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Environmental Processing of Lipids Driven by Aqueous Photochemistry of ?-Keto Acids.

ABSTRACT: Sunlight can initiate photochemical reactions of organic molecules though direct photolysis, photosensitization, and indirect processes, often leading to complex radical chemistry that can increase molecular complexity in the environment. ?-Keto acids act as photoinitiators for organic species that are not themselves photoactive. Here, we demonstrate this capability through the reaction of two ?-keto acids, pyruvic acid and 2-oxooctanoic acid, with a series of fatty acids and fatty alcohols. We show for five different cases that a cross-product between the photoinitiated ?-keto acid and non-photoactive species is formed during photolysis in aqueous solution. Fatty acids and alcohols are relatively unreactive species, which suggests that ?-keto acids are able to act as radical initiators for many atmospherically relevant molecules found in the sea surface microlayer and on atmospheric aerosol particles.

SUBMITTER: Rapf RJ

PROVIDER: S-EPMC5968514 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Environmental Processing of Lipids Driven by Aqueous Photochemistry of α-Keto Acids.

Rapf Rebecca J RJ Perkins Russell J RJ Dooley Michael R MR Kroll Jay A JA Carpenter Barry K BK Vaida Veronica V

ACS central science 20180418 5

Sunlight can initiate photochemical reactions of organic molecules though direct photolysis, photosensitization, and indirect processes, often leading to complex radical chemistry that can increase molecular complexity in the environment. α-Keto acids act as photoinitiators for organic species that are not themselves photoactive. Here, we demonstrate this capability through the reaction of two α-keto acids, pyruvic acid and 2-oxooctanoic acid, with a series of fatty acids and fatty alcohols. We ...[more]

PMID: 29806009

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