Thin-layer chromatography

About: Thin-layer chromatography is a research topic. Over the lifetime, 7494 publications have been published within this topic receiving 124179 citations. The topic is also known as: TLC.

Présence d'acides polyinsaturés dans une bactérie: isolement, à partir des lipides de Mycobacterium phlei, d'acide hexatriacontapentaène‐4,8,12,16,20oïque et d'acides analogues

Abstract: So far, bacteria were considered as devoid of polyunsaturated fatty acids. In spite of this assumption, the lipids of Mycobacterium phlei have a relatively high content (about 5% of the total free lipids) of acids with the general formula CH3–(CH2)n (CH=CH–CH2–CH2)m–CO2H (I), where n = 14 or 12 and m = 5, 6 or 4. The main component of this mixture is hexatriaconta 4,8,12,16,20-pentanoic acid. These acids can be isolated by saponification of the crude lipids, and detected by gas chromatography and thin layer chromatography on silver nitrate-impregnated silicagel. Their structure was established by means of spectrographic methods (infrared and ultraviolet spectrography, nuclear magnetic resonance and mass spectrometry), by study of the products obtained after oxidative degradation, and by comparison of the hydrocarbons prepared from these acids with synthetic hydrocarbons. The polyunsaturated acids are present in several complex lipids, including only a minor fraction of phospholipids. Because of their structure, the acids I belong to a new type of natural polyunsaturated fatty acids and might require a peculiar mode of biosynthesis, involving a repetition process.