The Development and Perspectives of Bio-ISRU

Introduction: In-situ production of consumables using local resources (In-Situ Resource UtilizationISRU) will significantly facilitate current plans for human exploration and settlement of the solar system. With few exceptions [1], nearly all technology development to date has employed an approach based on inorganic chemistry [2]. None of these technologies include concepts for integrating the ISRU system with a bioregenerative life support system and a food production system. The investigation of Biotechnological (Bio) ISRU based on the metabolism of lower order photosynthetic organisms with ability to leach rocks and minerals appears to be very timely and relevant. Cyanobacteria (CB) are known as very effective producers of O2, proteins, vitamins, immunomodulators [3] and as very effective litholyts [4] to supply themselves with different elements. Using organic acids, bacteria are able to dissolve different rocks, including such hard rocks as volcanic glass [5], granites, hornblende, and basalts [6]. Bioweathering of lunar regolith has been considered by studies on the preparation of lunar-derived soil [7]. Because the Moon is practically free of organic compounds but is rich in inorganic elements, it makes sense to use autotrophic CB for future extraterrestrial biotechnologies [8]. Results: We have found that CB secrete organic acids when mixed with lunar regolith; secreted organic acids possess chelating properties. These chelators react with Fe in lunar minerals such as ilmenite (FeTiO3), ferrous oxides, and iron-bearing silicates (Fe2SiO4). Iron oxide interacts with acids liberating iron and generating water1 (equation. 1):