Publications by authors named "Ivica Ljubenkov"

Exposure to environmental pollutants and human microbiome composition are important predisposition factors for tumour development. Similar to drug molecules, pollutants are typically metabolized in the body, which can change their carcinogenic potential and affect tissue distribution through altered toxicokinetics. Although recent studies demonstrated that human-associated microorganisms can chemically convert a wide range of xenobiotics and influence the profile and tissue exposure of resulting metabolites, the effect of microbial biotransformation on chemical-induced tumour development remains unclear.

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Extreme environmental conditions affect the synthesis and accumulation of bioactive metabolites in halophytic plants. The aim of this study was to investigate the presence and quantity of key health-promoting phytochemicals in Croatian sea fennel, one of the most popular Mediterranean halophytes with a wide range of uses. The EOs were characterised by a high content of limonene (up to 93%), while the fatty acid profile shows a low content of oleic acid and the presence of valuable linoleic acid (ω-6) and linolenic acid (ω-3) in high percentages.

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The lipoxygenase pathway has a significant influence on the composition of the volatile components of virgin olive oil (VOO). In this work, the influence of the maturity index (MI) on the activity of the lipoxygenase enzyme (LOX) in the fruits of the autochthonous Dalmatian olive cultivars Oblica, Levantinka and Lastovka was studied. The analysis of the primary oxidation products of linoleic acid in the studied cultivars showed that LOX synthesises a mixture of 9- and 13-hydroperoxides of octadecenoic acid in a ratio of about 1:2, which makes it a non-traditional plant LOX.

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A single phenolic group and even a compound play different roles in the sensory properties and stability of virgin olive oil (VOO), which in turn are strongly influenced by several factors. Understanding the causes of differences in phenolic compound composition and oxidative stability (OS) in VOOs is essential for targeted and timely harvest and processing while maintaining desired oil quality. The phenolic profile and OS of two monocultivar VOOs (Oblica and Leccino) grown in two geographical sites of different altitudes (coastal plain and hilly hinterland) were analyzed throughout the ripening period over two years.

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The composition of free volatile compounds of essential oils (EO) and hydrosols (Hy) from four different localities of the species ssp. (Baumg.) Eb.

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Previous research on specialized metabolites of olive leaves has focused on the phenolic components and their biological role. The research in this article focuses on the metabolites that form free volatile compounds (FVCs). The composition of FVCs is divided into compounds isolated in the oil phase (essential oils; EO) and in the aqueous phase (hydrosols; Hy) from leaves of L.

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With the increasing interest in obtaining biologically active compounds from natural sources, (L.) Greuter (Asteraceae) came into our focus as a readily available and aromatic wild shrub widely distributed in the Mediterranean region. This work provides a phytochemical profile of in terms of parallel chemical composition in the lipophilic fraction (essential oil) and the water fraction (hydrosol).

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In this study, the influences of temperature (20, 40 and 60 °C) and extraction solvents (water, ethanol) on the ultrasound-assisted extraction of phenolics from the Adriatic macroalgae and were studied. The extracts were analysed for major phenolic sub-groups (total phenolics, flavonoids and tannins) using spectrometric methods, while the individual phenolics were detected by HPLC. The antioxidant activities were evaluated using three methods: Ferric Reducing/Antioxidant Power (FRAP), scavenging of the stabile 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and Oxygen Radical Antioxidant Capacity (ORAC).

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Onions are one of the most widely grown vegetable crops. As production increases, so does the generation of waste from various parts of the onion, raising the need for efficient ecological disposal and use of such waste products. However, onion waste products are a rich source of antioxidants with a range of biological properties, therefore, they could potentially be used in food and pharmaceutical industries.

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Sensory quality is of increasing importance to consumer decisions in choosing a product, and it is certainly an important factor in repurchasing in terms of meeting the necessary aroma quality and taste properties. To better understand the effects of rootstocks and scions on fruit quality, the sensory profile and volatile aroma composition of the fruits of hydroponically grown tomato plants were evaluated. Experiments were established using the tomato cultivars Clarabella and Estatio as scions during two spring-summer seasons.

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The phenolic extracts of fifteen Mediterranean medicinal plants, as well as their antioxidant and antimicrobial activities were investigated to grade their potential as additives in the food industry. Phenolic profiles of plant extracts were determined spectrophotometrically (total phenolics and phenolic subgroups) while individual compounds were identified using chromatographic assays. The biological activity of samples was determined using five antioxidant assays, while the antibacterial potential was determined against six foodborne pathogens ( Infantis and ).

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In this study, the effect of a four-stage chemical refining process (degumming, neutralization, bleaching, deodorization) on the quality parameters, fatty acid composition and volatile compounds of crude oils produced from processing by-products of farmed fish species (tuna, seabass and gilthead seabream) was evaluated. The quality of the oils was compared to commercially available cod liver oil on the basis of free fatty acid, peroxide value, -anisidine, total oxidation (TOTOX), thiobarbituric acid reactive species (TBARS), oxidative stability at 80, 100 and 120 °C, tocopherol content, and volatile components, while the fatty acid profile and the proportion of polyunsaturated fatty acids (PUFAs) were used as an indicator of the nutritional values of fish oils. Quality parameters of the studied oils and oil oxidative stability were enhanced with refining and were within the limits recommended for fish oils without the loss of PUFAs.

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or is a Croatian autochthonous grape variety which is a parent of the America's most popular variety or Italian . The aim of this study was to investigate the dynamics of extraction of phenolics and changes in antioxidant activity of the samples collected during maceration of grapes processed using two different macerating enzymes. According to the obtained results it can be concluded that wines from grapes are great source of bioactive phenolics although differences in phenolic profiles between control and enzyme-treated wines were detected.

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The quality parameters, a variety of microcomponents, and the sensory characteristics of Oblica and Leccino cv. virgin olive oils (VOOs) were evaluated before and after filtration process adopted in order to estimate the individual varietal compositional changes. The dynamics of the formation of hydrolytic and oxidative changes in unfiltered (UF) and filtered (F) oils was asses by comparing level of free fatty acids (FFA), peroxide value (PV), and spectrophotometric indices periodically during 1 year of oil storage.

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belongs to the Brassicaceae family, which represents a forgotten crop of the Euro-Mediterranean area. The aim of the present study was to determine the glucosinolate profile in different plant parts and biological properties (antioxidant, anticholinesterase, and cytotoxic activities) of the isolates containing glucosinolate breakdown products. The chemical profiles were determined by using HPLC-PDA-MS/MS of desulfoglucosinolates and GC-MS of glucosinolate degradation products.

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Samples of white and red wines produced in two different wine-growing regions, coastal (Dalmatia) and continental (Hrvatsko zagorje) of Croatia, were analysed for biogenic amines content. Biogenic amines content was determined, and its concentration levels were associated with the geographical origin of the wine. Due to its high sensitivity, HPLC method with ultraviolet detector was used, including the derivatisation step with dansyl chloride.

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is one of the most devastating pests in tomato greenhouse production. Insecticide resistance management for requires a novel approach that maximizes non-chemical methods for pest control. The aim of this study was to test the effects of rootstocks on populations in hydroponically grown tomato plants.

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Here, we report a comparative study of the phytochemical profile and the biological activity of two onion extracts, namely L. and × (Clementi ex Visiani 1842), members of the family Amaryllidaceae. The identification of flavonoids and anthocyanins, and their individual quantities, was determined by high-performance liquid chromatography (HPLC).

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Sea fennel, a rediscovered star of the coastal cuisine, has been investigated for its phytochemical profile and biological potential. Sea fennel flowers, stems and leaves were analyzed for essential oils (EOs) isolated by hydrodistillation, as well as non-volatiles obtained by ethanolic extraction. Limonene were found to be a dominant compound in EOs and ethanolic extracts; ranging from 57.

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Over the last years, great interest has arisen concerning plant stilbenes, especially resveratrol, which has a whole spectrum of positive biological activities. In this study, we investigated the presence of resveratrol monomers (trans- and cis- form) and naturally occurring derivatives of trans-resveratrol (piceid, astringin and isorhapontin) in phenolic extracts of twenty medicinal plants traditionally used in Croatian folk medicine. The investigated compounds were present in the samples, in free form or as glucosides, and the highest share was found in immortelle, common yarrow and Lamiaceae plants.

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In plant tissues, enzymes implicated in the lipoxygenase (LOX) pathway are responsible for the hydroperoxydation of polyunsaturated fatty acids, ultimately leading to the production of small chemical species involved in several physiological processes. During industrial olive oil production, these enzymes are activated upon crushing and grinding of olive fruit tissue, subsequently leading to the synthesis of volatile compounds responsible for the positive aroma and flavor of the oil. An investigation of LOX activity during olive fruit ripening and malaxation could assist in the production of oils with favorable aroma and taste.

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Chamomile, common yarrow and immortelle ethanolic extracts were chemically analysed with respect to phenolics. Twelve phenolic acids were separated and identified by HPLC-DAD and the presence of rosmarinic acid was additionally confirmed by LC-MS. Five methods were applied for the evaluation of extracts' antioxidant properties (FRAP, DPPH, ABTS, chelating activity, Briggs-Rauscher reaction), while the antibacterial activity was tested against some of the major food-borne pathogens (Campylobacter coli, Escherichia coli, Salmonella Infantis, Bacillus cereus, Listeria monocytogenes and Staphylococcus aureus).

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The aim was to investigate the phenolic content, antioxidant capacity, and antibacterial activity of Dalmatian sage (Salvia officinalis L.) leaves collected during different vegetation periods. Separation and quantification of the individual phenols were performed by reversed-phase (RP)-HPLC coupled with a PDA (photodiode array) detector and using an internal standard, while the contents of total phenols, flavonoids, flavones, and flavonols were determined spectrophotometrically.

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In contrast to the well-described various biological effects of grape wines, the potential effects of commonly consumed blackberry wine have not been studied. We examined in vitro antioxidant and vasodilatory effects of four blackberry wines and compared them with the effects of two red and two white grape wines. Although some blackberry wines had lower total phenolic content relative to the red grape wines, their antioxidant capacity was stronger, which may be related to a higher content of non-flavonoid compounds (most notably gallic acid) in blackberry wines.

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This study aimed to research the influence of phenophase on the phenolic profile (phenolic acids, flavonoids and stilbenes) and related antioxidant properties of sage, one of the most characteristic plants of Dalmatian karst. The total phenol and flavonoid contents in sage leaves were determined spectrophotometrically, while the principal phenolics were determined using HPLC-RP-DAD. Antioxidant properties of this well known medicinal plant were determined as free radical scavenging activity (DPPH), ferric reducing/antioxidant power (FRAP) and by Briggs-Rauscher oscillating reaction (BR).

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