Novel use of Kombucha consortium to reduce Escherichia coli in dairy shed effluent.

BACKGROUND: Faecal contamination from dairy farm effluent is a major risk to water quality in New Zealand. In this experiment we have tested the efficacy of Kombucha SCOBY (symbiotic culture of bacteria and yeast), to reduce the concentration of Escherichia coli in dairy shed effluent (DSE). RESULTS: Kombucha SCOBY was highly effective in lowering the number of E. coli colony forming units (CFUs) to levels that were undetectable. The decrease in CFUs occurred rapidly within 48 h of Kombucha SCOBY being inoculated to the effluent matrix and was accompanied by a corresponding decline in pH. CONCLUSION: We conclude that Kombucha SCOBY was effective in reducing the abundance of E. coli in DSE due to its effect on solution pH. Further work is required to assess the practicality of treating DSE with Kombucha SCOBY within a farm environment where effluent management and climatic complexities are important. © 2021 Society of Chemical Industry.

Combination and processing keratin with lignin as biocomposite materials for additive manufacturing technology.

Additive manufacturing using Nature's resources is a desirable goal. In this work we examine how the inherent macromolecular properties of keratin and lignin can be utilised and developed using green chemistry principles to form 4D functional materials. A new methodology utilising protein complexation by lignin was applied to form copolymers and reinforce keratin cross-linking networks on aqueous and solid state processing. Solubility, chemical and processing characteristics found a favoured 4:1 ratio of keratin to lignin was most desired for effective further processing as 3D printed paste forms. Thermally processing keratin-lignin with plasticisers and processing aids demonstrated extruded FDM filaments could be formed at temperatures >130°C, but degradation of keratin-lignin materials was observed. Employing paste printing strategies, keratin-lignin hydrogels could successfully print 3D skirt outlines. This was achieved with aqueous hydrogels prepared at 30-40% solids content with and without plasticizers over a defined processing timeframe. Mechanical response to moisture stimuli was successfully demonstrated for the 4:1 keratin-lignin printed material on water soaking, realising the ability of these keratin-lignin biocomposite materials to introduce a 4th dimensional response after 3D printing. STATEMENT OF SIGNIFICANCE: In this paper we describe new perspectives for how biopolymers can be used and processed to develop (co)polymers as 3D & 4D printed responsive materials without the need for synthetic chemical modifications. We utilise a novel methodology employing bioconjugation to synthesise and develop co-polymer materials from keratin and lignin and demonstrate this can be achieved in both water and solid state. We manipulate the inherent chemical attributes of both biopolymers to develop these new functional materials under green chemistry processing conditions. This is a practical example how the chemical coupling of two biopolymers at molecular-scale can be leveraged to give co-polymer materials which retain their inherent macromolecular properties to behave as functional, 4D responsive biomaterials.

New keratin isolates: actives for natural hair protection.

Hair is primarily composed of keratin proteins and it is well established that peptides and proteins bestow desirable effects on the hair, for example improving moisturization and softness. In the present work we describe how keratin actives with unique properties convey a range of beneficial properties to a variety of hair types. It has been observed that these functional keratins protect hair from damage associated with chemical treatments such as perming and relaxation, help to restore the mechanical strength of damaged fibers and decrease fading of colored hair.

Discovery and Characterization of a Potent Interleukin-6 Binding Peptide with Neutralizing Activity In Vivo.

Interleukin-6 (IL-6) is an important member of the cytokine superfamily, exerting pleiotropic actions on many physiological processes. Over-production of IL-6 is a hallmark of immune-mediated inflammatory diseases such as Castleman's Disease (CD) and rheumatoid arthritis (RA). Antagonism of the interleukin IL-6/IL-6 receptor (IL-6R)/gp130 signaling complex continues to show promise as a therapeutic target. Monoclonal antibodies (mAbs) directed against components of this complex have been approved as therapeutics for both CD and RA. To potentially provide an additional modality to antagonize IL-6 induced pathophysiology, a peptide-based antagonist approach was undertaken. Using a combination of molecular design, phage-display, and medicinal chemistry, disulfide-rich peptides (DRPs) directed against IL-6 were developed with low nanomolar potency in inhibiting IL-6-induced pSTAT3 in U937 monocytic cells. Targeted PEGylation of IL-6 binding peptides resulted in molecules that retained their potency against IL-6 and had a prolongation of their pharmacokinetic (PK) profiles in rodents and monkeys. One such peptide, PN-2921, contained a 40 kDa polyethylene glycol (PEG) moiety and inhibited IL-6-induced pSTAT3 in U937 cells with sub-nM potency and possessed 23, 36, and 59 h PK half-life values in mice, rats, and cynomolgus monkeys, respectively. Parenteral administration of PN-2921 to mice and cynomolgus monkeys potently inhibited IL-6-induced biomarker responses, with significant reductions in the acute inflammatory phase proteins, serum amyloid A (SAA) and C-reactive protein (CRP). This potent, PEGylated IL-6 binding peptide offers a new approach to antagonize IL-6-induced signaling and associated pathophysiology.

Amplification of a cyclic mixed-metalloporphyrin tetramer from a dynamic combinatorial library through orthogonal metal coordination.

A cyclic porphyrin tetramer, consisting of two bis-phosphine substituted zinc(II) porphyrin units and two Rh(III)TPP units, is selected and amplified virtually quantitatively from a dynamic combinatorial library using 4,4'-bipy as a scaffold and using orthogonal binding modes.

Spectroelectrochemical Studies of Copper(I) Complexes with Binaphthyridine and Biquinoline Ligands. Crystal Structure Determination of Bis(6,7-dihydrodipyrido[2,3-b:3',2'-j][1,10]phenanthroline)copper(I) Tetrafluoroborate.

The electrochemical and spectral properties of some copper(I) polypyridyl complexes based on 6,7-dihydrodibenzo[b,j][1,10]phenanthroline, dmbiq, and 6,7-dihydrodipyrido[2,3-b:3',2'-j][1,10]phenanthroline, dmbinap, are reported. These complexes are [Cu(dmbiq)(2)](+), 1; [Cu(dmbiq)(PPh(3))(2)](+), 2; [Cu(dmbinap)(2)](+), 3; and [Cu(dmbinap)(PPh(3))(2)](+), 4. 3 and 4 may be reduced to form ligand-based radical anion species. The resonance Raman spectra of 3(*)()(-)() and 4(*)()(-)() are almost identical and correspond closely to the spectrum of dmbinap(*)()(-)() and the reported spectra of complexes containing 2,2'-biquinoline radical anion moieties. Reduction processes for 1 and 2 are irreversible. For 1 the electronic spectral changes arising from reduction suggest demetallation of the complex. The structure of [Cu(C(18)H(12)N(4))(2)][BF(4)].CH(2)Cl(2) (3[BF(4)].CH(2)Cl(2)) was determined by single-crystal X-ray diffraction. It crystallized in the monoclinic space group P2(1)/c with cell dimensions a = 14.059(7) Å, b = 15.058(6) Å, c = 16.834(9) Å, beta = 111.56(5) degrees, Z = 4, rho(calcd) = 1.611 g/cm(3), and R(F(o)) = 0.0497.

An ex vivo methodology to assess the lipid peroxidation in stratum corneum.

Environmental risks, particularly UV radiation, provide a challenge to the function of the skin barrier. Protective measures such as the use of antioxidant products represent a possible method of providing protection to the skin. This paper reports the development of a non-invasive ex vivo method using tape strips of the outermost layers of stratum corneum (SC) from human volunteers in order to determine the effectiveness of an antioxidant emulsion topically applied to prevent lipid peroxidation (LPO) in the horny layer after an UV irradiation exposure. Two different formulations were used: formulation (A), containing Vitamin A, E and C, and formulation (B) containing fish extract. Both formulations were topically applied in vivo on volunteer forearms; then, a tape stripping of the SC of each volunteer was carried out. The lipid peroxidation was measured ex vivo after an UV irradiation of the SC samples. The amount of SC stripped to evaluate differences in lipid peroxidation, the UV irradiation intensity to form lipid peroxides and the accuracy of lipid peroxide analysis were optimized in this methodology using formulation (A). After an exposure application of seven days, a group of three strips of the outermost layers of SC of volunteers was irradiated with an intensity of 182.7 J/cm(2) to quantify the LPO inhibition. The percentage of LPO inhibition obtained after topical application of both formulations was in the range of 40-58% demonstrating the effectiveness of the formulations topically applied against lipid peroxidation on human SC. This methodology may be used as a quality control tool to determine ex vivo the percentage of the LPO inhibition on human SC for a variety of antioxidants topically applied.

The effect of reduction on rhenium(I) complexes with binaphthyridine and biquinoline ligands: a spectroscopic and computational study.

A number of rhenium complexes with binaphthyridine and biquinoline ligands have been synthesized and studied. These are [Re(L)(CO)3Cl] where L = 3,3'-dimethylene-2,2'-bi-1,8-naphthyridine (dbn), 2,2'-bi-1,8-naphthyridine (bn), 3,3'-dimethylene-2,2'-biquinoline (dbq), and 3,3'-dimethyl-2,2'-biquinoline (diq). This series represents ligands in which the electronic properties and steric preferences are tuned. These complexes are modeled using density functional theory (DFT). An analysis of the resonance Raman spectra for these complexes, in concert with the vibrational assignments, reveals that the accepting molecular orbital (MO) in the metal-to-ligand charge transfer (MLCT) transition is the LUMO and causes bonding changes at the inter-ring section of the ligand. The electronic absorption spectroelectrochemistry for the reduced complexes of [Re(dbn)(CO)3Cl], [Re(dbq)(CO)3Cl], and [Re(diq)(CO)3Cl] suggest that the singly occupied MO is delocalized over the entire ligand structure despite the nonplanar nature of the diq ligand in [Re(diq)(CO)3Cl]. The IR spectroelectrochemistry for [Re(dbn)(CO)3Cl], [Re(dbq)(CO)3Cl], and [Re(bn)(CO)3Cl] reveal that reduction lowers the CO ligand vibrational frequencies to a similar extent in all three complexes. The substitution of naphthyridine for quinoline has little effect on the nature of the singly occupied MO. These data are supported by DFT calculations on the reduced complexes, which reveal that the ligands are flattened out by reduction: This may explain the similarity in the properties of the reduced complexes.

Complexation of diphenyl(phenylacetenyl)phosphine to rhodium(III) tetraphenyl porphyrins: synthesis and structural, spectroscopic, and thermodynamic studies.

The coordination of diphenyl(phenylacetenyl)phosphine (DPAP, 1) to (X)Rh(III)TPP (X = I (2) or Me (3); TPP = tetraphenyl porphyrin) was studied in solution and in the solid state. The iodide is readily displaced by the phosphine, leading to the bis-phosphine complex [(DPAP)(2)Rh(TPP)](I) (4). The methylide on rhodium in 3 is not displaced, leading selectively to the mono-phosphine complex (DPAP)(Me)Rh(TPP) (5). The first and second association constants, as determined by isothermal titration calorimetry and UV-vis titrations, are in the range 10(4)-10(7) M(-1) (in CH(2)Cl(2)). Using LDI-TOF mass spectrometry, the mono-phosphine complexes can be detected but not the bis-phosphine complexes. The electronic spectrum of 4 is similar to those previously reported with other tertiary phosphine ligands, whereas (DPAP)(I)Rh(TPP) (6) displays a low energy B-band absorption and a high energy Q-band absorption. In contrast to earlier reports, displacement of the methylide on rhodium in 5 could not be observed at any concentration, and the electronic spectra of 4 and 5 are almost identical. Isothermal titration calorimetry experiments showed that all binding events are exothermic, and all are enthalpy driven. The largest values of DeltaG degrees are found for 6. The thermodynamic and UV-vis data reveal that the methylide and the phosphine ligand have an almost identical electronic trans-influence on the sixth ligand.

Toward functionalized conducting polymers: synthesis and characterization of novel beta-(styryl)terthiophenes.

Metal-catalyzed coupling methodologies have been employed in the synthesis of the key building block 3'-formyl-2,2':5',2"-terthiophene. Wittig olefinations with this aldehyde have produced five novel beta-styryl-substituted terthiophene monomers. These materials have been fully characterized by NMR spectroscopy, microanalysis, mass spectrometry, and X-ray crystal structure analysis. The results from the UV/visible spectroscopy and cyclic voltammetric investigations are reported.

Selection and amplification of mixed-metal porphyrin cages from dynamic combinatorial libraries.

Mixed metallo-porphyrin cages were selected and amplified from dynamic combinatorial libraries (DCLs) by using appropriate templates. The cages are composed of two bisphosphine substituted zinc(II) porphyrins as ligand donors and two rhodium(III) or ruthenium(II) porphyrins as ligand acceptors, and are connected through metal-phosphorus coordination. Ru and Rh porphyrins that display a large structural diversity were employed. The templating was achieved by using 4,4'-bpy, 3,3'-dimethyl-4,4'-bipyridine and benzo[lmn]-3,8-phenanthroline, and acts through zinc-nitrogen coordination. The absolute amount of amplification from the DCLs is strongly dependent on the combination of the Ru/Rh porphyrin and the template; cages with sterically demanding porphyrins can only form with smaller templates. In the case of tert-butyl-substituted TPP (TPP=tetraphenylporphyrin), cages are not formed at all. The formation of the cages is usually complete within 24 h at an ambient temperature; in the case of the cage containing Rh(III)OEP (OEP=octaethylporphyrin) and bpy, the pseudo-first-order rate constant of cage formation was determined to be 2.1+/-0.1x10(-4) s(-1) (CDCl(3), 25 degrees C). Alternatively, heating the mixtures to 65 degrees C and cooling to room temperature yields the cages within minutes. The (1)H NMR chemical shifts of several characteristic protons show large differences upon changing the identity of the Ru/Rh porphyrin and the central metal; this is most likely to arise from variations in the geometry of the cages. The X-ray crystal structure of a cage, which contains Rh(III)OEP as a porphyrin acceptor and bpy as template, demonstrates that the cages can adopt severely distorted conformations to accommodate the relatively short templates. An extension to mixed DCLs showed that only limited selectivity is displayed by the various templates. Formation of mixed cages that contain two different rhodium porphyrins prevents effective selection, although the kinetic lability of the systems allows for some amplification. This lability, however, also prevents isolation of the individual cages. Removal of the template leads to re-equilibration, thus the templates act as scaffolds to keep the structures intact.

Construction of multiporphyrin arrays using ruthenium and rhodium coordination to phosphines.

The synthesis of linear multiporphyrin arrays with mono- and bisphosphine-substituted porphyrins as ligand donors and ruthenium(II) or rhodium(III) porphyrins as ligand acceptors is described. With appropriate amounts of the building blocks mixed, linear dimeric and trimeric arrays have been synthesized and analyzed by (1)H NMR and (31)P NMR spectroscopy. The Ru/Rh acceptor porphyrins can be located either at the periphery or in the center of the array. Likewise, the monophosphine porphyrins can be positioned at the periphery, thus allowing a high degree of freedom in the overall composition of the arrays. This way, both donor and acceptor porphyrins can act as chain extenders or terminators. One of the trimeric complexes with two nickel and one ruthenium porphyrin has also been analyzed by X-ray crystallography. Attempts have also been made to synthesize higher order arrays by mixing appropriate amounts of the porphyrins; however, from the NMR data it cannot be concluded if monodisperse five, seven, or nine porphyrin arrays are present or if the solutions are composed of a statistical mixture of smaller and larger arrays.