Buriti oil is a vegetable oil extracted from the pulp and seeds of buriti (Mauritia flexuosa L.), a palm commonly found in the Amazon region, and is used both in popular medicine and in the cosmetic and food industries. This work aimed to develop a faster and more accessible procedure to quantify the content of carotenoids, polyphenols, and total flavonoids in buriti oils, where predictive models emphasize figures of merit. The study was carried out with 50 buriti oil samples from the state of Pará, Brazil, which were sampled by combining attenuated total reflection (ATR) spectroscopy with mid-infrared Fourier transform (FT-MIR) together with partial least squares regression (PLSR). The confidence and validation matrix were obtained from ultraviolet–visible spectroscopy. The PLSR model regarding the total carotenoid content presented values ​​between 335.33 and 1557.05 μg/g was validated by the concentration demonstration coefficient (R²cal) equal to 0.9556, prediction demonstration coefficient (R²_pred) equal to 0.85642, bias = 5.68.10⁻¹³, performance deviation ratio value (RDP) of 2.0135, and range error rate (RER) equal to 4.3747. Concentrations of phenolic compounds were predicted between 96.2964 and 121.857 GAE/100 g, where the model presented R²_cal = 0.9762, R²_pred = 0.8198, bias = 3.38.10⁻¹⁰, RDP = 5.9028, and RER = 5.7578. The flavonoid prediction model contains concentrations between 86.844 and 133.852 mg EC/100 g that circulate R²_cal = 0.9445, R²_pred = 0.8536, bias = 6.98.10⁻⁸, RDP = 6.7085, and RER = 6.7085. Buriti oil showed high levels of b-carotene. Prediction models are overwhelming and can be used for screening and quality control of natural products.

Brazil nut oil is highly valued in the food, cosmetic, chemical, and pharmaceutical industries, as well as other sectors of the economy. This work aims to use the Fourier transform infrared (FTIR) technique associated with partial least squares regression (PLSR) and principal component analysis (PCA) to demonstrate that these methods can be used in a prior and rapid analysis in quality control. Natural oils were extracted and stored for chemical analysis. PCA presented two groups regarding the state of degradation, subdivided into super-degraded and partially degraded groups in 99.88% of the explained variance. The applied PLS reported an acidity index (AI) prediction model with root mean square error of calibration (RMSEC) = 1.8564, root mean square error of cross-validation (REMSECV) = 4.2641, root mean square error of prediction (RMSEP) = 2.1491, R²_cal (calibration correlation coefficient) equal to 0.9679, R²_val (validation correlation coefficient) equal to 0.8474, and R²_pred (prediction correlation coefficient) equal to 0, 8468. The peroxide index (PI) prediction model showed RMSEC = 0.0005, REMSECV = 0.0016, RMSEP = 0.00079, calibration R² equal to 0.9670, cross-validation R² equal to 0.7149, and R² of prediction equal to 0.9099. The physical–chemical analyses identified that five samples fit in the food sector and the others fit in other sectors of the economy. In this way, the preliminary monitoring of the state of degradation was reported, and the prediction models of the peroxide and acidity indexes in Brazil nut oil for quality control were determined.

This study evaluated the impact of different fermentation boxes on the nutritional and antioxidant composition of dried lowland cocoa beans (Theobroma cacao L.), a characteristic product of some producers in the Amazon region. The analysis included ash content, moisture content, pH, titratable acidity, proteins, lipids, flavonoids, antioxidant activities (DPPH, ABTS, and FRAP), and mineral composition. Four types of fermentation boxes were assessed: a projected hexagonal box (PHB), square box (SB), basket (HP), and local square box (LSB). Statistical analyses included ANOVA, Tukey’s test, and Fisher’s LSD test to compare mean differences, while Principal Component Analysis (PCA) identified key contributors, including potassium and magnesium. Spearman correlation analysis revealed significant relationships between soil and almond nutrient profiles. The HP bed exhibited superior phenolic concentration, antioxidant activity, centesimal composition, and potassium and magnesium content. Despite its shorter fermentation period, the LSB bed met quality standards, while the PHB and SB showed intermediate results. Mineral analysis confirmed no toxicological risks, suggesting the beans are safe and enriched with floodplain minerals. These findings emphasize the importance of fermentation methods in determining cocoa bean quality and provide a framework for optimizing processes to enhance their nutritional and functional properties.

The objective of this work was to evaluate the use of chemometric tools associated with mid-infrared waves (ATR-MIR-FTIR) to determine the acidity index (AI) of Mauritia flexuosa oil extracted from plants from different locations. Thirty oil samples were collected in five municipalities of the state of Pará, Brazil. The principal component analysis, combined with Hotelling’s T² multivariate control test, was used to identify anomalous samples from the spectra. The ATR-MIR-FTIR analysis showed that the oil contains mainly monounsaturated acids, including oleic acid, which is directly correlated with AI. The first two principal components explained 99.93% of the cumulative variance. The statistical methods identified patterns of similarities between the samples with a close AI and tested an outlier from the sample with the highest AI. The application of ATR-MIR-FTIR, associated with chemometric methods, is appropriate to evaluate the acidity of buriti palm oil samples.

Macrofungi are key decomposers of organic matter and play an active role in biogeochemical cycles, thereby contributing to carbon sequestration in forest ecosystems. Floodplain forests (várzeas) are characterized by the dynamics of rising and receding waters, which are rich in suspended material and influence species variation and adaptation. The knowledge about the distribution of macrofungi in várzea environments in the Brazilian Amazon is limited. This study aims to evaluate the diversity and composition of macrofungi on three várzea forest islands, while also examining differences in species richness and abundance between seasonal periods. A total of 88 macrofungal species that belong to the phylum Basidiomycota were identified. The findings revealed significant variations in species composition, yet no notable differences in species richness or abundance were observed between the seasonal periods. The environmental conditions and resources available to macrofungi appear to be consistent among the islands, which leads to a balanced diversity. However, additional research is essential to uncover the true distribution patterns of macrofungi in the várzeas of the Brazilian Amazon, an area under significant threat to its biodiversity.

O objetivo deste artigo é relatar as experiências vivenciadas durante as atividades de educação sanitária e ambiental, desenvolvidas na comunidade de Campompema, região insular do município de Abaetetuba, no estado do Pará, em virtude das instalações do sistema de abastecimento com água da chuva. Como método de intervenção, foram utilizadas técnicas de dinâmicas em grupo. Posteriormente, ocorreram os registros das ações de educação sanitária e ambiental, as quais nortearam, principalmente, os cuidados com o manejo sustentável da água para o consumo humano. É possível constatar que a intervenção realizada possibilitou um espaço de acolhimento e de troca de vivências sobre os cuidados com a água. Também se refletiu acerca do modo de vida dos moradores da comunidade de Campompema. Após a realização de devidas técnicas em educação sanitária e ambiental a partir de metodologias ativas foi percebida a necessidade da continuidade do trabalho junto as famílias que receberam os sistemas de captação e armazenamento de água de chuva. Desta maneira, são necessários mais encontros para obter as mudanças esperadas em detrimento ao manejo da tecnologia social, a fim de promover conscientização e sensibilização da gestão socioambiental dos usos múltiplos da água.