This work presents investigation of chemical composition and antioxidant activity of ethanolic extracts of leaves with flowers and berries prepared by ultrasound and Soxhlet extractions of Crataegus monogyna from Bosnia and Herzegovina. Total phenolic, flavonoid, and anthocyanin contents were measured by spectrophotometric methods. The sample of leaves with flowers extracted by Soxhlet extraction was the richest in the content of total phenolic compounds (14.43 mg GAE/g DW) and total flavonoids (2.22 mg QE/g DW). Same extract showed the best antioxidant activity with an IC50 value of 0.71 mg/mL for DPPH and 0.38 mg/mL for ABTS assay, as well as the highest content of gallic acid, caffeic acid, and hyperoside 0.04 mg GAE/g DW, 0.60 mg CA/g DW and 2.61 mg HYP/g DW, respectively, determined by HPLC-ED. Vitexin was not detected. The extract of berries obtained by ultrasound extraction had the highest amount of total anthocyanins (1.69 mg/100 g DW).

Chlorogenic acid, an ester of caffeic acid with quinic acid, also known as 5- O-caffeoylquinic acid (5-CQA), is a ubiquitous plant constituent that is an important intermediate in lignin biosynthesis. In some cases, it occurs at surprisingly high levels in the leaves and fruits of certain higher plants, such as coffee beans. Due to its catechol moiety and an extended side chain conjugation, it easily forms a resonance-stabilised phenoxy radical, accounting for its powerful antioxidant potential. The objective of this work was to determine if the esterification and methylation of 5- CQA would enhance its antioxidant activity. Two 5-CQA derivatives were prepared for this study. Chlorogenic acid was esterified with methanol over Amberlite IR120-H to obtain methyl chlorogenate, while methyl 3',4´-dimethyl chlorogenate was prepared from 5-CQA by treatment with diazomethane. Spectroscopic methods confirmed the structure of these derivatives. Their antioxidant properties were tested to establish a relationship between structure and antioxidant activity. Antioxidant activity results were generated for 5-CQA and its ester analogues using eight different methods. Depending on the method applied, results were expressed as IC50/MCE50 values or as equivalents of the applied standard (ascorbic acid and Trolox). In most of these tests, 5-CQA showed the highest antioxidant activity compared to its derivatives. Nevertheless, due to their hydrophobic characteristics, their ester analogues remain promising antioxidant candidates in emulsifying systems.

: Phenolic aldehydes and their derivatives found in nature are well-known for their potential biological activity. In this study, four 1-substituted 1,2,3,4-tetrahydroisoquinolines (THIQs) derived from phenolic aldehydes were synthesized by phosphate buffer mediated Pictet-Spengler reaction. All derivatives were chemically and structurally characterized by elemental CHN analysis and spectroscopic methods (IR, HR-ESI-MS, 1 H-and 13 C-NMR). 1-Substituted THIQs derived from 3,4-dihydroxybenzaldehyde and 4-hydroxy-3-methoxybenzaldehyde were described for the first time. In order to cover the diversity of the mechanistic approach, but also to establish the relationship between structure and activity, antioxidant activity was examined by five different in vitro methods, namely: neutralization and reduction of stable free radicals 2,2-diphenyl-1-picrylhydrazyl and radical cation derived from [(2,2´-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)], ferric reducing antioxidant power, oxygen radical absorbance capacity, and ability to chelate Fe(II) ions. In vitro inhibition of acetylcholinesterase (AChE) was examined by the Ellman's colorimetric method, while computer-simulated docking was used to reveal the preferred binding site and major interaction between AChE and THIQs. Antibacterial testing was examined using the agar well method and results were presented in the form of zones of inhibition (mm).

: The samples of Clinopodium nepeta (L.) Kuntze (Lamiaceae) aerial parts were collected from four different localities in sub-Mediterranean area of Bosnia and Herzegovina and subjected to phytochemical profiling. Shade-dried and fresh samples were used to determine their headspace volatile organic composition by solid-phase microextraction on two differently coated fibers. Corresponding essential oils were obtained by hydrodistillation. Both headspace and essential oil were analysed by gas chromatography-mass spectrometry Among detected compounds, piperitenone oxide and pulegone were dominant in the headspace of shade-dried and fresh C. nepeta samples. The essential oils contained 42 compounds including pulegone (44.8%), piperitenone (48.8%) and piperitenone oxide (60.2%) as the major compounds, followed by limonene, cis piperitone oxide, p -menthone and dihydrocarvyl acetate. In this work, a wide range of volatile compounds present in C. nepeta samples from Bosnia and Herzegovina was determined. The obtained data provides detail phytochemical analysis of the volatiles of C. nepeta and therefore completes earlier researches of this plant from the other geographical areas.

In this study, the chemical composition and antioxidant activity of the hydrodistilled essential oil of Achillea lingulata, an endemic species of the Euro-Mediterranean region, originating from Bosnia and Herzegovina, was investigated for the first time. For comparison, an analysis of the essential oil of the widely distributed Achillea millefolium, which grows together in the same habitat, was made. Ninety-six components were identified in A. lingulata and A. millefolium oils comprising 97.8% and 85.8%, of the total oil, respectively. The oil of A. lingulata was characterized by a high content of oxygenated monoterpenes (76.8%). The main compounds were borneol (30.1%), trans-verbenol (15.5%), 2-tridecanone (12.2%), fragranol (8.3%), and myrtenol (7.9%). In contrast, essential oil of A. millefolium had oxygenated sesquiterpenes (60.8%) as the most abundant compounds, with elemol (32.9%) as the main constituent. In addition, γ-eudesmol (12.9%), caryophyllene oxide (7.7%), transcaryophyllene (5.7%) and γ-muurolene (4.7%) were present in a significant percentage in A. millefolium oil. Antioxidant activity was tested by three methods, ABTS, DPPH and FRAP, and the obtained results showed low activity of both investigated oils.

Volatile constituents of Satureja montana L. collected from a natural habitat in the southern region of Bosnia and Herzegovina were isolated by steam distillation and headspace sampling. The relative abundance of volatile compounds from the air-dried fragrant plant was analysed by GC-MS using two columns of different polarity. A total of 28 compounds were identified, constituting 93.5% of the essential oil composition. The GC pattern of headspace was different from that prepared by steam distillation. The former consisted of 14 compounds that made up 84.1% of the components identified. Both samples were dominated by oxygenated monoterpenes ranging from 55.2% for headspace of the plant material to 75.5% for the steam-distilled oil. Eleven alcohols represented the most diverse chemical class in the volatile oil (71.8%), as well as seven alcohols detected in the headspace (57.3%). GC-MS analysis of the volatiles indicates that S. montana belongs to linalool chemotype with its relative content of 38.7% for the essential oil and 23.7% for the headspace. With linalool as the most abundant constituent, the other major components were -terpineol (14.7%) in the essential oil, and cis-sabinene hydrate (21.8%) and p-cymene (17.9%) in the headspace sample. The results prove that the combined approach in the extraction of volatile compounds is reliable for the analysis of the aroma of complex herbal samples.

Volatile constituents of Satureja montana L. collected from a natural habitat in the southern region of Bosnia and Herzegovina were isolated both by steam distillation and headspace sampling. The relative abundance of volatile compounds from the air-dried fragrant plant was analysed by GC-MS using two columns of different polarity. A total of 28 compounds were identified, constituting 93.5% of the essential oil composition. The GC pattern of headspace was different from that prepared by steam distillation. The former consisted of 14 compounds that made up 84.1% of the components identified. Both samples were dominated by oxygenated monoterpenes ranging from 55.2% for headspace of the plant material to 75.5% for the steam-distilled oil. Eleven alcohols represented the most diverse chemical class in the volatile oil (71.8%), as well as seven alcohols detected in the headspace (57.3%). GC-MS analysis of the volatiles indicates that S. montana belongs to linalool chemotype with its relative content of 38.7% for the essential oil and 23.7% for the headspace. With linalool as the most abundant constituent, the other major components were terpineol (14.7%) in the essential oil, and cis-sabinene hydrate (21.8%) and p-cymene (17.9%) in the headspace sample. The results prove that the combined approach in the extraction of volatile compounds is needed for the analysis of the aroma of complex herbal samples.

In order to determine influence of extraction method on volatile oil composition of Artemisia annua L., steam distillation, hydrodistillation, organic solvent extraction, and headspace sampling have been applied. The relative abundance of volatile compounds from the odorous aerial parts of A. annua, obtained by different extraction techniques, was analyzed by GC-MS. Exactly fifty constituents were identified. The leaf and flower essential oil yield ranged from 0.9 to 2.3% (v/w). Oxygenated monoterpenes were predominant in all samples ranged from 42.6% for steam-distilled fraction of petroleum ether extract to 70.6% for headspace of plant material. Essential oils isolated by steam distillation and hydrodistillation indicate that A. annua belongs to artemisia ketone chemotype with its relative content of 30.2% and 28.3%, respectively. The principal constituent in headspace sample of plant material was also artemisia ketone (46.4%), while headspace of petroleum ether extract had camphene (25.6%) as the major compound. The results prove the combined approaches to be powerful for the analysis of complex herbal samples.

The aim of this work was the qualitative and quantitative determination of selected phenolic compounds in three Crataegus species grown in Bosnia. Crataegus plants are consumed for medicinal purposes and as foodstuff in the form of canned fruit, jam, jelly, tea, and wine. Two samples of plant material, dry leaves with flowers, and berries of three Crataegus species—Crataegus rhipidophylla Gand., Crataegus x subsphaericea Gand., and Crataegus x macrocarpa Hegetschw.—were analyzed. Twelve ethanolic extracts were isolated from the selected plant material using Soxhlet and ultrasound extraction, respectively. Soxhlet extraction proved to be more effective than ultrasound extraction. A simple and sensitive method, high-performance liquid chromatography with electrochemical detection, HPLC-ED, was used for the simultaneous determination of phenolic acids and flavonoids in Crataegus species. The content of gallic acid in the extracts ranged from 0.001 to 0.082 mg/g dry weight (DW), chlorogenic acid from 0.19 to 8.70 mg/g DW, and rutin from 0.03 to 13.49 mg/g DW. Two flavonoids, vitexin and hyperoside, commonly found in chemotaxonomic investigations of Crataegus species, were not detected in the examined extracts. In general, leaves with flowers samples are richer in gallic acid and rutin, whereas the berries samples are richer in chlorogenic acid. Distinct similarities were found in the relative distribution of gallic acid among the three species. Extracts of C. x macrocarpa had the highest content of all detected compounds, while significant differences were found in rutin content, depending on the plant organ. To the best of our knowledge, this is the first study reporting content of phenolic compounds in Crataegus rhipidophylla Gand., Crataegus x subsphaericea, and Crataegus x macrocarpa from Bosnia.

Phenolic acids and their derivatives found in nature are well-known for their potential biological activity. In this study, two amides derived from trans-caffeic/ferulic acid and dopamine were synthesized and characterized by Fourier-transform infrared spectroscopy (FTIR), mass spectrometry, proton and carbon-13 nuclear magnetic resonance spectroscopy. The compounds were tested for the inhibition of acetylcholinesterase (AChE) from Electrophorus electricus and for antioxidant activity by scavenging 2,2-diphenyl-1-pycrylhydrazyl free radical (DPPH•) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS•+), reducing ferric ions, and ferrous ions chelation. N-trans-Feruloyldopamine displayed the highest inhibitory effect on AChE with half-maximal inhibitory concentration (IC50) values of 8.52 μM. In addition, an in silico study was done to determine the most favorable AChE cluster with the synthesized compounds. Further, these clusters were investigated for binding positions at the lowest free binding energy. Both synthesized hydroxycinnamates were found to be better antioxidants than the parent acids in in vitro tests applied. N-trans-Caffeoyldopamine showed the best antioxidant activity in the three tested methods—against non-biological stable free radicals IC50 5.95 μM for DPPH•, 0.24 μM for the ABTS•+ method, and for reducing power (ascorbic acid equivalent (AAE) 822.45 μmol/mmol)—while for chelation activity against Fe2+ ions N-trans-feruloyldopamine had slightly better antioxidant activity (IC50 3.17 mM).

UDK: 633.88:547.56 This study aimed to analyse and compare the total phenolic content and the antioxidant activity of aqueous extracts of three medicinal plants: hibiscus (Hibiscus spp.), rosemary (Rosmarinus spp.) and savory (Satureja spp.). The plant extracts were prepared using maceration process. The total phenolic content was determined spectrophotometrically with the Folin-Ciocalteu reagent using gallic acid as a standard and the antioxidant activity was analysed using the Briggs-Rauscher reaction method. The inhibition times produced by plant extracts on an active Briggs-Rauscher oscillating reaction mixture were recorded potentiometrically. The total phenolic content was found 0.27, 1.29 and 1.43 mgGAE/g of dry extract for hibiscus, rosemary, and savory, respectively. Good correlation was found between the total phenolic content and the Briggs-Rauscher inhibition times (R2 = 0.994).

Abstract Hydrodistilled volatile oils from Achillea millefolium L., Arnica montana L., Artemisia absinthium L., and Artemisia annua L. were analyzed by GC/MS. One hundred sixty-seven compounds were identified in all samples, ranging from 74.3% to 96.4% of the total oil. A high percentage of oxygenated monoterpenes is the main characteristic of A. millefolium and A. absinthium oils with camphor (19.2%) and isoascaridol (21.9%) as the major constituents, respectively. In contrast, the main component of A. annua oil was oxygenated sesquiterpene selina-3,11-dien-6-α-ol (9.6%), while the chemical composition of A. montana oil was characterized by a high content of fatty acids with n-hexadecanoic acid (16.1%) as the main constituent. Antioxidant activity was tested using four different methods, DPPH, ABTS, Reducing power, and Phosphomolybdenum assay. The highest antioxidant activity had essential oil of A. montana using DPPH and Phosphomolibdenum assay, A. millefolium in ABTS method, while A. absinthium oil showed the best ability to reduce Fe ions.

The objective of this study was to determine total phenolic and flavonoid contents, antioxidant and antimicrobial activities of methanolic extracts from the leaves and barks of three Alnus species. The phenolic and flavonoid contents of extracts were determined spectrophotometrically using Folin–Ciocalteau and aluminium chloride methods, respectively. In addition, antioxidant activity of the extracts was determined using 1,1-diphenyl-2-picrylhydrazyl radical scavenging method. The antimicrobial activity was performed by disc diffusion assay against six reference bacterial strains including Gram-negative and Gram-positive bacteria and two fungal strains. Extract of Alnus viridis bark contained the highest amounts of total phenolics (780 mg CAT/g), while extract of A. viridis leaves had the highest amount of flavonoids (30.01 mg RUT/g). All extracts showed antioxidant activity higher than thymol, which was used as a positive probe. The largest diameters of inhibition zone (25 mm) were recorded with Bacillus subtilis 168 M and Staphylococcus aureus ATCC 6538.

BACKGROUND Calamintha glandulosa (Req.) Bentham is an aromatic perennial plant belonging to the family Lamiaceae, mostly found on rocky pastures, dry meadows, and abandoned places of the Mediterranean area. Plants belonging to this genus are known as highly aromatic and to possess significant antimicrobial and antifungal properties. The aim of this study was to provide clear picture of the volatiles of this plant species, and, for the first time, to present C. glandulosa from Croatia in terms of its antioxidant activity. RESULTS The essential oil and headspace obtained from odorous parts of C. glandulosa were subjected to capillary gas chromatography-mass spectrometry analysis. More than 50 volatile compounds were identified in six samples obtained using different extraction techniques. The most abundant components in all the samples examined were oxygenated monoterpenes, with piperitone (19.9-59.5%) and piperitenone (7.1-42.6%) as the main representatives. The total phenolic content of extracts obtained by successive Soxhlet extraction was measured, and the scavenging potency of the samples, indicated as IC50 values, were examined using four different spectrophotometric and spectrofluorimetric methods. In all cases the essential oil showed the lowest antioxidant activity, while the aqueous extract showed the highest. This can be explained by the levels of the phenolic compounds in the samples examined. CONCLUSIONS A clear picture of aroma profile of C. glandulosa is presented, and the results obtained differ from those published previously. The high antioxidant potential of C. glandulosa from Croatia was established for the first time. Results from the present study suggest further analysis on this plant species in order to define its medicinal properties.