Table 3 Enantiomeric compositions, expressed as l-enantiomeric excess (%ee_l), of selected amino acids detected in the water unhydrolyzed (UNH) extracts of the CI carbonaceous chondrite Orgueil, compared with amino acids measured in both unhydrolyzed and combined unhydrolyzed + hydrolyzed (HYD) Orgueil extracts^50,51

Unhydrolyzed treatment (UNH) refers to the extraction of amino acids using either successive cold and hot water (100 °C) extractions or hot water (100 °C) alone. In contrast, hydrolyzed treatment (HYD) involves extraction via HCl acid hydrolysis.
n.s.: Not separated. <LOQ: Both enantiomers were detected but remained below quantification limits. n.q.: Detected but not quantified due to chromatographic interference with other target analytes.
^a l-enantiomeric excess (%ee_l) was calculated as %ee_l = [(A_l-A_d)/(A_l+A_d) × 100], where A_l and A_d correspond to the ion peak areas for l- and d-enantiomers, respectively, obtained from single ion chromatograms at a specific m/z. Values represent the average ± standard deviation of n replicate injections: n = 9 except isovaline (n = 6). Negative %ee_l values indicate d-excesses.
^b Values represent the average ± standard deviation of 9 replicate injections corrected for procedural blank.
^c %ee_l values determined as %ee_l = [(C_l-C_d)/(C_l+C_d) × 100], where C_l and C_d correspond to the concentrations of the enantiomers reported by Burton et al.⁵⁰. Associated standard errors reported were propagated through first-order Taylor expansion approximation.
^d Data for the %ee_l correspond to the free (unhydrolyzed) plus bound (acid hydrolyzed) abundances reported by Glavin and Dworkin⁵¹.

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