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1.
Article in English | MEDLINE | ID: mdl-38525556

ABSTRACT

This study investigates biochar as an attractive option for removing pharmaceuticals from wastewater streams utilizing data from various literature sources and also explores the sensitivity of the characteristics and implementation of biochar. ANN 1 was designed to determine the optimal biochar characteristics (Surface Area, Pore Volume) to achieve the maximum percentage removal of pharmaceuticals in wastewater streams. ANN 2 was developed to identify the optimal biomass feedstock composition, pyrolysis conditions (temperature and time), and chemical activation (acid or base) to produce the optimal biochar from ANN 1. ANN 3 was developed to investigate the effectiveness of the biochar produced in ANN 1 and 2 in removing dye from water. Biomass feedstock with a high lignin content and high volatile matter at a high pyrolysis temperature, whether using an acid or base, achieves a high mesopore volume and high surface area. The biochar with the highest surface area and mesopore volume achieved the highest removal percentage. Regardless of hydrophobicity conditions, at low dosages (0.2), a high surface area and pore volume are required for a high percent removal. And with a higher dosage, a lower surface area and pore volume is necessary to achieve a high percent removal.


Subject(s)
Charcoal , Wastewater , Charcoal/chemistry , Neural Networks, Computer , Technology , Pharmaceutical Preparations , Adsorption
2.
Materials (Basel) ; 16(19)2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37834487

ABSTRACT

The presence of dyes in effluents from textile industries has a detrimental effect on aquatic ecosystems as it hinders the process of photosynthesis by reducing the penetration of sunlight. The adsorption capacity of a carbon foam-based iron oxide sorbent obtained from natural sources for the removal of organic methylene blue (MB) dye from water was investigated. The adsorption capacities were examined by batch experiments, wherein the impacts of varying iron content, sorbent dosage, contact time, dye concentration, and characterization were assessed. The physical characteristics and surface morphology of the synthesized carbon foam were also investigated. The carbon precursor and iron oxide precursor were coalesced within a singular container and subjected to carbonization process. This resulted in the formation of a porous structure that is capable of effectively providing support to the iron oxide particles. The carbon foam produced is a self-assembled formation that possesses the characteristic shape and underlying network structure reminiscent of bread. As the number of nanoparticles went up, so did the number of active sites. At elevated temperatures, the interactions between the dye molecules were enhanced, resulting in a more efficient process of dye removal. The magnetite sample exhibited endothermic adsorption, and all other samples exhibited exothermic adsorption. The adsorption of MB onto iron supported by carbon foam did not exhibit intraparticle diffusion as the only rate-limiting step for all samples. The adsorption rate was governed by a multistep elementary reaction mechanism in which multiple processes occurred simultaneously. The experimental data in this study may be accurately modeled by the pseudo-second-order kinetic model (R2 > 0.96). Additionally, the Freundlich isotherm best describes the adsorption equilibrium, which is supported by the outstanding fit of data to the model (R2 > 0.999). The findings suggest that the utilization of a natural carbon foam as a support for an immobilized iron oxide sorbent demonstrates considerable effectiveness in the removal of methylene dye from industrial effluent.

3.
Molecules ; 28(3)2023 Jan 28.
Article in English | MEDLINE | ID: mdl-36770937

ABSTRACT

The potential use of magnetic nanopowder for phenol adsorption mobilised on natural grain carbon foam from an aqueous solution was studied. Phenolic compounds are priority pollutants with high toxicity even at low concentrations. A magnetic nanopowder was synthesised by dissolving an iron sponge in nitric acid to produce iron nitrate, which was added to a natural grain mixture with flour as the main ingredient. The synthesised carbon foam was investigated for the effects of initial concentration, time, and TEM (transmission electron microscopy) characterisation. The phenol adsorption increased as the iron content of the carbon foam and the initial concentration increased. A kinetic study showed that the phenol adsorption data adequately covered all the carbon foam samples tested using an equation corresponding to a pseudo-first order chemical reaction. The Freundlich, Langmuir, and Temkin equations were tested for modelling the adsorption isotherms at equilibrium, and it was concluded that the Temkin model fit the experimental data adequately. Due to its exceptional physical and chemical properties, carbon magnetic nanopowder is regarded as an outstanding pollutant absorber in environmental investigations. R2 values derived from the pseudo-first-order model exceed 0.99. R2 > 0.94 indicates that the Freundlich isotherm provides the best fit to the equilibrium data.

4.
Sci Rep ; 12(1): 20009, 2022 11 21.
Article in English | MEDLINE | ID: mdl-36411315

ABSTRACT

Textile effluents contain dyes that negatively affect water bodies and inhibit photosynthesis by reducing sunlight penetration. This study investigated the adsorption capacity of an iron oxide sorbent immobilised on naturally derived carbon foam for the removal of organic methylene blue dye from water. In this study, the carbon precursor and iron oxide precursor were mixed and carbonised in a single vessel. Baking and carbonization of the natural grain combination produce a porous structure that can act as an effective support for the iron oxide particles. The carbon foam prepared had a self-assembled structure with flour as a basic element. Sorbents of 6 weight (wt)%, 15 wt% iron, and a 0 wt% iron control sample were prepared. Transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) techniques were used to examine the synthesised carbon foam physical properties and surface morphology. The adsorption capabilities were investigated in batch tests by determining the effects of an increase in iron content, sorbent dosage, contact time, and dye concentration. Breakthrough curves were obtained by varying the height of the sorbent bed and varying the flowrate of the dye solution. A higher bed height corresponds to a greater amount of adsorbent. The breakthrough and equilibrium adsorption capacities were found to increase with increasing bed height. When the flow rate is high, the dye solution leaves the column before equilibrium, resulting in shorter breakthrough and saturation times. Higher bed heights and lower flow rates resulted in optimal dye removal in the flow through the system. Breakthrough time increases with increasing iron content. The 15 wt% iron sample displayed superior adsorption capabilities than the 6 wt% sample, while the 0 wt% iron control sample displayed minimal adsorptive capabilities. The pseudo-first order kinetic model was the best fit model for this study (R2 > 0.96), and the adsorption equilibrium is best described by the Freundlich isotherm (R2 > 0.99). The results showed that an iron oxide sorbent immobilised on carbon foam made from natural sources is a good adsorbent for removing methylene dye.


Subject(s)
Coloring Agents , Water Pollutants, Chemical , Adsorption , Coloring Agents/chemistry , Carbon , Water Pollutants, Chemical/chemistry , Water/chemistry , Iron
5.
Molecules ; 27(5)2022 Mar 04.
Article in English | MEDLINE | ID: mdl-35268786

ABSTRACT

The removal of organic pollutants is a major challenge in wastewater treatment technologies. Coagulation by plant proteins is a promising technique for this purpose. The use of these proteins has been experimentally investigated and reported in the literature. However, the determination of the molecular interactions of these species is experimentally challenging and the computational approach offers a suitable alternative in gathering useful information for this system. The present study used a molecular dynamic simulation approach to predict the potentials of using Moringa oleifera (MO), Arachis hypogaea, Bertholletia excelsa, Brassica napus, and Helianthus annuus plant proteins for the coagulation of organic pollutants and the possible mechanisms of coagulation of these proteins. The results showed that the physicochemical and structural properties of the proteins are linked to their performance. Maximum coagulation of organic molecules to the proteins is between 50-100%. Among five proteins studied for coagulation, Brassica napus and Helianthus annuus performed better than the well-known MO protein. The amino acid residues interacting with the organic molecules play a significant role in the coagulation and this is peculiar with each plant protein. Hydrogen bond and π-interactions dominate throughout the protein-pollutants molecular interactions. The reusability of the proteins after coagulation derived from their structural quality analysis along with the complexes looks promising and most of them are better than that of the MO. The results showed that the seed proteins studied have good prediction potentials to be used for the coagulation of organic pollutants from the environment, as well as the insights into their molecular activities for bioremediation.


Subject(s)
Plant Proteins
6.
Sci Rep ; 11(1): 21313, 2021 10 29.
Article in English | MEDLINE | ID: mdl-34716374

ABSTRACT

Lignocellulosic biomass is an important source of renewable energy and a potential replacement for fossil fuels. In this work, the X-ray fluorescence (XRF) method was used to analyze the elemental composition of raw and pretreated lignocellulosic biomass of cassava peels, corn cobs, rice husks, sugarcane bagasse, yam peels, and mixtures of cassava peels and yam peels, corn cobs and rice husks and all five biomass samples combined. The influence of particle size on elemental properties was investigated by screening the selected biomass into two size fractions, of an average of 300 and 435 µm, respectively. The total concentration of Mg, Al, Si, P, S, Cl, Ca, Ti, Cr, Mn, Fe, Co, Cu, Zn, Sn, Ni, Br, Mo, Ba, Hg, and Pb were determined for each of the biomass samples before and after the different pretreatments adopted in this study. From the results of the analysis, there was a significant reduction in the concentration of calcium in all the analyzed biomass after the alkaline pretreatment with rice husks biomass having the lowest concentration of 66 ppm after the alkaline pretreatment. The sulfur content of the acid pretreated biomass increased considerably which is likely due to the sulfuric acid used for the acid pretreatment. The fact that a mixture of biomass feedstock affects the properties of the biomass after pretreatment was validated in the mixed biomass of cassava peels and yam peels biomass as an example. The concentration of Mg in the mixed biomass was 1441 ppm but was 200 ppm and 353 ppm in individual cassava peels and yam peels respectively. The results of this study demonstrated that pretreated mixtures of biomass have varied elemental compositions, which could be an important factor affecting downstream processes, especially if a hybrid feedstock is used in a large-scale application.

7.
J Oleo Sci ; 70(10): 1417-1427, 2021 Oct 05.
Article in English | MEDLINE | ID: mdl-34497183

ABSTRACT

Improvements on energy density of loose biomass such as sugarcane feedstock is crucial in the technology of biomass energy conversion and generation. South Africa is one of the producers and refiners of sugarcane. High energy density of sugarcane bagasse biomass through separation and briquetting is imperative in developing adequate streams and quality energy generation from sugarcane upstream milling processes. Unseparated bagasse and separated fractions of fiber and pith possess energy contents of about: 16.14 MJ/kg, 17.73 MJ/kg and 15.74 MJ/kg respectively. Fiber fractions have high energy content than bagasse and pith which demonstrates that pith fraction from bagasse lowers energy density. However, the use of starch and PVA (Polyvinyl Alcohol) as binders during briquetting contributed no significant difference in the overall energy density of the biomass briquettes produced. In the same vein, the addition of 50% charcoal as the hybrid component significantly improves the energy density and the physical properties of briquettes, biomass fractions of bagasse, fiber and pith to: 19.43 MJ/kg, 19.57 MJ/kg and 18.37 MJ/kg respectively. Fiber fraction remains the biomass fraction with highest energy content as compared to other fractions. After briquetting and drying of briquettes to moisture content below 12%, there was a significant improvement on the burning rate, briquetting, binder, hybridization which does improve the biomass briquettes characteristics. Separation of bagasse is crucial under certain conditions since there are no significance differences in the energy density of bagasse fractions. However, the use of PVA and charcoal does pose the necessity of bagasse separation from its fractions for briquetting.


Subject(s)
Biomass , Cellulose/chemistry , Dietary Fiber , Food Handling/methods , Saccharum/chemistry , Animal Feed/analysis , Cellulose/analysis , Charcoal/chemistry , Chemical Phenomena , Polyvinyl Alcohol/chemistry , South Africa
8.
J Oleo Sci ; 70(7): 1013-1026, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-34121032

ABSTRACT

In this study, hybridized feedstocks (mixtures of biomass) of cassava peels plus yam peels, as well as corn cobs plus rice husks biomass, were optimized using the response surface methodology centered on the statistical design of experiments (DOE) of the Box-Behnken design (BBD), to produce bioethanol. The feedstocks were locally sourced, hybridized (mixed), pretreated, and fermented before being distilled in a UOP3CC continuous distillation column. The BBD was applied using a 3-level, 3-factor process variables using pH, time, and particle size, and indicated as X1, X2, and X3, respectively. The bioethanol yield from the two hybridized biomass feedstocks was predicted by the developed quadratic polynomial models from BBD. For the hybridized biomass mixture of cassava peels plus yam peels, the optimal condition was statistically predicted as pH 5.00, fermentation time of 120.00 hours, and particle size of 362.5 microns, the predicted bioethanol yield under the optimal condition was 115.75 mL per 1500 g of hybridized biomass and the average volume of bioethanol obtained was 125.00 mL per 1500 g of biomass, which is within the projected range of the model equation, same applies to rice husks plus corn cobs hybridized biomass, but with a better prospect for bioethanol production.


Subject(s)
Biomass , Ethanol/isolation & purification , Lignin/metabolism , Biofuels , Dioscorea/chemistry , Distillation , Ethanol/chemistry , Fermentation , Hydrogen-Ion Concentration , Manihot/chemistry , Models, Chemical , Nigeria , Oryza/chemistry , Saccharomyces cerevisiae/metabolism , Time Factors , Zea mays/chemistry
9.
Infect Genet Evol ; 91: 104803, 2021 07.
Article in English | MEDLINE | ID: mdl-33684568

ABSTRACT

Diarrhoea infection is a major global health public problem and is caused by many organisms including diarrheagenic Escherichia coli pathotypes. The common problem with diarrhoea is the drug resistance of pathogenic bacteria, the most promising alternative means of preventing drug resistance is vaccination. However, there has not been any significant success in the prevention of diarrhoea caused by E. coli through vaccination. Epitope-based vaccine is gaining more attention due to its safety and specificity. Sequence variation of protective antigens of the pathogen has posed a new challenge in the development of epitope-based vaccines against the infection, leading to the necessity of multiepitope based design. In this study, immunoinformatics tools were used to design multiepitope vaccine candidates from plasmid genome sequences of multiple pathotypes of E. coli species involved in diarrhoea infections. The ability of the identified epitopes to be used as a cross-protect multiepitope vaccine was achieved by identifying conserved, immunogenic and antigenic peptides that can elicit CD4+ T-cell, CD8+ T-cell and B-cell and bind to MHC I and II HLA alleles. The molecular docking results of T-cell epitopes showed their well binding affinity to receptive protein and with a wider population coverage. The different multiepitope-based vaccines (MEVCs) candidates were constructed and based on the types of epitope linker they contained. The MEVCs exhibited very good binding interactions with the human immune receptor. Among multiepitope vaccines constructed, MEVC6, MEVCA and MEVCB are more promising as potential vaccine candidates for cross-protection against gastrointestinal infections according to the computational study. It is also hoped that after validation and testing, the predicted multiepitope-based vaccine candidates will probably resolve the challenge of immunological heterogeneity facing enteric vaccine development.


Subject(s)
Computational Biology/methods , Diarrhea/prevention & control , Epitopes, T-Lymphocyte/immunology , Escherichia coli Vaccines/analysis , Escherichia coli/physiology , Molecular Docking Simulation , Vaccine Development
10.
Sci Rep ; 11(1): 557, 2021 01 12.
Article in English | MEDLINE | ID: mdl-33436682

ABSTRACT

In the present study, five lignocellulosic biomass namely, corn cobs (Zea mays), rice husks (Oryza sativa), cassava peels (Manihot esculenta), sugar cane bagasse (Saccharum officinarum), and white yam peels (Dioscorea rotundata) of two mesh sizes of 300 and 425 microns and a combination of some and all of the biomass were pretreated using combined hydrothermal and acid-based, combined hydrothermal and alkali-based and hydrothermal only processes. The raw and pretreated biomass were also characterized by Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), X-Ray diffraction (XRD), and Scanning electron microscopy (SEM) to determine the effects of the various pretreatments on the biomass being studied. The cellulose values of the raw biomass range from 25.8 wt% for cassava peels biomass to 40.0 wt% for sugar cane bagasse. The values of the cellulose content increased slightly with the pretreatment, ranging from 33.2 to 43.8 wt%. The results of the analysis indicate that the hydrothermal and alkaline-based pretreatment shows more severity on the different biomass being studied as seen from the pore characteristics results of corn cobs + rice husks biomass, which also shows that the combination of feedstocks can effectively improve the properties of the biomass in the bioethanol production process. The FTIR analysis also showed that the crystalline cellulose present in all the biomass was converted to the amorphous form after the pretreatment processes. The pore characteristics for mixed corn cobs and rice husks biomass have the highest specific surface area and pore volume of 1837 m2/g and 0.5570 cc/g respectively.

11.
Sci Rep ; 10(1): 2400, 2020 02 12.
Article in English | MEDLINE | ID: mdl-32051536

ABSTRACT

Reactive extraction is a significant technique employed for the removal of organic acids such as carboxylic acid which are usually present in low concentrations in aqueous solutions. This technique was explored by applying Response Surface Methodology (RSM) in process parameter optimization for malic acid recovery from aqueous streams using Trioctylamine as extractant and 1-decanol as organic diluent. Malic acid, a C4 dicarboxylic acid has a wide variety of applications in the polymer, food, chemical and pharmaceutical industries. The optimization of the response function: extraction efficiency was systematically carried out using three process parameters for reactive extraction: temperature, initial malic acid concentration and extractant (Trioctylamine) composition. Response Surface Methodology in combination with Box-Behnken design involving seventeen experimental runs was employed for malic acid reactive extraction in this study. A statistical second-order polynomial predicted an extraction efficiency of 97.53%. The optimum conditions of the process variables were found to be: temperature: 304.73 K, acid concentration: 0.25 kmol/m3, Trioctylamine composition: 23.54% (v/v). Under these optimum conditions, the experimental response of extraction efficiency of 93.25% was obtained. The experimental results obtained was in close conformity with the predicted values by numerical optimization using Response Surface Methodology. These findings can pave the way for the reactive separation process design for recovery of carboxylic acids from dilute aqueous waste streams as well as a fermentation broth.

12.
Curr Drug Metab ; 19(13): 1100-1110, 2018.
Article in English | MEDLINE | ID: mdl-30039757

ABSTRACT

BACKGROUND: Essential oils are liquid extracts from aromatic plants, which have numerous applications in multiple industries. There are a variety of methods used for the extraction of essential oils, with each method exhibiting certain advantages and determining the biological and physicochemical properties of the extracted oils. Essential oils from different plant species contain more than 200 constituents which are comprised of volatile and non-volatile components. The application of essential oils as antimicrobial, anticancer, anti-inflammatory and anti-viral agents is due to their effective and efficient properties, inter alia. METHOD: Several advanced (supercritical fluid extraction, subcritical extraction liquid, solvent-free microwave extraction) and conventional (hydrodistillation, steam distillation, hydrodiffusion, solvent extraction) methods have been discussed for the extraction of essential oils. Advanced methods are considered as the most promising extraction techniques due to less extraction time, low energy consumption, low solvent used and less carbon dioxide emission. CONCLUSION: This manuscript reviewed the major research studies in the field and discussed several research findings on the chemical composition of essential oils, methods of oil extraction, and application of these oils in pharmaceutical and therapeutic fields. These essential oils can be used as anticancer, antimicrobial, antiviral, and as skin permeation enhancer agents.


Subject(s)
Oils, Volatile , Plant Extracts , Plant Oils , Animals , Chemistry Techniques, Analytical , Humans , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Oils, Volatile/therapeutic use , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Plant Oils/chemistry , Plant Oils/pharmacology , Plant Oils/therapeutic use
13.
Sci Rep ; 8(1): 477, 2018 01 11.
Article in English | MEDLINE | ID: mdl-29323139

ABSTRACT

Reverse micelles extraction of erythromycin and amoxicillin were carried out using the novel Sophorolipids biosurfactant. By replacing commonly used chemical surfactants with biosurfactant, reverse micelle extraction can be further improved in terms of environmental friendliness and sustainability. A central composite experimental design was used to investigate the effects of solution pH, KCl concentration, and sophorolipids concentration on the reverse micelle extraction of antibiotics. The most significant factor identified during the reverse micelle extraction of both antibiotics is the pH of aqueous solutions. Best forward extraction performance for erythromycin was found at feed phase pH of approximately 8.0 with low KCl and sophorolipids concentrations. Optimum recovery of erythromycin was obtained at stripping phase pH around 10.0 and with low KCl concentration. On the other hand, best forward extraction performance for amoxicillin was found at feed phase pH around 3.5 with low KCl concentration and high sophorolipids concentration. Optimum recovery of erythromycin was obtained at stripping phase pH around 6.0 with low KCl concentration. Both erythromycin and amoxicillin were found to be very sensitive toaqueous phase pH and can be easily degraded outside of their stable pH ranges.


Subject(s)
Anti-Bacterial Agents/chemistry , Liquid-Liquid Extraction/methods , Micelles , Oleic Acids/chemistry , Surface-Active Agents/chemistry , Amoxicillin/chemistry , Amoxicillin/isolation & purification , Anti-Bacterial Agents/isolation & purification , Erythromycin/chemistry , Erythromycin/isolation & purification , Hydrogen-Ion Concentration , Osmolar Concentration , Potassium Chloride/chemistry , Water/chemistry
14.
Curr Drug Metab ; 18(1): 16-29, 2017.
Article in English | MEDLINE | ID: mdl-27654898

ABSTRACT

In clinical studies, drugs with hydrophobic characteristic usually reflect low bioavailability, poor drug absorption, and inability to achieve the therapeutic concentration in blood. The production of poor solubility drugs, in abundance, by pharmaceutical industries calls for an urgent need to find the alternatives for resolving the above mentioned shortcomings. Poor water solubility drugs loaded with polymeric micelle seem to be the best alternative to enhance drugs solubility and bioavailability. Polymeric micelle, formed by self-assembled of amphiphilic block copolymers in aqueous environment, functioned as solubilizing agent for hydrophobic drug. This review discusses the fundamentals of polymeric micelle as drug carrier through representative literature, and demonstrates some applications in various clinical trials. The structure, characteristic, and formation of polymeric micelle have been discussed firstly. Next, this manuscript focuses on the potential of polymeric micelles as drug vehicle in oral, transdermal routes, and anti-cancer agent. Several results from previous studies have been reproduced in this review in order to prove the efficacy of the micelles in delivering hydrophobic drugs. Lastly, future strategies to broaden the application of polymeric micelles in pharmaceutical industries have been highlighted.


Subject(s)
Drug Delivery Systems , Micelles , Nanostructures/chemistry , Polymers/chemistry , Antineoplastic Agents/administration & dosage , Humans
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