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Jackfruit seeds have been explored as one interesting alternative starch source to be used in the production of sustainable bioplastics. In this context, this work aimed to investigate the effect of sorbitol concentration, one alternative plasticizer to glycerol, and the starch properties of the films. A complete factorial experimental study was done based on five different concentrations of starch (2, 3, 4, 5, and 6% w/w) and sorbitol (40, 50, 60, 70, 80 g per 100 g of starch). The films were produced by casting technique and were characterized about thickness, optical properties, moisture resistance, mechanical properties, and morphology. The optical properties revealed opaque films, with opacity values ranging from 16.04 to 21.26%. Regarding moisture resistance, the less hydrophilic films showed lower plasticizer content. The water solubility varied from 25.48 to 38.93%; the water vapor permeability ranged from 9.99 to 11.82 × 10 −9 (g/m s Pa) and the free energy of hydrophobic interactions varied from − 28.16 to 40.13 mJ m −1 . Concerning the mechanical properties, the tensile strength of the films ranged from 3.55 to 9.25 MPa, and increasing the sorbitol concentration decreased the tensile strength and increased the elongation at break. The morphology and structure analysis showed that starch granules were not fully gelatinized, with microbubbles and grooves in the film matrix. This study showed the great potential of jackfruit seed starch and sorbitol in the manufacture of biodegradable films as alternative sustainable packaging.

The conversion of lignocellulose into fermentable sugars is considered a promising alternative for increasing ethanol production. Higher fermentation yield has been achieved through the process of simultaneous saccharification and fermentation (SSF). In this study, a comparison was performed between the yeast species Saccharomyces cerevisiae and Kluyveromyces marxianus for their potential use in SSF process. Three strains of S. cerevisiae were evaluated: two are widely used in the Brazilian ethanol industry (CAT-1 and PE-2), and one has been isolated based on its capacity to grow and ferment at 42 °C (LBM-1). In addition, we used thermotolerant strains of K. marxianus. Two strains were obtained from biological collections, ATCC 8554 and CCT 4086, and one strain was isolated based on its fermentative capacity (UFV-3). SSF experiments revealed that S. cerevisiae industrial strains (CAT-1 and PE-2) have the potential to produce cellulosic ethanol once ethanol had presented yields similar to yields from thermotolerant strains. The industrial strains are more tolerant to ethanol and had already been adapted to industrial conditions. Moreover, the study shows that although the K. marxianus strains have fermentative capacities similar to strains of S. cerevisiae, they have low tolerance to ethanol. This characteristic is an important target for enhancing the performance of this yeast in ethanol production.

The intermediate disturbance hypothesis (IDH) has been thoroughly investigated, but much controversy has been found for supporting its assumptions, which rely largely on the nature of the disturbance, spatial scale, and biological predictors tested. In this paper, richness of native and non-native species along a suite of Neotropical aquatic ecosystems across a broad latitudinal and geographical range was used to test the IDH predictions. An extensive literature survey was performed to compile native species richness and the occurrence of several taxonomic groups listed as non-native for twenty-four coastal rivers and bays evenly distributed into three climatic zones (tropical, transitional, and subtropical). The climatic gradient was confirmed by NMDS and PERMANOVA, but IDH predictions were only significantly supported for native and total species richness in the coastal bays. The distribution patterns of non-native marine species showed a linear instead unimodal pattern of increase with latitudinal climatic gradient, but the responses are complex and dependent of many non-exclusive factors, such as the sampling effort per ecosystem and the potential interference of other disturbance gradients that should be further addressed to unravel the role of IDH for non-native species distribution.

Aquatic birds are the natural reservoir for avian influenza viruses (AIV). Habitats in Brazil provide stopover and wintering sites for water birds that migrate between North and South America. The current study was conducted to elucidate the possibility of the transport of influenza A viruses by birds that migrate annually between the Northern and Southern Hemispheres. In total, 556 orotracheal/cloacal swab samples were collected for influenza A virus screening using real-time RT-PCR (rRT-PCR). The influenza A virus-positive samples were subjected to viral isolation. Four samples were positive for the influenza A matrix gene by rRT-PCR. From these samples, three viruses were isolated, sequenced and characterized. All positive samples originated from a single bird species, the ruddy turnstone (Arenaria interpres), that was caught in the Amazon region at Caeté Bay, Northeast Pará, at Ilha de Canelas. To our knowledge, this is the first isolation of H11N9 in the ruddy turnstone in South America.

The understanding that zidovudine (ZDV or azidothymidine, AZT) inhibits the RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 and that chalcogen atoms can increase the bioactivity and reduce the toxicity of AZT has directed our search for the discovery of novel potential anti-coronavirus compounds. Here, the antiviral activity of selenium and tellurium containing AZT derivatives in human type II pneumocytes cell model (Calu-3) and monkey kidney cells (Vero E6) infected with SARS-CoV-2, and their toxic effects on these cells, was evaluated. Cell viability analysis revealed that organoselenium (R3a–R3e) showed lower cytotoxicity than organotellurium (R3f, R3n–R3q), with CC50 ≥ 100 µM. The R3b and R3e were particularly noteworthy for inhibiting viral replication in both cell models and showed better selectivity index. In Vero E6, the EC50 values for R3b and R3e were 2.97 ± 0.62 µM and 1.99 ± 0.42 µM, respectively, while in Calu-3, concentrations of 3.82 ± 1.42 µM and 1.92 ± 0.43 µM (24 h treatment) and 1.33 ± 0.35 µM and 2.31 ± 0.54 µM (48 h) were observed, respectively. The molecular docking calculations were carried out to main protease (Mpro), papain-like protease (PLpro), and RdRp following non-competitive, competitive, and allosteric inhibitory approaches. The in silico results suggested that the organoselenium is a potential non-competitive inhibitor of RdRp, interacting in the allosteric cavity located in the palm region. Overall, the cell-based results indicated that the chalcogen-zidovudine derivatives were more potent than AZT in inhibiting SARS-CoV-2 replication and that the compounds R3b and R3e play an important inhibitory role, expanding the knowledge about the promising therapeutic capacity of organoselenium against COVID-19.

Anti-tumour inflammatory cytokines are highly toxic when administered systemically. Here, in multiple syngeneic mouse models, we show that the intratumoural injection of recombinantly expressed cytokines bound tightly to the common vaccine adjuvant aluminium hydroxide (alum) (via ligand exchange between hydroxyls on the surface of alum and phosphoserine residues tagged to the cytokine by an alum-binding peptide) leads to weeks-long retention of the cytokines in the tumours, with minimal side effects. Specifically, a single dose of alum-tethered interleukin-12 induced substantial interferon-γ-mediated T-cell and natural-killer-cell activities in murine melanoma tumours, increased tumour antigen accumulation in draining lymph nodes and elicited robust tumour-specific T-cell priming. Moreover, intratumoural injection of alum-anchored cytokines enhanced responses to checkpoint blockade, promoting cures in distinct poorly immunogenic syngeneic tumour models and eliciting control over metastases and distant untreated lesions. Intratumoural treatment with alum-anchored cytokines represents a safer and tumour-agnostic strategy to improving local and systemic anticancer immunity. The intratumoural injection of recombinantly expressed cytokines bound tightly to the common vaccine adjuvant aluminium hydroxide leads to weeks-long retention of the cytokines in the tumours with minimal side effects, as shown in multiple syngeneic mouse models.

This study employs electrochemical and Density Functional Theory (DFT) calculation approaches to investigate the potential of a novel analogue of trimetozine (TMZ) antioxidant profile. The correlation between oxidative stress and psychological disorders indicates that antioxidants may be an effective alternative treatment option. Butylatedhydroxytoluene (BHT) is a synthetic antioxidant widely used in industry. The BHT-TMZ compound derived from molecular hybridization, known as LQFM289, has shown promising results in early trials, and this study aims to elucidate its electrochemical properties to further support its potential as a therapeutic agent. The electrochemical behavior of LQFM289 was investigated using voltammetry and a mechanism for the redox process was proposed based on the compound’s behavior. LQFM289 exhibits two distinct oxidation peaks: the first peak, Ep1a ≈ 0.49, corresponds to the oxidation of the phenolic fraction (BHT), and the second peak, Ep2a ≈ 1.2 V (vs. Ag/AgCl/KClsat), denotes the oxidation of the amino group from morpholine. Electroanalysis was used to identify the redox potentials of the compound, providing insight into its reactivity and stability in different environments. A redox mechanism was proposed based on the resulting peak potentials. The DFT calculation elucidates the electronic structure of LQFM289, resembling the precursors of molecular hybridization (BHT and TMZ), which may also dictate the pharmacophoric performance.

A new protocol for the preparation of thioaryl-porphyrins is described. The compounds were prepared from different disulfides employing NaBH4 as a reducing agent. The methodology allowed the preparation of four different thioaryl-porphyrins in very-good to excellent yields under soft conditions, such as short reaction times and smooth heating. Additionally, the photophysical properties of new compounds were determined and experimental and theoretical DNA interactions were assessed.

Here, we describe 4-dimethylaminoantipyrine (4-DMAA)-mediated interfacing as a broad biochemical indicator to stabilize and promote the higher response of electrodes for immunological detection. We hypothesized that the improved biological interactions of 4-DMAA with electrodes and biological samples may be due to the interaction properties of the benzene and pyrazole chemical groups with graphite and proteins, respectively. In order to demonstrate that 4-DMAA could be used as a general indicator in electrochemical immunoassays, we used peptides as probes for the diagnosis of four neglected tropical infectious diseases Tegumentary leishmaniasis, Visceral leishmaniasis, Strongyloidiasis, and Leprosy on commercial graphite screen-printed electrodes. 4-DMAA oxidation was used to indicate specific biological recognition between the epitope-based peptide and serum immunoglobulin G (IgG) from infected patients. We demonstrated that 4-DMAA should be incorporated into the electrodes prior to serum application, which avoids interference with its sensitivity and specificity. In addition, 4-DMAA oxidizes at a low anodic potential, and the oxidation peak is useful for detecting proteins in biological fluids. In summary, we have successfully demonstrated the broad application of 4-DMAA as a general indicator for the specific diagnosis of four infectious diseases in electrochemical immunosensors. Such a strategy is quite advantageous for indirect detection of proteins that lack electrochemical activities or are spatially inaccessible on the electrode surface. This new indicator opens a new avenue for monitoring biological recognition, especially for immunosensors.

A straightforward and high-yielding methodology for the synthesis of a high structural diversity of 1,2,4-oxadiazoles from different chiral N-protected α-amino acids and amidoximes under microwave (MW) irradiation is described herein. This greener approach gives the desired products using acetone/water as solvent in very short reaction times.