Blackcurrant Seeds Research Articles

Alginate Films Enriched in Raspberry and/or Black Currant Seed Oils as Active Food Packaging.

Alginate films plasticized with glycerol and enriched in raspberry and/or black currant seed oils were prepared via casting solution techniques. The intention was to create active films for food packaging where antioxidants in a film would deactivate oxidants in a packed product or its surroundings, improving conditions inside packaging and extending the shelf life of such a product. The prepared materials were characterized by physicochemical, spectroscopic, mechanical, water vapor transmission (WVTR), and antioxidant activity analysis. Infrared spectra of the alginate films with oils were similar to those without the additive; the band with a maximum at about 1740 cm-1 stood out. The prepared materials with oils were thicker, contained less water, were more yellow, and were less permeable to water vapor. Moreover, the presence of the oil in the films resulted in a slightly lower Young's modulus and lower stress at break values but higher strain at break. The antioxidant capacity of raspberry seed oil itself was about five times higher than that of black currant seed oil, and a similar trend was noticed for films modified with these oils. The results indicated that both oils could be used as active substances with antioxidant properties in food packaging.

Evaluation of different blackcurrant seed ingredients in meatballs by using conventional quality assessment and untargeted metabolomics

Blackcurrants are sources of phenolic compounds, such as anthocyanins, possessing strong antioxidant, antimicrobial and antifungal activity. Therefore, the addition of different blackcurrant pomace ingredients may affect the overall meat quality. The actual chemical profile and bioactivities of blackcurrant pomace ingredients may strongly depend on its preparation; for instance, in our study the highest values of the in vitro antioxidant capacity were determined for blackcurrant seeds after supercritical CO2 extraction. Starting from these background conditions, in this work, we evaluated the ability of three different concentrations (namely 1, 3, and 5% w/w) of blackcurrant (BC) seeds following EtOH/water extraction (BC-AE), before supercritical fluid CO2 extraction (BC-RS), and after supercritical fluid CO2 extraction (BC-ASC) to affect different quality parameters of pork meatballs. These latter were stored considering three different time-points, namely 1, 3 and 6 days at 4 °C packed under modified atmosphere (i.e., 70% N2 and 30% CO2). Untargeted metabolomics allowed to identify several lipid and protein-related oxidation products involved in redox reactions, such as 13-L-hydroperoxylinoleic acid, (12S,13S)-epoxylinolenic acid, 9,10-epoxyoctadecenoic acid, glutathione, glutathione disulfide, L-carnosine, l-ascorbic acid, and tocotrienols. Besides, multivariate statistics applied on the metabolomics dataset confirmed that the chemical profile of meatballs was an exclusive combination of both BC inclusion levels and type of BC-ingredients considered. Our findings showed that the higher the concentration of BC seed ingredients in meatballs, the lower the cooking loss and the higher the fibre content. Also, all the ingredients significantly affected the colour parameters.

The correlation between nutritional and health potential and antioxidant properties of raw edible oils from cultivated and wild plants

SummaryThe nutritional properties and health potential of oils from 15 various cultivated and wild plants were investigated on the basis of the fatty acids profiles, total carotenoids and tocopherols content, antioxidant properties and health potential indexes such as atherogenicity index (AI). The oil contents of the plants varied between 0.9 g/100 g for lychee seeds and 29.7 g/100 g for borage seeds. The tocopherol content in oils ranged from 0.31 (lingonberry fruits) to 226.23 mg/100 g (hawthorn pulp), carotenoids ranged from 0.36 (borage seeds) to 14.22 mg/100 g (blackcurrant seeds). In four oils (raspberry seed, strawberry seed, lingonberry fruits, blackcurrant seeds) the PUFA contents contributed over 70% of the total fatty acids (FA), which was associated with the best values health potential indexes. It was found that TAC (Total Antioxidant Capacity) can be an indirect measure of the levels of carotenoids and tocopherols in oils. Additionally, a positive correlation between the level of carotenoids and the FA n‐3 was demonstrated. Determining such relationships may facilitate research into new sources of valuable edible oils useful for the production of functional foods, dietary supplements and cosmetics.

Blackcurrant (Ribes nigrum L.) Seeds-A Valuable Byproduct for Further Processing.

The rational exploitation of byproducts is important from the point of view of their potential applicability in various fields. In this study, the possibility of further processing of blackcurrant seeds (BCs), which are a byproduct of fruit processing, was investigated. BCs were used as a material for the extraction of oil on a semi-industrial scale, and the residues were assessed in terms of their potential application in skin care products. Supercritical fluid extraction (SFE) using CO2 at pressures of 230 and 330 bar and extraction temperature of 40 °C was exploited for isolation of oil, and the products were characterised taking into account lipophilic constituents. After 120 min, the oil yields were 19.67% and 20.94% using CO2 at 230 and 330 bar, respectively, which showed that SFE was an effective method on a semi-industrial scale, taking into account the extraction yield. The oils had similar fatty acid compositions with a high percentage of linoleic acid (ca. 43%); however, tocopherols and carotenoids were most abundant in the oil obtained at 230 bar. It was also found that the composition of the SFE oils was comparable with that of cold-pressed oil, which shows that supercritical fluid extraction provides a high-quality product; therefore, it can be an alternative to cold pressing. Furthermore, the chemical compositions of the extracts from the oil isolation residues were established using UPLC-MS, and the impact of the extracts on human skin fibroblasts was assessed using the MTT and NR assays. The quantitative analysis revealed that the residues contained high amounts of polyphenolic acids, including gallic, protocatechuic, and hydroxybenzoic acid derivatives, as well as flavonoids, especially quercetin and kaempferol glucoside. Moreover, it was found that the extracts were nontoxic and exerted a stimulatory effect on cell metabolism. Therefore, they can be a valuable additive to natural plant-based cosmetics. Our results showed that blackcurrant seeds, regarded as a byproduct, can be a valuable material for further use.

Inhibition of Colon Cancer Cells Proliferation and Invasion by Etoposide Loaded on Nano-Suspensions Containing Black Currant Seed and Evening Primrose Oils

Formulating etoposide into a nanoemulsion based on combining two natural oils, Ribes nigrum (black currant) seed oil and organic evening primrose oils may improve its antineoplastic activity in cancer cells. The present study aimed to synthesize, characterize and in vitro evaluate the cytotoxic effect of formulating etoposide-loaded (black currant) seed oil and organic evening primrose oils on Colorectal Carcinoma colon cancer cells. The anti-proliferation and anti-invasion effects of the produced formula on Colorectal Carcinoma were investigated by the cell counting kit-8 and the collagen-based cell invasion assay, respectively. Mitochondrial staining kit, annexin Fluorescein isothiocyanate double staining, and nucleosome detection were used to discriminate the stages of apoptosis. According to the dynamic light scattering results, formulating etoposide-loaded (black currant) seed oil consisted of nanodroplets with z-average diameters of 144.6±5.3 nm and mean surface charge of -0.081±0.001 mV. Only (1.7±1.3) µM of formulating etoposide-loaded (black currant) seed oil was able to cause 50 % reduction in the Colorectal Carcinoma cellular growth which was strikingly lower than that of free- formulating etoposide (18.1±2.5 µM) by around ten-fold. The superior apoptotic effect of Formulating etoposide Ribes nigrum (black currant) seed oil and organic evening primrose oils relative to free- formulating etoposide on the Colorectal Carcinoma cells was ascertained by the enhanced mitochondrial depolarization, higher nucleosomal ratio and increased amount of early and late apoptotic cellular populations. The Formulating etoposide Ribes nigrum (black currant) seed oil and organic evening primrose oils treatment impeded the invasion of colorectal carcinoma cells by (54.8±1.2) %, which was greater than the free- formulating etoposide treatment that deterred only (35.1±1.2) % of the invaded cells. In conclusion, the incorporation of formulating etoposide into a nanoemulsion formulated from the bioactive natural oils potentiates its antitumor activity in colon cancer cells.

New micronutrient biocomponents based on blackcurrant seeds pomace – Bench-scale kinetic studies

In the present work new universal bench-scale plant for biosorption, useful in production of new micronutrient biocomponents, was described. The new installation enabling working in a fixed bed or stirred tank batch mode. Reactors may also be used in serial or parallel mode, which gives many application possibilities. Copper ions were selected as a sorbate for kinetic modelling. The results of the adsorption capacities of Cu(II) were 13.9 mg/g for fixed bed and 12.8 mg/g for stirred tank. During biosorption of Cu(II) ions from aqueous solution ion exchange and release of Ca(II), K(I), Mg(II), and Na(I) were observed. For kinetics description of stirred tank process pseudo-1st-and pseudo-2nd order models were used. For fixed bed process the Thomas, Yoon-Nelson, Adams-Bohart and Wolborska models were used. The use of blackcurrant seed residues as biosorbents enables the generation of new products from waste biomass, which can become an alternative to the traditional fertilizers with microelements. The presented technology is an attempt to reduce environmental impact of the conventional micronutrient fertilizers, which contain toxic chelators such as EDTA. Minimization of waste and maximization of product output makes it an efficient tool supporting cleaner production.

Supercritical Fluid Extraction of Berry Seeds: Chemical Composition and Antioxidant Activity

The influence of supercritical fluid extraction (SFE) and solvent extraction of oils from cloudberry, bilberry, and black currant seeds on the yield, chemical properties, and recovery of antioxidant compounds was investigated. SFE was performed for 1 h at 350 bar and at 50°C and 80°C. Fatty acids, vitamin E, carotenoids, and free radical-scavenging activity (DPPH) were assayed. SFE at 80°C resulted in higher oil yields for cloudberry and black currant seeds. The oils were rich in polyunsaturated fatty acids (PUFAs) (66.8%–75.9% w/w), with high percentages of linoleic and α-linolenic acids. The black currant seed extracts had the highest concentrations of vitamin E (range, 113.0–241.8 mg/100 g oil) and carotenoids (range, 11.5–32.3 mg/100 g oil) and the highest antioxidant activity. The cloudberry seed oils also had high antioxidant content and activity. These findings indicate the potential of SFE for the recovery of PUFA and antioxidant compounds in berry by-products.

Phytochemical Content, Oxidative Stability, and Nutritional Properties of Unconventional Cold-pressed Edible Oils

Plant oils are a good source of compounds that decrease the risk of some diseases. Growing consumer awareness has led to more interest in natural cold-pressed plant oils, which are often considered functional foods. Many unconventional edible plant oils are available on the market, but their quality and composition are often unknown. The aim of this study was to compare the nutritional value and quality of sixteen unconventional cold-pressed edible oils. The acid value (AV), peroxide value (PV), oxidative stability, fatty acid composition, phytosterol content, and tocochromanol content were measured for both fresh and stored oils. The nutritional quality indexes were also calculated. Cluster analysis of all factors showed that the oils fell into two groups: the first contained argan oil, pine oil, apricot kernel oil, avocado fruit oil, and macadamia nut oil; these had high levels of saturated and monounsaturated fatty acids and low amounts of phytosterols and tocochromanols. The second group included oil from dill seeds, milk thistle seeds, parsley seeds, watermelon seeds, safflower, poppy seeds, black cumin seeds, hemp, blackcurrant seeds, borage, and wheat germ. The highest tocochromanol and phytosterol content were observed in wheat germ and blackcurrant seed oil, and the lowest in black cumin and dill seed oil.

Effect of addition of plant extracts on the durability and sensory properties of oat flake cookies

Fragile cookies are one of the most popular high-fat cereal products. Products of this type with added oat flakes may be labeled with a nutrition claim and may be included in functional foods. Fat from oat flakes and which is a recipe ingredient of cookies undergoes degradation during storage which leads to the formation of harmful oxidation products and sensory changes in products. The aim of this study was to determine the effect of green tea extracts (GT), blackcurrant (BC) seeds and nettles (N) on the rate of fat degradation in cookies with oat flakes and their sensory properties. In this work, the antioxidant effect of natural extracts antioxidant on oxidative stability of fat extracted from cookies was evaluated by differential scanning calorimetry (DSC) and by peroxide value, anisidine value and specific UV extinctions (K value). Moreover, cookies were subjected to sensory analysis and to instrumental measurements of color changes. The extracts used in the study had an influence on the rate of fat oxidation changes in cookies after baking and also during 3 months of storage. The most effective fat degradation inhibitor was the extract with GT in 1% addition, while the most unfavorable change was observed in fat with the lowest addition of N extract (0.5%). It was observed that the applied plant extracts did not significantly reduce the sensory properties of the products. The most desirable products were the cookies with 1% GT extract and those with the highest proportion of blackcurrant seed extract (1.5%).

Pilot Plant Conversion of Blackcurrant Seeds into New Micronutrient Fertilizer Biocomponents via Biosorption

A new approach for micronutrient fertilizer biocomponent production based on blackcurrant seeds is presented. Blackcurrant seeds constitute a by-product from the production of jellies, jams, and juices. New environmental-friendly fertilizers with micronutrients were produced in the pilot plant as alternative sustainable fertilizers to conventional options. Post-extraction residues, obtained after supercritical CO2 extraction was conducted on blackcurrant seeds, were used. In each process, 15 kg of biosorbent was used. Good sorption capacity was achieved (6.48 mg/g for Zn(II), 13.9 mg/g for Cu(II) and 5.88 mg/g for Mn (II)). The adsorption kinetics was described using different kinetic models; the most suitable were the Nelson-Yoon and Thomas models. The new preparation has application-friendly form (micro-granules) and is nontoxic. For a dose of 2.5 kg of zinc, 1 kg of manganese, and 0.5 kg of copper per hectare (often used in vegetable fertilization), approximately 600 kg of mixed end product is required. The cost of fertilization with current scale technology will be about four times higher than that of conventional technology (including depreciation of equipment), but with process scale-up, it is possible to reduce costs even twice over.

Biofortification of maize grains with micronutrients by enriched biomass of blackcurrant seeds

Abstract Effect of the application of blackcurrant seed post-extraction residues (BS) enriched via biosorption with Zn(II), Mn(II) and Cu(II) was examined in field tests on maize. As a nominal dose (100%), 2.5 kg of zinc, 1 kg of manganese and 0.5 kg of copper per hectare, were applied. The preparation was applied, also, in higher doses (150%, 200%). Crop yield and quality were assessed and multielemental analysis of grains was conducted. Grain yield obtained for maize treated with different doses of micronutrients (7.3 and 7.2 Mg ha-1 for BS 100% and BS 200%, respectively) was higher than in control group (6.2 Mg ha-1) and similar to a commercial reference product (7.1 Mg ha-1). Bioavailability of micronutrients from BS was shown to be higher than from reference commercial fertilizer. The highest content of micronutrients delivered to plants was observed for groups fertilized with BS in nominal dose of micronutrients (1.79, 7.08 and 28.55 mg kg-1 for Cu, Mn and Zn, respectively). The content of each micronutrient was 5.6% (Cu) 12.1% (Mn) and 12.6% (Zn) higher than in untreated group and 8.9% (Cu) 9.7% (Mn) and 8.7% (Zn) higher than commercial reference micronutrient fertilizer. New biocomponents are cheap and biodegradable carriers of nutrients which can be released in controlled way.

Enhancement of nutritionally significant constituents of black currant seeds by chemical elicitor application

Black currant seeds are obtained as a residue during juice production. Black currant seed oil contains high amounts of nutritionally desirable constituents such as γ-linolenic acid (GLA), α-linolenic acid (ALA) and stearidonic acid (SA), as well as certain phenolic acids, which act as natural antioxidants. Fatty acids and phenolic acids of seeds from black currant cultivars after elicitation with methyl jasmonate (MJ) were examined. GLA contents around 25% with respect to total fatty acid content were measured in seeds after pre-harvest treatment of black currants with 0.02mM MJ in 0.05% Tween-20. High GLA samples also exhibited high SA content (higher than 10% with respect to total fatty acid content); however, ALA dropped (from 16% to 10%). High GLA content seeds also showed increased contents of gallic, caffeic, p-coumaric and ferulic acids. In particular, seeds from 0.02mM MJ treated Ben Hope black currants exerted contents of gallic, caffeic, p-coumaric and ferulic acids of 201.4, 125.9, 201.3 and 112.5μgg−1vs 124.3, 58.6, 165.4 and 95.8μgg−1 measured in seeds from untreated Ben Hope black currants. Comparable results were obtained for Ben Alder and Ben Gairn berries. Chemical elicitation with 0.02 MJ is proposed as an industrial practice in such a way that, after consideration of quality issues, it would be obtained high added value black currant seeds.

The effect of selected supercritical CO2 plant extract addition on user properties of shower gels

Abstract The formulations of washing cosmetics i.e. shower gels, containing extracts obtained during supercritical CO2 extraction process as active ingredient, were developed. The subject of the study was the analysis of the physicochemical and user properties of the obtained products. In the work supercritical CO2 extracts of black currant seeds, strawberry seeds, hop cones and mint leafs were used. The formulation contains a mixture of surfactants (disodium cocoamphodiacetate, disodium laureth sulfosuccinate, cocoamide DEA, cocoamidepropyl betaine, Sodium Laureth Sulfate). Various thickener agents were applied to the obtained desired rheological properties of the cosmetics. Among others, sorbitol acetal derivatives, methylhydroxypropylcellulose and C10-30 alkyl acrylate crosspolymer were used. For stable products, the effect of extracts addition (black currants seeds, strawberries seeds, mint and hops, obtained from supercritical CO2 extraction process) on the cosmetics properties, such as pH, viscosity, detergency and foam ability, were determined. The obtained results showed that the extracts could be used as components of shower gels.

Physicochemical Characteristics of Cereal Extrudates with Different Levels of Defatted Blackcurrant Seeds

AbstractThe aim of this study was to determine the effects of different proportions of defatted blackcurrant seeds on the nonstarch polysaccharide, sugar, starch and vitamin C content and the basic physical properties of cereal extrudates. The analyzed extrudates were based on cornmeal, which was partly replaced with blackcurrant seeds in proportions of 10, 30 and 50%. It was observed that the addition of seeds caused elevation in fiber and hemicelluloses compared with the control; the beta‐glucan content in all analyzed samples was negligible. The vitamin C content in extrudates with seeds was several times higher, but the amount of starch decreased and the level of sugar increased in comparison with control. Extrudates with seeds added were characterized by higher water‐binding capacity and solubility in comparison with a control (with the exception of that with 50% seeds). It was shown that the addition of seeds increased the density and reduced the expansion of extrudates.Practical ApplicationsThe physicochemical characteristics of cereal extrudates were highly dependent on the proportion of defatted blackcurrant seeds. The study showed a correlation between the physical parameters and the chemical composition of the snacks. The addition of defatted blackcurrant seeds to cereal snacks to a proportion of 10% resulted in a product with high expansion, low density, good solubility and water‐binding properties, and enhanced levels of pro‐health components.

Chemical Composition of Currant Seed Extracts and Their Protective Effect on Human Lymphocytes DNA

On the basis of LC/UV/MS analysis, 35 compounds from the extracts of seeds of black, red, and white currants (2 cultivars of each) were identified. Black currants cultivars contained protocatechuic acid and p-hydroxybenzoic acid, and traces of nitril containing phenolic acids. The presence of synapoyl glucoside was characteristic for cv. Malling Jewel. Sesquiterpenoid glycosides and carboxymethylindol glycosides were present mainly in white and red currant cultivars. Blackcurrant seeds contained higher amounts of flavonoids, especially rutin, isoquercetin, and taxifolin. The currant seed extracts were tested for in vitro protective effect on chromosome aberrations in peripheral human lymphocytes using cytochalasin-B blocked micronucleus (CBMN) assay. The frequency of MN was scored in binucleated cells, and the cultivars of black currants showed the best antioxidant potential. At a concentration of only 0.17 mg/mL, extract of the seed cv. Malling Jewel effected a decrease in the frequency of MN of 60% compared with control cell cultures. Our results provide evidence of protective effects of currant seed extracts and isolated pure compounds on cytogenetic damages in human lymphocytes. Thus, currant seed extracts could exert beneficial effects in quite a few diseases, for many of the biological actions have been attributed to their antioxidant properties.

THE INFLUENCE OF ADDITION OF DEFATTED BLACKCURRANT SEEDS ON PRO-HEALTH CONSTITUENTS AND TEXTURE OF CEREAL EXTRUDATES

Extrudates used in the study were prepared on the base of cornmeal (100%) – control, which was in 10, 30 and 50% replaced by defatted seeds of blackcurrant, which were a by-product of supercritical fluid extraction, used for oil production. The aim of the study was to check the influence of the level of defatted blackcurrant seeds, on texture and chemical composition of the obtained extrudates. Special attention was paid to pro-health constituents, i.e., dietary fiber, polyphenols, flavonoids and anthocyanins. The addition of defatted seeds resulted in an increase of polyphenol content, and antioxidant activity, and the rise in the level of flavonoids and soluble dietary fiber as compared with control. The enrichment of extrudates in pro-health components, as well as improvement of sensory score, suggests that 10% addition of defatted blackcurrant seeds is a suitable level for preparation of extruded fruit-cereal snacks. PRACTICAL APPLICATIONS The study demonstrates that defatted blackcurrant seeds could be a good, natural source of bioactive components in cereal snacks produced by extrusion. The suggested level of this component, optimal from sensory and dietary point of view, is 10%.

DEFATTED STRAWBERRY AND BLACKCURRANT SEEDS AS FUNCTIONAL INGREDIENTS OF GLUTEN‐FREE BREAD

ABSTRACTDefatted blackcurrant (DS‐BC) and strawberry (DS‐ST) seeds were used as a dietary supplement in gluten‐free bread. Addition of 15% DS‐BC or DS‐ST significantly modified viscoelastic properties of the dough and reduced the values of consistency coefficients and flow indices. Texture analysis proved the important role of seed type and level, only in establishing hardness, chewiness and gumminess. The hardness of supplemented bread was diminished in comparison with control, and the influence of DS‐ST was more pronounced than that of DS‐BC. The applied functional ingredients significantly influenced color parameters of the crumb, by diminishing the values of L* and b* (in case of DS‐BC) and increasing a*. The maximum addition of 5% DS‐BC or 10% DS‐ST had no negative impact on sensory evaluation of the obtained bread, but resulted in a significant rise of dietary fiber, protein and polyphenols.PRACTICAL APPLICATIONSPomace is used mainly for stock feeding, and in Poland, approximately 12% of produced pomace is composted; however, it could become a valuable component of food products because of significant content of dietary fiber, protein, minerals and bioactive compounds. Significant amounts of pomace originate from the production of oils from the seeds of berries, because lipids constitute only a small part of the whole fruit.The results prove that defatted strawberry and blackcurrant seeds could be used in bakery industry as functional ingredients of gluten‐free breads (which are usually lower in nutritional value in comparison with traditional products) without deterioration of their sensory quality, which is very important in treatment of celiac disease (patients have to follow rigorous gluten‐free diet). The applied functional ingredients significantly increased the levels of protein and dietary fiber, as well as polyphenols in such breads.

Antioxidant activity of blackcurrant seeds extract and rosemary extracts in soybean oil

The objective of this research was to investigate the antioxidative properties of extract from blackcurrant seeds (BCSs) and commercially available rosemary extracts (Stabiloton OS, oil-soluble and WS, water soluble) in soybean oil (SO). The antioxidant activity of plant extracts was compared with those of α-tocopherol and butylated hydroxytoluene (BHT). The results of present research reveal differentiation of action of investigated extracts toward primary (peroxide value (PV), conjugated dienes (CDs)) and secondary (measured as anisidine value (AV), hexanal) oxidation products in SO. WS and OS rosemary extracts show high efficiency in delaying primary and secondary oxidative changes. BCSs extract markedly retards oxidation, nevertheless its activity falls down with formation and succeeding deterioration of primary products. Although the use of BCSs, residues of fruit processing, as a source of antioxidants would be reasonable because of economic and environmental reasons, it may be limited by low activity toward secondary oxidation products in certain lipid substrates. Taking primary oxidative changes into consideration, all extracts studied perform better than used standard antioxidants – BHT and α-tocopherol.

Characterization of Canadian Black Currant (Ribes nigrum L.) Seed Oils and Residues

The seeds from five black currant (Ribes nigrum L.) cultivars grown in western Canada were evaluated for their oil content, fatty acid and triacylglycerol (TAG) composition, and tocopherol and phytosterol profiles and contents. Moreover, polyphenolic compounds and antioxidant activity in the seed extracts remaining after oil extraction were determined. Oil contents of black currant seeds ranged from 27 to 33%. The gamma-linolenic acid content varied significantly among the cultivars (from 11% for Ben Conan to 17% for Ben Tirran). Among the 44 TAGs identified, LLalphaLn, alphaLnLgammaLn, and PLgammaLn (where L = linoleoyl, alphaLn = alpha-linolenoyl, gammaLn = gamma-linolenoyl, and P = palmitoyl) were the predominant ones. Black currant seed oil was a good source of tocopherols (1143 mg/100 g of oil on average) and phytosterols (6453 mg/100 g of oil on average). Quercetin-3-glucoside and p-coumaric acid were the main phenolic components in the seed residues. The high concentration of flavonols and phenolic acids was correlated with a high antioxidant activity of seed residue (average ABTS value of 1.5 mM/100 g and DPPH value of 1.2 mM/100 g). The data obtained from this study indicate that Canadian black currant seed oil is a good source of essential fatty acids, tocopherols, and phytosterols. Extraction of phenolic antioxidants from the seed residues even allows the recovery of additional valuable components from the byproduct of fruit processing.

Regioisomeric Structure Determination of α- and γ-Linolenoyldilinoleoylglycerol in Blackcurrant Seed Oil by Silver Ion High-Performance Liquid Chromatography and Mass Spectrometry

Gamma-linolenic acid (Gla) and oils containing Gla have evident positive effects on a variety of disorders, and therefore, the structure of triacylglycerols (TAGs) containing Gla is of special interest. The regioisomeric structures of TAGs 18:3(n-3)/18:2/18:2 (Ala/L/L) and 18:3(n-6)/18:2/18:2 (Gla/L/L) in blackcurrant seed oil were determined by Ag-HPLC/APCI-MS and Ag-HPLC/ESI-MS/MS techniques. In the latter, silver ion adducts were prepared by adding silver nitrate to the postcolumn flow. A new Ag-HPLC solvent system containing nonchlorinated solvents for the separation of Gla- and Ala-containing TAGs is introduced. Ag-HPLC separation of Ala/L/L and Gla/L/L was sufficient and regioisomers sn-LnLL + sn-LLLn and sn-LLnL (Ln, linolenic acid) could be differentiated well with the MS methods used. No discrimination was made between the sn-1 and sn-3 positions. The results show that the methods used are suitable to discriminate and determine the regioisomeric structure of TAGs. The regioisomeric structure of TAG with the fatty acid combination Gla/L/L in blackcurrant seed oil was considered to be practically random (32.7-37.8% of sn-LGlaL). In the fatty acid combination Ala/L/L, the regioisomeric structure is nonrandom (7.3-12.1% of sn-LAlaL) with Ala preferentially in a primary position. It can be concluded that the positional distribution of Ala and Gla is different in Ln/L/L TAGs of blackcurrant seed oil.