Harnessing Small-Molecule Analyte Detection in Complex Media: Combining Molecularly Imprinted Polymers, Electrolytic Transistors, and Machine Learning.

Small-molecule analyte detection is key for improving quality of life, particularly in health monitoring through the early detection of diseases. However, detecting specific markers in complex multicomponent media using devices compatible with point-of-care (PoC) technologies is still a major challenge. Here, we introduce a novel approach that combines molecularly imprinted polymers (MIPs), electrolyte-gated transistors (EGTs) based on 2D materials, and machine learning (ML) to detect hippuric acid (HA) in artificial urine, being a critical marker for toluene intoxication, parasitic infections, and kidney and bowel inflammation. Reduced graphene oxide (rGO) was used as the sensory material and molecularly imprinted polymer (MIP) as supramolecular receptors. Employing supervised ML techniques based on symbolic regression and compressive sensing enabled us to comprehensively analyze the EGT transfer curves, eliminating the need for arbitrary signal selection and allowing a multivariate analysis during HA detection. The resulting device displayed simultaneously low operating voltages (<0.5 V), rapid response times (≤10 s), operation across a wide range of HA concentrations (from 0.05 to 200 nmol L-1), and a low limit of detection (LoD) of 39 pmol L-1. Thanks to the ML multivariate analysis, we achieved a 2.5-fold increase in the device sensitivity (1.007 µA/nmol L-1) with respect to the human data analysis (0.388 µA/nmol L-1). Our method represents a major advance in PoC technologies, by enabling the accurate determination of small-molecule markers in complex media via the combination of ML analysis, supramolecular analyte recognition, and electrolytic transistors.

Association between Polyphenol Intake and Lipid Profile of Adults and Elders in a Northeastern Brazilian Capital.

This research was aimed at evaluating the relationship between the estimated polyphenol intake and the atherogenic lipid profile in adult and elder residents in the city of Teresina, located in the Northeastern Region of Brazil. This study was a cross-sectional population-based survey with 501 adults and elders, conducted in Teresina, Brazil. Food intake was obtained by 24-h food recall. The estimated polyphenol intake was calculated by multiplying the food consumption data from the recall by the polyphenol content in the foods described in the Phenol-Explorer database. The mean intake of total polyphenols was 1006.53 mg/day. The phenolic acids was the class with the highest intake, followed by the flavonols. Coffee, beans and apples were the main foods contributing to the total polyphenol intake. In the individuals with elevated serum concentrations of total cholesterol and triglycerides, the intake of total polyphenols was significantly higher. The intake of total polyphenols, phenolic acids and lignans was higher in the subjects with dyslipidemia. This article provides, for the first time, data on the intake of the total polyphenol classes and subclasses in the evaluated population and the relationship with the lipid profile. The individuals with a higher intake of total polyphenols had a worse lipid profile, which may be a consequence of an improved diet in those individuals who present with dyslipidemia.

Vitamin C and Phenolic Antioxidants of Jua (Ziziphus joazeiro M.) Pulp: A Rich Underexplored Brazilian Source of Ellagic Acid Recovered by Aqueous Ultrasound-Assisted Extraction.

Jua (juá in Portuguese) is an underexplored fruit from Brazil's northeast. This fruit is rich in antioxidant substances. However, there is a dearth of information about jua's bioactive potential. The present study evaluated two extraction methods (continuous agitation and ultrasound-assisted extraction-UAE) and employed three different solvents (water, ethanol, and acetone) to efficiently recover soluble phenolic compounds. Aqueous extracts obtained by UAE showed the highest total phenolic content (TPC) and antiradical activity. Besides being an eco-friendly procedure, extraction and/or solubility in an aqueous medium is also important for food application. Ellagic acids were the predominant phenolics (80%) found in aqueous jua pulp extract obtained by UAE, as determined by HPLC, while its TPC was 405.8 gallic acid equivalent per gram of fruit. This extract also exhibited a higher scavenging activity towards peroxyl radicals when compared to that of several other fruits from the literature, including grape, strawberry, cranberry, and walnuts, which are known references in terms of antioxidants. This is the first report that demonstrates jua pulp's potential as an alternative source of ellagic acid and other phenolic acids and flavonoids. Therefore, the outcome of this study provides new information that can be useful for functional food and nutraceutical industries.

IN VITRO AND IN VIVO ANTIOXIDANT ACTIVITY OF BURITI FRUIT (MAURITIA FLEXUOSA L.F.).

INTRODUCTION: studies have shown high concentration of monounsaturated fatty acids, carotenoids, polyphenols and ascorbic acid in Buriti fruit (Mauritia flexuosa L.f.). This study evaluated the in vitro and in vivo antioxidant activities of buriti fruit (Mauritia flexuosa L.f.). METHODS: the chemical composition and total phenolic and carotenoid contents of the buriti pulp and the feed rations were determined, and the in vitro antioxidant activity was analyzed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay. Wistar rats (21 days old) were randomly allocated (n=10) into a control groups and experimental groups (feed enriched with buriti pulp). After 60 days, the in vivo antioxidant activity was evaluated through the determination of the catalase activity and non-protein sulfhydryl (NPSH) groups in the liver and quantification of malondialdehyde (MDA) in the plasma and tissues. RESULTS: high contents of oleic fatty acids (73.3%), phenolic compounds (192 ± 0.3 mg/100 g) and carotenoids (23.9 ± 0.5 mg/100 g) as well as elevated in vitro antioxidant activity were found in the buriti pulp. The enriched diet had higher contents of phenols and carotenoids as well as higher antioxidant activity compared with the standard feed (p < 0.05). There were no differences between the groups regarding catalase activity in the liver and MDA concentrations in the plasma, liver and kidneys. The male rats of the experimental group had higher liver concentrations of NPSH compounds (p < 0.05). CONCLUSION: these results may corroborate the claim that buriti fruit is an antioxidant functional food and support its utilization in a nutritionally balanced diet.

Introducción: estudios previos han demostrado que la fruta Burití (Mauritia flexuosa L.f). posee una alta concentración de ácidos grasos monoinsaturados, carotenoides, polifenoles y ácido ascórbico. Este estudio evaluó la actividad antioxidante in vitro e in vivo del Burití. Métodos: fueron determinadas la composición química, el contenido de compuestos fenólicos y de carotenoides tanto de la pulpa del Burití como de las raciones de alimento. La actividad antioxidante in vitro fue analizada utilizando el ensayo del radical 2,2-difenil-1-picrilhidrazil (DPPH). Ratas Wistar (21 días de edad) fueron asignadas al azar (n = 10) en grupos controles y grupos experimentales (alimentación enriquecida con pulpa de Burití). Después de 60 días, la actividad antioxidante in vivo se evaluó mediante la actividad enzimática de la catalasa y grupos sulfhidrílo no proteico (NPSH) en el hígado, y se cuantificó el malondialdehído (MDA) en plasma y tejidos. Resultados: la pulpa del Burití presentó alto contenido de ácido graso oleico (73,3%), compuestos fenólicos (192 ± 0,3 mg/100 g) y carotenoides (23,9 ± 0,5 mg/100 g), así como una elevada actividad antioxidante in vitro. La dieta enriquecida tenía mayor contenido de fenoles y carotenoides, y una mayor actividad antioxidante en comparación con la alimentación estándar (p < 0,05). No se observaron diferencias entre los grupos con respecto a la actividad de la catalasa en el hígado y las concentraciones de MDA en plasma, hígado y riñones. Las ratas macho del grupo experimental tuvieron concentraciones hepáticas más altas de NPSH (p < 0,05). Conclusión: estos resultados pueden corroborar la hipótesis de que la fruta Burití es un alimento funcional antioxidante y su consumo es conveniente en una dieta nutricionalmente equilibrada.

Identification of Phenolic Compounds and Evaluation of Antioxidant and Antimicrobial Properties of Euphorbia Tirucalli L.

Bioactive compounds extracted from natural sources can benefit human health. The aim of this work was to determine total phenolic content and antioxidant activity in extracts of Euphorbia tirucalli L. followed by identification and quantification of the phenolic compounds, as well as their antibacterial activities. Antioxidant activities were determined by DPPH and ABTS(•+) assay. Identification of phenolic compounds was performed using high-performance liquid chromatography (HPLC), and antimicrobial activities were verified by agar dilution methods and MIC values. Total phenolic content ranged from 7.73 to 30.54 mg/100 g gallic acid equivalent. Extracts from dry plants showed higher antioxidant activities than those from fresh ones. The DPPH EC50 values were approximately 12.15 µg/mL and 16.59 µg/mL, respectively. Antioxidant activity measured by the ABTS method yielded values higher than 718.99 µM trolox/g for dry plants, while by the Rancimat(®) system yielded protection factors exceeding 1 for all extracts, comparable to synthetic BHT. Ferulic acid was the principal phenolic compound identified and quantified through HPLC-UV in all extracts. The extracts proved effective inhibitory potential for Staphylococcus epidermidis and Staphylococcus aureus. These results showed that extracts of Euphorbia tirucalli L. have excellent antioxidant capacity and moderate antimicrobial activity. These can be attributed to the high concentration of ferulic acid.

Evaluation of antioxidant and mutagenic activities of honey-sweetened cashew apple nectar.

In vitro chemical properties and antioxidant potential and in vivo mutagenic activity of honey-sweetened cashew apple nectar (HSCAN), a beverage produced from the cashew pseudo-fruit (Anacardium occidentale L.) and of its constituents were assessed. Analytical procedures were carried out to investigate the honey used in the HSCAN preparation, and the results observed are in accordance with Brazilian legal regulations, except for diastase number. HSCAN and pulp were investigated for ascorbic acid, carotenoid, anthocyanin and total phenolic contents, and both showed high acid ascorbic concentrations. Antioxidant capacity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and/or ß-carotene/linoleic acid systems were applied and demonstrated a weak antioxidant capacity of honey and HSCAN, but cashew apple pulp demonstrated high antioxidant capacity. A weakly positive mutagenic effect of cashew pulp 20% was observed using the somatic mutation and recombination test (SMART) in Drosophila melanogaster only in the high-bioactivation (HB) cross. On the contrary, HSCAN was not mutagenic in both standard and high bioactivation crosses. HSCAN exhibited slight antioxidant activity, which could be associated with the high amount of ascorbic acid found in the samples evaluated. The beverage prepared did not induce DNA damage in somatic cells of D. melanogaster, which means that it is neither mutagenic nor recombinagenic in this test system.