Development of the spectrophotometric method for the quantitative determination of phenolic compounds calculated with reference to 6-gingerol in tablets based on a dry ginger extract

Abstract

Zingiber officinale has a wide range of pharmacological properties, including hypoglycemic and antioxidant ones. Most literature sources associate the pharmacological activity and mechanism of action of ginger with the content of phenolic compounds, and in particular gingerol.

Aim. To develop the spectrophotometric method for the quantitative determination of the total amount of phenolic compounds calculated with reference to 6-gingerol in tablets based on a dry ginger extract.

Materials and methods. The study object were tablets with an average weight of 0.5 g containing 0.3 g of a dry ginger extract (manufacturer – “Medagroprom”, Dnipro) obtained by the direct compression method. The spectrophotometric method was used to determine phenolic compounds calculated with reference to 6-gingerol.

Results and discussion. The spectral characteristics of a standard sample of 6-gingerol, a predominant substance among biologically active phenolic compounds of ginger, have been studied. It has been shown that its absorption spectrum in the range from 220 to 400 nm contains one absorption band with a maximum at 281 nm, which can be used as an analytical absorption band for the quantitative determination by absorption spectrophotometry. It has been proven that excipients do not interfere with the quantitative determination of the total amount of phenolic compounds in the composition of tablets with a dry extract of ginger since they do not absorb electromagnetic radiation in the region of the analytical maximum. It has been found that the content of the total amount of phenolic compounds calculated with reference to 6-gingerol in the experimental batch of tablets is 0.03556 ± 0.0088 g/tab. The relative uncertainty of the mean determination was 1.007 %.

Conclusions. The spectrophotometric method for the quantitative determination of the total amount of phenolic compounds calculated with reference to 6-gingerol in tablets based on a dry ginger extract with the subsequent calculation by the standard method has been developed. It can be used to develop quality control procedures for the tablets under research.