Identification of Ethyl Para-Methoxycinnamate and Kaempferol in the Ethanol Extract of <i>Kaempferia galanga </i>L. Rhizome as Biomaterial for Drug Candidate Using Spectrophotometric and Chromatographic Analysis

Abstract

Kaempferia galanga L. rhizome (KGR) has been used empirically in Asian countries, particularly Indonesia, to treat inflammation. Ethyl para-methoxycinnamate (EPMC) and kaempferol, two phytochemicals contained in KGR, are scientifically proven in playing a role as anti-inflammatory agents. Several studies have explored the pharmacology activities of EPMC and kaempferol, thus a further exploration of the physicochemical properties of the ethanol extract of KGR (EEKGR) is needed. This study aims to confirm the presence of EPMC and kaempferol in EEKGR using spectrophotometric and chromatographic analysis. The KGR was purchased from Buniayu Plantation in Subang, West Java, Indonesia and was identified at Herbarium Bandungense, School of Natural Science and Technology (SITH), Bandung, Indonesia. EEKGR was prepared by cold extraction technique 3x24 hours using 70% ethanol, then was rotary-evaporated to a viscous consistency. The yield of the extract produced was 14.55% w/w (72.7935 g viscous extract from 500 g dried powder of rhizome), with a water content of 4.37% (thermogravimetry method). Phytochemical screening revealed the presence of phenolics and flavonoids. Thin Layer Chromatography (TLC) indicated that EPMC might be present in the EEKGR (Rf = 0.92 compared to that of standard EPMC = 0.92), and kaempferol (Rf = 0.26 compared to that of standard kaempferol = 0.25). The spectrophotometric analysis of EEKGR confirmed the presence of benzoyl and cinnamoyl bands, which positively belongs to flavonoid (UV spectrum = 200-400 nm). The High-performance Liquid Chromatography (HPLC) analysis of EEKGR proved chromatogram peak at 7.2 min which is similar with the standard EPMC (detection was set at 308 nm), however, no chromatogram peak of kaempferol at 4.0 min was observed. Generally, these spectrophotometric and chromatographic analysis results proved that EPMC is present in fair amount in the EEKGR therefore, this extract is interesting to be developed as a biomaterial for drug candidate, particularly to treat inflammation.