Isolation, characterization and pharmacological application of bioactive compound from leaves of Alpinia nigra (Gaertn.) B.L. Burtt

Abstract

The present study is focused on investigating the potential uses of the herbaceous plant Alpinia nigra (Gaertn.) B.L. Burtt (Zingiberaceae). Traditionally this plant is used in folk remedies for curing gastritis and infectious diseases. The plant leaves are used as a food-flavoring agent by tribal people in Northeast (NE) India. However, the scientific community has not explored the plant leaf for its medicinal properties. Thus in the present study, the leaf extracts hexane (L-Hex), ethyl acetate (L-EtAc), and methanol (L-Met) were subjected to phytochemical analysis. The antibacterial, anti-biofilm, and anti-quorum sensing activities of the L-EtAc extract was determined by in-vitro analysis and was found to be potential. Further, the compound 3, 5-dihydroxy 4′,7-dimethoxy flavone (DHDM) was purified from L-EtAc, crystallized, and structural characterization was performed using multispectroscopic techniques including HRMS, FTIR, Raman, SC-XRD, 1-D NMR, and 2-D NMR. The cell viability assay showed no inhibition of DHDM at ≤200 μM concentration in THP-1 (human macrophage) and ≤80 μM in HaCaT (human keratinocyte) cell lines. Additionally, strong antioxidant properties and reduced ROS