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Arboviroses como Dengue, Zika, Chikungunya e Febre amarela têm sido um grande problema de saúde pública em regiões tropicais e subtropicais. O alto número de casos destas doenças é associado nessas regiões com a expansão geográfica do mosquito vetor que é pertencente ao gênero Aedes, em especial o A. aegypti. Com a falta de medicamento e principalmente de vacinas reconhecidas pela OMS, exceto a da Febre amarela, o controle populacional do mosquito vetor vem sendo a melhor forma de controle do avanço destas doenças. Realizamos uma breve revisão da literatura acerca destes métodos de controle tradicionais até os biotecnológicos para o controle do mosquito Aedes. Embora haja um esforço de aplicação dos métodos clássicos para controle do mosquito Aedes, os métodos biotecnológicos abrem novas perspectivas suprindo as baixas eficácias destes. Entre os métodos biotecnológicos, além da produção de mosquitos genéticamente modificados, destacam-se os métodos de alteração do microbioma larval por inserção da bactéria Wolbachia nos mosquitos. Esses métodos bastante promissores atuam na redução da população de mosquitos e na redução da proliferação dos vírus nos vetores, sendo, portanto, alternativas mais sustentáveis e que trazem consequentemente uma diminuição da Dengue e outras arboviroses em regiões endêmicas com menores impactos ambientais.

Bacillus are non-pathogenic gram-positive bacteria capable of producing resistant spores. They have several beneficial characteristics to crop production, such as increased plant growth, resistance to abiotic/biotic stresses, nutritional improvement, and potential for bioremediation of contaminated soils. The use of microorganisms in agriculture has increased due to the reduction in the use of agrochemicals, and sustainable production. Therefore, the present study was based on bibliographical research on the current state of the art of biotechnological prospecting and obtaining commercial products of Bacillus for the agricultural sector. The search was conducted through the Google Academic platform limiting the search to the years 2015 to 2020. Papers that explained in vitro or in vivo prospecting methodologies of Bacillus with promoter or protective activity of plants and those that described microbial inoculants with this genus were selected. Different species of Bacillus can modulate plant growth producing plant hormones. Molecular biology tools such as DNA sequencing and PCR are applied to the study of genes involved in plant growth modulation by Bacillus such as AcPho, ipdC and asbA. For the elaboration of agricultural bioproducts, vegetative structures or endospores are used, under an optimal concentration of 1 x 108 CFU/mL. In the face of species diversity, many have not yet been studied and are promising to become bioproducts. This fact is enhanced by the immeasurable applicability of Bacillus. Bacillus son bacterias grampositivas no patógenas capaces de producir esporas resistentes. Tienen varias características beneficiosas para la producción agrícola, como la promoción del crecimiento de las plantas, la resistencia al estrés abiótico/biótico, la mejora nutricional y el potencial de biorremediación de los suelos contaminados. El uso de microorganismos en la agricultura ha aumentado debido a la reducción del uso de pesticidas y la producción sostenible. Por lo tanto, el presente estudio se basó en la investigación bibliográfica sobre el estado actual del arte de la prospección biotecnológica y la obtención de productos de bacilo comercial para el sector agrícola. La búsqueda se realizó a través de la plataforma Google Academic, limitando la búsqueda a los años 2015 a 2020. Se seleccionaron artículos que explicaban metodologías de prospección de bacilos in vitro o in vivo con actividad promotora o protectora de plantas y aquellos que describían inoculantes con este género. Diferentes especies de Bacillus pueden modular el crecimiento de las plantas mediante la producción de hormonas vegetales. Las herramientas de biología molecular, como la secuenciación del ADN y la PCR, se aplican al estudio de genes implicados en la modulación del crecimiento de las plantas por Bacillus, como AcPho, ipdC y asbA. Para la elaboración de bioproductos agrícolas se utilizan estructuras vegetativas o esporas finales, bajo una concentración ideal de 1 x 108 UFC/mL. Dada la diversidad de especies, muchas aún no han sido estudiadas y prometen convertirse en bioproductos. Este hecho se ve reforzado por la inconmensurable aplicabilidad de Bacillus. Bacillus são bactérias gram-positivas não patogênicas capazes de produzir esporos resistentes. Possuem várias características benéficas à produção agrícola, como promoção do crescimento das plantas, resistência a estresses abióticos/bióticos, melhora nutricional e potencial de bioremediação de solos contaminados. O uso de microrganismos na agricultura tem aumentado devido à redução do uso de agrotóxicos e à produção sustentável. Portanto, o presente estudo baseou-se em pesquisas bibliográficas sobre o estado atual da arte da prospecção biotecnológica e da obtenção de produtos comerciais do Bacillus para o setor agrícola. A pesquisa foi realizada através da plataforma Google Acadêmico, limitada a busca aos anos de 2015 a 2020. Foram selecionados artigos que explicavam metodologias de prospecção in vitro ou in vivo de Bacillus com atividade promotora ou protetora de plantas e aqueles que descreviam inoculantes com esse gênero. Diferentes espécies de Bacillus podem modular o crescimento das plantas produzindo hormônios vegetais. Ferramentas de biologia molecular, como sequenciamento de DNA e PCR, são aplicadas ao estudo de genes envolvidos na modulação do crescimento vegetal pelo Bacillus, como AcPho, ipdC e asbA. Para a elaboração de bioprodutos agrícolas, são utilizadas estruturas vegetativas ou endósporos, sob uma concentração ideal de 1 x 108 UFC/mL. Diante da diversidade de espécies, muitos ainda não foram estudados e prometem se tornar bioprodutos. Este fato é potencializado pela aplicabilidade imensurável do Bacillus.

This study was to evaluate the biological activity of the extract of Botryosphaeria fabicerciana isolated from leaves of Morus nigra. The volatile compounds from the crude extract were analysed by GC-MS which demonstrate that mellein and β-orcinaldehyde were are the major compounds. The best minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract was observed against Gram-positive bacteria, with a MIC of 15.6 μg/mL towards B. cereus and MIC of 62.5 μg/mL towards S. aureus and B. subtilis. MBC values of 31.25 μg/mL, 62.5 μg/mL, and 250 μg/mL were observed towards B. cereus, B. subtilis, and S. aureus, respectively. The cytotoxicity analyses showed CC50 of 115 μg/mL. The crude extract showed antioxidant activity by the DPPH, ABTS, and FRAP assays. Therefore, the extract of the endophytic fungus presented biotechnological potential as an antibacterial and antioxidant agent.

The endophytic fungi live inside plant tissues and do not develop any disease to their hosts. These microorganisms can produce bioactive compounds. In this work, we aimed to evaluate the leaf endophytic fungi microbiota from J. brandegeana using the culture-dependent method and multilocus sequence analysis. The endophyte's isolation was performed by the fragmentation method and the MLSA phylogeny was made using ITS, elongation factor 1-α, β-tubulin, glyceraldehyde-3-phosphate and, actin genes. For the screening selection, agar piece test was performed and, amongst the strains, JB06 isolate was chosen for metabolic extraction from the fermented culture and the evaluation of the antibacterial, antioxidant, antiproliferative activities and, phenolic compounds assay. Through the MLSA analysis, there were five genera of fungi identified, with Colletotrichum the higher isolated. For the antioxidant assay using the fungal extract obtained from Mycoleptodiscus indicus (JB06), the best results were obtained with the ABTS method. Antiproliferative effects by the crude extract of the endophyte against the tumor hepatocellular carcinoma cells (HepG2/C3A) were found. In summary, our findings revealed highly diverse endophytic fungi associated with J. brandegeana, with the bioprospection of the endophyte M. indicus with biotechnological potential for the health field.

The protective and growth-promoting activities of Colletrotrichum and Diaporthe endophytes on tomato plants (Lycopersicon esculentum Mill.) are underexplored. We screened 40 endophytic fungi associated with Mexican shrimp plant (Justicia brandegeana) using an in vitro dual culture assay for Fusarium oxysporum, one of the most important phytopathogens of tomato plants. The three best antagonists, Colletotrichum siamense (JB224.g1), C. siamense (JB252.g1), and Diaporthe masirevicii (JB270), were identified based on multilocus sequence analysis. They were assessed in vitro for their inhibition of F. oxysporum and phosphate solubilisation capacity, and for the production of indole acetic acid. Greenhouse experiments verified the growth-promoting effects of these endophytes and the suppression of F. oxysporum symptoms in tomato plants. Under greenhouse conditions, the JB252.g1 and JB270 isolates showed positive results for seedling emergence speed. The radicular system depth of plants inoculated with JB270 was greater than that in uninoculated plants (27.21 vs 21.95 cm). The soil plant analysis development chlorophyll metre (SPAD) index showed statistically significant results, especially for the endophyte JB224.g1 (36.99) compared to the control plants (30.90) and plants infected solely with F. oxysporum (33.64).

In the present study, the biological activity of an extract of the secondary metabolites (E-G6-32) produced by the Curvularia sp. G6-32 endophyte (isolated from the medicinal plant Sapindus saponaria L.) was investigated. The antioxidant potential was confirmed by the DPPH (22.5%) and ABTS (62.7%) assays, and the total phenolic compound content was 40 µg gallic acid equivalents/mg. The extract E-G6-32 displayed good inhibitory activity toward butyrylcholinesterase (BuChE; IC50 = 110 ± 0.05 µg mL−1). The extract E-G6-32 was subjected to spectroscopic and mass spectrometry analyses. Comparison with the literature data confirmed that (-)-asperpentyn (1) was a major component. Asperpentyn belongs to the epoxyquinone family, which has attractive structural complexity, diverse functional groups, and a broad range of biological activities, including specific enzyme inhibitory activity. Our results suggest that Curvularia sp. G6-32 is a promising source of bioactive secondary metabolites and contains (-)-asperpentyn, which has potential pharmaceutical interest.

Endophytic microorganisms live inside the plant tissues symptomless. These microorganisma may present antagonistic activity against phytopathogens or produce metabolites with antifungal activity. We aimed to evaluate in vitro antagonism and competitive interactions between endophytic fungi of Diaporthe species and Sclerotinia sclerotiorum. We also carried out in vitro screening of antifungal activity of metabolic extracts of the two endophytes against the pathogen. The antagonism was performed by the paired-culture and two promising antagonists strains were selected for metabolic extraction from the fermented culture. Metabolic extracts were obtainment using two different organic solvents (Ethyl Acetate and Hexane) and their antifungal activity was carried out using the agar diffusion test. The in vitro antagonistic index ranged from 22.1 to 59.5%, with Diaporthe sp. PL03 (59.1%), D. schini PL40 (59.5%), D. infecunda PL63 (41.8%), D. anacardii PL64 (56.8%), with inhibition by mycelial contact. The endophytes PL01 (28.6%) and PL43 (28.5%), both D. anacardii, stood out blocking mycelial growth from a distance. In the antifungal assay, D. anacardii PL01 (31.7%) and D. schini PL40 (18.2%) acetate metabolite stood out. In summary, our results indicate a few Diaporthe endophytes able to antagonize a S. sclerotiorum pathogen under in vitro conditions.

The composition of endophytic communities is dynamic and demonstrates host specificity; besides, they have great intra- and interspecific genetic variability. In this work, we isolated leaf endophytic fungi from Serjania laruotteana, identify them using multilocus analysis, and evaluate the genetic variability using IRAP (inter-retrotransposon amplified polymorphism) and REMAP (retrotransposon-microssatellite amplified polymorphism). A total of 261 fungi were isolated and 58 were identified. Multilocus phylogenetic analysis using the partial sequences from the ITS1-5.8S-ITS2 regions, elongation factor 1-alpha, β-tubulin, actin, glyceraldehyde-3-phosphate dehydrogenase, and calmodulin genes identify that most strains belonged to the Colletotrichum and Diaporthe genera, other isolated genera were Xylaria, Phyllosticta, Muyocopron, Fusarium, Nemania, Plectosphaerella, Corynespora, Bipolaris, and Curvularia. The IRAP and REMAP analyzes were performed with Colletotrichum and Diaporthe genera and showed 100% of polymorphism and high intra- and interspecific variability. This is the first report of the diversity of endophytic fungi from S. laruotteana. In addition, it demonstrated that the IRAP and REMAP can be used to distinguish morphologically similar lineages, revealing differences even strains of the same species. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42770-021-00605-0.

Aspergillus nidulans is a fungal model organism extensively used in genetic approaches. It may reproduce sexually and asexually, with a well-defined parasexual cycle. The current paper demonstrates that the limitation of nitrogen source facilitates the production of A. nidulans's nonmeiotic recombinants directly from heterokaryons, without the recovery of the diploid phase. Heterokaryons formed between master strains were inoculated in sodium nitrate-low (basal medium [BM]) and sodium nitrate-rich media (minimal medium [MM]). All mitotic segregants produced by the heterokaryons were tested for their mitotic stability in the presence of benomyl, the haploidizing agent. Only mitotically stable haploid segregants were selected for subsequent analysis. Phenotypic analyses of such haploids favored the characterization of nonmeiotic recombinants. As the number of such recombinants was higher in BM than in MM, nitrogen limitation may have facilitated the isolation of nonmeiotic recombinants from heterokaryons by stimulating nuclear fusion still inside the heterokaryotic mycelium as a survival strategy.

The water is an essential resource for life on the planet and for human development. The textile industry is one of the anthropogenic activities that most consume water and pollute water bodies. Therefore, the present work aims to undertake a review on the main effects of the release of industrial dyes and the essential bioremediation mechanisms. The textile dyes significantly compromise the aesthetic quality of water bodies, increase biochemical and chemical oxygen demand (BOD and COD), impair photosynthesis, inhibit plant growth, enter the food chain, provide recalcitrance and bioaccumulation, and may promote toxicity, mutagenicity and carcinogenicity. In spite of this, the bioremediation of textile dyes, that is, the transformation or mineralization of these contaminants by the enzymatic action of plant, bacteria, extremophiles and fungi biomasses is fully possible. Another option is the adsorption. Despite some disadvantages, the bioremediation is essentially positive and can be progressively enhanced by modern biotechnological techniques that are related to the generation of more degrading and more resistant engineered organisms. This is a sustainable solution that provides a fundamental and innovative contribution to conventional physicochemical treatments. The resources of environmental biotechnology can, therefore, be used as tangible technological solutions for the treatment of textile dye effluents and are related to the ethical imperative of ensuring the minimum necessary for a quality life for the humankind. Keywords: Phytoremediation, Effluents, Ecotoxicity, Mutagenicity, Carcinogenicity, Microorganisms

Endophyte microorganisms have great biotechnological interest, with features applicable to different areas and are potentially useful in agriculture. The current study determines the biotechnological potential of endophytic fungi, isolated from leaves of Sapindus saponaria , to control phytopathogenic fungi and evaluate their enzyme production. Molecular taxonomy was performed by sequencing of the ITS1-5.8S-ITS2 ribosomal DNA region, identifying the genera Phomopsis, Sordariomycetes, Diaporthe, and Colletotrichum . In vitro antagonism against phytopathogens showed better results against Fusarium solani and provided inhibition indices between 41.8 % and 67.5 %. The endophytic strain SS81 ( Diaporthe citri ) presented the highest antagonism index against the pathogen. Against Glomerella sp. and Moniliophthora perniciosa, inhibition rates ranged between 18.7 % and 57.4 % and between 38.3 % and 64.8 %, respectively. Enzyme assays revealed that strain SS65 ( Diaporthe sp.) produced 1.16 UI µmol/min of amylase; strain SS77 ( Diaporthe sp.) produced 2.74 UI µmol/min of pectinase, and strain SS08 ( Diaporthe sp.) produced 1.51 UI µmol/min of cellulase. Thus, the current study shows evidence the importance of isolated endophytes with phytoprotective properties of plants with medicinal properties as alternatives for biological control and natural sources of products with biotechnological interest.

This study was to evaluate the biological activity of the extract of

Echeveria laui (Crassulaceae) is commonly commercialized due to its drought-tolerance capacity and to its rosette-shaped aesthetics. Since endophytes associated with plants from a dry or arid environment have scarcely been analyzed as yet, current research comprises the isolation of leaf endophytic bacteria from E. laui (one five-year-old and one two-year-old plants) investigating plant growth-promoting endophytic bacteria which may solubilize phosphate, fix nitrogen, produce exopolysaccharides/IAA and antagonize phytopathogens. Isolation by the maceration methodology provided a colonization rate of 1.98 x109 CFU g-1 for the two-year-old plant and 1.14 x 1010 CFU g-1 for the five-year-old one. All 40 isolates evaluated showed in vitro plant growth-promoting agent’s abilities, with emphasis on EG04, ELG18, and ELP06. The capacity of the three best bacterial isolates were evaluated under greenhouse conditions in common and black bean (Phaseolus vulgaris L.) plants. Based on the sequencing of the 16S rRNA region and phylogenetic analysis, the three endophytes were identified as Pantoea sp. (ELG04 and ELG18) and Erwinia sp. (ELP06). Under greenhouse conditions, statistically significant differences were found among the plants treated with the three endophytes when compared to control plants for fresh and dry shoot, root biomass and length. Echeveria laui (Crassulaceae) é comumente comercializada devido à sua capacidade de tolerância à seca e à sua estética em forma de roseta. Uma vez que endófitos associados a plantas de ambiente seco ou árido foram poucos explorados até então, este trabalho compreende o isolamento de bactérias endofíticas de folhas de E. laui (uma planta de cinco anos e uma de dois anos) investigando a capacidade de agente promotor do crescimento de plantas das bactérias endofíticas isoladas como solubilizar fosfato, fixar nitrogênio, produzir exopolissacarídeos/ AIA e antagonizar fitopatógenos. O isolamento pela metodologia de maceração proporcionou uma taxa de colonização de 1.98 x109 UFC g-1 para a planta de dois anos e 1.14 x 1010 UFC g-1 para a de cinco anos. Todos os 40 isolados avaliados mostraram habilidades do agente promotor de crescimento de plantas in vitro, com ênfase em EG04, ELG18 e ELP06. A capacidade dos três melhores isolados bacterianos foi avaliada em casa de vegetação em plantas de feijão preto e comum (Phaseolus vulgaris L.). Com base no sequenciamento da região 16S rRNA e análise filogenética, os três endófitos foram identificados como Pantoea sp. (ELG04 e ELG18) e Erwinia sp. (ELP06). Em casa de vegetação, diferenças estatisticamente significativas foram encontradas entre as plantas tratadas com os três endófitos quando comparadas às plantas controle para o peso fresco e seco da parte aérea e raízes, bem como para o comprimento da raiz.

Os insetos apresentam a maior biodiversidade entre a classe Animal e são fontes ricas de produtos biotecnológicos. Espécies da família Calliphoridae (Diptera) apresentam hábitos necrófagos durante a fase larval, assim são expostas a diferentes microrganismos, produzindo peptídeos antimicrobianos (AMPs) como sistema de defesa. O objetivo deste trabalho foi realizar um levantamento bibliográfico dos principais peptídeos antimicrobianos identificados em Calliphoridae (Diptera), fornecendo dados para a bioprospecção de novos compostos. A revisão bibliográfica foi realizada nas plataformas: Google Acadêmico e SciFinder e foram selecionados 56 artigos para o desenvolvimento deste trabalho. Os AMPs possuem atividade contra amplo espectro de bactérias gram-positivas e gram-negativas, por isso apresentam grande interesse para tratamentos de feridas (e.g.: Terapia Larval) e bioprospecção de novos antibióticos. Estas moléculas são obtidas a partir do produto de excreção e secreção das larvas de Calliphoridae e sua ação tem como alvo primário a membrana celular das bactérias, devido interações eletroestáticas e interações de van der Waals com a membrana lipídica. A utilização de técnicas de separação acopladas com espectrometria de massas permitiu a identificação e caracterização de peptídeos da classe Defensina em diferentes espécies de califorídeos. A bioprospecção de novas moléculas antimicrobianas em moscas é uma área promissora dentro da biotecnologia, devido ao aumento do número de bactérias resistentes aos antibióticos atuais.

Endophytes are growth-promoting agents capable of synthesizing phytohormones, uptaking nutrients, and controlling pathogens. There is a strong potential to exploit them in the agriculture field like biofertilizers and biocontrol agents. In this work, we aimed to evaluate endophytic fungi isolated from Pachystachys lutea for their potential to solubilize phosphate, synthesise indole acetic acid (IAA), antagonize phytopathogens, and promote plant growth under greenhouse conditions. The phosphate solubilization efficiency was assessed on Pikovskaya’s agar medium. For analysis of IAA production, mycelia plugs of endophytes were cultured in Potato Dextrose Broth medium supplemented with L-tryptophan, with Salkowski Reagent, and the absorbance of the culture was measured. The antagonism evaluation of strain Alternaria sp. PL75 against phytopathogens was performed using the paired-culture technique. The promotion of plant growth provided by Alternaria sp. PL75 was evaluated in tomato plants. All strains evaluated were able to solubilize phosphate; however, the strain Alternaria sp. PL75 was the most effective (4.29). Two strains, Nemania sp. PL27 and Alternaria sp. PL75, produced 1.86 and 1.73 μg mL-1 of IAA, respectively. In the antagonism assay, the endophyte Alternaria sp. PL75 and its fungal extract showed the best results against the pathogen Moniliophthora perniciosa. The greenhouse experiment result showed the endophyte Alternaria sp. PL75 increased the plantlets emergency speed index and the percentage of germination from 60 to 81.63%. It was also observed a statistical significance in the shoot length of the treated plants with the endophyte suspension (55.38 cm) compared to the control (41.67 cm). Endophytes are growth-promoting agents capable of synthesizing phytohormones, uptaking nutrients, and controlling pathogens. There is a strong potential to exploit them in the agriculture field like biofertilizers and biocontrol agents. In this work, we aimed to evaluate endophytic fungi isolated from Pachystachys lutea for their potential to solubilize phosphate, synthesise indole acetic acid (IAA), antagonize phytopathogens, and promote plant growth under greenhouse conditions. The phosphate solubilization efficiency was assessed on Pikovskaya’s agar medium. For analysis of IAA production, mycelia plugs of endophytes were cultured in Potato Dextrose Broth medium supplemented with L-tryptophan, with Salkowski Reagent, and the absorbance of the culture was measured. The antagonism evaluation of strain Alternaria sp. PL75 against phytopathogens was performed using the paired-culture technique. The promotion of plant growth provided by Alternaria sp. PL75 was evaluated in tomato plants. All strains evaluated were able to solubilize phosphate; however, the strain Alternaria sp. PL75 was the most effective (4.29). Two strains, Nemania sp. PL27 and Alternaria sp. PL75, produced 1.86 and 1.73 μg mL-1 of IAA, respectively. In the antagonism assay, the endophyte Alternaria sp. PL75 and its fungal extract showed the best results against the pathogen Moniliophthora perniciosa. The greenhouse experiment result showed the endophyte Alternaria sp. PL75 increased the plantlets emergency speed index and the percentage of germination from 60 to 81.63%. It was also observed a statistical significance in the shoot length of the treated plants with the endophyte suspension (55.38 cm) compared to the control (41.67 cm).

In this work, the antibacterial activity of a crude extract of the endophytic fungus Flavodon flavus (JB257), isolated from leaves of Justicia brandegeana, was evaluated against both the vegetative and sporulated forms of Alicyclobacillus acidoterrestris. The microdilution technique was performed in order to determine the antibacterial activity of the crude extract alone as well as in combination with the bacteriocin, nisin. The minimum inhibitory concentration (MIC) of the crude extract and nisin alone against A. acidoterrestris vegetative forms were 250 μg/mL and 31.5 μg/mL, respectively, while the minimum bactericidal concentrations (MBC) were 1000 μg/mL and 62.5 μg/mL,respectively. For A. acidoterrestris spores, treatment with the crude extract at a concentration of 500 μg/mL caused a 47% reduction in growth, while nisin at 62.5 μg/mL could reduce 100% of the growth. The in vitro evaluation of the crude extract combined with nisin against A. acidoterrestris by the Checkerboard method showed a synergistic interaction between the two compounds. In addition, greater selectivity towards bacterial cells over host cells, a human hepatocyte cell line, was achieved when the crude extract was combined with nisin, Using scanning electron microscopy, interferences in the cell membrane of A. acidoterrestris could be observed after treatment with the crude extract. The results presented in this study indicate that the crude extract of the endophyte F. flavus has biotechnological potential in the food industry, especially for the treatment of orange juices through the control of A. acidoterrestris.

Endophytes are microorganisms that form symbiotic relationships with their host. These microorganisms can produce a variety of secondary metabolites, some of which have inhibitory effects on pests and pathogens or even act to promote plant growth. Due to these characteristics, these microorganisms are used as sources of biologically active substances for a wide range of biotechnological applications. Based on that, the aim of this study was to evaluate the production of metabolites of the endophytic Aspergillus flavus CL7 isolated from Chromolaena laevigata, in four different cultivation conditions, and to determine the antimicrobial, cytotoxic, antiviral, and antioxidant potential of these extracts. The multiphasic approach used to identify this strain was based on morphology and ITS gene sequence analysis. The chemical investigation of A. flavus using potato dextrose and minimal medium, using both stationary and agitated methods, resulted in the isolation of kojic acid, α-cyclopiazonic acid, and 20,25-dihydroxyaflavinine. Another 18 compounds in these extracts were identified by UHPLC-HRMS/MS, of which dideacetyl parasiticolide A has been described for the first time from A. flavus. Aflatoxins, important chemomarkers of A. flavus, were not detected in any of the extracts, thus indicating that the CL7 strain is non-aflatoxigenic. The biological potential of all extracts was evaluated, and the best results were observed for the extract obtained using minimal medium against Trichophyton rubrum and Mycobacterium tuberculosis. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42770-021-00502-6.

BACKGROUND Bacillus thuringiensis (Bt) is a Gram-positive bacterium that synthesizes specific protein toxins, which can be exploited for control of various insect pests, including Diatraea saccharalis, a lepidopteran that severely damages sugarcane crops. Although studies have described the effects of Bt in the larval phases of D. saccharalis, few have examined its effect on insect eggs. Herein, we studied the entomopathogenic potential of Bacillus thuringiensis serovar Aizawai GC-91 (Bta) during D. saccharalis embryo development with the aim of understanding the entomopathogenic mechanism and developing new biological control techniques for target insects. RESULTS Bta concentrations of 5, 10 and 20 g L-1 demonstrated the strongest bioactivity, reducing D. saccharalis egg viability by 28.69%, 33.91% and 34.98%, respectively. The lethal concentrations (LCs) were estimated as: LC50 = 28.07 g L-1 (CI 95% = 1.89-2.38) and LC90 = 65.36 g L-1 (CI 95% = 4.19-5.26). Alterations in egg coloration, melanization and granule accumulation were observed at 24 h, persisting until 144 h. The embryo digestive systems were severely damaged, including narrowing of the intestinal lumen, vesiculations and degenerated cells, causing embryonic death. CONCLUSION The toxicity caused by Bta in D. saccharalis embryos demonstrated its potential as a biological control agent and as a sustainable alternative for integrated management of D. saccharalis infestation. © 2020 Society of Chemical Industry.

Made available in DSpace on 2020-12-12T01:35:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) We have previously reported that β-(1→3,1→6)-ᴅ-glucans produced by endophytes Diaporthe sp. G27-60 and G65-65 (GenBank accession codes JF766998 and JF767007, respectively) are promising anti-proliferation agents against human breast carcinoma (MCF-7) and hepatocellular carcinoma (HepG2-C3A) cells. However, the literature fails to describe the effects of Diaporthe exopolysaccharides (EPS) on eukaryotic healthy cells. The fungus Metarhizium anisopliae has been employed as model-system to evaluate the toxicity of pharmaceutical and agricultural-interest substances, taking into account, among other parameters, the speed of conidia germination. Current study verified the effect of different concentrations of Diaporthe β-glucans on the germination speed of M. anisopliae. Conidia were incubated with β-glucans treatments (50, 200 and 400 μg/mL) at 28ºC, sampled during 24 h and analyzed by light microscopy. At the end of a 24-h incubation, the amount of germinated conidia reached ≈99% for controls and ranged between 97.7 and 98.6% for treatments. Bayesian analysis indicated that Diaporthe glucans had no toxicity on M. anisopliae and the curve of germination occurred as expected for this fungal strain. Considering the validity of filamentous fungi as model-systems, results are important data on the toxicity of endophytic EPS on healthy cells and may be associated with our previous results obtained for these polymers against tumor cells. Universidade Estadual de Maringá (UEM) Universidade Católica Dom Bosco (UCDB) University of Georgia (UGA) Faculdade de Ciências e Tecnologia Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP) Núcleo Permanente Docente do Programa de Pós-graduação em Biotecnologia Ambiental da Universidade Estadual de Maringá (UEM) Faculdade de Ciências e Tecnologia Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) CNPq: 311534/2014-7 CNPq: 447265/2014-8

Endophytic microorganisms live inside the plants without causing any damage to their hosts. In the agricultural field, these endophytes might be a strategy of biological control for phytopathogens. We aimed to isolate endophytic fungi from yellow passion fruit (Passiflora edulis) leaves, evaluating its biocontrol capacity by in vitro antagonism against phytopathogen Colletotrichum sp. CNPU378. We also carried out greenhouse experiments in bean seedlings. A high colonization frequency was obtained (89%), and the molecular identification based on DNA sequencing attested Colletotrichum as the most frequent genus and minor occurrence of Curvularia endophytes. The endophytes tested showed different types of competitive interactions in in vitro antagonism inhibition rate ranging from 28.8 to 48.8%. There were 10 promising antagonists tested for their antagonist activity of crude extracts of secondary metabolites, in which strain PE-36 (20.8%) stood out among the other strains evaluated. In the greenhouse assay, plants inoculated only with endophyte Colletotrichum sp. PE-36 was symptomless and suggest that the endophyte strengthened the growth promotion in common bean plants, especially in the root length and number of leaves when compared to control plants and other treatments. Despite many fungi of Colletotrichum genus being described as causative agents of anthracnose, in this study, the plant sampled was colonized predominantly by Colletotrichum endophytes living in asymptomatic relationship. By the way, we come across a Colletotrichum sp. endophyte able to antagonize a Colletotrichum sp. pathogen.

Endoglucanases are enzymes widely employed in different industrial fields, albeit with high production costs. Studies on new microbial sources and low-cost substrates are highly relevant, including those on agro-industrial. Current analysis evaluates peanut hull (PH) and sawdust (SD) as substrates for submerged cultures of 14 endophytic fungi isolated from grapevine (Vitis labrusca L.) cultivars Bordô and Concord. Endophytes were grown on a carboxymethylcellulose (CMC) medium and the cup plate assay showed that eight strains (belonging to genera Cochliobolus, Diaporthe, Fusarium and Phoma) had positive results: enzymatic halos ranged from 10.8±0.02 to 15.5±0.07 mm in diameter. Diaporthe sp. strains (GenBank accession codes KM362392, KM362368 and KM362378) and Fusarium culmorum KM362384 were highlighted as the most promising sources. Further, PH and SD as substrates for the fermentation of these fungi were evaluated by the cup plate assay and endoglucanase activity assay. Highest halo diameters were obtained for Diaporthe sp. KM362392: 16.1±0.01 mm (CMC), 14.5±0.01 mm (PH) and 14.7±0.03 mm (SD). The fungus also presented the highest levels of endoglucanase activity: analysis of variance revealed that CMC (3.52±0.98 μmol/min), PH (2.93±0.23 μmol/min) and SD (3.26±0.38 μmol/min) were similarly efficient as substrates. Results deepen knowledge on V. labrusca endophytes that may be endoglucanase sources, even though further optimizations in submerged cultures with PH and SD should be undertaken to increase the enzymatic production from these wastes. Endoglucanases são enzimas amplamente empregadas em diferentes setores industriais; embora sua produção apresente custos elevados. Estudos sobre novas fontes microbianas e substratos mais baratos são de grande importância, incluindo os resíduos agroindustriais. Nesse estudo, casca de amendoim (CA) e serragem (SE) foram testadas como substratos para o cultivo submerso de 14 fungos endofíticos isolados das cultivares Bordô e Concord de videira (Vitis labrusca L.) Os endófitos foram crescidos em meio contendo carboximetilcelulose (CMC) e o ensaio cup plate mostrou resultados positivos para oito fungos (pertencentes aos gêneros Cochliobolus, Diaporthe, Fusarium and Phoma); os halos enzimáticos variaram entre 10,8±0,02 e 15,5±0,07 mm de diâmetro. Linhagens de Diaporthe sp. (códigos de acesso no GenBank KM362392, KM362368 e KM362378) e Fusarium culmorum KM362384 se destacaram como produtores mais promissores. Então, o uso de CA e SE como substratos para a fermentação desses fungos foi avaliado pelo ensaio cup plate e pela quantificação da atividade de endoglucanase. Os maiores halos enzimáticos foram obtidos para Diaporthe sp. KM362392: 16,1±0,01 mm (CMC), 14,5±0,01 mm (CA) e 14,7±0,03 mm (SE). Esse fungo também apresentou os maiores níveis de endoglucanase: a análise de variância revelou que CMC (3,52±0,98 μmol/min), CA (2,93±0,23 μmol/min) e SE (3,26±0,38 μmol/min) foram substratos similarmente eficientes. Esses resultados expandem o conhecimento sobre endófitos de V. labrusca que são fontes de endoglucanases; futuras otimizações quanto ao cultivo submerso com CA e SE podem ser utilizadas para aumentar a produção enzimática a partir do uso desses resíduos.

In the present study, the biological activity of an extract of the secondary metabolites (E-G6-32) produced by the