Producción de Compuestos Orgánicos de Valor Comercial a partir de la Biomasa Microalgal de Scenedesmus Dimorphus

Las microalgas son una prometedora fuente de compuestos orgánicos de valor comercial, ya que su cultivo se puede integrar con el aprovechamiento de corrientes residuales industriales, potenciando tanto la sustentabilidad como la rentabilidad de los procesos productivos.En este trabajo se estudió el rendimiento de extracciones secuenciales, con solventes n- hexano, etanol y acetona, de la biomasa de Scenedesmus dimorphus, cultivada en condiciones control y de estrés nutricional. El contenido lipídico fue de 162,6 mg/g y 265,8 mg/g respectivamente. Se observa que, sometido a falta de nutrientes, el cultivo produce una acumulación no solamente de lípidos (aumento de 344% p/p), sino de carbohidratos, astaxantina y sus ésteres. Los resultados muestran que a partir de cultivos de S. dimorphus es posible obtener distintos metabolitos orgánicos de interés, con métodos y solventes de extendido uso industrial, que no son los que frecuentemente se encuentran en la bibliografía de estudios microalgales

Algae for Biofuels and Energy

XI, 288 p. 106 illus., 35 illus. in color.online

Techno-economic modelling of high-value metabolites and secondary products from microalgae cultivated in closed photobioreactors with supplementary lighting

The purpose of this study is to develop an initial computational model to evaluate the techno-economic viability of high-value and secondary resources from microalgae. The isolation of high-value metabolites is the driving product to improve the overall economics. This approach will allow marketing secondary compounds at more competitive rates for applications such as biofuel, biomaterials, food or animal feed supplements. In this assessment, we consider cultivations in flat-panel, airlift and tubular closed photobioreactor [PBR] systems to avoid possible contamination and limit environmental exposures. The facilities are also equipped with supplementary LED lightings and temperature control to improve productivity. Based on the methodology described in this work, we evaluate the techno-economic viability of the suggested systems. A probable productivity range is selected based on the logistic growth with a recovery rate between 60% and 80%. The sensitivity analysis shows that the ratio of high-value metabolites is the most crucial factor determining the economics. Microalgae prices and productivities gain more importance at higher ratios. The sensitivity analyses indicate a low-level impact of productivity and cultivation costs on high priced metabolites.This publication was made possible by the QNRF-MME grant # [MME01-0924-190063] from the Qatar National Research Fund (a member of Qatar Foundation) and the Ministry of Municipality and Environment, Qatar. The findings herein reflect the work, and are solely the responsability of the authors

Producción de Compuestos Orgánicos de Valor Comercial a partir de la Biomasa Microalgal de Scenedesmus Dimorphus

Microalgae are a promising source of commercial organic compounds since its culturing could be integrated to existing industrial processes, promoting joint goals of sustainability and profitability. Yield of serial extractions with n-hexane, ethanol and acetone of Scenedesmus dimorphus was studied. Samples of algal biomass cultured under normal and stressed conditions were taken and lipid content obtained was 162,6 mg/g and 265,8 mg/g, respectively. It was also observed that culture deprived from nutrients not only accumulates lipids (344% w/w increase) but also carbohydrates, astaxanthin and its esters.Results show that it is possible to obtain different organic products from S. dimorphus cultures, with solvents and techniques commonly used in the industrial field but rarely found in microalgae current bibliography.Las microalgas son una prometedora fuente de compuestos orgánicos de valor comercial, ya que su cultivo se puede integrar con el aprovechamiento de corrientes residuales industriales, potenciando tanto la sustentabilidad como la rentabilidad de los procesos productivos.En este trabajo se estudió el rendimiento de extracciones secuenciales, con solventes n- hexano, etanol y acetona, de la biomasa de Scenedesmus dimorphus, cultivada en condiciones control y de estrés nutricional. El contenido lipídico fue de 162,6 mg/g y 265,8 mg/g respectivamente. Se observa que, sometido a falta de nutrientes, el cultivo produce una acumulación no solamente de lípidos (aumento de 344% p/p), sino de carbohidratos, astaxantina y sus ésteres.Los resultados muestran que a partir de cultivos de S. dimorphus es posible obtener distintos metabolitos orgánicos de interés, con métodos y solventes de extendido uso industrial, que no son los que frecuentemente se encuentran en la bibliografía de estudios microalgales

Marine microbial bioprospecting: Exploitation of marine biodiversity towards biotechnological applications—a review

The increase in the human population causes an increase in the demand for nutritional supplies and energy resources. Thus, the novel, natural, and renewable resources became of great interest. Here comes the optimistic role of bioprospecting as a promising tool to isolate novel and interesting molecules and microorganisms from the marine environment as alternatives to the existing resources. Bioprospecting of marine metabolites and microorganisms with high biotechnological potentials has gained wide interest due to the variability and richness of the marine environment. Indeed, the existence of extreme conditions that increases the adaptability of marine organisms, especially planktons, allow the presence of interesting biological species that are able to produce novel compounds with multiple health benefits and high economical value. This review aims to provide a comprehensive overview of marine microbial bioprospecting as a growing field of interest. It emphasizes functional bioprospecting that facilitates the discovery of interesting metabolites. Marine bioprospecting was also discussed from a legal aspect for the first time, focusing on the shortcomings of international law. We also summarized the challenges facing bioprospecting in the marine environment including economic feasibility issues.This report was made possible by the NPRP award (NPRP11S-0110-180248) from the Qatar National Research Fund (a member of The Qatar Foundation). The statements made herein are solely the responsibility of the authors. Special thanks go to the Centre for Sustainable Development for the support

Biomass production of marine microalga Tetraselmis suecica using biogas and wastewater as nutrients

Anaerobic digestion is a suitable method for treating organic wastes and generating biogas. This biogas contains significant amount of CO2 and some other contaminants. The coupling of wastewater treatment with biogas purification using saline microalgae could effectively upgrade biogas (through photosynthetic CO2 fixation) and concurrently remove nutrients from the effluent, while producing valuable algal biomass. In this context, Tetraselmis suecica biomass production with the use of an impurity (CO2) in biogas to supply carbon, and nutrients (nitrogen and phosphorus) from anaerobically-digested piggery effluent (ADPE) was investigated at four operating pH set points (6.5, 7.5, 8.5 and 9.5). Results showed that pH 7.5 produced the optimum conditions for T. suecica growth and biogas-based CO2 removal, with the maximum biomass (59.8 mg L−1 d−1), lipid (25 mg L−1 d−1) and carbohydrate (6.5 mg L-1 d-1) productivities. Under this condition, CO2, total nitrogen and phosphorus removal efficiencies were 94.7%, 96% and 72%, respectively. Furthermore, the results showed no inhibitory effect of dissolved CH4 on the growth of T. suecica at pH 7.5, suggesting the technical feasibility of harnessing marine T. suecica for simultaneous nutrients removal from wastewaters, biogas upgrading, and production of energy-rich algal biomass. This process clearly harnesses anaerobically-digested piggery effluent not only as an asset but also uses an impurity (CO2) in biogas to produce valuable algal biomass

Sustainable cultivation of microalgae by an insulated glazed glass plate photobioreactor

Microalgae growth in closed photobioreactors is greatly inhibited by elevated temperatures caused mainly by the infra-red portion of light. Current passive evaporative cooling systems for temperature control in outdoor photobioreactors are neither economical nor sustainable. Here we built a novel flat plate photobioreactor with its illumination surface customized with insulated glazing units (IGP). The IGP design enabled transmission of more than 50% of visible light while blocking 90% of ultraviolet and infrared radiations. The growth and productivity of Nannochloropsis sp. (MUR 267) in the IGP was compared against conventional flat plate photobioreactors subjected to the full spectrum (HLP) and also externally modified spectrum (CLP) of halogen lights. High temperature (up to 42°C) resulted in no growth in the HLP. Biomass productivities of Nannochloropsis sp. grown in the CLP was significantly higher than the IGP due to higher light transmission and lower temperature profiles recorded in the CLP. Lipid content of Nannochloropsis was highest in the CLP (60.23%) while protein was highest in the IGP (42.43%). All photosynthesis parameters were negatively affected in the HLP. The IGP\u27s ability to remove infrared (heat) makes this newly developed photobioreactor a promising and sustainable cultivation system for mass algal production especially for high value products. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim