Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco

The Santiago-Guadalajara River, located in western Mexico, is one of the most polluted rivers in the country, with widespread fecal contamination that presents a potential risk to public health, food safety, and biodiversity. This study investigated the spatial and seasonal behavior of fecal indicator bacteria (FIB) in the Santiago-Guadalajara River Basin (SGRB) using the most probable number (MPN) microbiological quantification technique and measuring the tributary flow rates in the main stem of the river and tributaries. Twenty-five sampling sites were monitored from July 2021 to April 2022. The mean of the microbial counts (MPN/100 mL) at the basin was as follows: total coliforms 2.5 × 10⁷, fecal coliforms 2.2 × 10⁷, and E. coli 2.1 × 10⁷. These FIB values position the Santiago-Guadalajara River as one of the most polluted rivers globally since it significantly exceeds the regulatory limits at the monitored sites, indicating insufficient sanitation infrastructure throughout the basin. A high level of correlation was found between FIB concentrations and monitored stream tributary flows, which allowed modeling the behavior of the FIB with respect to the flow regime throughout the basin. Quantitative microbial risk assessment revealed specific stations with elevated infection risks from Escherichia coli exposure. This field-based study provides valuable insights into the relationship between the variables that influence FIB concentrations in a highly polluted river and the potential risk to the exposed population.

Key message Proposal for a new fourth PEBP gene group (SFT-like) in a genomic context different from 21 the other three. FT/TFL groups evolved from MFT, but then became sub-, neo-functionalized. Abstract The phosphatidylethanolamine-binding protein (PEBP) gene family plays crucial roles in plant development, principally involved in flowering time regulation and seed development. Traditionally, PEBP genes are classified into three clades: MOTHER OF FT AND TFL1 (MFT), FLOWERING LOCUS T (FT), and TERMINAL FLOWER 1 (TFL). We used phylogenomic and microsynteny network analyses to explore the PEBP family across 275 plant genomes from different lineages. The phylogenetic tree of the identified 3707 PEBP proteins allows us to visualize a fourth clade within the PEBP family. This new clade, named SFT (Sibling of FT/TFL), is closely related to the MFT clade but sister to the branch point of FT/TFL subfamilies, suggesting a long-standing evolutionary divergence. In addition, the SFT subfamily is in a different genomic context, whereas FT and TFL share a common origin with MFT. Motif analyzes show differences between this new clade and those already reported, suggesting functions other than flowering or seed development. The Ka/Ks analysis also suggests that SFT clade had fewer duplication events, so these genes could have an important function for the plant that had not yet been elucidated. These findings offer new insights into the evolutionary history and functional diversification of PEBP genes in plants. This study provides an update on the classification of the PEBP family. By understanding the syntenic relationships and evolutionary dynamics within the PEBP family, this research sets the stage for future functional studies on PEBP genes in plant biology, particularly the recently identified SFT clade. Graphical abstract

Galactomannans (GMs) are polysaccharides with diverse industrial applications due to their functional properties, such as their use in thickeners, stabilizers, and gelling agents. Their use originated in the food industry and has rapidly expanded to other industries due to their biocompatibility, biodegradability, non-toxicity, and low cost. Galactomannans can be extracted from different plant species, resulting in gums with diverse physicochemical properties. Furthermore, there are different methods for their extraction and purification, each with their own advantages and disadvantages. The structure of galactomannans determines their application in industry, so their characterization is also important. This article presents a comprehensive review of galactomannan sources, as well as their extraction, purification, and characterization methods. It also includes the main applications of these polysaccharides in various sectors.

(1) Background: Plastic contamination is on the rise, despite ongoing research focused on alternatives such as bioplastics. However, most bioplastics require specific conditions to biodegrade. A promising alternative involves using microorganisms isolated from landfill soils that have demonstrated the ability to degrade plastic materials. (2) Methods: Soil samples were collected, and bacteria were isolated, characterized, and molecularly identified. Their degradative capacity was evaluated using the zone of clearing method, while their qualitative and structural degradative activity was assessed in a liquid medium on poly(butylene succinate) (PBS) films prepared by the cast method. (3) Results: Three strains—Bacillus cereus CHU4R, Acinetobacter baumannii YUCAN, and Pseudomonas otitidis YUC44—were selected. These strains exhibited the ability to cause severe damage to the microscopic surface of the films, attack the ester bonds within the PBS structure, and degrade lower-weight PBS molecules during the process. (4) Conclusions: this study represents the first report of strains isolated in Yucatán with plastic degradation activity. The microorganisms demonstrated the capacity to degrade PBS films by causing surface and structural damage at the molecular level. These findings suggest that the strains could be applied as an alternative in plastic biodegradation.

The potential of airborne bacteria as a sustainable alternative for agriculture was evaluated. Bacteria were isolated from air samples and evaluated for their plant growth-promoting (PGPB) and antifungal properties as biocontrol of phytopathogens. Results showed that diverse bacterial species, including Exiguobacterium, Rhodococcus, Kocuria, and Staphylococcus genera, exhibited PGPB activities such as phosphorus solubilization, siderophore production, and auxin production. Kocuria strains showed high auxin production. Rhodococcus sp. was observed to significantly promote root growth and the formation of beneficial biofilms on bean roots. Additionally, this bacterium opened the xylem vessels, facilitating the absorption of nutrients and water. Kocuria sp. strains exhibited high antifungal activity against Fusarium oxysporum and Phytophthora cinnamomi due to volatile organic compounds (VOCs) produced by these strains. Volatile profile revealed compounds such as dimethyl disulfide, pyrazines, and benzaldehyde derivatives associated with fungal growth inhibition. This study demonstrates the potential of airborne bacteria as both biofertilizers (producers of indole-3-acetic acid IAA, potassium, and phosphorus solubilizers, siderophore producers, and ammonium producers) and biocontrol agents (against the phytopathogenic fungus Fusarium oxysporum and Phytophthora cinnamomi). Graphical Abstract

Tequila vinasse, a by-product of agave fermentation, is a wastewater characterized by its dark coloration and complex composition, including water, alcohols, sugars, phenolic compounds, and proteins, among other constituents. Its elevated chemical oxygen demand (COD) and acidic pH levels render it hazardous to soil, plants, and aquatic organisms, requiring the development of efficient treatment strategies or proper disposal methods. It is worth noting that vinasse contains bioactive compounds with biotechnological potential. In this study, tequila vinasse at different concentrations (100%, 70%, and 50%) was subjected to a 10-day bioremediation process using the ligninolytic fungus Trametes sanguineus. The treatment resulted in reductions in color (48–76%), phenolic content (60–68%), and COD (22–36%) across all conditions. The highest laccase activity was observed in the 50% vinasse concentration, reaching 1,779 U/L on the fifth day of incubation. Subsequently, the detoxified vinasse was assessed for its impact on seed germination and seedling development. After fungal removal, the supernatant was directly applied to tomato (Solanum lycopersicum) and lettuce (Lactuca sativa) seeds. Germination rates exceeded 60% in both plant species, whereas untreated vinasse completely inhibited germination. Furthermore, seedling growth assays demonstrated that the treated vinasse supported root elongation in tomato and lettuce, exhibiting growth patterns comparable to those observed in the control. The high tolerance of T. sanguineus to tequila vinasse underscores its potential as a sustainable bioremediation strategy for vinasse detoxification.

Mature citrus leaves are less susceptible to infections and exhibit a higher response to diseases than younger leaves. However, the recalcitrance of mature leaves to Agrobacterium-mediated genetic transformation has hampered functional genomics research. In this study, we developed an efficient methodology for Agrobacterium-mediated transient transformation of mature leaves of Mexican lime (Citrus aurantifolia). We evaluated the effect on transient gene overexpression in mature Mexican lime leaves of different Agrobacterium strains and densities, chemical compounds to induce T-DNA transfer, surfactant and phytohormone concentrations, and pretreatment with microwounding. These conditions were tested first on detached leaves and then in-planta. Mexican lime leaves were inoculated by infiltration using a needleless syringe with Agrobacterium carrying a binary vector with the RUBY reporter. This vector converts tyrosine to bright red betalain, which can be assayed quickly and inexpensively. Pre-treatment with microwounding, dithiothreitol (100 µM), and Silwet (0.02%) increased the transformation efficiency of 5-week-old Mexican lime leaves. This resulted in leaf areas with 3- and fivefold higher betalain accumulation in detached and attached leaves, respectively. Significantly increased transient gene overexpression was confirmed by qRT-PCR analysis. Here we optimize a method of Agrobacterium-mediated transient genetic transformation of mature leaves of Mexican lime, reporting for the first time the in situ transient expression in mature leaves, which may contribute to the use of genetic engineering in studies to functionally characterize genes in mature leaves of this important species.

Glioblastoma (GBM) is a highly aggressive and malignant brain tumor, characterized by hypoxia in its microenvironment, which drives its growth and resistance to treatments. Hypoxia-inducible factor 1 (HIF-1) plays a central role in GBM progression by regulating cellular adaptation to low oxygen availability, promoting processes such as angiogenesis and cell invasion. However, studying and modeling GBM under hypoxic conditions is complex, especially due to the limitations of animal models. In this study, we developed a glioma spheroid model using an alginate–gelatin hydrogel scaffold, which enabled the simulation of hypoxic conditions within the tumor. The scaffold-based model demonstrated high reproducibility, facilitating the analysis of HIF-1α expression, a key protein in the hypoxic response of GBM. Furthermore, cell viability, the microstructural features of the encapsulated spheroids, and the water absorption rate of the hydrogel were assessed. Our findings validate the three-dimensional (3D) glioblastoma spheroids model as a valuable platform for studying hypoxia in GBM and evaluating new therapies. This approach could offer a more accessible and specific alternative for studying the tumor microenvironment and therapeutic resistance in GBM.

Los fructooligosacáridos (FOS) son carbohidratos no digeribles compuestos principalmente por cadenas de fructosa. Entre los FOS más importantes se encuentra el levano. Este biopolímero puede ser sintetizado por algunas plantas y microorganismos como bacterias y levaduras. La producción de levano por vía microbiana y por vía enzimática ha mostrado ser estrategias prometedoras para mejorar la eficiencia y la producción a gran escala. El levano tiene alta demanda en industrias como la alimentaria, la farmacéutica y la cosmética debido a sus propiedades fisicoquímicas que permiten utilizarlo como emulsificante, antioxidante, espesante, estabilizador y como prebiótico.

Background/objectives: Amino acids (AAs) play a critical role in diseases such as cystic fibrosis where Pseudomonas aeruginosa PAO1 adapts its metabolism in response to host-derived nutrients. The adaptation influences virulence and complicates antibiotic treatment mainly for the antimicrobial resistance context. D- and L-AAs have been analyzed for their impact on quorum sensing (QS), a mechanism that regulates virulence factors. This research aimed to reconstruct the genome-scale metabolic model (GEM) of P. aeruginosa PAO1 to investigate the metabolic roles of D- and L-AAs in QS-related pathways. Methods: The updated GEM, iJD1249, was reconstructed by using protocols to integrate data from previous models and refined with well-standardized in silico media (LB, M9, and SCFM) to improve flux balance analysis accuracy. The model was used to explore the metabolic impact of D-Met, D-Ala, D-Glu, D-Ser, L-His, L-Glu, L-Arg, and L-Ornithine (L-Orn) at 5 and 50 mM in QS-related pathways, focusing on the effects on bacterial growth and carbon flux distributions. Results: Among the tested AAs, D-Met was the only one that did not enhance the growth rate of P. aeruginosa PAO1, while L-Arg and L-Orn increased fluxes in the L-methionine biosynthesis pathway, influencing the metH gene. These findings suggest a differential metabolic role for D-and L-AAs in QS-related pathways. Conclusions: Our results shed some light on the metabolic impact of AAs on QS-related pathways and their potential role in P. aeruginosa virulence. Future studies should assess D-Met as a potential adjuvant in antimicrobial strategies, optimizing the concentration in combination with antibiotics to maximize its therapeutic effectiveness.

The color of maize grain, ranging from pink to purple, is related to the presence of phenolic compounds whose efficient extraction is affected by the solvent used. This study aimed to determine the effect of solvents and maize grain color on the phenolic composition and biological activities of maize extracts. Six samples (two with brick red, BR, two with cherry red CR, and two with blue–purple BP) of maize grain were used. The solvents were acidic methanol (MTFA) and aqueous acetone (AWAC). The phenolic composition was evaluated by total soluble phenolics (TSPs), anthocyanins (TACs), flavonoids (FLAVs), and proanthocyanidins (PAs). Biological activities evaluated were antioxidant capacity (AC), antifungal activity (AFA) and antimutagenic (AM) activity. The type of solvent used exerted a higher effect than the maize grain color on the phenolic composition of biological activities. The TAC and FLAV variables were more influenced by solvent than TSPs and PAs, while AC was affected only when evaluated by the DPPH method. AWAC extracts showed AFA and had the highest AM, unlike MTFA extracts. These results highlight the importance of selecting an appropriate solvent to maximize the functional properties of maize grain extracts and reach a more objective evaluation of the potential of food on its biological activities.

Currently, there is a particular interest in the study and identification of bioactive metabolites that can be used as phytomarkers in the standardization of fruit products consumed as natural alternatives for the prevention of chronic degenerative diseases. In this investigation, the chemometric analyses of data obtained from the metabolic (1H‐NMR) and chromatographic (UPLC‐MS) profiles, together with the results from antioxidant activity evaluations, allowed the identification of gallic acid and a quinic acid derivative as phytomarkers responsible for the antioxidant activity detected in crude extract of the fruits of Byrsonima bucidifolia. While the antioxidant activity of the fruit extract of B. bucidifolia is comparable to that of the positive control, its high content of gallic acid could be of interest for the pharmaceutical, cosmetic and food industries.

Plant-based proteins are increasingly recognized for their environmental, ethical, and nutritional benefits. However, their digestibility varies due to factors such as molecular structure, amino acid composition, and processing methods. This review comprehensively analyzes methods used to assess plant protein digestibility, including in vivo, in vitro, and ex vivo approaches. While in vivo studies, particularly those using pigs, are considered the gold standard, in vitro and ex vivo models offer cost-effective and reproducible alternatives for simulating digestion. Additionally, antinutritional factors present in plant proteins can hinder digestibility, necessitating processing strategies such as fermentation, enzymatic hydrolysis, and high-pressure treatments to enhance protein bioavailability. Advances in evaluation techniques, including the Digestible Indispensable Amino Acid Score (DIAAS) and dynamic digestion models, offer more precise assessments of protein quality. By systematically comparing these methods, this review aims to guide food scientists and manufacturers in selecting appropriate evaluation strategies to improve the nutritional quality of plant-based protein products. Understanding the mechanisms influencing plant protein digestibility is essential for optimizing food formulations and supporting the broader adoption of sustainable protein sources in human diets.

Bacteriophage therapy is a promising approach for targeting antibiotic-resistant bacteria and modulating gut microbiota in metabolic diseases such as obesity. This study evaluated the impact of a two-phage cocktail on an ex vivo colonic simulation model of gut microbiota derived from obese individuals, both in its normalized state and after enrichment with Enterobacter cloacae, an obesity-related bacteria. Microbiological analyses confirmed that the phage cocktail remained active throughout the colonic regions over three digestion cycles and effectively reduced enterobacterial populations in the enriched microbiota. Metabarcoding of the 16S rRNA gene revealed that phage therapy did not significantly alter the abundance of dominant genera, but selectively reduced E. cloacae across all colonic regions. Alpha diversity was significantly affected only in the enriched microbiota, while beta diversity analysis indicated significant compositional shifts during therapy, with reduced dispersion in the final treatment stage. Short-chain fatty acid profiling demonstrated region- and group-specific metabolic responses, with increased lactic and butyric acid concentrations in the ascending colon of the enriched microbiota following phage treatment. This study provides the first ex vivo evidence that a two-phage cocktail can selectively eliminate E. cloacae while preserving overall microbiota structure and functionality. These findings establish a foundation for future in vivo studies exploring the role of phage therapy in reshaping gut microbial communities and metabolic profiles, highlighting its potential as a precision tool for managing gut dysbiosis in metabolic disorders.

The discovery and design of antiviral agents have gained unprecedented significance due to the emergence of global health threats. The use of synthetic chemistry has enabled the modification of existing molecules and the creation of entirely novel compounds. In our laboratory, we have enzymatically synthesized a novel bioconjugate, lithocholic acid oleate (LO), derived from lithocholic acid (LCA), a bile acid that has been proven by researchers to exhibit antiviral activity in vitro. The study presented herein describes the preparative synthesis, formulation, and evaluation of LO both in vitro and in vivo for its antiviral activity against human herpes simplex virus 1 (HSV-1) as a model of viral infection. Evaluation of cytotoxicity using A549 cells indicated that a combination of LO (400 μM) and LCA (30 μM) exhibited a favorable safety profile while effectively inhibiting HSV-1 infection comparable to acyclovir treatment. Furthermore, in the in vivo assay, animals treated with an oily formulation containing 7% LO; 0.50% LCA; and 3% oleic acid (OA), 48 h prior to virus exposure, showed results even superior to a 5% acyclovir commercial formulation in terms of scar formation and wound recovery. These promising results enable the development of new preventive products against HSV-1 and probably other viruses.

In the present work, chitosan-glycidyl methacrylate-xanthan ((CTS-g-GMA)-X) hydrogel was successfully synthesized by the chemical reaction of a co-polymer of chitosan-g-glycidyl methacrylate (CTS-g-GMA), under different stoichiometric molar ratios from 1 : 1 to 1 : 4, and xanthan (X). (CTS-g-GMA)-X was synthesized by two methods to obtain a hydrogel: an aqueous acid media followed by neutralization and a neutral aqueous media, with an extended reaction time. Human epidermal keratinocytes (HEK) and nerve cells (neuroblastoma × glioma hybrid cell NG108-15) were sown over the hydrogels, and their vitality was determined using a calcein stain. The viability for keratinocytes and nerve cells was quantified using a DNA (proliferation) assay at several intervals. Additionally, immunocytochemistry, detecting E-cadherin, fibronectin, and laminin proteins in HEK, was performed to discard possible diseases caused by (CTS-g-GMA)-X hydrogels. The (CTS-GMA) shows greater results compared with the positive control (glass) and the pure chitosan; all polymers show similar satisfactory behaviors between them.

Introduction Cancer remains the leading cause of death worldwide, with increasing incidence rates. Natural compounds have gained attention as potential therapeutic agents due to their bioactive properties. Anthocyanins, particularly delphinidin-3-sambubioside (Dp-3-sam) and cyanidin-3-sambubioside (Cn-3-sam), are flavonoids with antioxidant and potential antitumor properties. This study investigates the antitumor effects of anthocyanins extracted from Hibiscus sabdariffa L. (H. sabdariffa), administered intratumorally, and their potential as adjuvants to chemotherapy. Methods Anthocyanins were extracted from H. sabdariffa and characterized using high-performance liquid chromatography (HPLC). The total phenolic content was determined using the Folin–Ciocalteu method. Antioxidant activity was assessed through DPPH, ABTS, and FRAP assays. The antiproliferative effects of Dp-3-sam and Cn-3-sam were evaluated in vitro using MCA-205 fibrosarcoma and CT26 colon carcinoma cell lines. In vivo studies were conducted on mouse tumor models to assess tumor growth inhibition following intratumoral administration of anthocyanins alone or in combination with doxorubicin. The impact on angiogenesis, immune cell recruitment, and long-term immune memory was also analyzed. Results HPLC analysis confirmed the presence of Dp-3-sam and Cn-3-sam in the H. sabdariffa extract. The anthocyanins exhibited significant antioxidant activity in all assays. In vitro studies demonstrated dose-dependent inhibition of cancer cell proliferation. In vivo, intratumoral administration of anthocyanins led to a significant reduction in tumor growth. The combination of anthocyanins with doxorubicin further enhanced tumor suppression. Mechanistically, Dp-3-sam and Cn-3-sam reduced angiogenesis and promoted immune cell recruitment but did not elicit an effective antitumor immune response alone. However, co-administration with doxorubicin reversed this limitation, leading to increased immune activation and resistance to tumor rechallenge, suggesting the induction of long-term immune memory. Discussion These findings highlight the potential of H. sabdariffa-derived anthocyanins as adjuvants in cancer therapy. When administered intratumorally, they enhance chemotherapy efficacy and immunogenicity. However, further studies are needed to optimize dosing strategies, evaluate long-term safety, and assess clinical applicability.

This article summarizes the findings of two of our own contributions and presents additional measurements that make us reach a conjecture about the physiological and molecular mechanisms that confer agaves their extraordinary capacity to withstand drought conditions. In these studies, we used terahertz (THz) spectroscopy and imaging to investigate the water retention mechanisms of agaves as well as the hydration dynamics of agave fructans, which are a peculiar type of carbohydrate produced by these plants. THz imaging was applied to map water distribution across different tissue regions, revealing a highly hydrated region in the core of the leaves and a less hydrated layer in the outside. Additionally, THz spectroscopy was used to study the hydration behavior of agave fructans in aqueous solutions. The hydration number and absorption coefficient increased nonlinearly with decreasing solute concentrations, reflecting the formation of complex hydration layers around these carbohydrates with an outstandingly large number of water molecules ( ${\sim}320$ ), which is 2 to 4 times larger than that of other carbohydrates such as inulin or maltodextrin. The findings underscore the importance of fructans in stabilizing membranes and enhancing drought tolerance by managing water at both tissue and molecular levels. This study demonstrates the versatility of THz technologies in plant science, offering a comprehensive approach to understanding water retention and hydration dynamics, with potential applications in improving agricultural practices for water-scarce environments.