Removal of nutrients from piggery wastewater using struvite precipitation and pyrogenation technology

In this paper, removal of nutrients from piggery wastewater by struvite crystallization was conducted using a combined technology of low-cost magnesium source in struvite precipitation and recycling of the struvite pyrolysate in the process. In the present research, it was found that high concentrations of K⁺ and Ca²⁺ present in the solution significantly affected the removal of nutrients. When the struvite crystallization formed at the condition of dosing the magnesite pyrolysate at a Mg:N:P molar ratio of 2.5:1:1, and having a reaction time of 6 h, a majority of nutrients in piggery wastewater can be removed. Surface characterization analysis demonstrated that the main components of the pyrolysate of the obtained struvite were amorphous magnesium sodium phosphate (MgNaPO₄) and MgO. When the struvite pyrolysate was recycled in the process at the pH range of 8.0-8.5, the precipitation effect was optimum. When the struvite pyrolysate was recycled repeatedly at pH 8.5 or without any adjustment of pH, the outcome of the removal of the nutrients in both cases was similar. With the increase in the number of recycle times, the performance of struvite precipitation progressively decreased. An economic evaluation showed that the combination of using low-cost material and recycling of struvite was feasible. Recycling struvite for three process cycles could save the chemical costs by 81% compared to the use of pure chemicals.     

Isolation of N,N-dialkylated derivatives of valproylglycinamide from dog plasma by active charcoal adsorption and their quantification by high-performance liquid chromatography

A selective assay for quantification of N,N-dimethylvalproylglycinamide (DM-VGD) and N,N-diethylvalproylglycinamide (DE-VGD) in dog plasma utilizing reversed-phase high-performance liquid chromatography and UV detection has been developed. These compounds are derivatives of the potential anticonvulsant drug, valproylglycinamide, which is currently undergoing clinical trials. The method is based on extraction of dog plasma with activated charcoal, separation of the charcoal pallet and extracting it with methanol, evaporation of the solvent and injecting the reconstituted residue onto the column. The active charcoal adsorption method is reliable and reproducible, and it provides a chromatogram free of interfering endogenous plasma compounds. The assay was validated and provided a limit of quantification of 2.3 mmol/l for DE-VGD and 5.3 mmol/l for DM-VGD. Mean recovery of these compounds from plasma averages 75%. This analytical method is suitable for the quantitative determination of DM-VGD and DE-VGD in plasma and it has been applied to a pharmacokinetic study of these compounds in a dog.     

Recovery after freezing and thawing of cultured human diploid fibroblasts

Fibroblast strains established from donors differing in age, sex, and genetic disease were frozen and thawed under variable conditions and cell survival was determined. The cell density of the monolayer prior to freezing was found to be the most important parameter for optimal cell recovery after freezing to ?196 °C and thawing. We obtained the best results with exponentially growing cells at about half the individual saturation density. Cell recovery was influenced neither by parameters defined by the donor of the skin biopsy, nor by the number of passages during the exponential growth phase, nor by repeated trypsinization and freezing. Application of different linear cooling velocities which were attained by a novel programmable freezing system yielded similar cell survival rates within a wide range from 0.05 to 10 °C/min.     

Isolation and characterization of N6-succinyladenosine from human urine.

From the urines of colon carcinoma patients and normal subjects we have isolated a nucleoside in which an amino group of aspartic acid is attached to the six position of purine ribonucleoside. The structure, N6-succinyladenosine, N-(9-B-D-ribofuranosylpurin-6-yl)aspartic acid was assigned on the basis of spectral data, chemical degradation, and by synthesis. The ultraviolet and mass spectra, chromatographic and electrophoretic mobilities, and the chemical properties of the naturally occurring nucleoside were identical to those of the synthetic N6-succinyladenosine. In contrast to the methylated and hypermodified nucleosides which are products of RNA catabolism, this urinary nucleoside appears to be derived from adenylosuccinic acid, a key intermediate required in the biosynthesis of ubiquitous, natural purine nucleotide adenosine-5'-monophosphate (AMP).     

Use of macroreticular resins for the adsorption of urokinase from human urine

Summary 22 commercial macroreticular resins were screened for their suitability to adsorb the enzyme urokinase directly from human urine at the outlet of a urinal. Both batch and fixed bed techniques were used for the screening, which identified a phenolic resin (Duolite S-762) as having the best capacity and adsorption efficiency. A capacity in excess of 1800 IU/ml. resin is attainable, and elution with 50% ethanolamine followed by immediate neutralisation with HCl gives satisfactory recovery of activity.     

Recovery of a charged-fusion protein from cell extracts by polyelectrolyte precipitation

Beta-galactosidase served as a model system to explore the feasibility of enhancing the selectivity of a low-cost, easily scaled separation method-precipitation. Enhanced selectivity was sought by fusing the enzyme with polypeptide tails including 5 and 11 aspartates. The unfused protein could not be selectively removed from the Escherichia coli cell extract by precipitation with polyethylenimine (PEI), but the longest fusion could be selectively removed. The presence of nucleic acids limited the purification attainable. Pretreatment with nuclease followed by diafiltration resulted in an extract from which the same fusion could be precipitated with greater than fivefold enrichment, while the untailed enzyme remained unenriched by the same precipitation step. Selectivity is attributed to the binding strength of the polyanionic tails to the polycationic PEI.     

Recovery of aprotinin from insulin industrial process effluent by affinity adsorption

Aprotinin is a protease inhibitor found in bovine organs and used as a valuable human therapeutic compound. In this work, a process for the recovery of aprotinin from insulin industrial process effluent via affinity adsorption on immobilized trypsin and chymotrypsin was developed. First, process conditions were set as a result of a study of the effects of pH and ionic strength on pure aprotinin adsorption and desorption utilizing an experimental design methodology. The best conditions obtained with immobilized trypsin as the ligand were adsorption at 0.018 M NaCl and pH 8.7 and desorption at 0.018 M NaCl and pH 2.1. For immobilized chymotrypsin, the best conditions were adsorption at 0.582 M NaCl and pH 8.0 and desorption at 0.582 M NaCl and pH 2.1. Recovery of the inhibitor from the effluent was carried out utilizing a two-step process: trypsin-agarose adsorption followed by chymotrypsin-agarose adsorption. Analysis of the chromatographic fractions by trypsin and chymotrypsin inhibition and capillary electrophoresis assays strongly suggested that the recovered inhibitor is aprotinin.     

Biologically and chemically mediated adsorption and precipitation of phosphorus from wastewater

1. Download : Download high-res image (340KB)
2. Download : Download full-size image

Highlights? Phosphorus (P) ineffluent can be removed by biological/chemical-driven adsorption and precipitation. ? Phosphorus adsorption by filters and struvite formation are promising options in this field. ? Emerging adsorption approaches include P removal by polymers/nanomaterials.     

Proteomic characterization of novel serum amyloid P component variants from human plasma and urine

Serum amyloid P component (SAP) is a human plasma protein that has been widely studied for its influence on amyloid plaque formation and stabilization. SAP was characterized directly from human plasma and urine samples via novel affinity mass spectrometry-based proteomic technology that is able to readily discriminate between mass-altered protein variants. These analyses were able to identify several variants of SAP that have not been previously reported. These variants include microheterogeneity of the glycan structure, from the loss of one or both terminal sialic acid residues, as well as the loss of the C-terminal valine residue. Moreover, the analysis of urine allowed for the consistent identification of serum amyloid P component as a normal constituent of the urine proteome.     

Properties of human alpha-amylases from urine, pancreas, and saliva

alpha-Amylases from human urine, pancreas, and saliva were purified to homogeneity. Their molecular and catalytic properties were similar with respect to relative molecular masses, stability, and absorbance in neutral solution, but their isoelectric points differed clearly. Salivary amylase was more sensitive than the other two to inhibition by iodoacetate and EDTA, suggesting a less compact structure. The intermediate qualities of the urinary activity were ascribed to the fact that this enzyme originates from other two without major modifications by metabolism. Human alpha-amylase should be considered as a sole enzyme with multiple forms originating from glycosylation and deamidation. There was no evidence for real isoenzymes.     

Recovery of whole plants of sweet orange from somatic embryos subjected to freezing thawing treatments

Freezing/thawing conditions for cryopreservation of somatic embryos of Washington Navel sweet orange (Citrus sinensis (L.) Osb.) were evaluated. No survival of fast-cooled embryos occurred regardless of the thawing method. Embryos subjected to slow cooling at an estimated rate of 0.5°C min^-1 down to –42°C followed by immersion in liquid nitrogen survived. Survival rate depended on the thawing method. An average survival of 30.5% was achieved when frozen embryos were thawed by immersion in a water bath at 37°C. Surviving embryos developed into whole plantlets and no phenotypic abnormalities have been observed during a growth period of four years. Total soluble proteins and peroxidase and esterase isoenzyme analysis did not show differences between treated plants and non-frozen controls.     

Formation of N tau-ribosylhistidine, a novel histidine derivative found in the urine in histidinemia, from histidine and NAD(P)+ catalyzed by an NAD(P)+ glycohydrolase system

The formation of N tau-ribosylhistidine (His-R), a novel histidine derivative found in the urine of histidinemic patients, was studied. A most possible synthetic pathway catalyzed by imidazole acetic acid (ImAA) phosphoribosyltransferase was not substantiated, because p.o. administration to humans and rats of aspirin, an inhibitor of the enzyme, did not change the urinary excretion of His-R, whereas aspirin decreased the excretion of ImAA-R with concomitant increase in that of ImAA. His-R was produced on incubation of a rat liver homogenate or its membrane fraction with histidine, NAD(P)+ and MgCl2, but not with only histidine or NAD(P)+. Nicotinamide inhibited the formation of His-R. Thus the enzymes responsible for the formation of His-R were suggested to be NAD(P)+ nucleosidase, nucleotide pyrophosphatase and 5'-nucleotidase.     

Recovery of ecosystem carbon fluxes and storage from herbivory

The carbon (C) sink strength of arctic tundra is under pressure from increasing populations of arctic breeding geese. In this study we examined how CO₂ and CH₄ fluxes, plant biomass and soil C responded to the removal of vertebrate herbivores in a high arctic wet moss meadow that has been intensively used by barnacle geese (Branta leucopsis) for ca. 20 years. We used 4 and 9 years old grazing exclosures to investigate the potential for recovery of ecosystem function during the growing season (July 2007). The results show greater above- and below-ground vascular plant biomass within the grazing exclosures with graminoid biomass being most responsive to the removal of herbivory whilst moss biomass remained unchanged. The changes in biomass switched the system from net emission to net uptake of CO₂ (0.47 and −0.77 μmol m⁻² s⁻¹ in grazed and exclosure plots, respectively) during the growing season and doubled the C storage in live biomass. In contrast, the treatment had no impact on the CH₄ fluxes, the total litter C pool or the soil C concentration. The rapid recovery of the above ground biomass and CO₂ fluxes demonstrates the plasticity of this high arctic ecosystem in terms of response to changing herbivore pressure.     

Prediction of adsorption from multicomponent solutions by activated carbon using single-solute parameters

The adsorption of 3 barbiturates—phenobarbital, mephobarbital, and primidone—from simulated intestinal fluid (SIF), without pancreatin, by activated carbon was studied using the rotating bottle method. The concentrations of each drug remaining in solution at equilibrium were determined with the aid of a high-performance liquid chromatography (HPLC) system employing a reversed-phase column. The competitive Langmuir-like model, the modified competitive Langmuir-like model, and the LeVan-Vermeulen model were each fit to the data. Excellent agreement was obtained between the experimental and predicted data using the modified competitive Langmuir-like model and the LeVan-Vermeulen model. The agreement obtained from the original competitive Langmuir-like model was less satisfactory. These observations are not surprising because the competitive Langmuir-like model assumes that the capacities of the adsorbates are equal, while the other 2 models take into account the differences in the capacities of the components. The results of these studies indicate that the adsorbates employed are competing for the same binding sites on the activated carbon surface. The results also demonstrate that it is possible to accurately predict multicomponent adsorption isotherms using only single-solute isotherm parameters. Such prediction is likely to be useful for improving in vivo/in vitro correlations.     

Recovery of recombinant beta-glucosidase by expanded bed adsorption from Pichia pastoris high-cell-density culture broth

Methanol limited fed-batch cultivation was applied for production of a plant derived beta-glucosidase by Pichia pastoris. The beta-glucosidase was recovered by expanded bed adsorption chromatography applied to the whole culture broth. The new Streamline Direct HST1 adsorbent was compared with Streamline SP. Higher bead density made it possible to operate at two times higher feedstock concentration and at two times higher flow velocity. The higher binding capacity in the conductivity range 0-48 mS cm(-1) of Streamline Direct HST1 might be caused by the more complex interaction of multi-modal ligand in Streamline Direct HST1 compared to the single sulphonyl group in Streamline SP. Harsher elution condition had to be applied for dissociation of beta-glucosidase from Streamline Direct HST1 due to stronger binding interaction. The 5% dynamic binding capacity was 160 times higher for Streamline Direct HST1 compared to Streamline SP. The yield of beta-glucosidase on Streamline Direct HST1 (74%) was significantly higher than on Streamline SP (48%). Furthermore, beta-glucosidase was purified with a factor of 4.1 and concentrated with a factor of 17 on Streamline Direct HST1 while corresponding parameters were half of these values for Streamline SP. Thus, for all investigated parameters Streamline Direct HST1 was a more suitable adsorbent for recovery of recombinant beta-glucosidase from unclarified P. pastoris high-cell-density cultivation broth.