INNOTEC is an open-access journal peer-reviewed by a committee of external reviewers and edited by the Technological Laboratory of Uruguay (LATU). The journal includes original unpublished articles and its frequency is biannual (January-June and July-December) under an ongoing publication basis. The journal's aims are to disseminate and transfer knowledge in the areas of Forestry, Environment, Metrology and Food Technology. INNOTEC is addressed to scholars, researchers and technicians of the Uruguayan and international scientific community.
Laboratorio Tecnológico del Uruguay - LATU
Los autores del manuscrito declaran conocer y aceptar los siguientes términos de responsabilidad: Haber participado lo suficiente en el trabajo como para hacer pública la responsabilidad por su contenido. Que el manuscrito representa un trabajo original que no fue publicado ni está siendo considerado por otra revista para su publicación, en parte o en forma íntegra, tanto impresa como electrónica. Que en caso de ser solicitado, procurará o cooperará en la obtención y suministro de datos sobre los cuales el manuscrito esté basado. Declara que la información divulgada que pudiera pertenecer a un tercero cuenta con la autorización correspondiente. Autorización para la publicación y compromiso de cita de primera publicación Los autores/as conservan los derechos de autor y ceden a la revista INNOTEC / INNOTEC Gestión el derecho de la primera publicación, con el trabajo registrado con la licencia de atribución Creative Commons Reconocimiento-NoComercial 4.0 Internacional. Creative Commons, que permite a terceros utilizar lo publicado siempre que mencionen la autoría del trabajo y a la primera publicación en esta revista sin fines comerciales. El autor se compromete a realizar la cita completa de la edición institucional de esta primer publicación en las siguientes publicaciones -completas o parciales- efectuadas en cualquier otro medio de divulgación, impreso o electrónico. Los autores/as pueden realizar otros acuerdos contractuales no comerciales independientes y adicionales para la distribución no exclusiva de la versión del artículo publicado en esta revista (p. ej., incluirlo en un repositorio institucional o publicarlo en un libro) siempre que indiquen claramente que el trabajo se publicó por primera vez en esta revista. Se permite a los autores/as publicar su trabajo en Internet (por ejemplo en páginas institucionales o personales) antes y durante el proceso de revisión, ya que puede conducir a intercambios productivos y a una mayor y más rápida difusión del trabajo publicado (vea The Effect of Open Access). A su vez los autores/as autorizan al LATU a publicar el trabajo en su repositorio digital. Los conceptos y opiniones vertidos en los artículos son de responsabilidad de sus autores. Este obra está bajo una licencia Reconocimiento-NoComercial 4.0 Internacional.
Results of the first interlaboratory comparison of relative humidity in Panama:
The main objective of interlaboratory comparisons is to evaluate the degree of equivalence between the pilot laboratory and the participating laboratories. In this way it is possible to validate calibration methods, detect opportunities for improvement and make corrections in the measurement systems, among other topics. In the year 2024, during the months of March to August, the first interlaboratory comparison in calibration of relative humidity metrics was carried out in Panama, organized and piloted by the National Metrology Center of Panama (CENAMEP AIP) in the range of 30 to 90 % RH with a reference temperature of 20 °C. Three secondary laboratories in the country and two technicians in training from the Relative Humidity Laboratory (H0) of CENAMEP AIP participated in this intercomparison exercise. For the analysis of the results, the statistical tool of the normalized error was used, which determined that approximately 85 % of the measurements were satisfactory, indicating a good level of agreement between the obtained results and the reference values. This exercise made it possible to implement timely corrective and preventive actions and to reinforce the credibility of the participants with clients, regulatory agencies and other interested parties.
Copyright (c) 2025 Fanny Castro, Ebony Prado, Héctor Acevedo, Julio González Vannucchi, Ángel Alfredo Escorche, Diego Romero Velásquez, Erick Domínguez http://creativecommons.org/licenses/by-nc/4.0
Relationship between forest fires and air quality and rainfall in the Metropolitan Area of Asunción, Paraguay
The forest fires cause significant adverse effects in urban and rural areas. The objective of the study was to evaluate the influence of forest fires on the chemical composition of rainwater and air quality in the Metropolitan Area of Asunción, Paraguay. Rainwater samples were collected in September and November 2024. pH, nitrate (NO₃-) and sulfate (SO₄-2) were analyzed using standardized methods. Air quality was analyzed from June to December 2024 using semi-professional sensors. The results indicated no evidence of acid rain (pH < 5.6). In September, nitrate (11.92 ± 4.98 mg·L-¹) and sulfate (11.38 ± 4.21 mg·L-¹) concentrations were significantly higher (p < 0.05) than those recorded in November (3.78 ± 5.55 mg·L-¹ and 4.33 ± 3.14 mg·L-¹), respectively, suggesting an increased presence of acid precursors (NOₓ and SO₂) in the atmosphere during the fire-affected period. Air quality showed elevated concentrations of PM₂.₅, with critical peaks in early September. These findings underscore the need for integrated atmospheric monitoring and targeted environmental policies to mitigate the effects of forest fires on urban and peri-urban ecosystems.
Copyright (c) 2025 Diana Diez-Pérez-Núñez, Ángel Rincón Rodríguez, Analía Soledad Gamarra Rolón, Aura Micaela Miranda Garcete, Betarram Caballero, María Cielo Núñez Ferreira, Clara Cano, Dorina Catalina Frutos Morales, Francisco Arzamendia, Larisa Monserrath Ibarra Amarilla, Larissa Antonella Coronel Rodríguez, Max Alexander Romero Espinola , Melissa Carolina Figueredo Mendoza, Natasha Antonella Barrios Carrera , Sofía Del Pilar Chamorro Cardozo , Sofía Belén López López, Luz María T. Escobar Núñez, Cristian M. Argüello Llamosas, Marcelo D. López Báez, Tobías M. López-Ramírez, Fátima J. Báez V., Jorge A. Belotto http://creativecommons.org/licenses/by-nc/4.0
The relationship between Mean Fibre Diameter measurements by Airflow and Laserscan for uruguayan wool
Uruguay is recognized for its production of high-quality wool, combining traditional practices with modern technology. Although wool production fell by 3.5 % last year, exports increased by 62.7 %. However, its competitiveness was limited by an International Wool Textile Organisation (IWTO) regulation that required the certification of Mean Fibre Diameter (MFD) using the Airflow method (AF, IWTO-28) (International Wool Textile Organisation, 2013), despite the fact that leading markets utilize the Laserscan (LSN, IWTO-12) (International Wool Textile Organisation, 2012). This study analysed 161 samples of commercial lots of Uruguayan wool (fineness ranging from 16 μm to 33 μm) to evaluate the equivalence between AF and LSN. A high statistical correlation was found, along with a lack of systematic and level-dependent bias when applying the IWTO-0 protocol (International Wool Textile Organization, 2020). This confirms that the Uruguayan wool matrix is compatible with both methods, allowing for their interchangeability within the limits of uncertainty. The evidence obtained supported a modification of the IWTO regulations. At the Lille Congress in 2025, an amendment was approved that exempts Uruguayan wool from the complementary AF measurement. This decision allows the country to certify MFD exclusively using LSN, which optimizes costs and aligns its standards with global markets, boosting the worldwide commercialization of wool.
Copyright (c) 2025 Karina Andrea Demaría Pérez, Santiago Nicolás Morales Yelpo, Pamela Stefani Ramos Olivera, Patricia Rafaela Zeballos Trinidad http://creativecommons.org/licenses/by-nc/4.0
Aplicación de ultrasonido en cultivos puros de Microcystis sp. y muestras de campo del Embalse San Roque (Córdoba, Argentina)
Water pollution is a global environmental issue. The reservoirs of Córdoba, Argentina, have been undergoing a continuous process of anthropogenic contamination for decades, leading to an advanced state of eutrophication. The San Roque Reservoir (ESR) experiences algal blooms, such as those dominated by Microcystis sp. These microorganisms can produce cyanotoxins and affect water use in various ways. An efficient mitigation method has not yet been implemented. Ultrasound represents a promising alternative. The aim of this study was to evaluate, through laboratory assays, the effect of ultrasound on the abundance and buoyancy of Microcystis cells, using samples extracted from the ESR and from a pure strain isolated from the same reservoir. Samples were exposed to ultrasound (f=124 kHz, P=20 W, t=20 min). Variables were analyzed through manual and automated cell counts. Intracellular chlorophyll was also measured by Aguas Cordobesas S.A., and the effects on gas vesicles were observed using transmission electron microscopy. Results showed a significant reduction in cell abundance in pure cultures and in the number of floating cells in ESR samples. These findings support the potential of ultrasound as a complementary tool in water quality management strategies.
Copyright (c) 2025 Araceli Ferreyra, Agostina Rigatuso, Camila Mussi, Pedro Mansur, Joaquín Fierro, Román Martino, Jonathan Muchiut, Rubén Vrech, Yadira Ansoar Rodriguez, Florencia Elisabeth Romero, Micaela Juaneda Allende, Guido Marconi, Andrés Rodríguez http://creativecommons.org/licenses/by-nc/4.0
Innovation in Hazardous Waste Treatment in Uruguay:
This study presents the experimental investigation of self-sustained smouldering (SSS) applied to the treatment of hydrocarbon-contaminated soils. A laboratory-scale smouldering reactor was employed. Four mixtures with different proportions of auxiliary fuel were evaluated, analysing the self-sustainability of the process, hydrocarbon removal, and the associated energy cost. The residue was characterised through elemental analysis, proximate analysis, thermogravimetry, and determination of the calorific value. The results demonstrated the need for an auxiliary fuel to initiate the SSS reaction. Spruce sawdust was selected for this purpose, and four mixtures containing sand and contaminated soil (M1, M2, M3, and M4) were prepared to assess their influence on process self-sustainability. The results indicate that mixture M4, containing 10 % sawdust and 90 % contaminated soil, is SSS and achieved a 95.23 % hydrocarbon removal. Additionally, the cost analysis estimated a value of 0.3224 USD/kg of treated residue, highlighting the economic viability of the technology and broadening the available options for final waste disposal. The implementation of smouldering combustion in Uruguay represents an efficient and accessible alternative for the management of hazardous waste, reducing dependence on conventional methods and promoting innovative solutions.
Copyright (c) 2025 Mirian Elizabeth Casco, Santiago Lassus Gerpe, Martín Torres Brunengo, Andrés Cuña Suárez http://creativecommons.org/licenses/by-nc/4.0
Botanical characterization of herbal drugs marketed in Uruguay
Herbal drugs are widely used for medicinal purposes, but their quality can be compromised by adulterations and deficiencies in control processes. In Uruguay, botanical analyses of these products remain scarce despite their growing demand. This study evaluated the botanical quality of 42 herbal drug samples used by local companies and laboratories prior to commercialization. The samples were analyzed through organoleptic characterization, macroscopic and microscopic examination, following the criteria established in Decree 289/018 of the Uruguayan Ministry of Public Health. It was determined that 69 % of the samples corresponded to materials of acceptable quality. The main causes of non-compliance were the presence of plant organs that are not part of the herbal drug, the presence of fungi, insects or inorganic material, and the use of incorrect species. In addition, cases of adulteration involving botanically related species were analyzed in detail, particularly in drugs from the families Apiaceae, Malvaceae and Asteraceae, selected for their recurrence in commercial samples evaluated in previous years. The results highlight the need to strengthen botanical quality controls in the marketing of herbal drugs in the country to ensure their authenticity, efficacy, and safety.
Copyright (c) 2025 Gastón Martínez Alfonso, Pilar Perna, Rossina Figliolo, Paula Rodríguez, Carmen Rossini http://creativecommons.org/licenses/by-nc/4.0
Fecal contamination on recreational beaches:
The increasing urbanization of the coastal strip and the lack of adequate wastewater treatment or sanitation have led to an increase in the load of fecal contaminants in the waters flowing into recreational beaches, putting the health of beachgoers at risk. Water quality monitoring assesses the abundance of microorganisms of intestinal origin, and the regulations establishing indicators, maximum allowable values (MPVs), and sampling methods vary among countries and regions. The objective of this paper is to provide input for the review of current regulations and recommendations for the management of this contamination in Uruguay. To this end, a bibliographic review of national (historic revision), regional (11 countries), and international (OMS, EPA) regulations regarding fecal contamination in recreational beaches (freshwater and marine) was conducted. Internationally, a variety of indicators are used to assess beach quality, with enterococci and Escherichia coli abundance being the most commonly used in the northern hemisphere, and fecal coliforms at regional and national level. Uruguayan regulations have not been updated for more than 45 years. They are the oldest regulations on the continent and one of the most permissive regarding fecal contamination. Therefore, we suggest updating Uruguay’s regulations, maintaining the current indicators, adding others such as E. coli and enterococci and decreasing their MPVs in order to preserve ecosystem health and protect the health of the population.
Copyright (c) 2025 Fernanda de León , Ángel Segura, Carla Kruk, Claudia Piccini http://creativecommons.org/licenses/by-nc/4.0
Optical properties, flow behavior and hardness of gels based on nanoemulsion
Due to the increase in the elderly population (>60 years), the food industry has as challenge to design foods for this population group, considering the swallowing changes that occur because of aging. Therefore, this work aimed to evaluate the effect of different hydrocolloid mixtures on the physical properties of gels based on nanoemulsions. Four samples were prepared using a base nanoemulsion (194 nm) with different mixtures of gelling agents: 5.25% APS-Soy Protein Isolate or APL-Whey Protein Isolate and 0.75% AG-Agar or CAR-k-carrageenan. The gels were characterized according to their optical, flow, and texture properties. The results showed that all gels had a yellow-beige color, especially those with APL. On the other hand, all the gels showed a slight drop in viscosity over time, which would facilitate their swallowing due to low fluidization. Furthermore, the hardness of the gels was <600 N/m2, which is considered adequate for the swallowing needs of older people. In conclusion, using hydrocolloid mixtures allows us to obtain gels based on nanoemulsions with flow and textural characteristics suitable for easy and safe swallowing, enabling the development of foods adapted to the sensory requirements of older people.
Copyright (c) 2024 Cristóbal Rojas-Pizarro, Matías Meneses Garrido, Karen Vielma Domínguez, Natalia Riquelme Hinojosa, Carla Arancibia Aguilar http://creativecommons.org/licenses/by-nc/4.0
Copyright (c) 2025 Centro de Información Técnica LATU http://creativecommons.org/licenses/by-nc/4.0
Instrumental texture and sensory characteristics of freeze-dried starfruit snacks with added trehalose and sucrose
This study assessed the impact of sucrose and trehalose as osmotic agents on the quality of freeze-dried starfruit snacks, with particular emphasis on sensory and textural attributes. Starfruit slices were subjected to three pre-treatments before freeze-drying: a control (no dehydration agent), osmotic dehydration in a sucrose solution (ODSAC), and osmotic dehydration in a trehalose solution (ODTRE). The resulting dehydrated samples were analyzed for water activity (aw), instrumental color and texture, and sensory attributes, including consumer acceptability. Both osmotic treatments significantly altered the instrumental texture of the starfruit slices compared to the control. Sensory analysis revealed significant differences in appearance, texture, flavor, and odor among treatments, with the ODTRE treatment receiving the highest acceptability scores. These findings suggest that using trehalose as an osmotic agent enhances the quality attributes of the dehydrated starfruit slices, supporting their potential as a fruit snack option.
Copyright (c) 2025 Mariela Guberman, Trinidad Sotera, Iván Méndez, Mara Virginia Galmarini http://creativecommons.org/licenses/by-nc/4.0
Inventory of cesium-137 and lead-210 in reference soils from the center-west of Uruguay:
This study characterizes inventory levels, concentration, and vertical distribution of 137Cs and 210Pbex in reference soils across Uruguay, establishing a baseline for future erosion and radiological monitoring studies. Seven sites were analyzed along a climatic gradient from south (Colonia) to north (Rivera). The 137Cs inventories were spatially homogeneous (357.8 – 365.4 Bq.m−2) and closely matched historical atmospheric deposition records from Buenos Aires, validating these as regional references. Conversely, 210Pbex inventories (3973 – 8428 Bq.m−2 in the upper 15 cm) strongly correlated with mean annual precipitation (R2 = 0.92, p = 0.01). Results indicate 137Cs inventories are stable and suitable as a general reference for erosion studies, whereas local-specific references are necessary for 210Pbex due to its environmental sensitivity. These findings provide a crucial baseline for assessing future radiological contamination from potential nuclear events in the region.
Copyright (c) 2025 Marcos Tassano, Pablo Cabral, Mirel Cabrera http://creativecommons.org/licenses/by-nc/4.0
Physicochemical properties of craft beer from barley malt and quinoa malt with dehydrated blackberry
This work aimed to develop a malt-barley and malta-quinoa craft beer with dehydrated fruit and evaluate the physicochemical properties. Ten treatments (barley-quinoa) of beer were carried out and analyzed; the different treatments were analyzed for color, anthocyanins, pH, total titratable acidity (ATT), volatile acidity, alcohol and density. In color, results were obtained for L* (luminosity) from 25.26 to 39.84, a* (red-green) from 1.85 to 7.11 and b* (blue-yellow) from 9.38 to 15.76. The anthocyanin content was 8.81 to 17.14 mg of cyanidin 3-glucoside/L. The pH was statistically the same (p ≤ 0.05) in all treatments. The alcohol content reached up to 7.13 % v/v. The craft beer is acceptable because adding quinoa malt and dehydrated blackberry did not affect the quality of anthocyanins, total titratable acidity, pH, alcohol content and volatile acidity of the craft beer.
Copyright (c) 2025 Ana Cristina de la Rosa Aguilar, Juan José Figueroa-González, Francisco Javier Cruz Guillén, Areli Leyva Maldonado, Martha Ávila Ontiveros http://creativecommons.org/licenses/by-nc/4.0
Validation of a methodology to estimate the biovolume of phytoplankton in a subtropical reservoir
This work presents the validation of a methodology for estimating the biovolume at the cellular and filamentous organization level of phytoplankton in the Salto Grande reservoir. The relevance of this study lies in its ability to generate reliable data in the field of ecology, supporting critical decisions in environmental management, while aligning with international and local regulations on water quality monitoring. An effort was made to integrate methodological quality assurance with ecological and health research, coinciding with criteria established by regulations such as the European Commission (2000) and the UNE 14996:2007 standard (Asociación Española de Normalización y Certificación, 2007), which contribute to the proper management of water resources. The main objective of this study was to accurately assess the ecological and health risks associated with bloom-forming organisms identified in the reservoir that impact the use of recreational areas. The results indicate that the validated analytical method presents a high degree of reproducibility and precision, both with values less than 10 %, essential characteristics for any technique aspiring to be used in environmental monitoring.
Copyright (c) 2025 Mariana Vidal, Facundo Bordet, Soledad Andrade http://creativecommons.org/licenses/by-nc/4.0
Copyright (c) 2024 Centro de Información Técnica LATU http://creativecommons.org/licenses/by-nc/4.0
Potential of very low enthalpy geothermal energy of Uruguay for closed vertical collectors
Currently it is a clear worldwide trend to strengthen the energy transition, favoring the use and diversification of renewable, low-carbon and environmentally friendly energies. Wind, solar and biomass energy are the most common, but there are other sources, such as the shallow geothermal energy. The latter takes advantage of the heat accumulated in the first meters of the subsoil for the heating and cooling of urban districts. This study presents the first map of shallow geothermal potential of Uruguay, for closed vertical collectors, based on the available geological and hydrogeological cartography and the German standard VDI 4640-2 (Verein Deutscher Ingenieure, 2019). The results indicate that Uruguay has a potential for medium to high heat extraction from rocks (greater than 40 W/m) in more than 60 % of its territory. This shallow geothermal energy potential could be used both for air-condition buildings and to provide thermal solutions to several of the activities carried out in the country (forestry, paper mills, cereal crops, dairy farming, among others) or promote the development of new productive activities, because it is a continuous, efficient and environmentally friendly energy.
Copyright (c) 2024 Martín Dos Santos Lafuente, Cintia Alcoba, Ethel Morales, Carlos Bello http://creativecommons.org/licenses/by-nc/4.0
Toxic cyanobacteria on the coast of San José, Río de la Plata, Uruguay
Dense blooms of potentially toxic cyanobacteria have been recorded on the north coast of the Río de la Plata estuary, which affect water quality for recreational or drinking water purposes. In this study we present results of a 7-years monitoring program in a coastal zone (Punta del Tigre, San José, Uruguay), with data of water temperature, conductivity, biomass and composition of cyanobacteria. The main objective was to determine the water temperature and salinity conditions associated with the dominance of cyanobacteria in the phytoplankton of the area studied. The concentration of total microcystins was quantified in selected samples. The blooms were also analyzed in satellite images based on the detection of chlorophyll a threshold. The most frequent species were potentially toxic: Microcystis aeruginosa, M. protocystis, M. novacekii, Dolichospermum circinale and D. uruguayense, often covering large areas in line with the satellite analysis. The concentrations of total microcystins generally exceeded the World Health Organization’s danger alerts for drinking water. Water temperatures above 19 °C, conductivities below 2 mS/cm and salinity below 0.5 were associated with a higher dominance of cyanobacteria in the total phytoplankton biomass. The high frequency of occurrence of these organisms in low conductivity conditions, common in the area, may compromise water quality for various uses, including human consumption.
Copyright (c) 2024 Sylvia Bonilla, Signe Haakonsson, María del Carmen Pérez, Fernanda Maciel, Francisco Pedocchi, Rafael Arocena http://creativecommons.org/licenses/by-nc/4.0
Analysis of the variability of conventional mass error in the calibration of 5 kg, 10 kg and 20 kg weights with 1 kg arrays
In this study, the standard deviations and error plots obtained from the measurement of five metrologists using different calibration arrays at nominal values of 5 kg, 10 kg and 20 kg of class F1 using 1 kg masses of class E2 were evaluated. Two arrays for 5 kg and three arrays for 10 kg and 20 kg were performed. Through compatibility index matrices, a reproducibility study was carried out for the different arrays with the respective nominal values. The results showed that, for the 5 kg weight, array 1 proved to be the most effective, showing a lower standard deviation compared to array 2, suggesting less variability among metrologists. For the 10 kg weight, array 3 presented the lowest standard deviation, standing out as the most reproducible option. For the 20 kg calibrations, arrangement 2 was identified as the most recommended, presenting a lower standard deviation compared to arrangements 1 and 3. These findings highlight the importance of choosing the most appropriate weight arrangement for this type of calibration in this scope. In this way, reproducibility can be ensured in this type of measurement, assuring the quality and reliability of the measurement method used.
Copyright (c) 2024 Katherine Quezada, Dimas Gracia, Abdiel López, José Díaz, Aníbal Candelaria, Edwin Aizpurua http://creativecommons.org/licenses/by-nc/4.0
This work seeks to formulate low-fat frozen pre-fried potato croquettes with a healthy nutritional profile, comparing their characteristics with market products. The filling and batter were formulated seeking to reduce the absorption of oil, using xanthan gum in the filling (0.15 %, 0.25 %, 0.35 %) and in the batter (0.15 %, 0.50 %, 0.85 %). The croquettes were prepared by pre-frying at 180 °C for 50 seconds, then frozen. The cooking of the croquette was finished by frying at 180 °C for 3 minutes. The formulated croquettes were analyzed and compared to 2 commercial products, based on fat content, instrumental texture, and instrumental color. It was observed that the fat reduction was significant, with values lower than those of the market. The sample with the lowest percentage of fat (1.8 %) contained 0.35 % filling and 0.50 % xanthan gum coating. On the other hand, the highest percentage of fat absorption (9.4 %) was obtained from the sample with a xanthan concentration of 0.15 % in the batter and 0.25 % in the filling. The maximum percentage of fat reduction was 81 %. Concerning instrumental texture and color, no significant differences were observed among the experimental croquettes. However, they did differ from the commercial products. Finally, the croquette with the lowest fat content was subjected to sensory comparison against the commercial croquettes. The selected formulation (0.35 % xanthan gum in the core - 0.50 % xanthan gum in the coating) showed similar acceptability to one of the commercial products and significantly higher acceptability compared to the other, indicating a potential market for this product. So, it was possible to significantly reduce the absorption of oil from fried croquettes by only modifying its formulation and thus obtain a product with a lower fat content than its market counterparts and with a higher acceptability by consumer.
Copyright (c) 2024 Patricia Lourdes Arcia Cabrera, Florencia García, Lara Pereira, Milagros Torrendell, Ana Curutchet http://creativecommons.org/licenses/by-nc/4.0
Quantitative analysis of the percentage of gas vesicles in Microcystis cells from the San Roque Reservoir (Córdoba, Argentina) treated with ultrasound
The genus Microcystis (Cyanobacteria) is of great interest due to its ability to form blooms in reservoirs and other bodies of water. Its cells possess gas vesicles that allow it to regulate its buoyancy. Numerous studies indicate that ultrasound, applied at certain frequencies and powers, causes the collapse of gas vesicles, although this effect has not yet been fully understood. The objective of this work was to quantitatively determine the effect that this technology exerts on gas vesicles and on the total abundance of Microcystis spp. extracted from the San Roque Reservoir, Argentina. To this end, 20 L of sample were exposed to 124 kHz and 20 W of ultrasonic treatment (T), and then cellular abundance and vesicle collapse were analyzed by quantifying their area and determining their relative percentage of the cells that settled using transmission electron microscopy. There were no variations in abundance, and a 10 % sedimentation occurred for T, where the percentage of vesicles in the cells showed a significant decrease. The numerical data on vesicle collapse adds relevance to this study; however, given the low percentage of sedimentation, it is important to continue investigating the effects of ultrasound on the loss of buoyancy in Microcystis spp. and its range of action.
Copyright (c) 2024 Florencia Elizabeth Romero, Araceli Ferreyra, Micaela Juaneda Allende, Mauro Gómez, Carlos Alberto Vitulich, Pedro Ruiz Díaz, Gastón Ojeda, Guido Marconi, María Valeria Amé, Camila Mussi, Victoria Baraibar, Pedro Mansur, Agostina Rigatuso, Joaquín Fierro, Román Martino, Lucía Boccardi, Silvana Raquel Halac, Diana Míguez, Andrés Rodriguez http://creativecommons.org/licenses/by-nc/4.0
Copyright (c) 2024 http://creativecommons.org/licenses/by-nc/4.0
Proliferation of submerged plants in Laguna Garzón:
Starting in summer 2023, Laguna Garzón registered excessive growth of submerged Myriophyllum quitense plants, covering the entire lagoon, which affected several uses of the system and generated social concern. This work describes the proliferation of aquatic plants, its effects on other biological communities, the environmental conditions that promoted it, and makes recommendations for its management. This species tolerates low to moderate salinities, and this is the first record of a proliferation of this magnitude in the lagoon. Plant cover increased water transparency and nutrients, reduced sediment phosphorus, and generated changes in the benthic community. The proliferation could be due to the high availability of nutrients compared to data from the 2000s and to the prolonged period with freshwater in the lagoon due to the lack of connection to the sea. It is suggested to make artificial openings of the sand bar with sufficient water levels to discharge water, sediments and plants, allowing the entry of marine water that affects plants and cyanobacteria due to their intolerance to high salinities. Mechanical harvesting can be a complementary measure in specific sites. These are measures based on the natural functioning of the system and of low cost.
Copyright (c) 2024 Lorena Rodríguez-Gallego, Carolina Lescano, Soledad Pasquariello, Elena Rodó, Andrea Cardoso, Sebastián Serra, Ana Martínez, Soledad Costa, Mariana Nin, Andrés Fernández http://creativecommons.org/licenses/by-nc/4.0
Interlaboratory comparison for electric energy in Panama and the Dominican Republic: a key exercise to maintain confidence and international recognition
This article describes the results of a comparison between two national metrology laboratories, located in Panama and the Dominican Republic, regarding electrical energy measurements carried out from August to October 2023. The intercomparison was developed with the objective of supporting calibration and measurement capabilities (CMC) of INDOCAL (Dominican Republic) in the magnitude of electrical energy, specifically for the calibration service of standards of this magnitude. To this purpose, the comparison of their measurement results was carried out against those issued by a laboratory with a recognized CMC and published in the database of the International Bureau of Weights and Measures (BIPM), in this case CENAMEP AIP (Panama). Because the participants consistently had an En < 1, it was not necessary to implement corrective actions in the participating laboratories to improve their electrical energy standard calibration processes. The results of this study strengthen the confidence of the technical management of the two participating laboratories and, consequently, of the national quality infrastructure in both countries.
Copyright (c) 2024 Julio González Vannucchi, Néstor Juan Rodríguez de la Cruz , Carlos Espinosa Bejarano, Juan Rafael Batista Donastorg , Jerry Irvam Mesa Nina , Jaime Estrella Engelmann , Saúl García Tovar http://creativecommons.org/licenses/by-nc/4.0
Effect of extreme low water levels 2020-2023 on the reproduction of migratory fish in the Uruguay River
The effect of extreme water level decreases on the reproduction of migratory fish in the Uruguay River was evaluated. Extreme water decreases have a negative effect on ichthyoplankton and provide new insights into the intensity of this effect during consecutive drought periods. The study compares the abundance and composition of ichthyoplankton during three consecutive reproductive periods (October-March) during extreme water level decreases in the river from 2020-2023, with data from the previous 10 years (2010-2020) through weekly samplings at four sites within the Salto Grande reservoir. Compared to the previous decade, decreases in the abundances of P. lineatus (60-85 %), Pseudoplatystoma spp. (52-79 %), L. patí (39-82 %), Pimelodus spp. (24-61 %), and Anostomidae (26-56 %) were observed, as well as temporal changes in ichthyoplankton density. Unlike the previous period (2010-2020), where harmful cyanobacteria blooms developed during summer droughts, during the extraordinary period caused by a hydrological phenomenon, no cyanobacteria bloom events were recorded. The absence of this harmful effect, combined with the resilience of fish observed during the previous period, generates reasonable expectations that at the end of the extraordinary period, fish will slowly recover their previous reproductive activity.
Copyright (c) 2024 Daniel Cataldo, Facundo Bordet, Lautaro Bruno http://creativecommons.org/licenses/by-nc/4.0
Effect of ethanol concentrations on the physicochemical, microbiological and sensory characteristics of an extract obtained from Vanilla planifolia
Vanilla is one of the most commercially important flavors used in the pharmaceutical, aromatherapy, perfumery, and food industries; however, the manufacturing processes of these products could involve operations that could affect the environment and the health of consumers. The objective of the present work was to evaluate the physicochemical, microbiological and sensory characteristics of hydroalcoholic extracts obtained from V. planifolia at concentrations T1:25, T2:35 and T3:45 % solvent. The results obtained showed that T3 had higher levels of pH (4.9), soluble solids 14.20 oBx, while T1 had a higher acidity (0.27) and density (0.97), the latter parameter not showing significant differences among treatments. The extracts obtained showed permissible levels of molds, yeasts, aerobic counts and absence of Salmonella spp, according to international standards, and finally, T3 had greater acceptability in sensory characteristics such as color, texture and general appearance, while T2 obtained greater acceptability with respect to aroma. Natural extracts obtained from V. planifolia represent an alternative that, in addition to improving the sensory qualities of foods, also contribute bioactive compounds.
Copyright (c) 2024 Carlos Julio Tubay Bermúdez, José Cedeño Velasco , Karol Yannela Revilla-Escobar, Karol Brigitte Moreira Jiménez, George García Mera, Luisa Ana Zambrano Mendoza http://creativecommons.org/licenses/by-nc/4.0
Assessing the efficiency of bamboo biochar in microcystin-LR removal from water
Developing sustainable and cost-effective adsorbents for removing microcystin-LR (MCLR) is crucial. Bambusa Tuldoides was pyrolyzed at various temperatures (400, 500, and 600 °C) and residence times (0.5 and 2 h) to produce a series of biochars. The observed MCLR adsorption capacity (219 μg g-1 for 600B0.5 sample) under pH conditions similar to those in a water treatment plant (pH = 7.6) is mainly attributed to hydrophobic interactions, π-π stacking, and the basic nature of the biochars (pHpzc > 8). A comprehensive analysis, including FTIR, elemental and proximate analysis, TG, SEM, N2 adsorption, Hg porosimetry and Raman spectroscopy support this finding. Additionally, to compare 600B0.5 with commercially available activated carbon, a dynamic study was conducted using actual contaminated water. 600B0.5 sample exhibits a removal efficiency of 99.5 %, resulting in a final concentration of 0.28 μg L-1, well below the World Health Organization guideline of 1 μg L-1.
Copyright (c) 2024 Yanaína Castro, Camila Hernández, Ana Claudia Pina, Diana Míguez, Mirian Elizabeth Casco http://creativecommons.org/licenses/by-nc/4.0
Laboratory test of predation of exotic amphibian larvae by native fish: basis for the biological control of the bullfrog in Uruguay
The decline of amphibians is a current concern, with the presence of invasive alien species (IAS) being one of the main threats to biodiversity. In Uruguay, one of the IAS that affects native biodiversity is the invasive exotic anuran Aquarana catesbeiana (bullfrog), invading more than 60 ponds in three locations. The present work proposes the analysis of the viability of biological control of bullfrog larvae, through the use of the native fish Rhamdia quelen (black catfish). A laboratory predation trial was carried out to evaluate whether it consumes the larvae of the exotic bullfrog and the native frog Leptodactylus luctator. Tadpoles in stages 24-26 (using Gosner’s criterion) of both species were exposed to direct predation and the number of larvae consumed by each R. quelen specimen was determined. Each fish preyed significantly on both species; however, the intensity was lower in exotic larvae (5 %) than in native larvae (70 %). The introduction of native fish species for biological control constitutes an opportunity in permanent water bodies where A. catesbeiana is well established. In an initial stage of the invasion process where there is the presence of other native species of amphibians, R. quelen would not serve for biocontrol, since it would eliminate the larvae of the native species, favouring the bullfrog.
Copyright (c) 2024 Marcelo Iturburu Di Fiore, Gustavo Saona, Ernesto Brugnoli, José Guerrero http://creativecommons.org/licenses/by-nc/4.0
Probiotic potential of Lactococcus lactis GU967439 isolated from raw milk: an in vitro study
Native probiotic strains are chosen for the production of functional dairy products due to their technological advantages. The preliminary selection of these strains is based on different in vitro tests that predict their safety and functional properties. This study aimed to evaluate in vitro antibiotic resistance, the effect of the passage through the gastrointestinal tract, and the antimicrobial activity of the native strain Lactococcus lactis GU967439 isolated from raw milk from a farm in Nueva Helvecia, Colonia, Uruguay. Lactococcus lactis ATCC N° 11454, was used as reference. L. lactis GU967439 was susceptible to antibiotics against Gram positives. In addition, it was resistant to the simulation of gastric juice at pH 3, pancreatin and bile. The cell-free supernatant of L. lactis GU967439 presented in vitro activity against Staphylococcus aureus ATCC 6538, Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Listeria innocua ATCC 33090, Streptococcus bovis 2.5 (WT) and had better activity than L. lactis ATCC N° 11454. However, none of them inhibited Gram-negative indicators (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 9027). These results allow for future studies to continue characterizing the probiotic potential of L.lactis GU967439.
Copyright (c) 2024 Camila Moreira, Silvana Carro Techera http://creativecommons.org/licenses/by-nc/4.0
Copyright (c) 2023 http://creativecommons.org/licenses/by-nc/4.0
Preliminary monitoring of glyphosate and its main metabolite in surface waters of the Santa Lucía River basin and in drinking water
The Santa Lucía River basin (CRSL) is the main source of drinking water supply for the population of Uruguay, and there is a significant use of the herbicide glyphosate (GLY) within it. The aim of this study was to carry out a preliminary monitoring of GLY and its metabolite aminomethylphosphonic acid (AMPA) in surface waters (AS) of the (CRLS) as well as at raw water (AB) and in the drinking water (AP) of the Aguas Corrientes potable water treatment plant (PPAC). GLY and AMPA were analyzed in 121 samples taken from August to December of 2020, 33 of which were AB from the PPAC, 33 were AP, and 55 were AS from the CRSL. It was found that in AB and AP the results for GLY and AMPA could not be quantified, which complies with national recommendations and regulations respectively. GLY and AMPA were detected and quantified in AS in the Canelón Chico creek sub-basin, with values below 1 μg/L. Even though these values comply with national recommendations for natural waters, they exceed European Union regulations. Furthermore, this finding indicates that the Canelón Chico creek sub-basin is one of the worst quality tributaries of the CRSL.
Copyright (c) 2024 Paulo Frontera, Andrea Somma , Andrés Pérez Parada, Eduardo Manta http://creativecommons.org/licenses/by-nc/4.0