@Article{faf2636, 
author="An, An and Amanah, a Widya Nur and Aminah, Nanik Siti and Hafez-Ghoran, Salar Hafez and Abdjan, Muhammad Ikhlas and Kristanti, Alfinda Novi and Siswanto, Imam and Thant, Tin Myo and Manuhara, Y. Sri Wulan and Wibowo, Anjar Tri and Sugiharto, Sugiharto and Hariyanto, Geraldo Figo and Ramach, Muggundha Raoov and ran, ran and Takaya, Yoshiaki", 
title="Isoplanchol A, a New Phenolic Stereoisomer from Uncaria Gambir Sap with Antioxidant and Predicted Cyclin-Dependent Kinase 1 Binding Potential", 
journal="ES Food and Agroforestry", 
year="", 
volume="", 
pages="", 
abstract="Phenolic compounds of Uncaria gambir Roxb. are known for their antioxidant properties. The methanolic extract of gambir sap yielded the known planchol A (1) and a new stereoisomer, isoplanchol A (2), whose structures were elucidated by Ultraviolet–visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FT-IR), One-dimensional nuclear magnetic resonance/ Two-dimensional nuclear magnetic resonance (1D/2D NMR), and Direct analysis in real time–high-resolution mass spectrometry (DART-HRMS). In the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay, Half-maximal inhibitory concentration (IC50) values were 91.86 ± 0.50 µg/mL for the extract, 162.11 ± 1.65 µg/mL for 1, and 89.67 ± 0.74 µg/mL for 2. In the 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, IC50 values were 79.76 ± 0.36 µg/mL for the extract, 14.53 ± 0.21 µg/mL for 1, and 20.22 ± 0.50 µg/mL for 2, comparable to catechin (17.02 ± 0.08 µg/mL); the isomers’ order was reversed relative to DPPH, indicating assay-dependent activity. Density functional theory calculations gave similar Highest occupied molecular orbital-Lowest unoccupied molecular orbital (HOMO-LUMO) gaps (5.73–5.85 eV) for both. Molecular docking and 300 ns molecular dynamics simulations predicted stable binding of both compounds in the Adenosine triphosphate (ATP)-binding pocket of cyclin-dependent kinase 1 (CDK1), with a more favorable Molecular mechanics-Generalized born surface area (MM-GBSA) binding free energy for 2 (ΔGbind = –29.95 kcal/mol) than for 1 (–26.44 kcal/mol). These in silico results are hypothesis-generating and require experimental validation. Gambir sap is a source of antioxidant phenolics, and isoplanchol A (2) is a candidate for further biological investigation.", 
issn="2576-9898", 
doi="10.30919/faf2636", 
url="http://dx.doi.org/10.30919/faf2636" 
}