Antioxidant and Anticancer Potentials and Metabolic Profiling of Benjakul, A Thai Herbal Preparation

Abstract

Benjakul (BJK), a Thai folk remedy has been used in traditional medicine for the treatment of various illnesses. This study aimed to assess  the antioxidant, and anticancer properties, and metabolic profile of Benjakul. The antioxidant activity of the ethanol extract of BJK and its component medicinal plants (Piper retrofractum Vahl., Piper sarmentosum Roxb., Piper interuptum Opiz., Plumbago indica L., and  Zingiber officinale Rosc.) was assessed using the Ferric Reducing Antioxidant Power (FRAP) assay, and 2,2-diphenyl-1-picrylhydrazyl  (DPPH) free radical scavenging assay. The anticancer activity was assessed through cytotoxic effect against cholangiocarcinoma (CCA)  (bile duct cancer) cell lines (KKU-213B and KKU-100) using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.  The metabolic fingerprint and potential bioactive compounds in the ethanol extract of BJK and component medicinal plants was  investigated using Nuclear Magnetic Resonance (NMR) spectroscopy. The FRAP and DPPH assays revealed that the ethanol extracts of BJK  and its component medicinal plants possessed antioxidant activity with Zingiber officinale exhibiting the highest activity. The FRAP  value and EC50 for DPPH radical scavenging activity for Zingiber officinale were 94.860 ± 0.156 µg AAE/mg extract and 86.63 g/mL,  respectively. The metabolic profiling identified vanillic acid and curcumin as the main bioactive metabolites in BJK and its component  medicinal plants. The partial least squares (PLS) loading plot revealed that the methoxy group is associated with the inhibition of CCA  cells, and phenolic hydroxyl protons as the potential pharmacophore of the bioactive molecules. Therefore, BJK could be considered as a  potentially effective treatment for bile duct cancer.