Publications by authors named "Andres Mansilla"

Article Synopsis
  • - The study focuses on the Magellan Subantarctic ecoregion, highlighting how accelerated glacial ice melt creates unique environmental conditions that impact marine biodiversity and epiphytic microalgal communities.
  • - Researchers analyzed epiphytic microalgal assemblages on various benthic macroalgae across sites with different glacial and oceanic influences, documenting 67 genera and noting significant variations in diversity based on environmental factors.
  • - Findings revealed that environmental gradients, particularly from glacial influence, are the primary drivers of epiphytic variation, with some potentially harmful microalgae identified, contributing to a better understanding of this complex ecosystem in light of climate change.
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We isolated and characterized the community of cultivable fungi associated with marine macroalgae present in the Magellan sub-Antarctic straits and the South Shetland Islands, Maritime Antarctica, and evaluated their production of bioactive metabolites. A total of 201 filamentous fungal isolates were obtained. The genera Antarctomyces, Pseudogymnoascus, Microdochium, Trichoderma, Cladosporium, Penicillium, Neoascochyta, Entomortierella and Linnemannia were associated with Antarctic macroalgae, with Neoascochyta paspali being the most abundant taxon.

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Sheep farming contributes to the socioeconomic development of small and medium-scale livestock farmers. However, several factors can hinder successful animal production, as is the case for infectious diseases, such as the one caused by Corynebacterium pseudotuberculosis, known as caseous lymphadenitis (CLA). CLA has >90% prevalence in Brazilian herds and antibiotic treatment is not effective, consequently causing significant economic losses to farmers.

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Article Synopsis
  • Methane-cycling is increasingly important in high-latitude ecosystems as global warming releases more organic carbon from permafrost, leading to the study of 387 samples from regions like Siberia, Alaska, and Patagonia.
  • The research integrated physicochemical, climatic, and geographic data with microbial genetic sequences to analyze the structure of methane-related microbial communities, showing that pH significantly influences community composition.
  • Key bioindicator taxa associated with different ecological conditions were identified, such as Methanoregula as generalist methanogens and specific methanotrophs like Methylocystis and Methylobacter, highlighting their role in understanding methane cycling and its impact on greenhouse gas emissions under climate change.
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The paradigm of past climate-driven range shifts structuring the distribution of marine intraspecific biodiversity lacks replication in biological models exposed to comparable limiting conditions in independent regions. This may lead to confounding effects unlinked to climate drivers. We aim to fill in this gap by asking whether the global distribution of intraspecific biodiversity of giant kelp (Macrocystis pyrifera) is explained by past climate changes occurring across the two hemispheres.

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The COVID-19 pandemic has caused an unprecedented health and economic crisis, highlighting the importance of developing new molecular tools to monitor and detect SARS-CoV-2. Hence, this study proposed to employ the carrageenan extracted from algae as a probe for SARS-CoV-2 virus binding capacity and potential use in molecular methods. specimens were collected in the Chilean subantarctic ecoregion, and the carrageenan was extracted -using a modified version of Webber's method-, characterized, and quantified.

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The Cyanidiophyceae, an extremophilic red algal class, is distributed worldwide in extreme environments. Species grow either in acidic hot environments or in dim light conditions (e.g.

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High latitudes are experiencing intense ecosystem changes with climate warming. The underlying methane (CH) cycling dynamics remain unresolved, despite its crucial climatic feedback. Atmospheric CH emissions are heterogeneous, resulting from local geochemical drivers, global climatic factors, and microbial production/consumption balance.

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Freshwater ecosystems are important contributors to the global greenhouse gas budget and a comprehensive assessment of their role in the context of global warming is essential. Despite many reports on freshwater ecosystems, relatively little attention has been given so far to those located in the southern hemisphere and our current knowledge is particularly poor regarding the methane cycle in non-perennially glaciated lakes of the maritime Antarctica. We conducted a high-resolution study of the methane and carbon dioxide cycle in a lake of the Fildes Peninsula, King George Island (Lat.

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The agarophyte (Ahnfeltiales, Rhodophyta) is a globally widespread genus with 11 accepted species names. Two of the most widespread species in this genus, and , may have diverged genetically due to past geographic changes and subsequent geographic isolation. To investigate this genomic and genetic diversity, we generated new plastid (ptDNAs) and mitochondrial genomes (mtDNAs) of these species from four different regions ( - Chile and UK and - Korea and Oregon).

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A partial rbcL sequence of the lectotype specimen of Corallina berteroi shows that it is the earliest available name for C. ferreyrae. Multilocus species delimitation analyses (ABGD, SPN, GMYC, bPTP, and BPP) using independent or concatenated COI, psbA, and rbcL sequences recognized one, two, or three species in this complex, but only with weak support for each species hypothesis.

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Freshwater ecosystems are responsible for an important part of the methane (CH) emissions which are likely to change with global warming. This study aims to evaluate temperature-induced (from 5 to 20 °C) changes on microbial community structure and methanogenic pathways in five sub-Antarctic lake sediments from Magallanes strait to Cape Horn, Chile. We combined in situ CH flux measurements, CH production rates (MPRs), gene abundance quantification and microbial community structure analysis (metabarcoding of the 16S rRNA gene).

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Two species of scallop, Austrochlamys natans ("Ostión del Sur") and Zygochlamys patagonica ("Ostión patagonico") are presently exploited in the southern part of the Magallanes Province (MP). The lack of clarity in taxonomic identification and ecological aspects is generating both erroneous extraction statistics and an unperceived harvesting pressure on A. natans and Z.

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The generitype Bory is an endemic and important kelp from Sub-Antarctic Magellanic ecoregion that shows affinity to extreme salinity, temperature, and photoperiod conditions. Genomic analysis of from Rinconada Bulnes, Punta Arenas, Chile, resulted in the assembly of its organellar genomes. The complete mitogenome is 37,226 base pairs (bp) in length and contains 66 genes (GenBank accession number MN561186), the complete plastid genome is 130,085 bp and has 173 genes (MN561187) and the data assembled 8205 bp of the nuclear ribosomal cistron (MN561188).

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This research focused on the development of carrageenan based biodegradable films incorporated with olive leaves extract (OLE). OLE microbial inhibition and its total phenolics (TP) were evaluated. Carrageenan films were produced by casting technique and were characterized by thickness, water vapor permeability (WVP), color, mechanical properties, and infrared spectroscopy.

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The Katalalixar National Reserve (KNR) lies in an isolated marine protected area of Magellan Sub-Antarctic channels, which represent an important area for marine biodiversity and macroalgal conservation. The present study is the first report of the species , "huiro negro", in the Magellan Sub-Antarctic channels. This finding has implications for macroalgal biogeography and conservation concerns in the Chilean coast.

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(Suhr) Santelices is the most ecologically and economically important kelp from Pacific South America. Here, we contribute to the bioinformatics and evolutionary systematics of the species by performing high throughput sequencing on from Valparaiso, Chile. The complete mitogenome is 37,097 base pairs (bp) in length and contains 66 genes (GenBank accession MK965907), the complete plastid genome is 130,305 bp and has 173 genes (accession MK965908), and the data assembled 7,630 bp of the nuclear ribosomal cistron (accession MK965909).

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Current knowledge about the performance of floating seaweeds as dispersal vectors comes mostly from mid latitudes (30°-40°), but phylogeographic studies suggest that long-distance dispersal (LDD) is more common at high latitudes (50°-60°). To test this hypothesis, long-term field experiments with floating southern bull kelp Durvillaea antarctica were conducted along a latitudinal gradient (30°S, 37°S and 54°S) in austral winter and summer. Floating time exceeded 200d in winter at the high latitudes but in summer it dropped to 90d, being still higher than at low latitudes (<45d).

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Interactions between algae and herbivores can be affected by various factors, such as seasonality and habitat structure. Among herbivores inhabiting marine systems, species of the order Patellogastropoda are considered key organisms in many rocky coasts of the world. species are one of the most dominant macro-herbivores on the rocky shores of the sub-Antarctic ecoregion of Magellan.

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The sub-Antarctic Magellanic ecoregion is a part of the world where ecosystems have been understudied and where the CH cycling and emissions in lakes has not ever been reported. To fill that knowledge gap, a lake and a reservoir located at 53°S were selected and studied during three campaigns equally distributed over one year. Among the parameters measured were CH and CO emissions, as well their dissolved concentrations in the water column, which were determined with high spatial resolution.

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Glacial episodes of the Quaternary, and particularly the Last Glacial Maximum (LGM) drastically altered the distribution of the Southern-Hemisphere biota, principally at higher latitudes. The irregular coastline of Patagonia expanding for more than 84.000 km constitutes a remarkable area to evaluate the effect of Quaternary landscape and seascape shifts over the demography of near-shore marine benthic organisms.

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Homopolymannuronic and homopolyguluronic fractions were obtained by partial hydrolysis of the alkaline extracts from the brown seaweeds Ascoseira mirabilis, Desmarestia menziessi, Desmarestia ligulata and Durvillaea sp. collected in southern Chile. Full characterization of the fractions was achieved by FT-IR and NMR spectroscopy.

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The effects of solar UV radiation on mycosporine-like amino acids (MAAs), growth, photosynthetic pigments (Chl a, phycobiliproteins), soluble proteins (SP), and C and N content of Mazzaella laminarioides tetrasporophytes and gametophytes were investigated. Apical segments of tetrasporophytes and gametophytes were exposed to solar radiation under three treatments (PAR [P], PAR+UVA [PA], and PAR+UVA+UVB [PAB]) during 18 d in spring 2009, Punta Arenas, Chile. Samples were taken after 2, 6, 12, and 18 d of solar radiation exposure.

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Knowledge about the marine malacofauna in the Magellan Region has been gained from many scientific expeditions that were carried out during the 19th century. However, despite the information that exists about molluscs in the Magellan Region, there is a lack of studies about assemblages of molluscs co-occurring with macroalgae, especially commercially exploitable algae such as Gigartina skottsbergii, a species that currently represents the largest portion of carrageenans within the Chilean industry. The objective of this study is to inform about the richness, systematics, and distribution of the species of molluscs associated with natural beds in the Strait of Magellan.

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Article Synopsis
  • Researchers studied how different levels of nitrate affect the growth and production of pigments, mycosporine-like amino acids (MAAs), C:N ratios, and carrageenan yield in a seaweed called Mazzaella laminarioides, which is important for the coastal economy in southern Chile.
  • They grew the seaweed in varying nitrate concentrations (from 0 to 0.75 mm) over 18 days and found that while some pigments and C:N ratios decreased without nitrate, overall growth rates and carrageenan yield remained consistent across all conditions.
  • The study revealed that higher nitrate levels (over 100 times natural levels) did not harm the seaweed's photoprotection or growth, indicating that M. laminario
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