Phytochemical composition of Humulus Lupulus L. in ontogeny under different treatments

Abstract

Wild hop (Humulus lupulus L.) is a double-headed perennial climbing plant that belongs to the Cannabaceae family. Hops contain many biologically active compounds possessing powerful antimicrobial, antioxidant and antifungal activity, due to which its original use was for medicinal purposes and only later began to be used in beer production. The aim of the work was to identify the effects of growth regulators (hibbersib and epin-extra) and biofertilizer (powder) on the content of soluble phenolic compounds, flavonoids, tannins, carotenoids, vitamins C and B, protein and sugars in plants of common hop (Humulus lupulus L.) during ontogenesis. Root cuttings of hops were planted in the beginning of May 2022 in protected ground under laboratory conditions. In the second variant rootstock were potted in soil with 10 g/kg powders; in the third variant rootstocks were treated with hibbersib (666.6 µg/l) by spraying; in the fourth variant also, rootstocks were treated with epin-extra (500 µl/l) by spraying. After 4 weeks, all variants were transplanted to the open field. The samples for analysis (leaves) were taken 4, 8, 12 and 16 weeks after planting in the open ground, the average night temperatures were +160C, +240C, +140C and +70C, respectively. Phytochemical composition of leaves was determined by spectrophotometric method. In control plants the content of phenolic compounds and vitamin C reached the highest values in the twelfth week after planting. The synthetic growth regulators (epin-extra and hibbersib) and the biofertilizer (pudrete) were shown to change the phytochemical composition of the hop plants to different extents. Powdertet increased the vitamin and protein content to a greater extent whereas growth regulators increased the content of phenolic compounds and sugars, particularly under the influence of hibbersib.