Achieving healthy and profitable production through collective action? The case of vegetable farmers in the French West Indies.

Given the multiple challenges that agriculture faces, collective action is a potential pathway towards more sustainable agriculture. This article aims to contribute to the literature by assessing the extent to which collective action can meet the objective of both healthy and profitable production in the French West Indies. To do so, we call on the theory of collective action and emphasise the role of formal and informal collectives in achieving the objectives of improving income and implementing agroecological practices. We use original data collected in 2022 from 409 vegetable farmers in Martinique and Guadeloupe. We consider the interdependence between farmers' economic and environmental objectives through a simultaneous equations model. We characterise the diversity of collectives according to their degree of formalisation and to the adequacy between the objectives pursued by these collectives and the individual objectives of their members. Our results show that the achievement of an individual objective is fostered by its adequacy with the objective set by the collective and also, to a certain extent, by the degree of formalisation of this collective. It appears that achieving individual objectives is based on sharing common objectives as well as having collective rules. More particularly, we find that producer organisations - collectives considered to be the most formal - best meet the objectives of improving income and adopting agroecological practices. However, in the French West Indies, the instability of such collectives and the organisational deficiencies of the sector call into question their real long-term impact. These findings contribute to a better understanding of farmers' decision-making and provide relevant policy implications for supporting agricultural collectives in managing and federating producers towards achieving a more healthy and profitable production.

Biofilm Formation and Antimicrobial Resistance of Staphylococcus aureus and Streptococcus uberis Isolates from Bovine Mastitis.

This study aimed to assess (a) the biofilm producer ability and antimicrobial resistance profiles of Staphylococcus (Staph.) aureus and Streptococcus (Strep.) uberis isolated from cows with clinical mastitis (CM) and subclinical mastitis (SCM), and (b) the association between biofilm producer ability and antimicrobial resistance. We isolated a total of 197 Staph. aureus strains (SCM = 111, CM = 86) and 119 Strep. uberis strains (SCM = 15, CM = 104) from milk samples obtained from 316 cows distributed in 24 dairy herds. Biofilm-forming ability was assessed using the microplate method, while antimicrobial susceptibility was determined using the disk diffusion method against 13 antimicrobials. Among the isolates examined, 57.3% of Staph. aureus and 53.8% of Strep. uberis exhibited the ability to produce biofilm, which was categorized as strong, moderate, or weak. In terms of antimicrobial susceptibility, Staph. aureus isolates displayed resistance to penicillin (92.9%), ampicillin (50.8%), and tetracycline (52.7%). Conversely, Strep. uberis isolates exhibited resistance to penicillin (80.6%), oxacillin (80.6%), and tetracycline (37.8%). However, no significant correlation was found between antimicrobial resistance patterns and biofilm formation ability among the isolates.

Modeling the economic impact for Chile of an import ban on genetically modified maize.

We estimate producer and consumer surplus changes due to a possible GM maize import ban in Chile, which produces only non-GM grains for internal use. Without foreign non-GM sources, the ban's effect on domestic maize prices would be so significant as to induce Chile to switch from net exporter to net importer of animal products. Fixed factor owners in farm production would benefit significantly, although non-GM maize imports would moderate gains. Total social welfare measures would decline considerably, requiring large offsetting noneconomic benefits for a ban's political viability. Without non-GM imports, internal maize prices would likely eliminate domestic animal product industries; with possible imports, industries and final consumers would suffer, but much less. Currently, the country is a net importer of grain and a net exporter of pork and poultry, and so most welfare losses on the demand side of the market for maize would be in terms of the economic rents generated by the pork and poultry sectors. International competition would protect final consumers to the extent that animal product imports based on GM feed were permitted.

Eco-management of end-of-life tires: Advances and challenges for the Ecuadorian case.

The aim of this research is to analyse the performance of the extended producer responsibility model for the management of end-of-life tires (ELTs) in Ecuador that has been implemented since 2013. For this research, we conducted case studies of, and subsequently, a comparative analysis between, the ELT management system in Ecuador with respect to the ELT management models in Colombia and Brazil. Our findings show that although the programme implementation represented a significant advance in Ecuador's waste management system there are important challenges that should be considered in future adaptations of the programme. Among the measures that can be adopted to improve the ELT management system are the consolidation and stimulation of the market for products made from ELT waste; promotion of other productive sectors linked to the creation of new products and sectors that generate complementary products; enhancement of the generation, socialization and access to knowledge of the waste by-products for micro-, small- and medium-sized enterprises; increase the tire consumer fee, known as 'Ecovalor' and improvement of the quality and availability of information and indicators regarding ELT management. In this sense, the experiences of Colombia and Brazil show important lessons for the Ecuadorian case.

Municipal solid waste management instruments that influence the use of the refuse as fuel in developing countries: A critical review.

Landfills are the destination of most of the refuse generated whereas composting, material recycling, and Waste-to-Energy (WtE) technologies are not commonly employed in developing countries. However, the destination for energy purposes could be supplied with this refuse, improving the viability of energy use. Thus, this article raises some questions to identify aspects that could encourage its use as refuse-derived fuel (RDF) in these countries. Among them, does environmental education affect the municipal solid waste (MSW) source separation with emphasis on a destination? Can selective collection and extended producer responsibility (EPR) affect the MSW for energy recovery? Is there competition between the recycling market and the energy market for RDF? A systematic review of the literature was conducted to gather data and provide answers to such questions. This enabled to observe that EPR, selective collect expansion and source separation influence the quantity and quality of waste sent for energy use. Both internal and external factors impact on source separation. Additionally, there is evidence to support that despite several studies showing their technical, economic, environmental and social viability, the methods of energy usage of the refuse still need to improve their deployment in developing countries. In addition to identifying the main research gaps to be filled in future studies, the article also identified the instruments of MSW management that are to be applied in developing countries to divert recyclable and organic waste from landfill.

Evaluation of the BD Phoenix Carbapenemase-Producing Organism Panels for the Detection of Carbapenemase Producers in Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa.

The classification of carbapenemases can help guide therapy. The present study evaluated the performance of the CPO detection test, included in the BD Phoenix™ NMIC-501 panel for the detection and classification of carbapenemases on the representative molecularly characterized strains collection from Mexico. Carbapenem non-susceptible isolates collected in Mexico were included. The clinical isolates (n = 484) comprised Klebsiella pneumoniae (n = 154), Escherichia coli (n = 150), and P. aeruginosa (n = 180). BD Phoenix CPO NMIC-504 and NMIC-501 panels were used for the identification of species, antimicrobial susceptibility tests, and detection of CPOs. For the detection of carbapenemase-encoding genes, E. coli and K. pneumoniae were evaluated using PCR assays for blaNDM-1, blaKPC, blaVIM, blaIMP, and blaOXA-48-like. For P. aeruginosa, blaVIM, blaIMP, and blaGES were detected using PCR. Regarding E. coli, the CPO panels had a sensitivity of 70% and specificity of 83.33% for the detection of a class B carbapenemase (blaNDM in the molecular test). Regarding K. pneumoniae, the panels had a sensitivity of 75% and specificity of 100% for the detection of a class A carbapenemase (blaKPC in the molecular test). The Phoenix NMIC-501 panels are reliable for detecting class B carbapenemases in E. coli. The carbapenemase classification in K. pneumoniae for class A carbapenemases has a high specificity and PPV; thus, a positive result is of high value.

To produce or not to produce? Contrasting the effect of substance abuse in social decision-making situations.

Substance use disorders (SUD) have been related to high criminal justice costs, expensive healthcare, social impairment, and decision-making deficits. In non-social decision-making tasks, people with SUD tend to take more risks and choose small immediate rewards than controls. However, few studies have explored how people with SUD behave in social decision-making situations where the resources and profits depend directly on participants' real-time interaction, i.e., social foraging situations. To fulfill this gap, we developed a real-time interaction task to (a) compare the proportion of producers (individuals who tend to search for food sources) and scroungers (individuals who tend to steal or join previously discovered food sources) among participants with SUD and controls with respect to the optimal behavior predicted by the Rate Maximization Model, and (b) explore the relationship between social foraging strategies, prosocial behavior, and impulsivity. Here participants with SUD (n = 20) and a non-user control group (n = 20) were exposed to the Guaymas Foraging task (GFT), the Social Discounting task (SD), and the Delay Discounting task (DD). We found that participants in the control group tended to produce more and obtain higher profits in contrast to substance abuser groups. Additionally, SD and DD rates were higher for scroungers than producers regardless of the group. Our results suggest that producers tend to be more altruistic and less impulsive than scroungers. Knowing more about social strategies and producers' characteristics could help develop substance abuse prevention programs.

Caracterização dos sistemas de criação de caprinos e ovinos da Ilha de São Luís no estado do Maranhão, Brasil / Characterization of goat and sheep breeding systems at São Luis Island in the state of Maranhão, Brazil

Objetivou-se descrever o perfil dos sistemas de criação de caprinos e ovinos da Ilha de São Luís no estado do Maranhão. Para isso, realizou-se um estudo descritivo, exploratório e quali-quantitativo com 80 produtores rurais selecionados pela técnica Snowball, no período de fevereiro a abril de 2021. Em relação ao perfil do produtor rural, verificou-se predominância do gênero masculino (93,8%), apresentando faixa etária entre 25 a 60 anos (86,2%). A maioria dos produtores apresentavam ensino médio completo (23,8%) ou ensino superior completo (23,8%) e 88,8% dos produtores não estavam vinculados a organizações coletivas, associações, cooperativas ou sindicatos. Nas propriedades rurais o sistema de criação predominante era o semi-extensivo (73,8%) com presença de apriscos (76,2%) e as criações eram consorciadas com caprinos e ovinos (58,8%). A principal causa de morte nos animais verificada foi a verminose (58,8%). Conclui-se que se faz necessário o estabelecimento de medidas de estímulo às criações na Ilha de São Luís por meio de políticas públicas voltadas aos produtores locais, requerendo, sobretudo, assistência técnica, orientações zootécnicas, educação sanitária e acesso ao crédito, para, assim, deixar de ser apenas uma atividade de subsistência e passar a gerar maiores rendas para as famílias produtoras.

The objective of this research was to describe the profile of the goat and sheep rearing systems on the Island of São Luís in the state of Maranhão. For this, a descriptive, exploratory and qualitative-quantitative study was carried out with 80 rural producers selected by the Snowball technique, from February to April 2021. Regarding the profile of the rural producer, there was a predominance of males (93.8%), aging between 25 and 60 years (86.2%). Most producers had completed high school (23.8%) or higher education (23.8%) and 88.8% were not members of collective organizations, associations, cooperatives or unions. In rural properties, the predominant rearing system was semi-extensive (73.8%) with the presence of sheepfolds (76.2%) and mutual goats and sheep farming (58.8%). The main cause of death of animals was warm infections (58.8%). In conclusion, it is necessary to establish measures to support sheep and goat farming on the Island of São Luís through public policies focused on local producers, which require, above all, technical assistance, zootechnical guidelines, health education and access to credit in order to the farms stop being just a subsistence activity and start generating higher incomes for producing families.

Labour costs on the vegetables: a research on the location effect on salaries in Jiangsu Province, China / Custos trabalhistas nas hortaliças: uma pesquisa sobre o efeito da localização nos salários na província de Jiangsu, China

In this study, the labour requirement and labour cost of common vegetable cultivation were investigated to help agricultural enterprises and family farms establishing reasonable "working hour" management systems in Jiangsu Province. The labour requirement of each step of three type of producers, agriculture enterprises, family farms, and private vegetable growers, in three regions in Jiangsu Province, named north, middle and south Jiangsu, was investigated by on-site observation or questionnaire survey during 2018 and 2019. The labour cost of each step and each vegetable was counted according to the labour requirement and the salary level. The results indicated that "residue cleaning", "soil preparation and bedding", "plant regulation", "auxin treatment of tomato flowers" and "hand pollination" accounted for higher proportions of labour cost amongst the entire vegetable culture process. No significant differences in the labour requirements of the investigated vegetables were reported amongst three regions in Jiangsu Province. However, the order of labour cost is south Jiangsu > north Jiangsu > middle Jiangsu, due to the salary difference amongst three regions. Watermelon, broccoli and chive are more suitable for growing by agricultural enterprises since they have relatively low unit labour and high prices. We established a method to calculate and analyze labour requirement and cost of vegetable production in Jiangsu Province, which also may be instructive for other regions. In addition, our results provided useful data for various vegetable producers to improve their labour management.

Neste estudo, a necessidade de trabalho e o custo do cultivo comum de vegetais foram investigados para ajudar as empresas agrícolas e fazendas familiares a estabelecer sistemas de gestão de "horas de trabalho" razoáveis ​​na província de Jiangsu. A necessidade de trabalho de cada etapa de três tipos de produtores, empresas agrícolas, fazendas familiares e horticultores privados, em três regiões da província de Jiangsu, denominadas norte, centro e sul de Jiangsu, foi investigada por observação no local ou pesquisa por questionário durante 2018 e 2019. O custo da mão de obra de cada etapa e de cada hortaliça foi contabilizado de acordo com a necessidade de mão de obra e o nível salarial. Os resultados indicaram que "limpeza de resíduos", "preparo de solo e cama", "regulação de plantas", "tratamento com auxina de flores de tomate" e "polinização manual" foram responsáveis por maiores proporções de custo de mão de obra em todo o processo de cultivo de vegetais. Nenhuma diferença significativa nas necessidades de trabalho dos vegetais investigados foi encontrada entre as três regiões da província de Jiangsu. No entanto, a ordem do custo da mão-de-obra é sul de Jiangsu> norte de Jiangsu> meio de Jiangsu, devido à diferença salarial entre as três regiões. Melancia, brócolis e cebolinha são mais adequados para o cultivo por empresas agrícolas, uma vez que têm uma unidade de trabalho relativamente baixa e preços altos. Estabelecemos um método para calcular e analisar a necessidade de mão de obra e o custo da produção de vegetais na província de Jiangsu, que também pode ser empregado para outras regiões. Além disso, nossos resultados forneceram dados úteis para vários produtores de vegetais melhorarem sua gestão de mão de obra.

Stakeholders' participation in environmental regulation: A case study of the sectoral agreement of packaging reverse logistics in Brazil.

This paper discusses the role of stakeholders' participation in decision-making of waste policies, exploring the case of the sectoral agreement (SA) of packaging in Brazil. This case represents a robust step to introduce circular economy for packaging in Brazil and Latin America. Since the enactment of the Brazilian National Solid Waste Policy in 2010, a series of agreements were created to introduce an alternative model of extended producer responsibility in the country. This historical analysis evaluates the decision-making and the outcomes of its participatory process. Three qualitative research methods were applied: 76 interviews with stakeholders at the three levels of governance; observation of five events during the negotiation process and analysis of government documents. The results show that stakeholders' participation was crucial throughout the policy design, contributing directly and indirectly to the outcomes of the SA, with knowledge exchange, creation of networks and by pressuring solid waste management issue onto the government's agenda. However, the participatory process is not straightforward, and during the agreement process, some advancements seem to be jeopardised, with risk of participation being exploited to legitimise political interests. At the end, research points out that participation needs to be promoted and expanded throughout all the stages of the policy cycle, bringing together also other stakeholders such as local governments and civil society.

Conditioning factors to market fruits and vegetables from family farms to supermarket supply chains / Fatores condicionantes à comercialização de frutas, legumes e verduras da agricultura familiar em cadeias de suprimentos de supermercados

Globally, increasing number of fruits and vegetables are being consumed to maintain healthy eating habits. Family farming plays a crucial role in fruits and vegetables production; products are marketed in supply chains, which are increasingly demanding, diversified, and complex. Participation of the family farms in each of these supply chains is subject to their ability to meet the increasingly strict participation criteria. In this context, this study identified the main factors that affect the participation of the family farmers in the supermarket supply chains for fresh fruits and vegetables. A systematic literature review was conducted, covering the period from 2005 to 2019. Results indicated eleven variables that affect the participation of the fruits and vegetables family farms in the supermarket supply chains. These variables were grouped in an analytical framework, which comprised four factors: characteristics of the producer, characteristics of the farm, institutional aspects, and available infrastructure. This framework is useful for the development and implementation of the public and private policies for successful participation of fruits and vegetables family farmers in supermarket supply chains.(AU)

Preocupações ambientais e a busca por uma alimentação saudável têm levado ao aumento mundial de consumo de frutas, legumes e verduras. A agricultura familiar é um segmento muito importante na produção de frutas, legumes e verduras, sendo os seus produtos comercializados em cadeias de suprimentos crescentemente mais exigentes, complexas e diversificadas. A participação de produtores familiares em cada uma destas cadeias de suprimentos está submetida a capacidade deles atenderem critérios de inserção cada vez mais estritos.As cadeias de suprimentos de frutas,legumes e verduras que abastecem os supermercados não fogem a esta situação.Neste contexto, este artigo identificou os principais fatores que condicionam a inserção dos agricultores familiares nas cadeias de suprimentos de frutas, legumes e verduras dos supermercados.Para tanto, foi realizada uma revisão sistemática da literatura num período compreendido entre 2005 e 2019. Os resultados encontrados mostraram que existem onze variáveis que condicionam a inserção da agricultura familiar em cadeias supermercadistas de frutas, legumes e verduras. Estas variáveis foram agrupadas em um framework analítico composto por quatro fatores: características do produtor e da propriedade, aspectos institucionais e infraestrutura. Este framework é útil ao desenvolvimento e implementação de políticas públicas e privadas voltadas à inserção exitosa da produção de frutas, legumes e verduras de agricultores familiares nas cadeias de suprimentos de supermercados.(AU)

Conditioning factors to market fruits and vegetables from family farms to supermarket supply chains / Fatores condicionantes à comercialização de frutas, legumes e verduras da agricultura familiar em cadeias de suprimentos de supermercados

ABSTRACT: Globally, increasing number of fruits and vegetables are being consumed to maintain healthy eating habits. Family farming plays a crucial role in fruits and vegetables production; products are marketed in supply chains, which are increasingly demanding, diversified, and complex. Participation of the family farms in each of these supply chains is subject to their ability to meet the increasingly strict participation criteria. In this context, this study identified the main factors that affect the participation of the family farmers in the supermarket supply chains for fresh fruits and vegetables. A systematic literature review was conducted, covering the period from 2005 to 2019. Results indicated eleven variables that affect the participation of the fruits and vegetables family farms in the supermarket supply chains. These variables were grouped in an analytical framework, which comprised four factors: characteristics of the producer, characteristics of the farm, institutional aspects, and available infrastructure. This framework is useful for the development and implementation of the public and private policies for successful participation of fruits and vegetables family farmers in supermarket supply chains.

RESUMO: Preocupações ambientais e a busca por uma alimentação saudável têm levado ao aumento mundial de consumo de frutas, legumes e verduras. A agricultura familiar é um segmento muito importante na produção de frutas, legumes e verduras, sendo os seus produtos comercializados em cadeias de suprimentos crescentemente mais exigentes, complexas e diversificadas. A participação de produtores familiares em cada uma destas cadeias de suprimentos está submetida a capacidade deles atenderem critérios de inserção cada vez mais estritos.As cadeias de suprimentos de frutas,legumes e verduras que abastecem os supermercados não fogem a esta situação.Neste contexto, este artigo identificou os principais fatores que condicionam a inserção dos agricultores familiares nas cadeias de suprimentos de frutas, legumes e verduras dos supermercados.Para tanto, foi realizada uma revisão sistemática da literatura num período compreendido entre 2005 e 2019. Os resultados encontrados mostraram que existem onze variáveis que condicionam a inserção da agricultura familiar em cadeias supermercadistas de frutas, legumes e verduras. Estas variáveis foram agrupadas em um framework analítico composto por quatro fatores: características do produtor e da propriedade, aspectos institucionais e infraestrutura. Este framework é útil ao desenvolvimento e implementação de políticas públicas e privadas voltadas à inserção exitosa da produção de frutas, legumes e verduras de agricultores familiares nas cadeias de suprimentos de supermercados.

Technological indicators and productive performance of dairy cattle farming in the city of Rondon do Pará, state of Pará, Brazilian Amazon / Indicadores tecnológicos e desempenho produtivo da pecuária leiteira bovina no município de Rondon do Pará, Amazônia Brasileira

The objective of this study was to evaluate the technological level and productive performance of the milk producing units of the municipality of Rondon do Pará in the state of Pará. Data were collected through interviews with questionnaires, conducted at 55 dairy farms, which accounted for 43.3% of the milked cows in the municipality. The factors that characterize the systems of bovine milk production were estimated by means of factorial analysis using 12 variables representative of the production units surveyed. Five factors were extracted: F1 = size of the enterprise; F2 = environment and nutrition; F3 = technical assistance and herd management; F4 = animal health; F5 = schooling. From the scores associated with each factor, the index for productive performance of dairy cattle (DFPI) was calculated. The properties were classified into three levels of productive performance, including two considered to have a high level of DFPI, 16 with intermediate productive performance and 37 considered to have a low level of DFPI. There is a need to adopt technologies that promote the productive performance of dairy cattle in Rondon do Pará, as well as enable adaptation to socio-environmental public policies, with the aim of strengthening sustainable rural production through strategic actions that facilitate an increased technological level in farming systems production.

Avalia-se o nível tecnológico e o desempenho produtivo das unidades produtoras de leite do município de Rondon do Pará, estado do Pará. Os dados foram coletados a partir de entrevistas, com utilização de questionários, realizadas em 55 propriedades leiteiras, que juntas representam 43,3% do plantel de vacas ordenhadas do município. Os fatores que caracterizam os sistemas de produção de leite bovino foram estimados por meio de análise fatorial, utilizando 12 variáveis representativas das unidades de produção pesquisadas. Foram extraídos cinco fatores: F1 = tamanho do empreendimento; F2 = meio ambiente e nutrição; F3 = assistência técnica e manejo do rebanho; F4 = sanidade animal; e F5 = escolaridade. A partir dos escores associados a cada fator foi calculado o índice de desempenho produtivo da pecuária leiteira (IDPL). As propriedades foram classificadas em três níveis de desempenho produtivo, entre elas, duas consideradas com nível alto de IDPL, 16 com desempenho produtivo intermediário e 37 consideradas de nível baixo. Há necessidade da adoção de tecnologias para promover o desempenho produtivo da pecuária leiteira de Rondon do Pará, bem como possibilitar adequação às políticas públicas socioambientais, visando fortalecer a produção rural sustentável, por meio de ações estratégicas que viabilizem o aumento do nível tecnológico dos sistemas de produção.

Technological indicators and productive performance of dairy cattle farming in the city of Rondon do Pará, state of Pará, Brazilian Amazon / Indicadores tecnológicos e desempenho produtivo da pecuária leiteira bovina no município de Rondon do Pará, Amazônia Brasileira

The objective of this study was to evaluate the technological level and productive performance of the milk producing units of the municipality of Rondon do Pará in the state of Pará. Data were collected through interviews with questionnaires, conducted at 55 dairy farms, which accounted for 43.3% of the milked cows in the municipality. The factors that characterize the systems of bovine milk production were estimated by means of factorial analysis using 12 variables representative of the production units surveyed. Five factors were extracted: F1 = size of the enterprise; F2 = environment and nutrition; F3 = technical assistance and herd management; F4 = animal health; F5 = schooling. From the scores associated with each factor, the index for productive performance of dairy cattle (DFPI) was calculated. The properties were classified into three levels of productive performance, including two considered to have a high level of DFPI, 16 with intermediate productive performance and 37 considered to have a low level of DFPI. There is a need to adopt technologies that promote the productive performance of dairy cattle in Rondon do Pará, as well as enable adaptation to socio-environmental public policies, with the aim of strengthening sustainable rural production through strategic actions that facilitate an increased technological level in farming systems production.(AU)

Avalia-se o nível tecnológico e o desempenho produtivo das unidades produtoras de leite do município de Rondon do Pará, estado do Pará. Os dados foram coletados a partir de entrevistas, com utilização de questionários, realizadas em 55 propriedades leiteiras, que juntas representam 43,3% do plantel de vacas ordenhadas do município. Os fatores que caracterizam os sistemas de produção de leite bovino foram estimados por meio de análise fatorial, utilizando 12 variáveis representativas das unidades de produção pesquisadas. Foram extraídos cinco fatores: F1 = tamanho do empreendimento; F2 = meio ambiente e nutrição; F3 = assistência técnica e manejo do rebanho; F4 = sanidade animal; e F5 = escolaridade. A partir dos escores associados a cada fator foi calculado o índice de desempenho produtivo da pecuária leiteira (IDPL). As propriedades foram classificadas em três níveis de desempenho produtivo, entre elas, duas consideradas com nível alto de IDPL, 16 com desempenho produtivo intermediário e 37 consideradas de nível baixo. Há necessidade da adoção de tecnologias para promover o desempenho produtivo da pecuária leiteira de Rondon do Pará, bem como possibilitar adequação às políticas públicas socioambientais, visando fortalecer a produção rural sustentável, por meio de ações estratégicas que viabilizem o aumento do nível tecnológico dos sistemas de produção.(AU)

Betaine supplementation improved L-threonine fermentation of Escherichia coli THRD by upregulating zwf (glucose-6-phosphate dehydrogenase) expression

BACKGROUND: The supplementation of betaine, an osmoprotective compatible solute, in the cultivation media has been widely used to protect bacterial cells. To explore the effects of betaine addition on industrial fermentation, Escherichia coli THRD, an L-threonine producer, was used to examine the production of L-threonine with betaine supplementation and the underlying mechanism through which betaine functions was investigated. RESULTS: Betaine supplementation in the medium of E. coli THRD significantly improved L-threonine fermentation parameters. The transcription of zwf and corresponding enzyme activity of glucose-6-phosphate dehydrogenase were significantly promoted by betaine addition, which contributed to an enhanced expression of zwf that provided more nicotinamide adenine dinucleotide phosphate (NADPH) for L-threonine synthesis. In addition, as a result of the betaine addition, the betaine-stimulated expression of enhanced green fluorescent protein (eGFP) under the zwf promoter within a plasmid-based cassette proved to be a transcription-level response of zwf. Finally, the promoter of the phosphoenolpyruvate carboxylase gene ppc in THRD was replaced with that of zwf, while L-threonine fermentation of the new strain was promoted by betaine addition. Conclusions: We reveal a novel mode of betaine that facilitates the microbial production of useful compounds. Betaine supplementation upregulates the expression of zwf and increases the NADPH synthesis, which may be beneficial for the cell growth and thereby promote the production of L-threonine. This finding might be useful for the production of NADPH-dependent amino acids and derivatives in E. coli THRD or other E. coli strains.

Fermentation of yam (Dioscorea spp. L.) by indigenous phytase-producing lactic acid bacteria strains.

The use of lactic bacteria in the development of functional foods has increased in recent years. In addition to their probiotic characteristics, they can ferment a variety of substrates, such as cereals, roots, and tubers. Phytase producer lactic acid bacteria strains and their behavior during the fermentation process of yam-based food were studied. Leuconostoc lactis CCMA 0415, Lactobacillus plantarum CCMA 0744, and Lactobacillus fermentum CCMA 0745 were selected due to phytase production, pH reduction, and growth during 24 h of fermentation. Oxalate activity was not detected in all assays, suggesting its concentration was reduced due to the bleaching process. Among the selected strains, L. lactis CCMA 0415 appeared to be a promising strain in yam-based fermentations because it maintained a cell viability above 8 log CFU/mL and did not reduce diosgenin concentrations (around 8.0 µg/mL) after fermentation for 24 h, thereby, generating a potentially functional yam food. Furthermore, this strain promoted the decrease of pH value from 6.1 to 3.8 and produced 8.1 g/L lactic acid, at 6 h of fermentation. The L. lactis CCMA 0415 was reported as a starter culture in fermented products based on cereals, roots, and tubers.

Type C feruloyl esterase from Aspergillus ochraceus: a butanol specific biocatalyst for the synthesis of hydroxycinnamates in a ternary solvent system

Background: Aspergillus ochraceus was isolated from coffee pulp and selected as an interesting hydroxycinnamoyl esterase strain producer, using an activity microplate high-throughput screening method. In this work, we purified and characterized a new type C A. ochraceus feruloyl esterase (AocFaeC), which synthesized specifically butyl hydroxycinnamates in a ternary solvent system. Results: AocFaeC was produced by solid state fermentation, reaching its maximal activity (1.1 U/g) after 48 h of culture. After purification, the monomeric protein (34 kDa) showed a specific activity of 57.9 U/mg towards methyl ferulate. AocFaeC biochemical characterization confirmed its identity as a type C feruloyl esterase and suggested the presence of a catalytic serine in the active site. Its maximum hydrolytic activity was achieved at 40°C and pH 6.5 and increased by 109 and 77% with Ca2+ and Mg2+, but decreased by 90 and 45% with Hg2+ and Cu2+, respectively. The initial butyl ferulate synthesis rate increased from 0.8 to 23.7 nmol/min after transesterification condition improvement, using an isooctane:butanol:water ternary solvent system, surprisingly the synthesis activity using other alcohols was negligible. At these conditions, the synthesis specific activities for butyl p-coumarate, sinapinate, ferulate, and caffeate were 87.3, 97.6, 168.2, and 234 U/µmol, respectively. Remarkably, AocFaeC showed 5 folds higher butyl caffeate synthesis rate compared to type B Aspergillus niger feruloyl esterase, a well-known enzyme for its elevated activity towards caffeic acid esters. Conclusions: Type C feruloyl esterase from A. ochraceus is a butanol specific biocatalyst for the synthesis of hydroxycinnamates in a ternary solvent system

In vivo assay to identify bacteria with ß-glucosidase activity

Background: ß-Glucosidase assay is performed with purified or semipurified enzymes extracted from cell lysis. However, in screening studies, to find bacteria with ß-glucosidase activity among many tested bacteria, a fast method without cell lysis is desirable. In that objective, we report an in vivo ß-glucosidase assay as a fast method to find a ß-glucosidase producer strain. Results: The method consists in growing the strains for testing in a medium supplemented with the artificial substrate p-nitrophenyl-ß-glucopyranoside (pNPG). The presence of ß-glucosidases converts the substrate to p-nitrophenol (pNP), a molecule that can be easily measured in the supernatant spectrophotometrically at 405 nm. The assay was evaluated using two Bifidobacterium strains: Bifidobacterium longum B7254 strain that lacks ß-glucosidase activity and Bifidobacterium pseudocatenulatum B7003 strain that shows ß-glucosidase activity. The addition of sodium carbonate during pNP measurement increases the sensitivity of pNP detection and avoids the masking of absorbance by the culture medium. Furthermore, we show that pNP is a stable enzymatic product, not metabolized by bacteria, but with an inhibitory effect on cell growth. The ß-glucosidase activity was measured as units of enzyme per gram per minute per dry cell weight. This method also allowed the identification of Lactobacillus strains with higher ß-glucosidase activity among several lactobacillus species. Conclusion: This in vivo ß-glucosidase assay can be used as an enzymatic test on living cells without cell disruption. The method is simple, quantitative, and recommended, especially in studies screening for bacteria not only with ß-glucosidase activity but also with high ß-glucosidase activity.

Administración previa de antibiótico como factor asociado con infección urinaria por E. coli productora de BLEE de origen comunitario en pacientes diabéticos / Previous administration of antibiotic as factor related to urinary infection due to E. coli producers of ESBL of community origin in diabetic patients

Resumen ANTECEDENTES: las infecciones urinarias causadas por bacilos gramnegativos productores de betalactamasas de espectro extendido (BLEE) constituyen un problema mundial de salud pública. OBJETIVO: determinar si existe relación entre el tratamiento antibiótico previo y el desarrollo de E. coli BLEE al ingreso en pacientes con diabetes mellitus tipo 2. MATERIAL Y MÉTODO: estudio piloto de tipo transversal, analítico, en el que se revisaron los casos de infección de vías urinarias en pacientes diabéticos atendidos en el Nuevo Sanatorio Durango. Se compararon dos grupos según el resultado del urocultivo de ingreso. Se recolectaron datos tomando en cuenta el antecedente de tratamiento antibiótico, cifra de hemoglobina glucosilada (Hb1Ac), antecedente de hospitalización, si había antecedente de catéter urinario (sonda Foley) y diagnóstico de enfermedad renal crónica. RESULTADOS: se incluyeron 103 pacientes: 49 con E. coli y 54 con E. coli BLEE. Se encontró mayor asociación con infecciones urinarias productoras de BLEE en individuos de 68 ± 14.04 años en comparación con la edad de 49 ± 12 años en los sujetos con infecciones urinarias no productoras de BLEE. Se calculó razón de momios para cada uno de los rubros, se encontró asociación estadísticamente significativa por medio de X2 (p<0.05) calculando una razón de momios de 10.2 para el antecedente de administración de antibiótico y de 2.97 para el diagnóstico de enfermedad renal crónica y para el aislamiento de E. coli productora de BLEE. CONCLUSIÓN: existe asociación de la administración previa de tratamiento antibiótico y la existencia de enfermedad renal crónica con el aislamiento E. coli BLEE en infecciones adquiridas en la comunidad en pacientes diabéticos.

Abstract BACKGROUND: Urinary tract infections caused by gram-negative bacilli producers of extended-spectrum beta-lactamases (ESBL) are a global public health problem. MATERIAL AND METHOD: An analytical, cross-sectional, pilot study was carried out in Nuevo Sanatorio Durango, Mexico City, in which the cases of urinary tract infection in diabetic patients were reviewed. Two groups were compared depending on the result of the urinary culture. Data were collected taking into account the antecedent of antibiotic treatment, glycosylated hemoglobin (Hb1Ac), history of hospitalization, history of urinary catheter (Foley catheter) and diagnosis of chronic kidney disease. RESULTS: There were included 103 patients, divided according to the result of the urinary culture: E. coli (n = 49) and E. coli ESBL (n = 54). We found a greater association with ESBL-producing urinary tract infections in individuals aged 68 ± 14.04 years. We calculated odds ratios for each of the items, finding a statistically significant association by means of X2 test (p < 0.05), calculating an OR of 10.2 with the antecedent of antibiotic use and a OR of 2.97 with the diagnosis of chronic kidney disease, when there was isolation of E. coli producing ESBL. CONCLUSION: There is an association between the use of antibiotic treatment and the presence of chronic kidney disease with E. coli ESBL isolation in community-acquired infections in diabetic patients.

Dry matter digestibility and metabolizable energy of crude glycerines originated from palm oil using fed rooster assay / Digestibilidade da matéria seca e energia metabolizável da glicerina bruta originada a partir de óleo de palma usando ensaio de alimentação forçada com galos

A study was conducted to determine the dry matter digestibility, gross energy (GE), the nitrogen-corrected apparent metabolizable energy (AMEn), and the nitrogen-corrected true metabolizable energy (TMEn) of two crude glycerine from two different sources. The first crude glycerine (CG1) was from a large scale biodiesel producer with high content of glycerol (89.49%) and low content of crude fat (1.73%), meanwhile the second crude glycerine (CG2) was from a medium scale biodiesel producer with lower content of glycerol than CG1 (38.36%) and high content of crude fat (23.63%). Fed rooster assay based on Sibbald (1976) was used in the experiment. The experimental feed consisted of ground corn and three levels of crude glycerine (0, 10, and 20%). Twenty four Hisex brown roosters were housed in metabolic cages. Roosters were force fed with 30 g experimental feed, after 24 hours of fasting. Excreta collection was performed for two days while the roosters were fasting again. The content values of GE, AMEn, and TMEn of CG1 were 4065.18, 2926.59, and 3068.73 kcal kg-1 and for CG2 were 5928.09, 4010.11, and 4054.52 kcal kg, respectively.

O presente estudo foi realizado para determinar a digestibilidade da matéria seca, energia bruta (EB), energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) e energia metabolizável verdadeira corrigida pelo balanço de nitrogênio (EMVn) de glicerinas brutas de duas diferentes fontes. A primeira glicerina bruta (GB1) foi obtida de um produtor de biodiesel de grande escala contendo alto teor de glicerol (89,49%) e baixo teor de gordura bruta (1,73%), enquanto a segunda glicerina bruta (GB2) era de um produtor de biodiesel de média escala com menor conteúdo de glicerol do que GB1 (38,36%) e alto teor de gordura bruta (23,63%). O ensaio de alimentação forçada com galos baseado em Sibbald (1976) foi utilizado no experimento. A ração experimental foi composta de milho moído e três níveis de glicerina bruta (0, 10 e 20%). Vinte e quatro galos Hisex brown foram alojados em gaiolas metabólicas. Os galos foram alimentados a força com 30 g da ração experimental após jejum de 24 horas. A coleta de excretas foi realizada durante dois dias enquanto os galos permaneceram novamente em jejum. Os teores de EB, EMAn e EMVn de GB1 foram 4065,18, 2926,59 e 3068,73 kcal kg-1 para GB2 foram 5928,09, 4010,11 e 4054,52 kcal kg-1, respectivamente.