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The nutritional quality and sensory properties of virgin olive oils (VOO) are strongly influenced by a complex endogenous enzyme system. The activity of these enzymes can be influenced by the process conditions during oil production. The aim of the present study was to determine the influence of flash thermal treatment (FTT) on lipoxygenase activity and on the formation of volatile compounds. Olive fruits from Istarska bjelica and Levantinka were used for this experiment. FTT was performed as a pretreatment to malaxation by rapid cooling or heating from 15 to 40 °C. Lipoxygenase was isolated from the olive paste after malaxation, and its activity was determined by measuring the concentration of hydroperoxides formed by the HPLC method. The volatile compounds of VOOs were analyzed by SPME - GC/MS. The results show that lipoxygenase activity is cultivar dependent, with Levantinka having significantly higher activity. Consequently, Levantinka VOOs have significantly higher concentrations of lipoxygenase pathway volatile compounds. FTT had no significant effect on lipoxygenase activity, although the trend of decreasing activity with increasing temperature was observed. However, volatile compounds of the produced oils were temperature dependent, and their concentration increases from 15 °C to 20 °C for Levantinka and to 25 °C for Istarska bjelica. Thereafter, it gradually decreases with increasing temperature. The concentration of secondary oxidation products was also determined to determine the influence of the temperature on the oxidation processes. Neither the cultivar nor the FTT had any effect on the oxidation products.

Production of natural compounds from medicinal plants with numerous biological effects has become very popular due to increasing concerns about the safety of using synthetic substances and the effects of COVID -19 on health. Sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson), (SB) is known as an important source of natural antioxidant and antimicrobial bioactive molecules (BAM), but also, when added to foods, improves sensory properties, microbiological stability, and shelf life of products. The best-known sea buckthorn product is berry oil (SBO) (Yu et al., 2017), which contains large amounts of lipophilic BAM such as unsaturated fatty acids, tocopherols, carotenoids, and sterols (Koskovac e al., 2017), but differences in composition have been found depending on the cultivar, growing conditions and extraction methods used (Christe et al., 2020 ; Cenkowski, 2006). Supercritical CO2 extraction of oil as an advanced method is gaining popularity due to its better extraction efficiency compared to conventional extraction methods. Moreover, CO2 as an environmentally friendly and safe solvent (GRAS) can be easily removed from oil. Therefore, the aim of this study was to determine the content of fatty acids, sterols, and α-tocopherols, as well as the antioxidant capacity (AC) of SBO obtained by supercritical CO2 extraction from SB berries from Croatia. The tocopherol content of the SBO extracts was determined by HPLC/FLD, the content of fatty acids and sterols by GC-MS and AC by the lipophilic ORAC method. A total of 16 sterols were determined, with sitosterol (589.28 mg/100 g oil) being the most abundant, followed by campesterol (31.97 mg/100 g oil), uvaol (21.79 mg/100 g oil), and obtusifoliol (12.99 mg/100 g oil). High content of unsaturated fatty acids such as omega-7 palmitoleic acid (34.54%) and omega-6- γ-linolenic acid (10.78%) was also found. SBO was characterized by high content of α-tocopherol (275.63 mg/100 g oil) and high antioxidant ORAC capacity (1676.90 μmol TE /100 g oil). The results suggest that the SBO obtained by supercritical CO2 extraction is a rich source of various lipophilic BAM with high antioxidant capacity, which could be used for the production of natural products, functional foods and as food additives.

Fennel (Foeniculum vulgare Mill.) is a perennial aromatic and medicinal plant belonging to the Apiaceae family. It originates from the Mediterranean area, but it has spread worldwide through naturalization and cultivation. The use of fennel in culinary purposes and traditional medicine is known from ancient times, but nowadays its application has been extended to the pharmaceutical, cosmetic and food industries. Although different parts of fennel (leaves, young shoots, roots and seeds) can be utilized, fennel seeds are mostly exploited due to their abundance of essential oil (up to 5-6%) which is characterized by a strong and pleasant aroma. Fennel essential oil has been recognized to possess antimicrobial, antifungal and antioxidant properties, therefore it is widely used in various areas. The chemical composition of fennel essential oil showed up to 80 volatile compounds, among which trans-anethole, fenchone and estragole are major compounds, being the key compounds of the characteristic fennel flavor. Besides these compounds, the presence of other compounds such as α- and β-pinene, myrcene, α-phellandrene, limonene and p-anisaldehyde have also been reported. The isolation of essential oil can be accomplished by various extraction techniques, such as hydrodistillation (HD) and steam distillation (SD) which are known as conventional ones and still are the most common in use. They are effective for the extraction of essential oils from spices and herbs from which such oils are difficult to isolate and they do not include the use of chemical solvents. On the other hand, their main drawbacks are long duration, difficult regulation of heat and possible loss of thermolabile and light volatiles. Therefore, in order to overcome these deficiencies, advanced extraction techniques have been developed, including microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), ultrasound-assisted extraction (UAE), subcritical water extraction (SWE) and supercritical fluids extraction (SFE), namely extraction with supercritical carbon dioxide (SC-CO2) which is considered “green” showing the most promising beneficial effects due to being sustainable, environmentally friendly and cost-effective. However, regardless of the selected extraction technique, it is necessary to define optimal process conditions taking into account all process parameters in accordance with the raw material used, and optimize the extraction process with the intention to achieve the maximum yield of essential oil of the best quality and unaltered composition.

Innovative technologies are being widely studied for their application in the production of virgin olive oil. Flash thermal treatment is one of these techniques, since the regulation of temperature allows control over complex enzyme systems that affect the nutritional value, oxidative stability and sensory profile of virgin olive oil [1-3]. The aim of this study was to determine the effects of flash thermal treatment (both cooling and heating) on the antioxidant activity of virgin olive oil from four different varieties (Oblica, Rosulja, Istarska bijelica and Levantinka). Flash thermal treatment was applied at 6 different temperatures in the range of 15-40 °C. It was used as a malaxation pretreatment for the production of virgin olive oil on a laboratory scale using the Abencor system. The antioxidant activity of the produced oils was determined using the DPPH method previously described by Kraljić et al [4]. The results show a significant influence of the variety and pretreatment on the antioxidant activity of virgin olive oil, as well as their interaction. Rosulja had the highest antioxidant activity (90.8% on average) compared to the other three varieties (84.3, 75.6 and 74.8% for Oblica, Istarska bijelica and Levantinka, respectively). In relation to the applied flash thermal treatment, Oblica, Rosulja and Levantinka showed significantly higher antioxidant activity at the highest temperature (40 °C), while Istarska bijelica responded better to mild temperatures (20-30 °C).

Medicinal plant extracts can serve as the functional constituents for the dairy products enrichment due to the presence of bioactive compounds. Except beneficial effect on human health, plant extracts also have antimicrobial activity which can extend shelf life of foods. Plant extracts can be dried and added to milk raw materials in the powder form and the choice of extraction technique and conditions significantly affect the yield of target groups of bioactive molecules in powder production. In this study the yields of total phenolics (TP), flavonoids (TF), hydroxycinnamate acids (THCA), flavonols (TFL) and pigments (TPIG) of carob pod (Ceratonia siliqua L.), bay (Laurus nobilis L.) and sage (Salvia officinalis L.) leaves were evaluated using different extraction techniques and solvents, respectively. The selected plants were successive extracted with hexane, 80%-acetone and 96%-ethanol in shaking water bath (SWB) and under ultrasound-assisted (UAE) and accelerated solvent extraction (ASE). Mass fraction of TP, TF, THCA, TFL, TPIG were determined by spectrophotometric methods. The highest TP, TF and THCA content was determined in sage extracts obtained by UAE and the highest TFL content by SWB technique. Laurel extracts had the highest TPIG content using a SWB and ASE technique. In general, sage was richer source of phenolics and laurel of pigments while UAE technique was better method for phenolic and ASE for pigments extraction.

Medicinal and aromatic plants are a rich source of structurally diverse bioactive molecules (BAM) (polyphenols, dietary fiber, sterols, pigments, polysaccharides, vitamins, minerals, etc.) which possess various biological activities, and have a great potential for the application in food, pharmaceutical and cosmetic industry. Extraction is one of the most important steps in BAM isolation and can be affected by the applied extraction techniques, conventional or advanced with lower organic solvent consumption (microwave assisted, ultrasound assisted, pressurized liquid extraction, etc.) as well as various extraction conditions (pH, time, temperature, pressure, particle size, solvent, sample/solvent ratio, microwave power, etc.). Furthermore, for the dairy industry and production of enriched functional dairy products, liquid plant extracts are often processed into a more stable powder form by using appropriate encapsulation techniques. Therefore, this paper presents a systematic and comprehensive review of techniques used in the production of liquid plant extracts and powders, which have a great perspective for the application in the production of functional and/or enriched dairy products. Besides selection of the efficient extraction techniques and optimal extraction conditions, it is also important to conduct the economic feasibility study to determine which technique is the best choice for sustainable plant extracts and powder production from technical and economic aspects.

The oxidative stability of fats and oils is a crucial parameter that determines the shelf life of a product, but also the general use of the fats and oils. Differential scanning calorimetry (DSC) is a promising new technique that is fast, reliable and uses the exothermic character of the oxidation reaction to determine the induction time (in the isothermal DSC method) or the induction temperature (in the non-isothermal, i.e., dynamic DSC method). The objective of the present study was to optimize the conditions of the DSC method to determine the oxidative stability of virgin olive oil. Both the isothermal and dynamic methods were developed on a 214 Polyma DSC (NETZSCH-Gerätebau GmbH) and optimized using extra virgin olive oil from the Croatian market. The parameters studied were sample size (4, 8 and 12 mg), sample preparation (use of an open or a sealed pan with a pinhole), temperature (130, 140 and 150 °C) for the isothermal method and heating rate (5, 10, 15 and 20 °C/min) for the dynamic method. The results show that the DSC method is a reliable method for determining oxidation stability for both isothermal and non-isothermal methods. Sample size did not affect induction time, but a smaller portion size resulted in better reproducibility of the results. Regarding sample preparation, there was no statistical difference between results obtained with an open or sealed aluminum pan. However, it is better to use a hermetically sealed pan with a pinhole to protect the instrument from possible contamination. The induction time at 130 °C was 287 minutes, which was considered unacceptable, while a temperature of 140 °C proved to be optimal. A temperature of 150 °C also showed satisfactory reproducibility of results, but a longer induction time at 140 °C makes it easier to track changes between different oils or during storage. For the determination of the induction temperature (dynamic DSC), a heating rate of 15 °C/min proved to be optimal. Although repeatable results were also obtained with a heating rate of 10 °C/min, the use of a higher temperature rate can significantly speed up the analysis. The other two heating rates were considered unsuitable due to the lack of reproducibility.

Recently, various techniques have been developed for encapsulating bioactive compounds to convert them into a more stable form. One of them is electrostatic extrusion, which is highly recommended for hydrophobic bioactive compounds such as essential oils (EOs). Among the various polymers, alginate is most commonly used as a core material. This is a naturally occurring polysaccharide found in brown algae and is characterized by high viscosity, gelling properties, high stability, low cost and non-toxicity. Sage (Salvia officinalis L.) is a perennial aromatic and medicinal plant of the Lamiaceae family. In addition to various phytochemicals, it also contains EOs which are found to have antioxidant, antimicrobial, antifungal, insecticidal and antiproliferative properties. Therefore, this study investigated the development of alginate-based beads containing sage EO prepared by electrostatic extrusion. For the preparation of beads, the content of alginate (0.5, 1 and 1.5%, w/v) and calcium chloride (CaCl2) (3 and 5%, w/v) was varied. Alginic acid sodium salt (low viscosity), previously dissolved in distilled water, sage EO (5%, w/v) and Tween 20 (0.5%, w/v) were homogenized at 10 000 rpm for 4 min. Beads were prepared with Büchi encapsulator B-390 (Flawil Switzerland) using a 1 mm stainless steel needle at a frequency of 80 Hz, a pressure of 1000 mbar, an amplitude of 6 and an electrostatic potential of 500 V. After collection in CaCl2 solution, the beads were washed in distilled water, drained and used for further analysis. Encapsulation yield (%) was expressed as the ratio between the amount of beads obtained and the amount of emulsion used for the encapsulation. The size of the beads was measured using a micrometer screw gauge and the average dmax, dmin and sphericity factor (SF) were calculated. All analyzed parameters were significantly affected by alginate and CaCl2 content, except for SF (Table 1). The highest encapsulation yield and bead size were obtained at the highest concentrations of alginate and CaCl2. In addition, the beads generally maintained their roundness. Although not significant, most spherical beads were produced with 1.5% alginate, while a lower CaCl2 content resulted in slightly elongated shape of the beads.

Aim: Pulsed electric field (PEF) is an emerging new technology that is finding more and more applications in the food sector. Virgin olive oil is no exception, as its application can significantly increase oil yield. However, changes in the chemical composition of virgin olive oil vary from study to study. This could be due to the fact that the chemical composition of the oil is directly influenced by the endogenous enzymes of the olive fruit responsible for the distribution of polyphenols in virgin olive oil and its sensory properties. Therefore, the aim of this study was to determine the effect of PEF on endogenous olive enzymes in model systems. Methods: Model systems of commercial enzymes (β-glucosidase and lipoxygenase) and their substrates (p- nitropheniygluco-pyranoside and linoleic fatty acid, respectively) were treated with HVG60/1 PEF (Impel, Zagreb, Croatia) for 1, 2, and 5 min with voltages of 0.1 and 0.5 kV/cm2 and a frequency of 25 and 125 Hz. Then, the treated enzyme/substrate solution was incubated at 25°C for 30 minutes to simulate a malaxation process. The activities of the enzymes were determined spectrophotometrically. Results: The activity of PEF-treated enzymes increased 4.5- fold for β-glucosidase and 2-fold for lipoxygenase compared to the untreated enzymes. The β- glucosidase activity measured immediately after PEF treatment was significantly affected by all factors and also by the interaction of voltage and time and frequency and time. Higher voltage resulted in an increase in β-glucosidase activity with longer treatment duration. After an additional 30-min incubation at 25 °C, β- glucosidase activity was affected only by PEF voltage, whereas it increased with higher voltage. Immediately after PEF treatment, lipoxygenase activity for linoleic fatty acid was significantly affected by treatment duration, with longer PEF treatments increasing activity. However, after incubation, longer treatment time resulted in lower amounts of hydroperoxides produced, which might be related to their spontaneous degradation. Conclusion: The introduction of PEF in virgin olive production as a pretreatment of malaxation could lead to a higher concentration of phenols and an improvement of the sensory characteristics of the oil due to an increased enzymatic activity.

Since bioactive molecules are extremely sensitive to a number of external factors and are often unstable, they must be protected and stabilized by encapsulation methods such as spray drying and electrostatic extrusion. Myrtle (Myrtus communis L.) has long been known for its beneficial therapeutic effects on disorders of various organic systems. Its essential oil is obtained by distillation of the leaves and contains various terpenoids, with 1, 8-cineole, myrtenyl acetate, and α-pinene predominating. Alginates isolated from brown seaweed are often used as carriers for encapsulation due to their gel forming property in the presence of divalent cations such as calcium where alginate solution containing bioactive compounds is first dispersed into small droplets and then solidified by gelation. Therefore, the aim of this study was to investigate the possibility of stabilization of myrtle essential oil by the formation of brown algae alginate beads. Myrtle essential oil beads were prepared by electrostatic extrusion encapsulation and the effect of the concentrations of sodium alginate as carrier (0.5, 1 and 1.5%) and calcium chloride as recipient (3 i 5%) on the yield and physical properties of the beads was studied. Myrtle essential oil (5%) was added to sodium alginate solutions together with 0.5% Tween 20 as emulsifier and homogenized with a mechanical stirrer at 10, 000 rpm for 4 min. Droplets were formed by extrusion on Büchi encapsulator by applying electrostatic potential of 500 V, frequency 80 Hz with 1 mm needle tip. Yield (Figure 1) was calculated as percentage of wet beads weight and showed significant differences between formulations. The lowest yields were obtained for the samples with the lowest concentration of Na-alginate (0.5%). For both CaCl2 concentrations an increase in encapsulation yield was observed with increasing Na-alginate concentration with the highest value determined in the sample prepared with 3% CaCl2 solution. Largest beads (Table 1) were produced with 1.5% alginate and 5% CaCl3 while 3% CaCl3 caused less variation between samples. Sphericity improved greatly with the addition of higher levels of Na-alginate.

Myrtle (Myrtus communis L.) is an evergreen aromatic shrub characteristic for Mediterranean area which has long been known for its many positive therapeutic effects. Myrtle leaf essential oil is used in the food and beverage, perfume and cosmetics industries as well as aromatherapy while berries are most commonly used as food spice and in liqueurs production. Myrtle essential oil is produced by water or steam distillation of its leaves, however, due to the low volatiles content, the yield is quite low. Therefore, to minimize the loss of volatile compounds of interest and reduce the particle size to a fine powder, cryogenic grinding at -196 °C can be used as an innovative grinding technique and a pre- treatment for the distillation. The influence of cryogenic grinding of myrtle leaves on the essential oil yield, quality and quantity of its components obtained by distillation on a Clevenger apparatus was investigated with the aim of shortening the distillation time and obtaining an essential oil with better properties. Cryogenic grinding of myrtle leaves was performed at 3, 6 and 9 minutes with untreated leaves used as control and the distillation time was set at 30, 60 and 90 minutes. GC-MS analysis of myrtle essential oil was able to detect and quantify 22 volatile constituents, mainly terpenoids, where the dominant compounds were 1, 8-cineol, myrtenyl acetate, α-pinene and linalool. Cryogenic grinding applied for 3 minutes, compared to the control, was able to significantly increase the yield and concentrations of individual compounds. This effect was specifically notable for low- boiling-point volatile compounds such as α- pinene, myrcene and 3-carene which concentrations increased 26.0, 28.2 and 28.9%, respectively, while total volatiles content increased by 9.8%. On the other hand, longer grinding time caused decrease of high-boiling- point volatile compounds and lower total volatiles content compared to the control. Considering the interaction of grinding and distillation time, total volatiles were the highest with 3 minutes of cryogenic grinding and 30 minutes of distillation yielding 18.1% more than with control in the same time period.

Mirta (Myrtus communis L.) je višegodišnji samonikli grm koji raste na području Mediterana te je od davnina poznat po svojim blagotvornim terapeutskim učincima na organizam, posebice u liječenju probavnih (dijareja), dišnih (astma) i dermatoloških tegoba (psorijaza). Isto tako, bobice mirte koriste se u proizvodnji likera, a samljeveni listovi i u kulinarske svrhe tj. kao začin. Najznačajniji spojevi koji se nalaze u listovima mirte su fenolni spojevi, flavonoidi, tanini i monoterpenoidi dok su bobice dobar izvor antocijana i masnih kiselina. Ekstrakcija takvih spojeva se u novije vrijeme provodi alternativnim tehnikama koje reduciraju upotrebu otapala ili ih uopće ne koriste, ekološki su prihvatljive te su ekonomski dugoročno isplative. Jedna od njih je ekstrakcija superkritičnim CO2 pomoću koje je provedena izolacija bioaktivnih molekula iz bobica mirte. U ovom istraživanju, prema Box-Behnken dizajnu eksperimenta sa 17 pokusa i 5 ponavljanja u centralnoj točki, provedena je optimizacija procesa ekstrakcije. GC-MS analizom identificirano je 18 hlapljivih spojeva od kojih su dominantni bili mirtenil-acetat, 1, 8-cineol i α- pinen. Analiza varijance pokazala je značajan utjecaj temperature, tlaka i protoka CO2 na iskorištenje ekstrakcije i udjele pojedinih sastavnica. Definirani su uvjeti u kojima se postiže maksimalno iskorištenje ekstrakcije i najviši udjeli dominantnih hlapljivih spojeva – temperatura od 60 °C, tlak od 200 bara i protok CO2 od 40 g/min.

Due to their great diversity, Mediterranean plants possess a wide range of bioactive molecules among which the pigments represent one of the major constituents. Thus, this study examined composition and properties of pigments from several Mediterranean shrubs and subshrubs (Myrtus communis, Pistacia lentiscus, Thymus vulgaris, Salvia officinalis, and Laurus nobilis) collected in the Adriatic coastal area. Pigments were extracted by successive solvent extraction of leaves with hexane, 80%-acetone, and 96%-ethanol and agitation-assisted extraction (AAE), ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) were compared. In the obtained extracts, the content of total pigments and antioxidant capacity were determined spectrophotometrically, while individual chlorophylls and carotenoids were analyzed using HPLC DAD analysis. Pheophytin a, b and b’, followed by chlorophyll a and b, were dominant chlorophyll molecules while lutein and β-carotene were dominant carotenoids. Overall extracted pigments were determined in the range of 73.84 – 127.60 mg 100 g-1 and were the lowest in T. vulgaris with no significant differences between other species, while M. communis extracts contained the most carotenoids. Antioxidant capacity was highest in M. communis and P. lentiscus and showed a moderate positive correlation with carotenoids and chlorophylls levels. Even though AAE and PLE had similar efficacy, preference can be given to the PLE method due to its shorter extraction time and lower solvent consumption. Successive solvent extraction has confirmed differences in the polarity of determined pigments as most of them had medium-level polarity and dissolved in 80%-acetone as a medium polar solvent. Examined plant species certainly expressed their diversity and potential in the application of various functional products.

Recent advancement in extraction methods are opening wide possibilities in utilizing different plant materials as a basis for the production of cosmetic and pharmaceutical ingredients. This study aimed to compare the yield of total oil extracted using three methods with hexane as a solvent - Accelerated Solvent Extraction (ASE) at 25 and 100 °C, Soxhlet Extraction (SE) and Extraction by Agitation at room temperature (EA). Also, fatty acid profiles and differences between the spice seeds were investigated. Four different spice seeds were analyzed - fennel (Foeniculum vulgare), caraway (Carum carvi), coriander (Coriandrum sativum) and star anise (Illicum verum). Using Soxhlet method the highest yield of oil was found in coriander seed (18.8%), followed by caraway (13.4%), star anise (11.6%) and fennel (9.0%). Dominant fatty acid in seed oils from Apiaceae family (fennel, caraway and coriander) was petroselenic acid (C18:1n12), ranging from 80.2% in fennel by EA to 32.0% in caraway with ASE/100 °C. Type of seed and extraction method had a significant influence on its quantity (p≤0.01). Interesting results were noticed regarding fennel oil and to lesser extent caraway oil – during oxidation processes petroselenic acid degrades in lauric (C12:0) and caproic (C6:0) fatty acids with relatively stable sum of them between 82-85% of total fatty acids in fennel and 64-74% in caraway. The highest levels of C12:0 (32.8%) were determined using ASE/25°C and C6:0 (1.0%) with EA method. Other dominant fatty acids in fennel oil were linoleic (C18:2, avg. 8.4%) and palmitic (C16:0, avg. 3.1%). Dominant fatty acid in coriander oil (avg. 80.0%) and caraway oil (avg. 38.6%) was C18:1n12, followed by C18:2 (coriander avg. 13.5% ; caraway avg. 25.6%), C16:0 (coriander avg. 3.3% ; caraway avg. 2.2%), C12:0 (coriander avg. 0.3%, caraway avg. 17.3%) and C6:0 (coriander avg. 0.2%, caraway avg. 7.0%). Monounsaturated fatty acids dominated in all Apiaceae family samples with avg. 44.8% in caraway oil, 60.8% in fennel oil and 80.4% in coriander oil. In oils from star anise samples dominant fatty acid was lauric with avg. of 60.7%, followed by C18:2 (13.0%), C18:1n9 (12.2%) and C16:0 (8.2%). 89 Dominant group of fatty acids in star anise oil were saturated (71.7%). Statistically significant differences (p≤0.01) in oil yield were observed between the extraction methods: twofold higher results were achieved for star anise (11.9%) using ASE/100 °C and fennel (10.4%) with EA, while most of the other results were lower: 4.3-9.0% for ASE/25°C, 4.8-8.4% for ASE/100 °C and 6.8-12.2% for EA.

Spice seed oils are a subject of interest to the cosmetic and pharmaceutical industries, but the studies on this topic are limited. Characteristic color of spice seeds oils derives from naturally occurring pigments, which quantity varies due to the seed type as well as extraction conditions. Hence, this study aimed to examine differences in pigments content of seed oils upon a) seed type and b) oil extraction method. Oil from seeds of fennel (Foeniculum vulgare Mill.), caraway (Carum carvi L.), coriander (Coriandrum sativum L.) and star anise (Illicum verum Hook. f.) was produced using Accelerated Solvent Extraction (ASE) at 25 and 100 °C, standard Soxhlet extraction (SE) and extraction by agitation at room temperature (AE) using hexane as an extraction solvent. Accordingly, 16 oil samples were obtained and dissolved in acetone to examine the content (mg/100 g of oil) of chlorophyll a (Ch a), chlorophyll b (Ch b) and total carotenoids (TC) by spectrophotometry. Content of pigments was determined as follows: Ch a ranged from 0.58 – 30.98 mg/100 g, Ch b from 0.89 – 9.98 mg/100 g, while TC were determined in a range from 0.37 – 14.83 mg/100 g. Statistical analysis showed significant differences (p≤0.05) in pigments content among oil samples influenced by seed type as well as extraction method. Fennel oil had the highest concentrations of pigments (Ch a=23.60 mg/100 g, Ch b=8.83 mg/100 g, TC=12.31 mg/100 g). High concentrations of chlorophylls (Ch a=10.94 mg/100 g, Ch b=4.75 mg/100 g) were also present in star anise oil, however its content of TC was lower (1.20 mg/100 g). Interestingly, caraway oil had 4.82 mg/100 g of TC, while chlorophylls were less presented (Ch a=2.71 mg/100 g, Ch b=2.65 mg/100 g). The lowest contents of all analyzed pigments were determined in coriander oil (Ch a=1.73 mg/100 g, Ch b=2.16 mg/100 g, TC=0.66 mg/100 g). In relation to the extraction method, ASE/25 °C was the least exhaustive, while ASE/100 °C, SE and AE showed similar effectiveness. Finally, it can be concluded that fennel oil was the richest in pigments and ASE/100 °C could be highlighted due to the good efficiency in considerably shorter extraction time.

Marine organisms are potential sources of valuable bioactive molecules such as fatty acids, sterols and pigments which can be used in the development of new nutraceuticals and pharmaceuticals. Because of their high productivity, diversity and traditional diet consumption in China and Japan, particular interest is attributed to seaweeds. Considering that conventional extraction (CE) techniques are time consuming and require high solvent input, advanced techniques e.g. accelerated solvent extraction (ASE) are being developed. In this research, the impact of different solvents (hexane and ethyl acetate:ethanol 1:1 (v/v)) and extraction methods (CE and ASE at 25 and 100 °C) on the lipid extract yield, fatty acid and pigment composition of different types of seaweed were investigated. All the macroalgae (Cystoseira barbata, Codium bursa, Cystoseira compressa and Fucus virsoides) originated from the Adriatic Sea and were collected in the Zadar region. Palmitic (16, 98 %), oleic (26, 10 %) and linolenic (5, 97 %) fatty acids were the most represented in all four tested species. Macroalgae Cystoseira barbata had the best ω-6/ω-3 fatty acids ratio, while yield and total pigments were the highest in Fucus virsoides extracts. Solvent type had significant impact on total pigments, chlorophyll a, chlorophyll b, protochlorophyll with ethyl acetate:ethanol showing better efficiency. Even though ASE did not result in higher lipid extract yield, contents of carotenoids and total pigments were the highest in ASE 100 samples. Results of sterol determination which was made in order to obtain additional information for species differentiation showed that Cystoseira barbata extracts had the highest levels of total sterol among which fucosterol was dominant. Fucosterol also comprised more than 90 % of Fucus virsoides sterol profile while β-sitosterol was dominant in Codium bursa and Cystoseira compressa.

The sage (Salvia officinalis), laurel (Laurus nobilis), thyme (Thymus vulgaris), mastic tree (Pistacia lenticus L.), carob (Ceratonia siliqua) and myrtle (Myrtus communis) has many potential applications due to large number of bioactive molecules (BAM) with high antioxidant capacity (AOC). Currently it is an increasing interest in using these plants in the production of plant extracts (PE) and essential oils (EO) for food, pharmaceutical and cosmetic industries. However, extraction yield and antioxidant activity of PE depend on selection of appropriate extraction technique and solvent used for extraction. Therefore, the aim of this study was to determine the AOC of PE obtained by successive extraction with three different extraction solvents (hexane, 80 % acetone and 96 % ethanol) and extraction techniques (ultrasound assisted (UAE), accelerated solvent (ASE) and shaking water bath extraction). The plant extracts were analysed using the ORAC method. Results showed that ASE is the most appropriate method for extraction BAC’s from thyme, mastic tree and carob while UAE was better method for sage and laurel, whose extracts contribute the highest AOA.

Mastic tree (Pistacia lentiscus L.) and thyme (Thymus vulgaris L.) are traditional medicinal plants characterized with a wide spectrum of bioactive molecules, thus presenting a valuable source for various applications. For the extraction of natural antioxidants miscellaneous extraction methods are being used, among which accelerated solvent extraction (ASE) represents an advanced extraction technique. However, due to the diverse chemical structure, extraction of target compounds depends on the used solvent type. Hence, this study involved the three-step extraction of polyphenols and pigments from mastic and thyme dry leaves using ASE (60 °C/3×5 min) and agitation-assisted extraction (AAE) (60 °C/30 min) with solvents arranged by their polarity: hexane was used for the first fraction, followed by acetone (80%) and finally ethanol (96%). Obtained fractions were analyzed for total content of polyphenols (TP), hydroxycinnamic acids (THCA), flavonols (TFL), chlorophylls (TCHL) and carotenoids (TCAR). Statistical analysis of obtained results showed significant (p≤0.05) differences in fractions' composition among plants and applied extraction methods. Acetone fraction was the most abundant with all analyzed compounds accompanied with the greater ASE efficiency, especially in polyphenols’ isolation. In hexane and ethanol fractions, longer AAE time resulted with greater performance in extraction of polyphenols, while higher pigments yields were achieved with ASE. Although mastic tree dominated in TP content, extracts of both plants showed their abundance of bioactives, proving their potential for further implementation in various food products. Further optimization of ASE conditions could contribute to even better extraction efficiency.

Koje su sve zdravstvene blagodati Varaždinskog bučinog ulja? Da li jest i u kojoj mjeri bučino ulje prirodni antioksidans? Koje izazove treba savladati/prevladati ako želimo postići vrhunsku kvalitetu Varaždinskog bučinoga ulja? Mislite da povijest proizvodnje Varaždinskog bučinog ulja nije zanimljiva? Ili ste se možda zapitali koje namirnice mogu na bazi buče i bučinog ulja brzo i lako zamijeniti industrijske prehrambene proizvode?! Monografija Varaždinsko bučino ulje ne samo da objedinjuje sve poznate podatke o ovom našem izvornom poljoprivrednom i prehrambenom proizvodu, već ističe ovaj proizvod kao simbol Varaždinštine. Navodi povijesnu važnost uzgoja i nastanak izvornih specijaliteta te u konačnici daje smjernice za očuvanje proizvoda, ideje za obnovu i unaprjeđenje proizvodnje u okviru zelenog poduzetništva, uspostavljanje robne marke na razini EU te obnovu izvornih, tradicijskih i ekoloških proizvoda hrvatske poljoprivrede.