Background: Starting from the idea that unexplored areas may yield new and different ethnobotanical information, we performed a survey of traditional uses of plants in two neighboring districts situated in east Serbia (Bor and Aleksinac), both lacking in previous ethnobotanical reports, but characterized by an interesting history and culture, together with some specific features. In this study, we hypothesized that such small and specific areas could be of high ethnobotanical importance.Methods: Semi-structured interviews were used with 155 informants. Relative cultural importance (RCI) indices, such as the frequency of citation (FC), relative frequency of citation (RFC), relative importance index (RI), informant consensus factor (ICF-FIC), use value (UV), fidelity level (FL) and Jaccard index (JI), were calculated, and principal coordinate analysis (PCoA) was performed.Results: In this study, 2333 use-reports and 114 plants were recorded. Of the 101 medical herbs, 33 are included in the European Pharmacopoeia Edition 8.0. The most frequently used mode of preparation was as an infusion (50.0%), while leaf (44.7%) was the most used plant part. The highest FC and RFC values were recorded forHypericum perforatumL. (13.1 and 0.2, respectively), while the highest RI was documented forUrtica dioicaL. (1.0). ICF and FL indices showed important differences among selected groups of informants. The PCoA showed three homogeneous plant groups. Plants were mostly used for the treatment of digestive (49.1%), circulatory (41.2%) and respiratory system disorders (35.1%). Thirty-seven (32.5%) herbs were used for human nutrition, 14 (12.3%) in veterinary medicine, 17 (14.9%) in rituals and ethnoculture, while 24 (21.0%) for miscellaneous purposes. The highest degree of similarity was determined with studies conducted in close proximity. Four species are new to Balkan ethnobotany. New uses for some well-known plants are highlighted.Conclusion: The study indicated that small and specific areas in the Balkans may be an important reservoir of ethnobotanical knowledge.

The composition of essential oil from aerial parts of Ambrosia artemisiifolia L. from Bor (Serbia) was analyzed. The essential oil was obtained by hydrodistillation and analyzed by gas chromatography (GC-FID, GC-MS). In total, 45 compounds were detected (98.49% of the total). The essential oil was dominated by monoterpene (45%) and sesquiterpene (38.51%) hydrocarbons. The principal constituents were germacrene D (25.3%), limonene (21.6%), and α-pinene (15.7%). The microdilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the essential oil against five Gram-negative phytopathogenic strains. Essential oil exhibited strong antimicrobial activity against two Xanthomonas campestris strains and one referent and one natural isolate of Ervinia amylovora, causative agents of black rot and fire blight.

In this study an ethnobotanical survey was conducted in western Serbia (Mt. Tara) with the aim of collecting and preserving the traditional botanical knowledge. A group of local inhabitants (56) was interviewed using semi-structured questionnaires. The Relative Frequency of Citation (RFC) and Jaccard Index (JI) were calculated. There are 78 wild plant species recorded. The reported plant species belong to 34 families, where the families Rosaceae (41.18%), Asteraceae (23.53%) and Lamiaceae (20.59%) were dominant. Out of 78 documented plants, 70 plants (89.74%) are used in folk medicine, 42 (53.85%) in human nutrition, 22 (28.20%) in animal nutrition, 14 (17.95%) plants are used for miscellaneous purposes, while two plants (2.56%) are used in ethnoveterinary medicine. The highest RFC was recorded for Vaccinium myrtillus (0.38), followed by Urtica dioica (0.34), and Hypericum perforatum (0.25) and Fragaria vesca (0.25). The most frequently used mode of preparation was as an infusion (70.51%), while the most used plant part was the leaf (56.41%) followed by the flower/inflorescences (37.18%) and aboveground parts (28.21%). The highest degree of similarity was determined with studies conducted in close proximity (Mt. Zlatibor, JI 33.04). Local recipes and new usage of some well-known traditional plants in Serbia and the Balkans were documented.

The essential oil composition of fresh flowering heads (capitula) and fresh aerial parts of Centaurea finazzeri Adamović and Centaurea rupestris L. (Asteraceae, Centaurea sect. Acrocentron) from Štip, North Macedonia were analyzed. The essential oils were obtained by simultaneous distillation and extraction using Likens–Nickerson type apparatus and analyzed by GC-FID/GC-MS. In total, 112 compounds were identified representing 97.0–99.2% of the total oil composition. All samples were dominated by aliphatic hydrocarbons (46.3–85.7%). The dominant compounds differed between species. The most abundant compounds of C. rupestris essential oils were hexanal (10.7%, 6.3%) for aerial parts and flowering heads, respectively, (2E)-hexanal (10.6%) and α-pinene (6.0%) for aerial parts, and hexadecanoic acid (7.2%) and 2-methyl hexyl ester butanoic acid (4.5%) for flowering heads. The main volatile constituents of C. finazzeri oils were acetophenone (13.5%), (2E)-hexanal (12.1%), and hexadecanoic acid (6.9%) for aerial parts, and hexadecanoic acid (21,8%), heptacosane (10.3%), and nonacosane (9.1%) for flowering heads. Taxonomic implications are discussed.

Xanthium spinosum is a cosmopolitan annual herb used in traditional medicine worldwide. Although known from ethnobotanical studies, the species is scarcely investigated from the aspects of phytochemistry and biological activity. Therefore, the phenolic composition and biological activity of X. spinosum were examined. Plant specialised metabolites (phenolics) extracted from the roots, leaves and fruits with dichloromethane:methanol (1:1) were analysed by liquid chromatography mass spectrometry (LC-MS). In total 10 phenolic compounds were identified and quantified. Six compounds were common to all the extracts. Chlorogenic acid was the most abundant constituent in all the extracts (4.262 mg/g in the fruit extract, 0.820 mg/g in the leaf extract, and 0.540 mg/g in the root extract). The biological activity (antimicrobial and antibiofilm) of the extracts was tested against 12 microfungi and 12 bacterial strains by the microdilution method. All the extracts exhibited moderate antimicrobial and antibiofilm activity and inhibited the growth of most of the examined microorganisms. The obtained results indicate the potential role of the tested extracts in pharmacy and medicine.