: The prevalence and characteristics of chronic Chagas disease (CCD) in the Amazon Region remain underexplored. This study aimed to describe the challenges encountered during a serological survey and follow-up of CCD, while also highlighting potential risk factors in the Amazon Region. The serological survey involved residents of periurban and rural areas of Manaus in the Brazilian Amazon. All participants were invited to complete a clinical, epidemiological, and demographic questionnaire and provide a blood sample for anti-Trypanosoma cruzi (T. cruzi) IgG tests. A total of 1,845 participants were included, of whom 43 were identified as having presumed CCD, based on having at least two positive serological tests. Only 35 underwent complementary tests, and five had cardiac alterations not consistent with CCD. The main risk factors associated with CCD were age ≥20 years, living in periurban areas, reporting the presence of the insect vector inside the household, entering the forest, consumption of bushmeat, and having undergone blood transfusion. In the Amazon, the population is exposed to the sylvatic T. cruzi life cycle and is unaware of the associated risk factors. The divergent serology results raise doubts about the reliability of the commercial serological tests used for CCD screening in the region. Surveillance for CCD is important in the Amazon.

Endophytic fungi are recognized for their capacity to produce bioactive metabolites, yet their metabolic output is strongly modulated by preservation strategies. This study evaluated the influence of three long-term preservation methods—PDA slants with mineral oil (PB), Castellani’s method (PC), and filter paper with mineral oil (PF)—on the production of phenolic compounds and antioxidant activity by the Amazonian endophytes Cophinforma mamane and Aspergillus niger. Post-reactivation morphological analyses revealed method-dependent changes in colony pigmentation, texture, and sporulation intensity. PB preservation induced the most vigorous growth and enhanced sporulation in A. niger. For extracellular metabolites (AcOEt extracts), PB yielded the highest total phenolic content in A. niger (258.24 mg GAE/g), whereas PF and PC favored C. mamane (154.48 and 153.33 mg GAE/g). For intracellular ethanolic extracts, PB was most effective for C. mamane, producing 206.19 mg GAE/g for total phenols and the highest antioxidant activities (EC₅₀ = 1.40 mg/mL and FRAP = 95.61 µmol TE/g). HPLC–DAD identified protocatechuic acid as the predominant compound, which was especially abundant in PC and PF-preserved A. niger (60.76 and 85.38 µg/mg, respectively). Multivariate correlations indicated syringic (r = 0.53) and p-coumaric (r = 0.63) acids as the main contributors to antioxidant potential. These findings demonstrate that preservation methods may positively or negatively modulate fungal biosynthetic capacity, underscoring the importance of species-specific preservation protocols for maintaining metabolic stability in culture collections.

The increasing demand for safer and environmentally sustainable products has intensified the search for natural alternatives to synthetic dyes. Filamentous fungi are promising sources of natural pigments due to their metabolic diversity and the feasibility of large-scale production. In this study, filamentous fungi isolated from Amazonian freshwater environments were evaluated for their potential to produce natural pigment-associated metabolites under different nutritional conditions. Forty-five fungal isolates were screened in solid media and subsequently cultivated in submerged fermentation using three media: potato dextrose broth supplemented with yeast extract (BD + YE); malt extract broth (ME); and yeast extract–sucrose broth supplemented with magnesium sulfate (YES). Among the 39 pigment-producing isolates, seven were selected for further investigation. Sucrose favored the highest absorbance values of pigment extracts, particularly for isolates identified as Talaromyces amestolkiae. In addition, the extract of T. amestolkiae TA10P5-3 exhibited the highest absorbance value (6.83 abs. units at 400 nm) when cultivated in YES medium, indicating stronger chromophore-associated spectral signals. This extract also showed antimicrobial activity against Pseudomonas aeruginosa (625 μg/mL), Staphylococcus epidermidis (312 μg/mL), and Candida tropicalis (625 μg/mL). Finally, the TA10P5-3 extract presented high total phenolic content (246.30 mg GAE/g) and antioxidant activity (EC₅₀ = 5470 μg/mL). These findings highlight Amazonian freshwater fungi as promising sources of natural pigments with potential industrial applications.

The Amazon region harbors one of the richest biodiversities on the planet, representing a vast reservoir of bioactive compounds with high therapeutic potential. Although several Amazonian bioactives have already been incorporated into biopolymeric matrices, the effects of their incorporation on the mechanical, barrier, and biological properties of these materials remain insufficiently systematized. This review addresses this knowledge gap by critically analyzing reported Amazonian bioactive–biopolymer systems, with emphasis on how bioactive incorporation influences matrix properties, release behavior, and biological performance, particularly in biomedical applications. Emphasis is placed on the role of polymer–bioactive interactions in modulating physicochemical, mechanical, and transport properties, as well as in controlling release kinetics and biological performance. Different incorporation strategies, such as encapsulation and matrix embedding, are critically discussed in terms of their impact on stability and functionality. Overall, the reported studies demonstrate that Amazonian bioactives can substantially modulate the physicochemical, mechanical, barrier, and biological performance of biopolymeric systems, depending on the bioactive, polymeric matrix, and incorporation strategy. However, challenges related to variability in raw materials, lack of standardization, and limited reproducibility remain key barriers to translation and large-scale application.