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1.
Appl Biochem Biotechnol ; 196(1): 314-331, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37126113

ABSTRACT

In this study, the second-life application of Saccharomyces cerevisiae obtained from brewery wastewater was evaluated in the biosorption of Se(IV) (Na2SeO3) sorbate in residue generated from a fine chemical industry. Biosorption experiments were carried out with different Se(IV) concentrations (A = 7.5 to 30.0 mg L-1 dissolved in deionized water or industrial effluent) and different biosorbent concentrations (B = 2.0 to 52.5 g L-1, dry mass). Inactive microbial biomass was evaluated in a wet and dehydrated state. The highest selenium removal efficiency (biosorption efficiency-R = 97.5%) was achieved with the same concentrations of sorbate in deionized water, using 24.0 g L-1 of wet cells. In contrast, the industrial effluent treatment showed lower biosorption efficiency (R = 83.3%) due to a large amount of other salts in the medium, mainly sulphur. Overall, the use of smaller amounts of biosorbent had a biosorption capacity of approximately five times greater than when 24.0 g L-1 in industrial effluent treatment was used. However, as reducing the concentration of the contaminant contained in the wastewater is the primary goal of this study, a more significant amount of biosorbent is recommended.


Subject(s)
Selenium , Water Pollutants, Chemical , Saccharomyces cerevisiae , Wastewater , Adsorption , Hydrogen-Ion Concentration , Biomass , Water , Water Pollutants, Chemical/analysis , Kinetics
2.
MethodsX ; 10: 102128, 2023.
Article in English | MEDLINE | ID: mdl-36974326

ABSTRACT

A primary pollution source by pharmaceuticals is hospital wastewater (HWW). Herein, the methods involved in the action of a biological system (BS, aerobic activated sludge) or a sonochemical treatment (US, 375 kHz and 30.8 W), for degrading four relevant pharmaceuticals (azithromycin, ciprofloxacin, paracetamol, and valsartan) in HWW, are shown. Before treatment of HWW, the correct performance of BS was assessed using glucose as a reference substance, monitoring oxygen consumption, and organic carbon removal. Meanwhile, for US, a preliminary test using ciprofloxacin in distilled water was carried out. The determination of risk quotients (RQ) and theoretical analyses about reactive moieties on these target substances are also presented. For both, the degradation of the pharmaceuticals and the calculation of RQ, analyses were performed by LC-MS/MS. The BS action decreased the concentration of paracetamol and valsartan by ∼96 and 86%, respectively. However, a poor action on azithromycin (2% removal) was found, whereas ciprofloxacin concentration increased ∼20%; leading to an RQ value of 1.61 (high risk) for the pharmaceuticals mixture. The analyses using a biodegradation pathway predictor (EAWAG-BDD methodology) revealed that the amide group on paracetamol and alkyl moieties on valsartan could experience aerobic biotransformations. In turn, US action decreased the concentration of the four pharmaceuticals (removals > 60% for azithromycin, ciprofloxacin, and paracetamol), diminishing the environmental risk (RQ: 0.51 for the target pharmaceuticals mixture). Atomic charge analyses (based on the electronegativity equalization method) were performed, showing that the amino-sugar on azithromycin; piperazyl ring, and double bond close to the two carbonyls on ciprofloxacin, acetamide group on paracetamol, and the alkyl moieties bonded to the amide group of valsartan are the most susceptible moieties to attacks by sonogenerated radicals. The LC-MS/MS analytical methodology, RQ calculations, and theoretical analyses allowed for determining the degrading performance of BS and US toward the target pollutants in HWW.•Biological and sonochemical treatments as useful methods for degrading 4 representative pharmaceuticals are presented.•Sonochemical treatment had higher degrading action than the biological one on the target pharmaceuticals.•Methodologies for risk environmental calculation and identification of moieties on the pharmaceuticals susceptible to radical attacks are shown.

3.
Toxics ; 10(5)2022 Apr 22.
Article in English | MEDLINE | ID: mdl-35622623

ABSTRACT

Insulating oil contaminated with polychlorinated biphenyls (PCBs) is an environmentally important pollutant. This research focused on the establishment of the optimum conditions under which photocatalytic oxidation can be used together with biotreatment using the Nostoc sp. microorganism to degrade PCBs present in used dielectric oils. Among the optimal conditions studied were PCB concentration, initial pH, and titanium dioxide (TiO2) concentration for the photocatalytic step, and PCB concentration and photoperiod for the biotreatment step. The results indicate that the optimal conditions necessary for photocatalytic degradation were a pH of 6.10, 113 mg/L TiO2, and 765 mg/L PCBs, achieving close to 90% removal. For the biotreatment step, the results showed that PCBs progressively inhibited the microbiological growth, with the lowest cellular growth observed in the medium with the highest PCB concentration.

4.
Eng. sanit. ambient ; Eng. sanit. ambient;22(5): 1027-1035, set.-out. 2017. tab, graf
Article in Portuguese | LILACS | ID: biblio-891576

ABSTRACT

RESUMO Os processos industriais de produção têxtil têm como característica o uso de grandes volumes de água durante as etapas de lavagem e tingimento dos tecidos, resultando em efluentes com enorme diversidade e complexidade química. A presença de corantes dissolvidos é bastante visível e problemática, considerando sua recalcitrância e cinética de degradação lenta. Neste trabalho, o fungo Lasiodiplodia theobromae MMPI foi avaliado quanto à capacidade de descoloração de efluente industrial têxtil. Os ensaios foram conduzidos em biorreator de bancada (5 L) com tempo de incubação de 192 horas. A eficiência de descoloração variou de 19,52% (24 h) a 91,26% (168 h) e a produção de biomassa micelial variou de 1,23 g.L-1 (24 h) a 7,60 g.L-1 (168 h). Produção de exopolissacarídeo (EPS) também foi observada, com quantidades variando de 2,84 g L-1 em 24 h a 4,28 g.L-1 em 48 h. A caracterização do efluente industrial indicou valores de alguns parâmetros de controle fora dos padrões de lançamento exigidos pela legislação brasileira, com elevada demanda química de oxigênio (DQO) (659 mg.L-1) e demanda bioquímica de oxigênio (DBO5) (328 mg.L-1). A análise de toxicidade utilizando o microcrustáceo Artemia salina demonstrou que a concentração de efluente bruto que causou a mortalidade de 50% dos organismos (CL50) foi de aproximadamente 14,72% (v/v) e ao final do tratamento foi de 4,98% (v/v). Embora o fungo não tenha sido hábil na detoxificação biológica do efluente, ele apresentou resultados promissores quanto à capacidade de remoção de cor, demonstrando potencial de uso em processos auxiliares de tratamento de efluente industrial têxtil visando descoloração.


ABSTRACT The industrial processes of textile production are characterized by the use of large volumes of water during the washing steps and fabric dyeing, resulting in effluent with enormous diversity and chemical complexity. The presence of dissolved dyes is quite noticeable and problematic, considering their recalcitrance and slow degradation kinetic. In this work, the Lasiodiplodia theobromae MMPI fungus was evaluated for their ability to removing color from effluent. The assays were performed in a bench-scale bioreactor (5 L) with an incubation time of 192 hours. The decoloring efficiency ranged from 19.52% on 24h to 91,26% on 168 h and the mycelial biomass production ranged from 1.23 g.L-1 (24 h) to 7.60 g.L-1 (168 h). Production of exopolysaccharide (EPS) also was observed, with amounts ranged from 2.84 g.L-1 (24 h) to 4.28 g.L-1 (48 h). The characterization of the effluent showed some values of control parameters outside the discharge standards required by Brazilian law, with high Chemical Oxygen Demand (COD) (659 mg.L-1) and Biochemical Oxygen Demand (BOD5) (328 mg.L-1). The toxicity analysis using the microcrustacean Artemia salina, showed that the raw effluent concentration that caused 50% mortality of organisms (LC50) was approximately 14.72% (v/v) and at the end of treatment was 4.98% (v/v). Although the fungus was not efficient in biological detoxification of the effluent, it showed promising results for its color removal capacity, demonstrating potential for use in auxiliary treatment processes of textile effluents for the color removal.

5.
Braz. J. Microbiol. ; 43(4): 1523-1535, Oct.-Dec. 2012. graf, tab
Article in English | VETINDEX | ID: vti-2124

ABSTRACT

This study was designed to evaluate selected chemical and microbiological treatments for the conversion of certain local agro-industrial wastes (rice straw, corn stalks, sawdust, sugar beet waste and sugarcane bagasse) to ethanol. The chemical composition of these feedstocks was determined. Conversion of wastes to free sugars by acid hydrolysis varied from one treatment to another. In single-stage dilute acid hydrolysis, increasing acid concentration from 1 % (v/v) to 5 % (v/v) decreased the conversion percentage of almost all treated agro-industrial wastes. Lower conversion percentages for some treatments were obtained when increasing the residence time from 90 to 120min. The two-stage dilute acid hydrolysis by phosphoric acid (1.0 % v/v) followed by sulphuric acid (1.0 % v/v) resulted in the highest conversion percentage (41.3 % w/w) on treated sugar beet waste. This treatment when neutralized, amended with some nutrients and inoculated with baker's yeast, achieved the highest ethanol concentration (1.0 % v/v). Formation of furfural and hydroxymethylfurfural (HMF) were functions of type of acid hydrolysis, acid concentration, residence time and feedstock type. The highest bioconversion of 5 % wastes (37.8 % w/w) was recorded on sugar beet waste by Trichoderma viride EMCC 107. This treatment when followed by baker's yeast fermentation, 0.41 % (v/v) ethanol and 8.2 % (v/w) conversion coefficient were obtained.(AU)


Subject(s)
Ethanol/analysis , /methods , Hydrolysis , Carbohydrates/biosynthesis , Fungi/classification
6.
Braz. j. microbiol ; Braz. j. microbiol;43(4): 1523-1535, Oct.-Dec. 2012. graf, tab
Article in English | LILACS | ID: lil-665840

ABSTRACT

This study was designed to evaluate selected chemical and microbiological treatments for the conversion of certain local agro-industrial wastes (rice straw, corn stalks, sawdust, sugar beet waste and sugarcane bagasse) to ethanol. The chemical composition of these feedstocks was determined. Conversion of wastes to free sugars by acid hydrolysis varied from one treatment to another. In single-stage dilute acid hydrolysis, increasing acid concentration from 1 % (v/v) to 5 % (v/v) decreased the conversion percentage of almost all treated agro-industrial wastes. Lower conversion percentages for some treatments were obtained when increasing the residence time from 90 to 120min. The two-stage dilute acid hydrolysis by phosphoric acid (1.0 % v/v) followed by sulphuric acid (1.0 % v/v) resulted in the highest conversion percentage (41.3 % w/w) on treated sugar beet waste. This treatment when neutralized, amended with some nutrients and inoculated with baker's yeast, achieved the highest ethanol concentration (1.0 % v/v). Formation of furfural and hydroxymethylfurfural (HMF) were functions of type of acid hydrolysis, acid concentration, residence time and feedstock type. The highest bioconversion of 5 % wastes (37.8 % w/w) was recorded on sugar beet waste by Trichoderma viride EMCC 107. This treatment when followed by baker's yeast fermentation, 0.41 % (v/v) ethanol and 8.2 % (v/w) conversion coefficient were obtained.


Subject(s)
Agribusiness/analysis , Ethanol/analysis , Fermentation , Trichoderma/enzymology , Trichoderma/isolation & purification , Food Samples , Hydrolysis , Methods , Waste Products
7.
Braz J Microbiol ; 43(4): 1523-35, 2012 Oct.
Article in English | MEDLINE | ID: mdl-24031984

ABSTRACT

This study was designed to evaluate selected chemical and microbiological treatments for the conversion of certain local agro-industrial wastes (rice straw, corn stalks, sawdust, sugar beet waste and sugarcane bagasse) to ethanol. The chemical composition of these feedstocks was determined. Conversion of wastes to free sugars by acid hydrolysis varied from one treatment to another. In single-stage dilute acid hydrolysis, increasing acid concentration from 1 % (v/v) to 5 % (v/v) decreased the conversion percentage of almost all treated agro-industrial wastes. Lower conversion percentages for some treatments were obtained when increasing the residence time from 90 to 120 min. The two-stage dilute acid hydrolysis by phosphoric acid (1.0 % v/v) followed by sulphuric acid (1.0 % v/v) resulted in the highest conversion percentage (41.3 % w/w) on treated sugar beet waste. This treatment when neutralized, amended with some nutrients and inoculated with baker's yeast, achieved the highest ethanol concentration (1.0 % v/v). Formation of furfural and hydroxymethylfurfural (HMF) were functions of type of acid hydrolysis, acid concentration, residence time and feedstock type. The highest bioconversion of 5 % wastes (37.8 % w/w) was recorded on sugar beet waste by Trichoderma viride EMCC 107. This treatment when followed by baker's yeast fermentation, 0.41 % (v/v) ethanol and 8.2 % (v/w) conversion coefficient were obtained.

8.
Article in English | VETINDEX | ID: vti-443788

ABSTRACT

Poly (caprolactone) is a famous biodegradable polymer and miscible with PVC, a commercial synthetic polymer, thermal susceptible and non-biodegradable. This blend is important concerning its mechanical properties and biodegradability. In this work, we testified the biomodification of blend films of PVC/PCL by UV-Vis. spectroscopy. The results show us that there is an interaction between the PVC/PCL film and the microrganisms.


Poli épsilon-caprolactona é um importante polímero biodegradável e miscível com o PVC, um polímero sintético industrial, termo susceptível e não biodegradável. A blenda PVC/PCL é importante em propriedades mecânicas e biodegradabilidade. Neste trabalho, há indicações que há interação dos microrganismos com a superfície polimérica e esta causa mudanças estruturais na blenda PVC/PCL.

9.
Braz. j. microbiol ; Braz. j. microbiol;342003.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469453

ABSTRACT

Poly (caprolactone) is a famous biodegradable polymer and miscible with PVC, a commercial synthetic polymer, thermal susceptible and non-biodegradable. This blend is important concerning its mechanical properties and biodegradability. In this work, we testified the biomodification of blend films of PVC/PCL by UV-Vis. spectroscopy. The results show us that there is an interaction between the PVC/PCL film and the microrganisms.


Poli épsilon-caprolactona é um importante polímero biodegradável e miscível com o PVC, um polímero sintético industrial, termo susceptível e não biodegradável. A blenda PVC/PCL é importante em propriedades mecânicas e biodegradabilidade. Neste trabalho, há indicações que há interação dos microrganismos com a superfície polimérica e esta causa mudanças estruturais na blenda PVC/PCL.

10.
Braz. j. microbiol ; Braz. j. microbiol;342003.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469500

ABSTRACT

Poly (caprolactone) is a famous biodegradable polymer and miscible with PVC, a commercial synthetic polymer, thermal susceptible and non-biodegradable. This blend is important concerning its mechanical properties and biodegradability. In this work, we testified the biomodification of blend films of PVC/PCL by UV-Vis. spectroscopy. The results show us that there is an interaction between the PVC/PCL film and the microrganisms.


Poli épsilon-caprolactona é um importante polímero biodegradável e miscível com o PVC, um polímero sintético industrial, termo susceptível e não biodegradável. A blenda PVC/PCL é importante em propriedades mecânicas e biodegradabilidade. Neste trabalho, há indicações que há interação dos microrganismos com a superfície polimérica e esta causa mudanças estruturais na blenda PVC/PCL.

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