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.

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.

Ascorbic acid (AA) is a water-soluble vitamin which shows no fluorescence. However, in reaction with iron(III), AA is oxidised to dehydroascorbic acid and iron(III) is reduced to iron(II) which forms a complex with 2,4,6-tripyridyl-S-triazine (TPTZ) in buffered medium. The relative fluorescence intensity of the resulting Fe(TPTZ)22+ complex can be measured at excitation and emission wavelengths of 393 and 790 nm, respectively. Based on this data, a new indirect spectrofluorimetric method for the determination of AA in pharmaceutical samples was proposed. Influence of the reaction conditions, such as acidity of acetic buffer, concentration of TPTZ and iron(III), reaction time and instrumental parameters were investigated in detail. The linear range was from 5.4 × 10−4 to 5.4 × 10−6 mol·L−1 (R = 0.9971). The LOD was 7.7 × 10−7 mol·L−1 and LOQ was 2.3 × 10−4 mol·L−1. Fourteen pharmaceutical samples containing various amounts of AA were analysed. Influences of potential interfering substances were also examined. Analysis of commercial pharmaceutical formulations showed good correlation with the nominal values given by the manufacturers and with the results obtained by a titration method. The proposed method can be applied in routine quality control in the pharmaceutical industry due to its sensitivity, simplicity, selectivity and low cost.

UDK 582.711.714:577.164.2           543.42:577.164.2 Vitamin C or ascorbic acid content has been determinated by spectrophotometric method and titrimetric method in flowers of some Bosnian hawthorns (Crataegus L). species. Spectrophotometric method used in this study was based on the kinetic reaction between Vitamin C and methylene blue. Measurements were carried out at absorption maximum, λmax= 665 nm. We found that the lowest content of vitamin C was 617.07 mg/100 g of dry sample in flowers of the C. microphylla, and the highest level of Vitamin C was found in the C. monogyna (1104 mg/100 g of dry sample) flowers. Recoveries of the results obtained by the spectrophotometric method were 94 % - 100% with relative standard deviation (RSD) values from 4.5% – 6.7 %. Obtained results shown that flowers of investigated Crataegus L. species are good source of vitamin C.

UDK 577.164.2:582.711.714           535.234:577.164.2 Vitamin C or ascorbic acid content has been determined by spectrophotometric method in fruits of some Bosnian hawthorns (Crataegus L). species. Spectrophotometric method used in this study is based on the kinetic reaction between Vitamin C and methylene blue. Measurements were carried out at absorption maximum, λmax= 665 nm. Titrimetric method was used as the reference method for comparison of the obtained results. We found that the lowest content of vitamin C was 106.12 mg/100 g of a dry sample in fruits of the C. monogyna, and the highest level of Vitamin C was found in the C. microphylla (231.96 mg/100 g of a dry sample) fruits. Recoveries of the results obtained by the spectrophotometric method were 101.4% - 108.0% with relative standard deviation (RSD) values ranging between 0.40% - 3.37%. Obtained results showed that fruits of studied Crataegus L. species are a good source of vitamin C with its potential to be used in food industry as the natural antioxidant.

UDK 631.4:546.19 A simple and inexpensive method for the determination of inorganic As(III) and As(V) at low ppb levels was developed. The method is based on formation of hydride from a sample solution and its reaction with mercury bromide on a solid support. Formation of a yellow-brownish product was optically detected. Amidosulfonic acid was used as a reaction medium for determination of total inorganic arsenic, while citrate buffer (0.1 mol/dm3, pH=5.5) was used as a reaction media for determination of As(III) alone. As(V) was calculated as a difference of total inorganic arsenic and As(III). This method has been applied to soil extracts. Extraction of inorganic arsenic from soil samples was done in three-step sequential extraction with the following extractants: NH4H2PO4 (0.05 mol/dm3); NH4-oxalate buffer (0.2 mol/dm3, pH=3.25); and mixture of NH4-oxalate buffer (0.2 mol/dm3) and ascorbic acid (0.1 mol/dm3) at pH=3.25. The method was suitable for determination of inorganic arsenic species in soil extracts covering concentration range of the analyte between 0.2 - 20 ppb.