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Sistematização da experiência da cooperapas: uma cooperativa de produtores agroecológicos de parelheiros, São Paulo/SP / Systematization of experience CooperAPAs: a cooperative of agroecological producers Parelheiros, São Paulo/ SPMara Adriana Coradello 16 February 2016 (has links)
A transição agroecológica, enquanto um processo de estímulo à adoção de práticas agrícolas sustentáveis implica na gradual construção do conhecimento agroecológico, por meio da troca de saberes, experiências e interpretação dos (as) agricultores (as) sobre os contextos em que vivem e produzem, configurando-se em um modo alternativo de produção, em contraponto ao modelo atual convencional. Novos caminhos que tragam a conservação da biodiversidade, a autorrealização individual e comunitária, e a autogestão política e econômica são prioritários e urgentes. A presente pesquisa teve por objetivo sistematizar a experiência de transição agroecológica da CooperAPAs, localizada em Parelheiros, zona sul do município de São Paulo, por meio da identificação de representações de agroecologia, relações saúde, ambiente e políticas públicas, bem como os principais interesses e dificuldades de agricultores e técnicos envolvidos em algum momento específico da trajetória de formação, implementação e/ou desenvolvimento da CooperAPAs. Foi utilizado o método de sistematização de experiências, tendo como instrumentos de pesquisa a análise documental, entrevistas e oficina de construção da linha do tempo. De modo geral, os participantes reconheciam impactos positivos e negativos de suas ações sobre a saúde e o ambiente. Dentre as necessidades identificadas, destacou-se maior sensibilização e empoderamento de todos os cooperados, para que possam contribuir mais ativamente no fortalecimento da cooperativa, a fim de garantir maior acesso às políticas públicas vigentes, ao mercado, e à comercialização, melhorando, consequentemente, condições socioambientais e econômicas destes agricultores. Para tal, recomenda-se a adoção, pela cooperativa, de estratégias socioeducativas participativas, como a Aprendizagem Social, que favoreçam o diálogo, a negociação de conflitos e a gestão compartilhada, como um novo caminho para a CooperAPAs. / The agroecological transition, as an incentive to process the adoption of sustainable agricultural practices, implies the gradual construction of agroecological knowledge through the exchange of knowledge, experiences and interpretation of the farmers about the contexts in which they live and produce by setting up an alternate mode of production, in contrast to conventional current model. New ways to bring biodiversity conservation, self individual achievement and community, and the political and economic self-management, are priorities and urgent. This study aimed to systematise the agroecological transition experience of CooperAPAs, located in Parelheiros, south zone of São Paulo, through the identification of agroecology representations, healthy relationships, environment and public policy, and the main interests and difficulties of farmers and technicians involved in any specific time of training course, implementation and / or development of CooperAPAs. We used the method of systematization of experiences, having as research tools to document analysis, interviews and the timeline building workshop. In general, participants recognized both positive and negative impacts of their actions on health and the environment. Among the identified needs, there is increased awareness and empowerment of all members, so that they can contribute more actively in strengthening the cooperative in order to ensure greater access to existing public policies, market, and marketing, improving, consequently, social, environmental and economic conditions of these farmers. To this end, it recommends the adoption by the cooperative, participatory social and educational strategies such as social learning, to encourage dialogue, conflict negotiation and shared management, as a new way to CooperAPAs.
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Produção de xilooligossacarídeos a partir de resíduos lignocelulósicos e fungos filamentososMenezes, Bruna da Silva January 2018 (has links)
Xilooligossacarídeos (XOS) são produzidos a partir materiais lignocelulósicos contendo xilanos através de métodos químicos, hidrólise enzimática direta de um substrato susceptível à ação de xilanases e outras enzimas líticas, ou uma combinação de tratamentos químicos e enzimáticos. Os XOS são reconhecidos por trazerem benefício a saúde e são considerados ingredientes prebióticos. A utilização de resíduos agro-industriais produzidos no Rio Grande do Sul, tais como a casca de arroz, a casca de soja e o extrato de malte proveniente de cervejarias tornam-se substratos com grande potencial para a produção da enzima xilanase, principalmente em cultivo em estado sólido. Neste trabalho, foram analisados o potencial de diversos fungos selvagens e de um fungo recombinante na produção da enzima xilanase e outras enzimas importantes para a hidrólise de biomassa lignocelulósica, e a aplicação destes microrganismos para a produção de XOS em cultivos em estado sólido. Através de uma seleção de fungos foi possível definir o Aspergillus brasiliensis BLf1 como maior produtor de xilanase em cultivo sobre casca de arroz, obtendo atividade de 120,5 U.g-1 substrato. Nesta seleção foram analisadas também as enzimas celulase, β-glicosidase e β-xilosidase Um planejamento experimental fracionário 2(5-1) deste fungo selecionado e do fungo recombinante Aspergillus nidulans XynC A773 determinaram variáveis que influenciam a produção da enzima xilanase, chegando a uma atividade máxima de 230,7 U.g-1 para A. brasiliensis BLf1 e 187,9 U.g-1 para A. nidulans XynC A773. Posteriormente, estas preparações enzimáticas foram aplicadas à casca de arroz para hidrolisar sua estrutura hemicelulósica polimérica e obter xilolossacarídeos (37,25 mg de XOS.g-1 de substrato e 75,92 mg de XOS.g-1 de substrato, respectivamente). Por fim, foi avaliado o potencial prebiótico de XOS obtidos. Os resultados deste estudo revelaram o crescimento de L. plantarum BL011 e B. lactis BB-12 em XOS, com um aumento de massa celular seca de até 1,7 g.L-1 em 120h. Os resultados obtidos neste trabalho sugerem que é possível a obtenção de XOS a partir de resíduos abundantes no Estado e que os mesmos possuem potencial para serem utilizados como prebióticos, podendo, portanto, ser usados em aplicações relacionadas aos alimentos funcionais. / Xylooligosaccharides (XOS) are produced from lignocellulosic materials containing xylan by chemical methods, direct enzymatic hydrolysis of susceptible substrates using xylanases and other lytic enzymes, or a combination of chemical and enzymatic treatments. XOS are recognized for bringing benefit to health of the host and are considered prebiotic ingredients. The use of lignocellulosic residues produced in Rio Grande do Sul, such as rice husk, soybean hulls, and spent malt from brewery hold potential for the production of xylanase enzyme, especially under solid-state cultivation. In this work, several wild strains of fungi and one recombinant strain were tested for their potential of producing xylanase and their application in solid-state cultivation to obtain XOS. It was possible to define the Aspergillus brasiliensis BLf1 as the best producer of xylanase on rice husk, obtaining an activity of 120.5 U.g-1. Other important lytic enzymes were also analyzed: cellulase, β-glucosidase, and β-xylosidase The statistical experiment fractional factorial design 2(5-1) of cultures of this fungus and of the recombinant strain Aspergillus nidulans XynC A773 defined the variables that influenced the production of xylanase, showing maximal activities of 230.7 U.g-1 for A. brasiliensis BLf1 and 187.9 U.g-1 for A. nidulans XynC A773. Subsequently, these enzymatic preparations were applied to rice husk to hydrolyse its polymeric hemicellulosic structure and obtain xylooligosaccharides (37.25 mg XOS.g-1 substrate and 75.92 mg XOS.g-1 substrate, respectively). Finally, the prebiotic potential of XOS was evaluated by using them to grow L. plantarum BL011 and B. lactis BB-12, showing an increase in the dry cell mass of 1.7 g.L-1 at 120 hours. The results obtained in this research suggest that it is possible to obtain XOS from agro industrial residues of local production and they have the potential to be used as prebiotics, and could be used in food related applications.
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Estudo da produção de metabólitos por Pseudomonas aeruginosa : Ramnolipídios e Polihidroxialcanoatos (PHAs) /Costa, Siddhartha Georges Valadares Almeida de Oliveira. January 2010 (has links)
Resumo: O presente trabalho visou estudar a produção de biossurfactante e PHAs de Pseudomonas sp. em substratos alternativos oriundos do processamento de alimentos bem como determinar as propriedades, composição química e aplicações dos compostos obtidos. Foram isoladas 21 cepas bacterianas, sendo que duas cepas demonstraram capacidade de crescer no meio de cultivo proposto e produzir ramnolipídios e PHAs. Estas cepas foram identificadas como Pseudomonas aeruginosa e receberam as seguintes terminações: P. aeruginosa L2-1 e P. aeruginosa B1-3. Com relação a caracterização de ramnolipídios e PHAs, suas composições variaram de acordo com a fonte de carbono e a linhagem utilizada na fermentação. O meio manipueira adicionado com óleo de fritura (MOF) apresentou os melhores resultados, alcançando uma produção de PHA de 39% do peso seco de células e uma produção de ramnolipídios de 660 mg/L. A manipueira se mostrou um substrato alternativo com potencial para a produção de ramnolipídios e PHAs, principalmente quando adicionada com óleo de fritura, além de ser uma solução do ponto de vista ambiental e também agregar valor a estes resíduos. A manipueira adicionada de óleo de fritura pode reduzir os custos de produção permitindo a obtenção concomitante de ramnolipídios e PHAs. O ramnolipídio produzido pela linhagem P. aeruginosa L2-1 no substrato manipueira adicionado de óleo de fritura foi recuperado e apresentou excelentes propriedades tenso-ativas, (baixos valores de concentração micelar crítica e de tensão superficial e interfacial, excelente atividade emulficante e estabilidade da emulsão), além de potencial para uso na remediação de ambientes contaminados, removendo até 89% de petróleo na areia após processo de lavagem, conferindo características semelhantes e algumas vezes melhores que o ramnolipídio comercial JBR599 (Jeneil Biosurfactant Co.) / Abstract: This work evaluated the rhamnolipid and PHAs production by Pseudomonas sp. in alternative low-cost substrates from food processing, determining the properties, applications and chemistry composition of compounds obtained. Were isolated 21 strains, being that 2 isolates were able to growth and produce rhamnolipids and PHAs in the substrates. These bacteria were identified as Pseudomonas aeruginosa. The polymers and surfactants produced were characterized by gas-chromatography mass spectrophotometry (GC-MS) and by high performance liquid chromatography-MS (HPLC-MS), and their composition was found to vary with the carbon source and the strain used in the fermentation. The best overall production of rhamnolipids and PHAs was obtained with cassava wastewater added with waste cooking oil (CWO) as the carbon source, with PHA production corresponding to 39% of the cell dry weight and rhamnolipids production being 660 mg/L. It would appear that CWO has the highest potential as alternative substrate, and its use may contribute to a reduction in the overall environmental impact generated by discarding such residues. The rhamnolipid produced by P. aeruginosa L2-1 in CWO showed excellent tension-active properties (low values of critic micellar concentration and superficial and interfacial tensions) and potential to use in remediation of contaminated environmental, removing 89% of petroleum after washing process in sand, with characteristics similar or better than commercial rhamnolipid JBR599 (Jeneil Biosurfactant Co.) / Orientador: Jonas Contiero / Coorientador: Marcia Nitschke / Banca: José Gregório Cabrera Gomez / Banca: Marcos Rogério Tótola / Banca: Humberto Márcio Santos Milagre / Banca: Lucia Regina Durrant / Doutor
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Antimicrobial, anticancer and catalytic activities of green synthesized Avocado seed extract-gold nanoparticlesNgungeni, Yonela January 2019 (has links)
>Magister Scientiae - MSc / Nature through billions of years of trial and error has produced an immeasurable amount of
natural systems like plants, birds and animals. The intelligence of nature is hidden in these
natural systems and researchers are turning towards “Nature’s intelligence” to find inspiration
and advance novelty in the development of nanomaterials. Gold nanoparticles (AuNPs) have
unique optical, electronic and physicochemical features which has gained them popularity and
widespread exploitation in various applications. The conventional methods used for AuNPs
synthesis employs toxic chemicals which makes these NPs unsafe for biomedical applications.
Hence, there is a search for new, ‘green’ and more cost effective methods for AuNPs synthesis.
Plant extracts are regarded as a highly desirable system for nanoparticle synthesis due to their
tremendous capability to produce a wide range of phytochemicals that can act as reducing
agents. The main goal of this study was to synthesize AuNPs in a cost effective manner without
the use of toxic chemicals in the synthesis process. Avocado seeds which are an agricultural
waste by-product were used for the biosynthesis of AuNPs. The study reports on the synthesis
optimization, characterization and activities of the biogenic AuNPs.
The avocado seed extract mediated - AuNPs (AvoSE-AuNPs) were optimized by varying
reaction parameters and characterized by UV-visible, Dynamic Light Scattering (DLS) and
High Resolution Transmission Electron Microscopy (HRTEM), Zetasizer and Fourier
Transform Infrared Spectroscopy (FTIR). The formation of AvoSE-AuNPs had an absorption
maximum at 534 nm. HRTEM and DLS confirmed that the NPs were polydispersed and present
in different shapes. The presence of phytochemical constituents on the AvoSE-AuNPs were
confirmed by FTIR. Their potential antibacterial activity was tested on bacterial strains known
to exhibit resistance to a number of current antibiotics. The catalytic activity of AvoSE-AuNPs
was also assessed as a means to contribute to the development of new methods aimed at
alleviating organic pollutants such as nitrophenols in the environment. The AvoSE-AuNPs
demonstrated excellent catalytic activity in the reduction of 4-NP by NaBH4 as shown by the
rapid decrease in the nitrophenolate absorption band at 400 nm and the appearance of new
absorption band at 298 nm, revealing the formation of the 4-aminophenol. Furthermore, the
rate constants calculated demonstrated that the reaction occurs faster in the presence AvoSEAuNPs. The AvoSE-AuNPs showed low significant cytotoxicity. Cell cycle analysis was
conducted to further investigate the apparent exhibited toxicity of the AvoSE-AuNPs. The
results showed that in both cell lines treated with AvoSE-AuNPs and AvoSE there was a
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disruption in the regulation of cell cycle. Cell cycle analysis helped improve understanding of
the low cytotoxicity observed by the MTT assay results.
The results presented in this study clearly demonstrate the feasibility of using AvoSE for the
synthesis of AuNPs. This study demonstrated that AvoSE mediated AuNPs synthesis is a
greener alternative as it abides by the green chemistry principles. Furthermore, the study
outcomes contributed to minimizing environmental pollution by finding use for agricultural
waste and thus ultimately adding value to the field.
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The Swedish socio-technical agro-food system and how it may transition to a more sustainable state through an increased cultivation of grain-legumesKlingspor, Charlotte, Philipson, Linda January 2021 (has links)
Due to unsustainable production and consumption patterns that cause climate changes, current socio-technical systems, such as the agro-food system, must rapidly undergo sustainability transitions. To transition socio-technical systems is however complex and it usually takes decades, and it is therefore crucial to study how socio-technical systems can transition faster. Aim – This study aims to investigate under what circumstances a sustainability transition through an increased cultivation of grain-legumes in Sweden can take place and be accelerated. In order to guide the study and thus fulfil the purpose, two research questions have been formulated: 1) “What are the current main factors that hinder a sustainability transition in terms of an increased cultivation of grain-legumes in the current agricultural value chain of crop production in Sweden?” 2) “What prerequisites are required to accelerate sustainability transitions in the agricultural value chain of crop production in terms of an increased cultivation of grain-legumes in Sweden?” Method – The methodology used is a qualitative case study of the Swedish agricultural value chain of crop production. The data was collected through interviews, literature review and webinars. The data collected through interviewing was analyzed by using a thematic analysis. Findings – One main hindering factor refer to the absence of certain value chain processes, both when it comes to actors that can provide Swedish plant-based food producers with extracted proteins from grain-legumes and when it comes to actors that can receive, sort, peel and pack grain-legumes for human consumption at an industrial level. Other main hindering factors regards the lack of financial incentives at several levels as well as a structured and stabilized agricultural socio-technical regime characterized by path dependencies and lock-ins. The found prerequisites required in order to accelerate sustainability transitions include for instance having certain value chain processes to come into place, steer large investments and educated people in the right direction to drive innovation and development as well as an increased sustainability transitioning pressure from the civil society in Sweden. Implications – The findings of this thesis can increase the knowledge of actors engaged in the agricultural value chain of crop production, but also provide valuable insights for the whole Swedish agro-food sector. This study also provides insights regarding how a sustainability transition can be accelerated based on the findings from the studied case. Another implication is that a larger focus, when researching sustainability transitions, should be put on the role of civil society to understand and facilitate faster sustainability transitions in socio-technical systems. Limitations – The political perspective is not considered, the internal strategies of actors have not been investigated and the focus has only been at the environmental dimension of sustainability, not on the social or economic dimensions.
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Impact of social-ecological changes on resilience in the Senegalese SahelÅberg, Frida January 2021 (has links)
Understanding how social-ecological changes influence the resilience of dryland agro-silvo-pastoral systems can offer new perspectives on current sustainability challenges. In this study I use mixed methods to explore how resilience thinking can guide development towards sustainable and just future pathways in the Sahelian part of northern Senegal. A combined analysis of regional statistical data and local actors’ perceptions of recent development revealed five key patterns of change: 1) decreased annual precipitation, 2) lack of pastures and environmental degradation, 3) improved rural water access and an opening-up of previously isolated areas, 4) adaptation strategies, and 5) decentralization. Participants’ rankings of context-specific resilience metrics based on the seven principles for building resilience, indicate a low to moderate current resilience of the agro-silvo-pastoral system and a decline in general system resilience over the past decades. The analysis highlights the need for greater recognition of pastoral mobility and groundwater recharge dynamics in natural resource management, along with challenges of inequities and power assymetries among actors, while also pointing to the potential of local initiatives to support development in the Senegalese Sahel. By synthesizing changes and assessing their influence on the resilience of the agro-silvo-pastoral system, the study shows how resilience assessments can be used to understand system dynamics and illustrate development paradoxes in the Senegalese Sahel.
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Environmental sustainability through participatory approaches : socio-geographic assessment of the Mathenjwa tribal authority landscape, Northern KwaZulu-NatalAlexander, Patrick James 21 June 2013 (has links)
Development, environmental sustainability, agriculture and livelihoods are dimensions
that are often considered antagonistic. By thinking at the landscape level however,
innovative opportunities arise for simultaneity as these entities manifest spatially and
require communication across disciplines. Trans-frontier Conservation Areas (TFCAs)
embrace this thinking. These are large areas that cut across two or more international
boundaries, include within them at least one Protected Area (PA) and other multiple
resource use areas, including human dwellings and cultivated areas. Similarly,
ecoagriculture is an innovative approach to land use management as it seeks to spatially
synergise agriculture, livelihoods and biodiversity conservation across space and
requires an awareness of landscape-level issues by land users, a condition which is not
necessarily met. Such landscape thinking stems from the fact that if a piece of land is
subject to rigorous conservation, it will fail if the surrounding areas are degraded.
Additionally, it has been shown that agriculture often benefits from the nearby presence
of natural areas for ecosystem services such as pollination, pest management, and
erosion control. As such, multifunctional landscape mosaics together with small scale
farmers, not large scale monocultures, are the key to global food security, as the former
more effectively links agricultural intensification to hunger reduction. In order to
ascertain an integrated understanding of the landscape concept, necessary for the
formalisation of ecoagriculture, this study assessed the landscape perceptions and
understandings held by local people residing within a TFCA. We employed
participatory methods within the Mathenjwa Tribal Area (MTA), an area falling within
the Lubombo TFCA and identified as holding ecoagriculture potential. Results revealed
that local people perceive landscape as a function of subsistence utility. Local people
perceive land-use multifunctionality, necessary for the formalisation of ecoagriculture, but at a smaller scale than expected depending on both social and biophysical
interpretations. Landscape scale projects should incorporate local landscape
understandings. / Dissertation (MA)--University of Pretoria, 2013. / Geography, Geoinformatics and Meteorology / MA / Unrestricted
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Native legume species from the Northern Cape province of South Africa and their potential use as forage crops.Müller, Francuois L. January 2021 (has links)
Philosophiae Doctor - PhD / The lack of bioclimatically suitable forage species for livestock production in the water-limited agro-ecological areas of South Africa has resulted in significant feed shortages within these areas during the ongoing drought experienced within the country. This, in turn, has resulted in significant livestock mortalities leading to financial difficulties for the farmers and farming communities within these areas. Thus, many of the water-limited agro-ecological areas in South Africa have been declared disaster areas. These cyclic long-term droughts, as well as more common short-term droughts are expected to increase in frequency, duration and intensity under the predicted future bioclimatic conditions. Although there has been significant investment into the development of improved, better-adapted forage crops for these bioclimatically marginal agro-ecosystems, these efforts, to date, have largely been unsuccessful. Therefore, in this study, we propose to identify and evaluate species that are native to the water-limited South African agro-ecosystems and that can potentially be implemented in alternative fodder flow programs within these water-limited agro-ecological areas. / 2022
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An assessment of the potential for using gasification technologies for thermal applications in Uganda’s small-scale agro-industriesMutyaba, Job January 2014 (has links)
Energy is one of the biggest costs of production in industries and Small scale industries in Uganda are faced with a big burden due to the high energy costs they incur in their operations. Due to the high costs associated with electricity and fossil fuels, biomass energy continues to supply the bulk (81%) of industrial energy demands. However unsustainable harvesting of tradition biomass fuels (firewood and charcoal) is leading to depletion and causing a hike in prices of this important energy source. This study determined current thermal loads for 4 small scale industries, the costs of the fuels used, possible agro waste replacement options and economic comparisons of gasification using these fuel alternatives. Questionnaires, interviews and quantitative measurements of the various parameters were undertaken to establish current fuel usage and costs. Economic and emission reductions analysis were conducted using RETScreen energy planning tool. Results of indicated that the current combustion and heat transfer devices are very inefficient leading to intensive energy demands. Proposed gasifier systems of the range of 30 kW to 100kW fuel power, would cost between US$ 6,156.35 and US$20,371.20. It was further established that installing gasifiers and incorporating agro wastes in the fuel mix (60%) would greatly reduce expenditure on fuels with pay back periods ranging from 0.4 – 3 years. Risk analysis further showed that fuel costs and operations and maintenance would attract the highest risk to the net present value of each proposed gasifier installation. From these results, it was recommended that gasification coupled with use of agro wastes provides viable cheap alternative for small scale industrial thermal energy needs
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The Commodification of Bluefin Tuna: The Historical Transformation of the Mediterranean FisheryLongo, Stefano B., Clark, Brett 01 April 2012 (has links)
Employing a political-economic approach, we examine the Atlantic bluefin tuna fisheries in the Mediterranean. In doing so, we highlight historical transformations in fishing operations given the commodification of bluefin tuna and the growth imperative of capitalism. Fieldwork in Sicily and Sardinia, in-depth interviews, and primary and secondary data inform this analysis. Within the global agro-food system, traditional trap fisheries that operated for centuries have diminished. Industrialized fishing and tuna-ranching operations - that make use of high-tech, capital-intensive methods - have reorganized production, including the labour process, the capture of fish and the lifecycles of bluefin tuna. In an attempt to profit from the exploitation of the most prized fish in the world, capitalist fishing operations are harvesting bluefin tuna at a rate that exceeds the reproductive capabilities of the existing stock, which has had negative consequences for the traditional trap fishery and may lead to the collapse of this fishery. Modern capitalist social relations have destabilized an ecological system that has long been coupled with human systems within a few decades, with extensive socio-ecological consequences. Aquaculture, as a proposed solution, is a technological fix, which cannot resolve fundamental ecological contradictions.
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