REVISTA DE LA ASOCIACION COLOMBIANA DE CIENCIAS BIOLOGICAS

Effects of rainbow trout (Oncorhynchus mykiss) introduction on the diversity of aquatic insects in andean streams

Adriana Marcela Forero-Céspedes, Francisco Antonio Villa-Navarro — Tue, 20 Jan 2026 00:00:00 +0000

Introduction. Freshwater fish have been widely introduced into aquatic ecosystems, resulting in diversity losses, ecological alterations, and socioeconomic impacts. Among these species, the rainbow trout (Oncorhynchus mykiss) has been introduced in multiple regions, including the Colombian Andes, where it is presumed to negatively affect aquatic insect communities. Objective. To evaluate the effect of rainbow trout introduction on the diversity of aquatic insects in Andean streams. Materials and methods. The study was conducted on the eastern flank of the Central Cordillera, in Tolima (Colombia), between 2000 and 2600 m above sea level, in the upper Magdalena River basin. Stratified random sampling was used, on land cover (forest and non-forest), selecting 13 streams during the low rainfall season. The streams were divided into four treatments based on cover (forest or pasture/crops) and the presence of Astroblepus micrescens, A. trifasciatus, and rainbow trout. Results. 9,095 individuals were recorded, distributed across the orders Diptera, Ephemeroptera, Plecoptera, and Trichoptera, 31 families, and 58 genera, with rock and leaf litter being the preferred substrates for these organisms. Diptera and Trichoptera recorded the highest number of genera in all the treatments evaluated. The abundance of insects recorded by treatment was T1 = 1585 individuals, T2 = 980 individuals, T3 = 2482 individuals, and T4 = 4048 individuals. No significant differences were found in the abundance of the orders, but there were significant differences in aquatic insect richness between treatments. Conclusions. This study shows how the introduction of rainbow trout influences aquatic insect diversity, providing information to inform management strategies for this introduced species.

SNPs polymorphisms associated with gastric mucosal receptors and their effect on the interaction with Helicobacter pylori adhesins in Colombian subjects

Daniela Lizcano M, Lizeth Mejía O, Andrés Castillo G., Alvaro Pazos M — Fri, 09 Jan 2026 00:00:00 +0000

Objective: By characterizing single nucleotide polymorphisms (SNPs) present in gastric mucosal receptor genes and evaluating their interaction with Helicobacter pylori (H. pylori) adhesins, it is possible to identify a valid strategy for blocking its colonization and preventing gastric cancer (GC) in Colombia. Materials and Methods: SNPs associated with three gastric mucosal receptors were characterized: MUC5AC, PTPN11, and CEACAM3. Sixty-three exomes from individuals without gastric lesions and 14 exomes from patients in Nariño at risk of GC and infected with H. pylori were included. The causal effect of the variants was analyzed using the annotation programs PolyPhen-2, SIFT, MutationTaster, CADD, and I-Mutant. Two hundred and thirty-five H. pylori sequences were included for analysis of the babA, cagA, and hopQ genes, and a molecular docking analysis was performed using HDOCK. Results: 6/26 deleterious SNPs were identified in individuals without gastric lesions. In individuals with gastric pathologies and infected with H. pylori, 2/5 deleterious SNPs were identified: 24/87 amino acid changes in BabA; 42/87 in CagA; and 21/87 in HopQ. Conclusions: Variants in the amino acid sequence of the virulence factors BabA, CagA, and HopQ favor interaction with gastric mucosal receptor proteins MUC5AC, PTPN11, and CEACAM3, respectively. The identified SNPs induce affinity changes at the structural and functional levels favoring H. pylori colonization; therefore, they can be considered as potential molecular markers for intervention in the prevention of gastric cancer in Colombia.

Estimation of greenhouse gas emissions at the University of the atlantic, Colombia

María Marcela Escobar Ramírez, Carmiña Lucía Vargas Zapata — Tue, 30 Dec 2025 00:00:00 +0000

Introduction: Greenhouse gas (GHG) emissions, which constitute the Carbon footprint and serve as a key indicator of environmental impact and climate change, have gained increasing relevance in recent years. Objective: To analyze the estimates of different sources of direct and indirect GHG emissions at the Universidad del Atlántico in order to assess the environmental impact associated with academic and administrative activities carried out during 2018 and to propose measures for environmental management. Materials and Methods: The methodology was based on ISO 14064-1:2006 and the Greenhouse Gas Protocol (GHG Protocol), considering Scope 1, Scope 2, and Scope 3 emissions. Results: Scope 1 emissions from direct sources, mainly refrigerant gases and natural gas consumption, were the highest, totaling 6,493.12 tons of CO₂ equivalent (76.31%). Scope 3 emissions from other indirect sources, including transportation, waste generation, and land use, accounted for 1,240.66 tons of CO₂ equivalent (14.58%). Scope 2 emissions, related to indirect emissions from electricity consumption, contributed 849 tons of CO₂ equivalent (9.97%). After accounting for CO₂ removal by campus vegetation, the total carbon footprint was estimated at 8,507.78 tons of CO₂ equivalent. The main contributors to emissions were refrigerant equipment use, transportation (land and air), and land use. Conclusion: These findings highlight the need to implement environmental management strategies aimed at reducing or mitigating GHG emissions to promote a healthy environment. Accordingly, several measures are proposed for inclusion in the Environmental Management System of the Universidad del Atlántico.

Bacterial consortium to degrade sulfur compounds and mitigate gases and odors in wastewater

Laura Natalia Gutierrez J., Fabiana Maria Lora-Suarez., Nelsy Loango Chamorro — Sun, 28 Dec 2025 00:00:00 +0000

Introduction. The presence of sulfur compounds in wastewater is an environmental problem due to their toxicity and the generation of unpleasant odors. Sulfur-metabolizing bacterial consortia represent an efficient alternative for their degradation. This study evaluated a bacterial consortium composed of Aeromonas spp. and Pantoea agglomerans, isolated from the La Marina WWTP (Armenia, Quindío), for the bioremediation of sulfur compounds in domestic wastewater. Objective. To isolate and characterize a bacterial consortium (Aeromonas spp. + P. agglomerans) and evaluate its ability to degrade sulfur compounds in wastewater. Materials and methods. A bacterial consortium was isolated and formed from samples from the La Marina WWTP. Na₂SO₄ tolerance tests and incubation tests in wastewater under real conditions were performed. The decrease in sulfur compounds was evaluated using FTIR and Raman spectroscopy, and pH and dissolved oxygen were also recorded before and after treatment as indirect measures of H₂S reduction. Results. The strains tolerated concentrations of up to 20 mg/L of Na₂SO₄ without significant inhibition. P. agglomerans showed a greater capacity to remove sulfur compounds than Aeromonas spp. In addition, no inhibition was observed in co-culture and synergy was present. FTIR and Raman analyses, together with an increase in pH from ~6.9 to ~8.3 and in dissolved oxygen from ~0.15 to ~0.83 mg/L (equivalent to a 4.86-fold increase), showed a decrease in sulfur compounds after treatment. Conclusions. The bacterial consortium demonstrated efficacy in the bioremediation of sulfur compounds and improved effluent quality, demonstrating its potential biotechnological application.

In vitro preservation of Cyrtopodium schargellii using the minimal growth technique

Wed, 24 Dec 2025 00:00:00 +0000

Introduction: Cyrtopodium schargellii, known in certain areas as ‘lluvia dorada’, is an orchid native to Central America, distributed in countries such as Venezuela and Colombia. It is possible to find this orchid in Colombia in the department of Córdoba and other surrounding areas. Objective: The objetive of this research was to establish a viable and effective protocol for the in vitro conservation of the orchid C. schargellii; Materials and methods: for this purpose, seedlings of this species previously germinated in vitro were used, and then explants were taken and sown in culture media supplemented with 100% MS salts and two osmoregulators (mannitol and sorbitol) in four treatments for each substance: T1 (0.5%), T2 (1%), T3 (1.5%) and T4 (2%). In addition, a control was prepared (T0, without osmoregulators and with 100% MS salts). Results: In the case of mannitol, shoot and root formation was observed, accompanied by chlorosis and death of some explants, while in the case of sorbitol, little shoot and root formation was observed, but all explants survive. Conclusion: In conclusion, the in vitro preservation protocol given by 0.5% sorbitol was the best treatment for the preservation of this orchid.