Microalgae: The Basis of Mankind Sustainability

Microalgae were the basis of life into the planet, but only recently these microorganisms are exploited at a commercial scale. Thus, the production of pharmaceuticals, cosmetics, feed, and foods from microalgae is today a commercial reality increasing year by year. Additionally, microalgae have been proposed to be used to enhance the sustainability of existing industrial activities, as wastewater treatment and biofuel production. In this way, the utilization of microalgae at a large scale is considered a green revolution in the sustainability of mankind. This chapter is focused on reviewing the real contribution of microalgae to human activities. The last improvements of technologies and its uses, in addition to still existing bottlenecks for the massive exploitation of these microorganisms, are reviewed

Biostimulant potential of Scenedesmus obliquus grown in brewery wastewater

ABSTRACT: Microalgae are microorganisms with the capacity to contribute to the sustainable and healthy food production, in addition to wastewater treatment. The subject of this work was to determine the potential of Scenedesmus obliquus microalga grown in brewery wastewater to act as a plant biostimulant. The germination index of watercress seeds, as well as the auxin-like activity in mung bean and cucumber, and in the cytokinin-like activity in cucumber bioassays were used to evaluate the biostimulant potential. Several biomass processes were studied, such as centrifugation, ultrasonication and enzymatic hydrolysis, as well as the final concentration of microalgal extracts to determine their influence in the biostimulant activity of the Scenedesmus biomass. The results showed an increase of 40% on the germination index when using the biomass at 0.1 g/L, without any pre-treatment. For auxin-like activity, the best results (up to 60% with respect to control) were obtained at 0.5 g/L of biomass extract, after a combination of cell disruption, enzymatic hydrolysis and centrifugation. For cytokinin-like activity, the best results (up to 187.5% with respect to control) were achieved without cell disruption, after enzymatic hydrolysis and centrifugation at a biomass extract concentration of 2 g/L.info:eu-repo/semantics/publishedVersio

Utilization of centrate for the production of the marine microalgae Nannochloropsis gaditana

In this paper, the production of the microalga Nannochloropsis gaditana using centrate from the anaerobic digestion of treated urban wastewater is studied. For this, semicontinuous cultures were performed indoors at laboratory scale, under controlled conditions, supplying seawater with different centrate percentages from a real wastewater treatment plant as the culture medium. It was demonstrated that N. gaditana can be produced using solely centrate as the nutrient source but only at percentages below 50%. Above this level, inhibition is caused by an excess of ammonia, thus reducing productivity. In the 30-50% centrate range, biomass productivity was 0.4 g·l-1·day-1, equal to that measured when using Algal culture medium. Moreover, the biochemical composition of the biomass was also equal to that measured when using Algal culture medium, with the protein content in the 30-40%d.wt. range; whereas the lipid content ranged from 20 to 25%d.wt. Under these conditions, phosphorus depuration from the culture medium was in the 80-90% range while nitrogen depuration was only between 20 and 40%, indicating an excess of nitrogen in the centrate with respect to phosphorus. In spite of this phosphorus limitation, in the optimal centrate range (30-50% in the culture medium), the cells performed under optimal conditions, removing up to 35 mgN·l-1·day-1 and 5.7 mgP·l-1·day-1, with quantum yield values measuring 1.0-1.3 g·E-1. By supplying additional phosphorus, it was possible to enhance productivity and increase nitrate and phosphorus depuration to over 80%. The use of centrate is confirmed as a useful method for reducing microalgae production costs while also increasing process sustainability, especially when using biomass for bioenergy applications

Solar Drying of Greenhouse Crop Residues for Energy Valorization: Modeling and Determination of Optimal Conditions

Large amounts of crop residue are produced annually in areas such as Almeria (Spain). These residues have elevated moisture and ash contents, and are also very heterogeneous, which hinders their reutilization. With the aim of facilitating biomass utilization in energy recovery-related processes, a model for solar drying was developed. Experiments were performed inside a greenhouse with tomato and pepper residues, following two strategies (hung or stacked residues). The influence of temperature and relative humidity on the residues’ equilibrium moisture was also studied. The results were that a model allowed for determination of the equilibrium moisture as a function of ambient conditions (temperature and relative humidity), with the model’s characteristic parameters being different for each crop residue. Regarding the drying process, the results conform to first-order kinetics, with the values of the kinetic constants varying as a function of the crop residues and their arrangement. The variation in equilibrium moisture as a function of the annual variation in ambient conditions (temperature and relative humidity) in Almería means that it would only be possible to dry crop residues inside greenhouse below a moisture level of 0.43 kgwater/kgdrysolids (30% water content) from April to November

A new approach for detection and quantification of microalgae in industrial-scale microalgal cultures

In industrial-scale cultures, non-target microalgae compete with the desired species for nutrients and CO2, thus reducing the growth rate of the target species and the quality of the produced biomass. Microalgae identification is generally considered a complicated issue although, in the last few years, new molecular methods have helped to rectify this problem. Of the different techniques available, DNA barcoding has proven very useful in providing rapid, accurate and automatable species identification; in this work, it is used to assess the genomic identity of the microalga species Scenedesmus almeriensis, a common strain in industrial-scale cultures. Barcode markers rbcL and ITS1-5.8S-ITS2 were sequenced and the obtained genomic information was used to design a quantitative PCR assay to precisely quantify the S. almeriensis concentration in microalgal cultures of industrial interest. TaqMan chemistry was used to quantify down to 1 µg/L dry weight of S. almeriensis cells, as well as to detect the presence of other concentrated microalgae cultures. A simple direct PCR approach was also investigated to avoid classic DNA extraction and to reduce total experiment time to approximately 2 hours. The objective was to design strain-specific tools able to confirm and quantify the presence of different strains in any microalgae culture so as to achieve maximal productivity and quality of the produced biomass

Microalgae research worldwide

In this paper, worldwide research trends in the microalgae field are analyzed based on a bibliometric study. We have looked at the number of publications and their distribution, as well as the most relevant journals and keywords, to determine the evolution and latest tendencies in this field. The results confirm that this is a fast-growing area in terms of the number of publications. The most relevant journals on this subject are Bioresource Technology and Algal Research. Although the majority of papers come out of the USA, the most relevant institutions are actually located in China, France and Spain. The most frequently cited strains are Chlorella and Chlamydomonas. The main keywords that appear in over 1,000 articles are generally related to microalgae cultivation applications such as ‘biomass, biofuel, and lipids’ while others are related to the methodology; for instance, ‘bioreactor’. Of all the keywords, ‘biomass’ stands out, as it appears in almost 20% of publications. Bibliographic analysis confirms that Microalgae Biotechnology is a very active field, where scientific productivity has exponentially increased over recent years in tandem with industrial production. Therefore, expectations are high in this field for the near future

Consorcios y alianzas estratégicas en el ámbito de la investigación y la innovación: Presentación de casos y buenas prácticas

La importancia que actualmente poseen los consorcios y las alianzas estratégicas en el ámbito de la investigación y la innovación anda pareja a las dificultades que entrañan tanto su generación como su gestión diaria. Por ello, toda aproximación que se haga a estas significativas estructuras colaborativas ha de verse acompañada necesariamente por el relato de sus propios actores, donde se destaque la problemática que suscitan, desde el primer momento de su concepción. Precisamente a esta perspectiva práctica responde este e-book, fruto directo del conjunto de actividades que se han realizado durante el año 2021 y que fueron llevadas a cabo, a iniciativa, impulso y dirección por parte de la Fundació Parc Científic Universitat de València (FPCUV), las cuales se centraron en el análisis de un relevante conjunto de casos extraídos de la propia práctica, con la finalidad de advertir sobre los riesgos existentes y proporcionar un nutrido conjunto de buenas prácticas derivadas directamente de la valiosa experiencia atesorada desde distintos consorcios.PPC /2021/011The importance that consortia and strategic alliances currently have in the field of research and innovation goes hand in hand with the difficulties involved in both their generation and their daily management. For this reason, any approach made to these significant collaborative structures must necessarily be accompanied by the story of their own actors, where the problems they raise are highlighted, from the first moment of their conception. This e-book responds precisely to this practical perspective, the direct result of the set of activities that have been carried out during the year 2021 and that were carried out, at the initiative, impulse and direction of the University of Valencia Science Park Foundation (FPCUV), which focused on the analysis of a relevant set of cases extracted from the practice itself, in order to warn about the existing risks and provide a large set of good practices derived directly from the valuable experience accumulated from different consortia

Salud de los trabajadores

Actividad física y su relación con los factores de riesgo cardiovascular de carteros chilenosAnálisis de resultados: riesgos psicosociales en el trabajo Suceso-Istas 21 en Cesfam QuellónAusentismo laboral por enfermedades oftalmológicas, Chile 2009Brote de diarreas por norovirus, posterremoto-tsunami, Constitución, Región del MauleCalidad de vida en profesionales de la salud pública chilenaCaracterización del reposo laboral en personal del SSMN durante el primer semestre de 2010Concentración de nicotina en pelo en trabajadores no fumadores expuestos a humo de tabaco ambientalCondiciones de trabajo y bienestar/malestar docente en profesores de enseñanza media de SantiagoDisfunción auditiva inducida por exposición a xilenoErgonomía aplicada al estudio del síndrome de dolor lumbar en el trabajoEstimación de la frecuencia de factores de riesgo cardiovascular en trabajadores de una empresa mineraExposición a plaguicidas inhibidores de la acetilcolinesterasa en Colombia, 2006-2009Factores de riesgo y daños de salud en conductores de una empresa peruana de transporte terrestre, 2009Las consecuencias de la cultura en salud y seguridad ocupacional en una empresa mineraPercepción de cambios en la práctica médica y estrategias de afrontamientoPercepción de la calidad de vida en la Universidad del BiobíoPesos máximos aceptables para tareas de levantamiento manual de carga en población laboral femeninaRiesgo coronario en trabajadores mineros según la función de Framingham adaptada para la población chilenaTrastornos emocionales y riesgo cardiovascular en trabajadores de la salu

Mechanistic model for design, analysis, operation and control of microalgae cultures: Calibration and application to tubular photobioreactors

Closed photobioreactors (PBRs) are usually used for the production of high-value microalgae biomass at higher productivities than in open ponds. A large variety of different PBRs have been developed to optimize the biomass productivity and photosynthesis efficiency. At the same time mathematical models for PBRs are also increasing in popularity for design of new systems and for improving understanding of the complex processes occurring inside. The aim of the present study is to calibrate of the new mechanistic model for microalgae growth using experimental data from two different tubular photobioreactors. Hydrodynamic and light attenuation through the medium were added in the model to obtain a realistic representation of photobioreactor. Furthermore, the model was able to predict microalgae production under different climatic conditions and the oxygen accumulation throughout the photobioreactor

A review on the status of protein nutrition of Argentine penaeoid shrimp: Comparison and contrasts within the Penaeidae

Protein is the major and the most expensive ingredient in shrimp feeds, as well as a growth limiting nutrient. This paper reviews the results of investigations designed to understand the protein nutrition in the most abundant penaeoid species in the Argentine Sea, Pleoticus muelleri Bate, 1888 and Artemesia longinaris Bate, 1888. One of the main obstacles to culture these species is the inadequate knowledge of their nutritional requirements. The present review focuses on applied nutrition of protein, protein sources in feed, and apparent digestibility. Also considered are digestive proteinase activity in relation to developmental stages and molting cycle, amino acid requirements, and optimal protein levels measured by growth responses. These results are compared with those obtained for other penaeoid species. This review provides a better understanding of feeding preferences and the formulation of suitable feeds for shrimp, which is essential to optimize the use of ingredients and reduce feed costs.Pleoticus muelleri Bate, 1888 and Artemesia longinaris Bate, 1888. One of the main obstacles to culture these species is the inadequate knowledge of their nutritional requirements. The present review focuses on applied nutrition of protein, protein sources in feed, and apparent digestibility. Also considered are digestive proteinase activity in relation to developmental stages and molting cycle, amino acid requirements, and optimal protein levels measured by growth responses. These results are compared with those obtained for other penaeoid species. This review provides a better understanding of feeding preferences and the formulation of suitable feeds for shrimp, which is essential to optimize the use of ingredients and reduce feed costs.Fil: Fenucci, Jorge Lino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Díaz, Ana Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Acien Fernandez, Francisco Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin