The chemical composition and antioxidant properties of the essential oil and EtOH extract of immortelle (Helichrysum italicum (Roth) G.Don subsp. italicum, Asteraceae) collected in Montenegro were evaluated. The essential oil was characterized by GC/MS analysis, and the content of total phenolics and flavonoids in the EtOH extract was determined using the FolinCiocalteu reagent. The free-radical-scavenging capacity (RSC) of both the essential oil and the EtOH extract was assessed with the 2,2-diphenyl-1-pycrylhydrazyl (DPPH) method. Moreover, the inhibition of hydroxyl radical ((.) OH) generation by the EtOH extract of immortelle was evaluated for the first time here. Neryl acetate (28.2%) and γ-curcumene (18.8%) were the main compounds in the essential oil, followed by neryl propionate (9.1%) and ar-curcumene (8.3%). The chemical composition of the oils of the examined and additional 16 selected Helichrysum italicum taxa described in literature were compared using principal component (PCA) and cluster (CA) analyses. The results of the statistical analyses implied the occurrence of at least four different main and three subchemotypes of essential oils. Considering the antioxidant properties, the EtOH extract of immortelle exhibited similar potential as propyl gallate and quercetin, while the essential oil exhibited relatively weak DPPH(.) -scavenging capacity.

Caffeine is odorless, bitter taste substance which can be naturally found in coffee, cocoa, tea leaves, and is intentionally added in food and pharmaceutical products. It can also be found in surface water in small concentrations where is often used as an excellent indicator of human waste. The aim of the work is determination of caffeine content in food, beverages, analgesics and surface water using solidphase extraction followed by high-performance liquid chromatography (HPLC). Caffeine content was determined in 12 commercial tea and coffee products, non-alcoholic energy drinks and food, 5 combined preparations of analgesics and the Danube samples collected from 7 representative locations. The results showed that caffeine content in food ranged 5,6-158 mg/100 g, tea samples 24,71-30,81 mg/100 ml, coffee samples 1328-3594 mg/100 g, energy drinks 9,69-30,79 mg/100 ml and in the Danube samples 15,91-306,12 ng/l. Caffeine content in combined commercial formulations of non-narcotic analgesics of all brands did meet specifications. The data suggested that the proposed HPLC method can be used for routine determination and control of caffeine content in different matrices.

Background/Aim. Tea and coffee are one of the most widely consumed beverages in the world due to their beneficial health effects which are largely associated with their phenolic compounds composition, including chlorogenic acid. The main aim of this study was to determine 5-caffeoylquinic acid (5-CQA), as one of the major classes of chlorogenic acid, in various commercial tea and coffee samples present at the Serbian market. Methods. A high-performance liquid chromatography (HPLC) method for determination of 5-CQA in plant extracts was applied to determine the content of this active compound in commercial tea and coffee samples. Mobile phase was aqueous 1.5% acetic acid - methanol (80:20, v/v) with the flow rate of 0.8 mL/min. Run time was 15 min and column temperature 25?C. The detection was performed at 240 nm. Results. The HPLC method was modified and revalidated. The 5-CQA content varied depending on the type of tea (white, green, black tea and mate) and the processing technology. Green tea had the highest 5-CQA content (16 mg/100 mL) among the analyzed tea samples. The content of 5-CQA in coffee samples ranged 0-36.20 mg/g of coffee and 0-46.98 mg/100 mL of beverage, showing that the content varied depending on the type of coffee, coffee processing technology and the formulation. Conclusion. The modified and revalidated HPLC method showed a good accuracy, repeatability, selectivity and robustness. The highest amount of 5-CQA was determined in green tea in comparison to white, black and mate tea because the increased oxidation level decreases the amount of 5-CQA. The obtained results for commercial coffee samples indicated that the formulation was the most important factor determining the amount of 5-CQA. It can be concluded that plant material selection, processing conditions and formulation have great influence on the amount of chlorogenic acid (5-CQA) in the final tea and coffee products. [Projekat Ministarstva nauke Republike Srbije, br. OI 172058]