Screening For Carotenoid-Producing Halophilic Bacteria Isolated From Saline Environments In Uzbekistan
Keywords:
Uzbekistan, halophiles, carotenoids, bacterioruberinAbstract
Uzbekistan’s salt-affected ecosystems are plausible reservoirs of halophilic prokaryotes capable of producing carotenoid pigments. The Aral Sea basin, partly within Uzbekistan’s Republic of Karakalpakstan, has markedly shrunk since the 1960s, exposing salt-rich sediments and creating harsh conditions that can enrich for stress-tolerant microbiota. In halophiles, carotenoids are associated with membrane stabilization, photoprotection, and mitigation of oxidative stress, including well-known C40 pigments (e.g., β-carotene, lycopene) and, in many haloarchaea, C50 bacterioruberin derivatives. This article presents an IMRAD-structured screening workflow suitable for Uzbekistan’s saline matrices (brines, sediments, salt crusts, saline soils). The approach integrates graded-salinity cultivation, pigment-stability checks, solvent extraction, UV–Vis fingerprinting focused on carotenoid absorption in the 450–550 nm window, and 16S rRNA identification, with confirmatory chromatography reserved for top candidates. The proposed pipeline prioritizes isolates based on convergent evidence rather than colony color alone, supporting resource-efficient discovery and the establishment of a local culture collection for downstream characterization and process development.
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