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This is the first report on morpho-anatomical and phytochemical differentiation of 19 native populations representing different Pinus nigra J.F.Arnold subspecies (banatica (Borbás) Novák, dalmatica (Vis.) Franco, nigra, and pallasiana (Lamb.) Holmboe) in the Balkans and Southern Carpathians. The 9 morpho-anatomical characteristics and 10 headspace volatiles of needles were analyzed with multivariate statistical analyses. The combination of results from all multivariate analyses with both types of markers revealed that P. nigra is differentiated into three groups within the studied area (the Dalmatian coast, Greece, and the rest of the Balkans with the Southern Carpathians). The first group included the population from an island in Dalmatia that corresponds to P. nigra subsp. dalmatica. The third group consisted of populations from continental Croatia, Bosnia and Herzegovina, Serbia, Romania, and Bulgaria, which corresponds to P. nigra subsp. nigra. In light of the recent molecular data that indicated that the Greek populations (the second group) represent a distinct genetic lineage of P. nigra placed between the populations from the principal area (P. nigra subsp. nigra) and Turkey (P. nigra subsp. pallasiana), one can speculate that there is one more subspecies of P. nigra in this region that corresponds to populations from Greece. Extending our analyses to Asia Minor and Crimea could bring additional results that would be valuable for clarifying the intriguing issue of the diversification of P. nigra in the eastern part of its range.

The concept of the genus Clinopodium L. has changed considerably since its first description. Most of the currently accepted species of the genus have traditionally been treated as separate genera in the group Satureja sensu lato: Clinopodium L., Calamintha sensu Miller or Moench, and Acinos sensu Miller or Moench. This study aimed to gain a better insight into the species diversity of Clinopodium L. from the Balkans by analyzing the taxa that have traditionally been placed in separate genera. The alkane profile and the micromorphological characteristics of the leaves are analyzed. The leaves are visualized using scanning electron microscopy, and alkanes are isolated using n-hexane as a solvent and analyzed using gas chromatography/mass spectrometry. The alkane profile showed the differentiation of the Acinos-group from the other taxa based on the dominant n-C31, while most of the other taxa contained n-C33 as the dominant alkane. The micromorphological features also showed clear differences between the previously recognized genera, especially in the capitate trichomes. The results showed that micromorphological patterns are highly variable in certain groups of the genus Clinopodium.

In this study we have reported the chemical composition of the essential oils obtained from the needles of twelve Pinus taxa, belonging to the subgenera Pinus (sections Pinus and Trifoliae) and Strobus (sect. Quinquefoliae). Monoterpenes dominated over sesquiterpenes in most of the investigated taxa of both subgenera, except in representatives of the subsection Pinaster, subgenus Pinus. α-Pinene was the most abundant terpene in eight pines, but other dominant terpenes were found in some taxa - trans-caryophyllene, germacrene D, abietadiene and β-pinene. In the subsect. Pinaster, the most dominant compounds varied from species to species. In addition, P. halepensis and P. pinaster had the highest percentage of diterpenes, while P. heldreichii was the richest in germacrene D. In the PCA and cluster analyses, three species from the subsect. Pinaster emerged as the most distant: P. halepensis, P. pinaster, and P. heldreichii. In addition, the possible taxonomic implications of the terpene profile in the analysed Pinus taxa were also discussed.

The berries of Rubus discolor are considered a rich source of phytochemicals which could play an important role in the prevention of prevalent contemporary chronic diseases. Thus, the goal of the presented study was to determine the profile of phenolic acids and anthocyanins of aqueous and ethanol extracts of R. discolor fruit, and their free radical scavenging, antiproliferative, antidiabetic and antimicrobial activities. LC-MS/MS analyses confirmed the presence of 11 phenolic acids with protocatechuic and gallic acids being the major compounds. Additionally, cyanidin- glucoside/galactoside was the most abundant among the five identified anthocyanins. The ethanol extract was more efficient in scavenging free radicals than the aqueous extract. The absence of antiproliferative activity was observed for both extracts. However, they inhibited carbohydrate hydrolysing digestive enzymes associated with type-2 diabetes. Furthermore, the obtained results for α-glucosidase inhibitory activity (IC50 values 44.52 and 80.72 μg/mL, for the aqueous and ethanol extracts, respectively) indicate significantly higher activity than the positive control, GlucobayR (233.38 μg/mL). The ethanol extract was more effective against all of the examined bacteria (Bacillus cereus, Staphylococcus aureus and Enterobacter cloacae) than the aqueous extract. On the contrary, the aqueous extract showed better antifungal properties, particularly against Trihoderma viride and Penicillium verrucosum var. cyclopium. The quantified phenolics and presented bioactivities of R. discolor fruit extracts candidate them as a potential source of bioactive compounds which might be used in the food, pharmacy and cosmetic industries

This study was aimed at evaluating the antioxidant and antidiabetic activities of methanolic extracts of peel, flesh and mixed peel, and flesh, as well as the cytotoxic activity of mixed peel and flesh extracts obtained from fruits of six traditional pear varieties (Vidovača, Lubeničarka, Karamanka, Jeribasma, Lončara and Takiša), one commercial variety (Williams Bartlett) and a wild pear (Pyrus communis) from Serbia. The tested extracts showed strong antioxidant activity regarding the prevention of β-carotene bleaching and high α-glucosidase inhibition, and no significant cytotoxic potential, with the exception of the Williams Bartlett and Pyrus communis extracts. Overall, the most potent fruit part was shown to be the peel. The most active variety in all of the applied antioxidant and antidiabetic assays was Takiša, while the wild pear, P. communis, was the most effective in inhibiting the proliferation of cancer cells. In conclusion, several methanolic extracts of pear fruit are promising candidates for further studies regarding the prevention and treatment of pathological conditions associated with the effects of oxidative stress, such as diabetes and even colorectal cancer

Pear ( Pyrus communis L.) is consumed as fresh fruit, in numerous food products, and also used as a traditional remedy in various countries, including Serbia. In search of bioactive compounds, six traditional pear varieties (‘Vidovača’, ‘Lubeničarka’, ‘Karamanka’, ‘Jeribasma’, ‘Lončara’, ‘Takiša’) and wild pear from Serbia were investigated and compared with a commercial variety (‘Williams Bartlett’). The aim of this study was to determine the total phenolic and flavonoid contents, phenolic composition, antioxidant capacity, and antineurodegenerative activities of methanolic extracts of peel, flesh, and mixed peel and flesh of pear fruits. Phenolic composition of extracts was determined with HPLC-DAD, while the antioxidant activity of extracts was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric-reducing antioxidant power (FRAP) assays. Bearing in mind that oxidative stress is closely linked to neurodegeneration, the antineurodegenerative potential of the extracts was assessed by the inhibition of acetycholineserase (AChE) and tyrosinase (TYR) activities. The extracts of traditional varieties, particularly peel extracts, had a high content of phenolics, as well as significant antioxidant and moderate antineurodegenerative potential, compared to the commercial variety. The highest contents of total flavonoids and individual compounds, such as arbutin and chlorogenic acid, as well as the strongest antioxidant and TYR inhibitory activities were reported for the ‘Takiša’ peel extract. The performed analyses have revealed that fruits of traditional Serbian pear varieties are rich in bioactive components and could be used as functional food and for possible nutraceutical applications, to prevent diseases induced by oxidative stress.

In this study, the vegetative anatomy of Artemisia umbelliformis subsp. eriantha, a Central European alpine glacial relict, wild-growing on Mt. Durmitor (Montenegro) was examined for the first time. The aim was to investigate the general anatomy and particular anatomical traits which might have possible taxonomic value. Microscopic slides were prepared according to the standard histological procedures. The adventitious young root showed a primary structure, while the older root showed a secondary structure with a well-developed periderm on its surface. The rhizome showed a primary structure with elements of a secondary structure (periderm). The stem cross section is characterized by a round shape with a well-developed periderm at certain stages, and collateral vascular bundles arranged in a circle. The petiole is concave in shape with a single-layered epidermis and parenchyma tissue with one large and two small vascular bundles. Druses and rhombohedral crystals are observed inside some petiole parenchyma cells. The leaf lobe cross section has an oblong-linear shape and is isolateral and amphistomatous in structure. The anticlinal walls of the leaf epidermal cells are sinuate. Secretory canals are present in the root cortex parenchyma (endodermal secretory canals) and the rhizome cortical parenchyma. The stem, petiole and leaf lack secretory canals. The stem and leaf are covered with T-shaped non-glandular and glandular trichomes. The taxonomic value of the analyzed characteristics is briefly discussed.

The main objective of this research was to evaluate the impact of methanolic, ethanolic and aqueous extracts of Origanum majorana L., Origanum vulgare L., Teucrium chamaedrys L., Teucrium montanum L., Thymus serpyllum L. and Thymus vulgaris L. (Lamiaceae) on the effects of free radicals using different model systems. The extracts were characterized on the basis of the contents of total phenolics, phenolic acids, flavonoids and flavonols, and also using high-performance liquid chromatography with diode-array detection. Antioxidant activity in vitro was assessed using DPPH assay. The genoprotective properties were tested using plasmid relaxation assay on pUC19 E. coli XL1-Blue, while SOS/umuC assay on Salmonella typhimurium TA1535/pSK1002 and Comet assay on human lung fibroblasts were used to assess the antigenotoxicity of the extracts. Ethanolic extracts had the most phenolics (up to 236.20 mg GAE/g at 0.5 mg/mL), flavonoids (up to 42.47 mg QE/g at 0.5 mg/mL) and flavonols (up to 16.56 mg QE/g at 0.5 mg/mL), and they exhibited the highest DPPH activity (up to 92.16% at 0.25 mg/mL). Interestingly enough, aqueous extracts provided the best protection of plasmid DNA (the lowest IC50 value was 0.17 mg/mL). Methanolic extracts, on the other hand, most efficiently protected the prokaryotic DNA, while all the extracts had a significant impact against genomic damages inflicted on human fibroblasts. O. vulgare extracts are considered to be the most promising in preserving the overall DNA integrity against oxidative genomic damages. Moreover, HPLC-DAD analysis highlighted rosmarinic acid as the most abundant in the investigated samples (551.45 mg/mL in total in all the extracts), followed by luteolin-7-O-glucoside (150.19 mg/mL in total), while their presence correlates with most of the displayed activities. The novelty of this study is reflected in the application of a prokaryotic model for testing the antigenotoxic effects of Lamiaceae species, as no previous reports have yet been published on the genoprotective potential of these species.

The variability of n-alkanes in the needle cuticular wax of Pinus heldreichii and P. peuce in two natural populations from the Scardo-Pindic mountains was investigated for the first time. Gas chromatography (GC) and gas chromatography/mass spectrometry (GC–MS) analyses of two-year-old needles were performed using an Agilent 7890A GC equipped with an inert 5975C XL EI/CI mass spectrometer detector (MSD) and a flame ionization detector (FID) connected by a capillary flow technology 2-way splitter with make-up. An HP-5MS capillary column was used. n-Alkanes ranged from C19 to C33. In P. heldreichii the most abundant were C23, C25 and C27 (16.3, 15.6 and 12.8% on average, respectively), while in P. peuce they were C29, C25, and C27 (16.5, 15.3 and 13.5% on average, resp.). Mid-chain and long-chain n-alkanes prevailed in both species. Principle component analysis (PCA) and Cluster analyses of five and six n-alkanes, respectively, showed divergence of the Scardo-Pindic populations from the Dinaric ones.

In this study, micromorphology of an involucral bract and inner and outer dimorphic cypselae of the relict Amphoricarpos elegans, endemic from western Caucasus, is examined using a scanning electron microscope (SEM) and presented here for the first time. The middle involucral bract is nearly glabrous, with a reticulate-rugulose surface and an oblong-obtusate mucro. Both cypselae exhibit similar features, viz., narrowly oblong-cylindrical or obovate shape with more or less conspicuous longitudinal ribs, an adaxial detachment area, an asymmetrical carpopodium, absence of a pericarp crown and a barbate-aristate pappus made up of narrow, subulate, basally smooth and apically barbate bristles. However, some differences are evident. The outer cypsela is glabrescent and flattened, with an obscure outline of epidermal cells lacking an end wall and with a sunken periclinal surface and striatereticulate structure. Also, the outer cypsela has two entire, narrow, lateral wings, rounded above; and less numerous pappus bristles in one row. In contrast to this, the inner cypsela has a distinct outline of the epidermal cells, which are rod-shaped with a short acute end wall, a swollen periclinal surface and reticulate structure. The pappus of the inner cypsela possesses many more bristles organised in two rows (a biseriate pappus). Also, slightly pentagonal or round nectary remnants are found in the centre of the upper part of the inner cypsela. The taxonomic value of the analysed characters is briefly discussed

Juniperus sabina L. var. balkanensis R.P. Adams & Tashev is a recently described endemic variety from the Balkan Peninsula. Its strong sprouting ability and fast vegetative propagation, on one hand, and fragmented distribution, on the other, can lead to lower genetic diversity in local populations and to the differentiation of populations. As there has been no detailed investigation of this variety, we studied Balkan natural populations using phytochemical and molecular markers. Leaf essential oils (EOs) were chosen based on their proven usability in the population studies of Juniperus taxa, while ISSRs (Inter Simple Sequence Repeats) have been used due to their high resolution. In addition, since this variety is best described using molecular markers, the chloroplast trnS-trnG region was amplified from individuals from different populations having different chemotypes. Based on the essential oil profile, three chemotypes could be identified with a difference in their distribution. The analysis of molecular variance showed moderate differentiation of populations and regions, attesting to the start of the separation of three regions in the Balkans: west, east and south. The bioclimatic and environmental parameters and sex of the individual did not influence the EO profile, although some of the compounds present in low-to-medium concentrations showed strong correlation with several bioclimatic parameters.

Plant-based natural products have been used as a source for therapeutics since the dawn of civilization. According to the World Health Organization (WHO), more than 80% of the world’s population relies on traditional medicine for their primary healthcare. Numerous natural extracts, widely known in Traditional Chinese Medicine, Indian Ayurveda medicine and other practices, have led to the modern discovery and development of new drugs. Plants continuously interact with their environment, producing new compounds and ever-changing combinations of existing ones. Interestingly, some of the compounds have shown lower therapeutic activity in comparison to the extract they were isolated from. These findings suggest that the higher therapeutic activity of the source extract was due to the synergistic effect of several compounds. In other words, the total therapeutic potential of the extract cannot be explained only by the sum of its parts alone. In traditional medicine, most herbal remedies are based on a mixture of plants, and it is the interaction between different constituents that amplifies their therapeutic potential. Considering the significant influence traditional medicine has on human healthcare, knowing and studying the synergistic effect of compounds is paramount in designing smart therapeutic agents.

Nepeta cyrenaica Quézel & Zaffran (Lamiaceae), an endemic species of the Libyan flora, has been scarcely explored until now. Since Nepeta species are proven as pharmacologically active plants rich in iridoid monoterpenes, this study was aimed to quantify the iridoids present in different extracts of in vitro propagated N. cyrenaica. The seeds collected from their natural habitat were germinated. One node stem explant of 5-week-old plants were used for plant micropropagation. After several cycles, the shoots were harvested. The extraction was performed using maceration procedure by dichloromehane, methanol, 96% ethanol, and hot distilled water. Subsequently, the extracts were subjected to UHPLC/(±)HESI-MS2 analysis of iridoids. Two iridoids were identified and quantified, namely epideoxyloganic acid and nepetalactol, as well as their precursor 8-oxogeranial. Iridoid glucoside epideoxyloganic acid was the most abundant in the methanolic and ethanolic extracts (1255.37 and 1262.78 µg/100 g dry extract), followed by aqueous extract. On the other hand, 8-oxogeranial and nepetalactol reached maximal amounts in the dichloromethane extract (476.80 and 1039.52 µg/100 g dry extract, respectively). The results of this study indicate that the high antioxidant and enzyme-inhibiting effects of dichloromethane extract confirmed in our previous study could be attributed to its iridoid content, which was particularly high due to the low polarity of this extraction solvent. In conclusion, endemic N. cyrenaica could be efficiently propagated in vitro as an iridoid-rich plant with great biological potential.

Citrus reticulata (mandarin) is used in the food industry mainly for juice production, while its peel represents a byproduct with a high content of miscellaneous biologically active compounds. This research aimed to assess the antioxidant and enzyme-inhibitory activities of different peel extracts of mandarin cultivated under natural conditions in the Montenegrin coastal region (Lastva Grbaljska). Mandarin fruits were collected in November 2017, and their extracts were prepared using acetone, methanol, and boiling distilled water as solvents. Total phenolic (TPC) and flavonoid (TFC) contents were determined at the concentration of 0.5 mg/mL, as well as the extracts’ antioxidant (using DPPH and total reducing power assays) and enzyme-inhibitory activities (using acetylcholinesterase (AChE) and α-glucosidase inhibition assays). The results indicated that the acetonic extract exhibited the highest radical scavenging activity (12.70%) while also showing the highest TPC (52.40 mg GAE/g) and TFC (13.05 mg QE/g), which is not surprising since acetone is known to extract highly biologically active flavonoid aglycones from plants. Although the aqueous extract had the lowest TPC and TFC, it exerted the highest reducing power (199.06 µmol AAE/g), as well as AChE inhibition activity (22.44%), indicating that other groups of phytochemicals besides phenolics, such as various classes of glycosides, are responsible for the displayed bioactivity. Moreover, none of the extracts inhibited the activity of α-glucosidase. Finally, this study suggests that mandarin peel should not be dismissed in food processing since it possesses a valuable medicinal potential that has yet to be further investigated.

Sage (Salvia officinalis) is the best-known species of the genus Salvia, due to its medicinal and flavouring properties. This research was conducted on samples of S. officinalis collected from Potoci (SOP) in the continental part of Montenegro and from Valdanos (SOV) and Luštica (SOL) in the country´s coastal region. Extracts prepared using 96% ethanol, 50% ethanol and hot distilled water were examined for phenolic composition, as well as for their antioxidant, enzyme-inhibiting and cytotoxic activities. The HPLC-DAD method was employed for quantitative-qualitative analysis of phenolic compounds in extracts, which confirmed the presence of rosmarinic and caffeic acids and luteolin-7-O-glucoside. Total phenolic and flavonoid contents, antioxidant activity, and inhibition of acetylcholinesterase and tyrosinase were measured spectrophotometrically. In the applied antioxidant tests (DPPH, FRAP and β-carotene/linoleic acid tests) and tests of inhibition of the enzymes acetylcholinesterase and tyrosinase, the SOP extracts showed stronger antioxidant and enzyme-inhibiting activities compared to SOV and SOL, while the most efficient solvent was 50% ethanol. The highest cytotoxic activity in the MTT test was recorded for 96% ethanol extracts, especially in the case of the SOL sample, against the A375 cell line. All of the tested bioactivities were more strongly correlated with total phenolic content than with flavonoid content. Differences in the tested bioactivities of extracts obtained from plants collected at ecologically different localities and with different extraction

Groups of recent speciation are characterized by high levels of introgression and gene flow, which often confounds delimitation of species on a DNA basis. We analyzed nuclear DNA sequences (ETS spacer and the AGT1 gene) obtained from a large sample of the C. calocephala complex from the Balkan clade of Centaurea sect. Acrocentron (Compositae, Cardueae-Centaureinae) together with a wide representation of other species from the section. Our main goals were to verify the monophyly of the complex as currently defined and to examine the possible presence of introgression and gene flow. Within the complex, species are well-delimited from a morphological point of view and probably originated by allopatric speciation in the Balkan Peninsula. Our results confirm that the Balkan–Eurasian complex is a natural group, but the Centaurea calocephala complex shows a very complicated pattern and its phylogeny is not resolved. Our hypothesis suggests that altitudinal shifts in the transits from glacial to interglacial periods caused successive hybridization events, which are very evident from the DNA networks, between taxa not currently sympatric. As a result, confirmation of interspecific boundaries using molecular markers is extremely complicated.

Prunus spinosa leaf extracts in solvents of different polarity (water, ethanol and acetone), their phenol, flavonoid and anthocyanin contents and biological properties were the object of this study. The richest in phenols as well as in flavonoids was acetone extract with 181.19 mg GAE and 80.10 mg QE per gram of dry extract, respectively. Moreover, the quantity of anthocyanins obtained by HPLC analysis was also the highest in acetone sample. Examined samples possessed antioxidant properties evaluated through four in vitro assays (DPPH, ABTS, FRAP and TRC). The acetone extract was proved to be the best antioxidant among tested samples, which could be ascribed to polyphenols, especially anthocyanins. The aqueous and the ethanol extract exhibited antibacterial effects, being particularly active against B. cereus and E. cloacae. T. viride, P. funiculosum, P. ochrochloron, P. verrucosum var. cyclopium were the most susceptible among fungal microorganisms examined. Both, the aqueous and the ethanol extract expressed inhibitory activity towards enzymes linked to diabetes mellitus type II. Additionally, the ethanol extract showed significantly higher potential in inhibiting α-glucosidase than the drug used as the positive control. Furthermore, the aqueous sample revealed antitumor effects on following malignant cell lines: HeLa, K562 and MDA-MB-453. The results presented herein suggest that P. spinosa leaves should be considered as a natural source of bioactive compounds with potential application in phytopharmacy and food industry.

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.

This study was designed to evaluate the genoprotective, antigenotoxic, as well as antitumor potential of methanolic, ethanolic, and aqueous extracts of Melissa officinalis, Mentha × piperita, Ocimum basilicum, Rosmarinus officinalis, Salvia officinalis, and Satureja montana (Lamiaceae), in different model systems. The polyphenols in these extracts were quantified both spectrophotometrically and using HPLC-DAD technique, while DPPH assay was used to assess the antioxidant activity. The genoprotective potential was tested on pUC19 Escherichia coli XL1-blue, and the antigenotoxicity on Salmonella typhimurium TA1535/pSK1002 and human lung fibroblasts, while the antitumor activity was assessed on colorectal cancer cells. Rosmarinic acid, quercetin, rutin, and luteolin-7-O-glucoside were among the identified compounds. Methanolic extracts had the best DPPH-scavenging and SOS-inducing activities, while ethanolic extracts exhibited the highest antigenotoxicity. Additionally, all extracts exhibited genoprotective potential on plasmid DNA. The antitumor effect was mediated by modulation of reactive oxygen species (ROS), nitric oxide (NO) production, and exhibition of genotoxic effects on tumor cells, especially with O. basilicum ethanolic extract. Generally, the investigated extracts were able to provide antioxidant protection for the acellular, prokaryotic, and normal human DNA, while also modulating the production of ROS and NO in tumor cells, leading to genotoxicity toward these cells and their decrease in proliferation.

Based on previous investigations where bis-bibenzyls isolated from liverworts showed various biological activities (cytotoxic, antimicrobial, and antiviral), we investigated their cytotoxic activity in several human cancer cell lines. From the methylene-chloride/methanol extract of the liverwort Pellia endiviifolia, three bis-bibenzyls of the perrottetin type were isolated, namely perrottetin E, 10′-hydroxyperrottetin E, and 10,10′-dihydroxyperrottetin E. The last two were found for the first time in this species. Their structures were resolved using 1D and 2D NMR, as well as by comparison with data in the literature. Cytotoxic activity of the isolated compounds was tested on three human leukemia cell lines, HL-60 (acute promyelocytic leukemia cells), U-937 (acute monocytic leukemia cells), and K-562 (human chronic myelogenous leukemia cells), as well as on human embryonal teratocarcinoma cell line (NT2/D1) and human glioblastoma cell lines A-172 and U-251, and compared to the previously isolated bis-bibenzyls (perrottetins) of similar structure. The isolated compounds exhibited modest activity against leukemia cells and significant activity against NT2/D1 and A-172. Overall, the most active cytotoxic compounds in this investigation were perrottetin E (1), isolated in this work from Pellia endiviifolia, and perrottetin F phenanthrene derivative (7), previously isolated from Lunularia cruciata and added for a comparison of their cytotoxic activity.

The essential oil (EO) composition of Satureja plants is highly variable. Recent studies suggest that there is an even difference in the EO composition from different plant organs within the same plant. This study aims to examine the chemical profile of EOs and the micromorphological characteristics of different organs of three Satureja species. The relationship between the number of glandular trichomes and EOs profile and relative yield is also investigated. Individuals from five populations were visualized using a scanning electron microscope, while EOs of leaves, calyces, corollas, and whole aerial parts were isolated using simultaneous distillation and extraction and analyzed using gas chromatography/mass spectrometry. Three types of glandular trichomes were detected. Peltate trichomes were present on all plant organs of studied species, while two types of capitate trichomes show different organ and species preferences. The EOs profiles differed across the plant parts, but showed a species specific composition. Univariate and multivariate statistics were used to show a correlation between the peltate trichomes and EO yield, and chemophenetic significance of EO profiles.

The aim of this study was to examine chemical composition, as well as antineurodegenerative, antioxidant and antibacterial activity of aqueous and ethanolic extracts of Origanum majorana L. (Lamiaceae) originating from Serbia, Greece, Egypt and Libya. Total phenolics and flavonoids, antioxidant activities, and acetylcholinesterase and tyrosinase inhibitory activities were measured spectrophotometrically. Determination of phenolic compounds in extracts was done using HPLC-DAD technique. Antibacterial activity included determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. The highest phenolic and flavonoid contents were recorded in the ethanolic extract of the Egyptian sample and in aqueous extract of Serbian sample. The HPLC analysis showed high content of rosmarinic acid, with the highest amount found in the ethanolic extract of the plants from Egypt. Water extracts showed prevalently better antioxidant and antineurodegenerative activity in applied tests than the ethanolic extracts. Gram-positive bacterial strains showed higher sensitivity to tested extracts. According to the obtained results, sweet marjoram samples from Serbia and Egypt can be marked as more promising, due to the highest content of total phenolics and flavonoids and the best antioxidant, antibacterial and tyrosinase inhibitory activity.

Chemical constituents of liverwort (Porella cordaeana) extracts have been identified using solid-phase microextraction-gas chromatography mass spectrometry (SPME-GC/MS). The methanol, ethanol and ethyl acetate extracts were rich in terpenoids such as sesquiterpene hydrocarbons (53.12%, 51.68%, 23.16%), and monoterpene hydrocarbons (22.83%, 18.90%, 23.36%), respectively. The dominant compounds in the extracts were β-phellandrene (15.54%, 13.66%, 12.10%) and β-caryophyllene (10.72%, 8.29%, 7.79%, respectively). The antimicrobial activity of the extracts was evaluated against eleven food microorganisms using the microdilution and disc diffusion methods. The minimum inhibitory concentration (MIC) varied from 0.50 to 2.00 mg/mL for yeast strains (Saccharomyces cerevisiae 635, Zygosacharomyces bailii 45, Aerobasidium pullulans L6F, Pichia membranaefaciens OC 71, Pichia membranaefaciens OC 70, Pichia anomala CBS 5759, Pichia anomala DBVPG 3003 and Yarrowia lipolytica RO13), and from 1.00 to 3.00 mg/mL for bacterial strains (Salmonella enteritidis 155, Escherichia coli 555 and Listeria monocytogenes 56Ly). Methanol extract showed better activity in comparison with ethanol and ethyl acetate extracts. High percentages of monoterpene and sesquiterpene hydrocarbons could be responsible for the better antimicrobial activity.

The composition of essential oil isolated from Satureja thymbra, growing wild in Libya, was analyzed by GC and GC-MS. The essential oil was characterized by γ-terpinene (39.23%), thymol (25.16%), p-cymene (7.17%) and carvacrol (4.18%) as the major constituents. Antioxidant activity was analyzed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. It possessed strong antioxidant activity (IC50 = 0.0967 mg/mL). The essential oil was also screened for its antimicrobial activity against eight bacterial and eight fungal species, showing excellent antimicrobial activity against the microorganisms used, in particular against the fungi. The oil of S. thymbra showed bacteriostatic activity at 0.001–0.1 mg/mL and was bactericidal at 0.002–0.2 mg/mL; fungistatic effects at 0.001���0.025 mg/mL and fungicidal effects at 0.001–0.1 mg/mL. The main constituents thymol, carvacrol and γ-terpinene also showed strong antimicrobial activity. The commercial fungicide bifonazole showed much lower antifungal activity than the tested oil.

This is the first report of n-alkanes in needle epicuticular waxes of the variety Bosnian pine, Pinus heldreichii var. pančići. n-Hexane extracts of needle samples, originating from seven isolated localities in Serbia, were analysed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). The results evidenced n-alkanes ranging from C18 to C33 in epicuticular waxes. The most abundant alkanes were C27, C23, C25 and C29 (12.53 %, 12.46 %, 12.00 % and 10.38 % on average, respectively). The carbon preference index (CPItotal) of Pinus heldreichii var. pančići ranged from 1.1 to 2.1 (1.6 on average), while the average chain length (ACLtotal) ranged from 25.0 to 25.8 (25.3 on average). A high level of individual quantitative variation in all of these hydrocarbon parameters was also found. The obtained results were compared with the bibliographic references for Pinus heldreichii var. leucodermis and other species of the Pinus genus.

The chemical composition and antibacterial activity of essential oils from 10 commonly consumed herbs: Citrus aurantium, C. limon, Lavandula angustifolia, Matricaria chamomilla, Mentha piperita, M. spicata, Ocimum basilicum, Origanum vulgare, Thymus vulgaris and Salvia officinalis have been determined. The antibacterial activity of these oils and their main components; i.e. camphor, carvacrol, 1,8-cineole, linalool, linalyl acetate, limonene, menthol, a-pinene, b-pinene, and thymol were assayed against the human pathogenic bacteria Bacillus subtilis, Enterobacter cloacae, Escherichia coli O157:H7, Micrococcus flavus, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enteritidis, S. epidermidis, S. typhimurium, and Staphylococcus aureus. The highest and broadest activity was shown by O. vulgare oil. Carvacrol had the highest antibacterial activity among the tested components.

The potential antifungal effects of Thymus vulgaris L., Thymus tosevii L., Mentha spicata L., and Mentha piperita L. (Labiatae) essential oils and their components against 17 micromycetal food poisoning, plant, animal and human pathogens are presented. The essential oils were obtained by hydrodestillation of dried plant material. Their composition was determined by GC-MS. Identification of individual constituents was made by comparison with analytical standards, and by computer matching mass spectral data with those of the Wiley/NBS Library of Mass Spectra. MIC’s and MFC’s of the oils and their components were determined by dilution assays. Thymol (48.9%) and p-cymene (19.0%) were the main components of T. vulgaris, while carvacrol (12.8%), a-terpinyl acetate (12.3%), cis-myrtanol (11.2%) and thymol (10.4%) were dominant in T. tosevii. Both Thymus species showed very strong antifungal activities. In M. piperita oil menthol (37.4%), menthyl acetate (17.4%) and menthone (12.7%) were the main components, whereas those of M. spicata oil were carvone (69.5%) and menthone (21.9%). Mentha sp. showed strong antifungal activities, however lower than Thymus sp. The commercial fungicide, bifonazole, used as a control, had much lower antifungal activity than the oils and components investigated. It is concluded that essential oils of Thymus and Mentha species possess great antifungal potential and could be used as natural preservatives and fungicides.

The volatile composition of two Eryngium species was studied. The es­sen­tial oils were obtained by hydrodistillation in a modified Clevenger-type appara­tus, and their analyses were performed by GC and GC–MS. A total of 58 different compounds were identified. Their main constituents were as follows: E. serbicum: germacrene D (19.7 %), b-elemene (10.0 %) and spathulenol (6.9 %); E. palmatum: sesquicineole (21.3 %), caryophyllene oxide (16.0 %), spathulenol (16.0 %) and sa­binene (5.5 %). The main portion in both studied taxa consisted of sesquiterpenes.