Anti-glycating and anti-oxidant compounds from traditionally used anti-diabetic plant Geigeria alata(DC) Oliv. & Hiern.

Abstract

A new sesquiterpene lactone geigerianoloide (1) and four known flavonoids axillarin (2), quercetin (3), 3-methoxy-5,7,3',4'-tetrahydroxy-flavone (4) and hispidulin (5) were isolated from Geigeria alata (DC) Oliv. & Hiern. (Asteraceae). Structures were deduced using ¹H- and ¹³C- NMR spectroscopy, mass spectrometry, while the structure of compound 1 was also deduced using X-ray crystallography technique.

Geigeria alata is traditionally used for diabetes, therefore compounds were tested for anti-glycation activity, in which compounds 2 and 3 showed potent activities (IC₅₀ values of 246.97 ± 0.83 and 262.37 ± 0.22 µM, respectively) compared to IC₅₀ value 294.50 ± 1.5 µM of rutin. Moreover, compound 4 exhibited a comparable activity to rutin (IC₅₀ = 293.28 ± 1.34 µM). Compound 5 showed a weak activity.

Compounds 2, 3, and 4 exhibited potent DPPH radical scavenging activity (IC₅₀ = 0.1 ± 0.00, 0.13 ± 0.00 and 0.15 ± 0.01 µM, respectively). Compounds 2, 3, and 4 demonstrated significant superoxide anion scavenging activity with IC₅₀ values of 0.14 ± 0.001, 0.17 ± 0.00, and 0.11 ± 0.006 µM, respectively.

Keywords:

• Anti-oxidant
• Anti-glycation
• axillarin
• Geigeriaalata (DC) Oliv. & Hiern.
• Geigerianoloide

Acknowledgements

This research work was conducted under ICCBS/TWAS Postgraduate Fellowship Award (FR Number 3240269304). We are also grateful for The World Academy of Sciences (TWAS) and the Higher Education Commission, Pakistan, for the financial support provided to Dr. Eltayeb Fadul. One of us (Arsalan Nizamani) also acknowledges Higher Education Commission, Pakistan, for financial support through “Indigenous 5000 Scholarship Programme Batch-VII”. Prof. Dr. M. Iqbal Choudhary gratefully acknowledges the IDB for financial support trough project entitled, “Developing the capacities of Al-Farabi Kazakh National University, Kazakhstan in Phytochemical Development” (Reference No. CAP/3370).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Islamic Development Bank; Higher Education Commission of Pakistan.