Medicinal plants contain various biologically active substances. This study aimed to investigate properties of plant extracts and component composition of plant raw materials from the continental part Kaliningrad region (Guards district). For this, we used column chromatography and IR spectroscopy.
The objects of the study were samples of plant extracts of Eryngium maritimum, Hedysarum neglectum, Melilotus officinalis, and Aesculus hippocastanum. To produce medicinal plant extracts, we prepared methanol extraction by the Soxhlet method for 8 h (15 cycles). The antioxidant activity of the studied samples was determined by their ability to reduce the radical 2,2-diphenyl-1-picrylhydrazyl. The disk-diffusion method was used to evaluate the antimicrobial activity of the plant extracts against such test strains as Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans.
In the extracts, 3,4-dihydroxybenzoic acid, astragalin, luteolin-7-glucoside, rosmarinic acid, and chlorogenic acid were identified. However, more research is needed to determine which of the individual phenolic compounds in E. maritimum, H. neglectum, M. officinalis, and A. hippocastanum are involved in exhibiting antioxidant activity. It was found that the plant extract of H. neglectum had activity against the bacterium B. subtilis and the mold fungus C. albicans, while the plant extract of E. maritimum was detrimental to the growth and development of both Gram-positive and Gram-negative bacteria.
Infrared spectroscopy can help in further studies to determine properties of medicinal plants to ensure the safety and efficacy of plant-based products.