Salinity Treatments Promote the Accumulations of Momilactones and Phenolic Compounds in Germinated Brown Rice

Mehedi Hasan; Nguyen Van Quan; La Hoang Anh; Tran Dang Khanh; Tran Dang Xuan

doi:10.3390/foods12132501

Salinity Treatments Promote the Accumulations of Momilactones and Phenolic Compounds in Germinated Brown Rice

Foods. 2023 Jun 27;12(13):2501. doi: 10.3390/foods12132501.

Authors

Mehedi Hasan¹, Nguyen Van Quan¹, La Hoang Anh^{1

2}, Tran Dang Khanh^{3

4}, Tran Dang Xuan^{1

2}

Affiliations

¹ Graduate School of Advanced Science and Engineering, Hiroshima University, 1-5-1 Kagamiyama, Higashi-Hiroshima 739-8529, Japan.
² Center for the Planetary Health and Innovation Science (PHIS), The IDEC Institute, Hiroshima University, 1-5-1 Kagamiyama, Higashi-Hiroshima 739-8529, Japan.
³ Agricultural Genetics Institute, Pham Van Dong Street, Hanoi 122000, Vietnam.
⁴ Center for Agricultural Innovation, Vietnam National University of Agriculture, Hanoi 131000, Vietnam.

Abstract

This is the first investigation, conducted in a completely randomized design (CRD), to determine the effects of different salinity levels (75 and 150 mM) and germination periods (3, 4, and 5 days) on momilactone and phenolic accumulations in germinated brown rice (GBR) var. Koshihikari. Particularly, the identification of bioactive compounds was confirmed using electrospray ionization-mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) spectroscopy (¹H and ¹³C). Momilactone A (MA) and momilactone B (MB) amounts were determined by ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS), whereas other compounds were quantified by spectrophotometry and high-performance liquid chromatography (HPLC). Accordingly, GBR under B2 treatment (75 mM salinity for 4 days) showed the greatest total phenolic and flavonoid contents (14.50 mg gallic acid and 11.06 mg rutin equivalents, respectively, per g dry weight). GBR treated with B2 also accumulated the highest quantities of MA, MB, ρ-coumaric, ferulic, cinnamic, salicylic acids, and tricin (18.94, 41.00, 93.77, 139.03, 46.05, 596.26, and 107.63 µg/g DW, respectively), which were consistent with the strongest antiradical activities in DPPH and ABTS assays (IC₅₀ = 1.58 and 1.78 mg/mL, respectively). These findings have implications for promoting the value of GBR consumption and rice-based products that benefit human health.

Keywords: antioxidants; bioactive compounds; germinated brown rice; momilactones; phenolics; salinity.

Grants and funding

This research received no external funding.