Thin-layer chromatography (TLC) method for qualitative analysis of food supplements, containing ginger (Zingiber officinale Roscoe.)

Abstract

Background: Ginger, Zingiber officinale Roscoe, has a long history of medicinal use, the rhizome is noted for the treatment of conditions, such as nausea or vomiting of motion sickness and pregnancyrelated nausea. [1,4] Ginger contains several principal substances which are mainly 6-gingerol and 6- shogaol, which are responsible for the biological activities of ginger. [1,3] The aim of this study is to make qualitative analysis of biologically active compounds in food supplements, containing ginger rhizome extract or powder. Materials and methods: Four different food supplements were bought from the community pharmacy in Lithuania. Samples preparation was carried out according to the scientific literature. [2] The thin-layer chromatography analysis was performed on silica gel 60 UV254 glass plates (E-Merck, Germany) using hexane:ether (40:60 v/v) as a mobile phase. [1,2] The individual standard’s solutions and food supplement’s samples application were performed using the CAMAG-Linomat V automated spray on band applicator. After development, the plates were air-dried, sprayed with a 10 mg/L detection solution of vanilin in sulfuric acid and examined in daylight while heated at 100-105 oC for 10 min. Images of the plates were captured at 366 nm and white light using the CAMAG TLC Scanner. [3,4] Results: The ginger standards were easily resolved in the TLC mobile phase. Under the chromatography conditions described, 6-gingerol and 6-shogaol which migrated further upstream, showed retention factors of 0,77 and 0,89, respectively. TLC fingerprints developed for the food supplements showed very similar retention factors to standard’s Rf values using both 366 nm and white light. The four samples which were run parallel to each other, showed similar chemical profiles with only slight variations in the intensities of the zones using two different scaning properties. Conclusions: The TLC method developed for quali[...].