Abstract
The rediscovery of bioactive compounds is a problem within natural product screening programs, because the chemical-genetic diversity of fungi is little explored and the standardization of cultivation conditions that allow obtaining new actives is critical in such programs. In this work, the impact of two solid mediums (rice and oats), a liquid medium (Czapeck broth) and different fermentation conditions were evaluated in order to explore new metabolic routes. Twelve filamentous fungi from Amazonian environments were used. UV-Vis spectrophotometry estimated the complexity of the extracts produced. The antimicrobial activity of the extracts was evaluated against an isolate of each Escherichia coli strain, Salmonella sp. and Staphylococcus aureus. Solid media proved to be more promising, as they allowed a wider range of active metabolites to be obtained. The oat medium provided a greater variety of metabolites, but due to the great complexity of the extracts obtained, the separation procedures were considerably more complex than for rice. Together, the rice culture medium and the use of 39 days of fermentation proved to be more promising conditions than the liquid medium normally used in screening programs in Brazil. The cultivation of Penicillium maximae (isolated for the second time in Brazilian territory) in solid medium provided the production of active fractions against E. coli in bioautography. In this study, it was observed that different fermentation conditions in solid culture are considerably promising in the search for bioactive natural products.
Highlights
Compounds isolated from biological sources represent the vast majority of drugs approved for clinical use, especially for cancer and infectious diseases (Dayanidhi et al, 2021; Atanasov et al, 2021)
Marked active fungi in preliminary studies were identified at molecular level as representative of the species: Penicillium maximae, Penicillium rolfsii, Aspergillus ochraceus, Aspergillus melleus and Fusarium oxysporum (Table 1)
Preliminary, it was observed that solid media appear to provide a more diverse range of antimicrobial active secondary metabolites when compared to liquid cultures
Summary
Compounds isolated from biological sources represent the vast majority of drugs approved for clinical use, especially for cancer and infectious diseases (Dayanidhi et al, 2021; Atanasov et al, 2021). One quarter of the therapeutic compounds were isolated from fungi (Berdy, 2012). These microorganisms synthesize compounds that may be the key to solving emerging public health problems (Raghava Rao, Mani, Satyanarayana & Raghava, 2017). An approach often known as OSMAC (One Strain Many Compounds) (Loffy et al, 2021), can have significant impacts on the quantity and diversity of secondary metabolites produced (Zutz et al, 2016). In an antimicrobial screening program in which a large number of filamentous fungi are to be screened, the OSMAC approach is not always viable, so the pursuit of a culture medium and condition that will allow more efficient production of new Antimicrobials become a necessity (VanderMolen, Raja, El-Elimat & Oberlies, 2013)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
