Optimization of extraction methods for total polyphenolic compounds obtained from rhizomes of Zingiber officinale

In an alternative medicine, aqueous extracts and decoctions of a ginger root (Ginger –Zingiber officinale Roscoe L., Ginger family – Zingiber aceae) are used as antibacterial, diaphoretic, analgesic, anti-emetic, anti-inflammatory drugs. The aim of our study was to determine the optimal technological conditions of total polyphenolic compounds extraction under different extraction conditions from ginger roots. Ethanol extracts of the plant were obtained by maceration method, Soxleted apparatus and ultrasonic method. Polyphenol compounds and flavonoids were determined with the standard spectrophotometric methods using the Folin-Ciocalteu and differential spectrophotometry (complexation with AlCl3), respectively. It was found that the highest content of polyphenolic compounds and flavonoids from the raw material into the solvent system are determined after sonication followed by subsequent maceration during 10 (total polyphenolic compounds) and 7 days (flavonoids). Their concentration was 2.48 ± 0,029% and 1.3±0,08 %, respectively.