Larvicidal activity against Aedes aegypti and molecular docking studies of compounds extracted from the endophytic fungus Aspergillus sp. isolated from Bertholletia excelsa Humn. & Bonpl.

Endophytic fungi are microorganisms capable of colonizing the interior of plant tissues without causing damage to them. The study of the secondary metabolites produced by their vast biodiversity fungal is relevant for the discovery of new products for biotechnological and agrochemical applications. In addition, extract of the endophytic fungus Aspergillus sp., isolated from the almonds of Bertholletia excelsa Humn & Bonlp collected in the Brazilian Amazon, oviposition deterrent, and larvicidal activity of against Aedes aegypti. In the oviposition deterrence test was observed that females able to lay eggs preferred the control oviposition sites (46.6%). Furthermore, the extract showed larvicidal activity with LC50 26.86 µg/mL at 24 h and 18.75 µg/mL at 48 h. Molecular docking studies showed the compound Aspergillol B a potent larvicide by to inhibit the acetylcholinesterase enzyme (- 7.74 kcal/mol). These results indicate that compounds from secondary metabolites of Aspergillus sp., isolated from almonds of B. excelsa, are useful biological potential against vectors A. aegypti.

Trichoderma asperellum Extract Isolated from Brazil Nuts (Bertholletia excelsa BONPL): In Vivo and In Silico Studies on Melanogenesis in Zebrafish.

Endophytic fungi are those that present part of their life cycle in healthy tissues of different plant hosts in symbiosis without causing harm. At the same time, fungus-plant symbiosis makes it possible for microorganisms to synthesize their own bioactive secondary metabolites while in the stationary stage. To accomplish this, the endophytic fungus Trichoderma asperellum was isolated from Bertholletia excelsa (Brazil nut) almonds. The fungus was cultivated and extracted with ethyl acetate, obtaining AM07Ac. Then, using HPTLC (High-performance thin-layer chromatography) and nuclear magnetic resonance (1H NMR), ß-amyrin, kaempferol, and brucine were identified as major compounds. Further in vivo assays in zebrafish demonstrated the activity of AM07Ac on melanogenesis by producing a concentration-response inhibitory effect, which, through an in silico study, proved to be related to the noted major compounds known to inhibit tyrosinase activity. The inhibition of tyrosinase prevents melanin accumulation in skin. Therefore, these results imply the importance of investigating microorganisms and their pharmacological activities, in particular the endophytic fungus Trichoderma asperellum as a generator of active metabolites for melanogenesis modulation.