In this study, we report the synthesis of acridone derivatives and their potential as photosystem II (PSII) inhibitors, as well as their preand post-emergence herbicidal activities through chlorophyll a fluorescence and germination assays. Among the compounds tested for PSII activity, acridin-9(10H)-one showed the most promising results, reducing the performance index on an absorption basis and decreasing the quantum yield for electron transport compared to the control. These findings suggest an inhibitory effect on PSII within the electron transport chain. Additionally, 2-chloroacridin-9(10H)-one and 9(10H)-acridone-4-carboxylic acid exhibited post-emergence herbicidal activity against Amaranthus lividus and Amaranthus viridis weeds, respectively, leading to a reduction in radicle and hypocotyl lengths. Furthermore, we applied a molecular docking approach with the D1 protein and 4-hydroxyphenylpyruvate dioxygenase to investigate the structure-activity relationships among the acridone derivatives with these enzymes. The analysis highlighted the importance of the carbonyl group and aromatic substituents on the acridone scaffold facilitating ligand interactions, especially through hydrogen bonding. Consequently, our research group aims to optimize these molecular features to develop new, potent bioactive molecular scaffolds.

This work describes the synthesis of two poly(lactic acid)-b-poly(ethylene glycol) copolymers (PLA-b-PEG), one containing folic acid, a targeting ligand, and the other containing fluorescein, a marker, both important in drug delivery systems. The copolymerization was carried out using the Ugi multicomponent reaction, which is a one pot reaction that involves the condensation of four components, an aldehyde or ketone, an amine, a carboxylic acid and an isocyanide. For this, poly(lactic acid) was functionalized with an aldehyde group (PLA-CHO) and poly(ethylene glycol) with an amine (PEG-NH2) and a carboxylic acid group (PEG-COOH), to be used in the Ugi reactions. From Fourier transform infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance (1H NMR) and ultraviolet-visible (UV-Vis) analyses, it was possible to confirm the synthesis of the block copolymers, in addition to the presence of both folic acid and fluorescein in the chemical structure of the materials. The work demonstrates that the Ugi reaction is an effective method to obtaining copolymers with different functionalities, and these materials have the potential to prepare micro and nanoparticles to be used in the controlled release of drugs.

There is a growing body of research on the use of liquid fuels in fuel cells, including glycerol. The direct oxidation of glycerol in an abiotic (traditional, conventional) fuel cell can not only be used to produce electrical energy, but also to obtain high value-added products. Furthermore, recent experimental studies have employed glycerol in biological fuel cells, which could contribute to transforming the biodiesel industry. Bacterial cultures have been used to degrade glycerol to produce electricity, while enzymatic processes have also employed glycerol to produce electricity and products of interest. This way, the main aim of this review is to survey the principal factors influencing the use of conventional and biological (enzymatic and microbial) fuel cells. A summary of the reports found in the literature is provided concerning the selectivity towards adsorbed intermediates and products generated during the oxidation of glycerol in conventional fuel cells. Not only experimental but also model-based aspects are addressed. For biological fuel cells, an overview of the enzymes and microorganisms used is presented, in addition to addressing the specific electron transfer mechanisms and other relevant aspects (such as challenges and limiting parameters for function and performance).

Herein, we developed a sensitive, selective, efficient, and low-cost method for higenamine (HG) detection. This method employs high-performance liquid chromatography with a chemiluminescence detector (HPLC-CL) coupled with an AgIII-luminol system. Lotus plumule and human urine samples were purified using a mixed weak cation exchange column (PWCX) solid-phase extraction cartridge, and a C18 column was employed for chromatographic separation using an aqueous solution of acetonitrile and 0.1% formic acid as the mobile phase. Under optimal conditions, the chemiluminescence (CL) signal decreased linearly with the logarithm of the concentration of HG in the range of 5-800 ng mL-1. The limit of detection (LOD) and limit of quantification (LOQ) of HG in the urine sample were 0.41 and 1.35 ng mL-1, respectively. The average recovery of HG in the urine and lotus plumule samples at three levels ranged from 80.02 to 110.40% with a relative standard deviation of less than 10%. Furthermore, we proposed a mechanism for CL signal reduction in the system. Finally, the urinary pharmacokinetics of HG in humans were studied to provide valuable information and reference for athletes on medication or diet during events.

The spread of antibiotic-resistant pathogens had motivated the search for plant-derived antimicrobial agents, such as essential oils. This work investigated the antibacterial, antifungal and antibiofilm properties of the essential oil from the inflorescence of Etlingera elatior and its major compounds. Dodecanal (42.46%) and 1-dodecanol (25.84%) were the major compounds. The oil, dodecanal and 1-dodecanol were active against Staphylococcus aureus, with minimum bactericidal concentrations of 124, 31 and 62 µg mL-1, respectively. For Pseudomonas aeruginosa, the essential oil had an inhibitory effect against a multidrug resistant isolate (minimum inhibitory concentration (MIC): 4,000 µg mL-1). Dodecanal had an MIC of 60,000 µg mL-1 for all Candida species, but fungicidal activity was only detected for Candida albicans (minimum fungicidal concentration: 60,000 µg mL-1). 1-Dodecanol (60,000 µg mL-1) exhibited fungistatic activity for C. albicans. Biofilm inhibition linked to an anti-adhesive effect of the oil and dodecanal was only detected for the standard S. aureus isolate and C. albicans, respectively. In conclusion, the essential oil from the inflorescence of E. elatior and its major components were more active against nonresistant strains S. aureus. Essential oil, dodecanol and dodecanal showed excellent activity against S. aureus, however, these same materials showed low activity against P. aeruginosa.

This work evaluated the elemental content and toxicology of the primary materials of the e-liquids without adding nicotine and other additives. Elemental content was determined through inductively coupled plasma mass spectrometry (ICP-MS) analyses, and biological effects were evaluated in Saccharomyces cerevisiae and H9c2 cells. Elemental analysis did not detect toxic elements above the limit of quantification (LOQ). Toxic concentration with significant difference (p < 0.05) between the samples and the non-exposed cells for glycerin (7.5% m/v) and propylene glycol (12.5% m/v) and at 70/30 proportions (12.5% m/v), 50/50 (12.5% m/v), and 30/70 (6.25% m/v) were encountered. Yeast toxicity presented a concentration-dependent relation with growth inhibition and lethality. Cytotoxicity tests in mammalian cells presented significant differences (p < 0.05) at low concentrations of glycerin and propylene glycol exposition (1.25 and 0.25% m/v, respectively). High concentrations of glycerin and propylene glycol induced increased reactive oxygen species/lactate dehydrogenase, decreased catalase activity, and interference in cell viability. On acute exposure, pure glycerin and propylene glycol are toxic for yeast and H9c2 cells, increasing with proportions of glycerin/propylene glycol and the increased amount of propylene glycol in the solution. No correlation between elemental content and toxicity was observed.

In this research, the phytochemical study of extracts from the leaves of Siparuna cymosa, an endemic species in Brazil, was carried out for the first time, and evaluated the cytotoxic activity of this extract against leukemia cell lines. The dried leaves were powdered and subjected to extraction by exhaustive maceration with pure organic solvents. The chloroform and ethyl acetate extracts were purified by column chromatography, and the isolated compounds were identified by spectroscopic techniques. The cytotoxic activity of extracts and compounds against THP-1 (acute myeloid) and K-562 (chronic myeloid) leukemia lines was determined using 3-(4,5-dimethyl-2-thyazolyl)-2,5-diphenyl-tetrazoliumbromide (MTT) assay. The isolated compounds were 1,5,6-trimethyl-8 oxabicyclo[3.2.1]oct-6-en-3-ol, β-sitosterol-3-O-β-D-glucopyranoside, and kaempferol-3,7 di-O-α-L-rhamnoside. This is the first report of isolation of oxabicyclo-octenol in plant species. β-Sitosterol-3-O-β-D-glucopyranoside and kaempferol-3,7-di-O-α-L-rhamnoside significantly reduced the viability of tumor cells after controlled exposure for 48 h. Moreover, selectivity was at least two times higher for such lineages compared to the results found for non-tumor peripheral blood cells (PBMC). Kaempferol-3,7-di-O-α-L-rhamnoside was the most active and selective. In conclusion, metabolites from S. cymosa showed to be of scientific interest. This study shows that the biodiversity of plant species in Brazil represents an important arsenal of organic compounds and, therefore, research should be motivated aiming at the isolation of secondary metabolites.

Antibiotic resistance raises concerns about their residues in food and the environment. To produce antibiotic-free dairy products, countries explore new strategies to reduce antibiotic doses in mastitis treatment. Lactoferrins (LF), iron-binding glycoproteins, exhibit species-specific glycosylation affecting their properties. While formulations of bovine lactoferrin have been tested with antibiotics showed synergistic properties increasing the antibacterial properties, other interactions of lactoferrin isoforms with antibiotics remain unclear. This study isolates, purifies, and characterizes buffalo lactoferrin (Bf-LF) and its interaction with amoxicillin. Bf-LF was purified using a Sephacryl S-100 column and monitored spectrofluorometrically. Spectroscopic analysis of Bf-LF interaction with amoxicillin reveals that increasing amoxicillin concentration reduces Bf LF fluorescence, indicating conformational changes. The Stern-Volmer quenching constant (KSV) and binding constant (Ka) measured at 298 K shows values around (2.79 ± 0.29) × 104 L mol-1 and (0.300 ± 0.04) × 104 L mol-1, respectively. UV-Vis spectroscopy shows a red shift (258.08 to 271.83 nm) implying Bf-LF-amoxicillin binding. In silico studies suggest polar interactions between amoxicillin and specific Bf-LF amino acids.

Spondias tuberosa (umbu) has been studied from the perspective of natural product and pharmacology, revealing relevant biological activities. Therefore, from the point of view of chemical and biological studies, deepening knowledge about this species is of great importance. Additionally, the evaluation related to the metabolic variations of the same species during different phenological evolution stages is also an interesting aspect of the research. Thereby, ultra performance liquid chromatography coupled to mass spectrometry (UPLC-QToF-MSE) was used to trace the chemical profile from umbu leaves at different phenological stages, allowing the detection of 40 metabolites, which 16 were annotated, such as phenolics and anacardic acids. Furthermore, the use of chemoinformatics tools allowed obtaining information on phenological development in the three leaves phases: post-flowering (young leaves), full production and senescence. The antiglycation activity assay revealed a potential inhibition of the formation of advanced glycation end-products (AGEs) in the leaves at different phenological stages. The antioxidant activity was satisfactory and in agreement with previously reported results, evidencing the potential for using umbu leaves, currently completely discarded, as an alternative source of antioxidants, which may provide increased added value to the cultivation of umbu, stimulating family farming and the recovery of tree density in degraded areas.

2,5-Diketopiperazines (2,5-DKPs) are valued in Medicinal Chemistry for their diverse properties and are considered privileged structures. The natural alkaloids class of fumiquinazolines, combining 2,5-DKP and quinazolinone cores within a pyrazino[1,2-b]quinazoline-3,6-dione framework, is known for its broad biological activity. Although few synthetic approaches to such structures have been explored, this study focuses on synthesizing novel fumiquinazolines analogs featuring a pyrazinopyrido[2,3-d]pyrimidine-5,7-dione core bearing various substituents on the pyrazine moiety (C-6 and C-9), classified into three series (A, B, and C). To investigate an efficient sequential one-pot method, we used a pyridine precursor and L-amino acids in two condensation and cyclization reactions, under controlled microwave irradiations at lower temperatures than previously reported. This approach generated protected bicyclic intermediates, particularly pyrido[2,3-d]pyrimidin-4(3H)-one derivatives, which were smoothly deprotected, allowing for final intramolecular cyclization to yield disubstituted fumiquinazoline analogs (series A) without observed epimerization. The optimized protocol revealed greater efficiency for monosubstituted analogs (series B and C), speeding up the tricyclic products synthesis without the need for intermediates isolation and deprotection. Overall, this study demonstrates the incorporation of diverse protected amino acids, featuring different electronic and structural side chains, via a rapid and effective sequential one-pot strategy, resulting in the synthesis of 19 novel fumiquinazoline analogs.

A simple, low-cost, and rapid analytical method for determination of the total phenolic content (TPC) in extra virgin olive oil samples (EVOOs) was developed, using digital images as an analytical tool. The method is based on an optimized Folin-Ciocalteu (F-C) colorimetric reaction, followed by digital image acquisition using a smartphone and processing with ImageJ® software to obtain red, green, and blue (RGB) values. The method was successfully validated, with recoveries between 73.11 and 112.65%, limits of detection (LOD) and quantification (LOQ) of 0.41 and 1.38 mg L-1, respectively. The TPC determined for eight EVOOs from different regions of the world were in the range of 186.38 to 378.87 mg gallic acid equivalent (GAE) kg-1, in accordance with some values reported in the literature. Statistical tests confirmed agreement between the results obtained using the digital image method and a reference method employing UV-Vis spectroscopy. The method complies with the principles of green chemistry, with reductions of cost, solvent use, and analysis time.

Human milk (HM) is recognized as an ideal nutritional source to meet the developmental needs of babies. However, a significant portion does not meet quality standards for immediate consumption, rendering it an interesting raw material for the production of by-products. This study aimed to evaluate the lipid composition and cytokines interleukin-10 (IL-10) and transforming growth factor-beta 1 (TGF-β1) in ice cream containing HM. Three formulations were developed: F1 with 93.46% HM, F2 with 46.73% cows’ milk and 46.73% HM, and F3 with 46.73% infant formula and 46.73% HM. Fatty acids (FA) and their nutritional quality, the triacylglycerol (TAG) profile, and the concentrations of cytokines IL-10 and TGF-β1 were analyzed. F1 and F3 exhibited the highest concentrations of essential FAs (18:2n-6 and 18:3n-3) compared to F2. This trend extended to eicosapentaenoic acid + docosahexaenoic acid, with higher values in F1 (10.62 ± 0.26) and F3 (11.16 ± 0.28) versus F2 (3.67 ± 0.18). Both cytokines IL-10 and TGF-β1, present in the ice creams, experienced a decrease in concentration due to the processing of the raw materials. Therefore, ice creams produced with HM have promising potential, making them recommended for use, providing a new destination for waste, and creating a novel product that can be used as a complementary food.

Our study on sustainable water management in sugarcane biorefineries, which utilizes water as a primary resource for generating bioenergy through steam production, has employed a novel approach. High water quality is crucial for optimal efficiency, particularly in boiler operations. We have utilized unsupervised methods, such as principal component analysis (PCA) and minimum spanning tree (MST), alongside instrumental analysis data, to assess water quality in steam production. The PCA exploratory analysis identified three distinct clusters, with the relevant variables being conductivity and SiO2 content, to differentiate the purity of a dataset of 120 samples. MST-based clustering corroborated the PCA findings, forming three clusters: sample 1 represented the purest water, while samples 3 and 6 were in different clusters, indicating less purity in boiler feedwater. These unsupervised methods are highly effective, providing accurate and reliable data analysis and significantly benefiting sugarcane biorefineries by eliminating subjective biases. The findings of this study promise to improve water management practices in sugarcane biorefineries, leading to more efficient and sustainable operations.

Plants of the genus Crotalaria are known for their antagonistic effect against nematodes. It has been found that pyrrolizidine alkaloids are the main metabolites involved in such antagonistic activity. Aiming at obtaining extracts with higher alkaloid content and enhanced potential for use as bionematicides, we investigated the chemical composition and nematicidal activity of extracts obtained from Crotalaria juncea and Crotalaria ochroleuca cultivated in vitro through micropropagation. Remarkably, extracts from the callus of C. ochroleuca (lethal concentration of 95% (LC95) = 157.7 μg mL-1) and C. juncea (LC95 = 189.9 μg mL-1) exhibited high toxicity against Meloidogyne javanica. The ultra performance liquid chromatography coupled to quadrupole time-of-flight with high mass spectrometry (UPLC-QTOF-MSE) analysis revealed the presence of pyrrolizidine alkaloids, flavones, flavone glycosides, and isoflavones. These findings highlight the potential of tissue culture to obtain extracts from Crotalaria species compared to conventionally cultivated plants and provide a higher concentration of metabolites with nematicidal effects, paving the way for sustainable agriculture.