Abstract This study investigates the effect of ambient conditions change on mint leaves solar drying performance and product water activity. Two drying methods, active indirect solar drying (AISD) and open sun drying (OSD) were compared while the experiments were carried out at specific dry climate conditions. During the experimental days, temperature varied from 20 to 30 °C, air relative humidity from 14 to 28.8 % and ambient pressure was around 82 kPa. The effect of air relative humidity change during the day on the rehydration of the product during the drying process was observed. After 7 h of drying, moisture content of mint leaves decreased from 85.29 % to 5.38 % in the AISD and 7.42 % in the OSD system. The 0.97 initial water activity decreased to 0.195 in AISD and 0.79 in OSD. Rehydration during the evening hours caused an increase in product water activity from 0.2 to 0.51. Changes of ambient conditions such as temperature and air relative humidity during the day can significantly affect water activity of dried product due to its rehydration and thus increase the risk of product spoilage.
{"title":"Effect of ambient parameters change on mint leaves solar drying","authors":"A. Noori, Mohammad Jafar Royen, J. Haydary","doi":"10.2478/acs-2021-0003","DOIUrl":"https://doi.org/10.2478/acs-2021-0003","url":null,"abstract":"Abstract This study investigates the effect of ambient conditions change on mint leaves solar drying performance and product water activity. Two drying methods, active indirect solar drying (AISD) and open sun drying (OSD) were compared while the experiments were carried out at specific dry climate conditions. During the experimental days, temperature varied from 20 to 30 °C, air relative humidity from 14 to 28.8 % and ambient pressure was around 82 kPa. The effect of air relative humidity change during the day on the rehydration of the product during the drying process was observed. After 7 h of drying, moisture content of mint leaves decreased from 85.29 % to 5.38 % in the AISD and 7.42 % in the OSD system. The 0.97 initial water activity decreased to 0.195 in AISD and 0.79 in OSD. Rehydration during the evening hours caused an increase in product water activity from 0.2 to 0.51. Changes of ambient conditions such as temperature and air relative humidity during the day can significantly affect water activity of dried product due to its rehydration and thus increase the risk of product spoilage.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49619935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Corrosion layers of an iron artefact were characterized to study long-term exposition of iron in Slovakia. The iron artefact from Bratislava castle has been coated with a strong layer of corrosion products and masonry residues. Corrosion products were characterized by different methods including energy-dispersive X-ray spectroscopy (EDX), X-Ray diffraction (XRD), and µ-Raman Spectroscopy. Magnetite and goethite on the surface are confirmed typical corrosion products from long-term atmospheric exposure in environment with corrosivity category C-2 (low).
{"title":"Identification of corrosion products on iron artefact from Bratislava castle","authors":"R. Košťúr, M. Zemanová","doi":"10.2478/acs-2021-0001","DOIUrl":"https://doi.org/10.2478/acs-2021-0001","url":null,"abstract":"Abstract Corrosion layers of an iron artefact were characterized to study long-term exposition of iron in Slovakia. The iron artefact from Bratislava castle has been coated with a strong layer of corrosion products and masonry residues. Corrosion products were characterized by different methods including energy-dispersive X-ray spectroscopy (EDX), X-Ray diffraction (XRD), and µ-Raman Spectroscopy. Magnetite and goethite on the surface are confirmed typical corrosion products from long-term atmospheric exposure in environment with corrosivity category C-2 (low).","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42446661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Lactic acid is a biologically important organic acid existing in two enantiomeric forms which are differently metabolized in the human body. In this paper, direct chiral separation of lactic acid by high performance liquid chromatography is presented. Five chiral stationary phases based on macrocyclic antibiotics were used for enantioseparation and chromatographic parameters, such as retention factors, resolution and selectivity factors, were determined under different column temperatures ranging from 5 to 45 °C. Optical isomers of lactic acid were efficiently separated using chiral stationary phases based on teicoplanin (RS = 1.9 ) and ristocetin (RS = 1.7 ) in reversed-phase separation mode at the column temperature of 25 °C.
{"title":"Stationary phase type and temperature effect on HPLC separation of lactic acid enantiomers","authors":"Laura Jánovová, K. Hroboňová","doi":"10.2478/acs-2021-0008","DOIUrl":"https://doi.org/10.2478/acs-2021-0008","url":null,"abstract":"Abstract Lactic acid is a biologically important organic acid existing in two enantiomeric forms which are differently metabolized in the human body. In this paper, direct chiral separation of lactic acid by high performance liquid chromatography is presented. Five chiral stationary phases based on macrocyclic antibiotics were used for enantioseparation and chromatographic parameters, such as retention factors, resolution and selectivity factors, were determined under different column temperatures ranging from 5 to 45 °C. Optical isomers of lactic acid were efficiently separated using chiral stationary phases based on teicoplanin (RS = 1.9 ) and ristocetin (RS = 1.7 ) in reversed-phase separation mode at the column temperature of 25 °C.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49493480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Svetlana Schubertová, Zuzana Burčová, M. Greifová, Marianna Potočňáková, Lívia Janotková, František Kreps
Abstract The aim of the article was to investigate the effect of sea buckthorn juice addition on the growth of microbial cultures in growth medium and juice mixtures. Pure sea buckthorn juice was found to inhibit the growth of all 11 monitored microbial cultures. Lactobacillus plantarum CCM 7039, Lactobacillus plantarum K816, Lactobacillus brevis CCM 1815 and, to a lesser extent, the probiotic strain Lactobacillus rhamnosus GG, grew in a growth medium containing a 25 % addition of sea buckthorn juice. Lactobacillus plantarum K816 and Lactobacillus brevis CCM 1815 grew better in this mixture than in pure growth medium. Moreover, we focused on finding a suitable ratio of sea buckthorn and apple juice for Lactobacillus plantarum CCM 7039, leading to malolactic fermentation, which results in an increase in the pH value and an improvement in the sensory properties of juices. The intention was to incorporate the highest possible addition of sea buckthorn juice while maintaining the viability of Lactobacillus plantarum CCM 7039 for malolactic fermentation to occur. The best results were achieved using 40 % sea buckthorn juice. Practical application of the results points to the possibility of preparing a fermented fruit beverage and a dairy product containing sea buckthorn juice. The results of this work extend the current options of sea buckthorn juice processing increasing thus the consumption of healthy juice.
{"title":"Influence of sea buckthorn juice addition on the growth of microbial food cultures","authors":"Svetlana Schubertová, Zuzana Burčová, M. Greifová, Marianna Potočňáková, Lívia Janotková, František Kreps","doi":"10.2478/acs-2021-0004","DOIUrl":"https://doi.org/10.2478/acs-2021-0004","url":null,"abstract":"Abstract The aim of the article was to investigate the effect of sea buckthorn juice addition on the growth of microbial cultures in growth medium and juice mixtures. Pure sea buckthorn juice was found to inhibit the growth of all 11 monitored microbial cultures. Lactobacillus plantarum CCM 7039, Lactobacillus plantarum K816, Lactobacillus brevis CCM 1815 and, to a lesser extent, the probiotic strain Lactobacillus rhamnosus GG, grew in a growth medium containing a 25 % addition of sea buckthorn juice. Lactobacillus plantarum K816 and Lactobacillus brevis CCM 1815 grew better in this mixture than in pure growth medium. Moreover, we focused on finding a suitable ratio of sea buckthorn and apple juice for Lactobacillus plantarum CCM 7039, leading to malolactic fermentation, which results in an increase in the pH value and an improvement in the sensory properties of juices. The intention was to incorporate the highest possible addition of sea buckthorn juice while maintaining the viability of Lactobacillus plantarum CCM 7039 for malolactic fermentation to occur. The best results were achieved using 40 % sea buckthorn juice. Practical application of the results points to the possibility of preparing a fermented fruit beverage and a dairy product containing sea buckthorn juice. The results of this work extend the current options of sea buckthorn juice processing increasing thus the consumption of healthy juice.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46106816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The main topic of this study is to determine the effect of selected antibiotics on the respirometric activity of sewage sludge microorganisms. Within the practical part of the work, several respirometric measurements were performed with activated sludge from a wastewater treatment plant, while the influence of three selected antibiotics — sulfamethoxazole, sulfapyridine, and ciprofloxacin, on sludge activity was monitored. The aim of the work was to point out the inhibitory effect of all monitored compounds on sludge activity and to quantify the inhibitory effect. For sulfamethoxazole (in the concentration range of 0.142—1.42 mg·L−1), the determined inhibition was in the range of 9.67—27.7 %, depending on the concentration of the test substance and the type of respirometric measurements. For sulfapyridine, inhibition values ranged from 1.13 % to 31.9 % for the concentration range from 0.134 to 1.34 mg·L−1. Ciprofloxacin inhibited the activity of activated sludge microorganisms in the range of 4.55 % to 28.8 % (at CPX concentrations from 0.104 to 1.04 mg·L−1).
{"title":"Influence of selected antibiotics on respirometric activity of activated sludge","authors":"Dóra Varjúová, Petra Szabová, I. Bodík","doi":"10.2478/acs-2021-0011","DOIUrl":"https://doi.org/10.2478/acs-2021-0011","url":null,"abstract":"Abstract The main topic of this study is to determine the effect of selected antibiotics on the respirometric activity of sewage sludge microorganisms. Within the practical part of the work, several respirometric measurements were performed with activated sludge from a wastewater treatment plant, while the influence of three selected antibiotics — sulfamethoxazole, sulfapyridine, and ciprofloxacin, on sludge activity was monitored. The aim of the work was to point out the inhibitory effect of all monitored compounds on sludge activity and to quantify the inhibitory effect. For sulfamethoxazole (in the concentration range of 0.142—1.42 mg·L−1), the determined inhibition was in the range of 9.67—27.7 %, depending on the concentration of the test substance and the type of respirometric measurements. For sulfapyridine, inhibition values ranged from 1.13 % to 31.9 % for the concentration range from 0.134 to 1.34 mg·L−1. Ciprofloxacin inhibited the activity of activated sludge microorganisms in the range of 4.55 % to 28.8 % (at CPX concentrations from 0.104 to 1.04 mg·L−1).","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47009610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Fašková, Daniela Pavúková, E. Mališová, L. Štibrányi, J. Híveš
Abstract Novel technologies for organic pollutants degradation have been studied to cope with extensive water pollution. In this work, the use of ultraviolet degradation and potassium ferrate as possible oxidation tools for toluene, a widely used industrial chemical, degradation is proposed. In the experiment with ultraviolet irradiation, a low-pressure mercury lamp was used to generate a single line electromagnetic radiation with the wavelength of 254 nm. Maximal degradation efficiency achieved after 55 minutes of irradiation was 67.1 %. In the experiments with potassium ferrate, the highest degradation efficiency was 71.2 % at the concentration of 10 mg/L of ferrate (VI) anion.
{"title":"Toluene oxidation: UV irradiation vs. ferrates","authors":"L. Fašková, Daniela Pavúková, E. Mališová, L. Štibrányi, J. Híveš","doi":"10.2478/acs-2020-0018","DOIUrl":"https://doi.org/10.2478/acs-2020-0018","url":null,"abstract":"Abstract Novel technologies for organic pollutants degradation have been studied to cope with extensive water pollution. In this work, the use of ultraviolet degradation and potassium ferrate as possible oxidation tools for toluene, a widely used industrial chemical, degradation is proposed. In the experiment with ultraviolet irradiation, a low-pressure mercury lamp was used to generate a single line electromagnetic radiation with the wavelength of 254 nm. Maximal degradation efficiency achieved after 55 minutes of irradiation was 67.1 %. In the experiments with potassium ferrate, the highest degradation efficiency was 71.2 % at the concentration of 10 mg/L of ferrate (VI) anion.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44423568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Elevated cholesterol intake can induce the development of cardiovascular diseases in man, especially with long term animal origin foods consumption. Therefore, this work deals with the possibility of cholesterol content decrease in milk applying β-cyclodextrin crosslinked with tartaric acid (βCDcTA) as a removal agent. Evaluation of statistic data on food consumption in the Slovak Republic in 2018 aimed at total cholesterol daily intake and effects of “milky” cholesterol content decrease on total cholesterol balance. During the experiments, various amounts of βCDcTA addition to milk were studied resulting in optimal 5 % addition resulting in the cholesterol content decrease by 85.4 % in comparison to original cholesterol content. For monitoring purposes, an HPLC method analysing cholesterol content in saponified milk was employed. The food consumption data analysis showed that total per capita daily cholesterol intake was 369.8 mg, from which 86 mg was assigned to the cholesterol contained in milk and dairy products while the application of cholesterol removal procedure could decrease the total per capita daily cholesterol intake to 296.3 mg (“milky” cholesterol amount equal to 12.6 mg), which in below the recommended value of 300 mg daily intake still valid in the Slovak Republic. This approach might prove as a meaningful step to weaken health problems associated with high long term intake of cholesterol contained in foods of animal origin.
{"title":"Decrease of cholesterol content in milk by sorption onto β-cyclodextrin crosslinked with tartaric acid; considerations and implications","authors":"M. Kukula, L. Kolarič, P. Šimko","doi":"10.2478/acs-2020-0024","DOIUrl":"https://doi.org/10.2478/acs-2020-0024","url":null,"abstract":"Abstract Elevated cholesterol intake can induce the development of cardiovascular diseases in man, especially with long term animal origin foods consumption. Therefore, this work deals with the possibility of cholesterol content decrease in milk applying β-cyclodextrin crosslinked with tartaric acid (βCDcTA) as a removal agent. Evaluation of statistic data on food consumption in the Slovak Republic in 2018 aimed at total cholesterol daily intake and effects of “milky” cholesterol content decrease on total cholesterol balance. During the experiments, various amounts of βCDcTA addition to milk were studied resulting in optimal 5 % addition resulting in the cholesterol content decrease by 85.4 % in comparison to original cholesterol content. For monitoring purposes, an HPLC method analysing cholesterol content in saponified milk was employed. The food consumption data analysis showed that total per capita daily cholesterol intake was 369.8 mg, from which 86 mg was assigned to the cholesterol contained in milk and dairy products while the application of cholesterol removal procedure could decrease the total per capita daily cholesterol intake to 296.3 mg (“milky” cholesterol amount equal to 12.6 mg), which in below the recommended value of 300 mg daily intake still valid in the Slovak Republic. This approach might prove as a meaningful step to weaken health problems associated with high long term intake of cholesterol contained in foods of animal origin.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42618790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This work aimed to determine the effect of packing density on the sublimation rate in a laboratory freeze dryer. Total amount of sublimed water was determined by gravimetric method while a total of seven experiments were performed under the same conditions (pressure, temperature, and drying time), at different configuration of the vials. The experiments confirmed that the higher the packing density, the lower the drying rate, and vice versa, the lower the packing density, the higher the drying rate. The effect of vials packing density was confirmed by experiments using a plastic rack, while the vials were separated and thus the packing density was lower. In this case, the drying rate was more homogeneous, which contributes to the higher quality of the final product.
{"title":"Impact of packing density on primary drying rate","authors":"Anna Matejčíková, P. Rajniak","doi":"10.2478/acs-2020-0021","DOIUrl":"https://doi.org/10.2478/acs-2020-0021","url":null,"abstract":"Abstract This work aimed to determine the effect of packing density on the sublimation rate in a laboratory freeze dryer. Total amount of sublimed water was determined by gravimetric method while a total of seven experiments were performed under the same conditions (pressure, temperature, and drying time), at different configuration of the vials. The experiments confirmed that the higher the packing density, the lower the drying rate, and vice versa, the lower the packing density, the higher the drying rate. The effect of vials packing density was confirmed by experiments using a plastic rack, while the vials were separated and thus the packing density was lower. In this case, the drying rate was more homogeneous, which contributes to the higher quality of the final product.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47381888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Cagardová, J. Truksa, M. Michalík, Jan Richtár, J. Krajcovic, M. Weiter, Vladimír Lukes
Abstract A systematic study of (7,8-dimethylated) alloxazine, isoalloxazine, and their derivatives with substituted N(1) and N(10) positions was conducted using the density functional theory. The main aim of this work was the direct investigation of substituent effect on the molecular structure. Furthermore, HOMED aromaticity indices were calculated to describe the scope of the geometry changes. Frontier molecular orbitals of reference alloxazine, isoalloxazine and lumichrome derivatives were discussed by means of changes in their shape and energy levels. Photophysical properties were analyzed by determination of optical transition energies using the TD-DFT method. Obtained results were compared with previously published experimental data.
{"title":"Theoretical modeling of optical spectra of N(1) and N(10) substituted lumichrome derivatives","authors":"D. Cagardová, J. Truksa, M. Michalík, Jan Richtár, J. Krajcovic, M. Weiter, Vladimír Lukes","doi":"10.2478/acs-2020-0017","DOIUrl":"https://doi.org/10.2478/acs-2020-0017","url":null,"abstract":"Abstract A systematic study of (7,8-dimethylated) alloxazine, isoalloxazine, and their derivatives with substituted N(1) and N(10) positions was conducted using the density functional theory. The main aim of this work was the direct investigation of substituent effect on the molecular structure. Furthermore, HOMED aromaticity indices were calculated to describe the scope of the geometry changes. Frontier molecular orbitals of reference alloxazine, isoalloxazine and lumichrome derivatives were discussed by means of changes in their shape and energy levels. Photophysical properties were analyzed by determination of optical transition energies using the TD-DFT method. Obtained results were compared with previously published experimental data.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49520095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Medveďová, Stanislava Kecskésová, Anna Krivjanská, M. Vojs, M. Marton, J. Filip, Miroslav Fehér, T. Mackuľak
Abstract Increasing concentration of antibiotics in environment and their subinhibitory concentrations in wastewater may result in increased antibiotic resistance of present bacteria. Therefore, this study was aimed to analyze the efficiency of coagulase-positive staphylococci and Staphylococcus aureus inhibition in wastewater by electrochemical methods and addition of ferrates. Advanced electrochemical oxidation by boron doped diamond electrodes in anode; cathode and anode-cathode connection were used for wastewater disinfection. Results showed that the most effective connection was the anodic one, as complete inhibition of coagulase-positive staphylococci as well as of S. aureus was observed after 40 min. Energy consumption was 3.69 kWh/m3 for effluent wastewater disinfection. The second studied method of wastewater disinfection was the application of powdered ferrates. Addition of 100 mg of ferrates resulted in the inhibition of 84—96 % of coagulase-positive staphylococci and 97—99 % of S. aureus in influent water, while the inhibition of coagulase-positive staphylococci and S. aureus was 61—83 % and 83—86 %, respectively, in effluent wastewater.
{"title":"Inhibition of staphylococci and S. aureus in wastewater by ferrates and electrochemical methods","authors":"A. Medveďová, Stanislava Kecskésová, Anna Krivjanská, M. Vojs, M. Marton, J. Filip, Miroslav Fehér, T. Mackuľak","doi":"10.2478/acs-2020-0023","DOIUrl":"https://doi.org/10.2478/acs-2020-0023","url":null,"abstract":"Abstract Increasing concentration of antibiotics in environment and their subinhibitory concentrations in wastewater may result in increased antibiotic resistance of present bacteria. Therefore, this study was aimed to analyze the efficiency of coagulase-positive staphylococci and Staphylococcus aureus inhibition in wastewater by electrochemical methods and addition of ferrates. Advanced electrochemical oxidation by boron doped diamond electrodes in anode; cathode and anode-cathode connection were used for wastewater disinfection. Results showed that the most effective connection was the anodic one, as complete inhibition of coagulase-positive staphylococci as well as of S. aureus was observed after 40 min. Energy consumption was 3.69 kWh/m3 for effluent wastewater disinfection. The second studied method of wastewater disinfection was the application of powdered ferrates. Addition of 100 mg of ferrates resulted in the inhibition of 84—96 % of coagulase-positive staphylococci and 97—99 % of S. aureus in influent water, while the inhibition of coagulase-positive staphylococci and S. aureus was 61—83 % and 83—86 %, respectively, in effluent wastewater.","PeriodicalId":7088,"journal":{"name":"Acta Chimica Slovaca","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49636607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}