Antitumor and antibacterial activity of metabolites of endophytic Colletotrichum siamense isolated from coffee (Coffea arabica L. cv IAPAR-59).

Endophytic fungi produce a range of known metabolites and several others, not yet explored, which present important biological activities from the pharmaceutical and industrial perspective. Several studies have reported the diversity of endophytes in Coffea arabica plants, although few have been described in organic cultures. In the current paper, we describe the chemical profile of specialized metabolites in the ethyl acetate phase in a strain of the endophytic fungus Colletotrichum siamense associated with coffee (Coffea arabica L.) (Rubiaceae) and its potential against tumor cells and bacteria of medical and food importance. Cytotoxicity assays in tumor cells MCF-7 and HepG2/C3A were performed by MTT and microdilution in broth to evaluate the antibacterial action of metabolic extract. The antiproliferative assay showed promising results after 24 h of treatment, with 50% injunction concentrations for the two cell types. UHPLC-MS/MS analyses with an electrospray ionization source were used to analyze the extracts and identify compounds of species Colletotrichum siamense, which is still little explored as a source of active metabolites. Many of these compounds observed in the endophytic need to be chemically synthesized in industry, at high costs, while production by the fungus becomes a chemically and economically more viable alternative. Pyrocatechol, gentisyl alcohol, and alpha-linolenic acid, associated with different mechanisms of action against tumor cells, were detected among the main compounds. The extract of the endophytic fungus Colletotrichum siamense presented several compounds with pharmacological potential and antibacterial activity, corroborating its potential in biotechnological applications.

Synthesis, characterization, and reusability of novel nanobiocomposite of endophytic fungus Aspergillus flavus and magnetic nanoparticles (Fe3O4) with dye bioremediation potential.

The incorrect disposal of textile dyes, such as Reactive Black 5 (RB5), causes several problems for living beings and the quality of the environment. Nanobiocomposites (NBC) produced from endophytic fungi (potentially remediation dyes-agents) and magnetic nanoparticles have high biotechnological potential due to their superparamagnetic behavior, which would allow their recovery through the magnetic field after the bioremediation process. This work aimed to obtain a new nanobiocomposite from the interaction of magnetite nanoparticles (Fe3O4) with the endophyte Aspergillus flavus (Af-CL-7) to evaluate its bioremediation capacity and to reduce the toxicity of RB5 and its reuse. Before obtaining the NBC, Af-CL-7 showed discoloration of RB5 and it was tolerant to all tested concentrations of this dye. The discovery of the nanobiocomposite textile dye bioremediator product presents a significant environmental advantage by addressing the issue of water pollution caused by textile dyes. The NBC called Af-Fe3O4 was successfully obtained with the magnetized endophyte, and their magnetic properties were verified by VSM analysis and by action of magnetic fields generated by Nd-Fe-B magnets SEM analyzes showed that the nanoparticles did not cause any damage to the hypha morphology, and TEM analyzes confirmed the presence of nanoparticles in the fungus wall and also inside the cell. The NBC Af-Fe3O4 and Af-CL-7 showed, respectively, 96.1% and 92.2% of RB5 discoloration in the first use, 91.1% e 86.2% of discoloration in the validation test, and 89.0% in NBC reuse. In the toxicological bioassay with Lactuca sativa seeds, NBC showed a positive reduction in the toxicity of RB5 after treatment, allowing the hypocotyl growth to be statistically similar to the control with water. Thus, we highlight the promising obtaining process of NBC that could be applied in bioremediation of contaminated waters, wherein the industrial economic cost will depend on the fermentation efficiency, biomass production and nanoparticle synthesis.

Molecular techniques for the taxonomy of Aedes Meigen, 1818 (Culicidae: Aedini): A review of studies from 2010 to 2021.

The original description of Aedes Meigen in 1818, written in Latin, was very brief and included a single species, Aedes cinereus. In the last two decades the genus Aedes (Meigen, 1818) has undergone several revisions and reclassifications, with the current proposal being described by Wilkerson in 2015. However, the available keys for morphological identification are still not sufficient to differentiate cryptic species, damaged species, or those with confusing taxonomy. The current study aims to identify and describe the main taxonomic proposals and molecular methodologies available for the identification of the genus Aedes published between the years 2010 and 2021. The main molecular techniques used to identify the genus in the last 10 years, are: Multiplex PCR, DNA barcoding, nuclear and mitochondrial markers, environmental DNA, and bacterial microbiome analysis. This review highlights that there are catalogued data for only a few species of the genus Aedes, being restricted to medically important taxa such as Aedes albopictus and Aedes aegypti. The integrative taxonomy approach is a possibility to reconcile morphological and molecular data to improve species delimitation, contributing to future revisions of the genus.

Differential Chemical Profile of Metabolite Extracts Produced by the Diaporthe citri (G-01) Endophyte Mediated by Varying the Fermented Broth pH.

Endophytic microorganisms show great potential for biotechnological exploitation because they are able to produce a wide range of secondary compounds involved in endophyte−plant adaptation, and their interactions with other living organisms that share the same microhabitat. Techniques used to chemically extract these compounds often neglect the intrinsic chemical characteristics of the molecules involved, such as the ability to form conjugate acids or bases and how they influence the solubilities of these molecules in organic solvents. Therefore, in this study, we aimed to evaluate how the pH of the fermented broth affects the process used to extract the secondary metabolites of the Diaporthe citri strain G-01 endophyte with ethyl acetate as the organic solvent. The analyzed samples, conducted by direct-infusion electrospray-ionization mass spectrometry, were grouped according to the pH of the fermented broth (i.e., <7 and ≥7). A more extreme pH (i.e., 2 or 12) was found to affect the chemical profile of the sample. Moreover, statistical analysis enabled us to determine the presence or absence of ions of high importance; for example, ions at 390.7 and 456.5 m/z were observed mainly at acidic pH, while 226.5, 298.3, and 430.1 m/z ions were observed at pH ≥ 7. Extraction at a pH between 4 and 9 may be of interest for exploring the differential secondary metabolites produced by endophytes. Furthermore, pH influences the chemical phenotype of the fungal metabolic extract.

Endophytic Fungi as a Source of Antiviral Compounds - A Review.

Endophytic fungi are a rich source of secondary metabolites. The interactions between endophytes and their hosts lead to the production of several bioactive substances grouped into different classes, each having a wide variety of effects against various pathogens. The metabolites obtained from these organisms include steroids, alkaloids, phenols, isocoumarins, xanthones, quinones, and terpenoids, among others. These substances are known to have antibiotic, antiparasitic, antifungal, and antiviral effects. This review summarizes secondary metabolites with antiviral effects produced by endophytic fungi and highlights the importance of research in developing novel antiviral substances. We demonstrate that endophytic fungi are a rich source of secondary metabolites that combat pathologies caused by viruses. Optimizing practical and biotechnological screening tools for the research of these metabolites will provide promising drugs to combat these infections.

Influence of abiotic factors on the oviposition of Aedes (Stegomyia) aegypti (Diptera: Culicidae) in Northern Paraná, Brazil.

Aedes aegypti is the main vector of dengue in the Americas and is also a transmitter of urban yellow fever arboviruses, Zika, and Chikungunya, all of which have substantial economic impacts on the affected countries. Through mathematical models, the influence of climatic factors on the oviposition of Ae. aegypti was determined. The data were collected in the city of Apucarana, Paraná State, using oviposition traps. Daily data were submitted to a negative binomial regression model (p < 0.05). The analyses were performed using the R statistical program to determine the climatic factors that most influenced oviposition. A Poisson regression showed that the variables temperature, atmospheric pressure, humidity, and precipitation significantly increased the number of eggs. However, using the semi-normal probability graph with a simulation envelope, it was determined that the Poisson regression model was not adequate to explain the relationships between the variables. Thus, a negative binomial regression model was used, which overcame the problem of overdispersion, and showed that only temperature affected the increase in the number of eggs, where an increase of 1 °C was expected to result in a 54.03% increase in the number of Ae. aegypti eggs.