Environmental Science
D. Hermanto; N. Ismillayli; H. Muliasari; R. Wirawan; S.R. Kamali
Abstract
BACKGROUND AND OBJECTIVES: To address the potential harm caused by the intensive use of pesticides in pest control in agriculture, there is a need for accurate and efficient methods to detect and monitor pesticide residues. Therefore, this study aimed to develop a biosensor that can detect organophosphate ...
Read More
BACKGROUND AND OBJECTIVES: To address the potential harm caused by the intensive use of pesticides in pest control in agriculture, there is a need for accurate and efficient methods to detect and monitor pesticide residues. Therefore, this study aimed to develop a biosensor that can detect organophosphate pesticides highly toxic to humans and the environment. METHODS: Biosensor organophosphate pesticides using a single film containing acetylcholinesterase/choline oxidase have been designed using silver-based plasmonic nanoparticles as a colorimetric indicator. In the presence of acetylcholinesterase, acetylcholine is hydrolyzed to choline and acetic acid, then choline oxidase catalyzes the oxidation of choline to hydrogen peroxide and betaine. Hydrogen peroxide reacts with the silver nanoparticles, and the discoloration of the brown solution occurs due to the oxidation of silver+.FINDINGS: As a biosensor indicator, silver nanoparticles were extremely accurate, sensitive, and stable over a long period of storage. Transmission Electron Microscope images confirmed the reduction in size of nanoparticles from 16.82 ± 4.36 to 9.63 ± 2.29 nanometers. The analyte profenofos, one of the organophosphate pesticides, inhibits the activity of acetylcholinesterase, thereby reducing the concentration decrease of silver nanoparticles by releasing less hydrogen peroxide. Optimum conditions for biosensors were achieved with a potential of Hydrogen of 7, buffer, and acetylcholinesterase concentrations of 7 and 70 millimolar, respectively, with an incubation time of 5 minutes. Biosensor response showed a linear range at profenofos concentrations of 0.05-2.00 milligrams per liter, with limits of detection and quantization of 0.04 and 0.13 milligrams/liter, respectively. Biosensor also has excellent sensitivity, reproducibility, and stability, with a Relative Standard Deviation of 2.5 percent and a stable response of up to 4 months. Subsequently, using a biosensor in the chilli as a sample resulted in a profonefos level of 0.04 milligrams per liter, making it safe for consumption. CONCLUSION: Biosensor measurement outcome aligned with the gas chromatography-mass spectrometry result, which is the accepted standard method for detecting profenofos. Additionally, the proposed biosensor offers several advantages such as ease of use, fast, low-cost, and on-site analysis. Hence, this method is suitable for monitoring and controlling pesticide residues, particularly organophosphate, in agricultural products and the environment.
Environmental Science
E. Imelda; K. Khairan; R.R. Lubis; T. Karma; R. Idroes
Abstract
BACKGROUND AND OBJECTIVES: Isotoma longiflora L is commonly used as a medicinal plant by the local community in Indonesia, and its geographical position determines its bioactive compounds and hence its efficacy. Ethanol extracts of Isotoma longiflora leaves from various locations in Aceh Province were ...
Read More
BACKGROUND AND OBJECTIVES: Isotoma longiflora L is commonly used as a medicinal plant by the local community in Indonesia, and its geographical position determines its bioactive compounds and hence its efficacy. Ethanol extracts of Isotoma longiflora leaves from various locations in Aceh Province were analyzed using a simple infrared spectroscopy technique combined with chemometrics to determine the effect of geographical location and conditions by classification and authentication.METHODS: Isotoma longiflora leaf samples were collected from Aceh Besar (a geothermal manifestation of Ie Suum), Banda Aceh, Aceh Jaya, Bireun, and Central Aceh. Principal component analysis was used to categorize the ethanol extract of Isotoma longiflora leaves, and a linear discriminant analysis was used for authentication.FINDINGS: The principal component analysis score plot indicated 89 percent of total data variance and that the samples formed three distinct groups: group I consisting of Aceh Tengah and Bener Meriah samples; group II of Aceh Besar and Banda Aceh samples; and group III of Aceh Selatan, Aceh Barat Daya, Aceh Jaya, and Bireun. A linear discriminant analysis was then used to validate these results, and the linear discriminant analysis model derived from the cross-validation predicted the origin of Isotoma longiflora samples with 100 percent accuracy rate.CONCLUSION: The Isotoma longiflora leaf extracts were successfully classified using Fourier-transform infrared spectroscopy data processed through chemometric calculations (namely, principal component analysis). Based on the cross-validation using linear discriminant analysis showed that the prediction model had a 100 percent accuracy. The present study thus revealed the effect of geographical location on the composition of bioactive compounds in Isotoma longiflora, suggesting the potential of chemometric techniques for quality control and assurance in traditional medicine.
Environmental Science
E. Budianto; S.H. Astuti
Abstract
Nifedipine is a hypertension drug must be consumed three times a day due to its low oral bioavailability. One way of developing a controlled drug delivery system is making nifedipine microcapsules by using environmentally friendly polymers of polylactic acid and polycaprolactone via the evaporation method ...
Read More
Nifedipine is a hypertension drug must be consumed three times a day due to its low oral bioavailability. One way of developing a controlled drug delivery system is making nifedipine microcapsules by using environmentally friendly polymers of polylactic acid and polycaprolactone via the evaporation method using oil-in-water solvents. Polylactic acid and polycaprolactone can be said to be environmentally friendly polymers, because they can be degraded naturally in nature both in the biotic, and abiotic environment, or microorganism. In this study, polylactic acid, Polycaprolactone, and nifedipine were dissolved in dichloromethane solvent; then, an emulsifier was added for the emulsification stage. After passing through the dispersion stage for the process of compaction of the microcapsules by solvent evaporation, the microcapsules were filtered. Microcapsules were characterized using particle size analysis, X-ray diffractometry, and scanning electron microscopy, respectively. The drug release percentage was determined by dissolving microcapsules for 55 hours using a buffer at the potential of hydrogen 1.2 and pH 7.4 as dissolution media. In this study, all variations in the composition of polyblend resulted in a percent efficiency of encapsulation ranging from 78.82%-89.84%, and percent release ranging from 6.80%-39.07%. The composition of 100% polylactic acid produces the highest percent encapsulation efficiency of 89.84% but produces the lowest percentage of drug release at 6.80%. The best composition obtained was polylactic acid: polycaprolactone 1:9 (weight per weight), with a percent release of 39.07% and percent encapsulation of 78.82%. Microcapsule solids produced are approximately 96%. Particle Size of microcapsule ranges at 0.5 μM.
Environmental Science
R. Mostafaloo; M. Asadi-Ghalhari; H. Izanloo; A. Zayadi
Abstract
Ciprofloxacin antibiotic that is used to cure several kinds of bacterial infections have a high solubility capacity in water. The influent of ciprofloxacin to water resources in a low concentration affect the photosynthesis of plants, transforms the morphological structure of the algae, and then disrupts ...
Read More
Ciprofloxacin antibiotic that is used to cure several kinds of bacterial infections have a high solubility capacity in water. The influent of ciprofloxacin to water resources in a low concentration affect the photosynthesis of plants, transforms the morphological structure of the algae, and then disrupts the aquatic ecosystem. 75% of this compound is excreted from the body down to the wastewater which should be removed. BiFeO3, a bismuth-based semiconductor photocatalyst that is responsive to visible light, has been recently used to remove organic pollutants from water. In this study, the optimal conditions for removing ciprofloxacin from aqueous solutions by the BiFeO3 process were investigated. Effective parameters namely pH, reaction time, ciprofloxacin initial concentration, BiFeO3 dose, and temperature on ciprofloxacin removal were studied by using response surface methodology. The validity and adequacy of the proposed model was confirmed by the corresponding statistics (i.e. F-values of 14.79 and 1.67 and p-values of 2 = 0.9107, R2adjusted = 0.8492, R2 predicted = 0.70, AP = 16.761). Hence the Ciprofloxacin removal efficiency reached 100% in the best condition (pH 6, initial concentration of 1 mg/L, BiFeO3 dosage of 2.5 g/L, reaction temperature of 30° C, and process time of 46 min).
Environmental Science
M.M. Amin; S. Yousefinejad; M. Dehghani; S. Rahimi
Abstract
Carbamazepine is one of the hydrophilic compounds identified in aquatic environments. Due to toxicity and bio-stability of this psychotropic pharmaceutical in the environment and humans, its removal efficiency and mineralization are important. In this study, synthesized Fe@Fe2O3 nanowires were applied ...
Read More
Carbamazepine is one of the hydrophilic compounds identified in aquatic environments. Due to toxicity and bio-stability of this psychotropic pharmaceutical in the environment and humans, its removal efficiency and mineralization are important. In this study, synthesized Fe@Fe2O3 nanowires were applied to improve Fenton oxidation process using FeCl3.6H2O and NaBH4. The effects of different parameters such as initial pH, H2O2, FeSO4.7H2O, carbamazepine concentrations, oxidation time, and nanowires dose were evaluated using response surface methodology. After scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffract meter analysis, Fe@Fe2O3 morphology was synthesized in the form of nanowires with diameters of about 40-80 nm. The optimum oxidation conditions for carbamazepine were established at pH= 4.3, reaction time of 45.9 min, nanowire dose of 179.4 mg/L as well as H2O2, FeSO4.7H2O and carbamazepine concentrations of 22, 52.2 and 7.7 mg/L, respectively. The oxidation efficiency (99.5%) achieved under the optimum condition, which was determined by the model, was consistent with the efficiency predicted by the model. The multi-parameter models showed good calibration and prediction abilities with R2= 0.922, R2adj= 0.907, R2pred= 0.868. According to the results, the carbamazepine degradation rate increased with the increase of Fe2+ due to the synergistic effect between Fe@Fe2O3 and Fe2+ on the catalytic decomposition of H2O2 and generation of OH•. It was concluded that the Fenton process based on the Fe@Fe2O3 nanowires can increase the carbamazepine oxidation rate in aqueous solutions. This method can also be used as an effective and pre-treatment process in the conventional treatment plants.
Environmental Science
A.R. Karbassi; S. Tajziehchi; H. Khoshgalb
Abstract
Fuel storage tanks are one of the main sources of water pollution as well as loss of crude oil and oil products in refineries. In the process of utilization of these tanks, considerable amounts of hydrocarbons may find their way into the coastal water, which eventually lead to loss of valuable ...
Read More
Fuel storage tanks are one of the main sources of water pollution as well as loss of crude oil and oil products in refineries. In the process of utilization of these tanks, considerable amounts of hydrocarbons may find their way into the coastal water, which eventually lead to loss of valuable hydrocarbons. Oil type, climatic condition and characteristics of oil tanks are among the main variables in computing evaporative losses. The present study brings out the results of a project that was carried out to investigate the adverse effects of oil terminal on coastal waters of Qeshm Island and aims to elaborate on speciation of metals in coastal waters. For this purpose, 12 stations were sampled. Water chemistry software was used to draw Eh-pH diagrams. Along with the speciation of heavy metals, cluster analysis was carried out by MVSP software. According to the results, HSC diagrams showed that Cu and Cd were present as free ions. Lead, manganese, cobalt, zinc and nickel were respectively present as PbOH, MnOH, ZnOH, CoOH and NiOH in the Persian Gulf. Speciation of Cu and Ni was in the form of Cu2O and NiO. Vanadium was also present in combination with hydroxide. Since all the studied elements were within the water stability range, they were stable, and there were no environmental risks of contamination and toxicity. The results of cluster analysis did not show any relation between Eh and pH. This clearly showed that Eh-pH was governed by different mechanisms in coastal waters of Qeshm Island. Vanadium and Ni concentration was governed by pH, while Cu and Cd concentration was controlled by Eh.
Environmental Science
L. Mohammadi; E. Bazrafshan; M. Noroozifar; A.R. Ansari-Moghaddama; A.R. Khazaei Feizabad; A.H. Mahvi
Abstract
The current study aimed to examine the overall feasibility of the use of copper oxide nanoparticles (CuO-NPs) as a catalyst in ozonation process for the removal of benzene from aqueous solutions under experimental conditions. This experimental study was conducted on a laboratory scale reactor in a semi-batch ...
Read More
The current study aimed to examine the overall feasibility of the use of copper oxide nanoparticles (CuO-NPs) as a catalyst in ozonation process for the removal of benzene from aqueous solutions under experimental conditions. This experimental study was conducted on a laboratory scale reactor in a semi-batch mode. The effect of critical operating parameters such factors as pH, concentration of benzene, reaction time and nano-catalyst dose on the removal of benzene was investigated. The samples included with benzene concentrations (10-200 mg/L), pH (3-13), catalyst dose (0.1-0.5 mg), and ozonation time (5-50 min). Findings indicated that the removal of benzene depended on various utilization parameters. The highest efficiency was achieved at reaction time of 50 min, pH of 12, initial benzene concentration of 10 mg/L and catalyst dose of 0.5 g. Among the studied factors, the maximum and the minimum contributions were made by the dose of nanoparticles (83%) and the reaction time (~73%). The software predicted that use of 0.13 g of the catalyst at pH of 12 and ozonation time of 5 min would lead to a removal efficiency of 68.4%. The catalytic ozonation process was able to remove benzene, and addition of CuO-NPs as a catalyst together with the ozonation process increased the benzene removal efficiency. The values of R2 = 0.9972, adjusted R2= 0.9946, and predicted R2 =0.9893 indicated that the model was acceptably predicted by the software and fitted the data obtained in the experiments.
Environmental Science
N.T. Abdel-Ghani; G.A. El-Chaghaby; F.S. Helal
Abstract
In the present study, different activated carbons were prepared from carbonized African beech wood sawdust by potassium hydroxide activation. The activated carbons were characterized by brunauer–emmett–teller, scanning electron microscope, fourier transform infrared spectroscopy, and thermogravimetric ...
Read More
In the present study, different activated carbons were prepared from carbonized African beech wood sawdust by potassium hydroxide activation. The activated carbons were characterized by brunauer–emmett–teller, scanning electron microscope, fourier transform infrared spectroscopy, and thermogravimetric analyzer. The phenol adsorption capacity of the prepared carbons was evaluated. The different factors affecting phenol’s removal were studied including: contact time, solution pH and initial phenol concentration. The optimum phenol removal was obtained after a contact time of 300 min. and at an initial phenol solution pH 7. The maximum removal percentages were determined at 5mg/l initial phenol concentration as 79, 93, 94 and 98% for AC0, AC1, AC2 and AC3; respectively. The adsorption of phenol on African beech sawdust activated carbons was found to follow the Lagergren first order kinetics and the intraparticle diffusion mechanism gave a good fit to the experimental data. The isothermal models applied fitted the experimental data in the order: Langmuir> Dubinin–Radushkevich> Freundlich and Temkin.
Environmental Science
S.A. Bapat; D.K. Jaspal
Abstract
Heavy metals and dyes are major contributors in contamination of water streams. These contaminants enter into our eco- system, thus posing a significant threat to public health, ecological equilibrium and environment. Thus a combined discharge of these contaminants results in water pollution with high ...
Read More
Heavy metals and dyes are major contributors in contamination of water streams. These contaminants enter into our eco- system, thus posing a significant threat to public health, ecological equilibrium and environment. Thus a combined discharge of these contaminants results in water pollution with high chemical oxygen demand, biological oxygen demand, color, particulate matter, suspended particles and odor. The mounting pollution of the water bodies has attracted attention of the researchers towards the development of novel techniques and materials for water pollution. The paper describes the use of such a material Parthenium hysterophorus, a weed, explored for water purification. The potential of the weed has been tested for several heavy metals and dyes as described in this paper. As per literature the weed is capable of showing adsorption tendency up to 90% in certain cases for some heavy metals and dyes. Powdered weed, activated carbon, ash etc. of Parthenium have been employed for the removal process.
Environmental Science
V. K. Gupta; Suhas; I. Tyagi; S. Agarwal; R. Singh; M. Chaudhary; A. Harit; S. Kushwaha
Abstract
Fertilizer plant waste carbon slurry has been investigated after some processing as an adsorbent for the removal of dyes and phenols using columns. The results show that the carbonaceous adsorbent prepared from carbon slurry being porous and having appreciable surface area (380 m2/g) can remove dyes ...
Read More
Fertilizer plant waste carbon slurry has been investigated after some processing as an adsorbent for the removal of dyes and phenols using columns. The results show that the carbonaceous adsorbent prepared from carbon slurry being porous and having appreciable surface area (380 m2/g) can remove dyes both cationic (meldola blue, methylene blue, chrysoidine G, crystal violet) as well as anionic (ethyl orange, metanil yellow, acid blue 113), and phenols (phenol, 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol) fruitfully from water. The column type continuous flow operations were used to obtain the breakthrough curves. The breakthrough capacity, exhaustion capacity and degree of column utilization were evaluated from the plots. The results shows that the degree of column utilization for dyes lies in the range 60 to 76% while for phenols was in the range 53-58%. The exhaustion capacities were quite high as compared to the breakthrough capacities and were found to be 217, 211, 104, 126, 233, 248, 267 mg/g for meldola blue, crystal violet, chrysoidine G, methylene blue, ethyl orange, metanil yellow, acid blue 113, respectively and 25.6, 72.2, 82.2 and 197.3 mg/g for phenol, 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol, respectively
Environmental Science
N.T. Abdel-Ghani; E.S.A. Rawash; G.A. El-Chaghaby
Abstract
The present work was carried out to evaluate the removal of p-nitrophenol by adsorption onto olive cake based activated carbon having a BET surface area of 672 m²/g. The batch adsorption experimental results indicated that the equilibrium time for nitrophenol adsorption by olive cake-based activated ...
Read More
The present work was carried out to evaluate the removal of p-nitrophenol by adsorption onto olive cake based activated carbon having a BET surface area of 672 m²/g. The batch adsorption experimental results indicated that the equilibrium time for nitrophenol adsorption by olive cake-based activated carbon was 120min. The adsorption data was modeled by equilibrium and kinetic models. The pseudo- first and second order as well as the Elovichkinetic models were applied to fit the experimental data and the intraparticle diffusion model was assessed for describing the mechanism of adsorption. The data were found to be best fitted to the pseudo-second order model with a correlation coefficient (R2=0.986). The intraparticle diffusion mechanism also showed a good fit to the experimental data, showing two distinct linear parts assuming that more than one step could be involved in the adsorption of nitrophenol by the activated carbon. The equilibrium study was performed using three models including Langmuir, Freundlich and Temkin. The results revealed that the Temkin equilibrium model is the best model fitting the experimental data (R2=0.944). The results of the present study proved the efficiency of using olive cake based activated carbon as a novel adsorbent for the removal of nitrophenol from aqueous solution.
