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The influence of low-intensity electromagnetic radiation (EMR) on the content of phenolic compounds (PC) in plants on different stages of ontogeny is discussed. A medicinal plant (Calendula officinalis L.) and agricultural crop Fagopyrum sagittatum G., diploid varieties and tetraploid varieties were chosen as objects of study. Microwave EMR in two frequency bands, 53.57-78.33 GHz (wide range mode) and 64.00-66.00 GHz (narrow range mode), has been selected to learn the physical effects on seeds, with a treatment exposure time of 20, 12, or 8 min. The experiments were conducted under laboratory and field conditions. Treated and control seeds were germinated by 100 pcs in a growth chamber on moistened filter paper at 22–24˚C in the dark and placed on the daylight from the third day. The level of PC in the seedlings was measured with the Folin-Ciocalteu reagent. It was found that in the EMR pretreated C. officinalis seedlings the level of PC is maximal on 14th day of germination. The wide mode treatment for 12 min results in a two-fold increase in the level of PC in juvenile shoots with respect to control. Different constitutional levels of phenolic compounds in the leaves of diploid and tetraploid varieties of F. sagittatum in the most critical phases of ontogeny were found. It is recommended to use EMR with a 12 min exposure time for C. officinalis. The narrow frequency mode with an exposure time of 20 min is preferable to use for most varieties of F. sagittatum., Theinfluence of low-intensity electromagnetic radiation (EMR) on the content ofphenolic compounds (PC) in plants on different stages of ontogeny is discussed.A medicinal plant (Calendula officinalis L.) and agricultural crop Fagopyrumsagittatum G., diploid varieties and tetraploid varieties were chosen as objects of study. MicrowaveEMR in two frequency bands, 53.57-78.33 GHz (wide range mode) and 64.00-66.00GHz (narrow range mode), has been selected to learn the physical effects onseeds, with a treatment exposure time of 20, 12, or 8 min. The experiments wereconducted under laboratory and field conditions. Treated and control seeds weregerminated by 100 pcs in a growth chamber on moistened filter paper at 22–24˚Cin the dark and placed on the daylight from the third day. The level of PC inthe seedlings was measured with the Folin-Ciocalteu reagent. It was found thatin the EMR pretreated C. officinalis seedlings the level of PC is maximal on14th day of germination. The wide mode treatment for 12 min results in atwo-fold increase in the level of PC in juvenile shoots with respect tocontrol. Different constitutional levels of phenolic compounds in the leaves ofdiploid and tetraploid varieties of F. sagittatum in the most critical phasesof ontogeny were found. It is recommended to use EMR with a 12 min exposuretime for C. officinalis. The narrow frequency mode with an exposure time of 20 minis preferable to use for most varieties of F. sagittatum.

Antiradicalactivity of essential oils of korean mint (Agastacherugosa (Fisch. et Mey)), blue giant hyssop (Agastache foeniculum (Pursh) Kuntze),hyssop (Hyssopus officinalis L.),lavander (Lavandula angustifolia L.),peppermint (Mentha piperita L.),lemon mint (Mentha piperita var. citrata (Ehrh.) Briq), monarda (Monarda fistulosa L.), oregano (Origanum vulgare L.), common sage (Salvia officinalis L.), clary (Salvia sclarea L.), and winter savory (Satureja montana L.) cultivated in theCentral Botanical Garden of NAS of Belarus was investigated in the reactionwith the cation-radicals of 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonicacid) (ABTS+·).The most pronounced antiradical activity was observed for the essential oilswith a high content of phenolic compounds: winter savory and monarda.Antiradical properties of the essential oils and individual phenolic andterpene compounds (eugenol, carvacrol, thymol, citral, (+)-pulegone) in thereaction with ABTS+·significantly differ in aqueous solutions and ethanol-water mixtures.Нigh antibacterial activity of selected components of essential oils fromthe Lamiaceae plants, carvacrol,citral, and linalool, towards test organisms Sarcina lutea, Esherichia coli, Staphylococcus saprophyticus,Pseudomonas fluorescens, Bacillus megaterium, Pseudomonas putida was shown.The antibacterial activity of enantiomers of pinene and limonene wasdetermined. The dextrorotary isomer of α-pinene possesses a significantlyhigher level of activity as compared with the levorotary one. S-(-)-limoneneproves itself as a more active antimicrobial component towards Sarcina lutea and Staphylococcus saprophyticus than R-(+)-limonene. Both enantiomersshow comparable activity towards Esherichiacoli. Due to the high antibacterial activity the essential oils from Satureja montana and Monarda fistulosa can be considered aseffective antibacterial agents., Antiradical activity of essential oils of korean mint (Agastache rugosa (Fisch. et Mey)), blue giant hyssop (Agastache foeniculum (Pursh) Kuntze), hyssop (Hyssopus officinalis L.), lavander (Lavandula angustifolia L.), peppermint (Mentha piperita L.), lemon mint (Mentha piperita var. citrata (Ehrh.) Briq), monarda (Monarda fistulosa L.), oregano (Origanum vulgare L.), common sage (Salvia officinalis L.), clary (Salvia sclarea L.), and winter savory (Satureja montana L.) cultivated in the Central Botanical Garden of NAS of Belarus was investigated in the reaction with the cation-radicals of 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS+·). The most pronounced antiradical activity was observed for the essential oils with a high content of phenolic compounds: winter savory and monarda. Antiradical properties of the essential oils and individual phenolic and terpene compounds (eugenol, carvacrol, thymol, citral, (+)-pulegone) in the reaction with ABTS+· significantly differ in aqueous solutions and ethanol-water mixtures.Нigh antibacterial activity of selected components of essential oils from the Lamiaceae plants, carvacrol, citral, and linalool, towards test organisms Sarcina lutea, Esherichia coli, Staphylococcus saprophyticus, Pseudomonas fluorescens, Bacillus megaterium, Pseudomonas putida was shown. The antibacterial activity of enantiomers of pinene and limonene was determined. The dextrorotary isomer of α-pinene possesses a significantly higher level of activity as compared with the levorotary one. S-(-)-limonene proves itself as a more active antimicrobial component towards Sarcina lutea and Staphylococcus saprophyticus than R-(+)-limonene. Both enantiomers show comparable activity towards Esherichia coli. Due to the high antibacterial activity the essential oils from Satureja montana and Monarda fistulosa can be considered as effective antibacterial agents.

The essential oils from Korean mint (Agastache rugosa (Fisch. et Mey)) and Lemon mint (Mentha piperita var. citrata (Ehrh.) Briq.) have a high content of chiral terpene compounds that reaches 16.1 % and 10.5 % accordingly with the predominance of limonene, while the oils are obtained from preliminary dried plant material. The content of the enantiomers in peppermint (Mentha x piperita L) oil does not exceed 3.8 %. In each of three investigated Lamiacea species, one specific enantiomeric form of α-pinene, β-pinene, and limonene prevails during all vegetation period; the differences in accumulation of these three monoterpene enantiomers in essential oils obtained from the plants on different ontogenetic stages and after different preprocessing history (fresh and dried material) are discussed for the first time. (-)-α-Pinene was found as the dominating form in the essential oils from all investigated species. (-)-β-Pinene and (+)-limonene with a 86-100 % enantiomeric excess were detected in the oil...