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Removal of the Acid violet 109 from the textile industry wastewater using an advanced oxidation process
No full textSintetske boje u otpadnoj vodi tekstilne industrije predstavljaju rizik po životnu sredinu. Ove vode mogu se tretirati hemijskim i/ili biološkim tretmanima. Osnovni problem mogu biti generisanje toksičnog mulja, visoki operativni troškovi ili troškovi održavanja. Unapređeni procesi oksidacije pokazuju uspeh uz prihvatljive operativne troškove i troškove održavanja. Cilj rada bio je ispitanje uticaja uslova reakcije na obezbojavanja simulirane otpadne vode primenom Fentonovog reagensa u šaržnom sistemu. Efikasnost je ispitivana na primeru antrahinonske boje Acid violet 109. Ispitivan je uticaj početnih koncentracija gvožđa i vodonik-peroksida pri različitim molskim odnosima.Synthetic dyes in wastewater from the textile industry pose a risk to the environment. These effluents can be treated with chemical and/or biological processes. The main problem can be the generation of toxic sludge, high operating costs or maintenance costs. Advanced oxidation processes show success with acceptable operating and maintenance costs. The aim of the work was to investi-gate the influence of reaction conditions on the decolourisation of simulated wastewater using the Fenton reagent in a batch system. The effectiveness was tested using the example of the anthraqui-none colourant Acid violet 109. The influence of the initial concentrations of iron and hydrogen-peroxide in different molar ratios was tested
Exploring the potential of human placental tissue as a bioink in 3D bioprinting for use in soft tissue engineering applications
No full textDespite their safety, current breast reconstruction techniques post-mastectomy carries
complication risks and do not reduce recurrence rates. Tissue engineering now emphasizes
scaffold development for regeneration, and amniotic membrane (hAM) of the human placenta
has shown promise in skin and cornea repair with demonstrated antitumor properties. This
study aims to develop a 3D bioprintable material using hAM homogenate (hAM-h) to retain
its regenerative and antitumor effects over extended period of time.
Homogenates were prepared according to previously established protocol and then
characterized with flow cytometry, tensiometer, viscometer and zetasizer. Alginates of
different viscosities were mixed with hAM-h to make a biomaterial for extrusion 3D
bioprinting on Cellink BioX bioprinter. Printed bioscaffolds were crosslinked with CaCl2 and
then characterized for their compressive strength and swelling ability. Results showed that
hAM-h samples contained high levels of growth factors (Angiopoietin-2, EGF, FGF, HGF)
and other cytokines. Physical properties (density, surface tension, viscosity) were consistent
across samples, with an average particle size of 192.1 ± 24.95 nm and a polydispersity index
> 0.5, indicating heterogeneity of the sample. All samples had a negative surface charge (< -
30 mV), suggesting moderate stability. Compression tests revealed that highALG-hAM-h
bioscaffolds required more force for 70% deformation than lowALG-hAM-h bioscaffolds and
showed an increase in weight over time, while lowALG-hAM-h decreased.
This research provides valuable findings for preparing printable biomaterial based on
hAM homogenate showing its potential suitability for use in soft tissue engineering
applications
The utilization of hazelnut shells for efficient removal of BR18 azo dye: A comparative study of raw and modified adsorbents
No full textThe textile industry is considered one of the bigest industries globally, but it is also a significant source of environmental pollution, releasing dyes, hazardous metals, and chemicals into wastewater. Among these, azo dyes form the largest group of commercial dyes, representing a substantial environmental concern due to their stable molecular structures. Biowaste offers a sustainable, cost-effective solution for adsorbing pollutants like heavy metals and organic compounds. Hazelnut shells (HS), a by-product of the food industry, are widely available and possess properties that make them ideal for adsorptive applications. This study explores the modification of raw hazelnut shells with citric acid (C6H807) to increase their surface negative charge, thereby enhancing their capacity to adsorb cationic dyes such as Basic Red 18 (BR18). Structural characterization of modified (MHS) and raw hazelnut shells (RHS) was conducted using optical microscopy, ATR-FTIR spectroscopy, XRD, and XRF analysis. Adsorption performance was optimized across various conditions, including initial pH, adsorbent dosage, temperature, and initial dey concentration. The efficiency of BR18 removal onto MHS and RHS was found to be 84.7% and 78.4%, respectively, under optimal conditions (C0=100mg/L, t=85 min and pH 3.6). The isotherm experimental data showed that the Freundlich and Temkin isotherms are the most suitable model for MHS and RHS adsorption, respectively. The maximum adsorption capacities were 80.65 mg/g and 62.11mg/g for the MHS and RHS, respectively. Kinetic studies indicated that the adsorption for both tasted materials followed pseudo-second-order model. Thermodynamic analysis confirmed the adsorption process as spontaneous and endothermic. This research presents modified hazelnut shells as an innovative, eco-friendly adsorbent for removing BR18 dye from aqueous solutions, highlighting a promising application for biowaste in water treatment
Two-phase electro-magneto-fluid dynamics model and its computational fluid dynamics implementation
No full textIn this work, we present a two-phase electro-magneto-fluid dynamics (EMFD) model that merges electromagnetics and fluid dynamics. The model is suitable for use in computational fluid dynamics (CFD) software and was incorporated into OpenFOAM® after deriving appropriate equations that bypassed certain limitations of the software. Currently, there is a lack of even single-phase EMFD models that can be incorporated in CFD software, while simpler models from electrohydrodynamics (EHD) and magnetohydrodynamics (MHD) are being implemented, though they have certain approximations that can limit their applicability. We conclude that the derived EMFD model is applicable and show its quality by implementing it and analyzing the results. We use cases with a droplet and the electrospinning process for verification. The drop deformations obtained were closer to analytical predictions than in the literature for two EHD models, but some oscillations were observed. We compared one simulation to the prediction of an analytical equation from MHD, and good agreement was shown. Finally, we simulate the electrospinning process, and the results were very close to the analytical predictions. We conclude that the implementation can be used for both EHD and MHD cases.The following article has been submitted to/accepted by Physics of Fluids. After it is published, it will be found at [https://doi.org/10.1063/5.0190651].Published version: [https://technorep.tmf.bg.ac.rs/handle/123456789/7348]This is the peer-reviewed version of the following article: Bošković Stefan A, Bugarski Branko. Two-phase electro-magneto-fluid dynamics model and its computational fluid dynamics implementation. in Physics of Fluids. 2024;36(2):022019. [https://doi.org/10.1063/5.0190651
Collective durotaxis along a self-generated mobile stiffness gradient in vivo
No full textA crucial aspect of tissue self-organization during morphogenesis, wound healing, and cancer invasion is directed migration of cell collectives. The majority of in vivo directed migration has been guided by chemotaxis, whereby cells follow a chemical gradient. In certain situations, migrating cell collectives can also self-generate the stiffness gradient in the surrounding tissue, which can have a feedback effect on the directionality of the migration. The phenomenon has been observed during collective durotaxis in vivo. Along the biointerface between neighbouring tissues, heterotypic cell-cell interactions are the main cause of this self-generated stiffness gradient. The physical processes in charge of tissue self-organization along the biointerface, which are related to the interplay between cell signalling and the formation of heterotypic cell-cell adhesion contacts, are less well-developed than the biological mechanisms of the cellular interactions. This complex phenomenon is discussed here in the model system, such as collective migration of neural crest cells between ectodermal placode and mesoderm subpopulations within Xenopus embryos by pointing to the role of the dynamics along the biointerface between adjacent cell subpopulations on the subpopulation stiffness
Greenness of dispersive microextraction using molecularly imprinted polymers
No full textMolecularly imprinted polymers (MIPs) as materials with determined levels of selectivity and specificity for designated analytes have recently gained much attention in various application fields. However, with the growing adoption of green analytical chemistry (GAC) principles, it is essential to investigate the greenness of MIP synthesis and its subsequent application in sample preparation, as well as to evaluate the "green"nature of the developed analytical methodologies, such as dispersive solid-phase microextraction (DSPME). Accordingly, the main objective of this research was to evaluate the greenness of MIP-based glycidyl methacrylate synthesis and MIP use as a DSPME sorbent prior to high-performance liquid chromatography with mass spectrometry (HPLC-MS). The green perspective of MIP-DSPME prior to HPLC-MS was investigated using various analytical metric tools such as the Analytical Eco-Scale, the Green Analytical Procedure Index, and Analytical GREEnness (AGREE). Since these analytical tools are not fully implementable for the assessment of the greenness of the MIP synthesis, some alternative approaches were used to optimize the synthesis parameters to make the MIP DSPME sorbent as close as possible to the GAC principles. The calculated AGREE score (0.62) and 91 points in the Analytical Eco-Scale for the proposed DSPME technique using MIP indicated a high level of greenness
Supplementary material for the article: Ivanovska, A.; Milošević, M.; Lađarević, J.; Jankoska, M.; Matić, T.; Svirčev, Z. ; Kostić, M. A step towards tuning the jute fiber structure and properties by employing sodium periodate oxidation and coating with alginate. International Journal of Biological Macromolecules 2024, 257, 128668. https://doi.org/10.1016/j.ijbiomac.2023.128668
Get PDFThis paper outlines a novel simple protocol for tuning the structure and properties of jute using sodium periodate (NaIO4) oxidation and coating with alginate. When compared to the raw jute, fabrics oxidized with a 0.2 or 0.4 % NaIO4 solution for 30–120 min exhibited an increased aldehyde group content (0.185 vs. 0.239–0.398 mmol/g), a significantly increased negative zeta potential (from − 8.57 down to − 20.12 mV), a slight disruption of fiber crystallinity, 15.1–37.5 % and 27.9–49.8 % lower fabric maximum force and stiffness, respectively. Owing to the removal of hydrophobic surface barrier, decreased crystallinity index and the presence of micropores on thefabrics' surfaces, oxidized fabrics have a 22.3–29.6 % improved ability for moisture sorption compared to raw fabric. Oxidized fabrics characterized by very long wetting times and excellent antioxidant activities (> 98 %), can find applications as hydrophobic packaging materials. To further extend the utilization of jute in biocarpet engineering such as water-binding geo-prebiotic supports, oxidized fabrics were coated with alginate resulting in 7.9–24.9 % higher moisture sorption and 352–660 times lower wetting times than their oxidized counterparts. This modification protocol has never been applied to lignocellulosic fibers and sheds new light on obtaining jute fabrics with tuned structure and properties intended for various applications.Related to: [https://technorep.tmf.bg.ac.rs/handle/123456789/6978]Supplementary material for: [https://doi.org/10.1016/j.ijbiomac.2023.128668
Intraoral administration of probiotics and postbiotics: An overview of microorganisms and formulation strategies
No full textThe last decade provided significant advances in the understanding of microbiota and its role in human health. Probiotics are live microorganisms with proven benefits for the host and were mostly studied in the context of gut health, but they can also confer significant benefits for oral health, mainly in the treatment of gingivitis. Postbiotics are cell-free extracts and metabolites of microorganisms which can provide additional preventive and therapeutic value for human health. This opens opportunities for new preventive or therapeutic formulations for oral administration. The microorganisms that colonize the oral cavity, their role in oral health and disease, as well as the probiotics and postbiotics which could have beneficial effects in this complex environment were discussed. The aim of this study was to review, analyse and discuss novel probiotic and postbiotic formulations intended for oral administration that could be of great preventive and therapeutic importance. A special attention has been put on the formulation of the pharmaceutical dosage forms that are expected to provide new benefits for the patients and technological advantages relevant for industry. An adequate dosage form could significantly enhance the efficiency of these products
Production of prebiotic enriched maple syrup through enzymatic conversion of sucrose into fructo-oligosaccharides
No full textMaple syrup, a popular natural sweetener has a high content of sucrose, whose consumption is linked to different health issues such as obesity and diabetes. Hence, within this paper, the conversion of sucrose to prebiotics (fructo-oligosaccharides, FOS) was proposed as a promising approach to obtaining a healthier, value-added product. Enzymatic conversion was optimized with respect to key experimental factors, and thereafter derived immobilized preparation of fructosyltransferase (FTase) from Pectinex® Ultra SP-L (FTase-epoxy Purolite, 255 IU/g support) was successfully utilized to produce novel functional product in ten consecutive reaction cycles. The product, obtained under optimal conditions (60 ◦C, 7.65 IU/mL, 12 h), resulted in 56.0% FOS, 16.7% sucrose, and 27.3% monosaccharides of total carbohydrates, leading to a 1.6-fold reduction in caloric content. The obtained products` prebiotic potential toward the probiotic strain Lactobacillus plantarum 299v was demonstrated. The changes in physico-chemical and sensorial characteristics were esteemed as negligible
Ударне вести: емпиријске формуле, моларне масе, реакције биосинтезе и термодинамичке особине вирусних честица: биосинтезе и везивања Omicron JN.1 варијанте SARS-CoV-2
No full textBreaking news are usually disturbing. Natural disasters, wars, epidemics, etc., are reported as breaking news. This paper reports a decreased danger of spreading of epidemics caused by the JN.1 variant, since analyses indicate that infectivity of the new variant is decreased compared to most earlier variants, which is confirmed by the number of cases (7500 daily in USA). Moreover, JN.1, despite the great number of mutations, has not been able to achieve the values of Gibbs energy change of biosynthesis (and thus virus multiplication rate) of the Hu-1 wild type. The research shows that infectivity and pathogenicity of the JN.1 variant has not reached worrying size, which means that there is no reason to expect the epidemiologic situation getting worse.Ударне вести су обично узнемирујуће. О природним катастрофама, ратовима, епидемијама, итд. се извештава као о ударним вестима. У овом раду је приказано смањење опасности од ширења епидемија изазваних варијантом JN.1, јер анализе показују да је инфективност нове варијанте слабија у односу на већину ранијих варијанти, што потврђује и број случајева (7500 дневно у САД). Штавише, JN.1 упркос великом броју мутација није успео да постигне вредности промене Гибсове енергије биосинтезе (а самим тим и стопе размножавања вируса) дивљег типа Hu.1. Истраживање показује да инфективност и патогеност варијанте JN.1 није достигла забрињавајућу величину, што значи да нема разлога за очекивање погоршање епидемиолошке ситуације