The polyphenolics in the aqueous extract of Psidium guajava kinetically reveal an inhibition model on LDL glycation

Abstract

Guava [Psidium guajava L. (Myrtaceae)] budding leaf extract (PE) has shown tremendous bioactivities. Previously, we found seven major compounds in PE, i.e., gallic acid, catechin, epicatechin, rutin, quercetin, naringenin, and kaempferol. PE showed a potentially active antiglycative effect in an LDL (low density lipoprotein) mimic biomodel, which can be attributed to its large content of polyphenolics. The glycation and antiglycative reactions showed characteristic distinct four-phase kinetic patterns. In the presence of PE, the kinetic coefficients were 0.000438, 0.000060, 0.000, and −0.0001354 ABS-mL/mg-min, respectively, for phases 1 to 4. Computer simulation evidenced the dose-dependent inhibition model. Conclusively, PE contains a large amount of polyphenolics, whose antiglycative bioactivity fits the inhibition model.

Keywords::

• Antiglycation
• LDL glycation
• Psidium guajava L.

Acknowledgements

The authors are grateful for financial support from NSC-96-2320-B-241-006-MY3 and 94TMU-TMUH-02. The authors also acknowledge partial financial support of grant NHRI-EX95-916PN from The National Research Institute of Health and DOH95-TD-B-111-002 from The Ministry of Health, Taiwan.

Declaration of interest: The authors report no conflicts of interest.