Time since fire as a driver of taxonomic and phylogenetic patterns of grassland plant communities.

Fire plays a key role in grasslands, determining the distribution and evolution of species and boundaries with neighboring ecosystems. Evidence of community-wide responses to fire is largely based on taxonomic and functional descriptors, while the phylogenetic dimension is overlooked. Here we evaluated how the taxonomic and phylogenetic structure of grassland plant communities responded to a time since fire (TSF) gradient. We sampled 12 communities in Southern Brazil under varying TSF and calculated taxonomic species richness (S) and dominance (D), phylogenetic diversity (PD), and mean phylogenetic distances (MPD). We used Structural Equation Models to test the relationships between the environmental gradient and community descriptors. Communities with longer TSF presented higher PD and MPD but lower species richness and increased taxonomic dominance. These sites were dominated by monocots, specifically C4 grasses, but also presented exclusive clades, whereas recently-burned sites presented lower taxonomic dominance and more species distributed in a wider variety of clades. Our results indicate that these scenarios are interchangeable and dependent on fire management. Fire adaptation was not constrained by phylogenetic relatedness, contrasting with previous findings for tropical savannahs and indicating that temperate and tropical non-forest ecosystems from South America respond differently to fire, possibly due to different evolutionary histories.

Diversity of vegetable landraces in the Pampa biome of Brazil and Uruguay: utilization and conservation strategies.

The historical meeting between originally American people, European colonizers, and slaved peoples from Africa in the biome Pampa in South Brazil and Uruguay involved a cultural syncretism and a great genetic diversity of landraces of cultivated species. Genetic richness evolved by selection and cultural processes in response to different environments, cultural backgrounds, and needs. This review summarized the knowledge on vegetable and maize landraces in South Brazilian and Uruguayan Pampa biome, to design a strategy towards the rediscovery, conservation, and sustainable use. Landraces diversity maintained in situ and ex situ is described, specific case studies are presented, and the main problems and tools towards landraces re-valorization are discussed. We show that traditional family farming systems maintain diverse vegetable species, mainly squashes (Cucurbita spp.), sweet potato (Ipomoea batatas), beans (Phaseolus spp.), onion (Allium cepa), peppers (Capsicum spp.), tomato (Solanum lycopersicum), next to leafy vegetables and maize, among others. We propose the priority of systematic surveys as a basis for monitoring genetic erosion, increasing complementariness between in situ and ex situ conservation, and implementing sustainable conservation and utilization. The case studies highlight genetic diversity within each cultivated species, with different crop physiological responses; disease resistances, different quality traits and associated uses, from animal feeding in maize to a range of culinary uses linked to traditional culture in maize and vegetable species, and ornamental uses of specific Capsicum and Cucurbita. Some landraces were the basis for breeding, where improved cultivars allowed the competitiveness of landrace germplasm in the markets. Renewed industrialized products allowed the competitive and sustainable use of Capsicum landraces in Brazilian farmers communities. Strategies towards in situ conservation improvements and valorization are discussed; emphasizing the role played by agroecology, community seed banks and custodian farmers, participatory plant breeding, promotion of landraces specialties among consumers, and the need of research and capacity building, among others. Farmers' participation in the decisions is a key factor, along with the academia and the public sector. Landraces and associated knowledge are treasures to be used to benefit from farmers to consumers, directing the course of agriculture towards sustainable directions.

Using multilayer perceptron and similarity-weighted machine learning algorithms to reconstruct the past: A case study of the agricultural expansion on grasslands in the Uruguayan savannas.

Changes in land use and land cover (LULC) have significant implications for biodiversity, ecosystem functioning, and deforestation. Modeling LULC changes is crucial to understanding anthropogenic impacts on environmental conservation and ecosystem services. Although previous studies have focused on predicting future changes, there is a growing need to determine past scenarios using new assessment tools. This study proposes a methodology for LULC past scenario generation based on transition analysis. Aiming to hindcast LULC scenario in 1970 based on the transition analysis of the past 35 years (from 1985 to 2020), two machine learning algorithms, multilayer perceptron (MLP) and similarity weighted (SimWeight), were employed to determine the driver variables most related to conversions in LULC and to simulate the past. The study focused on the Aristida spp. grasslands in the Uruguayan savannas, where native grasslands have been extensively converted to agricultural areas. Land use and land cover data from the MapBiomas project were integrated with spatial variables such as altimetry, slope, pedology, and linear distances from rivers, roads, urban areas, agriculture, forest, forestry, and native grasslands. The accuracy of the predicted maps was assessed through stratified random sampling of reference images from the Multispectral Scanner (MSS) sensor. The results demonstrate a reduction of approximately 659 934 ha of native grasslands in the study area between 1985 and 2020, directly proportional to the increase in cultivable areas. The MLP algorithm exhibited moderate performance, with notable errors in classifying agriculture and grassland areas. In contrast, the SimWeight algorithm displayed better accuracy, particularly in distinguishing grassland and agriculture classes. The modeled map using SimWeight accurately represented the transitions between grassland and agriculture with a high level of agreement. By modeling the 1970s scenario using the SimWeight model, it was estimated that the Aristida spp. grasslands experienced a substantial reduction in grassland coverage, ranging from 9982.31 to 10 022.32 km2 between 1970 and 2020. This represents a range of 60.8%-61.07% of the total grassland area in 1970. These findings provide valuable insights into the driving factors behind land use change in the Aristida spp. grasslands and offer useful information for land management, conservation, and sustainable development in the region. The study's main contribution lies in the hindcasting of past LULC scenarios, utilizing a tool used primarily for forecasting future scenarios. Integr Environ Assess Manag 2023;00:1-16. © 2023 SETAC.

The ephemeral record: The role of opportunistic animal resources in the archaeology of Pampa and Patagonia.

The acquisition of opportunistic animal resources by hunter-gatherers-such as scavenged carcasses-is a well-known subsistence strategy. It is frequently mentioned in the context of the history of early human evolution, but not regularly considered among the strategies utilized by more recent foragers of the Southern Cone of South America. Historical and ethnographic information presented here suggests that the use of opportunistic animal resources was a strategy used under a number of conditions but only partially documented in the archaeological literature. We also present archaeological evidence from four sites-Guardia del Río, Paso Otero 1, Ponsonby, and Myren-in different Pampean and Patagonian settings where relevant guanaco (Lama guanicoe) bone assemblages were recovered. These sites record minimal anthropic involvement, basically cut marks on some guanaco bones accompanied by few stone tools, that we interpret as evidence for access and use of water logged immobilized or recently dead animals. Archaeological evidence for the use of these scavenging strategies is difficult to obtain at large archaeological sites that usually result from multiple occupations, since the distinction between the acquisition of actively pursued versus opportunistic animal resources is not straightforward. One conclusion from our review is that the best places to find and recognize this evidence are archaeological sites resulting from ephemeral occupations. The inclusion of these sites gives us access to crucial and rarely documented evidence for the long-term survival of hunter-gatherers.

Pharmacokinetic Profile Evaluation of Novel Combretastatin Derivative, LASSBio-1920, as a Promising Colorectal Anticancer Agent.

LASSBio-1920 was synthesized due to the poor solubility of its natural precursor, combretastatin A4 (CA4). The cytotoxic potential of the compound against human colorectal cancer cells (HCT-116) and non-small cell lung cancer cells (PC-9) was evaluated, yielding IC50 values of 0.06 and 0.07 µM, respectively. Its mechanism of action was analyzed by microscopy and flow cytometry, where LASSBio-1920 was found to induce apoptosis. Molecular docking simulations and the enzymatic inhibition study with wild-type (wt) EGFR indicated enzyme-substrate interactions similar to other tyrosine kinase inhibitors. We suggest that LASSBio-1920 is metabolized by O-demethylation and NADPH generation. LASSBio-1920 demonstrated excellent absorption in the gastrointestinal tract and high central nervous system (CNS) permeability. The pharmacokinetic parameters obtained by predictions indicated that the compound presents zero-order kinetics and, in a human module simulation, accumulates in the liver, heart, gut, and spleen. The pharmacokinetic parameters obtained will serve as the basis to initiate in vivo studies regarding LASSBio-1920's antitumor potential.

Emergence of Mansonella sp. in free-ranging primates in southern Brazil.

Mansonellosis is a neglected and emerging tropical disease. Among all zoonotic filarial diseases, it is probably the most prevalent and least studied, with approximately 114 million people infected. The parasites of Mansonella spp. are among the most common blood parasitemias and are widely found in Africa and Latin America. Through molecular analysis of blood samples from free-ranging primates Sapajus nigritus (n 33) and Alouatta guariba clamitans (n 5) in the southern states of Brazil (Santa Catarina and Rio Grande do Sul), we identified samples positive for Mansonella perstans in two specimens of A. guariba clamitans. A fragment of 578 bp from the ITS intergenic region (5.8S-ITS2-28S) was targeted for an initial PCR screening. Subsequently, positive samples were subjected to other PCR assays targeting a fragment of the 12S and the 18S genes. This is the first record of molecular detection of the agent in this host in the Pampa Biome. With a wide distribution across Brazil and Argentina, these primates may represent a potential wild reservoir for the zoonotic agent of mansonellosis. Entomological and transmission studies are essential to avoid the urbanization of mansonellosis and to understand the cycles of agents in different environmental scenarios.

First record of melanism in the critically endangered Pampa cat (Leopardus munoai), an endemic species of the Pampa grasslands / Primeiro registro de melanismo no criticamente ameaçado gato-pampeano (Leopardus munoai), uma espécie endêmica das áreas abertas do Pampa

Abstract We report the first record of a melanistic individual of the critically endangered Pampa cat (Leopardus munoai), from July 8th, 2021, at 10:45 am (coordinates 30.096288° S; 54.941139° W) in the area of the Brazilian army, known as Campo de Instrução Barão de São Borja (CIBSB), popularly known as Saicã.

Resumo: Este trabalho reporta o primeiro registro de melanismo do criticamente ameaçado de extinção gato-pampeano (Leopardus munoai), realizado em 8 de julho de 2021, às 10:45 da manhã. O registro foi obtido nas coordenadas 30.096288° S; 54.941139° W na área do exército brasileiro Campo de Instrução Barão de São Borja (CIBSB), popularmente conhecida como Saicã.

Preformulation screening of lipids using solubility parameter concept in conjunction with experimental research to develop ceftriaxone loaded nanostructured lipid carriers

Abstract Development of ceftriaxone loaded nanostructured lipid carriers to increase permeability of ceftriaxone across uninflamed meninges after parenteral administration. Lipids were selected by theoretical and experimental techniques and optimization of NLCs done by response surface methodology using Box-Behnken design. The Δδt for glyceryl monostearate and Capryol90 were 4.39 and 2.92 respectively. The drug had maximum solubility of 0.175% (w/w) in glycerol monostearate and 2.56g of Capryol90 dissolved 10mg of drug. The binary mixture consisted of glyceryl monostearate and Capryol90 in a ratio of 70:30. The optimized NLCs particle size was 130.54nm, polydispersity index 0.28, % entrapment efficiency 44.32%, zeta potential -29.05mV, and % drug loading 8.10%. In vitro permeability of ceftriaxone loaded NLCs was 5.06x10-6 cm/s; evidently, the NLCs pervaded through uninflamed meninges, which, was further confirmed from in vivo biodistribution studies. The ratio of drug concentration between brain and plasma for ceftriaxone loaded NLCs was 0.29 and that for ceftriaxone solution was 0.02. With 44.32% entrapment of the drug in NLCs the biodistribution of ceftriaxone was enhanced 7.9 times compared with that of ceftriaxone solution. DSC and XRD studies revealed formation of imperfect crystalline NLCs. NLCs improved permeability of ceftriaxone through uninflamed meninges resulting in better management of CNS infections.

Native Fauna of Tardigrades from Two Natural Areas of the Argentina Republic.

Understanding and preserving biodiversity in natural habitats is crucial due to their rapid degradation and destruction. The meiofauna of natural areas is less well known than the macroscopic life. Tardigrades are common in limno-terrestrial meiofauna and can indicate environmental conditions. In this study, we expand our understanding of the taxonomy and ecology of tardigrade communities in two natural reserves in Argentina by examining the environmental factors that can affect them and the species that could be used as indicators. In 2018, sampling occurred in the Parque Luro Provincial Reserve (province of La Pampa) and the Poligono A Municipal Ecological Reserve (province of Salta). Samples were taken from epiphytic communities that grow on the bark of trees. Various environmental and microhabitat factors were taken into account. In the province of La Pampa, there were 1326 specimens of five species, and in the province of Salta, there were 212 specimens of nine species. The tardigrade communities in Salta exhibited statistically higher diversity than those in La Pampa. Temperature and moisture affected the tardigrade community of Parque Luro Provincial Reserve, while the microhabitat thickness affected those of Poligono A Municipal Ecological Reserve. The species turnover shaped the community of Salta, while nesting shaped the community of La Pampa.

High Atmospheric CO2 Concentration Mitigates Drought Effects on Acanthostyles buniifolius an Important Grassland Weed in South America.

The differential growth and yield response of plant species to rising carbon dioxide concentrations and climatic change may alter species diversity within biomes. The Pampa Biome in South America is an important grassland biome of agronomic and environmental importance. Acanthostyles buniifolius (Chirca) is one of the most important weeds in natural pasture areas widely distributed in southern South America and can adversely affect livestock production. The current study was designed to identify possible responses of Chirca to CO2 concentration ([CO2]) and drought that would indicate higher adaptation and potential proliferation within the Pampa Biome. Chirca plants were cultivated at two CO2 concentrations (400 (a[CO2]) and 700 (e[CO2]) µmol mol-1) and two water conditions (under water restriction-15% of the pot capacity; and plants without water restriction-pot capacity). Besides growth parameters, we also determined water potential (ѱw), relative water contents (RWC), proline, glycine betaine, total soluble sugars, hydrogen peroxide, lipid peroxidation, superoxide dismutase (SOD), ascorbate peroxidase (APX) activity, chlorophyll A and B, carotenoids and root dry mass (RDM). Plants exposed to e[CO2] are more efficient in water use and have a greater increase in root dry mass, enabling greater adaptation to climate-induced droughts. Among the biochemical changes observed in the plants under drought stress, the accumulation of proline, glycine betaine, and total soluble sugars were the most evident mechanisms allowing plants to tolerate drought stress by osmotic adjustment.

Nueva colonia reproductiva del gaviotín peruano (Sternula lorata) en la costa sur de Perú / New breeding colony of the Peruvian Tern (Sternula lorata) in southern coast of Peru

Resumen En la presente nota se describe la existencia de una nueva colonia reproductiva de Sternula lorata en Pampa El Palo, ubicado en el distrito y la provincia de Ilo, departamento de Moquegua. Entre agosto de 2016 y marzo de 2017 se registraron de 8 a 324 S. lorata y se encontraron 12 nidos activos. El área reproductiva comprende unas 600 ha y se caracteriza por ser una zona abierta con suelo de tipo arenoso y presencia de conchuelas. Esta especie enfrenta algunas amenazas antrópicas en el lugar, tales como el tránsito de vehículos motorizados, el paso de pescadores locales y la presencia de perros domésticos.

Abstract This note describes the existence of a new reproductive colony of Sternula lorata in Pampa El Palo, located in the district and province of Ilo, department of Moquegua. Between August 2016 and March 2017, 8 to 324 S. lorata were recorded and 12 active nests were found. The reproductive area comprises about 600 ha and is characterized by being an open area with sandy-type soil and the presence of shells. This species faces some anthropogenic threats in the area, such as the traffic of motorized vehicles, the passage of local fishermen and the presence of domestic dogs.

Effect of Agroecosystems on Seroprevalence of St. Louis Encephalitis and West Nile Viruses in Birds, La Pampa, Argentina, 2017-2019.

In Argentina, the Pampa ecoregion has been almost completely transformed into agroecosystems. To evaluate the environmental (agricultural area, tree coverage, distance to the nearest water body and urban site) and biological (dove, cowbird, and sparrow abundance) effects on free-ranging bird exposure to St. Louis encephalitis virus (SLEV) and West Nile virus (WNV), we used generalized linear mixed models. For 1,019 birds sampled during 2017-2019, neutralizing antibodies were found against SLEV in samples from 60 (5.8%) birds and against WNV for 21 (2.1%). The best variable for explaining SLEV seroprevalence was agricultural area, which had a positive effect; however, for WNV, no model was conclusive. Our results suggest that agroecosystems in the La Pampa ecoregion increase the exposure of avian hosts to SLEV, thus potentially increasing virus activity.

Revisiting the Tabanid Fauna (Diptera: Tabanidae) of Uruguay: Notes on the Species of the Genus Tabanus Linnaeus, with the Description of a New Species.

We describe a new species of Tabanus (for Uruguay, the first in more than 90 years) based on females from the Department of Tacuarembó, Uruguay. Tabanus tacuaremboensis sp. n. is the 15th species of the genus Tabanus recorded from Uruguay. The species description is accompanied by illustrations of the diagnostic external and internal characters. In addition, for comparison with the new species, we provide photographs of the regional species of Tabanus whose distributions are still poorly known. In view of the lengthy hiatus since the last new tabanid species was described from Uruguay, we offer a brief discussion of the importance of new and further sampling in areas where the tabanofauna is still poorly known.

Neutral and outlier single nucleotide polymorphisms disentangle the evolutionary history of a coastal Solanaceae species.

Speciation begins with the isolation of some individuals or subpopulations due to drivers promoting a diverging genetic distribution. Such isolation may occur, followed by different processes and pressures. Isolation-by-distance (IBD), isolation-by-adaptation (IBA), and isolation-by-colonization (IBC) have been recognized as the main divergence patterns. Still, it is not easy to distinguish which one is the main pattern as each one may act at different points in time or even simultaneously. Using an extensive genome coverage from a Petunia species complex with coastal and inland distribution and multiple analytical approaches on population genomics and phylogeography, we showed a complex interplay between neutral and selective forces acting on the divergence process. We found 18,887 SNPs potentially neutral and 924 potentially under selection (outlier) loci. All analyses pointed that each subspecies displays its own genetic component and evolutionary history. We suggested plausible ecological drivers for such divergence in a southernmost South Atlantic coastal plain in Brazil and Uruguay and identified a connection between adaptation and environment heterogeneity.

Molecular Detection of Trypanosoma kaiowa in Tabanus triangulum (Diptera: Tabanidae) from the Coastal Plain of Rio Grande do Sul, Southern Brazil.

PURPOSE: The species of the genus Trypanosoma are carried and transmitted by horseflies parasitizing a high diversity of vertebrates. In the Coastal Plain of Rio Grande do Sul, southern Brazil, Tabanus triangulum is the most abundant species and, similarly to the other species of horseflies, there is little knowledge about its vector competence. Therefore, this study aimed to screen the field-collected T. triangulum for the presence of Trypanosoma, to estimate infectivity. METHODS: Horseflies were sampled by the Malaise trap in the forest fragments at the coastal plain and DNA was extracted from whole body flies. The Polymerase Chain Reaction was performed. RESULTS: Horseflies presented amplification of 18S ribosomal gene-specific of Trypanosoma species. DNA sequencing and phylogenetic analysis positioned the strains in the Kaiowa clade with Trypanosoma kaiowa, associated with the crocodilian clade of Trypanosoma. CONCLUSION: This study represents the first report of the presence of the Tr. kaiowa in T. triangulum and the expansion of the parasite's range further south in South America.

Does first and last stocking could "fits" Campos grassland structure to improve beef cattle production? / O método de pastoreio rotativo "ponta" e "rapador" pode moldar a estrutura das pastagens naturais para aumentar a produção de bovinos de corte?

This study evaluated the structure of vegetation and the performance of rearing heifers and cull cows in Campos grasslands managed in the rotational stocking method with first-last stocking in the spring-summer period. The treatments were different rest intervals of 402 and 252 degrees-day, which favor the growth of different functional groups of grasses. A completely randomized block design with two treatments and three repetitions was used. The test animals were 24 heifers in the "first" group and 24 cows in the "last" group. In the stratum between tussock grasses, sward heights greater than 0.16 m were predominant in both treatments, it was 1.3 times more frequent in the 402 DD treatment compared to the 252 DD treatment. Average stocking rate was 22% higher in the 252 DD treatment. Although, no differences were observed for the average daily gain of heifers (0.227 kg.day-1) and cows (0.336 kg.day-1) between treatments, the weight gain per area in the experimental period was greater in the 252 DD treatment. Despite the management system with first and last stoking does not provide significant changes in the structure of the pasture, it allowed to achieve satisfactory performance goals in areas of Campos grassland.

Este estudo teve como objetivo avaliar a estrutura da vegetação e o desempenho de novilhas em recria e vacas de descarte em pastagens naturais manejadas em sistema de pastejo rotacionado com lotes "ponta" e "rapador" no período primavera-verão. Os tratamentos foram diferentes intervalos de descanso de 402 e 252 graus-dia (GD), os quais favorecem o crescimento de gramíneas de diferentes grupos funcionais. O delineamento experimental foi em blocos ao acaso com dois tratamentos e três repetições. Os animais de teste foram 24 novilhas no grupo "ponta" e 24 vacas no grupo "rapador". No estrato entre touceiras, as alturas do pasto maiores que 16 cm foram predominantes em ambos os tratamentos, sendo 1.3 vezes mais frequente no tratamento 402 GD em relação ao tratamento 252 GD. A taxa de lotação média foi 22% maior no tratamento com 252 GD. Embora não tenham sido observadas diferenças para o ganho médio diário de novilhas (0,227 kg.dia-1) e vacas (0,336 kg.dia-1) entre os tratamentos, o ganho de peso por área no período experimental foi maior no tratamento 252 GD. Apesar do sistema de manejo com lotes "ponta" e "rapador" não proporcionar mudanças significativas na estrutura da pastagem, ele permite atingir metas de desempenho satisfatórias em áreas de pastagens naturais.

Serosurvey of antibodies against zoonotic pathogens in free-ranging wild canids (Cerdocyon thous and Lycalopex gymnocercus) from Southern Brazil.

The expansion of urbanization on natural areas is increasing contact between human populations with wild animals. Wild carnivores can act as sentinel hosts or environmental health indicators. Thus, the aim of this work was to investigate the exposure of two major species of wild canids from Southern Brazil to selected pathogens. For that, we live-trapped free-ranging Cerdocyon thous and Lycalopex gymnocercus in five localities and determined the frequency of animals with antibodies against Toxoplasma gondii, Trypanosoma cruzi, Leishmania infantum, Neospora caninum, and Leptospira spp. Among the canids sampled, 23% (12/52) (95%CI: 13-36%) had antibodies against T. gondii, with titers ranging from 64 to 512. For T. cruzi, 28% (15/52) (95%CI: 18-42%) of sampled canids were seropositive, with titers ranging from 8 to 64. Concerning the protozoan pathogen N. caninum, a total of 5% (3/52) (95%CI: 2-15%) of wild canids had antibodies against it. None of the sampled canids showed the presence of antibodies against L. infantum. On the other hand, 44% (23/52) (95%CI: 31-57%) of the wild canids showed antibodies against Leptospira spp. The set of results presented here, show that free-ranging neotropical wild canids are exposed and have antibodies against to T. gondii, T. cruzi, Leptospira spp., and to a lesser degree to N. caninum. We found no evidence of L. infantum circulation among the studied populations. These results highlight some of the major pathogens which may represent risks for populations of these wild canids. DATA AVAILABILITY STATEMENT: The data that support the findings of this study are available from the corresponding author upon reasonable request.

Las epidemias en La Pampa (Argentina), en perspectiva histórica* / The epidemics in La Pampa (Argentina), from a historical perspective

Resumen Este artículo describe el inicio de las preocupaciones sanitarias vinculadas a las epidemias ocurridas durante el siglo XX en La Pampa, provincia argentina. Las epidemias, como las de la viruela, fueron un estímulo para estas políticas que frecuentemente tuvieron origen en Buenos Aires, la capital del país. El contagio de muchas epidemias dependía de carencias de infraestructura: agua, desagüe y desecho adecuado de basuras, de la ausencia de un número suficiente de trabajadores de salud, de la presencia de vectores transmisores de enfermedades como los mosquitos y, en última instancia, de la pobreza. La experiencia histórica descrita en este texto resalta la importancia de analizar el impacto del SARS-CoV-2 más allá de las grandes ciudades.

Abstract This article describes the emergence of health concerns relating to the epidemics that occurred during the twentieth century in La Pampa, a province in Argentina. Epidemics such as smallpox drove such policies, which frequently originated in Buenos Aires, the country's capital. The spread of many epidemics was due to shortages: water, sewage and adequate refuse disposal, an insufficient number of health care workers, the presence of disease transmission vectors such as mosquitos, and, ultimately, poverty. The historical experience described in this text highlights the importance of analyzing the impact of SARS-CoV-2 beyond the big cities.

Chemical characterization and antimicrobial activity of Campomanesia aurea against three strains of Listeria monocytogenes / Caracterização química e atividade antimicrobiana de Campomanesia aurea contra três cepas de Listeria monocytogenes

The essential oil (EO) composition of leaves of Campomanesia aurea was analyzed by GC-MS. The plant was collected in April (EOA) and October (EOO) in São Francisco de Assis/RS. The essential oils were obtained by hydrodistillation in a modified Clevenger apparatus. The yields were 4.44% in April, and 6.15%, in October. Thirty-one compounds were identified in EOA, accounting for 96.87% of the total, and twenty-eight compounds were identified in EOO, accounting for 99.46% of the total. For EOA, the major identified monoterpene was p-cymene (8.33%) and the major identified sesquiterpene was alpha-cadinol (10.72%), while regarding EOO the major identified monoterpene was repeatedly Terpinolene (3.43%), whereas the major identified sesquiterpene was alpha-cadinol (12.79%). The antibacterial activity of the essential oil was evaluated against the three Listeria monocytogenes from the American Type Culture Collection (strains ATCC 7644, 19114 and 13932). The essential oil showed a MIC of 10 mg/mL against the strains ATCC 7644 and 19114, with bacteriostatic effect of 20 mg/mL and a MIC of 20 mg/mL for ATCC 13932. Regarding the antibiofilm activity, o EOO showed the best results with an inhibition of 90% in the sessile growth with an applied concentration of 4.0 mg/mL.(AU)

O óleo essencial (EO) das folhas de Campomanesia aurea foi analisado por CG-EM. O A planta foi coletada em abril (OEA) e outubro (OEO) em São Francisco de Assis/RS. Os óleos essenciais foram obtidos por hidrodestilação em aparelho Clevenger modificado. Os rendimentos foram de 4,44% em abril e 6,15% em outubro. Trinta e um compostos foram identificados no EOA, representando 96,87% do total, e vinte e oito compostos foram identificados no EOO, representando 99,46% do total. Para EOA, o principal monoterpeno identificado foi o p-cimeno (8,33%) e o principal sesquiterpeno identificado foi o alfa-candinol (10,72%), enquanto o EOO o maior monoterpeno identificado foi repetidamente Terpinolene (3,43%), enquanto o sesquiterpeno principal identificado foi alfa-cadinol (12,79%). A atividade antibacteriana do óleo essencial foi avaliada contra as três cepas de Listeria monocytogenes obtidas a partir da American Type Culture Collection (isolados ATCC 7644, 19114 and 13932). O óleo essencial apresentou uma CIM de 10 mg/mL contra as cepas ATCC 7644. e 19114, com efeito bacteriostático de 20 mg/mL e MIC de 20 mg/mL para ATCC 13932. Quanto à atividade antibiofilme, o EOO apresentou os melhores resultados com uma inibição de 90% no crescimento séssil com uma concentração aplicada de 4,0 mg/mL.(AU)

Chemical characterization and antimicrobial activity of Campomanesia aurea against three strains of Listeria monocytogenes / Caracterização química e atividade antimicrobiana de Campomanesia aurea contra três cepas de Listeria monocytogenes

Abstract The essential oil (EO) composition of leaves of Campomanesia aurea was analyzed by GC-MS. The plant was collected in April (EOA) and October (EOO) in São Francisco de Assis/RS. The essential oils were obtained by hydrodistillation in a modified Clevenger apparatus. The yields were 4.44% in April, and 6.15%, in October. Thirty-one compounds were identified in EOA, accounting for 96.87% of the total, and twenty-eight compounds were identified in EOO, accounting for 99.46% of the total. For EOA, the major identified monoterpene was p-cymene (8.33%) and the major identified sesquiterpene was α-cadinol (10.72%), while regarding EOO the major identified monoterpene was repeatedly Terpinolene (3.43%), whereas the major identified sesquiterpene was α-cadinol (12.79%). The antibacterial activity of the essential oil was evaluated against the three Listeria monocytogenes from the American Type Culture Collection (strains ATCC 7644, 19114 and 13932). The essential oil showed a MIC of 10 mg/mL against the strains ATCC 7644 and 19114, with bacteriostatic effect of 20 mg/mL and a MIC of 20 mg/mL for ATCC 13932. Regarding the antibiofilm activity, o EOO showed the best results with an inhibition of 90% in the sessile growth with an applied concentration of 4.0 mg/mL.

Resumo O óleo essencial (EO) das folhas de Campomanesia aurea foi analisado por CG-EM. O A planta foi coletada em abril (OEA) e outubro (OEO) em São Francisco de Assis/RS. Os óleos essenciais foram obtidos por hidrodestilação em aparelho Clevenger modificado. Os rendimentos foram de 4,44% em abril e 6,15% em outubro. Trinta e um compostos foram identificados no EOA, representando 96,87% do total, e vinte e oito compostos foram identificados no EOO, representando 99,46% do total. Para EOA, o principal monoterpeno identificado foi o p-cimeno (8,33%) e o principal sesquiterpeno identificado foi o α-candinol (10,72%), enquanto o EOO o maior monoterpeno identificado foi repetidamente Terpinolene (3,43%), enquanto o sesquiterpeno principal identificado foi α-cadinol (12,79%). A atividade antibacteriana do óleo essencial foi avaliada contra as três cepas de Listeria monocytogenes obtidas a partir da American Type Culture Collection (isolados ATCC 7644, 19114 and 13932). O óleo essencial apresentou uma CIM de 10 mg/mL contra as cepas ATCC 7644. e 19114, com efeito bacteriostático de 20 mg/mL e MIC de 20 mg/mL para ATCC 13932. Quanto à atividade antibiofilme, o EOO apresentou os melhores resultados com uma inibição de 90% no crescimento séssil com uma concentração aplicada de 4,0 mg/mL.