Comparison of Chemical Composition and Antioxidant Activity of Extracted Zingiberaceae Rhizome using Subcritical Water Extraction

In Malaysia, many local herbs can take advantage of their benefit for health products, cosmetics, and food production. In this research, fresh Zingiberacea rhizomes including Curcuma Longa, Curcuma Zedoaria, Curcuma Xanthorrhiza, Zingiber Officinale, and Zingiber Zerumbet rhizomes were extracted using the subcritical water extraction (SWE) unit located at AM Zaideen Ventures Sdn Bhd in Kuala Lumpur (Malaysia). The focus of this research is to analyze the freeze-dried powder extracts from the fresh Zingiberaceae rhizome for the phytochemical screening and bioactive compounds. Operating parameter used in the extraction process was fixed at temperature of 110°C, pressure at 10 bar and extraction time of 15 minutes. The freeze-dried powder extracts were screened for its phytochemicals inclusive alkaloids, steroids, terpenoids, glycosides, tannin and saponin. For bioactive compounds analysis, extracts were evaluated for Total Phenolic Content, Total Flavonoid Content, DPPH scavenging activity assay, and bioactive compound using Gas-Chromatography Mass Spectrophotometry analysis. The results show that there was a different presence of phytochemicals compounds in different Zingiberaceae extracts. At 10mg/ml concentration of powder extract, Zingiberaceae rhizomes showed variations in total phenol and flavonoid content, ranging from 134.65 to 285.19 mg GAE/g and from 22.58 to 181.62 mg QE/g, respectively. For DPPH radical scavenging activity, observed at 10mg/ml of freeze-dried extract, all Zingiberacea demonstrated significance antioxidant activity of more than 85% inhibition. Bioactive compounds detected in Zingiberaceae rhizomes shows significance quality. This finding supports the exploration of indigenous herbs market in Malaysia and the potential of water-based extracts on fresh Zingiberaceae rhizomes.