A quantitative approach to the experimental transmission success of echinostoma friedi (trematoda: echinostomatidae) in rats

Using a range of parameters, the ability of rats (Rattus norvegicus) to successfully transmit Echinostoma friedi to the next host was examined under experimental conditions. The concept of Experimental Transmission Success (TM), defined as the number of hosts that become successfully infected after exposure to a number of infective stages produced by a previous host per unit of inoculation at which this latter host was exposed, was introduced. Using data for the egg output and miracidium hatching and infectivity, the TM permits us to estimate the ability of a particular defintive host species to successfully transmit a parasite species. This concept may be also useful to compare the transmission fitness of a parasite in different definitive host species. Moreover, variations of the Experimental Transmission Success over the course of the infection were calculated by the use of the Weekly Experimental Transmission Success (TMW). Overall, considering the complete duration of the experiment, the TM of E. friedi using rats as definitive hosts was 0.68 infected snails/metacercaria. However, positive values of the TMW were only obtained from 2 to 4 wk post-infection, with a maximum during the third wk post-infection. When comparing the TM values of E. friedi in rats with those calculated in hamsters on the basis of previously published data, E. friedi appears to be more appropriate to move through this portion of its life cycle when using hamsters (Mesocricetus auratus) as the final host than rats.Toledo Navarro, Rafael, [email protected] ; Carpena Hernandez, Ines, [email protected] ; Espert Fernandez, Ana M., [email protected] ; Sotillo Gallego, Javier, [email protected] ; Esteban Sanchis, Jose Guillermo, [email protected]

Development of an antibody-based capture enzyme-linked immunosorbent assay for detecting echinostoma caproni (trematoda) in experimentally infected rats: kinetics of coproantigen excretion

The present study reports on the development of a coproantigen capture enzyme-linked immunosorbent assay (ELISA) for detecting Echinostoma caproni in experimentally infected rats. The capture ELISA was based on polyclonal rabbit antibodies that recognize excretory–secretory (ES) antigens. The detection limit of pure ES was 3 ng/ml in sample buffer and 60 ng/ml in fecal samples. The test was evaluated using a follow-up of 10 rats experimentally infected with 100 metacercariae of E. caproni, and the results were compared with those of other diagnostic methods such as parasitological examination and antibody titers determined by indirect ELISA. Coproantigens were detected in all the infected rats from the first day postinfection (DPI). The period of maximal coproantigen excretion was between 7 and 21 DPI. The values remained positive until 49–56 DPI, coinciding with the disappearance of the eggs in the stool samples of the infected rats. The kinetics of coproantigen detection were correlated with those of egg output. The present assay provides an alternative tool for the diagnosis of the echinostome infections. The proposed capture ELISA makes possible an earlier diagnosis than that provided by parasitological examination and indirect ELISA and also allows for the differentiation of past and current infections. Our results show that this assay can also be used to monitor the course of echinostome infections.Toledo Navarro, Rafael, [email protected] ; Espert Fernandez, Ana M., [email protected] ; Marcilla Diaz, Antonio, [email protected] ; Esteban Sanchis, Jose Guillermo, [email protected]

Development of chocolates with improved lipid profile by replacing cocoa butter with an oleogel

The reformulation of chocolates seeks to find innovative alternatives to cocoa butter (CB) that are more economical and adhere to nutritional recommendations to replace saturated fats with unsaturated ones. In this research, chocolates were elaborated by substituting CB with an oleogel (OG) formulated with hydroxypropyl methylcellulose (HPMC) as an entrapper of sunflower oil by using the foam-templated approach. Four different CB/OG blends were prepared and characterized as potential CB substitutes (100/0 control), at replacement levels of 30%, 50%, 70% and 100% (70/30, 50/50, 30/70 and 0/100 blends), and subsequently, CB/OG-based chocolates (CB/OG-Ch) were formulated (100/0-Ch, 70/30-Ch, 50/50-Ch, 30/70-Ch and 0/100-Ch). Both the CB/OG blends and the CB/OG-Ch counterparts were characterized by dynamic and stationary rheology, hardness, thermal parameters, microstructure, and oil-binding capacity; in addition, the lipid profile of the chocolates was analyzed, and a sensory analysis was performed. Increasing the OG proportion in the CB/OG blend weakens the rigidity and strength of the fat-crystal network conferred by the CB, and decreases both its viscoelasticity and thermal parameters, but the differences between all the different properties and parameters of the CB/OG-Ch samples diminished in presence of the other ingredients used in the chocolate formulation. Sensory analysis evidenced that it is possible to replace up to 70% of CB with the OG, although from a technological point of view a replacement level of 50% would seem more appropriate. As compared to 100/0-Ch, 50/50-Ch and 30/70-Ch involve saturated fat reductions of 55% and 37%, respectively.This research was funded by project RTI-2018-099738-B-C21 from the Spanish Ministry of Economy, Industry and Competitiveness, and Intramural project CSIC: 202070E177.Peer reviewe

Thermorheological characterization of healthier reduced-fat cocoa butter formulated by substitution with a Hydroxypropyl Methylcellulose (HPMC)-based oleogel

Cocoa butter (CB) is a main ingredient in pastry due to the unique functional properties of its fat, which is high in saturated fatty acids (SFAs). However, excessive consumption of SFAs is associated with the occurrence of several chronic diseases. This study researched the partial or total replacement of CB by an oleogel (OG) formulated with a healthier lipid profile, for mixed systems that would allow a partial substitution of CB in confectionery products. The “emulsion-templated approach” was used to develop a sunflower oil-HPMC-based OG. Different CB:OG ratios were formulated increasing the percentage replacement of CB by OG from 50 to 100%. Rheological and textural properties were determined and compared with a CB control at 20 and 10 °C. Oil-binding capacity was also analyzed. The systems showed a solid-like behavior, with higher elastic than viscous modulus, which increased with CB concentration. Compared with 20 °C, at 10 °C there was an increase in connectivity, viscoelasticity, and consistency of the systems, in response to a more complete CB crystallization. The replaced systems also presented a better lipid profile than CB. This evidence suggests that formulated CB:OG system at 50:50 ratio could become useful as a CB equivalent in chocolate products.This research was funded by project RTI-2018-099738-B-C21 from the Spanish Ministry of Economy, Industry and Competitiveness, and Intramural project CSIC: 202070E177.Peer reviewe

Use of the foam-templated approach for obtaining healthier reduced saturated fat chocolates

Resumen del póster presentado a la Annual European Rheology Conference (AERC), celebrada en Sevilla (España) del 26 al 28 de abril de 2022.Chocolate is primarily composed of cocoa butter (CB). The CB continuous phase provides a network structure determining its microstructure, texture, crystallization, and rheological properties, and conferring chocolate its characteristic flavor (Li & Liu, 2019). In turn, a specific range of triglycerides (TAGs) contributes to the unique CB physical properties (Bahari & Akoh, 2018), and its appealing sensory characteristics. Reformulation of chocolates seeks to find alternatives to CB that adhere to nutritional recommendations to replace saturated fats with unsaturated ones. In this research, chocolates were elaborated by substituting CB with an oleogel (OG) formulated with hydroxypropyl methylcellulose (HPMC) by using the foam-templated approach (Patel, Schatteman, Lesaffer, & Dewettinck, 2013). Four CB/OG blends were prepared as CB substitutes (0% control), at replacement levels of 30, 50, 70 and 100%, and CB/OG-based chocolates (CB/OG-Ch) were formulated with each blend (100/0-Ch, 70/30-Ch, 50/50-Ch, 30/70-Ch and 0/100-Ch). Chocolates were characterized by dynamic (frequency sweep tests at 20 °C) and stationary (flow behavior and thixotropy at 5 s-1 at 40 °C) rheology and texture (penetration tests); in addition, a sensory analysis was performed and the lipid profile of chocolates was analyzed. Viscoelastic moduli evidenced that 100/0-Ch, 70/30-Ch and 50/50-Ch samples had similar internal structures with storage modulus close to 107 Pa. Both 30/70-Ch and 0/100-Ch, with higher percentage of CB replacement with the OG, had significantly lower viscoelastic moduli and displayed the highest Casson yield stresses. Sensory analysis showed that it would be possible to replace up to 70% of CB with the OG without negatively affecting the overall acceptability of the chocolates. As compared with 100/0-Ch, 50/50-Ch, 30/70-Ch and 0/100-Ch involved 37, 55 and 79% saturated fat reductions respectively, which are associated with lower risk of chronic degenerative diseases.Peer reviewe

Linear and nonlinear viscoelasticity of edible o/w emulsions used as saturated fat replacers

A recent strategy for controlling saturated fat intake consists on the design of vegetable oil-based emulsions. The aim was to characterize the linear and nonlinear viscoelastic properties of o/w emulsions formulated with two types of cellulose: MX (methylcellulose, MC) and F4M (hydroxypropyl methylcellulose, HPMC). The emulsions were characterized by steady flow curves and frequency sweeps in SAOS (Small Amplitude Oscillatory Shear) regime. In order to evaluate linear and non-linear response, strain sweeps were performed from 0.01 to 1000% strain amplitude at different frequencies (0.1, 1 and 5 Hz). Fourier Transform rheology and orthogonal stress decomposition were applied and LAOS (Large Amplitude Oscillatory Shear) parameters (G’M, G’L, ηM’, ηL’, S and T) were analysed. The type of cellulose ether significantly affected both flow behaviour and internal structure of the samples. MX emulsion presented greater consistency at rest and higher gel strength in SAOS regime with a lower frequency dependence than F4M emulsion. However, both emulsions presented similar properties at large deformations, showing shear thinning and strain stiffening behaviour. Nonlinear viscoelastic analysis allows to improve the textural characterization of emulsions, providing complementary useful information for establishing the most suitable formulation in experimental conditions closer to real applications and processes.This work is supported by the Spanish Ministry of Science, Innovation and Universities (Funding number: PID2022-137587OB-C21). IATA-CSIC is a Centre of Excellence Severo Ochoa (CEX2021-001189-S funded by MCIN/AEI/10.13039/501100011033).With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX 2021-001189-S)Peer reviewe

Mejora del perfil lipídico de bombones mediante la incorporación de aceite de girasol alto oleico estructurado

Póster presentado a las XXVI Jornadas Internacionales de Nutrición Práctica y al XV Congreso Internacional de la Sociedad Española de Dietética y Ciencias de la Alimentación, Sociedad Española de Dietética y Ciencias de la Alimentación, celebradas online del 29 al 31 de marzo de 2022.Proyecto RTI2018-099738-BC21 y CSIC:202070E177Peer reviewe

Kinetics of antibodies and antigens in serum of mice experimentally infected with echinostoma caproni (trematoda: echinostomatidae)

The present study reports on the kinetics of antibodies and antigens in serum of mice experimentally infected with 75 metacercariae of Echinostoma caproni during the first 12 wk postinfection (wpi). Antibody titers in the serum of mice were determined by an indirect enzyme-linked immunosorbent assay (ELISA) using excretory/secretory (ES) antigens of E. caproni. The early detection of antibodies against ES antigens of E. caproni is feasible using indirect ELISA. Mice developed significant antibody responses at 2 wpi, and the values progressively increased until the end of the experiment. This may be related to the intestinal absorption of adult worm antigens that induces humoral responses. The presence of E. caproni circulating antigens was determined by a capture ELISA based on polyclonal rabbit antibodies against ES antigens of E. caproni. High levels of seroantigens in mice were detected by 1–2 wpi, probably because of the local inflammatory responses in mice induced by the adult worms. A drop in circulating antigen levels was observed at 9 wpi, which could reflect changes in the intestinal tissues over the course of the infection.Toledo Navarro, Rafael, [email protected] ; Espert Fernandez, Ana M., [email protected] ; Marcilla Diaz, Antonio, [email protected] ; Esteban Sanchis, Jose Guillermo, [email protected]

Efficient P(3HB) extraction from Burkholderia sacchari cells using non-chlorinated solvents

A technique using safer, non-chlorinated organic solvents for the extraction of poly-3-hydroxybutyrate (P(3HB)) from bacterial cells was developed, aiming to attain high recovery yields and purities. Some solvents were selected from the GlaxoSmithKline guide as sustainable industrial solvents and the solubility of P(3HB) calculated using predictive equations from literature. Based on the calculated solubility values, anisole, cyclohexanone and phenetole were tested as extraction solvents and the relevant process variables (extraction temperature, extraction time and mass of cells/solvent volume ratio) were addressed. Polymer recovery yields of 97% and 93% were obtained with anisole and cyclohexanone, respectively, at 120–130 °C using a cell/solvent ratio of 1.5% (w/v). Maximum polymer purities using these experimental conditions were 98% for both solvents. The recovery yield and the polymer purity attained with chloroform (reference solvent) were 96 and 98%, respectively. Higher cell/solvent ratios of 6.0% (w/v) showed slightly lower recovery yields and purities. The average molecular weight and the thermal properties of the polymers extracted with the alternative solvents were fully comparable to those of the polymers obtained by chloroform extraction, demonstrating that the applied conditions did not significantly alter the properties of the extracted P(3HB).European Commission´s FP