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This work is focused on the valorization of brewer’s spent grains (BSG) into volatile fatty acids (VFA) through acidogenic fermentation. VFAs are building blocks for several applications, such as bioplastics’ production. Using acid hydrolysis as pre-treatment, several batch assays were performed and the impact of organic load (OL) and pH on VFA production from BSG hydrolysate was assessed. Regardless of the condition, the produced acids were mainly butyric and acetic acids followed by propionic acid. The OL had a direct impact on the total organic acid concentration with higher concentrations at the highest OL (40 gCOD L−1). pH affected the concentration of individual organic acid, with the highest fermentation products (FP) diversity attained at pH 5.0 and OL of 40 gCOD L−1. To assess the potential application of organic acids for biopolymers (such as polyhydroxyalkanoates) production, the content in hydroxybutyrate (HB) and hydroxyvalerate (HV) monomers was estimated from the respective precursors produced at each pH and OL. The content in HV precursors increased with pH, with a maximum at pH 6.0 (ca. 16% C-mol basis). The acidogenic fermentation of BSG hydrolysate was also assessed in continuous operation, using an expanded granular sludge bed reactor (EGSB). It was shown that the BSG hydrolysate was successfully converted to VFAs without pH control, achieving higher productivities than in the batch operation mode.
Eliana Guarda; Ana Oliveira; Sílvia Antunes; Filomena Freitas; Paula Castro; Anouk Duque; Maria Reis. A Two-Stage Process for Conversion of Brewer’s Spent Grain into Volatile Fatty Acids through Acidogenic Fermentation. Applied Sciences 2021, 11, 3222 .
AMA StyleEliana Guarda, Ana Oliveira, Sílvia Antunes, Filomena Freitas, Paula Castro, Anouk Duque, Maria Reis. A Two-Stage Process for Conversion of Brewer’s Spent Grain into Volatile Fatty Acids through Acidogenic Fermentation. Applied Sciences. 2021; 11 (7):3222.
Chicago/Turabian StyleEliana Guarda; Ana Oliveira; Sílvia Antunes; Filomena Freitas; Paula Castro; Anouk Duque; Maria Reis. 2021. "A Two-Stage Process for Conversion of Brewer’s Spent Grain into Volatile Fatty Acids through Acidogenic Fermentation." Applied Sciences 11, no. 7: 3222.
The food industrial sector generates large amounts of waste, which are often used for animal feed, for agriculture or landfilled. However, these wastes have a very reach composition in carbon and other compounds, which make them very attractive for valorization through biotechnological processes. Added value compounds, such as volatile fatty acids (VFAs), can be produced by anaerobic fermentation using pure cultures or mixed microbial cultures and food waste as carbon source. Research on valuable applications for VFAs, such as polyhydroxyalkanoates, bioenergy or biological nutrient removal, towards a circular economy is emerging. This enhances the sustainability and the economic value of food waste. This chapter reviews the various types of food waste used for VFAs production using mixed microbial cultures, the anaerobic processes, involved and the main applications for the produced VFAs. The main parameters affecting VFAs production are also discussed.
Mónica Carvalheira; Anouk F. Duque. From Food Waste to Volatile Fatty Acids towards a Circular Economy. Fermentation - Processes, Benefits and Risks [Working Title] 2021, 1 .
AMA StyleMónica Carvalheira, Anouk F. Duque. From Food Waste to Volatile Fatty Acids towards a Circular Economy. Fermentation - Processes, Benefits and Risks [Working Title]. 2021; ():1.
Chicago/Turabian StyleMónica Carvalheira; Anouk F. Duque. 2021. "From Food Waste to Volatile Fatty Acids towards a Circular Economy." Fermentation - Processes, Benefits and Risks [Working Title] , no. : 1.
This work is focused on production of volatile fatty acids (VFA) through anaerobic digestion (AD) using raw (without pre-treatment) brewers’ spent grain (BSG) as feedstock. VFAs are by-products from AD of organic wastes with wide potential industrial application in bioplastic production. A long term fed batch stirred-tank reactor was operated and the impact of three hydraulic retention times (HRT) and two organic loading rates (OLR) on VFA production was assessed. Results showed clearly that AD of raw BSG is possible without a pre-treatment step. The maximum volumetric VFA productivity of 91.3 ± 9.1 mgCODL−1 h−1 and VFA concentration of 24.9 ± 2.6 g L−1 were obtained for 16 days of HRT and 16 gTSinL−1d−1 of OLR. This is the highest value of VFA concentration so far reported for BSG. Propionic, acetic and butyric acids were the main VFAs produced. Community identification by FISH and its correlation with process parameters was performed by principal component analysis.
Margarida Ribau Teixeira; Eliana Guarda; Elisabete B. Freitas; Claudia F. Galinha; Anouk F. Duque; Maria A.M. Reis. Valorization of raw brewers’ spent grain through the production of volatile fatty acids. New Biotechnology 2020, 57, 4 -10.
AMA StyleMargarida Ribau Teixeira, Eliana Guarda, Elisabete B. Freitas, Claudia F. Galinha, Anouk F. Duque, Maria A.M. Reis. Valorization of raw brewers’ spent grain through the production of volatile fatty acids. New Biotechnology. 2020; 57 ():4-10.
Chicago/Turabian StyleMargarida Ribau Teixeira; Eliana Guarda; Elisabete B. Freitas; Claudia F. Galinha; Anouk F. Duque; Maria A.M. Reis. 2020. "Valorization of raw brewers’ spent grain through the production of volatile fatty acids." New Biotechnology 57, no. : 4-10.
Polyhydroxyalkanoates (PHA) are biopolymers that can be produced by mixed microbial cultures using wastes or industrial by-products, which represent an economical and environmental advantage over pure culture processes. The use of alternate feedstocks enables using seasonal by-products, providing that the process is resilient to transient conditions. The mixed microbial communities of a 3-stage PHA producing system fed initially with molasses and then cheese whey were investigated through amplicon sequencing of the 16S rRNA gene. The transition in feedstock resulted in an adaptation of the acidogenic community, where Actinobacteria dominated with sugarcane molasses (up to 93% of the operational taxonomic units) and Firmicutes, with cheese whey (up to 97%). The resulting fermentation products profile also changed, with a higher fraction of HV precursors obtained with molasses than cheese whey (7.1±0.5 and 1.7±0.7 gCOD/L, respectively). As for the PHA storing culture, the genera Azoarcus, Thauera and Paracoccus were enriched with fermented molasses (average 89% of Bacteria). Later, fermented cheese whey fostered a higher diversity, including some less characterised PHA-storers such as the genera Paenibacillus and Lysinibacillus. Although the microbial community structure was significantly affected by the feedstock shift, the acidogenic and PHA storing performance of the 3-stage system was very similar once a pseudo steady state was attained, showing that a reliable level of functional redundancy was attained in both mixed cultures.
Gilda Carvalho; Inês Pedras; Søren Michael Karst; Catarina Oliveira; Anouk F. Duque; Per H. Nielsen; Maria A.M. Reis. Functional redundancy ensures performance robustness in 3-stage PHA-producing mixed cultures under variable feed operation. New Biotechnology 2018, 40, 207 -217.
AMA StyleGilda Carvalho, Inês Pedras, Søren Michael Karst, Catarina Oliveira, Anouk F. Duque, Per H. Nielsen, Maria A.M. Reis. Functional redundancy ensures performance robustness in 3-stage PHA-producing mixed cultures under variable feed operation. New Biotechnology. 2018; 40 ():207-217.
Chicago/Turabian StyleGilda Carvalho; Inês Pedras; Søren Michael Karst; Catarina Oliveira; Anouk F. Duque; Per H. Nielsen; Maria A.M. Reis. 2018. "Functional redundancy ensures performance robustness in 3-stage PHA-producing mixed cultures under variable feed operation." New Biotechnology 40, no. : 207-217.
Polyhydroxyalkanoates (PHA) are a sustainable alternative to conventional plastics that can be obtained from industrial wastes/by-products using mixed microbial cultures (MMC). MMC PHA production is commonly carried out in a 3-stage process of acidogenesis, PHA culture selection and accumulation. This research focused on the possibility of tailoring PHA by controlling the acidogenic reactor operating conditions, namely pH, using cheese whey as model feedstock. The objective was to investigate the impact that dynamically varying the acidogenic pH, when targeting different PHA monomer profiles, had on the performance and microbial community profile of the anaerobic reactor. To accomplish this, an anaerobic reactor was continuously operated under dynamic pH changes, ranging from pH 4 to 7, turning to pH 6 after each change of pH. At pH 6, lactate and acetate were the dominant products (41-48% gCOD basis and 22-44% gCOD basis, respectively). At low pH, lactate production was higher while at high pH acetate production was favoured. Despite the dynamic change of pH, the fermentation product composition at pH 6 was always similar, showing the resilience of the process, i.e. when the same pH value was imposed, the culture produced the same metabolic products independently of the history of changes occurring in the system. The different fermentation product fractions led to PHAs of different compositions. The microbial community, analysed by high throughput sequencing of bacterial 16 S rRNA gene fragments, was dominated by Lactobacillus, but varied markedly when subjected to the highest and lowest pH values of the tested range (4 and 7), with increase in the abundance of Lactococcus and a member of the Candidate Division TM7. Different bacterial profiles obtained at pH 6 during this dynamic operation were able to produce a consistent profile of fermentation products (and consequently a constant PHA composition), demonstrating the community’s functional redundancy.
Ana R. Gouveia; Elisabete B. Freitas; Claudia F. Galinha; Gilda Carvalho; Anouk F. Duque; Maria A.M. Reis. Dynamic change of pH in acidogenic fermentation of cheese whey towards polyhydroxyalkanoates production: Impact on performance and microbial population. New Biotechnology 2017, 37, 108 -116.
AMA StyleAna R. Gouveia, Elisabete B. Freitas, Claudia F. Galinha, Gilda Carvalho, Anouk F. Duque, Maria A.M. Reis. Dynamic change of pH in acidogenic fermentation of cheese whey towards polyhydroxyalkanoates production: Impact on performance and microbial population. New Biotechnology. 2017; 37 ():108-116.
Chicago/Turabian StyleAna R. Gouveia; Elisabete B. Freitas; Claudia F. Galinha; Gilda Carvalho; Anouk F. Duque; Maria A.M. Reis. 2017. "Dynamic change of pH in acidogenic fermentation of cheese whey towards polyhydroxyalkanoates production: Impact on performance and microbial population." New Biotechnology 37, no. : 108-116.
Aerobic Granular Sludge (AGS) has been successfully applied for carbon, nitrogen and phosphorous removal from wastewaters, in a single tank, reducing the space and energy requirements. This is especially beneficial for, often space restricted, industrial facilities. Moreover, AGS holds a promise for the toxic pollutants removal, due to its layered and compact structure and the bacteria embedding in a protective extracellular polymeric matrix. These outstanding features contribute to AGS tolerance to toxicity and stability. Strategies available to deal with toxic compounds, namely granulation with effluents containing toxics and bioaugmentation, are addressed here. Different applications for the toxics/micropollutants removal through biosorption and/or biodegradation are presented, illustrating the technology versatility. The anthropogenic substances effects on system performance and bacterial populations established within AGS are also addressed. Combination of contaminants removal to allow water discharge, and simultaneous valuable products recovery are presented as final remark.
Catarina L. Amorim; Irina Moreira; Anouk F. Duque; Mark C. M. Van Loosdrecht; Paula M. L. Castro. Aerobic Granular Sludge. Advances in Environmental Engineering and Green Technologies 2017, 231 -263.
AMA StyleCatarina L. Amorim, Irina Moreira, Anouk F. Duque, Mark C. M. Van Loosdrecht, Paula M. L. Castro. Aerobic Granular Sludge. Advances in Environmental Engineering and Green Technologies. 2017; ():231-263.
Chicago/Turabian StyleCatarina L. Amorim; Irina Moreira; Anouk F. Duque; Mark C. M. Van Loosdrecht; Paula M. L. Castro. 2017. "Aerobic Granular Sludge." Advances in Environmental Engineering and Green Technologies , no. : 231-263.
Anouk F. Duque; Paula M.L. Castro; Maria A.M. Reis. Treatment and valorization of celullosic fraction of brewery waste. New Biotechnology 2016, 33, S69 .
AMA StyleAnouk F. Duque, Paula M.L. Castro, Maria A.M. Reis. Treatment and valorization of celullosic fraction of brewery waste. New Biotechnology. 2016; 33 ():S69.
Chicago/Turabian StyleAnouk F. Duque; Paula M.L. Castro; Maria A.M. Reis. 2016. "Treatment and valorization of celullosic fraction of brewery waste." New Biotechnology 33, no. : S69.
Two polyhydroxy(butyrate-co-valerate) (PHBV) produced from mixed microbial cultures (MMC) fed with fermented cheese whey (CW) and recovered with different down streaming routes, were processed into filaments by plasticating extrusion. The thermorheological characteristics were improved when fermentation residues were recovered together with the MMC PHBV polymer. Thermogravimetric analysis of the extruded filaments showed that MMC PHBV with 11% residues was less degraded than pure PHBV after the thermomechanical processing. Infrared spectroscopy indicated that residues rich in OH groups were volatilized during extrusion, thereby originating filaments that were less degraded than those produced with purified MMC PHBV. Residues had no impact on the semi crystalline properties of the filaments, but were responsible for their depressed mechanical properties, significant color deterioration upon processing and narrowed the processing operating window of MMC PHBV.
Loic Hilliou; Paulo Teixeira; Diogo Machado; José A. Covas; Catarina S.S. Oliveira; Anouk Duque; Maria A. Reis. Effects of fermentation residues on the melt processability and thermomechanical degradation of PHBV produced from cheese whey using mixed microbial cultures. Polymer Degradation and Stability 2016, 128, 269 -277.
AMA StyleLoic Hilliou, Paulo Teixeira, Diogo Machado, José A. Covas, Catarina S.S. Oliveira, Anouk Duque, Maria A. Reis. Effects of fermentation residues on the melt processability and thermomechanical degradation of PHBV produced from cheese whey using mixed microbial cultures. Polymer Degradation and Stability. 2016; 128 ():269-277.
Chicago/Turabian StyleLoic Hilliou; Paulo Teixeira; Diogo Machado; José A. Covas; Catarina S.S. Oliveira; Anouk Duque; Maria A. Reis. 2016. "Effects of fermentation residues on the melt processability and thermomechanical degradation of PHBV produced from cheese whey using mixed microbial cultures." Polymer Degradation and Stability 128, no. : 269-277.
Aerobic granular sludge constitutes a novel technology for wastewater treatment. This study focused on the effect of 2-fluorophenol (2-FP) shock loadings on the microbial community diversity present in aerobic granules before and after inoculation with a bacterial strain able to degrade 2-FP, Rhodococcus sp. strain FP1. After bioaugmentation, apart from strain FP1, five culturable bacteria were isolated from the 2-FP degrading granules, belonging to the following genera: Serratia, Chryseobacterium, Xanthomonas, Pimelobacter and Rhodococcus. The latter two isolates are able to degrade 2-FP. Changes in the aerobic granules’ bacterial communities related to 2-FP shock loadings were examined using denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene pool. Numerical analysis of the DGGE profiles showed high diversity with an even distribution of species. Based on cluster analysis of the DGGE profiles, the bacterial communities present in the aerobic granules changes were related to the sampling time and the 2-FP concentration fed.
Anouk Duque; Vânia S. Bessa; Paula M.L. Castro. Characterization of the bacterial communities of aerobic granules in a 2-fluorophenol degrading process. Biotechnology Reports 2014, 5, 98 -104.
AMA StyleAnouk Duque, Vânia S. Bessa, Paula M.L. Castro. Characterization of the bacterial communities of aerobic granules in a 2-fluorophenol degrading process. Biotechnology Reports. 2014; 5 ():98-104.
Chicago/Turabian StyleAnouk Duque; Vânia S. Bessa; Paula M.L. Castro. 2014. "Characterization of the bacterial communities of aerobic granules in a 2-fluorophenol degrading process." Biotechnology Reports 5, no. : 98-104.
Polyhydroxyalkanoates (PHA) can be produced by mixed microbial cultures (MMC) using a three-stage process. An attractive feature of MMC for PHA production is the ability to use waste/surplus feedstocks. In this study, the effect of a feedstock shift, mimicking a seasonal feedstock scenario and/or as a strategy for controlling polymer composition, on a MMC PHA production process was assessed using cheese whey (CW) and sugar cane molasses (SCM) as model feedstocks. The acidogenic stage responded immediately to the feedstock shift by changing the fermented products profile, with acetate and butyrate being the main acids produced from CW, while for SCM propionate and valerate were the dominant products. The fermentation process was then quite stable during long term operation. The PHA culture selection stage also responded quickly to the fermented feestocks shift, generating a polymer whose composition was linearly dependent on the concentration of HV and HB precursors produced in the acidogenic stage. The selected culture reached a maximum PHA content of 56% and 65% with fermented SCM and CW, respectively. Mixing fermented CW and SCM, in equal volume proportions, demonstrated the possibility of using different fermented feedstocks for tailoring polymer composition.
Anouk Duque; Catarina Oliveira; Inês T.D. Carmo; Ana R. Gouveia; Filipa Pardelha; Ana Maria Ramos; Maria A.M. Reis. Response of a three-stage process for PHA production by mixed microbial cultures to feedstock shift: impact on polymer composition. New Biotechnology 2014, 31, 276 -288.
AMA StyleAnouk Duque, Catarina Oliveira, Inês T.D. Carmo, Ana R. Gouveia, Filipa Pardelha, Ana Maria Ramos, Maria A.M. Reis. Response of a three-stage process for PHA production by mixed microbial cultures to feedstock shift: impact on polymer composition. New Biotechnology. 2014; 31 (4):276-288.
Chicago/Turabian StyleAnouk Duque; Catarina Oliveira; Inês T.D. Carmo; Ana R. Gouveia; Filipa Pardelha; Ana Maria Ramos; Maria A.M. Reis. 2014. "Response of a three-stage process for PHA production by mixed microbial cultures to feedstock shift: impact on polymer composition." New Biotechnology 31, no. 4: 276-288.
One of the main factors affecting the performance of rotating biological contactors (RBC) is the biofilm characteristics. Therefore, a deep understanding of the microbial population dynamics and structure of the biofilm is mandatory if optimization of organic matter and nutrients removal is targeted. This study focused on the effects of organic shock loads of 2-fluorophenol (2-FP) on the microbial diversity present in an RBC biofilm. The RBC was seeded with activated sludge from a conventional wastewater treatment plant and was operated during 496 days. During the first 126 days, the RBC was subjected to intermittent 2-FP shocks of 25 mg l−1 and no degradation occurred. Therefore, the reactor was subsequently augmented with a 2-FP-degrading strain (FP1). Afterwards, the RBC had a stable performance when subjected to 2-FP shocks up to 50 mg l−1 and to a starvation period, as indicated by removal of the compound. Denaturing gradient gel electrophoresis (DGGE) revealed large shifts in microbial communities present in the first and fifth stages, although no clear relation between the sample collection time and spatial factor was found. Phylogenetic affiliation of some predominant members was assessed by direct sequencing of correspondent DGGE bands. Affiliations to α-, β- and δ-Proteobacteria were found. Several bacterial strains isolated from the reactor showed capacity for 2-FP degradation. Strain FP1 was successfully recovered from the biofilm by plating and by DGGE, reinforcing that bioaugmentation was successfully achieved.
Anouk Duque; Vânia Bessa; Paula M. L. Castro. Bacterial community dynamics in a rotating biological contactor treating 2-fluorophenol-containing wastewater. Journal of Industrial Microbiology and Biotechnology 2014, 41, 97 -104.
AMA StyleAnouk Duque, Vânia Bessa, Paula M. L. Castro. Bacterial community dynamics in a rotating biological contactor treating 2-fluorophenol-containing wastewater. Journal of Industrial Microbiology and Biotechnology. 2014; 41 (1):97-104.
Chicago/Turabian StyleAnouk Duque; Vânia Bessa; Paula M. L. Castro. 2014. "Bacterial community dynamics in a rotating biological contactor treating 2-fluorophenol-containing wastewater." Journal of Industrial Microbiology and Biotechnology 41, no. 1: 97-104.
The main aim of this study was to investigate the performance of an aerobic granular sludge sequencing batch reactor (AGS-SBR) receiving water streams supplied with different loads of Zn(2+) (50 and 100 mg L(-1)) during an operation of 866 cycles (ca. 109 days). When the metal was not fed, chemical oxygen demand (COD), PO4(3-) and NH4(+) were efficiently removed, with efficiencies of 56, 23 and 72% respectively. DGGE profiles showed that Zn(2+) supply negatively affected the bacterial diversity and community structure of the granules. Consequently, the shock loadings with Zn(2+), particularly at the higher levels (100 mg L(-1)), affected the nutrient removal in the AGS-SBR, although the reactor still generally complied with admissible legal values concerning organic matter, nitrogen and Zn. Simultaneous removal of PO4(3-) and TSS in such conditions needs further refining but the application of aerobic granular SBR in the treatment of Zn(2+) contaminated wastewaters seems viable.
Ana P.G.C. Marques; Anouk F. Duque; Vânia S. Bessa; Raquel B.R. Mesquita; António O.S.S. Rangel; Paula M.L. Castro. Performance of an aerobic granular sequencing batch reactor fed with wastewaters contaminated with Zn2+. Journal of Environmental Management 2013, 128, 877 -882.
AMA StyleAna P.G.C. Marques, Anouk F. Duque, Vânia S. Bessa, Raquel B.R. Mesquita, António O.S.S. Rangel, Paula M.L. Castro. Performance of an aerobic granular sequencing batch reactor fed with wastewaters contaminated with Zn2+. Journal of Environmental Management. 2013; 128 ():877-882.
Chicago/Turabian StyleAna P.G.C. Marques; Anouk F. Duque; Vânia S. Bessa; Raquel B.R. Mesquita; António O.S.S. Rangel; Paula M.L. Castro. 2013. "Performance of an aerobic granular sequencing batch reactor fed with wastewaters contaminated with Zn2+." Journal of Environmental Management 128, no. : 877-882.
A rotating biological contactor (RBC) was used to treat shock loadings of 4-fluorocinnamic acid (4-FCA). Intermittent 4-FCA shocks of 35 mg L−1 were applied (ca. 3 months) with only limited mineralization occurring and accumulation of 4-fluorobenzoate (4-FBA) as an intermediate. After bioaugmentation with a degrading bacterium the RBC was able to deal with 4-FCA intermittent loading of 80 mg L−1 however, a gradual decline in RBC performance occurred, leading to 4-FBA accumulation. The degrading strain was recovered from the biofilm during 2 months but intermittent feeding may have led to diminishing strain numbers. Distinct bacterial communities in the 1st and the 5th and 10th stages of the RBC were revealed by denaturating gradient gel electrophoresis. Several isolates retrieved from the RBC transformed 4-FCA into 4-FBA but only two strains mineralized the compound. Bioaugmentation allowed removal of the fluorinated compound however intermittent feeding may have compromised the bioreactor efficiency.
Catarina L. Amorim; Anouk F. Duque; Carlos M.M. Afonso; Paula M.L. Castro. Bioaugmentation for treating transient 4-fluorocinnamic acid shock loads in a rotating biological contactor. Bioresource Technology 2013, 144, 554 -562.
AMA StyleCatarina L. Amorim, Anouk F. Duque, Carlos M.M. Afonso, Paula M.L. Castro. Bioaugmentation for treating transient 4-fluorocinnamic acid shock loads in a rotating biological contactor. Bioresource Technology. 2013; 144 ():554-562.
Chicago/Turabian StyleCatarina L. Amorim; Anouk F. Duque; Carlos M.M. Afonso; Paula M.L. Castro. 2013. "Bioaugmentation for treating transient 4-fluorocinnamic acid shock loads in a rotating biological contactor." Bioresource Technology 144, no. : 554-562.
Aerobic granular sludge is extremely promising for the treatment of effluents containing toxic compounds, and it can economically compete with conventional activated sludge systems. A laboratory scale granular sequencing batch reactor (SBR) was established and operated during 444 days for the treatment of an aqueous stream containing a toxic compound, 2-fluorophenol (2-FP), in successive phases. Initially during ca. 3 months, the SBR was intermittently fed with 0.22 mM of 2-FP added to an acetate containing medium. No biodegradation of the target compound was observed. Bioaugmentation with a specialized bacterial strain able to degrade 2-FP was subsequently performed. The reactor was thereafter continuously fed with 0.22 and 0.44 mM of 2-FP and with 5.9 mM of acetate (used as co-substrate), for 15 months. Full degradation of the compound was reached with a stoichiometric fluoride release. The 2-FP degrading strain was successfully retained by aerobic granules, as shown through the recovering of the strain from the granular sludge at the end of the experiment. Overall, the granular SBR has shown to be robust, exhibiting a high performance after bioaugmentation with the 2-FP degrading strain. This study corroborates the fact that bioaugmentation is often needed in cases where biodegradation of highly recalcitrant compounds is targeted.
Anouk F. Duque; Vânia S. Bessa; Maria F. Carvalho; Merle de Kreuk; Mark C.M. van Loosdrecht; Paula M.L. Castro. 2-Fluorophenol degradation by aerobic granular sludge in a sequencing batch reactor. Water Research 2011, 45, 6745 -6752.
AMA StyleAnouk F. Duque, Vânia S. Bessa, Maria F. Carvalho, Merle de Kreuk, Mark C.M. van Loosdrecht, Paula M.L. Castro. 2-Fluorophenol degradation by aerobic granular sludge in a sequencing batch reactor. Water Research. 2011; 45 (20):6745-6752.
Chicago/Turabian StyleAnouk F. Duque; Vânia S. Bessa; Maria F. Carvalho; Merle de Kreuk; Mark C.M. van Loosdrecht; Paula M.L. Castro. 2011. "2-Fluorophenol degradation by aerobic granular sludge in a sequencing batch reactor." Water Research 45, no. 20: 6745-6752.
A pure bacterial culture able to utilize 2-fluorophenol (2-FP) as sole carbon and energy source was isolated by selective enrichment from sediments collected from a contaminated site in Northern Portugal. 16S rRNA gene analysis showed that the organism (strain FP1) belongs to the genus Rhodococcus. When grown aerobically on 2-FP, growth kinetics of strain FP1 followed the Luong model. An inhibitory effect of increasing 2-FP concentrations was observed with no growth occurring at 2-FP levels higher than ca. 4 mM. Rhodococcus strain FP1 was able to degrade a range of other organofluorine compounds, including 2-fluorobenzoate, 3-fluorobenzoate, 4-fluorobenzoate, 3-fluorophenol, 4-fluorophenol, 3-fluorocatechol, and 4-fluorocatechol, as well as chlorinated compounds such as 2-chlorophenol and 4-chlorophenol. Experiments with cell-free extracts and partially purified enzymes indicated that the first step of 2-fluorophenol metabolism was conversion to 3-fluorocatechol, suggesting an unusual pathway for fluoroaromatic metabolism. To our knowledge, this is the first time that utilization of 2-FP as a growth substrate by a pure bacterial culture is reported.
Anouk Duque; Syed A. Hasan; Vânia Bessa; M. Fátima Carvalho; Ghufrana Samin; Dick B. Janssen; Paula M. L. Castro. Isolation and characterization of a Rhodococcus strain able to degrade 2-fluorophenol. Applied Microbiology and Biotechnology 2011, 95, 511 -520.
AMA StyleAnouk Duque, Syed A. Hasan, Vânia Bessa, M. Fátima Carvalho, Ghufrana Samin, Dick B. Janssen, Paula M. L. Castro. Isolation and characterization of a Rhodococcus strain able to degrade 2-fluorophenol. Applied Microbiology and Biotechnology. 2011; 95 (2):511-520.
Chicago/Turabian StyleAnouk Duque; Syed A. Hasan; Vânia Bessa; M. Fátima Carvalho; Ghufrana Samin; Dick B. Janssen; Paula M. L. Castro. 2011. "Isolation and characterization of a Rhodococcus strain able to degrade 2-fluorophenol." Applied Microbiology and Biotechnology 95, no. 2: 511-520.
The performance of a laboratory scale rotating biological contactor (RBC) towards shock loadings of 2-fluorophenol (2-FP) was investigated. During a period of ca. 2 months organic shock loadings of 25 mg L⁻¹ of 2-FP were applied to the RBC. As no biodegradation of 2-FP was observed, bioaugmentation of the RBC with a 2-FP degrading strain was carried out and, along ca. 6 months, organic shock loadings within a range of 25-200 mg L⁻¹ of 2-FP were applied. Complete biodegradation of 50 mg L⁻¹ of 2-FP was observed during operation of the reactor. The RBC showed to be robust towards starvation periods, as after ca. 1month of non-supply of the target compound, the reactor resumed 2-FP degradation. The inoculated strain was retained within the biofilm in the disks, as the 2-FP degrading strain was recovered from the biofilm by the end of the experiment, thus bioaugmentation was successfully achieved.
Anouk F. Duque; Vânia S. Bessa; Maria F. Carvalho; Paula M.L. Castro. Bioaugmentation of a rotating biological contactor for degradation of 2-fluorophenol. Bioresource Technology 2011, 102, 9300 -9303.
AMA StyleAnouk F. Duque, Vânia S. Bessa, Maria F. Carvalho, Paula M.L. Castro. Bioaugmentation of a rotating biological contactor for degradation of 2-fluorophenol. Bioresource Technology. 2011; 102 (19):9300-9303.
Chicago/Turabian StyleAnouk F. Duque; Vânia S. Bessa; Maria F. Carvalho; Paula M.L. Castro. 2011. "Bioaugmentation of a rotating biological contactor for degradation of 2-fluorophenol." Bioresource Technology 102, no. 19: 9300-9303.
Water treatment has become a source of concern as new pollutants and higher volumes of waste water must be treated. Emerging biological approaches, namely the use of bioreactors, for cleaning processes have been introduced. The use of bioreactors requires the development of efficient monitoring tools, preferably with real-time measurements. In this work, a couple of flow injection systems were developed and optimized for the potentiometric determination of fluoride to monitor a rotating biological contactor (RBC) bioreactor and a sequencing batch reactor (SBR) with off-line and on-line sampling. Both the RBC and the SBR bioreactors were set up for the biodegradation of the halogenated organic compound 2-fluorophenol and, as fluoride was a degradation byproduct, the process was monitored by following up its concentration. The described flow injection potentiometric methods enabled the fluoride determination within the required quantification range 0.10-100mM. The possible interferences from the growth medium were minimized in-line. The determination rate was 78 h(-1) for the off-line monitoring of RBC and 50(-1)h for the on-line monitoring of the SBR, with a sample consumption of 0.500 mL and 0.133 mL per determination, respectively. Furthermore, the overall reagent consumption was quite low. The accuracy of the system was evaluated by comparison with a batch procedure. The SBR efficiency was monitored both on-line by the flow system and off-line by HPLC, for comparison purposes.
Raquel B.R. Mesquita; Inês C. Santos; Marta F.F. Pedrosa; Anouk F. Duque; Paula M.L. Castro; António O.S.S. Rangel. Development of flow injection potentiometric methods for the off-line and on-line determination of fluoride to monitor the biodegradation of a monofluorophenol in two bioreactors. Talanta 2011, 84, 1291 -1297.
AMA StyleRaquel B.R. Mesquita, Inês C. Santos, Marta F.F. Pedrosa, Anouk F. Duque, Paula M.L. Castro, António O.S.S. Rangel. Development of flow injection potentiometric methods for the off-line and on-line determination of fluoride to monitor the biodegradation of a monofluorophenol in two bioreactors. Talanta. 2011; 84 (5):1291-1297.
Chicago/Turabian StyleRaquel B.R. Mesquita; Inês C. Santos; Marta F.F. Pedrosa; Anouk F. Duque; Paula M.L. Castro; António O.S.S. Rangel. 2011. "Development of flow injection potentiometric methods for the off-line and on-line determination of fluoride to monitor the biodegradation of a monofluorophenol in two bioreactors." Talanta 84, no. 5: 1291-1297.
This study is focused on the diversity of bacterial communities from two series of horizontal subsurface flow constructed wetlands (CW) polishing high salinity tannery wastewater. Each series was planted with Arundo donax or Sarcocornia sp. in a substrate composed by expanded clay and sand. Chemical and biochemical oxygen demand removal efficiencies were similar in each series, varying between 58 and 67% (inlet COD 218 ± 28 mg L−1) and 60 and 77% (inlet BOD5 37 ± 6 mg L−1), respectively. High numbers of culturable bacteria were obtained from substrate and root samples – 5.75 × 106-3.95 × 108 CFU g−1 recovered on marine agar and 1.72 × 107-8.46 × 108 CFU g−1 on nutrient agar. Fifty bacterial isolates were retrieved from the CW, related phylogenetically to Firmicutes, Actinobacteria, Bacteroidetes, α-, β-, and γ-Proteobacteria. Changes in the bacterial communities, from roots and substrate of each series, related to the plant species, hydraulic loading rates and along CW operation were examined using denaturating gradient gel electrophoresis (DGGE). The clustering analysis suggested that a diverse and distinct bacterial community inhabits each series, which was related to the type of plant present in each CW.
C.S.C. Calheiros; A. Teixeira; C. Pirès; A.R. Franco; A.F. Duque; L.F.C. Crispim; S.C. Moura; P.M.L. Castro. Bacterial community dynamics in horizontal flow constructed wetlands with different plants for high salinity industrial wastewater polishing. Water Research 2010, 44, 5032 -5038.
AMA StyleC.S.C. Calheiros, A. Teixeira, C. Pirès, A.R. Franco, A.F. Duque, L.F.C. Crispim, S.C. Moura, P.M.L. Castro. Bacterial community dynamics in horizontal flow constructed wetlands with different plants for high salinity industrial wastewater polishing. Water Research. 2010; 44 (17):5032-5038.
Chicago/Turabian StyleC.S.C. Calheiros; A. Teixeira; C. Pirès; A.R. Franco; A.F. Duque; L.F.C. Crispim; S.C. Moura; P.M.L. Castro. 2010. "Bacterial community dynamics in horizontal flow constructed wetlands with different plants for high salinity industrial wastewater polishing." Water Research 44, no. 17: 5032-5038.
This study focused on the diversity of bacterial communities from two series of two-stage constructed wetlands (CWs) treating tannery wastewater, under different hydraulic conditions. Series were separately planted with Typha latifolia and Phragmites australis in expanded clay aggregates and operated for 31 months. The effect of plant species, hydraulic loading and unit stage on bacterial communities was addressed through bacterial enumeration and denaturating gradient gel electrophoresis (DGGE). Diverse and distinct bacterial communities were found in each system unit, which was related in part to the type of plant and stage position (first or second unit in the series). Numerical analysis of DGGE profiles showed high diversity in each unit with an even distribution of species. No clear relation was established between the sample collection time, hydraulic loading applied and the bacterial diversity. Isolates retrieved from plant roots and substrates of CWs were affiliated with γ-Proteobacteria, Firmicutes, α-Proteobacteria, Sphingobacteria, Actinobacteria and Bacteroidetes. Both series were effective in removing organic matter from the inlet wastewater, however, based on batch degradation experiments it seems that biodegradation was limited by the recalcitrant properties of the wastewater.
Cristina Calheiros; Anouk Duque; Alexandra Moura; Isabel Henriques; Antonio Correia; António Rangel; Paula M.L. Castro. Changes in the bacterial community structure in two-stage constructed wetlands with different plants for industrial wastewater treatment. Bioresource Technology 2009, 100, 3228 -3235.
AMA StyleCristina Calheiros, Anouk Duque, Alexandra Moura, Isabel Henriques, Antonio Correia, António Rangel, Paula M.L. Castro. Changes in the bacterial community structure in two-stage constructed wetlands with different plants for industrial wastewater treatment. Bioresource Technology. 2009; 100 (13):3228-3235.
Chicago/Turabian StyleCristina Calheiros; Anouk Duque; Alexandra Moura; Isabel Henriques; Antonio Correia; António Rangel; Paula M.L. Castro. 2009. "Changes in the bacterial community structure in two-stage constructed wetlands with different plants for industrial wastewater treatment." Bioresource Technology 100, no. 13: 3228-3235.
Constructed wetlands (CWs) have been recognized as being able to effectively treat wastewater from municipal and industrial sources. This study focused on the effect of different substrates and long-term operation of horizontal subsurface flow CWs treating tannery wastewater on the bacterial communities. The CWs were planted with Typha latifolia in three types of substrate: two units with different types of expanded clay aggregates and one unit with fine gravel. Another unit with expanded clay was left unvegetated. Changes in the bacterial community related to the type of substrate, different hydraulic loading rates and along CW operation were examined using denaturating gradient gel electrophoresis (DGGE). Bacterial enumeration was also performed and several bacterial isolates were retrieved from the CWs. Phylogenetic affiliations of those isolates were obtained on the basis of 16S rRNA gene sequences and revealed that they were closely related to the genera Bacillus (TM1S1, TM1R3, TNR1 and TAR1), Paracoccus (TM1R2), Pseudomonas (TM1R1) and Halomonas (TM1S2). The type of substrate and the presence of T. latifolia had a major effect on the species richness and the structure of bacterial communities as inferred by numerical analysis of DGGE profiles.
Cristina S.C. Calheiros; Anouk F. Duque; Alexandra Moura; Isabel S. Henriques; António Correia; António O.S.S. Rangel; Paula M.L. Castro. Substrate effect on bacterial communities from constructed wetlands planted with Typha latifolia treating industrial wastewater. Ecological Engineering 2009, 35, 744 -753.
AMA StyleCristina S.C. Calheiros, Anouk F. Duque, Alexandra Moura, Isabel S. Henriques, António Correia, António O.S.S. Rangel, Paula M.L. Castro. Substrate effect on bacterial communities from constructed wetlands planted with Typha latifolia treating industrial wastewater. Ecological Engineering. 2009; 35 (5):744-753.
Chicago/Turabian StyleCristina S.C. Calheiros; Anouk F. Duque; Alexandra Moura; Isabel S. Henriques; António Correia; António O.S.S. Rangel; Paula M.L. Castro. 2009. "Substrate effect on bacterial communities from constructed wetlands planted with Typha latifolia treating industrial wastewater." Ecological Engineering 35, no. 5: 744-753.