Browsing by Author "Švarc-Gajić, Jaroslava"
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- Bioactive compounds of sweet and sour cherry stems obtained by subcritical water extractionPublication . Švarc-Gajić, Jaroslava; Cerdà, Víctor; Clavijo, Sabrina; Suárez, Ruth; Mašković, Pavle; Cvetanović, Aleksandra; Delerue-Matos, Cristina; Carvalho, Ana; Novakov, VesnaBACKGROUND Sweet cherries (Prunus avium L.) and sour cherries (Prunus cerasus L.) contain substantial amounts of anthocyanins and polyphenolics, and their stems have been used in traditional medicine for centuries. However, comparative data on the composition of sweet and sour cherry stems using the same analytical methodologies are limited. Moreover, there is no data in terms of biological activity of subcritical water extracts of cherry stems. RESULTS AND DISSCUSION Results obtained by using several assays that focused on different mechanisms showed that subcritical water extracts of sour and sweet cherry stems were powerful antiradicals and antioxidants. Anti‐proliferative properties measured by MTT (3‐[4,5‐ dimethylthiazol‐2‐yl]‐2,5 diphenyl tetrazolium bromide) test showed prominent cytotoxicity against different tumor cell lines. Inhibitory concentrations obtained were in the range 8.38–11.40 µg mL‐1. GC–MS (gas chromatography mass spectrometry) analysis showed the presence of alcohols, fatty acids, organic acids and other organic compounds. However, the chemical compositions of the two samples observed were similar, indicating similar chemical composition of sour and sweet cherry stems. CONCLUSION Subcritical water extracts of cherry stem demonstrated excellent biological activity and the potential to be used for pharmaceuticals or supplements due to confirmed high antioxidant, antiradical and antitumor activity.
- Chemical and biological insights on aronia stems extracts obtained by different extraction techniques: From wastes to functional productsPublication . Cvetanović, Aleksandra; Švarc-Gajić, Jaroslava; Zeković, Zoran; Mašković, Pavle; Đurović, Saša; Zengin, Gökhan; Delerue-Matos, Cristina; Lozano-Sánchez, Jesus; Jakšić, AleksandraThe present study aimed to evaluate chemical and biological potential of aronia stems for providing new raw material for food and pharmaceutical industries. Aqueous extracts of aronia stems were prepared by three different techniques (microwave-assisted, ultrasound-assisted and subcritical water extraction). For biological activities, antioxidant, antimicrobial and cytotoxic activities were evaluated. For chemical characterisation, phenolic compounds and essential elements were analysed as well as total phenolic contents. Subcritical water extracts exhibited the strongest antioxidant activity with the highest content of phenolics. Minimum inhibitory concentrations for analysed extracts were in the range from 9.76 to 156.25 μg/mL in antimicrobial assays. The extracts exerted prominent cytotoxicity against different cell lines. Rutin was detected as the major compound in the studied extracts and these extracts were also rich in essential elements. Our study suggested that subcritical water extract of aronia stem could be considered as a new raw material in developing novel functional/industrial products.
- Chemical Characterization and In Vitro Bioactivity of Apple Bark Extracts Obtained by Subcritical WaterPublication . Švarc-Gajić, Jaroslava; Cerdà, Víctor; Delerue-Matos, Cristina; Mašković, Pavle; Clavijo, Sabrina; Suarez, Ruth; Cvetanović, Aleksandra; Ramalhosa, Maria João; Barroso, M. Fátima; Moreira, Manuela; Morais, Simone; Withouck, Hannes; Boeykens, AnnickRecently, the value of wood residues has received increasing attention due to the presence of pharmacologically active compounds. In the present study, apple bark was treated with subcritical water (SWE) with the aim of bioactivity determination and chemical analysis by GC–MS applying two different sample preparation protocols and by HPLC. Extracts were screened for their total antioxidant capacity by means of total phenolic (TPC) and flavonoid contents (TFC), ferric reducing antioxidant power (FRAP) and DPPH-radical scavenging activity (DPPH-RSA). Anti-microbial and anti-proliferative activities of the apple bark subcritical water extracts were also examined. Different lignin and cellulose degradation products were identified by GC–MS, as well as naturally present compounds. Identified compounds encompassed organic and fatty acids, alcohols, sugars, phenol, benzaldehyde, cinnamic acid, cinnamaldehyde and azulene derivatives, as well as other organic compounds. Phenolic profiles of apple bark extracts defined by HPLC–PDA analysis revealed that the main contributors were gallic acid (9.4 ± 0.5 mg/g DW) and catechin (8.3 ± 0.4 mg/g DW). The diversity of the extracts composition supports the fact that this medium is able to extract compounds of different polarities, simultaneously acting as catalyst and reactant. The characterized apple bark extracts demonstrated good antioxidant (TPC = 31.47 ± 1.86 mg GAE/g; TFC = 17.40 ± 1.89 mg EE/g; FRAP = 22.45 ± 2.22 mg AAE/g; DPPH-RSA = 22.57 ± 2.24 mg Trolox E/g DW), antimicrobial (MIC = 19.53–156.25 μg/mL) and anti-proliferative activity (IC50 = 19.88–47.44 μg/mL). The findings of this study showed that SWE can be used as an environmentally friendly and safe technique for the valorization of apple tree wood residues, applicable in food and pharmaceutical industries.
- Chemical composition and bioactivity of oilseed cake extracts obtained by subcritical and modified subcritical waterPublication . Švarc-Gajić, Jaroslava; Rodrigues, Francisca; Moreira, Manuela M.; Delerue-Matos, Cristina; Morais, Simone; Dorosh, Olena; Silva, Ana Margarida; Bassani, Andrea; Dzedik, Valentin; Spigno, GiorgiaRecovery of bioactive compounds from biowaste is gaining more and more interest in circular economy models. The oilseed cakes are usually insufficiently exploited by most technologies since they represent valuable matrices abundant in proteins, minerals, and phytochemicals, but their use is mostly limited to feed ingredients, fertilizers or biofuel production. This study was thus focused on the exploration of new valorization pathways of oilseed cakes by subcritical water, representing a safe and economic alternative in the creation of value chains. Pumpkin, hemp, and flax seed cakes were treated with subcritical water in nitrogen and carbon-dioxide atmospheres, as well as in nitrogen atmosphere with the addition of acid catalyst. The degradation of carbohydrate fraction was studied by quantifying sugars and sugar degradation products in the obtained extracts. The extracts obtained under different conditions were further compared chemically with respect to total phenols and flavonoids, as well as to the content of individual phenolic compounds. Furthermore, the effects of subcritical water treatment conditions on antioxidant, antiradical and cytotoxic properties of thus obtained extracts were defined and discussed.
- Development and Characterization of Functional Cookies Enriched with Chestnut Shells Extract as Source of Bioactive Phenolic CompoundsPublication . Pinto, Diana; Moreira, Manuela M.; Vieira, Elsa F.; Švarc-Gajić, Jaroslava; Vallverdú-Queralt, Anna; Brezo-Borjan, Tanja; Delerue-Matos, Cristina; Rodrigues, FranciscaChestnut (Castanea sativa) shells (CSs), an undervalued agro-industrial biowaste, have arisen as a source of bioactive compounds with promising health-promoting effects. This study attempted, for the first time, to develop a functional food, namely cookies, using a CS extract obtained by an eco-friendly technology (subcritical water extraction). The cookies were characterized regarding their nutritional composition, total phenolic and flavonoid contents (TPC and TFC, respectively), antioxidant/antiradical activities, phenolic profile, and sensory evaluation. The results demonstrated that the CS-extract-enriched cookies were mainly composed of carbohydrates (53.92% on dry weight (dw)), fat (32.62% dw), and fiber (5.15% dw). The phenolic profile outlined by HPLC-PDA revealed the presence of phenolic acids, flavonoids, and hydrolysable tannins, attesting to the high TPC and TFC. The in vitro antioxidant/antiradical effects proved the bioactivity of the functional cookies, while the sensory evaluation unveiled excellent scores on all attributes (≥6.25). The heatmap diagram corroborated strong correlations between the TPC and antioxidant/antiradical properties, predicting that the appreciated sensory attributes were closely correlated with high carbohydrates and phenolic compounds. This study encourages the sustainable recovery of antioxidants from CSs and their further employment as an active nutraceutical ingredient in functional cookies.
- ESG approach in the valorization of cocoa (Theobroma cacao) by-products by subcritical water: Application in the cosmetic industryPublication . Švarc-Gajić, Jaroslava; Brezo-Borjan, Tanja; Dzedik, Valentin; Rodrigues, Francisca; Morais, Simone; Delerue-Matos, CristinaIn this research valorization potentials of cocoa hull extracts in cosmetic industry, following Environmental, Social, and Governance (ESG) criteria, have been investigated and reported, presenting increased value of this biowaste. The extracts of cocoa hull obtained by subcritical water were characterized in respect to chemical composition and certain bioactive properties, and were used to develop functional cosmetic formulation. In this work cocoa hull of cocoa beans originating from different geographical locations (Ivory Coast, Ghana, Togo, Grenada) were extracted by subcritical water to obtain functional extracts rich in valuable compounds. The extracts were characterized in respect to their total proteins (10–27%), total phenols (37–45 mg GAE/g) and total flavonoids (14–21 mg RE/g) contents. In addition, the minerals K (41–60 mg/100 g), Na (0.78–1.17 mg/100 g), and Ca (2.47–5.94 mg/100 g) were also quantified. Antiradical activity against DPPH (IC50 ∼ 11–13 μg/ml) and ABTS (IC50 ∼ 7–9 μg/ml) radicals, as well as total antioxidant activity (∼14–20 mg EAK/100 g DE), were determined and compared for all extracts. The extract with the highest antioxidant and antiradical activity was used for the formulation of a functional cosmetic product – a day cream with sun protective properties and added qualities. The prepared facial cream was analysed in respect to basic quality parameters for cosmetic products, proving the safety of the newly developed product based on subcritical water extracts of cocoa hull. The application of subcritical water extraction, as a green technology, can significantly enhance the ESG development in the cosmetic industry.
- Influence of temperature on the subcritical water extraction of Actinidia arguta leaves: A screening of pro-healthy compoundsPublication . Silva, Ana Margarida; Luís, Ana Sofia; Moreira, Manuela M.; Ferraz, Ricardo; Brezo-Borjan, Tanja; Švarc-Gajić, Jaroslava; Costa, Paulo C.; Delerue-Matos, Cristina; Rodrigues, FranciscaActinidia arguta is a species disseminated in Europe and classified by the Chinese Herbal Medicine as a medicinal plant. The fruit (kiwiberry) has been extensively exploited for multiple purposes, while leaves where discarded. The objective of this study was to evaluate the optimal Subcritical Water Extraction (SWE) temperature (110 °C - 160 °C) of antioxidants and polyphenols from A. arguta leaves. The optimal temperature of extraction was 123 °C, revealing the highest phenolic and flavonoid contents and good scavenging efficiencies against HOCl (IC50 = 17.06 μg/mL) and O2●- (IC50 = 335.2 μg/mL), without toxicity on intestinal cells. The phenolic profile was characterized by high amounts of phenolic acids (e.g., gallic acids), flavanols (catechin) and flavonols (e.g., quercetin-3-O-galactoside). This work allows to conclude that SWE can be a useful extraction technique for the recovery of polyphenolics from A. arguta leaves
- Liquid by-products from fish canning industry as sustainable sources of ω3 lipidsPublication . Monteiro, Ana; Paquincha, Diogo; Martins, Florinda; Queirós, Rui P.; Saraiva, Jorge A.; Švarc-Gajić, Jaroslava; Nastić, Nataša; Delerue-Matos, Cristina; Carvalho, Ana P.Fish canning industry generates large amounts of liquid wastes, which are discarded, after proper treatment to remove the organic load. However, alternative treatment processes may also be designed in order to target the recovery of valuable compounds; with this procedure, these wastewaters are converted into liquid by-products, becoming an additional source of revenue for the company. This study evaluated green and economically sustainable methodologies for the extraction of ω3 lipids from fish canning liquid by-products. Lipids were extracted by processes combining physical and chemical parameters (conventional and pressurized extraction processes), as well as chemical and biological parameters. Furthermore, LCA was applied to evaluate the environmental performance and costs indicators for each process. Results indicated that extraction with high hydrostatic pressure provides the highest amounts of ω3 polyunsaturated fatty acids (3331,5 mg L-1 effluent), apart from presenting the lowest environmental impact and costs. The studied procedures allow to obtain alternative, sustainable and traceable sources of ω3 lipids for further applications in food, pharmaceutical and cosmetic industries. Additionally, such approach contributes towards the organic depuration of canning liquid effluents, therefore reducing the overall waste treatment costs.
- Microwave-assisted extraction of phenolic compounds from Morus nigra leaves: optimization and characterization of the antioxidant activity and phenolic compositionPublication . Radojković, Marija; Moreira, Manuela M.; Soares, Cristina; Barroso, M. Fátima; Cvetanović, Aleksandra; Švarc-Gajić, Jaroslava; Morais, Simone; Delerue-Matos, CristinaBACKGROUND Morus nigra (mulberry) fruit has been reported as a source of bioactive compounds, although information about their leaves is very limited. Usually, they are considered wastes and have been traditionally used only for tea preparation. The main objective of this work was to explore the valorization of mulberry leaves by polyphenols microwave‐assisted extraction (MAE) and characterization of their antioxidant activity and phenolic composition. A 23 factorial design combined with response surface methodology were applied to characterize the effect of main microwave parameters on total phenolic content (TPC). RESULTS The optimized MAE conditions were 20 mL of ethanol:water (1:1; v/v), 120 °C, 28 min, 0.414 g and medium stirring speed. Under these conditions, TPC was 19.7 ± 2.0 mg gallic acid equivalents (GAE) g‐1 dry plant (DP), and antioxidant activity was 15.3 ± 1.0 mg ascorbic acid (AA) g‐1 DP (ferric reduction activity power –FRAP– assay), 18.6 ± 1.3 mg Trolox equivalents (TE) g‐1 DP (2,2‐diphenyl‐1‐picrylhydrazyl –DPPH– assay) and 186 ± 15 mg TE g‐1 DP (oxygen radical absorbance capacity –ORAC– assay). When compared with ultrasound extraction and Pharmacopeia reference method, MAE was more efficient, representing a valuable technology. Of the 13 compounds identified by HPLC, the most abundant were rutin, chlorogenic, β‐resorcylic and caffeic acids. CONCLUSION These results indicate that mulberry leaves are of potential interest for agro‐food industries as a new source of natural antioxidants.
- Mineral Composition of Subcritical Water Extracts of Saccorhiza Polyschides, a Brown Seaweed Used as Fertilizer in the North of PortugalPublication . Soares, Cristina; Švarc-Gajić, Jaroslava; Oliva-Teles, Maria Teresa; Pinto, Edgar; Nastić, Nataša; Savić, Saša; Almeida, Agostinho; Delerue-Matos, CristinaThe present work aimed at studying Saccorhiza polyschides extracts obtained by subcritical water extraction as a potential source of essential macro and trace elements, aiming for its potential application as a biofertilizer. The mineral composition, as well as sulfate, chlorine and iodine, total organic matter, and total nitrogen content, were determined on the extracts obtained from seaweeds harvested during low tide at the northern Portuguese coast. The selected parameters are important for a biofertilizer. Among the macronutrients, the most abundant was K (15.7 ± 0.2 g/L), followed by Na (5.46 ± 0.11 g/L), S (1.52 ± 0.06 g/L), Ca (1.09 ± 0.11 g/L), and Mg (1.02 ± 0.08 g/L). Several important micronutrients (Zn, B, Cl, P, Mo, V, Se, and I) have also been found in the extracts. The total organic matter was 34.1 ± 0.3 g/L. The extracts present low levels of toxic compounds such as Ni, Cd, and Pb. Considering the composition of the obtained extracts, these can find application in the development of fertilization products. The composition of subcritical water extracts of S. polyschides suggests that they may have important characteristics as a biofertilizer and can be an option in biofortification experiments with essential nutrients. The method can be easily scaled up which makes it attractive for agricultural applications.