From cultural and natural heritage to reservoir of biomedicine: Prospection of bioactive compounds produced by bacterial isolates from caves

9 páginas.- 5 figuras.- 2 tablas.- 50 referencias.- Supplementary data to this article can be found online at https://doi. org/10.1016/j.ibiod.2024.105773

Caves, with distinctive features and specialized ecosystems, harbour microorganisms that have adapted metabolically to survive in seemingly harsh conditions with limited essential elements. Despite the potential threat of biodeterioration to subterranean heritage due to microbial proliferation, caves serve as vital reservoirs of bioactive compounds produced by subsurface-adapted microorganisms. These microorganisms form biofilms, producing diverse bioactive compounds with properties such as antimicrobial, antioxidant, and anticancer capabilities. We conducted a comprehensive study with different bacterial strains isolated from terrestrial and marine caves (Escoural cave and in different caves on the Lanzarote island and on Selvagem Grande island). Extracts from these strains demonstrated potential in inhibiting the growth of pathogenic bacteria, showed robust antioxidant effects, and exhibited antiproliferative activity against breast cancer cells, moreover some of these extracts (Knoellia sp. CI04-s2.2, Brevibacillus sp. MR02B-s3, Bacillus sp. CK03-s2 and Bacillus sp. SD03-s6) present more than one bioactivity. This study unveiled the potential of cave bacterial strains as valuable sources of bioactive compounds, with implications for the development of novel biocides and pharmaceuticals. Bioprospecting within these unique environments offers a distinct opportunity not only to explore and safeguard these ecosystems but also to promote the development of eco-friendly, safe, and sustainable solutions.

The authors acknowledge financial support from FCT—Foundation for Science and Technology, I.P.—within the scope of the projects MICROCENO (DOI 10.54499/PTDC/CTA AMB/0608/2020), ART3mis (DOI 10.54499/2022.07303.PTDC), and R&D Units HERCULES Lab (UIDB/04449/2020), IN2PAST - Associate Lab (DOI 10.54499/LA/P/0132/2020) and CITAB (DOI 10.54499/UIDB/04033/2020), as well as the individual support to C. Salvador (DOI 10.54499/DL57/2016/CP1372/CT0019). The support of the PROBIOMA project (0483_PROBIOMA_5_E) EP-INTERREG V A Spain Portugal (POCTEP) is also acknowledged. This work also received support from the Spanish Ministry of Science and Innovation (MCIN) under the research project TUBOLAN PID2019-108672RJ-I00 funded by MCIN/AEI/10.13039/501100011033. The support from the intramural project PIE_20214AT021 funded by the Spanish National Research Council (CSIC) is also acknowledged. A.Z. Miller was supported by a CEEC contract (CEECIND/01147/2017/CP1431/CT0007) from FCT and then a Ramón y Cajal contract (RYC2019-026885-I) from the MCIN.

Peer reviewed