Ambrosia artemisiifolia L. is an allergen species that belongs to the group of invasive weeds, and is very frequent and present in our region. The use of essential oils in the control of weeds attracts great attention of researchers. Many of them have already pointed out the ability of some oils and/or their individual components to delay seed germination of various weeds or completely inhibit it. In this paper, we present results of the efficacy of three essential oils on A. artemisiifolia seeds; the trials were carried out using two different in vitro methods, in which the percentage of seed germination was measured 7th day.  In testings with seeds soaked in essential oil solution, in Petri dishes (500 ml in 100 ml of distilled water), a significant inhibition of germination was observed in the case A. graveolens and S. officinalis oil (100 % and 97 % , respectively), while the oil of S. montana demonstrated slightly weaker inhibitory effect (86 %). When essential oils were applied in form of a vapour (an oil droplet of 25 ml applied on the inner side od Petri dish lids), A. graveolens and S. officinalis oils inhibited the seed germination 100 % and and 95 % , respectively , while the oil of S. montana again demonstrated the weakest inhibitory effect (52 %).

The aim of the presented research was to determine whether the application of the essential oils of A. graveolens, S. officinalis and S. montana in form of a solution or vapor, affects, and to what extent they are important for germination of seeds of the weed species A. artemisiifolia L.

Traditional plant extraction methods commonly employ hazardous solvents that threaten human health. Considering these, the study sought to explore the efficacy of seven distinct types of apple cider vinegar (ACV) as an alternative solvent for isolating polyphenols from dry elderberries as a raw material. In the pursuit of identifying the most suitable solvent, a conventional solid-liquid extraction was executed, with a comparative assessment involving three different ethanol solution solvents (30%, 50%, and 70%, (v/v)). Subsequently, once the optimal solvent was determined, an ultrasound-assisted extraction was carried out. The optimization process encompassed a range of sonication amplitudes (20-100%) and extraction durations spanning from 120 to 360 s. The extracts’ characterization, including extraction yield and total phenolic content, was performed to ascertain the most favorable extraction parameters. The utilization of ACV in conjunction with a sonication amplitude of 100% and an extraction duration of 360 s yielded the highest TPC, amounting to 84.44 mg GAE/g dry extract (DE). In contrast, the lowest ethanol concentration (30%) produced the highest TPC, reaching 101.70 mg GAE/g DE when a sonication amplitude of 100% and an extraction time of 120 s were applied.

This study investigated solvent effects on the phytochemical composition of Quassia undulata leaves a medicinal plant used in treating arrays of diseases including fever and cough. The leaves were collected, washed, air-dried, pulverized and evaluated for some inherent phytochemicals using four different solvent systems based on their polarities. The solvents are methanol, acetone, ethyl acetate and chloroform. The methanol extract was found to have the highest number of secondary metabolites (saponins, tannins, flavonoids, steroids, coumarins, anthraquinones, alkaloids and phenols). None of the extracts tested positive for the presence of phlobatannins, terpenoids and emodins. The methanol extract was further analyzed quantitatively for some of the determined phytochemicals. Tannins had a concentration of 3.131 mg of catechin equivalents per 100 mg sample (mg CE/100g), alkaloids - 5.200 %, total phenolics - 11.828 mg of gallic acid equivalents per gram of extract (mg GAE/g), flavonoids - 8.074 mg of quercetin equivalents per gram of extract (mg QE/g) while 0.673 % saponins were detected. The presence of these secondary metabolites might justify the ethnomedicinal uses of Quassia undulata leaves as their bioactivity has been found to be dependent on the solvent used for extraction.