Two highly invasive plant species, Lysimachia vulgaris and Lythrum salicaria are well-known for its anti-inflammatory, hemostatic, and antidiaroic activity. These plants are most widespread on the territory of Euroasia, where their traditional medicinal use has been reported. Due to their invasiveness, they are undesirable plants in  other parts of the world. Till this day, many studies were conducted regarding the biological and pharmacological activity of L. salicaria. In this study, the polyphenol content of plant extracts was examined using the Folin-Ciocalteou method. Antioxidant activity of selected plant species was also determined, using DPPH and FRAP methods. Extracts of different polarities were prepared using methanol, water, and acetone. Extraction was performed by maceration and ultrasonic extraction. The results of the study show that both plant species possess antioxidant activity. Lythrum salicaria extracts show a significant polyphenol content and antioxidant capacity, with results notably higher than the results of studies conducted so far. The different antioxidant activity of the prepared extracts confirms the influence of solvents and extraction methods on the utilization of the antioxidant potential of plants. Additionally, for the aqueous extracts prepared by ultrasonic extraction method, an in vitro study of antibacterial activity was conducted. Both plant species show antibacterial activity, with an emphasis on the very strong antibacterial activity of L. salicaria extracts against selected bacterial strains.

Capsella bursa-pastoris (L.) Medik. (known as shepherd's purse) is a plant whose parts are used as medicine in herbal medicine. It is applicable as a medicine in the treatment of all forms of internal bleeding, for the treatment of hemorrhoids, excessive menstruation, but also for the usual stopping of nosebleeds. Through this research, the influence of organic solvents and their aqueous mixtures on the efficiency of polyphenol extraction and antioxidant activity was compared. The inhibition of free radicals was tested by the DPPH method, while the FRAP method was used to test the reduction potential. Analyzes have shown that water is the most effective solvent in the isolation of polyphenols from the aerial parts of shepherd's purse. Mixtures of organic solvents with water also showed high efficiency in the extraction of bioactive components, while the weakest results were obtained for extracts prepared in pure organic solvents.

Aims: The aims of the study were to analyse the polyphenols of Pulicaria dysenterica (L.) Bernh. methanolic extracts from aerial and underground parts, assessment of antioxidant activity and to evaluate their cytotoxicity on HeLa cells of cervical cancer. Methodology: The total phenolic content (TPC) of extracts was determined by the Folin-Ciocalteu spectrophotometric method. The qualitative and quantitative analysis of individual polyphenolic compounds were performed by the reverse phase HPLC method. The antioxidant capacity was evaluated by both, 2,2-diphenyl1-picrylhydrazyl radical and FRAP assay, while cytotoxicity of the extracts was assessed by MTT assay. Results: TPC of the samples were 127.62±2.22 and 244.12±8.84 mg gallic acid equivalent/g extract. In the extracts chlorogenic acid in amount of 10.06±0.96 and 11.32±0.28 mg/g, flavonoid rutin in amount of 5.68±0.13 mg/g and three caffeic acid derivatives were recorded. Extract from underground parts achieved better antioxidant activity with IC50 value 55.36±0.75 µg/mL and FRAP value 2411.12±37.22 µmol Fe2+g-1 compared to the one from aerial parts. Extract from aerial parts achieved better cytotoxic activity with 50% inhibition of viability (IC50) at concentration of 0.389±0.07 mg/mL, against HeLa cells, compared to the extract from underground parts. Conclusion: Analyzed Pulicaria dysenterica extracts contained phenolic acids and flavonoids. The extracts showed good antioxidant activity and cytotoxic properties against HeLa cells in vitro.

In this paper, three complexes with 8-hydroxyquinoline (8-HQ) were synthesized, their spectral analysis was performed and the antimicrobial effect was examined in vitro. The stoichiometric ratio of the complex was determined conductometrically and spectrophotometrically. FTIR and UV/VIS spectroscopy were used for structural characterization. Antimicrobial activity was examined by diffusion technique on selected gram-positive and gram-negative bacteria, and C. albicans. Square planar and octahedral geometry complexes were synthesized by mixing in a molar ratio of 1:2 (M:L). Based on the spectral data, it is concluded that both oxygen and nitrogen atoms from 8-HQ are involved in the formation of the complex. The antimicrobial activity of the complexes is high, with zones of inhibition in the range of 15 - 28 mm. 8-HQ was shown to have a significantly higher ability to inhibit the growth of the tested microorganisms.