Kombucha Multimicrobial Community under Simulated Spaceflight and Martian Conditions

Area of Science:

• Astrobiology
• Biomaterials Science
• Microbiology

Background:

• Kombucha microbial community (KMC) produces bacterial cellulose, a valuable biopolymer and probiotic beverage.
• KMC-derived cellulose pellicle is a complex, stratified community of prokaryotes and eukaryotes, studied for astrobiological applications.
• The BIOlogy and Mars Experiment (BIOMEX) project investigates organism vitality and biomarker stability in space and Mars-like environments.

Purpose of the Study:

• Assess the structural integrity of bacterial cellulose as a biomarker and biotechnological nanomaterial under space conditions.
• Evaluate the survival capacity of KMC members and their cellulose production under simulated space stressors.
• Determine the impact of space exposure on microbial community structure and function.

Main Methods:

• Simulated 1-year exposure of KMC and its cellulose pellicle to space stressors (vacuum, Mars-like atmosphere, UVC, temperature fluctuations).
• Utilized culture-dependent and culture-independent methods to assess microbial survival, density, and richness.
• Analyzed chemical element accumulation in the cellulose-based pellicle post-exposure.

Main Results:

• KMC members exhibited high survival rates, with core bacteria and yeasts protecting against UV radiation.
• High-dose UV irradiation was identified as the critical limiting factor for microbial survival.
• Overall microbial density and richness were reduced, correlating with lower chemical element accumulation in the pellicle film.

Conclusions:

• KMC demonstrates resilience in space, but UV radiation poses a significant challenge to its structure and function.
• Bacterial cellulose integrity is maintained, but microbial community dynamics are altered by space exposure.
• Findings contribute to understanding microbial survival in extreme environments and the potential of bacterial cellulose as a biosignature and biomaterial.