Precursors Of Fatty Alcohols In The ISM: Discovery Of n-propanol

By Keith Cowing
April 19, 2022
Filed under
Precursors Of Fatty Alcohols In The ISM: Discovery Of n-propanol

Theories on the origins of life propose that early cell membranes were synthesized from amphiphilic molecules simpler than phospholipids such as fatty alcohols. The discovery in the interstellar medium (ISM) of ethanolamine, the simplest phospholipid head group, raises the question whether simple amphiphilic molecules are also synthesized in space.

We investigate whether precursors of fatty alcohols are present in the ISM. For this, we have carried out a spectral survey at 7, 3, 2 and 1 mm toward the Giant Molecular Cloud G+0.693-0.027 located in the Galactic Center using the IRAM 30m and Yebes 40m telescopes. Here, we report the detection in the ISM of the primary alcohol n-propanol (in both conformers Ga-n-C3H7OH and Aa-n-C3H7OH), a precursor of fatty alcohols. The derived column densities of n-propanol are (5.5+-0.4)x10^13 cm^-2 for the Ga conformer and (3.4+-0.3)x10^13 cm^-2 for the Aa conformer, which imply molecular abundances of (4.1+-0.3)x10^-10 for Ga-n-C3H7OH and of (2.5+-0.2)x10^-10 for Aa-n-C3H7OH.

We also searched for the AGa conformer of n-butanol (AGa-n-C4H9OH) without success yielding an upper limit to its abundance of <4.1x10^-11. The inferred CH3OH:C2H5OH:C3H7OH:C4H9OH abundance ratios go as 1:0.04:0.006:<0.0004 toward G+0.693-0.027, i.e. they decrease roughly by one order of magnitude for increasing complexity. We also report the detection of both syn and anti conformers of vinyl alcohol, with column densities of (1.11+-0.08)x10^14 cm^-2 and (1.3+-0.4)x10^13 cm^-2, and abundances of (8.2+-0.6)x10^-10 and (9.6+-3.0)x10^-11, respectively. The detection of n-propanol, together with the recent discovery of ethanolamine in the ISM, opens the possibility that precursors of lipids according to theories of the origin of life, could have been brought to Earth from outer space. Izaskun Jimenez-Serra (1), Lucas F. Rodriguez-Almeida (1), Jesus Martin-Pintado (1), Victor M. Rivilla (1 and 2), Mattia Melosso (3), Shaoshan Zeng (4), Laura Colzi (1 and 2), Yoshiyuki Kawashima (5), Eizi Hirota (6), Cristina Puzzarini (3), Belen Tercero (7), Pablo de Vicente (7), Fernando Rico-Villas (1), Miguel A. Requena-Torres (8 and 9), Sergio Martin (10,11) ((1) Centro de Astrobiologia (CSIC/INTA), Ctra. de Torrejon a Ajalvir km 4, E-28806, Torrejon de Ardoz, Spain, (2) INAF-Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125, Florence, Italy, (3) Dipartimento di Chimica “Giacomo Ciamician”, Universita di Bologna, via F. Selmi 2,40126, Bologna, Italy, (4) Star and Planet Formation Laboratory, Cluster for Pioneering Research, RIKEN,2-1 Hirosawa, Wako, Saitama, 351-0198, Japan, (5) Department of Applied Chemistry, Faculty of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa 240-0292, Japan, (6) The Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193, Japan, (7) Observatorio de Yebes (IGN), Cerro de la Palera s/n, E-19141, Guadalajara, Spain, (8) University of Maryland, College Park, ND 20742-2421, USA, (9) Department of Physics, Astronomy and Geosciences, Towson University, MD 21252, USA, (10) European Southern Observatory, Alonso de Córdova 3107, Vitacura 763 0355, Santiago, Chile, (11) Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura 763 0355, Santiago, Chile) Comments: 15 pages, 10 figures, accepted for A&A
Subjects: Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:2204.08267 [astro-ph.GA] (or arXiv:2204.08267v1 [astro-ph.GA] for this version)
Submission history
From: Izaskun Jimenez-Serra
[v1] Mon, 18 Apr 2022 11:53:11 UTC (602 KB)
Astrobiology, Astrochemistry,

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻