Quantitative analysis of total phenolic and flavonoid compounds in different extracts from ginger plant (Zingiber officinale) and evaluation of their anticancer effect against colorectal cancer cell lines

Objectives: To quantify quercetin, gallic acid, rutin, naringin, and caffeic acid in the rhizome of Zingiber officinale different extracts in seven different solvents (methanol, ethanol, ethyl acetate, water, dichloromethane, chloroform, and n-hexane), for the first time, using HPLC/UV. Also, to study the anticancer activity of Zingiber officinale different extracts by evaluating its in vitro toxicity on HT-29 colorectal cancer cell line.

Methods: The fresh and dried rhizomes were extracted using Soxhlet (SOX) and maceration (MAC) methods. Separation of compounds was conducted using HPLC. The cell line used for MTT cell proliferation assay antiproliferative; is HT-29 (HTB-38) colorectal adenocarcinoma.

Results: The MTT test indicated that powder ginger extracted by MAC or SOX showed high cytotoxicity activity (IC₅₀<50) against HT-29 cells, except water using SOX, which showed mild cytotoxicity activity. The fresh ginger extracted by MAC using dichloromethane and those extracted by SOX using ethyl acetate showed strong cytotoxicity activity (IC₅₀ <50).

Conclusion: The phenolic and flavonoid contents of ginger can vary depending on the different extracts from ginger plant. Also, HPLC results revealed that quercetin was the highest in all extracts.