Impact of defatting process on antioxidant potential of grape seeds

Grape seeds contain a wide range of phenolic compounds responsible for its health promoting effects. Interest for grape seed utilization has increased significantly along with a growing recognition that present biologically active compounds were not completely isolated during the extraction process. Numerous studies have been conducted in order to achieve the best extraction recovery. Nevertheless, there is still a question concerning the pretreatment of grape seeds. The aim of the present study was to investigate the impact of defatting process on total polyphenol content and antioxidant activity of grape seed extracts. For that purpose seeds were obtained from eight different grape varieties. Extraction with 70 % ethanol was performed on both, crude and defatted seeds (lipid fraction was removed by Soxhlet method of extraction). Determination of total phenolic content (TPC) was done using Folin-Ciocalteu assay. Antioxidant activity was investigated through four different tests (FRAP, CUPRAC, DPPH and ABTS) and obtained results were combined in unique Antioxidant Composite Index (ACI). TPC values ranged from 50.48 to 121.06 and from 38.04 to 108.17 mg GAE/g dry weight for crude and defatted grape seed extracts, respectively. Higher phenolic content determined in extracts obtained from crude seeds could be explained by the presence of lipophilic biologically active compounds in non-removed lipid fraction. Discrepancies between varieties are presumably present due to different morphological properties of seeds, environmental and agricultural conditions. Concerning antioxidant activity, all tests were significantly correlated with TPC, suggesting the strong contribution of phenolic compounds to this biological activity.Nutraceuticals in balancing redox status in ageing and age-related diseases WGs Meeting of the NutRedOx COST Action CA16112 Belgrade, March 2-3, 202

Nutraceutici u prevenciji i tretmanu COVID-19

The immune system defends the host from many pathogen- ic microorganisms such as viruses, bacteria, parasites and fungi, including a large number of specific cell types, inter- related molecules, and biological responses. Due to infec- tions, heightened immune system activity is accompanied by expanded metabolic activities, requiring appropriate energy supply, precursors for biosynthesis and regulatory molecules. Numerous vitamins and minerals play a crucial role in supporting body’s immunity and fighting against viral infections. Other bioactive compounds like omega-3 fatty acids, probiotics and antioxidants (alpha-lipoic acid, quercetin) are also important in the immune response. CO- VID-19 may develop mild symptoms to severe damage of the respiratory epithelium followed by a cytokine storm. Many studies show that vitamin C, vitamin D, zinc and selenium are critical in defending against SARS-CoV-2 infection. Intestinal dysbiosis is a feature of many infectious diseases, including COVID-19, so dietary approaches to establishing a healthy microbiota are essential for improving immune function. This paper reviews the data on the roles and potential effectiveness of selected nutraceuticals in the prevention and treatment of COVID-19.Imunski sistem štiti organizam od brojnih patogena (bakterija, virusa, gljivica, parazita) uključujući veliki broj specijalizovanih tipova ćelija, komunikacionih molekula i funkcionalnih odgovora. Pojačana aktivnost imunskog si stema usled infekcija praćena je povećanim metaboličkim aktivnostima, što zahteva izvore energije, supstrate za biosintezu i regulatorne molekule. Brojni vitamini i minerali imaju ključnu ulogu u podršci imunskom sistemu i smanjenju rizika od infekcija. Ostale bioaktivne komponente kao omega-3 masne kiseline, probiotici i antioksidansi (alfa-lipoinska kiselina, kvercetin) takođe su od značaja u imunološkom odgovoru. COVID-19 karakterišu kliničke slike od blagih simptoma do teške infekcije respiratornog epitela praćene citokinskom olujom. Pokazano je da starije osobe sa hroničnim bolestima imaju smanjenu aktivnost odbrambenog sistema i neadekvatan nutritivni status, zbog čega postoji veći rizik za pojavu fatalnih ishoda. Ispitivanja ukazuju da su vitamin C, vitamin D, cink i selen posebno važni u odbrani od infekcije SARS-CoV-2. Disbioza creva je karakteristika mnogih zaraznih bolesti uključujući COVID-19, zato su dijetetski pristupi za uspostavljanje zdrave mikrobiote važni u poboljšanju imunoloških funkcija. U ovom radu prikazan je pregled literature o ulozi i potencijalnoj primeni odabranih nutraceutika u prevenciji i tretmanu COVID-19

Nusproizvodi agro-industrije kao izvor održivih sastojaka za proizvodnju funkcionalne hrane i nutraceutika

The disposal of waste generated in the agri-food industry is one of the greatest challenges in achieving sustainable development. Although agri-food residues are a potential source of bioactive compounds with proven health benefits, they are largely unused and disposed of as organic waste. The recovery of bioactive compounds from agri-food waste to obtain products with high biological value, such as functional foods and nutraceuticals, is an idea that stems from the concept of bioeconomy and combines environmental issues with economically viable production. Some of the main agri-food wastes in Serbia that have the potential to be recycled into value-added products are apple, plum, grape, tomato, and beet pomace, and oilseed cakes. Bioactive compounds isolated from these wastes include polyphenols, fibers, essential fatty acids, minerals, various volatiles and pigments. This article focuses on the most common food wastes and the potential reuse of these undervalued material to produce value-added products such as functional foods, nutraceuticals or food additives.Odlaganje otpada koji nastaje u prehrambenoj industriji jedan je od najvećih izazova u postizanju održivog razvoja. Iako su nusproizvodi koji nastaju u prehrambenoj industriji potencijalni izvor bioaktivnih jedinjenja sa dokazanim pozitivnim zdravstvenim efektima, oni se uglavnom odlažu kao organski otpad. Iskorišćenje bioaktivnih jedinjenja iz ovih nusproizvoda u cilju dobijanja proizvoda sa dodatom nutritivnom i biološkom vrednošću, kao što su funkcionalna hrana i nutraceutici, ideja je koja proizilazi iz koncepta bioekonomije i kombinuje ekološki aspekt sa ekonomski održivom proizvodnjom. Neki od glavnih nusproizvoda koji se generišu u Srbiji sa potencijalom da se iskoriste u proizvodnji proizvoda sa dodatom vrednošću su trop jabuke, trop šljive, komina grožđa, trop paradajza, uljane pogače i dr. Bioaktivna jedinjenja izolovana iz ovih otpada uključuju polifenole, peptide, vlakna, esencijalne masne kiseline, minerale, različite isparljive materije i pigmente. Ovaj članak se fokusira na najčešće otpade prehrambene industrije i potencijalnu ponovnu upotrebu ovog još uvek neiskorišćenog otpadnog materijala za proizvodnju proizvoda sa dodatom vrednošću kao što su funkcionalna hrana, nutraceutici ili aditivi

Dijetarni faktori i tiroidna disfunkcija

Besides iodine deficiency, autoimmune Hashimoto thyroiditis is the leading cause of hypothyroidism globally, characterized by the increased titer of thyroid autoantibodies and destruction of thyroid cells. Graves' disease is the most common etiology of hyperthyroidism worldwide. Patients with thyroid dysfunction often require dietary modifications. Popular interventions include supplementation with certain vitamins and minerals, as well as trace elements such as iodine and selenium. The intake of food containing goitrogens should be limited. Goitrogens are substances of plant origin that interfere with the production of thyroid hormones, increasing the risk for goiter and hypothyroidism. The primary dietary sources of goitrogens are cruciferous vegetables, soy products, starchy plants, and some fruits. Beyond essential nutrients, there has been an increasing interest in using specific nutraceuticals, including myoinositol, L- carnitine, melatonin, and resveratrol, as potential preventive and therapeutic agents in thyroid diseases. Even though current evidence promotes some beneficial outcomes of these nutraceuticals, further investigations are needed to clarify dose-dependent effects, duration of supplementation, combination in different clinical settings, and the exact mechanism of their action in thyroid disorders.Pored nedostatka joda, najčešća etiologija hipotireoze u razvijenim zemljama je Hašimoto tireoiditis, koji karakteriše povišen nivo serum autoantitela i limfocitna infiltracija štitaste žlezde. Grejvsova bolest je vodeći uzrok hipertireoza na globalnom nivou. Pacijenti sa oboljenjem štitaste žlezde često zahtevaju modifikaciju dijetarnog režima. Popularne intervencije uključuju suplementaciju određenim vitaminima, mineralima i mikroelementima kao što su jod i selen. Preporučuje se ograničen unos namirnica koje sadrže goitrogene supstance jer ometaju normalnu sintezu tiroidnih hormona, povećavajući rizik za nastanak strume i hipotireoze. Primarni izvori goitrogena u ishrani su kruciferno povrće, proizvodi od soje, skrobne biljke i pojedine vrste voća. Osim esencijalnih nutrijenata, postoji sve veće interesovanje za primenu specifičnih nutraceutika u prevenciji i koterapiji bolesti štitaste žlezde, kao što su mioinozitol, L-karnitin, melatonin i rezveratrol. Trenutni dokazi ukazuju na moguće promotivne efekte ovih jedinjenja u oboljenjima štitaste žlezde. Potrebna su dalja ispitivanja koja bi pratila uticaj doze i dužine suplementacije nutraceutika i potvrdila tačne mehanizme njihovog delovanja u poremećajima funkcije štitaste žlezde

Optimization of Extraction and HPLC–MS/MS Profiling of Phenolic Compounds from Red Grape Seed Extracts Using Conventional and Deep Eutectic Solvents

Winemaking generates large quantities of grape waste consisting of seeds, skin and stalks. Given that grape seeds are a rich source of different bioactive compounds, the main goal of this research was to optimize grape seed phenol extraction using a Box–Behnken design. The following conditions were derived from the optimization process: sample:solvent ratio of 1:10 w/v, extraction time of 30 min and extraction temperature of 50 °C. In addition, a sustainable (green) approach for obtaining extracts was developed by comparing choline chloride:citric acid-ChCit (natural deep eutectic solvent (NADES)) and ethanol extraction methods with respect to phenol profiles and antioxidant activity. This study was conducted on seeds from eight different red grape varieties. Phenolic acids, flavan-3-ols and procyanidins were characterized using HPLC–MS/MS, and the concentration of procyanidin B1 was above 1 mg/g of dry weight in all analyzed samples. The contents of all phenol classes and antioxidant activities were found to not differ significantly between the solvents, but NADES was found to offer valuable advantages. Importantly, ChCit showed a strong affinity toward procyanidins and a strong correlation between antioxidant activity and quantified phenolic compounds

Antioxidant activity of selected spices from Serbian market

Začini su aromatični delovi začinskih biljaka, karakterističnog mirisa i uku- sa, koji se dodaju tokom pripreme hrane radi postizanja odgovarajućih organoleptičkih osobina, kao i zbog produženja roka trajanja namirnica. S obzirom na to da predstavljaju izvore prirodnih antioksidanasa, začini se smatraju i funkcionalnim sastojcima hrane. Osnovni cilj ovog rada jeste analiza sadržaja ukupnih polifenola i fl avonoida odabranih začina sa na- šeg tržišta, kao i komparativna procena njihove antioksidativne aktivnosti. Istraživanje je sprovedeno na komercijalno dostupnim uzorcima deset ra- zličitih vrsta začinskog bilja. Nakon ekstrakcije etanolom, sadržaj ukupnih polifenolnih jedinjenja (Total Polyphenol Content, TPC), kao i sadržaj fl a- vonoida (Total Flavonoid Content, TFC) određen je spektrofotometrijskim metodama. Procena antioksidativnog potencijala izvršena je korišćenjem tri različita testa (FRAP, DPPH, ABTS). Na osnovu dobijenih rezultata, račun- skim putem određene su vrednosti antioksidativnog kompozitnog indeksa (ACI). Najveći sadržaj TPC utvrđen je za cimet (61,3 ± 3,1 mg GAE/g), slede ruzmarin (30,2 ± 3,6 mg GAE/g) i origano (21,0 ± 0,8 mg GAE/g), dok je naj- manji sadržaj bio prisutan u uzorku vlašca (4,3 ± 0,0 mg GAE/g). Sadržaj TFC kretao se u rasponu od 3,2 ± 0,4 μmol CE/g (kim) do 133,7 ± 6,1 μmol CE/g (cimet). U pogledu antioksidativnog potencijala, sva tri testa su pokazala konzistentne rezultate. Utvrđena je statistički značajna povezanost između sadržaja TPC i ACI vrednosti (r= 0,976; p< 0,01). Na osnovu dobijenih rezul- tata može se zaključiti da cimet, ruzmatin i origano predstavljaju bogat izvor polifenolnih jedinjenja i poseduju izražen antioksidativni potencijal.Spices are aromatic parts of herbs with characteristic smell and taste. They are added to food in order to achieve the appropriate organoleptic proper- ties, as well as to extend their shelf life. Since they are sources of natural an- tioxidants, spices are considered as functional food ingredients. The main goal of this research was determination of total polyphenol and fl avonoid content in selected spices from our market and comparative assessment of their antioxidant activity. The study was conducted on ten different commercial samples of herbs. After extraction with ethanol, total polyphe- nol content (TPC), and total fl avonoid content (TFC) were determined by spectrophotometric methods. Evaluation of antioxidant potential was carried out using three different tests (FRAP, DPPH, ABTS). Based on these re- sults, values of antioxidant composite index (ACI) was determined by com- putation. The highest content of polyphenolic compounds was found for cinnamon (61.3±3.1 mg GAE/g), followed by rosemary (30.2±3.6 mg GAE/g) and oregano (21.0±0.8 mg GAE/g), while the lowest content showed shallot (4.3±0.0 mg GAE/g). The content of total fl avonoids ranged from 3.2 μmol CE/g (cumin) to 133.7 μmol CE/g (cinnamon). When it comes to antioxidant potential, all three tests showed consistent results. A statistically signifi cant correlation was fi gured out for total polyphenol content and ACI values (r = 0.976, p<0.01). Based on obtained results, it can be concluded that cinna- mon, rosemary and oregano are the rich sources of polyphenol compounds and have conspicuous antioxidant potential

Raznolikost hemijskog sastava ulja dobijenog iz semenki različitih sorti grožđa

Wine industry generates enormous quantities of solid organic waste consisted of stems, skins and seeds. Grape seeds are considered the most valuable part of a pomace, since it is rich in oil and containing numerous bioactive compounds. Grape seed oil (GSO) composition depends mainly on grape variety, but also on environmental factors and maturation degree. The aim of this study was to investigate the diversity of chemical composition among seed oils obtained from different grape varieties. Eight varieties were collected from the same wine region and at the same maturity phase. Investigation of fatty acid composition was done using GC/FID, while HPLC/FD was employed for vitamin E analyses. Linoleic acid was the most abundant in all samples, followed by oleic acid. Saturated fatty acids, such as palmitic and stearic acid, were also present (up to 20 % of the total fatty acid methyl esters). Vitamin E concentrations were significantly affected by grape variety (p<0.01). α-tocopherol was found in high concentration in all samples. GSO from Shiraz variety had about 25 mg α-tocopherol per kg of oil, while Gamay GSO contained more than six times less amounts of this vitamin E isoform. Sum of β and γ tocopherol also varied considerable, although Shiraz again stood out with the highest content. Finally, δ tocopherol was found in four varieties, in minor quantities. Generally, considering variety diversification on vitamin E composition of GSO, investigations that will include as much varieties as possible, are needed to single out ones with the highest bio-oil potential.Industrija vina ostavlja za sobom ogromne količine čvrstog organskog otpada koji se sastoji od peteljki, pokožice i semenki grožđa. Semenke se smatraju najvrednijim delom komine, jer su bogate uljem i sadrže brojna bioaktivna jedinjenja. Sastav ulja iz semenki grožđa zavisi pre svega od sorte vinove loze, ali i od faktora sredine i stepena zrelosti ploda. Cilj ovog rada bilo je ispitivanje raznolikosti hemijskog sastava ulja dobijenog iz semenki različitih sorti grožđa. U tu svrhu, prikupljeno je osam sorti u istoj fazi zrelosti i iz istog vinskog regiona. Ispitivanje sastava masnih kiselina vršeno je korišćenjem GC/FID, dok je HPLC/FD korišćen za analizu koncentracije vitamina E. Linolna kiselina je bila najzastupljenija u svim uzorcima, zatim oleinska kiselina. Zasićene masne kiseline, kao što su palmitinska i stearinska kiselina, takođe su bile prisutne (do 20 % od ukupnih metil estara masnih kiselina). Sorta vinove loze je značajno uticala na sadržaj vitamina E (p<0,01). α- tokoferol je pronađen u visokim koncentracijama u svim uzorcima. Ulje iz semenki sorte Širaz sadržalo je oko 25 miligrama α-tokoferola po kilogramu, dok je u ulju sorte Game kvantifikovana šest puta manja koncentracija ove izoforme vitamina E. Zbir β i γ tokoferola takođe je značajno varirao, iako se Širaz ponovo istakao sa najvećim sadržajem. δ tokoferol je pronađen u ulju četiri sorte, u manjim količinama. Generalno, s obzirom na raznovrsnost sastava vitamina E u ulju iz semenki grožđa, potrebna su opsežnija istraživanja koja će obuhvatiti veći broj sorti vinove loze kako bi se izdvojile one sa najvećim potencijalom bio- ulja.VIII Kongres farmaceuta Srbije sa međunarodnim učešćem, 12-15.10.2022. Beogra

Poređenje efikasnosti eutektičke smeše i konvencionalnih rastvarača u ekstrakciji derivata hidroksicimetne kiseline iz herbe Satureja kitaibelii Wierzb. ex Heuff. (Lamiaceae)

Hydroxycinnamic acids (HCAs), such are dimeric rosmarinic acid (RA) and higher HCA oligomers, are important active constituents of Lamiaceae plants. It was found that herb of Satureja kitaibelii (Rtanj tea) contains substantial amounts of RA and HCA hexamer clinopodic acid O (CAO) (1). In this work, we compared extracting efficiencies of conventional solvents and a deep eutectic solvent, composed of choline chloride and citric acid (ChCl:CitrA), for extraction of RA and CAO from Rtanj tea. Commercial Rtanj tea sample was extracted (1:10) by sonication (room temperature, 60 min) with aqueous ChCl:CitrA (35% and 65%), ethanol 50%, ethanol 96%, and water, as well as by previously optimized procedure (ethanol 46%, digestion 60 °C, 120 min) (1). Contents of RA and CAO were determined by HPLC using RA as external standard. Extraction with ChCl:CitrA and 50% ethanol resulted in extracts rich in RA and CAO; RA concentrations in these extracts were uniform (848-873 μg/mL), while extraction of CAO was slightly more effective with ChCl:CitrA (1122-1131 μg/mL) than with 50% ethanol (925 μg/mL). These extracts contained significantly more of RA and CAO than the extract obtained under optimized conditions (666 μg/mL RA, 725 μg/mL CAO). Differently, 96% ethanol and water extracts contained substantially less RA (11-217 μg/mL) and CAO (4-10 μg/mL). Obtained results indicate potential of applied eutectic solvent in extraction of Rtanj tea, for purpose of both quality control and preparation of extracts with potential application in pharmaceutical, food or cosmetic industry, and are compliant with “green chemistry” and “green pharmacy” principles.Derivati hidroksicimetne kiseline (HCK), kao što su dimerna rozmarinska kiselina (RK) i viši oligomeri HCK, su aktivni sastojci biljaka familije Lamiaceae. Ranije je ustanovljeno da herba Satureja kitaibelii (rtanjski čaj) sadrži značajne količine RK i heksamera HCK klinopodinske kiseline O (KKO) (1). U radu je upoređena ekstrakciona efikasnost konvencionalnih rastvarača i duboke eutektičke smeše na bazi holin hlorida i limunske kiseline (ChCl:CitrA) za ekstrakciju RK i KKO iz rtanjskog čaja. Komercijalni uzorak rtanjskog čaja ekstrahovan je (1:10) postupkom sonikacije na sobnoj temperaturi tokom 60 min vodenim rastvorima ChCl:CitrA (35% i 65%), etanolom 50%, etanolom 96% i vodom, kao i prethodno optimizovanim postupkom (etanol 46%, digestija na 60 °C, 120 min) (1). Sadržaj RK i KKO određen je HPLC metodom, korišćenjem RK kao eksternog standarda. Ekstrakcija primenom ChCl:CitrA i 50% etanola rezultirala je ekstraktima bogatim RK i KKO, pri čemu su koncentracije RK u ovim ekstraktima bile ujednačene (848-873 μg/mL), dok je za ekstrakciju KKO, ChCl:CitrA bila nešto efikasnija (1122-1131 μg/mL) od 50% etanola (925 μg/mL). Pored toga, ovi ekstrakti su sadržali veće količine RK i KKO od ekstrakta dobijenog pod ranije optimizovanim uslovima (666 μg/mL RK, 725 μg/mL KKO). Sa druge strane, ekstrakti dobijeni 96% etanolom i vodom sadržali su znatno manje količine RK (11-217 μg/mL) i KKO (4-10 μg/mL). Dobijeni rezultati ukazuju na potencijal primenjene eutektičke smeše u ekstrakciji rtanjskog čaja, kako u cilju kontrole kvaliteta, tako i za pripremu ekstrakata sa primenom u farmaceutskoj, prehrambenoj i kozmetičkoj industriji, što je u skladu sa principima “zelene hemije” i “zelene farmacije”.VIII Kongres farmaceuta Srbije sa međunarodnim učešćem, 12-15.10.2022. Beogra

Comparative analysis of chemical composition and biological activity of fruit extracts obtained from different grape (Vitis vinifera L.) varieties using organic and eutectic solvents

Predmet istraživanja ove doktorske disertacije je ispitivanje bioaktivnih sastojaka (BAS) u ekstraktima plodova 24 sorte vinove loze (Vitis vinifera L.). Istraživanje je sprovedeno kroz četiri faze. Ishod prve faze bio je definisanje optimalnih uslova ultrazvučne ekstrakcije: odnos biljni materijal: rastvarač 1:10, vreme 30 min i temperatura 50 ºC. U drugoj fazi vršena je analiza BAS u hidrofilnim (pokožica i semenke) i lipofilnim ekstraktima (semenke). Sadržaj polifenola je bio najveći u hidrofilnim ekstraktima semenki. Antioksidativna aktivnost ekstrakata bila je u statistički značajnoj korelaciji sa polifenolnim sadržajem (p<0,01). Određen je sastav masnih kiselina (GC-FID) i tokoferola (HPLC-FD) u uljima. U okviru treće i četvrte faze izvršena je detaljna analiza hemijskog sastava (HPLC-MS/MS; UV/DAD) i bioloških aktivnosti etanolnih i eutektičkih ekstrakata (holin hlorid:limunska kiselina, ChCit) pokožice i semenki u najpotentnijim sortama grožđa sa posebnim osvrtom na razlike u efikasnosti rastvarača. Antioksidativna aktivnost je procenjivana pomoću četiri testa (DPPH, FRAP, TEAC i CUPRAC). ChCit je potencirao ekstrakciju antioksidanasa iz pokožice, dok je kod semenki etanol bio neznatno efikasniji. Citotoksična aktivnost je ispitivana na tri ćelijske linije (MRC-5, HeLa i LS 174T). ChCit ekstrakti su inhibirali rast ćelija, dok je inhibicija izostala kod etanolnih ekstrakata. Ekstrakti pokožice su ispoljili jaču citotoksičnost od ekstrakata semenki. Antimikrobna aktivnost je procenjivana na tri soja: S.aureus, E.coli i C.albicans. Semenke su značajnije inhibirale rast mikroorganizama od pokožice. Generalno, ChCit ekstrakti pokožice su ispoljili jači antimikrobni efekat od etanolnih ekstrakata, a u slučaju semenki, etanol je bio efikasniji.The object of this doctoral dissertation is determination of bioactive compounds (BC) in fruit extracts from 24 different grape varieties (Vitis vinifera L.). The investigation was conducted through four phases. The outcomes of the first phase are defined optimal conditions of ultrasound extraction: ratio plant material:solvent 1:10, time 30 min and temperature 50 ºC. In the second phase, BC were analyzed in hydrophilic (skins and seeds) and lipophilic (seeds) extracts. The highest total phenolic content was determined in hydrophilic seed extracts. Antioxidant activity was in a strong correlation with phenolic content (p<0,01). Oils were analyzed in the term of fatty acid composition (GC-FID) and tocopherol content (HPLC-FD). The last two phases were the most important: chemical composition and biological activities of organic (acidified ethanol, EtOH) and eutectic (choline chloride:citric acid, ChCit) skin and seed extracts were evaluated. The aim of this part was to compare the extraction efficiency of two solvents. Antioxidant activity of extracts was investigated using four tests (DPPH, FRAP, TEAC and CUPRAC). ChCit potentiated the extraction of antioxidants from skins; for seeds ethanol was more effective. Cytotoxic effects were evaluated against three cell lines (MRC-5, HeLa and LS 174T). ChCit extracts inhibited cells growth, while ethanol had no effect for tested concentrations. Skin extracts exhibited higher cytotoxic potential in comparison with seed ones. Antimicrobial activity was tested against three microorganisms (S.aureus, E.coli and C.albicans). Seed extracts had a stronger inhibitory effect on microorganisms’ development compared with skin extracts. Regarding differences between solvents, ChCit skin extracts showed higher antimicrobial activity than ethanol skin extracts, but in the case of seeds, ethanol was more efficient

Comparative analysis of chemical composition and biological activity of fruit extracts obtained from different grape (Vitis vinifera L.) varieties using organic and eutectic solvents

Predmet istraživanja ove doktorske disertacije je ispitivanje bioaktivnih sastojaka (BAS) u ekstraktima plodova 24 sorte vinove loze (Vitis vinifera L.). Istraživanje je sprovedeno kroz četiri faze. Ishod prve faze bio je definisanje optimalnih uslova ultrazvučne ekstrakcije: odnos biljni materijal: rastvarač 1:10, vreme 30 min i temperatura 50 ºC. U drugoj fazi vršena je analiza BAS u hidrofilnim (pokožica i semenke) i lipofilnim ekstraktima (semenke). Sadržaj polifenola je bio najveći u hidrofilnim ekstraktima semenki. Antioksidativna aktivnost ekstrakata bila je u statistički značajnoj korelaciji sa polifenolnim sadržajem (p<0,01). Određen je sastav masnih kiselina (GC-FID) i tokoferola (HPLC-FD) u uljima. U okviru treće i četvrte faze izvršena je detaljna analiza hemijskog sastava (HPLC-MS/MS; UV/DAD) i bioloških aktivnosti etanolnih i eutektičkih ekstrakata (holin hlorid:limunska kiselina, ChCit) pokožice i semenki u najpotentnijim sortama grožđa sa posebnim osvrtom na razlike u efikasnosti rastvarača. Antioksidativna aktivnost je procenjivana pomoću četiri testa (DPPH, FRAP, TEAC i CUPRAC). ChCit je potencirao ekstrakciju antioksidanasa iz pokožice, dok je kod semenki etanol bio neznatno efikasniji. Citotoksična aktivnost je ispitivana na tri ćelijske linije (MRC-5, HeLa i LS 174T). ChCit ekstrakti su inhibirali rast ćelija, dok je inhibicija izostala kod etanolnih ekstrakata. Ekstrakti pokožice su ispoljili jaču citotoksičnost od ekstrakata semenki. Antimikrobna aktivnost je procenjivana na tri soja: S.aureus, E.coli i C.albicans. Semenke su značajnije inhibirale rast mikroorganizama od pokožice. Generalno, ChCit ekstrakti pokožice su ispoljili jači antimikrobni efekat od etanolnih ekstrakata, a u slučaju semenki, etanol je bio efikasniji.The object of this doctoral dissertation is determination of bioactive compounds (BC) in fruit extracts from 24 different grape varieties (Vitis vinifera L.). The investigation was conducted through four phases. The outcomes of the first phase are defined optimal conditions of ultrasound extraction: ratio plant material:solvent 1:10, time 30 min and temperature 50 ºC. In the second phase, BC were analyzed in hydrophilic (skins and seeds) and lipophilic (seeds) extracts. The highest total phenolic content was determined in hydrophilic seed extracts. Antioxidant activity was in a strong correlation with phenolic content (p<0,01). Oils were analyzed in the term of fatty acid composition (GC-FID) and tocopherol content (HPLC-FD). The last two phases were the most important: chemical composition and biological activities of organic (acidified ethanol, EtOH) and eutectic (choline chloride:citric acid, ChCit) skin and seed extracts were evaluated. The aim of this part was to compare the extraction efficiency of two solvents. Antioxidant activity of extracts was investigated using four tests (DPPH, FRAP, TEAC and CUPRAC). ChCit potentiated the extraction of antioxidants from skins; for seeds ethanol was more effective. Cytotoxic effects were evaluated against three cell lines (MRC-5, HeLa and LS 174T). ChCit extracts inhibited cells growth, while ethanol had no effect for tested concentrations. Skin extracts exhibited higher cytotoxic potential in comparison with seed ones. Antimicrobial activity was tested against three microorganisms (S.aureus, E.coli and C.albicans). Seed extracts had a stronger inhibitory effect on microorganisms’ development compared with skin extracts. Regarding differences between solvents, ChCit skin extracts showed higher antimicrobial activity than ethanol skin extracts, but in the case of seeds, ethanol was more efficient