Bioshell calcium oxide (BiSCaO) for cleansing and healing Pseudomonas aeruginosa-infected wounds in hairless rats.

BACKGROUND: Scallop shell powder is called bioshell calcium oxide (BiSCaO), which is known to possess deodorizing properties and broad antimicrobial activity against various pathogenic microbes, including viruses, bacteria, spores, and fungi. OBJECTIVE: This study aims to investigate the applications of BiSCaO suspension cleansing in clinical situations, for instance for the prevention and treatment of infections in chronic wounds in healing-impaired patients, without delaying wound healing. METHODS: The bactericidal activities of 1000 ppm BiSCaO suspension; 500 ppm hypochlorous acid; 1000 ppm povidone iodine; and saline were compared to evaluate in vivo disinfection and healing of Pseudomonas aeruginosa-infected wounds in hairless rats. RESULTS: Cleansing of the infected wounds with BiSCaO suspension daily for 3 days significantly enhanced wound healing and reduced the in vivo bacterial counts, in comparison to hypochlorous acid, povidone iodine, and saline. Furthermore, histological examinations showed significantly advanced granulation tissue and capillary formation in the wounds cleansed with BiSCaO suspension than in those cleansed with the other solutions. CONCLUSIONS: This study suggested that the possibility of using BiSCaO suspension as a disinfectant for infected wounds and limiting disinfection to 3 days may be sufficient to avoid the negative effects on wound repair.

A novel approach for fast and simple determination pyrrolizidine alkaloids in herbs by ultrasound-assisted dispersive solid phase extraction method coupled to liquid chromatography-tandem mass spectrometry.

Pyrrolizidine alkaloids (PAs) are secondary plant metabolites witch can contaminate food, especially herbs. Due to the fact that alkaloids have a strong adverse effect on human health, it is necessary to use sensitive and selective detection methods. In present study a modified method based on LC-MS/MS was developed and validated for the simultaneous determination of thirty pyrrolizidine alkaloids and their corresponding N-oxides (PANOs) in herbs samples. Sample extraction was based on ultrasound-assisted dispersive solid phase extraction and clean-up using graphene. Method validation showed that the proposed method hold good recoveries (61-128 %) for PAs/PANOs with RSD <15 %. Limits of quantification has been set at 1 µg kg-1 level for all targeted alkaloids. The optimized method yielded a small matrix effect (-20-20 %) for most PAs/PANOs. The uncertainty associated with the analytical method was not higher than 38 %. The method is operationally simple, time-saving, and can be applied to the analysis of real herb samples.

Safranin O-functionalized cuboid mesoporous silica material for fluorescent sensing and adsorption of permanganate.

Incorporation of dual functions, i.e., sensing and adsorption, into one single organic-inorganic hybrid material for the detection and removal of toxic permanganate (MnO4-) ions is of great importance, representing a challenging and new task in the design and application of new functional materials. However, most of the reported materials display only one function as either sensing probes or adsorbents. In this work, a fluorescent cuboid mesoporous silica-based hybrid material (SiO2@SFNO) is first prepared by the covalent coupling of a new safranin O-based fluorophore (2,8-dimethyl-5-phenyl-3,7-bis(3-(3-(triethoxysilyl)propyl)ureido)phenazin-5-ium chloride) (SFNO) and newly-made cuboid mesoporous silica, which showed selective dual-functional activities towards MnO4- and green emission at 575 nm with a long-range excitation wavelength that is suitable for bio-imaging application. The design of this SiO2@SFNO material is based on the position of -NHCONH- groups, which are mainly responsible for the strong and selective coordination with MnO4-. SiO2@SFNO is responsive to MnO4- at parts per billion (67 ppb) level; it also displays high adsorption ability (292 mg g-1) to MnO4- in aqueous solutions. The fluorescence responses of MnO4-in vivo (limnodrilus claparedianus and zebrafish) demonstrate the possibility of further application in biology. Interestingly, this SiO2@SFNO material is also capable of monitoring trace amounts of Hg2+ and Cu2+ in living organisms, holding great potential in bio-related applications.

Pseudolycorine N-oxide, a new N-oxide from Narcissus tazetta.

A new N-oxide, Pseudolycorine N-oxide (1) was characterised along with eleven known alkaloids homolycorine (2), O-methylmaritidine (3), 8-O-demethylhomolycorine (4), homolycorine N-oxide (5), lycorine (6), narciclasine (7), pseudolycorine (8), ungeremine (9), 8-O-demethylmaritidine (10), zefbetaine (11) and lycorine N-oxide (12), from Narcissus tazetta. Their structures were established on the basis of spectroscopic data analysis. The extract, fractions and isolated compounds were screened for in vitro cytotoxicity against two human cancer cell lines, human cervical cancer (SiHa) and human epidermoid carcinoma (KB) cells. The study demonstrated the cytotoxic potential of extract and its chloroform and n-butanol fractions. Further, the results revealed the bioactive potential of narciclasine, pseudolycorine and homolycorine alkaloids. However, new N-oxide (1) was not active against these cell lines.

A new erythrinan N-oxide alkaloid from Erythrina stricta.

This phytochemical study of stems and leaves of Erythrina stricta led to the isolation of twenty-three alkaloids, one of them previously unreported, 11ß-hydroxyerythratidine N-oxide. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic analyses including HSQC, HMBC, 1H-1H COSY, NOESY, as well as HRESIMS data in addition to comparison with reports in the literature.

[Influence of Hydraulic Retention Time on the Treatment of Polluted River Water by an Activated Carbon Rotating Biological Contactor].

The study combined activated carbon with a rotating biological contactor. The activated carbon adsorption experiments were conducted and the biofilm was formed by using the river water directly. The effects of different hydraulic retention times on the removal of NH4+-N, TP, and permanganate index and on the biofilm properties were investigated at the optimum rotational speed of the disc. Experimental results are as follows. The Freundlich isotherm showed that activated carbon had better adsorption properties for NH4+-N, TP, and permanganate index in water.When the disk speed was 3 r·min-1, the removal efficiency was the best, and the removal rates of NH4+-N, TP and permanganate index were the best at 86.05%, 81.28%, and 77.09%, respectively. In addition, there was a significant linear correlation between the hydraulic retention time and the removal of NH4+-N and TP (R2>0.9), respectively. The removal rates of NH4+-N and TP at different hydraulic retention times were significantly different (P<0.05), but the permanganate index was not (P>0.05).Hydraulic retention time had effects on the biofilm activity, protein and polysaccharide contents,and the three-dimensional fluorescence peaks of S-EPS, LB-EPS, and TB-EPS of the biofilm.

Copper Binding Sites in the Manganese-Oxidizing Mnx Protein Complex Investigated by Electron Paramagnetic Resonance Spectroscopy.

Manganese-oxide minerals (MnOx) are widely distributed over the Earth's surface, and their geochemical cycling is globally important. A multicopper oxidase (MCO) MnxG protein from marine Bacillus bacteria plays an essential role in producing MnOx minerals by oxidizing Mn2+(aq) at rates that are 3 to 5 orders of magnitude faster than abiotic rates. The MnxG protein is isolated as part of a multiprotein complex denoted as "Mnx" that includes accessory protein subunits MnxE and MnxF, with an estimated stoichiometry of MnxE3F3G and corresponding molecular weight of ≈211 kDa. Herein, we report successful expression and isolation of the MCO MnxG protein without the E3F3 hexamer. This isolated MnxG shows activity for Mn2+(aq) oxidation to form manganese oxides. The complement of paramagnetic Cu(II) ions in the Mnx protein complex was examined by electron paramagnetic resonance (EPR) spectroscopy. Two distinct classes of type 2 Cu sites were detected. One class of Cu(II) site (denoted as T2Cu-A), located in the MnxG subunit, is identified by the magnetic parameters g∥ = 2.320 and A∥ = 510 MHz. The other class of Cu(II) sites (denoted as T2Cu-B) is characterized by g∥ = 2.210 and A∥ = 615 MHz and resides in the putative hexameric MnxE3F3 subunit. These different magnetic properties correlate with the differences in the reduction potentials of the respective Cu(II) centers. These studies provide new insights into the molecular mechanism of manganese biomineralization.

MnO2 Submicroparticles from Chinese Brush and Their Application in Treatment of Methylene Blue Contaminated Wastewater.

Eggshell membrane (ESM) is selected as biotemplate to prepare MnO2 submicroparticles (SMPs) using Chinese Brush with sodium hydroxide solution. The size with average 710 nm of the obtained materials is in good consistency with the microsructured biotemplate. An efficient and convenient absorbent for methylene blue (MB) is developed. The removal efficiency could reach up to 93% in 35 min under room temperature without pH adjusting owing to the excellent adsorption from ESM itself and hydroxyl group formed on the surface of MnO2 crystal in the aqueous solution. Materials on the membrane can be separated from the wastewater simply to avoid the secondary pollution caused by the leak of material. This interesting approach to MnO2 SMPs and facile operation for MB adsorption could open a new path to the submicro-materials based wastewater treatment.

[Purification of Slightly Salt-alkaline Water Bodies by Microorganism Enhanced Combined Floating Bed].

In order to study the purifying effect of combined floating bed constucted by salinity plant Suaeda salsa and microorganisms on the slightly salt-alkaline water, blank floating bed A, S.salsa floating bed B, microbes floating bed C and S.salsa + microorganisms combined floating bed D were established, and slightly salt-alkaline eutrophic water body (pH 8.5-9.0, salinity 5‰-7‰) was purified under continuous flow conditions in the laboratory. Results showed that the removal rates of total nitrogen, total phosphorus, permanganate index by S.salsa floating bed were 32.5%, 14.3% and 28.2%, respectively. And the removal rates of total nitrogen, total phosphorus and permanganate index by S.salsa + microorganisms combined floating bed D which installed artificial medium with microorganisms reached 70.5%, 34.7% and 70.8%, respectively, of which the removal rates of total nitrogen, total phosphorus and permanganate index by microbial units were 37.7%, 21.6% and 44.5%, respectively. Synergies removal rates of nitrate nitrogen and total nitrogen by S.salsa + microorganisms combined floating bed were 12.2% and 0.3%, but there was no synergy in the process of removing ammonia nitrogen, total phosphorus and permanganate index, which indicated that the synergies of S.salsa and microorganisms in the combined floating bed were suppressed in slightly salt-alkaline environment. The high-throughput sequencing technique was adopted to analyze the microbial community in the floating bed C and D, which indicated that the abundance and diversity of microbial community in the combined floating bed were higher, and this was consistent with the result of the higher removal rate of the flotation bed D. Principal component analysis showed that the microbial degradation was a major factor in reducing the concentration of pollutants. This study provided a guide for the using of floating bed in purifying slightly salt-alkaline eutrophic water bodies in coastal area.

A Water-Stable Cationic Metal-Organic Framework as a Dual Adsorbent of Oxoanion Pollutants.

A three-dimensional water-stable cationic metal-organic framework (MOF) pillared by a neutral ligand and with Ni(II)  metal nodes has been synthesized employing a rational design approach. Owing to the ordered arrangement of the uncoordinated tetrahedral sulfate (SO4 (2-) ) ions in the channels, the compound has been employed for aqueous-phase ion-exchange applications. The compound exhibits rapid and colorimetric aqueous-phase capture of environmentally toxic oxoanions (with similar geometries) in a selective manner. This system is the first example of a MOF-based system which absorbs both dichromate (Cr2 O7 (2-) ) and permanganate (MnO4 (-) ) ions, with the latter acting as a model for the radioactive contaminant pertechnetate (TcO4 (-) ).

Medicinal plants of Papua New Guinea's Miu speaking population and a focus on their use of plant-slaked lime mixtures.

ETHNOPHARMACOLOGICAL RELEVANCE: Here we present the results of an ethnobotanical survey of the medicinal plants used by the Miu, a virtually unresearched ethnolinguistic group who live in the mountainous interior of Papua New Guinea's West New Britain Province. We compare the findings for those previously reported for the neighbouring inland Kaulong speaking population. Three species, Trema orientalis, Spondias dulcis and Ficus botryocarpa are used in combination with locally prepared slaked lime to produce intensely coloured mixtures which are applied to dermatological infections. Their effects on dermal fibroblast viability with and without slaked lime are examined. The sap of F. botryocarpa which is used to treat tropical ulcers was examined further with assays relevant to wound healing. MATERIALS AND METHODS: Focus groups and semi-structured interviews were used to acquire information on the uses of plants, vouchers of which were collected and identified by comparison with authentic herbarium specimens. LC-MS and NMR were used to identify chemical components. Cell viability assays were used to examine the effects of added slaked lime on dermal fibroblasts. For the sap of F. botryocarpa, fibroblast stimulation assays and antibacterial growth inhibition with Bacillus subtilis were carried out. RESULTS: The survey identified 33 plants and one fungal species, and clear differences with the inland Kaulong group despite their close proximity. Added slaked lime does not greatly increase the cytotoxicity of plant material towards dermal fibroblasts. The sap of F. botryocarpa contains the alkaloid ficuseptine as a single major component and displays antibacterial activity. CONCLUSIONS: The results demonstrate the potential for variation in medicinal plant use amongst Papua New Guinea's numerous language groups. The addition of slaked lime to plant material does not appear to present a concern for wound healing in the amounts used. The sap of F. botryocarpa displays antibacterial activity at concentrations that would occur at the wound surface and could be used as a highly accessible alternative to conventional antiseptics for remote communities in Papua New Guinea.

Development of preparative and analytical methods of the hop bitter acid oxide fraction and chemical properties of its components.

The bitter acids in hops (Humulus lupulus L.) and beer, such as α-, ß-, and iso-α-acids, are known to affect beer quality and display various physiological effects. However, these compounds readily oxidize, and the effect of the oxides on the properties of beer or their potential health benefits are not well understood. In this study, we developed a simple preparative method for the bitter acid oxide fraction derived from hops and designated the constituents as matured hop bitter acids (MHBA). HPLC-PDA-ESI/HRMS and MS(2) revealed that MHBA are primarily composed of α-acid-derived oxides, which possess a common ß-tricarbonyl moiety in their structures similar to α-, ß-, and iso-α-acids. We also developed a quantitative analytical method of whole MHBA by HPLC, which showed high precision and reproducibility. Using our newly developed method, the concentration of whole MHBA in several commercial beers was evaluated. Our results will promote the study of bitter acid oxides.

CO2 , NOx and SOx removal from flue gas via microalgae cultivation: a critical review.

Flue gas refers to the gas emitting from the combustion processes, and it contains CO2 , NOx , SOx and other potentially hazardous compounds. Due to the increasing concerns of CO2 emissions and environmental pollution, the cleaning process of flue gas has attracted much attention. Using microalgae to clean up flue gas via photosynthesis is considered a promising CO2 mitigation process for flue gas. However, the impurities in the flue gas may inhibit microalgal growth, leading to a lower microalgae-based CO2 fixation rate. The inhibition effects of SOx that contribute to the low pH could be alleviated by maintaining a stable pH level, while NOx can be utilized as a nitrogen source to promote microalgae growth when it dissolves and is oxidized in the culture medium. The yielded microalgal biomass from fixing flue gas CO2 and utilizing NOx and SOx as nutrients would become suitable feedstock to produce biofuels and bio-based chemicals. In addition to the removal of SOx , NOx and CO2 , using microalgae to remove heavy metals from flue gas is also quite attractive. In conclusion, the use of microalgae for simultaneous removal of CO2 , SOx and NOx from flue gas is an environmentally benign process and represents an ideal platform for CO2 reutilization.

Simultaneous recovery of Zn and MnO2 from used batteries, as raw materials, by electrolysis.

High purity electrolytic manganese dioxide (EMD) is the main raw material used for manufacturing of zinc and manganese based portable batteries (alkaline with manganese AlMn and zinc carbon Zn-C). Lately, due to the progressive depletion of MnO(2) natural resources, the quantity of artificially electrolytic produced MnO(2) has started to increase to satisfy the demand. This paper describes an electrolytic process for the simultaneous production of the following components:The electrolysis process was conducted in a specialized laboratory facility. The study was particularly focused on the following electrolysis process parameters:

Recovery of manganese oxides from spent alkaline and zinc-carbon batteries. An application as catalysts for VOCs elimination.

Manganese, in the form of oxide, was recovered from spent alkaline and zinc-carbon batteries employing a biohydrometallurgy process, using a pilot plant consisting in: an air-lift bioreactor (containing an acid-reducing medium produced by an Acidithiobacillus thiooxidans bacteria immobilized on elemental sulfur); a leaching reactor (were battery powder is mixed with the acid-reducing medium) and a recovery reactor. Two different manganese oxides were recovered from the leachate liquor: one of them by electrolysis (EMO) and the other by a chemical precipitation with KMnO4 solution (CMO). The non-leached solid residue was also studied (RMO). The solids were compared with a MnOx synthesized in our laboratory. The characterization by XRD, FTIR and XPS reveal the presence of Mn2O3 in the EMO and the CMO samples, together with some Mn(4+) cations. In the solid not extracted by acidic leaching (RMO) the main phase detected was Mn3O4. The catalytic performance of the oxides was studied in the complete oxidation of ethanol and heptane. Complete conversion of ethanol occurs at 200°C, while heptane requires more than 400°C. The CMO has the highest oxide selectivity to CO2. The results show that manganese oxides obtained using spent alkaline and zinc-carbon batteries as raw materials, have an interesting performance as catalysts for elimination of VOCs.

Application of DGT to high pH environments: uptake efficiency of radionuclides of different oxidation states onto Chelex binding gel.

The DGT Chelex binding phase has not been tested for binding efficiency over the extreme high pH range (i.e., 10 to 13). Here, we examined the uptake efficiency of the gel-encapsulated Chelex cation exchange resin binding phase when in direct contact with solutions of radionuclides of different oxidation states over the circumneutral to high pH range (∼7 to 13). Results show that the Chelex binding gel is suitable for Eu(3+) for circumneutral pH, for UO2(2+) up to at least pH 10.7 and for NpO2(+) up to at least pH 11.7. Application may be appropriate at higher pH values but testing of complete solution deployment units will be required. This work provides the framework to use DGT as a tool for the study of high pH radionuclide systems.

Kinetics of lead(IV) oxide (PbO2) reductive dissolution: role of lead(II) adsorption and surface speciation.

Lead(IV) oxide (PbO(2)) is a corrosion product on lead pipes used for drinking water distribution, and its dissolution can control lead release to drinking water. This study evaluated the adsorption of Pb(II) to PbO(2) and its impact on the dissolution rate of PbO(2). The dissolution rate of PbO(2) was determined as a function of pH in the absence and presence of free chlorine using continuously-stirred tank reactors. Pb(II) adsorption was examined as a function of pH and initial Pb(II) concentrations. The dissolution rate of PbO(2) increased with decreasing pH. The presence of free chlorine inhibited PbO(2) dissolution. The dissolution of PbO(2) involves a coupled reduction-detachment process, and a model was developed that accounts for the adsorption of Pb(II) from the reduction. The extent of Pb(II) adsorption to PbO(2) increased with increasing pH and Pb(II) concentrations until reaching a plateau. Adsorption was interpreted with a surface complexation model using the diffuse double-layer model and a single surface complex. The dissolution rate of PbO(2) was directly related to the distribution of the PbO(2) surface species predicted by the surface complexation model. The dissolution rate was predominantly controlled by >Pb(IV)OH(2)(+) for acidic conditions and by>Pb(IV)OH and>Pb(IV)O(-) at neutral to basic conditions.

Synthesis of magnetic ß-cyclodextrin-chitosan/graphene oxide as nanoadsorbent and its application in dye adsorption and removal.

Magnetic ß-cyclodextrin-chitosan/graphene oxide materials (MCCG) were fabricated through a facile chemical route and their application as excellent adsorbents for dye removal were also demonstrated. The characteristics results of FTIR, SEM, TEM and XRD showed that MCCG was successfully prepared. The results showed that, benefiting from the surface property of graphene oxide, hydrophobicity of ß-cyclodextrin, the abundant amino and hydroxyl functional groups of chitosan, and from the magnetic property of Fe(3)O(4), the adsorbent possesses quite a good and versatile adsorption capacity to the dye under investigation, and can be easily and rapidly extracted from water by magnetic attraction. Most importantly, the adsorbent can be easily and efficiently regenerated for reuse with hardly any compromise of the adsorption capacity. The adsorption kinetics, isotherms and thermodynamics were investigated to indicate that the kinetics and equilibrium adsorptions were well-described by pseudo-second-order kinetic and Langmuir isotherm model, respectively. The thermodynamic parameters suggested that the adsorption process was spontaneous and endothermic in nature. The inherent advantages of the nano-structured adsorbent, such as adsorption capacity, easy, handy operation, rapid extraction, and regeneration, may pave a new, efficient and sustainable way towards highly-efficient dye pollutant removal in water and wastewater treatment.

Nanostructured metal oxide gas sensors, a survey of applications carried out at SENSOR lab, Brescia (Italy) in the security and food quality fields.

In this work we report on metal oxide (MOX) based gas sensors, presenting the work done at the SENSOR laboratory of the CNR-IDASC and University of Brescia, Italy since the 80s up to the latest results achieved in recent times. In particular we report the strategies followed at SENSOR during these 30 years to increase the performance of MOX sensors through the development of different preparation techniques, from Rheotaxial Growth Thermal Oxidation (RGTO) to nanowire technology to address sensitivity and stability, and the development of electronic nose systems and pattern recognition techniques to address selectivity. We will show the obtained achievement in the context of selected applications such as safety and security and food quality control.

Preparation of lead oxide nanoparticles from cathode-ray tube funnel glass by self-propagating method.

This paper presents a novel process of extracting lead oxide nanoparticles from cathode-ray tube (CRT) funnel glass using self-propagating high-temperature synthesis (SHS) method. The impacts of added amount of funnel glass on the extraction ratio of lead, the lead extraction velocity and the micromorphology, as well as particle size of extracted nanoparticles were investigated. We found that self-propagating reaction in the presence of Mg and Fe(2)O(3) could separate lead preferentially and superfine lead oxide nanoparticles were obtained from a collecting chamber. The separation ratio was related closely to the amount of funnel glass added in the original mixture. At funnel glass addition of no more than 40wt.%, over 90wt.% of lead was recovered from funnel glass. High extraction yield reveals that the network structure of funnel glass was fractured due to the dramatic energy generated during the SHS melting process. The PbO nanoparticles collected show good dispersion and morphology with a mean grain size of 40-50nm.