Northeast Argentina Research Articles

Modeling of leptospirosis outbreaks in relation to hydroclimatic variables in the northeast of Argentina

The transmission of leptospirosis is conditioned by climatic variables. In northeastern Argentina leptospirosis outbreaks occur mainly in coincidence with periods of abundant precipitation and high hydrometric level. A Susceptible-Infectious-Recovered Epidemiological Model (SIR) is proposed, which incorporates hydroclimatic variables for the three most populated cities in the area (Santa Fe, Paraná and Rosario), during the 2009–2018 period. Results obtained by solving the proposed SIR model for the 2010 outbreak are in good agreement with the actual data, capturing the dynamics of the leptospirosis outbreak wave. However, the model does not perform very well in the last months of the year when isolated cases appear outside the outbreak periods, probably due to non- climatic factors not explicitly considered in the present version of the model. Nevertheless, the dynamic modeling of infectious diseases considering hydroclimatic variables constitutes a climatic service for the public health system, not yet available in Argentina.

First record of Oldenlandia corymbosa (Spermacoceae-Rubiaceae), a new alien species for Paraguay and Argentina

Background and aims: During the revision of the southern South American species of Oldenlandia, populations of O. corymbosa were found in Paraguay and Argentina. The aim of this contribution is to report the presence of this adventitious species to the Paraguayan and Argentinian flora for the first time. M&M: Living plants and herbarium material, as well as the original description of Oldenlandia corymbosa were analysed. Taxonomic and morphological analyses were performed. Collected materials were deposited in the FCQ and CTES. Results: A description of the morphology of the species and habitat based on herbarium specimens and field observations are provided, along with an illustration, photographs, and a map indicating the geographical position of the recorded populations in the Northeast and South Paraguay and Northeast Argentina in the Corrientes province. Complementary, an identification key of Oldenlandia species occurring in Argentina and Paraguay is provided. Conclusion: With the record of Oldenlandia corymbosa in Paraguay and Argentina, the range of distribution of this non-native species is extended up to the Southern Cone of South America. Its naturalized status in Paraguay raises the possibility that it was, until now, overlooked in other regions of the Northeast Argentina.

Vortex Storms in the West of Santa Catarina

The objective of this work is to analyze the occurrence or not of tornadoes in the city of Guatambu, state of Santa Catarina (SC), southern Brazil, at the end of the night of 13, at dawn on September 14, 2021. Alerts by the official agencies of the region of the probable occurrence of tornadoes and strong storms in the area between the northeast of Argentina, Uruguay and Rio Grande do Sul. A tornado is the most violent windstorm on earth. The tornado is a rotating column of air that extends from a cloud to the ground. The analysis of satellite maps indicated the occurrence of storms, with probable formation of tornadoes in the municipality of Guatambu. Thus, confirming reports from residents, official bodies such as the Civil Defense of Santa Catarina, and the state's meteorological system. It is likely that the formation of a tornado in the municipality of Guatambu occurred between 01:20 UTC on and 02:10 UTC on Sep 14, 2021.

Climatic suitability and compatibility of the invasive Iris pseudacorus L. (Iridaceae) in the Southern Hemisphere: Considerations for biocontrol

Iris pseudacorus L. (Iridaceae) is an emergent macrophyte native to Europe, North Africa and western Asia. Considered invasive in wetland habitats around the world, this species is now the target of a biocontrol programme in the Southern Hemisphere. Native range surveys of the weed led to the selection of the flea beetle, Aphthona nonstriata Goeze (Coleoptera: Chrysomelidae), as a candidate biocontrol agent. An important aspect to consider in weed biocontrol is the ability of an agent to establish and thrive in the environment where it is released. Climatic incompatibility between source and intended release sites can in fact limit the success of a biocontrol programme. In the current study, the potential climatic niche of I. pseudacorus and A. nonstriata in the Southern Hemisphere was analysed. The ecological niche modelling software MaxEnt was used to map the climatic suitability of both organisms across invaded regions in South America, southern Africa and Australasia. Furthermore, occurrence records from each invaded range were used independently to model the climatic compatibility of I. pseudacorus in Europe, in order to prioritize areas of the native range to explore during future surveys for potential biocontrol agents. The models identified areas at high risk of invasion by I. pseudacorus in northern Argentina, Uruguay, southern Brazil and central Chile, as well as numerous provinces of eastern South Africa, Lesotho, southern Australia and New Zealand. Accordingly, the highest climatic suitability for A. nonstriata was predicted across the humid temperate climates of north-east Argentina, Uruguay, southern Brazil, southern South Africa, south-east Australia and New Zealand. These results can eventually be used in future release plans to prioritize areas where establishment and survival of the agent is expected to be highest. At the same time, it may be useful to search the native range of the weed for biological control agents showing high climatic adaptation towards the intended release sites of each invaded range. In this regards, our climatic compatibility models identified high-priority areas across the Mediterranean regions of Italy and southern France, as well as the temperate regions of central and western Europe. Altogether, the current study provides useful new information to tackle the invasion and advance the biocontrol programme of I. pseudacorus in the Southern Hemisphere.

Diagrammatic scale for quantification of severity of white thread blight disease in yerba mate (Ilex paraguariensis Saint Hilaire).

The yerba-mate industry is one of the most important economic activities in Misiones, a province in the northeast of Argentina that is the world's leading producer and exporter of this crop. White thread blight disease caused by Ceratobasidium niltonzousanum affects the cultivation reducing its quality and productivity. Due to the lack of a standardized visual method to quantify the severity of this disease in yerba mate, a diagrammatic scale was developed and validated. Yerba-mate branches were collected in a field in the north of Misiones province, and the actual severity was determined digitally. A six-level scale was developed using the DOSLOG software, based on the Weber-Fechner law. The validation was carried out by twenty raters. One evaluation without the diagrammatic scale and two evaluations with the scale were carried out in 14-day intervals. Accuracy, precision, and reproducibility of the scale were evaluated through linear regressions and correlation analysis, obtaining R2 values ranged between 0.70 and 0.94. Using the diagrammatic scale developed in this work, raters enhanced the accuracy and precision of the estimates, and the repeatability of the scale improved by 94.74%. The scale was appropriate to assess the damage of white thread blight in yerba mate.

Home range patterns of Helmeted Woodpecker (Celeus galeatus), Lineated Woodpecker (Dryocopus lineatus), and Robust Woodpecker (Campephilus robustus) in Misiones, Argentina, in a global perspective

Home range mapping studies of birds inform about area requirements and responses to land management as reflected by home range sizes and by resource selection within home ranges. Tracking studies of woodpeckers (<em>Picidae</em>) so far have been concentrated in temperate regions. In the subtropical Atlantic Forest of northeast Argentina, we assessed interspecific differences in home range sizes in old-growth forests and selectively logged forests of Helmeted Woodpecker (<em>Celeus galeatus</em>, a globally threatened species), Lineated Woodpecker (<em>Dryocopus lineatus</em>), and Robust Woodpecker (<em>Campephilus robustus</em>). Helmeted Woodpecker had larger breeding home ranges in selectively logged forests, averaging 105 ± 39 ha for pairs, versus 60 ± 13 ha in old-growth forests. Lineated Woodpecker breeding home ranges of pairs averaged 56 ± 22 ha, and those of Robust Woodpecker 43 ± 22 ha, with no differences between forest types. Helmeted Woodpeckers had an unusual separation between the home ranges of males and females in breeding pairs, with a mean area overlap of only 8% ± 9% near the nest tree, resulting in large home ranges for pairs. Helmeted Woodpecker and Robust Woodpecker individuals that were followed into the post-breeding stage had marked expansions of their home range sizes relative to breeding home ranges. To place our findings with Atlantic Forest woodpeckers in perspective we reviewed whether woodpecker home range sizes increase with latitude and body mass globally. For 29 populations of 22 woodpecker species, a power regression model with these factors explained 24.1% of variation in breeding home range sizes, with 17.1% of variation explained by latitude alone. Woodpecker species with larger home ranges than predicted values were three species of North American woodpeckers of coniferous forests, as well as the Helmeted Woodpecker. Our results of smaller home ranges in old-growth forests for the Helmeted Woodpecker affirm an association of this species with such forests. We urge the conservation of the few remaining tracts of old-growth Atlantic Forest and more restoration of logged forests to mature conditions.

A comprehensive approach using multiple biomarkers to detect damage induced by pesticides in broad-snouted caiman (Caiman latirostris) under ex-situ conditions

Caiman latirostris is one of the two species of the order Crocodylia that inhabit Argentina and is considered a species of vital ecological and economic importance in the north-east of Argentina. In this region, pesticides are the most common contaminants in natural environments and wild caiman populations are subject to this contamination constantly. The aim of this study was to evaluate the effects the main pesticides used in the region: glyphosate (GLY), cypermethrin (CYP) and chlorpyrifos (CPF) -based formulations, as well as the mixture of them, on C. latirostris juveniles under semi-controlled condition of exposure (ex-situ) during 75 days. One hundred yearling caimans (10-month-old) were equally distributed into five experimental groups (20 animals per group): a negative control (NC -tap water), GLY 2% (Roundup® Full II formulation -RU), CYP 0.12% (Atanor® formulation), CPF 0.8% (Lorsban® formulation), and a mixture of the three pesticides (Mx3: GLY 2% + CYP 0.12% + CPF 0.8%). We applied early warning biomarkers to detect damage induced by these chemicals in peripheral blood: activity of the antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD), analysis of lipid peroxidation (LPO) by the thiobarbituric acid reactive substances (TBARS), DNA damage and specific base oxidation through the standard and modified comet assay (CA), chromosome damage by micronucleus (MN) test and other nuclear abnormalities (NAs), hematological and growth parameters. Results showed a statistically significant increase in MN and NAs frequency, DNA damage, with an important contribution of base oxidation for all exposed groups compared to the NC. Total white blood cells count (TWBCC), and growth parameters showed effects mainly at the Mx3. The principal component analysis (PCA) demonstrated more sensitivity for biomarkers associated to genetic damage, including base oxidation to DNA than LPO, antioxidant enzyme modulation, immunotoxicity or growth parameters, to detect pesticides effects, applied under conditions similar to that found in natural environments.

A narrative of suffering and soil: Swedish migration and settler colonialism in northeast Argentina

ABSTRACT This article examines the narrated memory of a Swedish settler colony in northeast Argentina. Recently, scholarly attention has turned to how migrants of the nineteenth and early twentieth centuries contributed to colonizing processes in the Americas as they established themselves on lands already inhabited by Indigenous Peoples. The settlement of Swedish migrants in Misiones is here regarded as part of a strategy of settler colonialism advocated by the Argentine state in order to extend the agrarian frontier further and thereby ‘civilise’ and secure the nation’s rural landscape through the presence of white settlers. From this perspective, the aim of the article is to understand how the historical macropolitical framework of settler colonialism in Argentina is interwoven in the collective and individual narratives of Swedish descendants in present-day Misiones. The article draws on ethnographic interviews and observations made in Misiones between 2017 and 2019. Semi-structured interviews were conducted with 34 individuals along with walk-along observations at seven Swedish community sites. The article argues that a central narrative of memory among the descendants of Swedish settlers relies upon certain elements crucial to settler colonial societies. However, while this narrative structure is intrinsic to settler colonialism, it must also be analysed as part of a migration narrative. This article brings forth new empirical material from a site in Latin America where Swedish migration history has not previously been studied ethnographically. Further, it brings the study of migration, colonial settlement, and indigenous dispossession together through its analysis of a settler narrative in the particular context of settler colonial history of Misiones.

Flood depth-damage and fragility functions derived with structured expert judgment

Depth-damage relationships of residential typologies have an important bearing on the reliability of flood risk assessments. Yet, the information for creating adequate functions is frequently missing in places where they are needed the most: developing countries where floods inflict severe losses. To overcome the lack of site-specific functions, modelers usually adopt functions from foreign typologies, extrapolate from limited flood damage data, and conduct expert-elicitation surveys. The latter, although not exempt from challenges, are a helpful resource in situations in which there are sufficient experts available. The classical model is a structured expert judgment technique which is one of the most used because it minimizes the number of subjective elements in the ranking of experts’ experience and its results can be compared with similar studies. This paper presents depth-damage and fragility functions developed with the classical model conducted with experts with extensive knowledge in the flood damage mechanism of typologies in northeast Argentina—a region under a severe flood hazard. The depth-damage functions were partially validated with damage data and exhibited good agreement, also they are consistent with the fragility functions. Hence, these functions can be helpful for probabilistic flood risk assessments, provided that the underlying assumptions are deemed acceptable.

Relevance of Trixis divaricata Essential Oil in the Inhibition of the Coagulant Activity of Bothrops diporus Venom

Snakebite accidents are part of the neglected tropical diseases (NTDs) that affect millions of people in tropical and subtropical areas of the world, so an ethnopharmacological approach is needed to identify the secondary metabolites necessary for their treatment. Particularly the accident produced by the highly venomous snakes of Bothrops genus is characterized by blood coagulation disorders due to the existence of thrombin-like enzymes. Considering that Trixis divaricata (Kunth) Spreng. ssp. divaricata (Asteraceae) is used as antivenom in Northeast of Argentina, our interest was to determine its efficacy for the treatment of this problem. The inhibition of coagulant activity of T. divaricata extracts and essential oil was evaluated against Bothrops diporus venom. In addition, to characterize the metabolic behavior of this species, the chemical profile of the essential oil was studied., since it was the one that presented the highest inhibitory activity. The results showed that the essential oil is the most active in inhibiting the coagulant activity of Bothrops venom (about 80 %), while only the hexane extract of the leaves presents some activity. The composition of the essential oil in different vegetative stages was studied and no significant differences were found.

Ecology of fleas and their hosts in the trifinio of north‐east Argentina: first detection of Rickettsia asembonensis in Ctenocephalides felis felis in Argentina

Fleas are important in public health due to their role as parasites and vectors of pathogens, including Rickettsia. The aim of this study was to evaluate the diversity, abundance and prevalence of fleas and the presence of Rickettsia in the trifinio of north-east Argentina. Fleas from household and synanthropic animals were obtained from urban and periurban areas. They were taxonomically identified and samples of 227 fleas in 86 pools were analysed by polymerase chain reaction targeting the gltA and ompB genes of Rickettsia spp. The study revealed that Ctenocephalides felis felis was dominant on dogs, cats and opossums, with higher prevalence in the periurban area. The Shannon-Wiener and Morisita-Horn indices expressed differences in the diversity and similarity values of the absolute abundances of the species between the areas compared. DNA amplifications revealed 30.8% C. f. felis pools positive for Rickettsia spp. Phylogenetic analysis showed that the haplotype obtained was identical to Rickettsia asembonensis from Peru and Brazil. This is the first detection in Argentina of R. asembonensis that infects C. f. felis, and we emphasize the importance of conducting research from a 'One Health' perspective on the role of opossums and rodents in the integration of the transmission cycles of rickettsial bacteria.

Hatching pattern and coexistence of Aedes aegypti and Aedes albopictus (Culicidae) in a subtropical city, Argentina, after three decades of coexistence

Aedes aegypti and Aedes albopictus are mosquito vectors of numerous arboviruses of sanitary importance. Presently in Argentina, neither Ae. aegypti nor Ae. albopictus, have displaced the other species in the places where they coexist, since the introduction of the latter in 1998. In this study, we evaluated whether these species coexist at different scales (ovitrap, microhabitat and habitat) in the city of Eldorado, Misiones province, northeast Argentina. We also analyzed the seasonal variation and climate variables related to the delay in egg hatching of both species. Mosquitoes were collected weekly, from June 2017 to May 2018, using ovitraps placed in urban areas. We conclude that Ae. aegypti and Ae. albopictus coexist in the study area, at the ovitrap, microhabitat and habitat scales. Furthermore, no pronounced pattern of delayed hatching has been observed for either species; however, eggs of Ae. albopictus laid during colder weeks and less rainfall needed a greater number of immersions to hatch, while for Ae. aegypti those laid during weeks with low rainfall and high temperatures showed the longest delay in hatching response.

Archaeological palynology of a Quaternary coastal plain in southernmost Brazil

Discussions on the relationships between human groups and the environment are recurring Archaeology topics around the world. In South America, there is a specific kind of archaeological site called “earthen mound”, locally known as “cerritos de indios” that is ethnically linked to the Charrua and Minuano groups. They mainly cover southernmost Brazil (state of Rio Grande do Sul), Uruguay, and northeast Argentina. The study of the formative processes of these sites and their relationship with former inhabitants reveal distinct morphological and cultural characteristics in the context of each earthen mound occurrence. Thus, palynological studies associated with interdisciplinary research are important tools for understanding the environmental, and cultural dynamics of mound-builders. Within this context, this study presents new data on the formative processes and role of southern Brazilian earthen mounds by combining palynological, sedimentological, and chemical analyses. The analyses were performed on the earthen mound PSG-02 and adjacent area sediments, located on the southernmost Brazilian coastal plain, in a wetland called Pontal da Barra, at the estuary of Patos Lagoon. It was possible establish some relationships between its ancient occupation and the environmental dynamics and identify the influence of numerous environmental factors on their social dynamics. The earthen mound PSG-02, dated between 1280 ± 20 and 1859 ± 29 years BP, would probably be in a multifunctional context and was strategically located for gathering of natural resources as well as a dwelling and a funerary monument. Our findings are fundamental for understanding the interactions between earthen mound communities and the environment, filling another behavioral evolution gap of particular past human groups.

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Stauroneis schinzii var. argentina and S. schinzii var. maxima were first described from Esteros del Iberá, a large subtropical wetland located in northeast Argentina. The type materials of these varieties were examined with light and scanning electron microscopy and compared to S. schinzii var. schinzii and other infraspecific taxa. As a result of this study the taxonomic validity of both varieties was confirmed, their diagnosis were emended based on the new morphological information derived, and lectotypes and isolectotypes were designated.

Fluorescent polarization assay, two versions of indirect and competitive enzyme- linked immunoassay for brucellosis diagnosis in vaccinated buffaloes (Bubalus bubalis)

ABSTRACT: The fluorescence polarization assay (FPA), two variants (V) of the indirect enzyme-linked immunosorbent assay (I-ELISA) and the competitive enzyme-linked immunosorbent assay (C-ELISA) were evaluated in buffaloes to detect antibodies against Brucella spp. The V1 of I-ELISA identifies them through the monoclonal (M23) anti-bovine IgG (I-ELISAM23) and the V2 through the ProteinA / G (I-ELISA-A/G). Serum samples of 862 buffaloes (Bubalus bubalis) from the Northeast of Argentina (NEA) were analyzed using the complement fixation test (CFT) as the reference. Receiving Operator Characteristic (ROC) analysis defined for the area under the curve (AUC) determined the cutoff points, sensitivity (Se) and specificity (Sp) for each test. CFT identified 107 positive and 755 negative sera. The best AUC (0.986), Concordance with CFT (96.3%) and kappa value (0.843) was obtained by I-ELISA A/G test. This assay showed the highest Se (95.33%) and C-ELISA the highest Sp (97%). FPA failed to measure the antibodies in 23 (2.65%) serum samples due to unsuccessful reading. I-ELISA M23 proved to be ineffective to diagnose brucellosis in bubaline sera. The four serological tests showed cutoff points lower than those standardized for bovines. As conclusion, I-ELISA A/G, C-ELISA and FPA with its limitations would be effective techniques for the diagnosis of brucellosis in buffaloes in the NEA, requiring an appropriate cut-off point to guarantee their maximum performance in this species.

Hassalstrongylus dollfusi (Nematoda, Heligmonellidae): rediscovery in native South American rodents, six decades after its description.

Hassalstrongylus dollfusi (Díaz-Ungría, 1963) Durette-Desset, 1971 was described in a wild house mouse, Mus musculus, from Venezuela and, since then, has never been reported again in the type host or in any other host. In this work, specimens assignable to H. dollfusi were found at 10 localities in Northeast Argentina, in five species of sigmodontine rodents. The nematodes were attributed to H. dollfusi based on diagnostic characters such as: synlophe with 22–31 subequal ridges; in males, hypertrophy of right ray 4 of the male bursa, thickening of the dorsal ray and bases of rays 8, distal tip of the spicules bent and spoon shaped; and, in females, presence of subventral postvulvar alae supported by hypertrophied struts. The new host recorded are: Oligoryzomys fornesi, O. flavescens, O. nigripes, Holochilus chacarius and Akodon azarae. The parasite showed a strong preference for host species of Oligoryzomys, which appear to act as primary hosts. The parasite could be present, parasitizing different species of Oligoryzomys, in a geographic area from the type locality in Venezuela southward to north Corrientes in Argentina. It has not been reported from populations of Oligoryzomys spp. of the Argentinean and Brazilian Atlantic Forest, nor south of 28° S, which may be explained by constraints in the environmental conditions required by the free-living stages of the parasite. This study provides the first identification and redescription of H. dollfusi in southern South America, from autochthonous hosts, six decades after its description.

Natural distribution of yerba mate in Brazil in the current and future climatic scenarios

Ilex paraguariensis St. Hill is a native species from Brazil, northeast of Argentina and Paraguay. It is mainly used in mate tea, a drink prepared by infusion of leaves. Nowadays, the species has sparked interest in its potential nutraceutical capacity and the presence of bioactive compounds for pharmacological and cosmetic use. The natural distribution area of the species is directly related to the climate. Thus, the predictability of occurrence, using appropriate niche models, is an important tool to assist in the adoption of species conservation strategies. Accordingly, aim of this work was to identify the natural distribution of the species, using ecological niche models, and project its distribution in future climatic scenarios, according to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. A tendency toward significant reduction in areas favorable to the distribution of yerba mate has been projected for future climatic scenarios, either “moderately pessimistic” (RCP4.5) or “more pessimistic” (RCP8.5), 71.7 and 78% in 2050 and 87 and 96.4% in 2070, respectively, showing a resultant trend toward concentration in the higher altitudes of the Atlantic Forest Biome. Thus, it is possible to predict the more favorable areas for conservation and breeding programs, ensuring the maintenance of its (da erva-mate) genetic diversity and resilience.

Neoliberalismo y políticas públicas fragmentarias en el Centro-Oeste de Formosa, Nordeste Argentino

El presente trabajo tiene como objetivo analizar el proceso de plegamiento fragmentario de las políticas públicas productivistas, en el espacio territorial del Centro-Oeste de la provincia de Formosa (Nordeste Argentino), entre los años 1990 y 2015. La metodología que se sigue se apoya en distintas fuentes documentales, que dan cuenta de dicho proceso. A través de este análisis, se observa cómo la dinámica de plegamiento fragmentario de las políticas públicas productivistas estructura un patrón regulativo escalar neoliberal, generador de relaciones asimétricas de poder, en lo político, económico, y social. De modo que el territorio en estudio se transforma con la continuidad de desigualdades persistentes.

Aprovechamiento de materias primas regionales para el desarrollo de envases comestibles activos y biodegradables

Entre las tecnologías emergentes para la optimización de la preservación de alimentos surge como novedosa alternativa el empleo de películas o recubrimientos comestibles autosoportados que confieren propiedades funcionales específicas. Los trabajos desarrollados en este tema, conducen a incorporar agentes antimicrobianos de fuentes naturales en la formulación de películas, ya que la inclusión de aditivos podría considerarse como una nueva tendencia de envasado activo. Los films o recubrimientos comestibles son láminas delgadas elaboradas con materiales aptos para el consumo y que actúan como una barrera entre el alimento y el ambiente que los rodea, incrementando así la vida útil del producto. Los films obtenidos a partir de polisacáridos, especialmente de almidones, presentan un alto potencial ya que tienen un bajo costo, son transparentes, no confieren olor ni color, poseen una baja permeabilidad al O2 y son biodegradables. Estos sistemas altamente prometedores son capaces de mejorar la calidad, vida útil, seguridad y funcionalidad de los alimentos, y además pueden actuar como carriers de ingredientes activos. En el presente trabajo, se expone la formulación de recubrimientos comestibles a base de almidón de mandioca y adicionados de aceites esenciales (AE), y su posterior evaluación del efecto antimicrobiano frente a la levadura Zygosaccharomyces parabailii, como antecedente de la investigación realizada en el marco de mi tesis de maestría. Sobre la base de los resultados obtenidos en la misma, se propone el actual plan de tesis doctoral que consiste en desarrollar un envase comestible, activo y ecofriendly a base de almidón de mandioca, glicerol y agua, y analizar la viabilidad de la incorporación de pulpas o concentrados de frutas regionales del Nordeste Argentino (mango, guayaba y mamón), estudiando su influencia en las propiedades físicas, mecánicas, de barrera y como fuente natural de polifenoles, antimicrobianos y antioxidantes.

Obtención y caracterización de fibras vegetales para la mejora nutricional de caramelos tipo gummies: avances de tesis doctoral

Considerando que el sobrepeso es una consecuencia de una malnutrición, que afecta a todos los países de la región y tiene alcance global, es importante mantener una buena alimentación mediante el consumo de alimentos saludables y poco calóricos. Consecuentemente, las investigaciones del área de alimentos se orientan a obtener ingredientes con características funcionales a partir de fuentes naturales, para incorporarlos en alimentos que propicien una dieta balanceada y nutritiva, y que prevengan enfermedades crónicas. Uno de estos componentes funcionales es la fibra dietaria, que se encuentra en una gran variedad de hortalizas como las mandiocas, batatas, y jengibres, cultivados en el Nordeste argentino. Por consiguiente, este plan de tesis doctoral consiste en la reformulación de caramelos tipo gummies con el objeto de mejorarlos nutricionalmente a partir de la adición de fibra extraída de vegetales regionales. La misma actuará, además, como agente estructural debido al reemplazo de los azúcares presentes en la formulación por edulcorantes no calóricos con el fin de reducir del aporte calórico.En este trabajo, se presentarán los avances realizados del mencionado plan, que comenzó a mediados del año 2019 y continua hasta la actualidad. Primeramente, se realizó el ensayo de extracción de fibra dietaria de batata utilizando un método tradicional químico con etanol al 85% (v/v) como solvente, y se determinó el rendimiento. Se definieron los parámetros del proceso tales como las condiciones de pre-tratamiento, temperaturas de extracción y secado, ratio, tiempo de secado y tamaño de tamiz, dando como resultado rendimientos de 10% aproximadamente. Además, se llevaron a cabo las determinaciones de los componentes bioactivos: carotenoides totales y capacidad antioxidante de las materias primas batata, jengibre y mandioca, con el fin de caracterizarlas. En ambos casos se utilizaron métodos espectrofotométricos, y se obtuvieron valores del contenido de carotenoides totales de 14.27±0.55 µgβ-caroteno/gmuestra para el jengibre, y de 12.66±1.43 y 1.35±0.06 µgβ caroteno/gmuestra, para la batata y mandioca. Un comportamiento similar ocurrió en el caso de la capacidad antioxidante donde el jengibre fue un 90% y 50% mayor en comparación con la mandioca y la batata, respectivamente.De este modo, se determinó el rendimiento de la extracción química de fibra a partir de batata, y se observó que el jengibre fue el material vegetal con mayor contenido de compuestos bioactivos, lo que lo hace un ingrediente potencialmente utilizable para lograr la mejora nutricional de los alimentos.