating the data from the pellet.