About
68
Publications
31,817
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,885
Citations
Introduction
Current research work of my group is focused on microalgal biorefineries with special emphasis in marine diatoms. In particular, different aspects related to the production of lipids, pigments and extracellular polymeric substances (EPS) are investigated, as well as the possible applications of the diatom cell walls or frustules in nanotechnology and material industry.
Current institution
Publications
Publications (68)
Se presenta, de forma breve, estilo manual, la selección de microalgas de acuerdo con el objetivo del proyecto; los factores más importantes de los cultivos; la separación y cosecha de microalgas; los procesos de extracción de metabolitos; y la integración con la biorremediación en procesos de biorrefinería.
Buenos Aires, 28 de Junio de 2023. Organizado en el marco de la red RENUWAL 320RT0005-Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CYTED) por:
Biodiesel production from the microalgal oil of the estuarine diatom Halamphora coffeaeformis has proven to be technically viable. However, a fuller understanding of the environmental factors that regulate its tolerance and neutral lipid accumulation is required for improved mass cultivation in seawater-based outdoor raceway ponds. Meteorological c...
Diatoms are a diverse group of unicellular microalgae with broad biotechnological and industrial applications. Recent studies have revealed that some species from the genus Halamphora accumulate high quantities of lipids, which make them potentially suitable for biodiesel production. However, due to their high phenotypic plasticity, molecular phylo...
Diatoms are unicellular organisms containing red algal‐derived plastids that probably originated as result of serial endosymbioses between an ancestral heterotrophic organism and a red alga or cryptophyte algae from which has only the chloroplast left. Diatom mitochondria are thus believed to derive from the exosymbiont. Unlike animals and fungi, d...
In the search for energy sources to replace fossil fuels, microalgae have shown promising characteristics. Their cultures have several advantages over the conventional crops used for commercial biodiesel: they have fast growth rates and a high lipid content and can grow in environments unfit for agriculture. However, relatively few species have so...
Omega-3 eicosapentaenoic fatty acid (C20:5; EPA), β-glucan and fucoxanthin have received widespread attention owing to their potential industrial applications; however, their availability is currently limited to unsustainable sources such as fish oils and macroalgae. Though some species of diatoms are also a natural source of these metabolites, pro...
The large-scale culture of microalgae has become a focus of interest for the biorefinery industry, combining the production of biofuels with that of other value-added bioproducts and thus increasing the profitability of the process. In order to evaluate its potential as biodiesel feedstock under a biorefinery approach, the biomass, pigment, nutrien...
The vast majority of the world’s fishery by-products are utilized in the fish farming industry. However, due to the high cost and unsustainability of these by-products, alternative sources must be found. Marine diatoms produce important amounts of fatty acids, sterols, proteins and carbohydrates. In this work, we assessed the nutritional value of H...
Marine microalgae synthetize great amounts of essential metabolites such as fatty acids and amino acids. In addition, their exposure to stress factors can induce the overproduction of these desirable metabolites. Thus, in this work, we assessed the effect of low-temperature stress on lipid production and composition of the diatom Cylindrotheca clos...
Three-Dimensional Reconstruction of Halamphora coffeaeformis Frustule from Scanning Electron Micrographs - Volume 26 Supplement - Francisco Ezequiel Navarro, Cecilia Angelines Popovich, Miguel Sánchez, Ignacio Costilla, Cecilia Gutierrez Ayesta, Patricia Leonardi
The marine benthic diatom Halamphora coffeaeformis is a potential feedstock for biodiesel production. This species shows high growth rates, important triacylglycerol (TAG) contents and grows in seawater making large-scale cultivation advantageous. Moreover, sustainable biofuel production in future biorefineries requires the implementation of techno...
The use of microalgae as triacylglycerides (TAG) feedstock for biodiesel is a widely researched field in the development of new technologies. In order to underpin the potential of microalgal biodiesel as a possible substitute in the biofuel industry, more detailed data is therefore required on these aspects. This study assesses the growth, TAG accu...
The influence of light stress and trophic environmental conditions on the production of astaxanthin, other xanthophylls and lipids from an Argentinian strain of Haematococcus pluvialis was investigated. Microalgae cultures were incubated for two weeks in autotrophic or mixotrophic conditions (with sodium acetate in the culture medium) and subjected...
The growth, lipid accumulation and bioproducts of the marine diatom Halamphora coffeaeformis were evaluated in a hybrid two-stage culture using seawater enriched with nutrients and without vitamins. The influence of dissolved and internal nutrients on growth and lipid accumulation was also analyzed. Total lipid content increased in the declining ph...
Oleaginous microalgae have been proposed as a sustainable alternative biomass to produce biodiesel in order to substitute conventional vegetable oils derived from oilseed crops. Particularly, recent studies pointed out the potential of N. oleoabundans, cultured in seawater or in anaerobically digested dairy manure, to produce triglycerides with hig...
Understanding phytoplankton species-specific responses to multiple biotic and abiotic stressors is fundamental to assess phenological and structural shifts at the community level. Here, we present the case of Thalassiosira curviseriata, a winter-blooming diatom in the Bahía Blanca Estuary, Argentina, which displayed a noticeable decrease in the pas...
The lipid content, composition and productivity of the marine benthic diatom Halamphora coffeaeformis were studied in order to evaluate its potential as feedstock for biodiesel production. Cultures were carried out in two stages: I) in photobioreactors (PBRs) to increase the biomass as inoculum for larger volumes, and II) in raceway ponds to increa...
The development of the phytoplankton winter bloom and the accumulation of particulate suspended matter (PSM) inside sediment collectors were assessed in the inner zone of the Bahía Blanca Estuary. The phytoplankton bloom (chlorophyll up to 25 μg l−1 and abundance up to 8 × 106 cells l−1) was related with high levels of dissolved inorganic nutrients...
Abstract.- Screening of local microalgae species with potential for oil production is essential to achieve successful
commercial large-scale cultures. In this study, identification of a South American species of Nannochloropsis was carried
out using molecular and phylogenetic analyses of chloroplastic and nuclear genes, rcbL and 18S rDNA, respectiv...
Haematococcus pluvialis is an oleaginous microalga which has been previously described as an important source of astaxanthin and, recently, of triacylglycerol (TAG) for biodiesel production. In this work, our purpose was to describe the effects of light-induced stress on H. pluvialis lipid metabolism. For this end, native strain from Bahía Blanca (...
contínuo de observación y control de medidas y evaluaciones para un propósito definido. El monitoreo es una herramienta importante en el proceso de evaluación de impactos, y en cualquier programa de seguimiento y control (Sors, 1987). Actualmente existe un fuerte consenso sobre que el monitoreo ambiental no e...
A detailed lipid characterization of Scenedesmus
acutus PVUW12, with emphasis on the evaluation of triacylglycerols
(TAGs) as a biodiesel feedstock, is presented. When
algal cells were grown in nitrogen-free medium (N stress), a
lipid increase was detected that was mainly due to TAG
accumulation. In situ fluorescence measurements allowed
the kineti...
The development of effi cient, rapid and species-specifi c techniques is indispensable for assessing growth and neutral lipid yield in microalga cultures for biodiesel oil production. Nannochloropsis oculata is a small microalgae with a thick cell wall. In vivo techniques to es-timate cell density, chlorophyll a and neutral lipids are reported. A c...
Abstract. The freshwater microalga Neochloris oleoabundans has been recognized as a promising oil feedstock, due to its capacity to accumulate lipids. Particularly, recent studies pointed out the potential of N. oleoabundans, cultured in sea water or in anaerobically digested dairy manure, to produce triglycerides with high content of monounsaturat...
We examined austral summer phytoplankton data (December-March) that cover the years 1978-2008 and compared with physico-chemical and meteorological variations in the Bahía Blanca Estuary, Argentina. During the years 1978-1982, 1992-1993 and 2006-2008, counts of phytoplankton abundance showed an increase in recent summers; from a mean value of 12×10...
The Bahía Blanca Estuary is considered to be highly eutrophic due to its very high nutrient concentrations. Long-term studies in this estuary have shown that the winter-early spring bloom can be considered as the development of a diatom assemblage (Thalassiosira spp. and Chaetoceros spp.) with T. curviseriata as the dominant species. From 2003 and...
The diatom Thalassiosira minima was first recorded in the Bahía Blanca Estuary in 1992. In 1992–1993 it exhibited a broad seasonal occurrence. A recent survey
(2006–2007) showed a seasonal appearance restricted mainly to summer together with a greater relative abundance within the
phytoplankton. A close connection was found with warmer, more saline...
Under the contemporary scenario of global climate change and increasing coastal eutrophication, baseline studies of phytoplankton diversity and distribution in relation to habitat conditions constitute the first approach to evaluate potential shifts at the base of the food webs. Here we present data of phytoplankton species composition and environm...
The freshwater microalga Neochloris oleoabundans was used to study algal lipid production in enriched natural seawater, in order to assess its suitability as biodiesel feedstock. Optimal and nitrogen-stress (N-stress) conditions were analyzed. Under optimal conditions, the strain's growth rate was 0.73 div day(-1) and the biomass concentration was...
Since the fatty acid ester profile of a given biofuel is relatively consistent with the source’s fatty acid profile, the properties
of the biodiesel produced from a particular feedstock exhibit predictable quality. Thus, lipid fractions and the fatty acid
composition of stationary growth-phase cultures of the local strains of the diatoms Skeletonem...
The phytoplankton of the Bahía Blanca Estuary, Argentina, has been surveyed since 1978. Chlorophyll a, phytoplankton abundance, species composition and physico-chemical variables have been fortnightly recorded. From 1978 to
2002, a single winter–early spring diatom bloom has dominated the main pattern of phytoplankton interannual variability. Such...
The vulnerability of the pejerrey Odontesthes bonariensis population in Lake Chasicó was assessed under different climate change conditions. During the sampling period, the water temperature was adequate for fish reproduction and to sustain an adequate sex ratio. Climate-driven higher temperatures, however, may severely distort population structure...
The lipid content and composition of Haematococcuspluvialis exposed to stress conditions were analyzed to assess the potential of this microalga as a biodiesel feedstock. The total lipid content of control cells was 15.61% dw, whereas that of cells exposed to continuous high light intensity with nitrogen-sufficient medium (A-stress condition) or un...
Land-derived materials are regulated by coastal and shelf environmental conditions before being transported to the open sea. It is of great concern to understand the processes and to establish the extent in which they modify terrestrial compound fluxes, such as nutrients, that end up in the oceans. At present, one of the topics that arouses the hig...
The inner zone of the Bahía Blanca Estuary is shallow, nutrient-rich and turbid. Tidal energy and water turbulence strongly affect the water column resulting in a well-mixed structure and high concentrations of suspended sediment. The phytoplankton community is mostly dominated by diatoms and the annual pattern has been characterized by a recurrent...
The seasonal pattern of the phytoplankton-aloricate ciliate community is an adequate indicator of trophic coupling and nutrient cycling in coastal environments. The size-fractionated, abundance, biomass and composition of a phytoplankton-aloricate ciliate community were ascertained in the Bahía Blanca Estuary from February 1994 to February 1995. In...
A spatial and temporal study on data collected along the longitudinal gradient of the Principal Channel of Bahía Blanca estuary, Argentina, was carried out during 1992–1993. At nine stations, phytoplankton abundance, chlorophyll a (Chl-a) concentration, inorganic nutrient levels, Secchi disk depth, euphotic depth:mixing depth ratio (Zeu:Zm), salini...
The inner zone of Bahia Blanca Estuary is a shallow, well-mixed, highly turbid, and nutrient-rich temperate ecosystem. The phytoplankton annual cycle is characterized by a recurrent winter/early-spring diatom bloom. From May to August 2002 a research program aimed to describe the potential relations between the dynamics of phytoplankton and nutrien...
Resumen: La zona interna del estuario de Bahía Blanca es un ambiente somero caracterizado por poseer altos niveles de nutrientes durante el otoño y una floración de diatomeas en invierno a diferencia del funcionamiento general del resto de los ambientes marino costeros templados como éste. El objetivo de este trabajo es detectar posibles cambios en...
Long-term phytoplankton studies in the Bahia Blanca estuary showed a seasonal pattern characterized by a winter-early spring bloom of diatoms dominated by Thalassiosira curviseriata. Laboratory experiments were carried out to elucidate the influence of irradiance, temperature and salinity on the growth rate of T.curviseriata. The maximum daily grow...
