The study of dependence of the prenyl flavonoids content in the hop dry extract on temperature parameters of its obtaining

Abstract

When developing the technology of a dry extract of hop cones as an active pharmaceutical ingredient with the estrogen-like action the key factors that can affect the quality of the finished product have been investigated. Taking into account that hop prenyl flavonoids are relatively unstable compounds and under certain thermodynamic conditions are prone to transformation the influence of the temperature parameters such as evaporation and drying of the hop liquid extract on the content of xanthohumol (X), isoxanthohumol (IX), xanthohumol, isoxanthohumol, 8-prenylnaringenin and 6-prenylnaringenin has been determined by HPLC in the samples of liquid and dry extracts. It has been found that sparing conditions of evaporation and drying used has led to decreasing the quantitative content of X, IX, 8-PN and 6-PN in the dry extract compared with the content of these compounds in the water-alcohol liquid extract in the range of 14, 16, 8, 14%, respectively. The use of plants containing phytoestrogens, with its historical length may be compared with the history of medicine in general. One of the most interesting sources of compounds with the estrogen-like action is a hop cones. The results of the pharmacological studies of hop extracts indicate the relationship between estrogenic activity of the objects and the fraction of prenyl flavonoids: xanthohumol (X), desmethylxanthohumol (DMX), isoxanthohumol (IX), 8-prenylnaringenin (8-PN) and 6-prenylnaringenin (6-PN). It has been found that the marked estrogenic activity of the polyphenolic fraction belongs to 8-PN and characterizes this compound as the most powerful pharmacological agent among the known phytoestrogens [7,8,10].The process chain for obtaining APIs of the plant origin consists of different sets of operations performed according to the specific technological modes. Based on thermolabile properties of most substances of the plant origin the development of the technology for obtaining the corresponding APIs requires the study of dependence of the composition at each process stage involving heating of the product.The aim was to study the influence of temperature parameters of evaporation and drying processes of the hop liquid extract on the content of xanthohumol, isoxanthohumol, 8-prenylnaringenin and 6-prenylnaringenin in the dry extract.The results obtained should become an important factor in development of technology for obtaining the hop dry extract enriched in prenyl flavonoids as the promising API. Experimental PartThe starting materials were hop cones of "Xantha" cultivar (the product of the Polissya Institute of Agriculture at the NAASU) harvested in 2012, n-hexane, ethanol and purified water. For cyclization of chalcones X and DMX to the corresponding flavanones IX, 8-PN and 6-PN the hop cones were pretreated by water steam for 1 hour. After thermal pretreatment the remaining moisture was removed from the raw material, and hop cones were extracted in two steps. All extraction steps were performed by the method of filtration extraction at the room ...