Efficient ammonium removal from marine aquaculture wastewater with microalgal-bacterial granular sludge technology

Water recirculation in marine aquaculture is fundamental for the protection of water resources and for the sector sustainability as it enables to reduce water usage 1. Microalgal-bacterial granular sludge (MBGS) has the potential to increase the removal efficiency of pollutants from wastewaters benefiting from the diverse metabolism allowing water recirculation. Moreover, MBGS would allow costs reduction both in biomass separation from the treated water given the rapid settling properties and in aeration due to microalgae oxygen production 2.This study aimed to develop MBGS able to treat marine aquaculture effluents. For that, a lab-scale photo sequencing batch reactor was inoculated with activated sludge, previously adapted to salty wastewater, and a microalgae consortium enriched from water collected at a marine aquaculture. Feeding composition was established to simulate marine aquaculture streams. The aggregation of microalgal and bacterial biomass to form granular structures occurred rapidly. Throughout the operation, dark green granules with a dense and compact structure became predominant together with an increase in chlorophyll and carotenoids content in biomass. Ammonia was absent from the reactor effluent, but the nitrite levels were often above the toxicity levels for fish. Nevertheless, the dissolved oxygen concentration in the treated water was high (> 8.63 mg/L). The microalgal-bacterial granules proved to be efficient in producing streams with high dissolved oxygen levels, lowering the needed of water oxygenation before reuse and without ammonium ions. However, for water recirculation, improvement of the nitrite removal is needed to maintain the levels below the fish toxicity levels.info:eu-repo/semantics/publishedVersio

Microbial degradation of fluorinated compounds : studies on biodegradation mechanisms and biotreatment systems

Fluoroorganics are an important class of chemicals compound used in a vast number of applications, including pharmaceutical, agricultural and industrial applications, leading to their disposal and accumulation in the environment. Therefore, it is important to understand and explore the biodegradation mechanisms for their removal. The work described in this thesis aimed to investigate the potential of single bacterial strains for biotransformation of fluoroorganics with different complexity as well as to explore their degradation and fate on biofilm bioreactors. In contaminated environments biodegradation can be affected by different factors. In this study, the effect of different parameters on the biodegradation of fluoroanilines (FAs) by Labrys portucalensis F11 was investigated. Strain F11 was able to degrade FAs as sole source of carbon and nitrogen nevertheless supplementation of the culture medium with nitrogen proved to be beneficial for the degradation. Strain F11 was also able to degrade FAs when cells were previously induced for haloaromatic degradation with fluorobenzene (FB). Indeed, higher removal capacity and substrate degradation rates were achieved using FB-induced cells. Co-metabolism of FAs in the presence of FB was also possible but a competitive mechanism between the substrates for the active sites of the enzymes involved in their degradation occurred. A strain capable of aerobically degrading 4-fluorocinnamic acid (4-FCA), strain S2, was isolated from a biofilm bioreactor and identified as belonging to the genus Rhodococcus. Strain S2 was able to mineralize 4-FCA as a sole carbon source but the presence of an easy degradable carbon source in the culture medium allowed a faster 4-FCA removal. However, 4-FCA concentrations higher than 1 mM led to a decrease in cell growth rate and in substrate degradation rate, indicating a toxic effect of this compound on S2 cells. A metabolic pathway for the degradation of 4-FCA by strain S2 is proposed on the basis of the identified intermediates. 4-Fluorobenzoate (4-FBA) was the major transient accumulated intermediate and for the first time trans, trans-muconate was reported as an intermediate in a biodegradation pathway. Biological degradation of 4-FCA in rotating biological contactor (RBC) was studied. After development of a stable biofilm, 35 mg L-1 of 4-FCA was intermittently fed to the bioreactor during 2 months, however only limited mineralization occurred. Therefore, the RBC was inoculated with a suspended culture of strain S2 in order to enhance the reactor performance. After bioaugmentation mineralization of 4-FCA was achieved however, a decrease in 4-FCA removal along bioreactor operation was observed. Apart from strain S2, two other 4-FCA degrading strains were isolated from the biofilm. After bioaugmentation, the degraders remained in the bioreactor by the end of the experiment but the intermittent feeding of the target compound probably led to lower cell numbers. Nevertheless, the study reinforced the need of bioaugmentation when dealing with recalcitrant compounds. Fluoroquinolones (FQs) are fluorinated antibiotics, which contamination and persistence in several environmental matrices have been well documented in the past years. Labrys portucalensis was capable to degrade the selected FQs, namely ofloxacin, norfloxacin and ciprofloxacin, when supplied individually or as a mixture, in the presence of an easy degradable carbon source. For concentrations of FQs higher than 3.5 μM an inhibitory effect on growth of the strain was observed. The removal capacity of strain F11 also decreased at high FQ concentration and stoichiometric fluoride release was not achieved. Several intermediates were identified from the degradation of each FQ and the piperazine ring and the fluorine substituent seemed to be the targets of the enzymatic attack. A granular sludge sequencing batch reactor (SBR), established with activated sludge from a wastewater treatment plant (WWTP), was operated for the treatment of an aqueous stream containing FQs. The effects of FQs on different biological processes, such as Chemical Oxygen Demand (COD), nitrogen and phosphorous removal by aerobic granular sludge were investigated. Overall, no significant alterations on COD effluent levels were registered. Nitrifiers present in the granular sludge were not affected by the presence of FQs however the activity of denitrifiers and phosphate accumulating organisms (PAO) seemed to be inhibited. Sorption and desorption of FQs onto aerobic granules occurred. During reactor operation the microbial community dynamics was monitored by plating the biofilm and by 16S DGGE. Shifts in the microbial communities due to FQs exposure were observed, however some bacteria seemed to be resistant to the selective pressure exerted by the antibiotics.Os compostos fluoorgânicos são uma importante classe de compostos químicos utilizados num grande número de aplicações a nível farmacêutico, agrícola e industrial, e ocorrendo a sua deposição e acumulação no ambiente. Como tal, torna-se relevante compreender e explorar os mecanismos de biodegradação destes compostos. O trabalho descrito nesta tese tem como objectivo investigar o potencial de estirpes bacterianas na biotransformação de compostos fluoroorgânicos de diferente complexidade, bem como explorar a remoção desses mesmos compostos em reactores de biofilme. Um processo de biodegradação pode ser influenciado por diferentes factores. Neste estudo, foi investigada a bioiodegradação de fluoroanilinas (FAs) pela estirpe bacteriana Labrys portucalensis F11, conhecida plea sua capacidade metabólica de degradar compostos fluorados. A estirpe F11 mostrou ser capaz de degradar FAs como única fonte de fonte de carbono e azoto no entanto, a adição de uma fonte de azoto ao meio de cultura provou ser benéfica para a degradação. A remoção de FAs pela estirpe F11 com células previamente induzidas para a degradação de compostos halogenados com fluorobenzeno (FB) levou a um aumento da capacidade de remoção e das taxas de remoção do substrato. A degradação de FAs em co-metabolismo com FB foi também observada contudo verificouse a ocorrência de mecanismos de competição entre os substratos para o sítio activo das enzimas envolvidas na degradação. Uma estirpe capaz de degradar ácido 4-fluorocinâmico (4-FCA) em condições aeróbias, (estirpe S2) foi isolada de um bioreactor de biofilme e identificada como pertencendo ao género Rhodococcus. A estirpe S2 mostrou ser capaz de mineralizar 4-FCA como única fonte de carbono, mas a presença de uma fonte de carbono facilmente degradável no meio de cultura acelerou a remoção de 4-FCA. No entanto, concentrações de 4-FCA superiores a 1 mM levaram a uma diminuição da taxa de crescimento celular e da taxa de degradação, demonstrando o efeito tóxico deste composto. A via metabólica de degradação de 4-FCA foi proposta com base nos intermediários identificados. O metabolito 4-fluorobenzoato (4- FBA) foi aquele que se acumulou em maior quantidade e, pela primeira vez o metabolito trans, trans-muconate foi reportado como intermediário numa via de biodegradação. A degradação biológica de 4-FCA num reactor de biodiscos (RBC) foi também estudada. Após o desenvolvimento de um biofilme estável, o reactor foi intermitentemente alimentado com 35 mg L-1 de 4-FCA durante dois meses, no entanto, a mineralização do composto foi diminuta. Deste modo, o RBC foi inoculado com uma cultura da estirpe isolada S2 de forma a melhorar o desempenho do reactor. Após bioaumento a mineralização de 4-FCA foi alcançada mas observou-se uma diminuição na capacidade de degradação de 4-FCA ao longo do tempo de operação do reactor. Para além da estirpe S2, duas outras estirpes capazes de degradar 4-FCA foram isoladas do biofilme. Após o bioaumento, as estirpes degradadoras permaneceram no reactor até ao final da experiência, mas a alimentação intermitente com 4-FCA levou provavelmente a uma diminuição do número de células. No entanto, o estudo reforçou a ideia de que a estratégia de bioaumento é necessária quando se pretende remover compostos recalcitrantes. As fluoroquinolonas (FQs) são antibióticos fluorados, cuja contaminação e persistência em várias matrizes ambientais têm sido bem documentada. A estirpe Labrys portucalensis foi capaz de degradar as FQs seleccionadas, nomeadamente, ofloxacina, ciprofloxacina e norfloxacina, quando facultadas individualmente ou como uma mistura, na presença de uma fonte de carbono facilmente degradável. Para concentrações de FQs superiores a 3.5 μM foi observado um efeito inibitório no crescimento celular e na capacidade de remoção. A libertação estequiométrica de ião fluoreto nunca foi observada. Vários intermediários foram identificados a partir da degradação de cada FQ e, o anel de piperazina e o átomo de fluor da molécula parecem ser os principais alvos de ataque enzimático. Um reactor granular sequencial em batch (SBR), estabelecido com lamas activadas de uma estação de tratamento de águas residuais (WWTP), foi operado para o tratamento de uma corrente aquosa contendo FQs. Os efeitos da FQs em diferentes processos biológicos, tais como a carência química de oxigénio (CQO), a remoção de azoto e remoção de fósforo foram investigados. De uma forma geral não foram registradas alterações significativas nos níveis de COD do efluente. As bactérias nitrificantes presentes nos grânulos não foram afectadas pela presença de FQs mas, a actividade das bactérias denitrificantes e organismos acumuladores de fosfato parece ser inibida. Foi observada adsorção e desadsorção de FQs aos grânulos aeróbicos. Durante a operação do reactor a dinâmica da comunidade microbiana presente nos grânulos aeróbios foi avaliada por electroforese em gel de gradiente desnaturante e por plaqueamento do biofilme. Foram observadas alterações na comunidade microbiana devido à exposição às FQs, no entanto, algumas bactérias parecem ser resistentes à pressão selectiva exercida pelos antibióticos

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

© 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research