###### Abstract  
An acetonic and  
plants [8]. To achieve the goals set, it is necessary to improve disease prevention and husbandry practices [7; 8; 9]. Alternative treatments and prophylactic measures have been suggested and used in conventional and organic farms [5; 8; 10]. As alternative therapy or co-combined with standard treatment, medicinal plants have a promising place in battling infections [5; 10; 11]. Although herbal medicine for the treatment and prevention of bovine mastitis has been in use for decades [11], research reports are lacking [8; 12]. Additionally, _Tanacentum vulgare_ has not been reported as an antibacterial agent against bovine mastitis and has only been mentioned once in ethnoveterinary studies previously [9]. _Tanacentum vulgare_ _syn. Chrysanthemum vulgare_ _L., commonly known as Tansy (Common Tansy, Garden Tansy, Golden Buttons), is a perennial plant that belongs to the _Asteraceae_ family. It has two varieties: _var. vulgare_ which grows in Europe and North America, and _var. boreale_ which is more typical to Russia and Asia. Typically, _T. vulgare_ is found in meadows, along roads, and in hedges and wasstelands [13; 14]. _T. vulgare_ is an aromatic herbaceous plant with a yellow inflorescence and deep green pinnatipartite to pinnatisect leaves [13]. The chemical composition of _T. vulgare_ varies due to its high environmental adaptability [13; 15; 16]. Studies of _T. vulgare_ provide information about the chemical composition and the properties of its aerial parts (flower, leaf, herb) and underground organ (root). Although secondary metabolite groups are similar, individual chemical compounds in the aerial parts of the plant differ. The aerial parts of _T. vulgare_ contain essential oil, nonvolatile sesquiterpenes, polyphenic compounds, phenolic acids, fatty acids, sugars, vitamins, and minerals [14; 16; 17; 18; 19]. Traditional uses of _T. vulgare_ include anthelmintic effects, treatment of headaches, neuralgias, anorexia, respiratory infection, and rheumatats, and some cultures have used it as an abortificient [20; 21]. Considering that _T. vulgare_ essential oil contains toxic compounds such as thujones, it should be used with caution or externally [22]. In addition, people sensitive to the _Asteraceae_ family experience allergic contact dermatitis to _T. vulgare_ pollen [20]. _T. vulgare_ has potential activity against _herpes simplex_[23]. Most of the studies focus on the antioxidant, anti-inflammatory, and antimicrobial effects of _T. vulgare_, which are thought to be linked to essential oil and phenolic compounds found in the plant [19; 22; 24]. Therefore, the pharmacological properties and medicinal use of _T. vulgare_ plants vary depending on the part of the plant used and the extraction methods applied. Extraction methods, solvent, plant material-to-solvent ratio, time, pH, and temperature can influence the outcome of the extraction. More polar solvents generally lead to a higher yield of phenolic compounds [25]. The use of solvents of varying polarities leads to differing chemical compounds that are extracted from the same plant material. The highest rosmarinic acid yield was extracted by 50% methanol, but 70% acetone extracted a high yield of 3'-hydroxy-5,6,7,4'-tetramethoxyflavone. However, chloroform extraction provided the highest amounts of sinensis and eupatorin [26]. Additionally, the concentration of solvent can change the outcome of extract yield and composition, as well as the properties of the extract. The highest antioxidant activity and polyphenol content was observed in 100% ethanol extracts, but the highest extraction yield was from 50% acetone [27]. To assess the effects of the crude extracts of _T. vulgare_ flowers and leaves, we aimed to compare two types of solvents with varied concentrations. The total phenolic content was determined, and Fourier transform infrared spectroscopy was used to characterize the chemical composition of the extracts. This study was aimed to determine the in vitro antimicrobial properties of different _T.