Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Mar 14;27(6):1870.
doi: 10.3390/molecules27061870.

Using Taguchi Method to Determine the Optimum Conditions for Synthesizing Parapyruvate

Inn Lee  1 , Nae-Cherng Yang  1   2
Affiliations

Using Taguchi Method to Determine the Optimum Conditions for Synthesizing Parapyruvate

Inn Lee et al. Molecules. .

Abstract

The synthesis of parapyruvate is important for the analysis of the content in the pyruvate supplements and the study of aging-related neurodegenerative diseases. However, the pure parapyruvate crystal is not, as yet, commercially available. In this study, we applied the Taguchi's L9 orthogonal array to investigate the optimal conditions for the preparation of the pure parapyruvate by the alkaline treatment of the pyruvic acid and then followed it with the solvent crystallization steps. We were also interested in revealing the major factors that affect the yield for the synthesized pure parapyruvate crystals. In addition, the parapyruvate-inhibited enzyme kinetic of α-ketoglutarate dehydrogenase complex (KGDHC) was also investigated. We found that the pure parapyruvate could be obtained in combination with an alkaline treatment and two solvent crystallization steps. The main factors affecting the yield of the pure parapyruvate were the concentration of the pyruvic acid (the reactant), the pH of the alkali treatment, the type of solvent used for the crystallization and the volume ratio of solvent used for crystallization. Finally, the optimal conditions could prepare parapyruvate crystals with a high purity of 99.8% and a high yield of 72.8%. In addition, the results demonstrate that parapyruvate is a reversibly competitive inhibitor for KGDHC.

Keywords: KGDHC inhibitor; Taguchi’s L9 orthogonal array; optimal conditions; parapyruvate; yield.

PubMed Disclaimer

Conflict of interest statement

The authors declare that they have no conflict of interest.

Figures

Figure 1
Figure 1
The main plot effects for the signal-to-noise (S/N) ratios of (A) the CPSP preparation, the first solvent crystallization by (B) ethanol, (C) methanol, (D) acetone and (E) the secondary solvent crystallization by ethanol.
Figure 2
Figure 2
The inhibition kinetics of parapyruvate on the KGDHC. (A) Michaelis Menten plot. (B) Lineweaver–Burk plot.
Figure 3
Figure 3
The structures of (A) parapyruvate and (B) α-ketoglutarate.
See this image and copyright information in PMC

References

    1. Rios A.C., Bera P.P., Moreno J.A., Cooper G. Pyruvate Aldol Condensation Product: A Metabolite That Escaped Synthetic Preparation for Over a Century. ACS Omega. 2020;5:15063–15068. doi: 10.1021/acsomega.0c00877. - DOI - PMC - PubMed
    1. Chang S.-C., Lee I., Ting H., Chang Y.-J., Yang N.-C. Parapyruvate, an Impurity in Pyruvate Supplements, Induces Senescence in Human Fibroblastic Hs68 Cells via Inhibition of the α-Ketoglutarate Dehydrogenase Complex. J. Agric. Food Chem. 2018;66:7504–7513. doi: 10.1021/acs.jafc.8b01138. - DOI - PubMed
    1. Montgomery C.M., Webb J.L. Metabolic studies on heart mitochondria. II. The inhibitory action of parapyruvate on the tri-carboxylic acid cycle. J. Biol. Chem. 1956;221:359–368. doi: 10.1016/S0021-9258(18)65255-X. - DOI - PubMed
    1. Butterworth R.F., Besnard A.M. Thiamine-dependent enzyme changes in temporal cortex of patients with Alzheimer’s disease. Metab. Brain. Dis. 1990;5:179–184. doi: 10.1007/BF00997071. - DOI - PubMed
    1. Mastrogiacomo F., Lindsay J.G., Bettendorff L., Rice J., Kish S.J. Brain protein and α-ketoglutarate dehydrogenase complex activity in Alzheimer’s disease. Ann. Neurol. 1996;39:592–598. doi: 10.1002/ana.410390508. - DOI - PubMed

MeSH terms

LinkOut - more resources