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In this study, the antimicrobial efficacy of a cloud-point extract (CPE) derived from the peels of horned melon (Cucumis metuliferus) was evaluated. By employing cloud-point extraction, a cutting-edge extraction technique, bioactive phytochemicals were effectively isolated from the peels, yielding a rich concentration of antioxidants and antimicrobial agents. The antifungal activities of the extract, including growth inhibition, minimal inhibitory concentration (MIC), and time-kill kinetics, were tested against phytopathogenic fungal species isolated from fruits, namely Aspergillus sp., Penicillium sp., Trichoderma sp., and Geotrichum sp. The extract exhibited notable antimicrobial properties, with inhibition zones measuring between 16 and 31 mm, and MIC values ranging from 3.75 to 60 mg/mL. High-performance liquid chromatography (HPLC) analysis identified several phenolic compounds within the CPE, including p-hydroxybenzoic acid, gallic acid, protocatechuic acid, caffeic acid, catechin, syringic acid, and vanillic acid. These findings suggest that the CPE of horned melon peels holds noteworthy promise as a natural antimicrobial agent, with potential applications in food preservation and safety. Furthermore, this research indicates the potential of suppressing fungal growth on fresh fruit samples as well, since the work included monitoring the development of fungal contamination on grape samples coated with CPE extract, encouraging the sustainable extraction and application of natural bioactive compounds.

In this study freeze-drying and oven-drying (at 50 and 65 °C) were applied for the preparation of dried pumpkin waste. The effect of drying methods on physical properties (moisture content, water activity, hygroscopicity, water solubility, bulk and tapped density, flowability and colour), content of bioactive compounds (carotenoids and phenolics) and antioxidant activity were investigated. Also, the influence of one-year storage at –20 °C on the bioactive compounds content and the antioxidant activity of dried pumpkin waste was examined. Results indicated that drying method showed a significant impact on the investigated characteristics. Bioactive compounds content and antioxidant activity by DPPH test of freeze-dried were higher than of oven-dried pumpkin waste, while higher antioxidant activity in reducing power assay was determined by oven-dried pumpkin waste. An artificial neural network model was developed, for the anticipation of antioxidant activity according to bioactive compounds content (phenolics and carotenoids), in oven-dried (at 50 and 65 °C) and in freeze-dried pumpkin waste after one-year storage. These models showed good prediction properties (the r2 value during training cycle for output variables was 0.999). It was demonstrated that pumpkin waste is potentially an important source of bioactive compounds, which can be used after extraction in suitable forms in the development of functional food products.

The application of bioactive antioxidant compounds is limited because of their instability. To overcome this drawback, different protection systems including encapsulation have been developed. In this study, for the stabilisation of bioactive compounds (carotenoids and phenolics) extracted from tomato waste, encapsulation with carbohydrate (inulin and gum arabica) and protein (soy protein and pea protein) wall materials by freeze drying method was applied. Content of bioactive compounds and antioxidant properties (determined by DPPH, reducing power and β-carotene bleaching assay) of encapsulates before and after in vitro digestion was investigated. Also, in obtained encapsulates carotenoid stability during storage at ambient (25 ± 5 °C) light and dark conditions for four weeks was assessed. The results indicated that release behavior of bioactive compounds and antioxidant activity after digestion of encapsulates varied according to the type of wall material. Protein carriers showed better ability to preserve phenolic compounds through in vitro gastrointestinal digestion in comparison to carbohydrate wall materials. Pea protein showed best carrier properties for delivery of carotenoids, while differently to other used carriers, gum arabica showed minor ability to release carotenoids after in vitro gastrointestinal digestion. During storage higher content of carotenoids was preserved in encapsulates prepared with carbohydrate carriers. All encapsulates retained higher amount of carotenoids under dark conditions. The results of this study showed that assessment of the behavior of encapsulates during digestion and storage is necessary in order of selection appropriate delivery system of bioactive compounds in powder form which can be used as ingredient in functional food products.

Utilization of carotenoids as a nutraceutical ingredients or natural colorants within foods is currently limited due to their instability. Encapsulation is one of the prominent means used to improve carotenoid stability. In this study the content of bioactive compounds (lycopene, β-carotene and phenolics) and antioxidant activity (DPPH, ABTS, superoxide anion and reducing power test) were investigated in the tomato waste extract. Based on the obtained results, tomato waste showed high contents of lycopene (13.72 mg/100 g DW), β-carotene (12.36 mg/100 g DW) and phenolic compounds (203.33 mg/100 g DW). Also, high values of antioxidant activity were determined in all applied tests. To protect extracted sensitive carotenoid compounds (lycopene and β-carotene) tomato waste extract was encapsulated with various encapsulating materials (soy protein, pea protein, inulin and gum arabica) by freeze drying method. The influence of applying different encapsulating materials on the encapsulation efficiency of carotenoids (lycopene and β-carotene) was studied. Also, obtained encapsulates were characterized in terms of water activity, moisture content, hygroscopicity, flowability, density ratios and particles size. Encapsulate on the basis of gum arabic showed highest encapsulation efficiency of β-carotene (53.47%), while encapsulate prepared with soy protein as encapsulating material showed highest encapsulation efficiency of lycopene (51.44%). The results of this study support the need for preparation of encapsulates with different encapsulating material and evaluation of their characteristics with the aim of development powder forms suitable for supplementation and food fortification.

Carrot is an important root vegetable rich in bioactive compounds like carotenoids and polyphenols with appreciable levels of several other functional components having significant health-promoting properties. Utilization of carotenoids is limited due to their instability. Encapsulation is one of the alternatives used to improve carotenoid stability. The objectives of this study were to optimize the extraction and encapsulation of carotenoids from carrot. Freeze-dried carrots were extracted by conventional solvent extraction (CSE) using four solvents, i.e. ethanol, acetone, ethyl acetate, and hexane. Although CSE using hexane and ethyl acetate resulted in highest carotenoid contents (18.27 and 15.73 mg β-carotene/100 g), acetone and ethanol at a solid to solvent ratio 1:10 w/v with slightly lower carotenoid contents (14.52 and 11.45 mg β-carotene/100 g) were chosen for further studies due to their higher food compatibility and higher polyphenol content (88.86 and 66.21 mg GAE/100 g) than with lower solid to solvent ratio (1:5 w/v). Ethanol and acetone carrot extracts were encapsulated using different carriers by a freeze-drying method in order to obtain the optimum encapsulate with the highest carotenoid encapsulation efficiency (EE). Encapsulation using the maltodextrin, whey and soy protein as a wall material yielded an EE of carotenoids ranging from 41.95% to 100%. The encapsulated β-carotene content was evaluated during two months of storage at ambient temperature under light and dark conditions. Generally, the retention of carotenoids was significantly higher in dark conditions, where maximum retention (65.94-87.32%) occurred in the samples encapsulated in maltodextrin and soy protein. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 31044]

Sprouts of cereals have received significant attention as functional food due to their nutritional and functional value. Consumption of sprouts has become increasingly popular among people interested in improving and maintaining their health status by changing dietary habits. Cereal grains contain several classes of phytochemicals, i.e. phenolics, chlorophylls, and carotenoids. However, their nutritional and chemical profile is altered and improved during germination. The purpose of this study was to find the best ratio of the powdered wheat (WS), oat (OS) and barley (BS) sprouts for designing the cereal sprout mixture (CSM) with the highest total phenolic content (TPh) and antioxidant capacity (AC), using Simplex-Centroid experimental design and response surface methodology (RSM). Single- and multi-response optimizations showed that OS did not contribute to TPh or AC values of CSM and, therefore, was not included in any of the compositions of the optimized CSM. Single-response optimizations showed that the highest TPh was found for CSM containing 82% BS and 18% WS, while the best AC was found for pure BS. The predicted ratio of cereal sprout powders in CSM obtained by multi-response optimization was: 96% BS and 4% WS. This mixture possessed the highest predicted TPh and AC (372.32 mg GAE/100 g, 549.99 μmol TE/100 g, respectively), which was confirmed to be in accordance with the experimental values. Based on the results obtained in this study, a designed CSM is proposed as a convenient ingredient of functional food products, dietary supplements and nutraceuticals.

Samples of three types of honey: polyfloral (PH), linden (LH) and acacia (AH,) without and with addition of dried cherries (40%) were analyzed before and after three months of storage. The total phenol (TPh), flavonoid (TFd) and anthocyanin (TAn) contents, antioxidant activities and sensory properties of honeys with and without the addition of dry cherries were evaluated. TPh and TFd increased with addition of dried cherries to the honey, while enriched honeys showed high TAn. The LH sample with dried cherries showed the highest anthocyanins content (41.41mgCGE/100g). The antioxidant activity increased with addition of dried cherries in honey in the DPPH• test and reducing power. The PH and enriched PH exibited the best antiradical activity compared to LH and AH. The EC50 DPPH values were: 23.81 for PH and 24.19 mg/mL for PH, while the EC50 DPPH were: 1.16 mg/mL for PH40 and 1.18 mg/mL for PH40s. RP0.5 values were: 57.00 mg/mL for PH40 and 56.00 mg/ml for PH40s, while RP0.5 were: 15.05 mg/mL for PH40 and 15.18 mg/mL for PH40s. The statistical analysis showed that TPh, TFd and TAn, and antioxidant activity of honeys and enriched honeys showed significant correlation. Sensory analysis of honey with dried cherries, before and after storage, indicated very good sensory characteristics.

The production of high-quality freeze-dried raspberry was studied by response surface method. Two independent variables, temperature (X1) and time (X2) were determined as the most important factors affecting the final product quality estimated by the responses: total phenol (Y1), total anthocyanin (Y2), vitamin C (Y3) and total bioactive compounds (Y4) content. A two-factor central composite design was used for freeze-drying experiments. The second order polynomial models obtained were found to be significant (p

Dried apricot was extracted using two different solvents: 80% ethanol and hexane. The contents of total phenolics, flavonoids and anthocyanins were determined in ethanol apricot extract (EAE), while the carotenoid content was determined in hexane apricot extracts (HAE) by spectrophotometric method. The detected amounts of bioactive compounds in dried apricot were: phenolics 498.13 ± 12.04 mg GAE/100g DA, flavonoids 218.45 ± 14.14 mg R/100g DA and anthocyanins 3.08 ± 0.40 mg CGE/100g DA. In dried apricot the β-carotene was present in the amount of 0.56 ± 0.03 mg/100g DA. Some individual phenolic compounds in EAE were determined by HPLC analysis and the most dominant compound was gallic acid (35.02 ± 1.65 mg/100g DA). Free radical scavenging activities of EAE and HAE were tested spectrophotometrically using stable DPPH radicals and reducing power method. The EC50 value for EAE was 2.05 ± 0.06 mg/ml and for HAE was 6.28 ± 0.01 mg/ml. The RP0.5 values determined by reducing power method were 6.11 ± 0.01 mg/ml for EAE and 62.04 ± 0.03 mg/ml for HAE. The results indicate that dried apricot can be a valuable source of natural antioxidants and can be used as a functional food ingredient in the food industry.

In this study, lipophilic tomato waste extracts (obtained from the Knjaz, Bačka, Saint Pierre, Rutgers and Novosadski niski genotypes) were analyzed to determine their lycopene and β-carotene content, as well as their kinetics of antiradical activity. The kinetic behaviour of lipophilic tomato waste extracts and standard antioxidant compound (BHA) were investigated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical test. In addition, correlations between the contents of lycopene and β-carotene content and antiradical activity of lipophilic tomato waste extracts were also sought. The content of lycopene in tomato waste extracts ranged from 4.29 ± 0.14 mg/g for Rutgers waste exract to 22.64 ± 0.86 mg/g for Knjaz waste extract, while the content of β-carotene varied from 2.48 ± 0.09 mg/g for Novosadski niski waste exract to 15.93 ± 0.56 mg/g for Knjaz waste extract. Based on the time required for the DPPH radical-extract reaction to reach steady state, the investigated lipophilic extracts, as well as BHA can be classified as the antioxidants with slow (steady state ≥ 150 min) antiradical behaviour. A comparison of the efficient concentrations at different kinetic times (EC50,t) for the lipophilic tomato waste extracts and BHA showed that the DPPH antiradical activity decreased in the order of BHA > Knjaz > Bačka > Saint Pierre > Rutgers > Novosadski niski. The results of the correlation analysis suggest that lycopene is the main individual carotenoid responsible for the EC50,t values of the tomato waste extracts towards the stable DPPH radical. [Projekat Ministarstva nauke Republike Srbije, br. TR 31044]

The main chemical composition, contents of total phenolic (TPh), total flavonoid (TF), and total monomeric anthocyianin (TMA), as well as the antioxidant activity of two raspberry cultivars (Meeker and Willamette), two blackberry cultivars (Čačanska bestrna and Thornfree) and wild bilberry were studied. The raspberry cultivars had the highest total solids among fruits investigated. Bilberry fruits had the highest sugar-to-acid ratio. Blackberry fruits were richer in crude fibers (cellulose) in comparison to raspberry and bilberry fruits. The content of pectic substances was highest in the bilberry. Also, bilberry had a highest content of TPh (808.12 mg GAE/100 g FW), TF (716.31 mg RE/100 g FW) and TMA (447.83 mg CGE/100 g FW). The antioxidant activity was evaluated spectrophotometrically, using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity assay. The DPPH free radical scavenging activity, expressed as the EC50 value (in mg of fresh weight of berry fruit per ml of the reaction mixture), of bilberry (0.3157 ± 0.0145 mg/ml) was the highest. These results also showed that the antioxidant value of 100 g FW bilberry, raspberry - Willamette, raspberry - Meeker, blackberry - Čačanska bestrna and blackberry - Thornfree is equivalent to 576.50 mg, 282.74 mg, 191.58 mg, 222.28 mg and 272.01 mg of vitamin C, respectively. There was a significant positive correlation between the antioxidant activities and content of total phenolics (RTPh 2=0.9627), flavonoids (RTF 2=0.9598) and anthocyanins (RTMA 2=0.9496) in berry fruits. [Projekat Ministarstva nauke Republike Srbije, br. TR 31044]

The changes in total phenol and flavonoid content, as well as antioxidant activity was monitored in acacia honey supplemented with prunes in 20, 30 and 40% mass concentrations. The total phenolic content increased by 2.5 times (from 16.18 to 41.64 mg GAE/100 g) with increasing concentration of prunes in honey, while the increase in flavonoid content was even higher, approximately 11.5-fold (from 2.65 to 30.86 mg RE/100 g). The addition of prunes also improved the antioxidant activity of acacia honey. The honey samples with highest content of prunes, 40%, exhibited the best antioxidant activity measured by hydroxyl radical sacvenging assay (EC50 •OH=4.56 mg/ml), 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay (EC50 DPPH=16.48 mg/ml), and reducing power (EC50 RP=81.17 mg/ml). Judging from the high correlation coefficients, ranging from 0.771 to 0.947 for total phenolics, and from 0.862 to 0.993 for total flavonoids, it is obvious that these compounds were associated with the antioxidant mechanisms. On the other hand, sensorial properties of supplemented honeys were lower than that of pure acacia honey, where flavor of supplemented honey was the least affected. Our results indicate that the supplementation of honey with prunes improves antioxidant activity of honey by enriching the phenolic composition, with slight modifications in sensorial characteristics.

The kinetic behaviour of tomato waste extracts (obtained from six genotypes) and standard antioxidant compounds (ascorbic and caffeic acid) were investigated using 2,2-diphenyl-1-picrylhydrazyl radical test. Based on the time needed for the reaction to reach steady state, the investigated extracts show very slow (steady state ≥ 180 min) antiradical behaviour, ascorbic acid act as rapid antioxidant (steady state < 5min) while caffeic acid is rapidintermediate antioxidant (5 min < steady state < 20 min). The efficient concentrations at different kinetic times EC50,t were determined for all extracts, ascorbic and caffeic acid. EC50,t was used as a parameter to screen and compare antiradical activities of food extracts with slow kinetic action. Irrespective of the time considered, the comparison of the EC50,t for extracts showed that the DPPH radicals scavenging activity of extracts decreased in the order of O2 > Knjaz > Bačka > Saint Pierre > Rutgers > Novosadski niski. Tomato waste extracts showed very slow kinetic action, which is probably result of the different kinetic bevaviour of phenolic compounds, present in tomato waste, as well as other antioxidants (vitamins, carotenoids etc).

The macro- and micro-chemical composition, as well as antioxidant activity of two strawberry cultivars, Marmolada and Clery, were studied. Results showed a noticeable difference in the sugar, protein and pectin contents. Clery had 6.92% and Marmolada 4.93% of total sugar. Also, protein and pectin contents were higher in the Clery cultivar. No significant difference was observed in acidity, as well as in ash and cellulose content. Marmolada had a higher content of total phenolics and flavonoids (228.04 mg GAE /100 g FW and 136.01 mg RE/100 g FW, respectively ). The anthocyanins content in Marmolada (32.0 mg CGE/100 g FW) was slightly lower than in Clery (36.0 mg CGE/100 g FW). The antioxidant activity was evaluated spectrophotometrically, using 2,2-diphenyl- 1-picrylhydrazyl (DPPH) radical scavenging activity assay. The DPPH free radical scavenging activity, expressed as EC50 value, of Marmolada (0.77 mg/ml )was higher than of Clery (0.83 mg/ml). There was a significant positive correlation (R2>0.90) between the concentration of phenolics/flavonoids/anthocyanins and DPPH radical scavenging activity of both strawberry cultivars. These results also showed that the antioxidant value of 100 g FW Marmolada and Clery is equivalent to 237.91 mg and 219.01 mg of vitamin C, respectively.

Four berry (bilberry, blackberry, strawberry and raspberry) fruits pomace, a waste product coming from juice production, were extracted with 80% methanol containing 0.05% acetic acid. The highest content of antioxidant components, total polyphenols, flavonoids and anthocyanins, was found in the bilberry pomace extract (1116.24, 1047.39 and 1279.49 mg/100g fresh pomace, respectively). The antioxidant activity of the four berry pomace extracts (BPE) was determined using DPPH free radical scavenging assay and reducing power. There was a high linear correlation between the IC50 and content of anthocyanins (r2=0.98) and polyphenols (r2=0.85). Also, a good correlation was found between the IC50 and the content of flavonoids. The strawberry pomace extract showed the highest (RP0.5=0.35 mg/ml), while the blackberry pomace extract showed the lowest (RP0.5=0.57 mg/ml) reducing power. The results showed that BPE can be a valuable source of natural ingrediences of the products in the food, cosmetical and pharmaceutical industry.

In this study, three Serbian honey samples (Acacia, Linden and "Homoljski med") were analyzed to determine their total phenolic, flavonoid and antioxidant content, as well as their in vitro antioxidant activity. The antioxidant activity of honeys was examined by different tests, including the reducing power and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. In addition, correlations between the antioxidant activity and total phenolic, as well as flavonoid content were also sought. The highest content of total phenolics (27.44 mg/100 g), flavonoids (9.78 mg/100 g), reducing power and DPPH free radical scavenging activity were obtained in the case of Linden honey. The EC50 values of the Linden honey, determined based on the reducing power and DPPH radical scavenging activity, were 24.17 mg/ml and 51.34 mg/ml, respectively. Also, the antioxidant content was highest for Linden honey, and it valued 5.45 mg QEAC/100 g (expressed as mg of quercetin equivalent antioxidant content - QEAC per 100 g of honey) and 7.82 mg AEAC/100 g (expressed as mg of ascorbic acid equivalent antioxidant content - AEAC per 100 g of honey). Also, a linear correlation was observed between the antioxidant activity and total phenolics, as well as total flavonoids.

Mandarin peel, a waste product coming from juice production, was extracted by conventional extraction with 70% acetone. Content of flavonoids in mandarin peel extract (MPE) was determined by HPLC. Hesperidin was the most dominant flavonoid. Free radical scavenging activity of MPE on stable DPPH radicals and reactive hydroxyl radicals was also evaluated. EC50 value determined in spectrophotometrical DPPH radical assay was 0.179 mg/ml, while this value in ESR spin trapping hydroxyl radical assay was 0.415 mg/ml. Also, MPE showed protective effects in stabilising sunflower oil during accelerated storage. The results indicated that mandarin peel can be a valuable source of natural antioxidants.

This study is concerned with the effects of two extraction procedures (using ultrasonic bath and high performance homogenizer) on the extraction efficiency of polyphenolics present in the tomato waste. The isolation of flavonoid fraction of obtained extracts was performed by solid-phase extraction. The antioxidant activity of flavonoid fractions was determined using different spectrophotometric tests, including reducing power and 2,2- diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assays. The content of total polyphenolics and flavonoids in extract obtained employing homogenizer (E2) was higher than in the extract obtained employing ultrasonic bath (E1), and it was 14.33 mg/g and 7.70 mg/g, respectively. The flavonoid fraction (EF2) of extract E2 showed higher antioxidant activity than flavonoid fraction (EF1) of extract E1. The DPPH free radical scavenging activity of fractions EF1 and EF2, expressed as EC50 value, were 0.78 mg/ml and 0.45 mg/ml, respectively. The obtained results show that tomato wastes can be used as an easily accessible source of antioxidant polyphenolics.

Composition and antioxidant activity of grape seed extract (GSE) obtained from red grape varietes are very well documented, in contrast to the white varietes. This paper presents the results of polyphenols content of ethyl acetate extract of grape seeds, obtained from two white grape varieties, Italian Riesling and Župljanka, and their antioxidant activity on the stable DPPH radical. The influence of the addition of GSE to raspberry juice on the DPPH radical was also examined. Content of total polyphenols in GSEs ranged between 81.6 and 82.8% (w/w), and the contetn of flavan-3-ols between 66.2 and 91.0% (w/w). HPLC results showed that the most abundant components in the extract were (+)-catechin and (-)-epicatechin for both grape varieties. All tested GSEs exhibited good antioxidant activity. IC50 values for the GSEs of Italian Riesling and Župljanka were 0.79 and 0.95 mg sample/mg DPPH radical, respectivelly. Since the GSE of Italian Riesling possesed stronger antioxidant activity, it was used for further experiments. The IC50 value for raspberry juice was 4.18 mg raspberry juice/mg DPPH. The raspberry juice with addition of 0.60 μg/mL of GSE showed antioxidant activity of 39.2%. The same juice with the threefold concentration of vitamin C (1.81 μg/ml) exhibited similar antioxidant activity (33.9%). Antioxidant activity of the same amount of juice without added antioxidants was lower (15.7%). The results showed that the GSE of white varietes could be considered as a good functional food ingredient.

Granny Smith apple pomace was subjected to evaluation as valuable source of antioxidant and anticancer phytochemicals on the basis of its content in phenolic compounds, antioxidant and antiproliferative activity. The total cotent of phenolics, flavonoids and flavan-3-ols in apple pomace determined spectrophotometrically, was 7.02 mg/g, 0.51 mg/g and 8.80 mg/g. Major phenolics (phenolic acids, flavan-3-ols, flavonoids and dihydrochalcons) in apple pomace were identified and quantified by HPLC. The antioxidant activity of apple pomace on stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) and reactive hydroxyl radicals, was investigated by electron spin resonance (ESR) spectroscopy. The IC50 DPPH and IC50 OH values of Granny Smith apple pomace were 9.51 mg/ml and 29.17 mg/ml, respectively. The antiproliferative activities of apple pomace on cervix epitheloid carcinoma (HeLa), colon adenocarcinoma (HT-29) and breast adenocarcinoma (MCF7) cell lines were determined according to the MTT (3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide) colorimetric assay. The IC50 HeLa , IC50 HT-29 and IC50 MCF7 values of Granny Smith apple pomace were 26.40 mg/ml, 22.47 mg/ml and 21.26 mg/ml, respectively. The significant correlations between antioxidant activities and antiproliferative activities were established (p

This study is concerned with the fractionation and determination of major antioxidant compounds (phenols, flavonoids, anthocyanins and vitamin C) in commercial cranberry extract. The total content of phenolics, flavonoids and total and monomers of anthocyanins, determined spectrophotometrically, was 1.67 mg/g, 0.41 mg/g, 5.12 mg/g and 3.32 mg/g. The content of vitamin C, determined volumetrically, was 121.74 mg/g. Commercial cranberry extract was dissolved in 80 % acetone and the solution was fractionated using solid phase extraction (SPE) in order to abstract vitamin C, neutral and acidic phenols. The free radical scavenging activity of the cranberry extract and its fractions was investigated on stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) and reactive hydroxyl radicals employing electron spin resonance (ESR) spectroscopy. The most effective fractions were those containing vitamin C (AADPPH= AAOH=100%), neutral (AADPPH=89.50% and AAOH=43.11%) and acidic (AADPPH=83.98% and AAOH=38.58%) phenols. The presence of vitamin C, abstracted from cranberry extract, was determined by Fe(III)-mediated ascorbate oxidation which yields characteristic ESR doublet spectrum of ascorbyl radical.

The influence of extracts of cranbeny fruit and mixed tea (containing 40% cranberry) on stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals has been investigated by electron spin resonance (ESR) spectroscopy. All investigated extracts possess very high antioxidant activity, which increased dose-dependently at mass concentrations ranging from 0.5 to 3.5 mg/ml. The high contents of phenolic s (3.60-4.52 mg/g), anthocyanins (0.23-1.52 mg/g), flavan-3-ols (1.25-3.05 mg/g) and vitamin C (0.07-0.15 mg/g) in investigated extracts indicated that these compounds significantly contributed to the antioxidant activity. All these results show that the extracts of cranberry fruit and mixed tea can be used as easily accessible source of natural antioxidants and as a possible food supplement.

Different concentrations ofmethanol aqueous solution with or without 0.5% acetic acid and 80% acetone were used to achieve the highest yield of extraction of phenolics from Induna apple pomace. The highest content of phenolics (6.38 mg/g) was detected in the 80% methanol extract. The influence of 80% methanol extract of Induna apple pomace on stable l,l-diphenyl-2-picrylhydrazyl (DPPH) and reactive hydroxyl radicals has been investigated by electron spin resonance (ESR) spectroscopy. Based on the obtained results it can be concluded that the investigated extract is more effective in the DPPH test than on the DMPO-OH scavenging. In both cases antioxidant activity increased with increasing concentration of the investigated extract. The high contents ofphenolics (6.38 mg/g), flavonoids (1.01 mg/g) and flavan-3-ols (0.70 mg/g) in 80% methanol extract indicated that these compounds contributed to the antioxidant activity of Induna apple pomace.

Zinc(II) chloride reacts with 2-methylbenzimidazole derivatives to give complexes of the formula ZnL2Cl2-nH2O, where L=2-methylbenzimidazole l-benzyl-2-methylbenzimida-zole and l-(4-methylbenzyl)-2-methylbenzimidazole n=0, 0.5 or 1. All the ligands and their zinc(II) complexes were evaluated for their in vitro antimicrobial activity against Pseudomonas aeruginosa Bacillus sp., Staphylococcus aureus, Sarcina lutea and Candida pseudotropicalis. It was found that the majority of the investigated compounds displayed in vitro antimicrobial activity against very persistent microorganisms, except for the starting ligand, 2-methylbenzimidazole and its zinc(II) complex which were active only against gram-negative bacteria. None of the compounds was significantly effective against Candida pseudotropicalis, except for l-(4-methylbenzyl)-2-methylbenzimidazoleandits complex, which very slightly or slightly inhibited the yeast growth. The minimum inhibitory concentration (MIC) was determined for all the ligands and their complexes. The effect of ligand and complex structure on the antimicrobial activity was discussed.

The methanol, petroleum ether, chloroform, ethyl acetate, 1-butanol and water extracts were obtained by extraction of mountain germander (Teucrium montanum L). The total phenolic content in extracts was measured by Folin-Ciocalteu method. The 1-butanol extract had the highest phenolic content (296.00 mg/g). High performance liquid chromatography (HPLC) was employed to define qualitative and quantitative content of phenolic acids in mountain germander extracts. The largest number of phenolic acids were determined in ethyl acetate and 1-butanol extracts, while these acids were not present in petroleum ether extract. The highest content of phenolic acids (28.619 mg/g) had ethyl acetate extract and gentisic acid (14.432 mg/g) was its major component. Despite of a large number of phenolic acids in 1-butanol extract their content was only 3.740 mg/g.

Cobalt(II) chloride reacts with 2-aminobenzimidazole derivatives to give complexes of the formula [CoL2Cl2], where L=2-aminobenzimidazole 1-benzyl-2-aminobenzimidazole and 1-(4-methylbenzyl)-2-aminobenzimidazole. All the ligands and their cobalt(II) complexes were evaluated for their in vitro antimicrobial activity against Pseudomonas aeruginosa, Bacillus sp. Staphylococcus aureus, Sarcina lutea and Saccharomyces cerevisiae. The minimum inhibitory concentration (MIC) was determined for all ligands and their complexes. It was found that tested compounds were more active against gram-positive than gram-negative bacteria. None of the compounds were significantly effective against yeast Saccharomyces cerevisiae, except 2-aminobenzimidazole complex, which moderately inhibited the growth of yeast. 1-(4-methylbenzil)-2-aminobenzimidazole was found to be slightly active against Saccharomyces cerevisiae. The same ligand showed the lowest MIC value of 60 (g/ml against Pseudomonas aeruginosa, as well as 125 (g/ml, against Bacillus sp. and Sarcina lutea. The MIC value of its cobalt(II) complex was 60 (g/ml against Pseudomonas aeruginosa. Cobalt(II) complex with 1-benzyl-2-aminobenzimidazole showed the lowest MIC value of 60 (g/ml against Staphylococcus aureus. The effect of ligand and complex structure on the antimicrobial activity was discussed.

The methanol, petroleum ether, chloroform, ethyl acetate, n-butanol and water extracts were obtained by extraction of marigold flower (Calendula officinalis L). The content of total phenolic compounds, determined by UV spectrophotometric method using the Folin-Ciocalteu reagent, was 15.12 mg/g. The content of total flavonoids, determined by UV spectrophotometric method according to Markham, was 5.13 mg/g. Qualitative determination of phenolic compounds in the extracts was performed by one- and two-dimensional thin-layer chromatography (TLC) procedures. The results of one- and two-dimensional TLC analyses showed that different flavonoids and phenolic acids were present in the investigated extracts. The greatest number of flavonoids (rutin, quercetin and some unidentified flavonoid glycosides) and phenolic acids (chlorogenic, caffeic, coumaric and vanillic acid) were deteminated in methanol extract. The influence of marigold extracts, in concentration range 0.6-1.2 mg/mL, on 2,2’-diphenyl-1-picrylhydrazyl (DPPH) free radicals was investigated by electron spin resonance (ESR) spectroscopy. All extracts showed scavenging activity (SA) in the following order: ethyl acetate > n-butanol > methanol > water > chloroform > petroleum ether. The SA increased with increasing concentration of extracts. The ethyl acetate and n-butanol extracts exibited the most significant SA. These extracts in concentration of 1.2 mg/mL eliminated completely DPPH radicals. The lowest SA had chloroform and petroleum ether extracts (in concentration of 0.6 mg/mL SA=0%). The SA of marigold extracts is attributed to its hydrogen-donating ability and scavenging effect.

An efficient stereospecific synthesis of 3’-deoxythymidine has been achieved, starting from D-xylose. The key step of the synthesis involved the NBS promoted conversion of 5-O-benzoyl-2,3-di-S-ethyl-2,3-dithio-D-ribose diethyl dithioacetal (4) into the 1-O-acetyl-5-O-benzoyl-2,3-di-S-ethyl-2,3-dithio-ß-D-ribofuranose (5) followed by the stereospecific coupling of the intermediate 5 with silylated thymine, in the presence of ethylaluminium dichloride as the catalyst.

This paper attempts to lead the reader an understanding of what free radicals are and how they can form during lipid oxidation. Also, it provides some information out natural antioxidants (tocopherols and tocotrienols flavonoids, polyphenols, tannines, melanoidihes, carotenoids, ascorbates) and the echanisms of their protection from radical damage. The sources of natural antioxidants are: oil seeds, teas, vegetables, fruits, spices and herbs.

Chlorides of copper(II) and nickel(ll) react with 1-benzoyl-2-methylbenzimidazole or 1-(4-chlorobenzoyl)-2-methylbenzimidazole to give complexes of the type [M(L)nCln(H20)∙Cln (M = Cu or Ni; L = (1-benzoyl-2-methylbenzimidazole or 1-(4-chlorobenzoyl)-2-methylbenzimidazole; n=O, 1 or 2). The complexes were synthesized and characterized by elemental analysis, molar conductivity magnetic susceptibility measurements and IR spectra. These studies suggest that all the complexes possess an octahedral stereochemistry. The antibacterial activity of (1-benzoyl-2-methylbenzimidazole or 1-(4-chlorobenzoyl)-2-methylbenzimidazole and their complexes was evaluated against Escherichia coli and Bacillus sp.

Sensitivity of natural antioxidants could be improved using encapsulation technologies. In this study, encapsulation of beetroot juice (BJ) with soy proteins has been optimized in terms of the wall:core ratio, BJ dilution and mixing time of both components, maximizing DPPH radical scavenging activity (SA) and the encapsulation efficiency (EE) based on the total phenolics content. Multi response optimization has indicated that the optimal encapsulation is accomplished when soy protein is mixed with undiluted BJ at a wall:core ratio of 50 g/L for 9.8 min. Applying these conditions, the optimal encapsulate has been produced, where the contents of total phenolics, flavonoids and betalains were 150.71 mg GAE/100 g, 9.31 mg RE/100 g, and 521.28 mg/100 g, respectively, while EE and SA were in accordance with the values obtained by optimization, i.e. 92.48% and 1.01 mmol TE/100 g, respectively, confirming the validity of the optimization process. The resulting encapsulates have favorable physicochemical and functional characteristics and can be potentially applied as natural color additives. [ABSTRACT FROM AUTHOR]

Objective: Goji fruit extracts, methanol (MGE) and hexane (HGE), were subjected to evaluation as potential source of phenolic antioxidants and antiradical activity.Methods: Some phenolic compounds (gallic, protocatechuic, vanillic, chlorogenic, coumaric, caffeic and ferulic acid and catechin and rutin), vitamin C and carotenoids were identified and quantified by HPLC. Antioxidant activity was tested by measuring ability to scavenge DPPH and hydroxyl radicals. Also, reducing power of goji fruit extracts was determined.Results: HPLC analysis results showed predominance of gallic acid (40.44 mg/g g.f). Vitamin C content in MGE was 716.91 mg vitC/100 g g.f. IC50DPPH· varied from 26.64 μmolTEAC/g for HGE to 62.15 μmolTEAC/g for MGE, while RP0.5 values varied from 952.23 μmolTEAC/g for MGE to 1360.48 mg/mL for HGE. IC50·OH for MGE was 1844.01 μmolTEAC/g.Conclusions: Our results support the use of goji fruits as rich sources of phytochemicals for further utilization in the food industry as supplements and functional food ingredients. [ABSTRACT FROM AUTHOR]