Federal University of Paraíba

Despite the growing interest in cactus-derived edible coatings and lactic acid bacteria (LAB)-based biocontrol systems, information on the use of cactus mucilage as a functional matrix for LAB cultures for the control of postharvest fungal diseases remains limited. Thus, this study evaluated the efficacy of coatings formulated with the mucilage of Pilosocereus pachycladus (facheiro) and Nopalea cochenillifera (palm) and incorporated with a mixed LAB culture for the control of anthracnose caused by Colletotrichum siamense in ‘Margarida’ avocado. The mucilages exhibited suitable physicochemical and technological properties for application in coating formulations. In vitro assays showed that cactus mucilage (2–4% w/v) exhibited dose-dependent inhibition of C. siamense, with the highest values observed at 3–4% (w/v), depending on the mucilage matrix, reaching up to 82.0% inhibition. LAB strains also showed strong antifungal activity, with mycelial growth inhibition ranging from 34% to 100%. The three most effective and compatible LAB strains (Lactiplantibacillus plantarum 49, Lactiplantibacillus pentosus 129, and Limosilactobacillus fermentum 263) were combined in equal proportions (1:1:1, v/v) to prepare a mixed culture standardized to 9–10 log CFU mL⁻¹ . The interaction between mucilage and the mixed LAB culture was additive (Abbott index, AI = 0.6–1.1), indicating enhanced antifungal effects. The mixed LAB culture maintained high viable cell counts (>7 log CFU mL-¹) for 15 d at 25 °C in the coating matrix. In situ assays demonstrated that the coatings significantly reduced anthracnose lesion development (32–100%) on avocados artificially inoculated with C. siamense, with the highest efficacy and greatest stability observed for the palm mucilage + LAB formulation. The coatings also reduced weight loss during storage without negatively affecting other fruit quality attributes. Cactus mucilage coatings, particularly when combined with mixed LAB cultures, show potential for the biological control of postharvest anthracnose in avocado.

We address the stochastic transmission expansion planning (STEP) problem under uncertainty in renewable generation capacity and demand. STEP’s objective is to minimize total transmission investment and generation costs. To tackle the computational challenges posed by large-scale systems, we propose a heuristic strategy that combines the progressive hedging (PH) algorithm for scenario-wise decomposition with an integrated approach for solving the resulting subproblems. The latter combines a destroy-and-repair operator, a beam search procedure, and a mixed-integer programming solver. The proposed framework is evaluated on large-scale systems from the literature with up to 10,000 nodes, adapted to stochastic scenarios using parameters from the California test system (CATS). Compared with a non-trivial baseline algorithm that includes the same integrated approach, the proposed PH-based method consistently improved solution quality for the six systems considered (including CATS), achieving an average cost improvement of 5.28% within a 2-hour time limit.

Multiform glioblastoma (GBM) is the most aggressive primary brain tumor, associated with high heterogeneity, treatment resistance, and poor survival. Temozolomide (TMZ), although the main chemotherapeutic agent used, shows limited efficacy due to low solubility, chemical instability, and acquired resistance. In this context, nanostructured systems can enhance their antitumor efficacy. This study aimed to develop and characterize chitosan-functionalized nanostructured lipid carriers loaded with Temozolomide (NLCTQ), as well as to assess their biological activity in human glioblastoma cells (U87-MG). Lipid nanoparticles functionalized with chitosan were prepared by hot emulsification and sonication. Physicochemical characterization included DLS, zeta potential, FTIR, and HPLC for drug quantification and encapsulation efficiency. Biological activity was evaluated in U87-MG cells using the cell viability assay MTT and trypan blue, the comet assay, the spheroid model, fluorescence cell death, and the CBMN assay. The formulation presented a homogeneous nanometric size and positive zeta potential, although with moderate encapsulation efficiency (39%). Biological assays demonstrated that NLCTQ significantly reduced cell viability, overcoming the U87-MG cell line's resistance to TMZ by achieving cytotoxicity at doses up to 20 times lower than free TMZ. Additionally, NLCTQ promoted the formation of biomarkers of chromosomal instability, such as micronuclei, bridges, and nuclear buds, which may explain the observed cytotoxic effects. Together, the results indicate that TMZ nanoencapsulation in NLCTQ enhances its antitumor efficacy, representing a promising strategy to overcome the limitations of conventional chemotherapy in glioblastoma treatment.

The Brazilian semi-arid region is composed of a landscape mosaic that reflects a complex and diversified soil cover. In this context, research that integrates geology and geomorphology can efficiently guide pedological investigations in heterogeneous environments. This research was aimed at evaluating the soil-landscape relationships and their correlation with soil attributes in a toposequence over granites in the semi-arid region (Caatinga) of Northeastern Brazil. A transect was delimited in the landscape, and in each slope segment, a soil profile was described and sampled, namely: a) summit (P1); b) shoulder (P2); (c) backslope (P3), and; footslope (P4). Physical and chemical attributes were evaluated. Mineralogical analyses of sand, silt, and clay fractions were conducted by X-ray diffraction, and the total contents of major elements were determined by X-ray fluorescence. An E horizon in the upper third confirms that argilluviation is an active process in this landscape segment. Elutriation and argillization (in situ clay formation) also form the textural gradient, including in the foothill segment, producing Lixisols with strong rubification in the Bt horizon. Expansive clays (e.g., montmorillonite) contribute to vertisolization and the higher exchangeable and total calcium and magnesium contents in the top and foothill segments (Vertisols). At the summit, the melanization of the Bw diagnostic horizon is also evident. The variation in morphological, physical, chemical, and mineralogical attributes under similar parent materials confirms the role of relief in the distribution of materials along the toposequence and in the genesis of soils.

Abstract Monocropping systems of Zea mays L. in Brazilian biomes exert strong pressures on the functionality of Cambisols. This study aimed to assess the influence of organic fertilization on the chemical properties of Cambisols across four Brazilian biomes (Amazon, Atlantic Forest, Caatinga, and Cerrado), as well as on plant nutrient extraction patterns, the microbial community within the rhizosphere of Z. mays, and crop yield. Under greenhouse conditions over three cultivation cycles, soil pH, soil organic carbon (SOC), available P, total N, plant dry biomass, yield, macro- and micronutrient extraction, microbial gene abundance, and dsDNA content were evaluated in Cambisols from different Brazilian biomes under two treatments (organic fertilization × control). Higher values of SOC, available P, total N, shoot and root dry biomass, yield, extraction of N, P, Mg, S, B, Cu, Fe, and Zn, as well as bacterial and fungal gene abundance and dsDNA content, were observed in soils receiving organic fertilization. The findings suggest that organic fertilization enhances plant performance, soil fertility, nutrient dynamics, and rhizosphere functioning in Cambisols, contributing to improved maize yield. Organic inputs were associated with (i) increases in SOC, available P, and total N; (ii) greater abundance of bacterial and fungal genes and higher dsDNA content; (iii) enhanced extraction of macro- and micronutrients; and (iv) the potential to support the conservation of Cambisols while contributing to food security and sustainable agricultural practices.