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Cranberry fruit (Vaccinium macrocarpon L., Ericaceae) is a valuable material for the production of juices and other fruit products, quite popular among consumers in Serbia. Different types of cranberry juice are produced in Serbia and other countries, but the chemical composition, as well as the antimicrobial and antioxidant activities of juices depend on both the used technology and the region in which cranberries are grown. Within this study, the screening of bioactive components found in cranberry juice from Serbia was performed by the UHPLC-DAD-MS/MS method, as well as the determination of its antibacterial and antioxidant activities. The juice was obtained by cold-pressing of ripe cranberry fruit grown in Serbia and enriched with sugar. Among the seventeen identified compounds, the most common were phenolic compounds and hexoses, followed by organic acids. The antibacterial activity of the juice was assessed by the disc diffusion method against Listeria monocytogenes, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Salmonella enteritidis, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The DPPH test was used to determine the antioxidant effect. The cold-pressed cranberry juice showed higher antibacterial activity against Gram-positive bacteria. The obtained results will be useful in promoting further progress and development of cranberry cultivation and processing in Serbia.

Five extraction techniques, maceration, reflux, Soxhlet, Tillepape, and ultrasonic extraction, were used to obtain the extractive matter from nettle leaves. The antioxidant activity of extracts was assessed by DPPH, FRAP, and H2O2 test, while the total phenolic and total flavonoid content was determined according to the Folin–Ciocalteu and aluminium chloride methods, respectively. Model Ponomarev and a non-stationary diffusion model through the plant material were used for modelling extraction process. The extract obtained by Soxhlet extraction, containing higher amounts of extractive matter as well as phenolic and flavonoid compounds, showed better antioxidant activity than those obtained by other extraction techniques.

In this work the impact of four different techniques of Clevenger-type hydrodistillation (technique I–IV) on the yield, hydrodistillation kinetics and composition of the essential oils of Anethum graveolens L. seeds was investigated. The highest oil yield, after five consecutive hydrodistillation runs (3.74 ml/100 g of plant material), was achieved by the utilization of filtrated (from plant material) water used in the previous hydrodistillation run plus newly added water in the subsequent runs (technique III). The hydrodistillation of dill seeds took place in two stages: a rapid, early distillation of the oil followed by a much slower second phase. Two kinetics models were successfully used to interpret the hydrodistillation rate of the essential oil of dill. Independent of the technique used, the oil contained the same components but in differing amounts as inferred from detailed gas chromatography–mass spectroscopy (GC–MS) analyses. Carvone was found to be the major component in all obtained oils.

Strawberry is a member of the rose family (Rosaceae, subfamily Rosoideae, tribe Potentilleae) in the genus Fragaria. The cultivated varieties of commercial strawberries usually were designated as Fragaria ananassa. Root, leaf, flower and fruit have the healing properties. The strawberry leaves extract is used for blood cleaning, for treatment of oral inflammation, diarrhea, various gastro-intestinal inflammation, and hemorrhoids, as well as a diuretic. So far, many positive biological effects of strawberries (anticancer, antioxidant and anticoagulant effect) have been proven. The purpose of this study was to evaluate the antioxidant potential of ethanolic extract from cultivated strawberries (Fragariae folium, varieties Senga Sengana) by using different antioxidant assays (DPPH, FRAP, FIC, H2O2 and TBA-MDA). Ethanolic extract from strawberry leaves was obtained by reflux extraction at the boiling temperature. Total phenols and total flavonoids content was determined spectrophotometrically by the method of Folin-Ciocalteu and by method with AlCl3, respectively. In the extract was determined high content of total phenols, while the total flavonoid content is much lower. The concentrations of extract required to neutralize 50% of the initial concentration of DPPH radicals (EC50) after 20 minutes incubation and immediately after adding DPPH radical solution were 7,91 and 19,46 μgcm-3, respectively. Extract was achieved the maximum iron ions chelating ability (67.89%) at a concentration of 2 mgcm-3. Inhibition of lipid peroxidation of 70% was achieved by extract concentration of 0.03125 mgcm-3, while the maximum neutralization of H2O2 (30.47%) was achieved by extract concentration of 0.5 mgcm-3. FRAP value of the investigated extract is 284.51 mgFe/g of dry extract. Presented results of the antioxidant activity show that the obtained extract from the cultivated strawberry leaves is a potential source of natural antioxidants. [Projekat Ministarstva nauke Republike Srbije, br. TR 34012: Biljni i sintetski bioaktivni proizvodi novije generacije]

The essential oils of plants have gained great interest in the pharmaceutical industry due to their biological activities. The objective of the present study was to evaluate the influence of fennel (Foeniculum vulgare Mill.) fruit milling on the essential oil yield, chemical composition and antimicrobial activity. The essential oil was obtained from disintegrated and non-disintegrated fruit by Clevenger-type hydrodistillation with hydromodulus 1:10 m/V during 180 min. The essential oil composition was analyzed using gas chromatography-mass spectrometry (GC–MS) technique combined with flame-chromatographic gas–chromatographic detection (GC-FID). Milling impacted the essential oil yield (3.6 ± 0.3 and 4.0 ± 0.2 g/100 g of plant material from non-disintegrated and disintegrated fruit, respectively), and quantitative, but not qualitative composition of essential oil. Among fourteen identified compounds, the most abundant in essential oil was trans-anethole (64.87 ± 0.07% and 69.89 ± 0.06% from non-disintegrated and disintegrated fruit, respectively). The antimicrobial activity of oil was evaluated using Staphylococcus aureus, Escherichia coli, Proteus vulgaris, Candida albicans, Pseudomonas aeruginosa, Bacillus subtilis, and Klebsiella pneumoniae. The essential oil isolated from disintegrated fruit showed higher antimicrobial activity than the essential oil from non-disintegrated fruit. Among the tested microorganisms, Candida albicans was the most sensitive to the essential oil, followed by Bacillus subtilis.

Polyrotaxanes are intermediary products in the synthesis of topological gels. They are created by inclusion complex formation of hydrophobic linear macromolecules with cyclodextrins or their derivatives. Then, pairs of cyclodextrin molecules with covalently linkage were practically forming the nodes of the semi-flexible polymer network. Such gels are called topological gels and they can absorb huge quantities of water due to the net flexibility allowing the poly(ethylene oxide) chains to slide through the cyclodextrin cavities, without being pulled out altogether. For polyrotaxane formation poly(ethylene oxide) was used like linear macromolecules. There are hydroxyl groups at poly(ethylene oxide) chains, whereby the linking of the voluminous molecules should be made. To avoid the reaction of cyclodextrin OH groups with stoppers, they should be protected by, e.g., acetylation. In this work, the acetylation of the OH groups of β-cyclodextrin was performed by acetic acid anhydride with iodine as the catalyst. The acetylation reaction was assessed by the FTIR and HPLC method. By the HPLC analysis was found that the acetylation was completed in 20 minutes. Inserting of poly(ethylene oxide) with 4000 g/mol molecule mass into acetyl-β-cyclodextrin with 2:1 poly(ethylene oxide) monomer unit to acetyl-β-cyclodextrin ratio was also monitored by FTIR, and it was found that the process was completed in 12 h at the temperature of 10°C. If the process is performed at temperatures above 10°C, or for periods longer than 12 hours, the process of uncontrolled hydrolysis of acetate groups was initiated.

In this review, the biosynthesis of allicin (allyl thiosulfinate) by enzymatic transformation of alliin and various methods of its synthesis with detailed investigation of mechanisms and kinetics are summarized. A convenient method is also described for determination of allicin stability and the utility of the inclusion complexes of this pharmacologically active agent with ?-cyclodextrins in increasing its stability. Allicin is the initial precursor for the production of ajoene ((E)- and (Z)-4,5,9-trithiadodeca- 1,6,11-triene 9-oxides) and vinyldithiin (2-vinyl-4H-1,3-dithiin, and 3-vinyl-4H-1,2- dithiin), which are more stable and show various pharmacological effects. The mechanisms of allicin transformations to these compounds are given in detail. Finally, the data on the pharmacological effects of allicin and its transformation products, ajoene and vinyldithiin, are presented.

The main carriers of the pharmacological activity of garlic (Allium sativum L.) are organic sulfur compounds, the most important among them being allicin, a sulfenic acid thioester, or allylthiosulfonate. In this paper, the identification of synthesized and purified allicin was determined by using various spectroscopic methods (UV/VIS, FTIR, NMR). A HPLC method was developed for the detection and determination of the allicin content. The thermal degradation of allicin by using FTIR method was monitored. The method for the production of allicin gel based on Carbopol 940 (poly(acrylic acid)) was elaborated. The antimicrobial activity of pure allicin and allicin incorporated into gel by using a disk diffusion method was determined. In order to determine the antioxidant activity of allicin DPPH test was done and it was proved that with low concentrations (1 mgcm-3) a high DPPH radicals scavenging capacity (90%) was achieved.

Allicin is the most biologically active substance present in garlic. It can be synthesized or obtained by extraction of fresh garlic. Transformation products of allicin are also biologically active. The aim of this study was to examine the antioxidant activity of synthesized allicin and its transformation products obtained using microwaves in methanol at 55 °C as well as their effect on HeLa cells growth. The antioxidant activity was determined by DPPH (2,2-diphenyl-1-picrylhydrazyl radical) test. The effect on HeLa cells growth was determined by MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) test. For MTT test, allicin and its transformation products were dispersed in carmellose sodium solution and examined in concentrations ranging from 0.3 μg/mL to 3 mg/mL. Allicin showed stronger antioxidant activity than the transformation products. A maximum degree of neutralization of DPPH radicals, about 90%, was reached when the concentration of allicin was 2 mg/mL, with an EC50 (concentration of sample which is required for reduction of the initial concentration DPPH radicals to 50%) value of 0.37 mg/mL. In our study, allicin and its transformation products were not cytotoxic to HeLa cells under the examined conditions. The highest concentration of allicin and its transformation products had a slight antiproliferative effect, with a more pronounced effect of allicin, which reflected on the morphology of HeLa cells. The examined substances are safe to use on epithelial cells at concentrations up to 3 mg/mL when applied in carmellose sodium solution. Using carmellose sodium as a dispersing agent could be recommended as a good approach for testing liposoluble substances in liquid cell cultures.

In this review, the biosynthesis of allicin (allyl thiosulfinate) by enzymatic transformation of alliin and various methods of its synthesis with detailed investigation of mechanisms and kinetics are summarized. A convenient method is also described for determination of allicin stability and the utility of the inclusion complexes of this pharmacologically active agent with β-cyclodextrins in increasing its stability. Allicin is the initial precursor for the production of ajoene ((E)- and (Z)-4,5,9-trithiadodeca- 1,6,11-triene 9-oxides) and vinyldithiin (2-vinyl-4H-1,3-dithiin, and 3-vinyl-4H-1,2- dithiin), which are more stable and show various pharmacological effects. The mechanisms of allicin transformations to these compounds are given in detail. Finally, the data on the pharmacological effects of allicin and its transformation products, ajoene and vinyldithiin, are presented.