Research Article
Separation of Cyclic Dipeptides (Diketopiperazines) from Their Corresponding Linear Dipeptides by RP-HPLC and Method Validation
Table 3
Precision, accuracy, stability, and recovery for DKPs, dipeptides, and amino acids in crude extract of DSM 329.
| | Substance | Intrarun precision
(RSD %) | Interrun precision
(RSD %) | Accuracy (RE %) | Short-term stability (%) | Freeze-thaw stability (%) | Recovery
(%) |
| | Cyclo(Gly-Gly)/Gly-Gly | 1.1/0.9 | 0.7/2.6 | 4.7/7.7 | 100/99 | 97/98 | 97/99 | | Cyclo(L-Ala-L-Ala) and cyclo(D-Ala-D-Ala)/cyclo(L-Ala-D-Ala) | 1.1/0.7 | 3.5/0.9 | −0.3/8.1 | 99/101 | 99/98 | 99/99 | | L-Ala-L-Ala and D-Ala-D-Ala/L-Ala-D-Ala | 1.3/1.1 | 3.9/1.7 | 6.6/2.9 | 100/97 | 101/100 | 100/100 | | Cyclo(L-Arg-L-Arg)/L-Arg-L-Arg | 1.5/0.5 | 6.4/6.7 | 3.9/−0.3 | 102/99 | 101/99 | 100/98 | | Cyclo(L-Asp-L-Asp)/L-Asp-L-Asp | 1.0/1.1 | 1.3/1.9 | 5.1/2.1 | 100/101 | 100/98 | 101/98 | | Cyclo(L-Asp-L-Phe)/L-Phe | 1.1/1.5 | 3.0/3.1 | 2.2/2.3 | 102/100 | 98/98 | 100/98 | | L-Asp-L-Phe/L-Phe-L-Asp | 2.7/2.1 | 9.9/1.9 | 2.3/0.3 | 94/103 | 99/98 | 99/101 | | Cyclo(L-Pro-L-Tyr)/L-Tyr | 4.7/1.9 | 5.4/4.4 | 0.7/6.4 | 100/101 | 93/94 | 99/98 | | L-Pro-L-Tyr/L-Tyr-L-Pro | 1.4/1.3 | 4.5/2.0 | 4.3/−0.1 | 98/98 | 99/98 | 99/98 | | Cyclo(Gly-L-Phe)/L-Phe | 2.9/1.2 | 1.4/4.0 | −4.2/1.8 | 97/100 | 100/100 | 99/100 | | Gly-L-Phe/L-Phe-Gly | 1.3/0.9 | 3.4/2.7 | 0.3/−2.0 | 98/101 | 100/100 | 103/98 |
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