Mixture Of Sulfate Research Articles

Inhibition of Oomycetes by the Mixture of Maleic Acid and Copper Sulfate.

Since the protective activity of the Bordeaux mixture against plant disease caused by oomycetes was discovered, copper compounds have been used for more than a century as an effective plant protection strategy. However, the application of excessive copper can cause adverse effects through long-term heavy metal accumulation in soils. Therefore, it is necessary to develop new strategies to reduce or replace copper in pesticides based on organic and low-input farming systems. Organic acids are eco-friendly. In this study, we tested the antifungal and anti-oomycete activity of maleic acid (MA) and copper sulfate (CS) against 13 plant pathogens. Treatment with a mixture of MA and CS showed strong anti-oomycetes activity against Phytophthora xcambivora, P. capsici, and P. cinnamomi. Moreover, the concentration of CS in the activated mixture of MA and CS was lower than that in the activated CS only, and the mixture showed synergy or partial synergy effects on the anti-oomycete activity. Application of a wettable powder formulation of MA and CS mixture (MCS 30WP; 26.67% MA and 3.33% CS) had excellent protective activity in pot experiments with control values of 73% Phytophthora blight on red pepper, 91% damping-off on cucumber, and 84% Pythium blight on creeping bentgrass, which are similar to those of the CS wettable powder formulation (6.67% CS) containing two times the CS content of MCS 30WP. These observations suggest that the synergistic effect of the MA and CS combination is a sustainable alternative for effective management of destructive oomycete diseases.

Compositional Mapping of Europa Using MCMC Modeling of Near-IR VLT/SPHERE and Galileo/NIMS Observations

Abstract We present maps of surface composition of Europa’s anti-Jovian hemisphere acquired using high spatial resolution IFU multispectral data from the SPHERE instrument on the Very Large Telescope (0.95–1.65 μm) and the NIMS instrument on the Galileo orbiter (0.7–5.2 μm). Spectral modeling was performed using a Markov Chain Monte Carlo method to estimate endmember abundances and to quantify their associated uncertainties. Modeling results support the leading–trailing hemisphere difference in hydrated sulfuric acid abundances caused by exogenic plasma bombardment. Water-ice grains are found to be in the 100 μm–1 mm range, with larger grains present on the trailing hemisphere, consistent with radiation-driven sputtering destroying smaller grains. Modeling best estimates suggest a mixture of sulfate and chlorinated salts, although uncertainties derived from the MCMC modeling suggest that it is difficult to confidently detect individual salt abundances with low spectral resolution spectra from SPHERE and NIMS. The high spatial resolution offered by SPHERE allows the small-scale spatial distribution (<150 km) of potential species to be mapped, including ground-based detection of lineae and impact features. This could be used in combination with other higher spectral resolution observations to confirm the presence of these species.

Synergistic behavior of SLS-OPE-10 binary mixtures at their CMC

Abstract The micellation behaviour of mixtures of sodium lauryl sulphate (SLS) and octylphenol ethoxylate-10 (OPE-10) was investigated using tensiometry and dye solubilisation. The interaction parameters for the system were determined using Rubingh’s model for non-ideality and the adsorption parameters were calculated. The surfactant mixture was found to behave synergistically in terms of CMC reduction and dye solubilisation. Furthermore, the mixture appears to mimic the adsorption and micellation properties of OPE-10 more closely than SLS, regardless of composition. With this knowledge, and considering that OPE-10 is typically more expensive than SLS, the formulator can now use only a fraction of the required amount of OPE-10 for a given application (instead of using 100% OPE-10), resulting in high performance yet economical products. It was also found that the said mixture exhibits azeotropic behaviour at a certain fixed composition.

Monitoring the Cd2+ release from Cd-containing quantum dots in simulated body fluids by size exclusion chromatography coupled with ICP-MS.

Quantification of Cd2+ release from Cd-containing quantum dots (QDs) is of fundamental importance to elucidate its toxicity to organisms, but remains a great challenge due to the lack of appropriate analytical method. Herein, a facile method based on size exclusion chromatography (SEC) combined with inductively coupled plasma mass spectrometry (ICP-MS) was developed for separating and quantifying the QDs and counterpart ions. By using the mixture of sodium dodecyl sulfate (SDS) and ethylenediaminetetraacetic acid tetrasodium salt (EDTA) as the mobile phase, the defect of QD and ion adsorption onto the SEC column was overcome, thus realizing the accurate quantification of ionic species. Besides, the concentration of QDs was achieved through subtracting the ion concentration from the total concentration. Selecting CdSe@ZnS as the typical QDs, the Cd2+ release process in four typical simulated body fluids, namely, simulated gastric fluid, simulated sweat, Gamble's solution, and artificial lysosomal fluid, was monitored using the developed SEC-ICP-MS method. The media pH is identified as the decisive factor which controls the dissolution of ZnS shells and also the Cd2+ release kinetics and final concentration. Our results suggest that the oral pathway for QD uptake poses the biggest risk to human health.

Understanding Haze: Modeling Size-Resolved Mineral Aerosol from Satellite Remote Sensing

Mineral dust aerosols are composed of a complex mixture of silicates, carbonates, oxides, and sulfates. The minerals’ chemical composition and size distribution are vital parameters to evaluate dust environmental impacts. However, the quantification of minerals remains a challenge due to the sparse in situ measurements of dust samples. Here we derive the size-resolved mineralogical composition of airborne dust aerosols from MODIS (Terra and Aqua) satellite-acquired optical measurements and compare it with chemically analyzed elemental (Al, Fe, Ca, Mg) concentrations of aerosols for PM2.5 and PM10 from Chonburi, Chiang Rai, and Bangkok in Thailand, and from Singapore. MODIS-derived mineral retrievals exhibited high correlations with elemental concentrations with R2 ≥ 0.84 for PM2.5 and ≥0.96 for PM10. High mineral dust activity was detected in the vicinity of biomass-burning areas with gypsum and calcite exhibiting tracer characteristics of combustion. The spatiotemporal pattern of the MODIS-derived minerals matched with Ozone Monitoring Instrument (OMI)-derived dust, sulfates, and carbonaceous aerosols, indicating the model’s consistency. Variation in aerosol loading by ±90% led to deviation in the mineral concentration by <10%. An uncertainty of 6.4% between AERONET-measured and MODIS-derived AOD corresponds to a < ± 2% uncertainty in MODIS-derived mineral concentration, demonstrating the robustness of the model.

Molecular insights into the effect of anionic-nonionic and cationic surfactant mixtures on interfacial properties of oil-water interface

The influence of surfactants is of great importance to the interfacial properties, which is related by the characteristics of molecular arrays at the interface of multicomponent and multiphase systems. Comparing with single type of surfactant, the mixtures of surfactants usually provide superior performances in improving interfacial properties of the oil-water interface in the application of enhanced oil recovery. In this study, molecular dynamics simulations were employed to explore the mechanisms and interfacial behaviors at the microscopic level of pure and binary mixture of anionic-nonionic surfactant alcohol ether sulfates (AES) and cationic surfactant dodecyltrimethylammonium chloride (DTAC) at oil-water interface. The results show that the sulfate groups of AES molecules could attract DTAC molecules in the mixed surfactants, thereby reducing the repulsion between the molecules. DTAC molecules present excellent molecular interfacial behaviors, which could improve the arrangement of AES molecules through the interactions between head groups. In addition, it is found that the number of ethylene oxide (EO) group of AES molecules has a great influence on the behaviors of interface. An increase of EO group number could cause AES molecules to exhibit varying degrees of bending. By controlling the proper number of EO group, the aggregation of surfactants could be avoided and satisfactory interfacial properties will be achieved. Moreover, it is observed that the positive charge of DTAC molecule shows a strong repulsion to salt ions, for example Ca2+ ions, thus enhancing the overall salt resistance of mixed surfactants. The molecular-level insights gained in this work could provide useful guidance for designing the surfactant formulations for tertiary/enhanced oil recovery in low-permeability unconventional reservoirs.

Complex processing of titanium-containing mineral raw materials using a mixture of hydrodifluoride and ammonium sulfate

Complex processing of titanium-containing mineral raw materials using a mixture of hydrodifluoride and ammonium sulfate

Comparison of a novel combination of bio-organic fertilizers vis-à-vis a chemical fertilizer

Plant nutrients are essential for the production of healthy crops for the world’s expanding population and thus, they are a vital component of sustainable agriculture. Increased crop production depends on the type of fertilizers used to supplement essential nutrients for plants. The nutrient level fertilizers provide depends on their nature- each type of fertilizer has its advantages and disadvantages concerning crop growth and soil fertility. The management of using fertilizer must aim to ensure both an enhanced and safeguarded environment. Thus, a balanced fertilization strategy must be implemented. An experiment was conducted under field conditions to assess the effects of combinations of bio-fertilizers on agronomic and quality criteria of Brassica juncea (brown mustard), Basella alba (climbing spinach), and Amaranthus dubius (red spinach). Randomized block design with three replicas were used for the study, one set with the application of fertilizers containing Azotobacter, Rhizobium, Sesbania, Bacillus subtilis, Bacillus cereus, Bacillus megaterium, Pseudomonas fluorescens and Glomus (Mycorrhizal inoculant)- under bio-fertilizer; another with a mixture of urea, Potassium Nitrate, Super Phosphate, Potassium Sulfate, and Maple EM solution as chemical fertilizer and a control (water). Results indicated that yield and other plant criteria like chlorophyll content and gel volume were enhanced in bio-fertilizer treated plants compared to the plants grown with chemical fertilizer and control. In general, the application of bio-fertilizer significantly increased leaf length by 16-50%, the total number of leaves by 50-80%, plant size 19.15-63.15%, and gel volume by 147% (approximately) in comparison with untreated plants.

The Homodigital Propeller Flap: A New Tool for Fingertip Reconstruction. Surgical Technique, Anatomical Study, and Clinical Relevance.

An ideal flap for fingertip injuries should cover a significant loss of substance and avoid joint flexion to prevent later contracture and joint stiffness. In this study, the authors describe a modified homodigital island flap-the homodigital propeller flap-to better meet these requirements. An anatomical model of fingertip loss is used to analyze the advancement achieved without flexion of the finger. Twenty-four fresh-frozen fingers were dissected. Wires were inserted to maintain joints in extension. The skin paddle was similar in location to a homodigital island flap. The neurovascular bundle was dissected without exceeding the proximal interphalangeal joint and was released from the proximal half of the paddle. Then, the homodigital propeller flap was rotated 180 degrees to cover the defect. A mixture of India ink and barium sulfate was injected into the pedicle artery after the release of the proximal half of the flap from the neurovascular pedicle to assess residual flap vascularization. India ink highlights the residual subcutaneous vascularization network of the cutaneous paddle. A radiographic study of the flap was then performed to visualize the subcutaneous vascular network of the cutaneous paddle. The homodigital propeller flap achieved an average cutaneous advancement of 18 mm (range, 15 to 22 mm) and allowed full coverage of cutaneous defects for all fingers while maintaining the proximal interphalangeal joint in strict extension. The homodigital propeller flap is a refinement of the classic homodigital island flap. It allows efficient coverage of fingertip defects because of a large advancement without flexion of the finger, reducing the risk of stiffness.

Shock experiments on basalt—Ferric sulfate mixes and their possible relevance to the sulfide bleb clusters in large impact melts in shergottites

AbstractLarge impact‐melt pockets in shergottites contain both Martian regolith components and sulfide/sulfite bleb clusters that yield high sulfur concentrations locally compared to bulk shergottites. The regolith may be the source of excess sulfur in the shergottite melt pockets. To explore whether shock and release of secondary Fe‐sulfates trapped in host rock voids is a plausible mechanism to generate the shergottite sulfur bleb clusters, we carried out shock recovery experiments on an analog mixture of ferric sulfate and Columbia River basalt at peak pressures of 21 and 31 GPa. The recovered products from the 31 GPa experiment show mixtures of Fe‐sulfide and Fe‐sulfite blebs similar to the sulfur‐rich bleb clusters found in shergottite impact melts. The 21 GPa experiment did not yield such blebs. The collapse of porosity and local high‐strain shear heating in the 31 GPa experiment presumably created high‐temperature hotspots (~2000 °C) sufficient to reduce Fe3+ to Fe2+ and to decompose sulfate to sulfite, followed by concomitant reduction to sulfide during pressure release. Our results suggest that similar processes might have transpired during shock production of sulfur‐rich bleb clusters in shergottite impact melts. It is possible that very small CO presence in our experiments could have catalyzed the reduction process. We plan to repeat the experiments without CO.

Surfactant Penetration into Human Skin from Sodium Dodecyl Sulfate and Lauramidopropyl Betaine Mixtures.

Surfactant mixtures are used in a variety of personal care and cosmetic applications but are known to be harsh on the skin. The purpose of this study was to examine anionic surfactant penetration into human skin from nonideal surfactant mixtures under short-time exposure conditions that are relevant to realistic exposure scenarios. This was done by measuring the penetration of a radiolabeled probe (14C-SDS) into human cadaver skin in Franz diffusion cells in vitro from the mixtures of sodium dodecyl sulfate (SDS) and lauramidopropyl betaine (LAPB). Monomer and micelle concentrations in the SDS/LAPB/14C-SDS mixtures were predicted using a regular solution theory approximation. We confirmed that the mixtures of SDS and LAPB exhibit nonideal behavior with a net attraction between the two surfactants. Penetration of 14C-SDS into excised human skin from the mixtures of SDS and LAPB was found to decrease in a log-linear manner with increasing mole fraction of LAPB in the bulk solution (R2 = 0.97, p < 0.001). Additionally, the penetration of 14C-SDS into excised human skin from the mixtures of SDS and LAPB was found to correlate linearly and strongly with the predicted values of 14C-SDS monomer concentration in SDS/LAPB/14C-SDS mixtures (R2 = 0.95, p < 0.01). 14C-SDS penetration from the mixed surfactant composition could be quantitatively reconciled with that from an SDS-only composition by postulating a secondary, positive contribution from LAPB related to its own penetration and binding to skin components that increased SDS penetration at low concentrations. This research therefore supports a monomer penetration theory of surfactant penetration into the skin, combined with a measurable impact of favorable surfactant interactions within the tissue.

Mass transfer process and separation mechanism of sulfuric acid and aluminum sulfate mixture based on IEC technology: Modeling

Ion exclusion chromatography (IEC) is an efficient technique used for the separation of strong electrolytes from weak electrolytes and nonelectrolytes. This work focuses on the assessment of mass transfer process and separation mechanism of H2SO4 and Al2(SO4)3 on the strong base quaternary ammonium I anion exchange resin A-853E. A dynamic model for IEC was proposed and explicitly taken into account the Donnan equilibrium. The result showed that Donnan effect played a significant role in the mass transfer process of ionic species, which was interpreted as the inability of co-ion (Al3+) to pass through Donnan membrane, while the counterion (SO42-) can enter resin pores due to electrostatic attraction. Meanwhile, a column model, based on Donnan equilibrium and cooperative adsorption isotherm, was then developed. The model successfully predicted the concentration profiles of mixed-ion (Al3+ and SO42-) at the outlet of the fixed-bed in the dynamic separation process. The results indicated that the Al3+ promoted the adsorption of SO42- on the resin in view of presence of ‘concentration’ phenomenon. The separation mechanism of Al3+ and SO42- was presented combining model prediction and experimental results. Finally, the influence of three different valence states of metal ions (Na+, Fe2+, Al3+) on the degree of H2SO4 ‘concentration’ was investigated to further verify the Donnan effect.

Effect of thickness on charge transfer properties of conductive polymer based PEDOT counter electrodes in DSSC

Poly(3,4-propylenedioxythiophene (PEDOT) counter electrodes are considered to be one of the most promising alternatives to expensive Pt-based counter electrodes in dye sensitized solar cells (DSSC). In the present study, we prepared PEDOT counter electrodes with various thicknesses through scalable electropolymerization technique using a nontoxic mixture of sodium dodecyl sulfate (SDC) in water medium, which provides the opportunity for scale up and commercialization. The time scale for electropolymerization was varied systematically to tune the thickness and uniformity of PEDOT film. The PEDOT films and their interaction with conventional iodide/triiodide​ (I−/I3−) electrolyte was studied using various electrical and optical characterization techniques. The catalytic activity of porous PEDOT films were found to be decreasing with an increase in thickness. DSSCs fabricated using PEDOT counter electrodes having lower thickness of 33 nm (deposited with 5 s polymerization time) showed superior power conversion efficiency of 10.39%, followed by PEDOT counter electrodes having 65 nm and 120 nm thickness deposited with polymerization time of 10 s and 15 s delivering power conversion efficiencies of 8.11% and 7.45% respectively. Electrochemical Impedance Spectroscopy (EIS) was used to investigate the role of variation in PEDOT thickness with various charge transfer processes at the electrolyte/counter electrode interface influencing PV performance.

Dependence of productivity of white lupine seeds on the foliar dressing with macro- and micronutrient fertilizers

The paper presents the results of the studies on the determination of the effect of foliar dressings with macro- and micronutrient fertilizers on linear growth, the mass of air-dry matter of plants, leaf surface, the formation of a symbiotic apparatus and the yield of seeds of white lupine (Lupinualbus L.) in the conditions of black soils of the Central Black Earth region of the Russian Federation. The field experiments were carried out in 2018-2020 at the Department of Crop production, Breeding and Horticulture of Belgorod State Agrarian University. The object of the research is a high-intensity variety of white Degas lupine. The subject of the research is microfertilizer Aquamix-TV, potassium sulfate fertilizer (K2SO4), phosphate-potassium monophosphate fertilizer (KH2PO4). The weather during the years of the experiments was hot and dry. During the critical periods of the development of lupine plants, a moisture deficit was observed with the excess of heat. The soil cover of the experimental site was represented by a typical medium-thick low-humus heavy loamy black soil with a granulometric composition. The accounting area of the plot was 18 m2, the replication was fourfold and the placement was systematic. The experiment included six variants: control (without fertilizers), foliar dressing with Aquamix-TV micronutrient fertilizer, foliar dressing with potassium sulfate solution, foliar dressing with potassium monophosphate solution, foliar dressing with Aquamix-TV + potassium sulfate mixture and foliar dressing with Aquamix-TV + monophosphate mixture potassium. The analysis of the obtained data showed that the highest yield of seeds of white lupine variety Dega was obtained on variants with foliar dressing with micronutrient fertilizer Aquamix-TV in combination with potassium sulfate and monopotassium phosphate, which amounted to 3.52 and 3.51 t / ha, respectively, which is 0.52 and 0.51 t / ha or 17.3 and 17.1% more than the control variant.

Use of Nano Technology (Nano Gro) To Boost Productivity and Increase Pest Resistance in Okra Crop for Export in Southern Honduras.

The present study reports the effect of the nanotechnology molecule “Nano Gro” on a number of agronomical variables of okra, Abelmoschus esculentus, as well as its effect on leaf miner, white fly, Bemisia tabaci, and Spodoptera larvae attacking the crop. Most initial data was taken in a trial used for the registration of Nano Gro as an agricultural amendment in Honduras, carried in a plot worked by Juan Benito Guevara, a local okra producer farming in Las Bazas, very near the city of Choluteca, next to the Choluteca river, in Southern Honduras. However, other important data was taken on plots from different local okra companies and producers in the Choluteca area. The stimulant Nano Gro is a mixture of sulfates and elements such as Fe, Co, Al, Mg, Mn, Ni and Ag, produced at a concentration of 10-9 mol, available in the form of an oligosacharid pellet. It has OMRI certification and can be used in organic and regular agriculture. According to the Honduran distributor (Núcleo Agro), Nano Gro stimulates the plant´s natural resistance to abiotic stress, which in turn makes the plant produce growth hormones like auxins, gibberellines and cytokinines. This hormone productionmakes the use of nutrients and water more efficient, resulting in greater plant resistance, greater performance and greater quality of fruit harvested.

Obtaining Caustic Soda and Burkeite by Caustification of Mixture of Corbonate and Sodium Sulphate

The optimal technological parameters for the production of caustic soda from sodium carbonate and sulfate and calcium hydroxide have been established. The influence of the concentration of lime milk on the rate of filtration by sediment and filtrate has been studied.&#x0D; Purpose of the Work: The purpose of this work is to determine the physicochemical basis for the production of sodium hydroxide and burkeite by causticization of sodium carbonate and sulfate.&#x0D; Scientific Novelty: In comparison with the known works, a theoretical profoanalytical analysis of the one-cation of four-component system and its constituents was carried out for the first time, and also determined the optimal technological parameters of causticization of solutions for local carbonates and sodium sulfates.&#x0D; Features of the Work:&#x0D; - the influence of the main technological parameters on the processes of causticization, filtration, evaporation;&#x0D; - research of intermediate and finished products by modern physicochemical methods;&#x0D; - study of the rheological properties of the solution depending on the temperature and concentration of the resulting solutions.

Impact of ethanol and NaCl on the acid yellow dye mediated self-aggregation of sodium dodecyl sulfate: A combined investigation by conductivity and molecular dynamics simulation

Herein, we report the micellization behavior of the mixture of sodium dodecyl sulfate (SDS), and acid yellow (AY) dye in water, water + ethanol, and water + NaCl media. The degree of interaction between SDS and AY has been assessed quantitatively from the estimated values of critical micelle concentration (cmc). Three cmc values were observed for the AY + SDS systems at each temperature and solvents utilized, which exhibit a reversed U-shaped variation with respect to the change of temperature in aqueous/NaCl solution while increased monotonically in ethanolic medium almost in all cases. The extent of micellization was found to be disfavored in presence of AY dye. The micellization was also found to be disfavored up to 15% ethanol and favored in the addition of electrolyte species. The values of counterion binding were found to be temperature dependent. The Gibbs free energy (ΔGmo), which was found negative, reveal a spontaneous micellization of AY + SDS system. The other thermodynamic parameters, like enthalpy (ΔHmo) and entropy (ΔSmo) of micellization along with different transfer energies, were also assessed to have an insight on the mode of interaction of surfactant and dye assemblies. The molecular level interaction between SDS and AY has been unveiled by Molecular Dynamics (MD) simulation and exhibits good agreement with experimental results.

Study the Effect of Weight Fractions of Different Powders on the Attenuation Performances of the Epoxy Composite

Among all types of radiation, X-ray has always garnered the most interest, owing to the growing availability of X-ray tubes in industry, research institutions, and medical facilities. In this research, the linear (μl) and mass (μm) attenuation coefficient, half value layer (HVL) and mean free path (λ) of the epoxy polymer-based composites which includes both lead oxide (Pb3O4), mixture of (Fe2O3 + Pb3O4) and barium sulfate (BaSO4) with different weight percentages were determined experimentally for the incident photon energies of (29-35 kV) emitted from (X-rays) source. The dispersion of the filler was also investigated using a scanning electron microscope to examine the composites morphology. The obtained results showed that adding these powders to epoxy has an effect on the X-ray shielding abilities of the prepared composites, meaning that there is a direct relationship between the weight ratios of the composite material with the linear (μl) and mass (μm) attenuation coefficient, and an inverse relationship with the half value layer (HVL) and free path rate (λ). While changing the X-ray shield with applied voltages showed a behavior opposite to what was mentioned above. The result also shows that the lead oxide (Pb3O4) composites yield better attenuation performance than the pure epoxy and the other two composites, especially at high weight fraction (50 Wt.%) of this filler, which due to the high density of these fillers and fine dispensability in the polymer matrix.

Inhibitory Effects of Ternary Mixtures of Sodium Dodecyl Sulfate and Heavy Metals to Acinetobacter seifertii from Otamiri River Sediment in Southeastern Nigeria

Toxicities of sodium dodecyl sulfate (SDS) and heavy metals, Pb(II), Cd(II), Ni(II), Zn(II) and Co(II), as individuals and ternary mixtures of two heavy metals and SDS to Acinetobacter seifertii isolated as preponderant bacterium from Otamiri river sediment, were assessed, using inhibition of dehydrogenase activity as end point. Among the individual toxicants, the EC50S observed ranged from 0.011 ± 0.000 mM for Cd(II) to 2.810 ± 0.140 mM for SDS. The EC50S of the toxicants were statistically different from one another and the order of increasing toxicities were SDS &gt; Ni(II) &gt; Pb(II) &gt; Zn(II) &gt; Co(II) &gt;Cd(II). The responses of the bacterium were concentration -dependent. Arbitrary (ABCR) and EC50 equieffect (EECR) fixed ratio mixtures were used to evaluate the combined toxicities of the toxicants. The concentration-response relationships of all mixtures and individual toxicants were sigmoidal and fitted with logistic function. The observed toxicities (EC50S) were compared with toxicities predicted from concentration addition (CA) and independent action (IA) models. In ABCR1 and ABCR3 mixture ratios of SDS+Ni(II)+Cd(II) and SDS+Co(II)+Cd(II) ternary mixtures, both CA- and IA-predicted EC50S were not statistically different from each other. Furthermore, in all ternary mixtures, both models underestimated the mixture toxicities to A. seifertii, except in ABCR1 of SDS+Ni(II)+Cd(II) mixture, where both models almost correctly predicted the toxicities. Basically, synergistic interaction of the mixture components observed against A. seifertii, indicates their possible toxicological effects on the bacterial population of the aquatic ecosystems.

Toxicity assessment and detection of benzene extracted from wastewater by saponin biosurfactant using luminescence biosensor

AbstractIn this research, benzene, a toxic compound encountered in industrial wastewater, was extracted using a mixture of saponin and sodium dodecyl sulfate (SDS) as anionic surfactants. Also, a biosensor system for assessment of toxicity and detection of extracted benzene was designed using the Luc strains of luminescent Escherichia coli. Results showed saponin and SDS were synergistic for the extraction of benzene. An optimal hydrophilic–lipophilic balance value for extraction was determined to be about 24.1, representing a mixture of 40 wt% SDS and 60% saponin. Under optimal conditions, the concentration of extracted benzene in extraction phase reached 27 ppm. When extracted benzene solution was injected into the biosensor system, the luminescence level of biosensor decreased dramatically, reflecting toxicity. The concentration of benzene in the extracted solution correlated well with toxicity levels measured by the biosensor system. Using the luminescence biosensor system, the half‐maximal effective concentration (EC50) value of benzene was about 26.2 ppm. Our results demonstrate that the designed biosensor system has good sensitivity for toxicity assessment of extracted benzene, and therefore can be proposed as an approach to detect of benzene and other toxic compounds in wastewater.