Phytochemical Characterization of Dillenia indica L. Bark by Paper Spray Ionization-Mass Spectrometry and Evaluation of Its Antioxidant Potential Against t-BHP-Induced Oxidative Stress in RAW 264.7 Cells

Md Badrul Alam; Arif Ahmed; Syful Islam; Hee-Jeong Choi; Md Abdul Motin; Sunghwan Kim; Sang-Han Lee

doi:10.3390/antiox9111099

Phytochemical Characterization of Dillenia indica L. Bark by Paper Spray Ionization-Mass Spectrometry and Evaluation of Its Antioxidant Potential Against t-BHP-Induced Oxidative Stress in RAW 264.7 Cells

Antioxidants (Basel). 2020 Nov 9;9(11):1099. doi: 10.3390/antiox9111099.

Authors

Md Badrul Alam^{1

2}, Arif Ahmed³, Syful Islam³, Hee-Jeong Choi¹, Md Abdul Motin⁴, Sunghwan Kim^{3

5}, Sang-Han Lee^{1

2

6}

Affiliations

¹ Department of Food Science and Biotechnology, Graduate School, Kyungpook National University, Daegu 41566, Korea.
² Food and Bio-Industry Research Institute, Inner Beauty/Antiaging Center, Kyungpook National University, Daegu 41566, Korea.
³ Department of Chemistry, Kyungpook National University, Daegu 41566, Korea.
⁴ Department of Chemistry, University of California, Riverside, CA 92521, USA.
⁵ Mass Spectrometry Converging Research Center and Green-Nano Materials Research Center, Daegu 41566, Korea.
⁶ knu BnC, Daegu 41566, Korea.

Abstract

The antioxidant effects of the ethyl acetate fraction of Dillenia indica bark (DIBEt) and the underlying mechanisms were investigated in tert-butyl hydroperoxide (t-BHP)-stimulated oxidative stress in RAW 264.7 cells. Paper spray ionization-mass spectroscopy with positive-ion mode tentatively revealed 27 secondary metabolites in D. indica bark extract; predominant among them were alkaloids, phenolic acids, and flavonoids. A new triterpenoid (nutriacholic acid) was confirmed in DIBEt for the first time. DIBEt had strong free radical-scavenging capabilities and was also able to reduce t-BHP-induced cellular reactive oxygen species (ROS) generation in RAW 264.7 cells. DIBEt was found to prevent oxidative stress by boosting the levels of heme oxygenase-1 (HO-1) through the up-regulation of nuclear factor erythroid 2-related factor 2 (Nrf2) via the regulation of extracellular signal-regulated kinase (ERK) phosphorylation in RAW 264.7 cells. These results support the potential of DIBEt for defense against oxidative stress-stimulated diseases.

Keywords: Dillenia indica; RAW 264.7 cells; antioxidant; heme oxygenase 1 (HO-1); nuclear factor erythroid 2-related factor 2 (Nrf2).

Grants and funding

2020R1A2C2011495/National Research Foundation of Korea