Bioremediation of liquid effluents using synergy between Chlorella vulgaris and bacteria

Nowadays, excessive population growth, overexploitation of resources and increased industrial activity has put a huge stress on several ecosystems, with problems such as occupation of arable land and pollution of watercourses endangering human populations and habitats. One of the answers for this is the use of microalgae as it is known that they have huge potential as food and organic compounds source while occupying non-arable land as well as a largely untapped bioremediation potential. However, despite all this potential its cultivation is still largely not cost effective, as such, several methods to augment its potential are suggested. One of these is by using effluents as substrate, as several of them are rich in macronutrients. Still, one underexploited method is the use of synergy between microalgae and bacteria to increase culture growth. To this end, the microalgae Chlorella vulgaris and three different effluents were used, each with different origins and therefore different physicochemical characteristics in a series of essays. The process was evaluated by analysing parameters such as microalgae growth, COD value and macronutrient assimilation in order to depict the cultures potential as a bioremediation and microalgae growth enhancing assets. The results obtained showed that in the effluents studied, microalgae cultures were able to achieve moderate to strong growth notwithstanding problems such as high organic compounds such as phenols or high macronutrients concentration that characterize the effluents OMWW and LWW respectively. The bioremediation results depend on the parameter analysed, as microalgae showed extremely high nutrients assimilation capability while it is not the case for COD. Within these positive results differences were observed between axenic and xenic cultures, as the presence of bacteria generally served as an enhancer of growth. This was especially the case in cultures where a bacterial population indigenous to the effluent was used as it was the case with MWW. Nonetheless, as far as COD bioremediation regards, the presence of these mixed cultures while did not revealed significant divergences from pure microalgae cultures. Thus, it can be said that the use of mixed bacteria-microalgae culture in effluents is a very effective tool to enhance culture growth while simultaneously decreasing associated costs of this kind of industry and possessing good bioremediation capabilities.Hoje em dia, devido ao elevado crescimento da população mundial, assiste-se ao esgotamento dos recursos, à utilização intensiva dos espaços e à poluição decorrente das atuais atividades humanas, tornou-se necessário procurar novos meios e métodos de produção de bens, nomeadamente alimentares, com vista a minorar o impacto ambiental e económico das atividades humanas. Uma das respostas pode passar pela produção de microalgas, tais como a Chlorella vulgaris. No entanto, apesar de se reconhecer que estes microrganismos apresentam um elevado crescimento e potencial na produção de compostos de grande interesse para a alimentação humana e animal, hoje em dia a sua produção não é ainda, em muitos casos, economicamente viável, ou seja, a sua rentabilidade não compensa os elevados custos de produção associados, nomeadamente o enorme consumo de recursos hídricos e de macronutrientes. Como tal, um dos objetivos deste trabalho foi utilizar efluentes provenientes de 3 fontes diferentes para fornecer os macronutrientes necessários para o crescimento e paralelamente testar o potencial de biorremediação destas microalgas. Neste contexto, procurou-se ainda avaliar as sinergias entre a microalga e as bactérias, quer do próprio efluente, quer introduzidas propositadamente, de modo a analisar a eficácia desta cultura mista no crescimento algal e na biorremediação do efluente utilizado como substrato. Esta abordagem decorre de se saber que existe uma vasta gama de interações entre estes dois microrganismos que data praticamente desde o seu surgimento na história evolutiva da Terra. Tais interações podem ser benéficas ou não, dependendo da espécie de bactéria em questão dado que muitas são parasíticas e como tal podem levar à morte da cultura de microalgas onde estão presentes. No entanto, o uso correto de uma sinergia entre algas e bactérias pode, decorrente da maior acessibilidade a nutrientes de outra forma inacessíveis às algas existentes em culturas, gerar um melhor crescimento de microalgas que irá aumentar o rendimento em biomassa e simultaneamente proporcionar, o tratamento do efluente utilizado como substrato pela cultura. Neste trabalho, os substratos utilizados foram três efluentes, um de lagar de azeite, outro lixiviado proveniente de um aterro e ainda águas residuais urbanas. Estes efluentes de origens diferentes apresentam, como é natural, características diferentes entre si, o que foi tido em conta na sua utilização como substrato. O processo foi avaliado com base nas seguintes monitorizações: concentração de células, concentração de macronutrientes, nomeadamente N e P, COD, entre outros. O efluente de lagar de azeite (OMWW) foi o primeiro a ser utilizado e devido às suas características físico-químicas foi o que sofreu uma diluição maior para garantir que haveria condições mínimas de sobrevivência das microalgas na cultura. Foram feitas duas séries de ensaios com este efluente (a segunda com maior diluição), tendo-se verificado que o crescimento das microalgas é afetado negativamente pela presença do efluente; como esperado os ensaios com maior diluição (0.25—0.5% v/v) foram aqueles que apresentaram um crescimento bastante aceitável, comparável com a referência (sem efluente e com nutrientes sintéticos). Nesta série de ensaios verificou-se uma diminuição significativa do COD e um correspondente up-take de N e P, o que representa uma efetiva biorremediação. O segundo efluente utilizado foi um lixiviado (LWW), tendo sido incorporado a níveis entre 5% (v/v) e 10% (v/v). Tal como com o efluente anterior, foram realizadas duas séries de ensaios. Na 1ª série testou-se a adição ou não de macronutriente, N e P, ao efluente LWW. O crescimento das microalgas foi, em qualquer dos casos, significativamente inferior ao verificado para o controlo (sem efluente e com nutrientes sintéticos). O ensaio com 10% de LWW foi o que apresentou os piores resultados de crescimento. Na 2ª série de ensaios foram introduzidas propositadamente bactérias proveniente de um meio misto (aeróbio/anaeróbio), tendo verificado uma influência positiva, ainda que modesta, sobre o crescimento microalgal. Em contrapartida o seu efeito na biorremediação foi misto, com os valores de CQO a manterem-se elevados e estáveis durante o ensaio, enquanto os valores de assimilação de macronutrientes foram superiores às culturas xénicas utilizadas. O último efluente utilizado foram as águas residuais urbanas (MWW). De facto, não se ensaiou um efluente, mas sim dois proveniente de duas etapas distintas do processo de tratamento de águas residuais: após crivagem e após tratamento aeróbio. Estes efluentes foram incorporados sem e com esterilização e ainda, no caso do esterilizado, adicionando bactérias aeróbias externas. Os resultados obtidos com estes efluentes foram satisfatórios, com os biorreactores com substrato proveniente dos primeiros passos do tratamento de águas residuais a registarem elevados rácios de crescimento, com particular destaque na cultura axénica onde se encontravam bactérias do próprio efluente; as culturas mistas de algas com bactérias alóctones ao efluente por sua vez registaram picos de crescimento, mas depois entraram numa longa fase de crescimento reduzido. No que respeita à biorremediação, apenas o CQO pôde ser testado e o que se verificou foi um declínio lento, mas constante do valor deste. Os dados obtidos no final do trabalho levaram-nos à conclusão que apesar de na maioria dos casos os efluentes utilizados resultarem em crescimento de biomassa algal, os melhores resultados ocorreram nas culturas mistas de bactérias e microalgas, particularmente as existentes no efluente MWW, onde as culturas indígenas foram testadas. Isto leva-nos a concluir que de modo a se obter um melhor rendimento global de microalgas, assim como um simultâneo tratamento do efluente, a melhor solução será utilizar culturas mistas destes organismos

Induction of CD4+CD25+FOXP3+ Regulatory T Cells during Human Hookworm Infection Modulates Antigen-Mediated Lymphocyte Proliferation

Hookworm infection is considered one of the most important poverty-promoting neglected tropical diseases, infecting 576 to 740 million people worldwide, especially in the tropics and subtropics. These blood-feeding nematodes have a remarkable ability to downmodulate the host immune response, protecting themselves from elimination and minimizing severe host pathology. While several mechanisms may be involved in the immunomodulation by parasitic infection, experimental evidences have pointed toward the possible involvement of regulatory T cells (Tregs) in downregulating effector T-cell responses upon chronic infection. However, the role of Tregs cells in human hookworm infection is still poorly understood and has not been addressed yet. In the current study we observed an augmentation of circulating CD4+CD25+FOXP3+ regulatory T cells in hookworm-infected individuals compared with healthy non-infected donors. We have also demonstrated that infected individuals present higher levels of circulating Treg cells expressing CTLA-4, GITR, IL-10, TGF-β and IL-17. Moreover, we showed that hookworm crude antigen stimulation reduces the number of CD4+CD25+FOXP3+ T regulatory cells co-expressing IL-17 in infected individuals. Finally, PBMCs from infected individuals pulsed with excreted/secreted products or hookworm crude antigens presented an impaired cellular proliferation, which was partially augmented by the depletion of Treg cells. Our results suggest that Treg cells may play an important role in hookworm-induced immunosuppression, contributing to the longevity of hookworm survival in infected people

Induction of CD4+CD25+FOXP3+ Regulatory T Cells during Human Hookworm Infection Modulates Antigen-Mediated Lymphocyte Proliferation.

Submitted by Nuzia Santos ([email protected]) on 2014-12-02T12:58:23Z No. of bitstreams: 1 Induction of CD4+CD25+FOXP3+ Regulatory T Cells during Human Hookworm Infection Modulates Antigen-Mediated Lymphocyte Proliferation.pdf: 583244 bytes, checksum: 380031abcfa9a222d6ee2c5e979d06ea (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2014-12-02T13:07:36Z (GMT) No. of bitstreams: 1 Induction of CD4+CD25+FOXP3+ Regulatory T Cells during Human Hookworm Infection Modulates Antigen-Mediated Lymphocyte Proliferation.pdf: 583244 bytes, checksum: 380031abcfa9a222d6ee2c5e979d06ea (MD5)Made available in DSpace on 2014-12-02T13:07:36Z (GMT). No. of bitstreams: 1 Induction of CD4+CD25+FOXP3+ Regulatory T Cells during Human Hookworm Infection Modulates Antigen-Mediated Lymphocyte Proliferation.pdf: 583244 bytes, checksum: 380031abcfa9a222d6ee2c5e979d06ea (MD5) Previous issue date: 2011Universidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, Brazil/ Instituto Nacional de Ciencia e Tecnologia em Doenças Tropicais. BrazilUniversidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, Brazil/ Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, Brazil/ Universidade Federal de Minas Gerais. Hospital das Clínicas. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, Brazil/ Instituto Nacional de Ciencia e Tecnologia em Doenças Tropicais. BrazilUniversidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, Brazil/ Instituto Nacional de Ciencia e Tecnologia em Doenças Tropicais. BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrasilInstituto Nacional de Ciencia e Tecnologia em Doenças Tropicais. Brazil/Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrasilInstituto Nacional de Ciencia e Tecnologia em Doenças Tropicais. Brazil/Universidade Federal de Minas Gerais. Escola de Enfermagem. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, Brazil/Instituto Nacional de Ciencia e Tecnologia em Doenças Tropicais. Brazil/ Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Departamento de Parasitologia. Belo Horizonte, MG, BrazilHookworm infection is considered one of the most important poverty-promoting neglected tropical diseases, infecting 576 to 740 million people worldwide, especially in the tropics and subtropics. These blood-feeding nematodes have a remarkable ability to downmodulate the host immune response, protecting themselves from elimination and minimizing severe host pathology. While several mechanisms may be involved in the immunomodulation by parasitic infection, experimental evidences have pointed toward the possible involvement of regulatory T cells (Tregs) in downregulating effector T-cell responses upon chronic infection. However, the role of Tregs cells in human hookworm infection is still poorly understood and has not been addressed yet. In the current study we observed an augmentation of circulating CD4+ CD25+ FOXP3+ regulatory T cells in hookworm-infected individuals compared with healthy non-infected donors. We have also demonstrated that infected individuals present higher levels of circulating Treg cells expressing CTLA-4, GITR, IL-10, TGF-b and IL-17. Moreover, we showed that hookworm crude antigen stimulation reduces the number of CD4+ CD25+ FOXP3+ T regulatory cells co-expressing IL-17 in infected individuals. Finally, PBMCs from infected individuals pulsed with excreted/secreted products or hookworm crude antigens presented an impaired cellular proliferation, which was partially augmented by the depletion of Treg cells. Our results suggest that Treg cells may play an important role in hookworm-induced immunosuppression, contributing to the longevity of hookworm survival in infected people

Hookworm products ameliorate dextran sodium sulfate-induced colitis in BALB/c mice.

Background: Several lines of evidence have shown that helminthiasis can significantly reduce disease severity in animal models of intestinal inflammation, airway inflammation/hyperreactivity, diabetes, and multiple sclerosis. Identification and characterization of helminth-derived immunomodulatory molecules that contribute to anticolitis effects could lead to new therapeutic approaches in inflammatory bowel diseases (IBDs) without the need for helminth infection. We evaluated the therapeutic potential of adult human hookworm, Ancylostoma ceylanicum, crude (Aw) and excreted/secreted (ES) products on dextran sulfate sodium (DSS)-induced colitis in BALB/c mice. Methods: Colitis was induced by 5% DSS oral administration for 7 days. Clinical disease severity was monitored daily during concomitant intraperitoneal treatment with helminth-derived products. Additionally, several pathways of immunological modulation induced by A. ceylanicum products (MPO, EPO, Th1, Th2, and Th17 cytokine responses) in the inflamed intestinal microenvironment were assessed. Finally, the histopathological profile of the colon was characterized. Results: Hookworm products are able to modulate the potent proinflammatory response induced by DSS, mainly through the downregulation of Th1 and Th17 cytokines. These proteins also reduce clinical and colonic microscopic inflammation scores as well as EPO and MPO activity. Conclusions: Ancylostoma ceylanicum Aw and ES mediators have an important therapeutic potential in experimental colitis in mice, which may provide a more socially acceptable form of therapy for patients with IBDs as opposed to using living worms. Our results support the urgency of further isolation and recombinant expression of active hookworm products responsible for the beneficial effects on colitis

Ano IX, número 19

Espaço e Economia: Revista Brasileira de Geografia Econômica, além dos artigos em fluxo contínuo, inclui nesta edição o Dossiê Oeste Metropolitano do Rio de Janeiro, organizado pelos professores Marcio Rufino Silva, Denise de Alcantara, Leandro Dias de Oliveira e André Santos da Rocha (PPGGEO e PPGDT-UFRRJ)

Search for Scalar Diphoton Resonances in the Mass Range 65−60065-600 GeV with the ATLAS Detector in pppp Collision Data at s\sqrt{s} = 8 TeVTeV

A search for scalar particles decaying via narrow resonances into two photons in the mass range 65–600 GeV is performed using $20.3\text{}\text{}{\mathrm{fb}}^{-1}$ of $\sqrt{s}=8\text{}\text{}\mathrm{TeV}$ $pp$ collision data collected with the ATLAS detector at the Large Hadron Collider. The recently discovered Higgs boson is treated as a background. No significant evidence for an additional signal is observed. The results are presented as limits at the 95% confidence level on the production cross section of a scalar boson times branching ratio into two photons, in a fiducial volume where the reconstruction efficiency is approximately independent of the event topology. The upper limits set extend over a considerably wider mass range than previous searches

Search for Higgs and ZZ Boson Decays to J/ψγJ/\psi\gamma and Υ(nS)γ\Upsilon(nS)\gamma with the ATLAS Detector

A search for the decays of the Higgs and $Z$ bosons to $J/\psi\gamma$ and $\Upsilon(nS)\gamma$ ($n=1,2,3$) is performed with $pp$ collision data samples corresponding to integrated luminosities of up to $20.3\mathrm{fb}^{-1}$ collected at $\sqrt{s}=8\mathrm{TeV}$ with the ATLAS detector at the CERN Large Hadron Collider. No significant excess of events is observed above expected backgrounds and 95% CL upper limits are placed on the branching fractions. In the $J/\psi\gamma$ final state the limits are $1.5\times10^{-3}$ and $2.6\times10^{-6}$ for the Higgs and $Z$ bosons, respectively, while in the $\Upsilon(1S,2S,3S)\,\gamma$ final states the limits are $(1.3,1.9,1.3)\times10^{-3}$ and $(3.4,6.5,5.4)\times10^{-6}$, respectively

Measurements of the Total and Differential Higgs Boson Production Cross Sections Combining the H??????? and H???ZZ*???4??? Decay Channels at s\sqrt{s}=8??????TeV with the ATLAS Detector

Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3~fb$^{-1}$ of $pp$ collisions produced by the Large Hadron Collider at a center-of-mass energy of $\sqrt{s} = 8$ TeV and recorded by the ATLAS detector. Cross sections are obtained from measured $H \rightarrow \gamma \gamma$ and $H \rightarrow ZZ ^{*}\rightarrow 4\ell$ event yields, which are combined accounting for detector efficiencies, fiducial acceptances and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be $\sigma_{pp \to H} = 33.0 \pm 5.3 \, ({\rm stat}) \pm 1.6 \, ({\rm sys}) \mathrm{pb}$. The measurements are compared to state-of-the-art predictions.Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3  fb-1 of pp collisions produced by the Large Hadron Collider at a center-of-mass energy of s=8  TeV and recorded by the ATLAS detector. Cross sections are obtained from measured H→γγ and H→ZZ*→4ℓ event yields, which are combined accounting for detector efficiencies, fiducial acceptances, and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be σpp→H=33.0±5.3 (stat)±1.6 (syst)  pb. The measurements are compared to state-of-the-art predictions.Measurements of the total and differential cross sections of Higgs boson production are performed using 20.3 fb$^{-1}$ of $pp$ collisions produced by the Large Hadron Collider at a center-of-mass energy of $\sqrt{s} = 8$ TeV and recorded by the ATLAS detector. Cross sections are obtained from measured $H \rightarrow \gamma \gamma$ and $H \rightarrow ZZ ^{*}\rightarrow 4\ell$ event yields, which are combined accounting for detector efficiencies, fiducial acceptances and branching fractions. Differential cross sections are reported as a function of Higgs boson transverse momentum, Higgs boson rapidity, number of jets in the event, and transverse momentum of the leading jet. The total production cross section is determined to be $\sigma_{pp \to H} = 33.0 \pm 5.3 \, ({\rm stat}) \pm 1.6 \, ({\rm sys}) \mathrm{pb}$. The measurements are compared to state-of-the-art predictions