Porcine astrovirus (PAstV) has been poorly studied and has been associated mainly with gastroenteritis. Computational analysis has revealed the close relationship of PAstV with astroviruses of humans (HAstV) and cats (FAstV). In this study, 105 and 171 stool specimens were collected from piglets and children under 5 years of age, respectively, in different Colombian regions during a 1-year period. The stool samples were examined for astroviruses by ELISA and RT–PCR; 23.8% and 4% were found to be positive for PAstV and HAstV, respectively. Additional sequence analysis with partial sequences obtained from ORF2 identified at least 2 probable groups of PAstVs and possible recombination events between porcine and human astroviruses. This study provides preliminary evidence of the high presence of PAstVs in pigs and proposes the existence of multiple PAstV types that are evolutionarily closely related to HAstVs.

Achyrocline bogotensis has been traditionally used to treat infections of skin, respiratory, tract urinary and other infections, but not to treat viral gastrointestinal disease. In this study, this Colombian native medicinal plant was investigated by its in vitro anti-rotavirus and anti-astrovirus activity. Several extracts and fractions phytochemically obtained from A. bogotensis were evaluated initially for their cell toxicity on MA104 and Caco2 cells and then for their anti-rotavirus (RRV) and anti-astrovirus (Yuc8) activity following three strategies: pre-treatment of cells (blocking effect), direct viral activity (virucidal effect) and post-treatment of infected cells (reduction of viral yield post-infection). In addition qualitative chemical studies were developed for the active compounds. Non-toxic concentrations of a fraction obtained exhibited antiviral activity against both viruses characterized by a virucidal effect and by the reduction of the infectious particles produced post-infection. Steroids, sterols, terpenes, phenols, flavonoids and sesquiterpenlactones were identified qualitatively in the active fraction. A. bogotensis contains substances with in vitro antiviral activity against rotavirus and astrovirus. This study confirms their anti-microbial properties and describes by the first time its antiviral activity in vitro.

Claudia Camila Mejía-Cruz, Emilia Barreto-Durán, María Alejandra Pardo-Pérez, María Camila Jimenez, Julieth Rincón, Karen Vanegas, Jorge Luis Rodríguez, Luis Fernando Jaramillo-Garcia, Juan Carlos Ulloa, Rodolfo Martínez Díaz, Efrain Leal-García, Rafael Pérez-Núñez, Alfonso Barreto, Viviana M Rodríguez-Pardo. IJSC 1999;0:. https://doi.org/10.15283/ijsc18061

Postbiotics produced by probiotic bacteria are gaining attention as multifunctional, food-derived agents with potential applications in human and animal health. This study investigates the production and biological activity of protein-rich postbiotics from Bifidobacterium adolescentis, cultivated under controlled conditions in a 3-liter bioreactor as a laboratory-scale model for functional ingredient development. Culture parameters were improved, and one representative batch was selected for biological evaluation. The postbiotic preparation was tested for cytotoxicity using MA104 (renal) and C2BBe1 (intestinal) epithelial cell lines through viability and cell death assays, confirming its safety across a range of concentrations. To assess its functional activity, we evaluated its ability to reduce rotavirus infection and preserve epithelial integrity. The postbiotic significantly reduced viral infectivity and maintained cytoskeletal architecture in infected intestinal cells, supporting its potential protective role. These findings suggest that B. adolescentis-derived postbiotics may serve as safe and biologically active compounds with potential applications in intestinal health and viral infection management.

We are reporting computational studies of several genotyped strains of astrovirus isolated in Colombia which we have genotyped using the 348-bp segment located between nucleotides 258 and 606 close to the amino terminal region of the complete ORF 2. By biocomputational techniques this 348-bp segment from the different strains was translated into an amino acid sequence. The sequences were aligned and compared in order to build a dendrogram. Our results show that the 348 bp and the 116 amino acid peptides cluster in a very conservative way, showing slight genetic variations between them. This slight sequence variability does not allow us to identify common amino acid substitution patterns shared by all members of each HAstV specific type, thus suggesting that antigenic epitopes are probably located outside the 116 peptide fragment of this capsid protein. These results show that there is little recombination among different regions of the ORF2, thus suggesting that this genotyping method should continue to be useful for serotyping HAstV isolates.

Acute diarrheal disease (ADD) caused by rotavirus (RV) contributes significantly to morbidity and mortality in children under five years of age. Currently, there are no specific drugs for the treatment of RV infections. Previously, we reported the anti-rotaviral activity of the protein metabolites derived from Bifidobacterium adolescentis. In this study, our aim was to assess the impact of B. adolescentis-secreted proteins (BaSP), with anti-rotaviral activity on the human intestinal C2BBe1 cell line. We initiated the production of BaSP and subsequently confirmed its anti-rotaviral activity by counting the infectious foci using immunocytochemistry. We then exposed the C2BBe1 cells to various concentrations of BaSP (≤250 µg/mL) for 72 h. Cell viability was assessed using the MTT assay, cell monolayer integrity was monitored through transepithelial electrical resistance (TEER), and cytoskeleton architecture and tight junctions (TJs) were examined using confocal microscopy with F-actin and occludin staining. Finally, we utilized a commercial kit to detect markers of apoptosis and necrosis after 24 h of treatment. The results demonstrated that BaSP does not have adverse effects on C2BBe1 cells. These findings confirm that BaSP inhibits rotavirus infectivity and has the potential to strengthen intestinal defense against viral and bacterial infections via the paracellular route.