Phytochemical and Antioxidant Characterization of Zingiber zerumbet Radix (Lempuyang Root)” which is part of the “SARS-CoV-2 inhibition using flavonoid compounds

Abstract

Corona Virus Disease 201 (CoViD-19) is a global disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) since 2019. Several studies have indicated the importance of several flavonoids in inhibiting SARS-CoV-2 M pro such as catechin, epigallocatechin, kaempferol, naringenin, quercetin. Zingiber zerumbet contains flavonoid which may be potential to inhibit SARS-CoV-2, however, deep knowledge of Zingiber zerumbet is not completely known and further knowledge on its effectiveness towards COVID-19 remains unknown. Hence, extract phytochemical screening, phenolic content, flavonoid content, and antioxidant activity determination was done to detect and quantify the phytochemicals available. The extraction was done with maceration three times and solvent of 96% ethanol, followed by phytochemical screening, DPPH, ABTS, and FRAP assays. Zingiber zerumbet yield extract in this research was 16.52% w/w. The phytochemical screening resulted in the presence of alkaloid, quinone, steroid, flavonoid, and tannin. The total phenolic content found was 3.83 mg GAE/g of extract, and the total flavonoid content found was 2.66 ± 0.0054 mg QE/g of extract. The IC50 calculated from DPPH was 5660 ± 805.7 ppm, the IC50 calculated from ABTS was 527.4 ppm. On the other hand, FRAP resulted in 181.9721 ± 1.1331 mg TE/gram of extract. Zingiber zerumbet radix had lower antioxidant activity in both DPPH and ABTS as the IC50 value of ascorbic acid and Trolox standard are 35.42 ± 0.7258 and 55.34 ± 1.377 ppm, respectively.