Sebastián Sabatini - Academia.edu (original) (raw)

Papers by Sebastián Sabatini

Marine and Fishery Sciences (MAFIS)

Until 2014 Mar del Plata city discharged its untreated sewage effluents to the intertidal sector.... more Until 2014 Mar del Plata city discharged its untreated sewage effluents to the intertidal sector. This city has a marked seasonality in the urban discharge, varying between 2.8 and 3.5 m3.sec.-1 of effluents before/after summer. The effect on the intertidal benthic community was evaluated in both spatially, in sewage-impacted and reference sites, and temporarily in both the short term, before/after summer, and in long term along nine periods between 1997 - 2014. The bivalve Brachidontes rodriguezii, the ecosystem engineer, reach the maximum dominance and frequency in reference areas. Spatially the presence of opportunistic and tolerant species characterized the impacted areas, while in reference sites sensitive species were prevalent. The opportunistic polychaete species Capitella "capitata" sp. and Alitta succinea were dominant near the sewage discharge in firsts periods. In other periods the indicator species were Rhynchospio glutaea or Boccardia spp. From 2008 the invad...

Marine and Freshwater Research

Context Bivalve fishery represents an important socio-economic resource in Río Negro province, an... more Context Bivalve fishery represents an important socio-economic resource in Río Negro province, and Mytilus platensis is the main exploited species. Thus, biomonitoring trace metals in this mussel is particularly relevant for both environmental protection and human consumption. Aim Anthropogenic pollution and its environmental impact on mussels were experimentally evaluated in situ in two coastline sites of northern Patagonia. Methods Trace metal concentrations were quantified in the water of a harbour area (Port of San Antonio Este) and a reference site (Isla Mejillón), an extraction location of M. platensis, were quantified. Metal accumulation and its effects on metabolic parameters were also measured in mussels. Results Higher concentrations of chromium, nickel and zinc in water were registered in the harbour, along with copper and chromium in gills, digestive gland and mantle of M. platensis, were registered in the harbour. Furthermore, superoxide dismutase activity was augmented...

Limnologica, Dec 1, 2011

The effect of chronic exposure to Escherichia coli on morphometrical parameters, different antiox... more The effect of chronic exposure to Escherichia coli on morphometrical parameters, different antioxidant defenses, lipid peroxidation and protein oxidation has been studied in digestive gland of the freshwater mussel Diplodon chilensis in the laboratory during 6 weeks. In, a parallel field study, we evaluated morphometrical and oxidative stress parameters in digestive glands of mussels collected from a sewage polluted area (SMA) and from a pristine area (control). Both sites were characterized by analyzing bacteriological and physic-chemical parameters. In the laboratory D. chilensis was able to filter bacteria at high concentrations with a clearing rate of 0.510 ± 0.036 L/h per gram of dry soft tissue mass. The digestive gland mass to shell length ratio (DGM/SL), reduced glutathione (GSH), lipid peroxidation, as concentration of thiobartituric acid reactive substances (TBARS), and glutathione-S-transferase (GST) activity of mussels fed with bacteria were significantly higher than those of control mussels after the fourth week. Fecal bacteria in lake water samples were undetectable in the control, and higher than 24,000 MPN (most probable number)/100 mL in SMA. DGM/SL was higher in SMA. No differences between sites were observed in total lipid and protein content, neither in superoxide dismutase activity. GSH content was higher in SMA, with no difference in the oxidized form. GST activity and MDA were significantly higher in SMA but protein oxidation was not affected.

Ecotoxicology and Environmental Safety, May 1, 2009

The aim of this work was to assess the effects of 1 week copper exposure (6.2, 108, 210 and 414mi... more The aim of this work was to assess the effects of 1 week copper exposure (6.2, 108, 210 and 414microM) on Scenedesmus vacuolatus and Chlorella kessleri. The strains showed different susceptibility to copper. Copper content was determined in both strains by total X-ray reflection fluorescence analysis (TXRF). In S. vacuolatus, the increase of medium copper concentration induced an augmentation of protein and MDA content, and a significant decrease in the chlorophyll a/chlorophyll b ratio. S. vacuolatus showed a significant increase of catalase activity in 210 and 414microM of copper, and a significant increment of SOD activity and GSH content only in 414microM of copper. On the contrary, C. kessleri did not show significant differences in these parameters between 6.2 and 108microM of copper. Increased copper in the environment evokes oxidative stress and an increase in the antioxidant defenses of S. vacuolatus.

Phycologia, 2011

The aim of this work was to determine the responses to sublethal copper exposure (20 and 40 mM Cu... more The aim of this work was to determine the responses to sublethal copper exposure (20 and 40 mM CuCl 2) in two Chlamydomonas reinhardtii strains: the wild type 4A + and the pleiotropic mutant cur9, originally selected as a coppertolerant phenotype in mixotrophic conditions. Bioassays were performed in both autotrophic and mixotrophic media, under low irradiation (50 mmol m 22 s 21). At the onset, Cu 2+ concentration in culture media was estimated by MINEQL software. Oxidative stress indicators, such as changes in photosynthetic pigment ratios, catalase activity, concentration of thiobarbituric acid reactive substances (TBARS) and growth rate, demonstrated a better performance of the wild type and the mutant strain in autotrophic and mixotrophic conditions, respectively. Moderate oxidative stress was accompanied by ultrastructural changes, such as accumulation of starch and vacuoles with electronic-dense deposits and membranous structures together with mild thylakoidal and mitochondrial crest disorganization. In mixotrophic conditions isocitrate lyase (ICL) activity peaked after 72 h incubation. An inverse relation between catalase (CAT) and ICL activities was verified and proved to be a good indicator of oxidative stress correlating consistently with other characteristic features such as depression in growth rate or increase in TBARS dosage.

Journal of the Marine Biological Association of the United Kingdom, Dec 22, 2015

The gastropod Buccinanops globulosus is commonly used as bioindicator of tributyltin (TBT) contam... more The gastropod Buccinanops globulosus is commonly used as bioindicator of tributyltin (TBT) contamination due to its high imposex incidence in maritime traffic areas. The aim of this study was to evaluate both oxidative stress in B. globulosus at three sites with different maritime activity, and imposex incidence in Nuevo gulf, Argentina. Oxidative stress parameters in digestive glands, like superoxide dismutase (SOD) and glutathione-Stransferase (GST) activities, reduced glutathione levels (GSH), and oxidative damage to lipids, estimated as thiobarbituric acid reactive substances (TBARs) as well as imposex parameters (% imposex and female penis length-FPL-) were measured in females. Gastropods from the harbour area showed 100% imposex, the highest FPL and TBARs content, as well as GSH levels and SOD activity.

Canadian Journal of Zoology, Feb 1, 2021

Climate change is producing sea level rise and deoxygenation of the ocean, altering estuaries and... more Climate change is producing sea level rise and deoxygenation of the ocean, altering estuaries and coastal areas. Changes in oxygen availability are expected to have consequences on the physiological fitness of intertidal species. In this work we analyze the coping response of the intertidal stout razor clam (Tagelus plebeius (Lightfoot, 1786)) to extreme environmental changes in oxygen concentration. Their biochemical responses to normoxia, hypoxia, and hyperoxia transition at different intertidal level (low–high) were measured through an in situ transplant experiment. The high intertidal level negatively affected the analyzed traits of the T. plebeius populations. The differences in reactive oxygen species production, total oxyradical scavenger capacities, and catalase activity also suggested more stressful conditions at the high level where long-term hypoxia periods occur. Both hypoxia and re-oxygenation provoked re-adjustments in the antioxidant responses and higher lipid oxidative damage (normoxia &amp;lt; hypoxia &amp;lt; re-oxygenation). The observed responses in transplanted clams at the opposite intertidal level suggested the potential acclimation of T. plebeius to cope with new environmental conditions. These findings are discussed within a global changing context where both increasing deoxygenation conditions and sea level rise are predicted to be exacerbated in the area driven by climate change.

Frontiers in Physiology, Mar 27, 2018

Limnologica, 2014

Three populations of Diplodon chilensis (Hiridae, Bivalvia) from North Patagonia (Lacar lake, Arg... more Three populations of Diplodon chilensis (Hiridae, Bivalvia) from North Patagonia (Lacar lake, Argentina) have been studied to determine how organic matter (OM) influence their growth, density, morphometric and metabolic parameters in two pristine sites (Yuco and Nonthué) and in a growing touristic locality (San Martín de los Andes Bay, site SMA) affected by urban discharges. In Nonthué (chemical and biological oxygen demand ratio COD/BOD ratio of 4.7), a dense neighboring forest provides higher quantities of vegetal detritus compared to Yuco, while in SMA the OM input increase is related to anthropogenic impact, mainly sewage discharges, which is more biodegradable (COD/BOD ratio of 1.7). Our results show that population's size distribution and growth rates are affected positively by increased OM, independently of its natural or anthropogenic origin. The modal shell length interval for SMA and Nonthué is twofold higher (70 mm), in agreement to the growth rate increase (k = 0.079), compared to Yuco (35 mm, k = 0.045). The morphometric relationships between size-size and size-mass show a higher slope for SMA and Nonthué, which underline allometric differences between these two populations and the Yuco's one. The lower population densities in both sites (SMA 33 ind./m 2 and Nonthué 76 ind./m 2) compare to Yuco (176 ind./m 2) and the absence of individuals younger than 7 and 5 years old, respectively, in SMA and Nonthué could be related to the higher allochthonous OM content in the sediments and total suspended solids in water. Increased OM due to urban pollution in SMA bivalves leads to higher oxidative damage to lipids, which is not counterbalanced by the higher detoxification enzyme glutathione-S-transferase activity. Hence, we can conclude that pollution would explain the drastic reduction in population density, probably related to a high impair in the juvenile's survival/recruitment, the higher observed mortality and the lower population longevity. When increased OM is supply by the forest, like in Nonthué, this has less negative effect on population density and no effect on longevity at all. However, a negative effect of oxygen depletion due to increased OM (either anthropogenic or natural) on juvenile survival cannot be discarded, but further studies should be carried out to support this idea.

Frontiers in Physiology, Feb 23, 2018

Phycologia, Mar 1, 2012

The effect of copper-imposed oxidative stress on isocitrate lyase (ICL) activity was studied in a... more The effect of copper-imposed oxidative stress on isocitrate lyase (ICL) activity was studied in a Chlamydomonas reinhardtii wild type and a copper-tolerant pleiotropic mutant strain. Suspension batch bioassays were performed adding copper chloride under moderate irradiation. Two harvest points were selected to represent the acute and restoration phases and oxidative stress indicators were measured: antioxidative metabolites, phenolic compounds, ascorbic acid, abundance of thiobarbituric reactive substances, and activities of detoxifying enzymes such as catalase and ascorbate peroxidase. Copper stress under moderate irradiance favours acetate assimilation through enhanced ICL activity, especially in the acute phase. Though the mutant strain exhibited at least twofold ICL activity in the acute phase compared to the wild type, there was no significant difference in copper tolerance between strains. The higher ICL activity under copper stress may be an adaptation to promote mixotrophic organic carbon assimilation when photosynthetic carbon dioxide fixation is impaired. Thus, the higher ICL activity has the potential to be a useful indicator in acetate-flagellate bioassays.

Durante gran parte de la historia deldesarrollo humano los ambientes acuáticos han sido considera... more Durante gran parte de la historia deldesarrollo humano los ambientes acuáticos han sido considerados como meras fuentes de abastecimiento de aguay eliminación de residuos. La creenciade que todo lo que se vertía en el medio acuático se diluiría debido a la inmensidad de los océanos (algo más delas dos terceras parte de la superficie denuestro planeta), hizo que la idea de lacontaminación acuática resultara algoimpensado. Hoy en día se sabe que tanto las actividades humanas como cierLos indicadores de lacontaminación de lastos procesos naturales pueden afectarla calidad de las aguas superficiales ysubterráneas. Es un tema complejo deenorme importancia ambiental, económica y científica, que ha sido objeto dedebate en los últimos años.Fil: Sabatini, Sebastian Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; ArgentinaFil: Ruíz, María D.. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; ArgentinaFil: Calcagno, Javier Ángel. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Ecotoxicology and Environmental Safety, Jul 1, 2018

This study investigated metal accumulation and oxidative effects in mantle, gill and digestive gl... more This study investigated metal accumulation and oxidative effects in mantle, gill and digestive gland of the ribbed mussel Aulacomya atra from the Argentinean North Patagonian coastline. Mussels were transplanted over an 18month period from a site with low anthropogenic impact to a harbor site with higher seawater concentration of aluminum, chromium, copper, manganese, nickel and zinc. Total trace metal concentration in seawater did not change throughout the 18-month transplant in either site. A. atra bioaccumulated metals in digestive gland, gills and mantle at different levels. Digestive gland had the highest concentration of metals, especially towards the end of the transplant experiment in the harbor area. Mussels transplanted to the harbor site experienced an upregulation in their antioxidant system, which likely explains the lack of oxidative damage to lipids despite higher metal accumulation. These results demonstrate that A. atra selectively accumulates metals from the water column and their prooxidant effects depend on the tissue antioxidant defenses and the exposure time.

reponame:CONICET Digital (CONICET), Apr 29, 2019

This study investigated the effects of pollution and its interaction with temperature on the oxid... more This study investigated the effects of pollution and its interaction with temperature on the oxidative status of the ribbed mussel Aulacomya atra in the southern Atlantic Patagonian coast. Animals were collected from four sites with different degree and type of human activity impact, during the summer and winter of 2011. Seawater chromium, copper, manganese, nickel and zinc concentrations were measured, as well as metal accumulation, lipid peroxidation, protein oxidation, reduced glutathione levels, and enzymatic activities of superoxide dismutase and glutathione-S-transferase in gills and digestive glands. Metal bioaccumulation and oxidative stress responses in both tissues were generally higher in mussels from harbor areas. Water temperature had a remarkable effect on gill SOD activity and protein oxidation during winter in mussels from all locations. Methodologically, we conclude that measuring both metal bioaccumulation and oxidative stress responses allowed for a more accurate assessment of the biological effects of metal present in seawater.

Ecotoxicology and Environmental Safety, 2020

An in-situ experiment was performed to study metabolic responses of the freshwater mussel Diplodo... more An in-situ experiment was performed to study metabolic responses of the freshwater mussel Diplodon chilensis to water contaminated by leachates from an open dump and cattle activity, in order to analyze both the effects of those contaminants on aquatic environments and the potential use of a native bivalve to evaluate the effects of anthropic influence and eutrophication. Bivalves from a reference site were cage-transplanted to a control site (site A) and to a temporal water pond (site B) over 30 and 60 periods. Water quality analyses revealed that the site B was affected by anthropogenic influence. Mussel's hemocytes from site B showed 50% lower reactive oxygen species production and 130% higher lysosomal membrane stability in the site B mussels. In addition, no oxidative stress was evident in gills, despite the elevated copper and iron concentrations recorded in the site B water samples (Cu B = 0.3350 ± 0.0636 mg. L −1 vs. Cu A = 0.0045 ± 0.0007 mg. L −1 ; Fe B = 3.8650 ± 0.4031 mg. L −1 vs. Fe A = 0.0365 ± 0.0049 mg. L −1). In contrast, the adductor muscle accumulated more Fe (~10-20-fold) than the gills and showed signs of oxidative stress, e.g. superoxide dismutase activity and TBARS levels were increased by 10% were 34%, respectively, in the site B compared with the site A after 60 days of exposure. Additionally, the adductor muscle showed signs of anaerobic metabolism activation. Cu is accumulated in gills from both sites' individuals, at 60 days, in concordance with the increase in the activity of the cu-containing enzyme cytochrome-c-oxidase. There was a reduction in the overall condition and digestive gland index in bivalves exposed at site B, associated with diminished levels of lipid and protein contents. Metal-pollution and eutrophication affects D. chilensis metabolism and is associated to tissue-specific exposure, anaerobic metabolism and general energetic condition depletion.

Frontiers in Physiology, 2018

Ecotoxicology and environmental safety, Jan 21, 2018

The aim of this study was to analyze the biochemical alterations in the golden mussel Limnoperna ... more The aim of this study was to analyze the biochemical alterations in the golden mussel Limnoperna fortunei under dietary glyphosate exposure. Mussels were fed during 4 weeks with the green algae Scenedesmus vacuolatus previously exposed to a commercial formulation of glyphosate (6 mg L active principle) with the addition of alkyl aryl polyglycol ether surfactant. After 1, 7, 14, 21 and 28 days of dietary exposure, glutathione-S-transferase (GST), catalase (CAT), superoxide dismutase (SOD), acetylcholinesterase (AChE), carboxylesterases (CES) and alkaline phosphatase (ALP) activities, glutathione (GSH) content and damage to lipids and proteins levels were analyzed. A significant increase (72%) in the GST activity and a significant decrease (26%) in the CES activity in the mussels fed on glyphosate exposed algae for 28 days were observed. The ALP activity was significantly increased at 21 and 28 days of dietary exposure (48% and 72%, respectively). GSH content and CAT, SOD and AchE act...