Antocijani - hemijska analiza i biološka aktivnost

Anthocyanins are a group of over 500 different compounds that cause red, purple and blue colours of many plants, especially fruits, vegetables and cereals. Anthocyanins structurally belong to flavones. Mainly fruit is considered the main source of anthocyanins, although they are present in vegetables, roots, bulbs, fruit pulps, pulses and cereals. Huge diversity of anthocyanins, which can be found in nature makes them very complex and interesting group. In plants anthocyanins are present in the form of heterosides. Aglycone anthocyanins are known as anthocyanins. In nature there is 6 well known anthocyanins: pelargonidin, cyanidin, peonidin, delphinidin, malvidin and petunidin. Pelargonidin as stable anthocyanins is the most frequent in nature. The glycoside derivatives of the most widespread in nature are 3-monoside, 3.5 and 3.7 biosides. Interest for anthocyanins is growing over the past few years due to their potential applications in the pharmaceutical industry, the food and cosmetic industries. Despite their great potential, their use is still limited because of their relative instability and the low percentage of extracting from the plant material. Anthocyanins are quite reactive and unstable compounds. They transform reversibly with pH changes. pH is defined as the greatest cause of instability of anthocyanins, and has the greatest impact on colour. Anthocyanins are polar molecules and the most efficient solvent for extraction are the mixture of polar solvent such as ethanol, methanol and acetone. Extraction methods for anthocyanins isolation are not selective because solvents extracted anthocyanins with ballast and the great number of substances such as sugars and organic acids. Because of that, it is necessary to implement a new purification techniques, such as solid phase extraction (SPE), liquid-liquid extraction (LLE), countercurrent chromatography (CCC), and high performance liquid chromatography (HPLC). Identification of anthocyanins play a key role in the taxonomy and evaluate the quality of herbal drugs and foods containing anthocyanins. Reversed phase RP- HPLC connected to a photodiode (DAD detector) is the most used method for detection and identification of anthocyanins. Sample preparation for HPLC analysis usually involves acid hydrolysis of anthocyanins to release anthocyanidins. Anthocyanins may be quantified using any purified standard, but most commonly used is standard of cyanidin-3-glucoside, and quantification is carried out at a wavelength of 520 nm. The method of choice for the rapid screening of total anthocyanins in vegetables and fruits is spectrophotometric determination at 528 nm, with a controlled pH. This method works very well, when the assessment is required and not the accuracy of the quantification. Anthocyanins are poorly absorbed and metabolised to the same extent as other flavonoids, which are considered to have low bioavailability. Examination of bioavailability for most of the anthocyanins was carried out on animals. Most studies have shown maximum concentration in blood after 15min-2h. Interest in anthocyanins has especially grown in recent years due to their positive effects on health. Anthocyanins are effective for chronic diseases, especially in cardiovascular diseases. Together with the other nutritional ingredients are important because of their antioxidant ability, suggesting their potential application in the prevention of several diseases which are associated with oxidative stress. Some plants with high content of anthocyanins play a role in the prevention of mutagenesis and carcinogenesis as inhibitors. Extracts obtained from berries have the highest potential for the removal free radicals. Antioxidant activity of them is proportional to the content of anthocyanins.Antocijani su grupa od preko 500 različitih jedinjenja koja uzrokuju crvenu, ljubičastu i plavu boju mnogih biljaka, a posebno voća, povrća i žitarica. Antocijani strukturno pripadaju flavonima. Uglavnom se voće smatra glavnim izvorom antocijana, mada su oni prisutni i u povrću, korenju, lukovicama, pulpama plodova, mahunarkama i žitaricama. Ogromna raznovrsnost antocijana koja može da se nađe u prirodi čini ih veoma složenom i interesantnom grupom. U biljnim vrstama su prisutni u vidu heterozida. Aglikoni antocijana poznati su kao antocijanidini, a u prirodi je do sad poznato 6 antocijanidina: pelargonidin, cijanidin, peonidin, delfinidin, petunidin i malvidin. Pelargonidin kao najstabilniji antocijanidin je i najviše zastupljen u prirodi. U glikozidne derivate najviše rasprostranjene u prirodi spadaju 3-monozidi, 3,5 biozidi i 3,7 diglukozidi. Interesovanje za antocijane je sve veće proteklih par godina, zbog njihove potencijalne primene u farmaceutskoj industriji, industriji hrane i kozmetičkoj industriji. Uprkos tome njihova upotreba je i dalje ograničena zbog njihove relativne nestabilnosti i niskom procentu ekstrahovanja iz biljnog materijala. Antocijani su reaktivna i dosta nestabilna jedinjenja. Reverzibilno trpe strukturne transformacije sa promenom pH što ima najveći uticaj na boju. pH je određen kao uzročnik najveće nestabilnosti antocijana, i od pH u najvećoj meri zavisi njihova pigmentacija. Antocijani su polarni molekuli tako da su se kao najefikasniji rastvarači za ekstrakciju pokazale smeše polarnih rastvarača kao što su etanol, metanol i aceton. Metode ekstrakcije koje se koriste za izolovanje antocijana nisu selektivne jer pored antocijana ekstrahuje se i veliki broj balastnih materija kao što su šećeri i organske kiseline. Neophodno je implementirati nove tehnike prečišćavanja, kao što su ekstrakcije na čvrstoj fazi (SPE), ekstrakcije tečno-tečno (LLE), kao i korišćenje sofisticiranih hromatografskih tehnika kao što su protivstrujna hromatografija (CCC), i visoko efikasna tečna hromatografija (HPLC). Identifikacija antocijana ima ključnu ulogu u taksonomiji, i proceni kvaliteta biljnih droga i hrane koja sadrži antocijane. Reverzno fazna RP-HPLC povezana sa fotodiodom (DAD detektor) je najviše korišćena metoda za identifikaciju i određivanje antocijana. Priprema uzoraka za HPLC analizu uglavnom podrazumeva kiselu hidrolizu antocijana da bi se oslobodili antocijanidini. Antocijani mogu biti kvantifikovani preko bilo kog prečišćenog standarda, ali najčešće se kao standard koristi cijanidin-3-glikozid, a kvantifikacija se vrši na talasnoj dužini od 520 nm. Metoda izbora za brz skrining ukupnih antocijana u povrću i voću je spektrofotometrijsko određivanje na 528 nm, pri kontrolisanoj pH. Ova metoda funkcioniše veoma dobro gde je potrebna procena, a ne preciznost kvantifikacije. Antocijani se slabo resorbuju i ne metabolišu se u istom stepenu kao drugi flavonoidi, zbog čega se smatra da imaju malu bioraspoloživost. Ispitivanje bioraspoloživosti antocijana uglavnom je vršeno je na životinjama. Većina studija je pokazala da dostižu maksimalnu koncentraciju u krvi nakon 15 min - 2h. Zainteresovanost za antocijane je posebno porasla poslednjih godina zbog njihovih pozitivnih efekata na zdravlje. Deluju kod hroničnih bolesti, a u prvom redu kod kardiovaskularnih oboljenja. Oni su zajedno sa ostalim flavonoidima važni nutritivni sastojci zbog svojih antioksidativnih sposobnosti, sto ukazuje na njihovu potencijalnu primenu u prevenciji nekoliko bolesti koje su povezane sa oksidativnim stresom. Neke biljke sa visokim sadržajem antocijana imaju ulogu u prevenciji mutageneze i inhibitori su kancerogeneze. Ekstrakti dobijeni iz bobičastog voća imaju najveći potencijal uklanjanja slobodnih radikala i kod njih je antioksidativna aktivnost proporcionalna sadržaju antocijana

Chemical analysis and antimicrobial activity of methanol extracts of celandine (Chelidonium majus L.) plants growing in nature and cultured in vitro

Projekat ministarstva br. 143026B i 143041

Antiviral activity of medicinal plants extracts against foodborne norovirus

Medicinal plant extracts (MPE) have a broad antimicrobial activity, including antiviral effects. In our study, eleven dry extract of ten different medicinal plant prepared with two solvents (5%, dimethyl sulfoxide (DMSO) and 30% ethanol in 5% DMSO) in different concentrations have been examined for anti-noroviral activity. The reduction of norovirus > 1 log10 genome equivalents (GE) has been obtained with 1 mg/mL of Aronia melanocarpa leaf extract (AMLE), dried wine Prokupac (WPE) and Hypericum perforatum extract (HyPE). Some of MPE i.e. HyPE, Aronia melanocarpa fruit extract (AMFE) and Punica granatum (PPE) showed better activity when dissolved in 30% ethanol with 5% DMSO. All results of anti-noroviral activity of tested MPE which achieve lt 0.5 log10 GE are considered as not effective

Comparative Analysis of Phenolic Compounds in Seven Hypericum Species and Their Antioxidant Properties

A comparative analysis of the phenolic compounds in the 70% EtOH extracts of Hypericum acutum, H. androsaemum, H. barbatum, H hirsutum, H maculatum, and H richeri has been carried out using high-performance liquid chromatography coupled with photodiode array UV detection and high resolution TOF mass spectrometry. Quercetin, astilbin, I3,II8-biapigenin, orientin, 2"-O-acetylorientin, three phenolcarboxylic acids, and eight flavonols 3-O-glycosides were identified in the extracts on the basis of their on-line UV spectra, accurate mass spectral data, and in comparison of retention times with those from the standards. Fingerprint analysis of the extracts revealed significant differences in the qualitative and quantitative chemical composition of the studied species. Antioxidant assays with various reaction mechanisms were used including ferric reducing antioxidant power (FRAP) assay, DPPH, ABTS, superoxide anion radical scavenging capacity and inhibition of liposome peroxidation induced by Fe2+. The most potent were extracts of H acutum and H maculatum indicating this Hypericum species interesting for further research aimed as a potentially new source of biologically active compounds

Microencapsulation of Sideritis raeseri Boiss. & Heldr. subsp. raeseri Extract Using Spray Drying with Maltodextrin and Whey Protein

Multiple medical properties and beneficial influence on health attributed to the aerial parts of Sideritis raeseri Boiss. & Heldr. subsp. raeseri indicated the need for further investigation. S. raeseri extracts were subjected to microencapsulation by the spray drying process in order to disperse and preserve unstable active compounds within a protective matrix. Two inlet air temperatures (120 and 140 ºC) were applied for the encapsulation of S. raeseri extract in a matrix composed of maltodextrin (10, 20, and 40%) or whey protein (40%). The effects of spray drying on physico-chemical properties, contents of total phenols and flavonoids, as well as of individual flavonoid glycosides of the obtained powders were determined. The 40% whey protein treatment increased bulk density (238.46 mg/mL) while it decreased hygroscopicity (14.27%). In addition, the high maltodextrin concentration of the S. raeseri powder resulted in the highest process efficiency (63.46%), the highest water solubility index (86.40%), and the lowest water absorption index (5.71%). Moreover, powders produced without maltodextrin were characterized by greater content of flavonoid glycosides. Overall, the results suggested that S. raeseri powders produced using spray-dried technique under adequate conditions could be considered as a novel functional and pharmaceutical ingredient

Fractionated high-pressure extraction of polyphenols from elderberry by-product

The main focus of this study was to propose new streams to use plant waste, specifically to put on the demonstration of the possibility to implement emerging, green and safe technology into food and pharmaceutical industries in order to enable more economical waste management. For the isolation of valuable compounds from elderberry press cake (by-product left after pressing of juice), solvents and techniques considered as “acceptable” and “generally regarded as safe” in the food and pharmaceutical industries have been applied. Polyphenols rich elderberry press cake extracts were obtained employing a fractioned high-pressure methodology, supercritical fluid (SFE) and enhanced solvent extractions (ESE). SFE-CO2+ESE comprising a first SFECO2 step in order to remove the low polarity CO2-soluble compounds, and a second ESE step in order to extract polar compounds like anthocyanins have been carried out, as well as ESE without any pretreatment. The process kinetics of the extraction and increase of extraction yields (EY) were monitored at time intervals from 10 to 90 min, while EYs of ESE were measured after 30-220 min of extraction. Higher extract yield occurred in extract obtained by SFE-CO2+ESE (28.70%) showing its advantage over ESE. According to the kinetics results for the two-step extraction approach, extraction time of 100 min might be sufficient to achieve the similar final EY obtained after 220 min. HPLC of obtained extracts was utilized for quantification of polyphenolic compounds, showing cyanidin-3-O-sambubioside as a main compound, followed by rutin and cyanidin-3-O-glucoside. This work is the first to produce anthocyanin-rich fractions from black elderberry press cake using such high-performance technique

Rosehip Extract-Loaded Liposomes for Potential Skin Application: Physicochemical Properties of Non- and UV-Irradiated Liposomes

In the present study, rosehip (Rosa canina L.) extract was successfully encapsulated in phospholipid liposomes using a single-step procedure named the proliposome method. Part of the obtained liposomes was subjected to UV irradiation and non-treated (native) and UV-irradiated liposomes were further characterized in terms of encapsulation efficiency, chemical composition (HPLC analysis), antioxidant capacity, particle size, PDI, zeta potential, conductivity, mobility, and antioxidant capacity. Raman spectroscopy as well as DSC analysis were applied to evaluate the influence of UV irradiation on the physicochemical properties of liposomes. The encapsulation efficiency of extract-loaded liposomes was higher than 90%; the average size was 251.5 nm; the zeta potential was -22.4 mV; and the conductivity was found to be 0.007 mS/cm. UV irradiation did not cause a change in the mentioned parameters. In addition, irradiation did not affect the antioxidant potential of the liposome-extract system. Raman spectroscopy indicated that the extract was completely covered by the lipid membrane during liposome entrapment, and the peroxidation process was minimized by the presence of rosehip extract in liposomes. These results may guide the potential application of rosehip extract-loaded liposomes in the food, pharmaceutical, or cosmetic industries, particularly when liposomal sterilization is needed

Application of gum Arabic in the production of spray-dried chokeberry polyphenols, microparticles characterisation and in vitro digestion method

Due to its high content of phenolics, black chokeberry has been proposed as a health-promoting material, especially use of chokeberry extract as a food or pharmaceuticals. Chokeberry extract was spray-dried using gum Arabic as a carrier. The optimal conditions for the efficient microencapsulation of chokeberry extract using spray-drying technique have been investigated. The aim of our study was to obtain microparticles with the best potential to improve functionality and stability of extracted chokeberry polyphenols, and to investigate the possibility of microbeads to protect active compounds during simulated digestion process. Morphological characteristics of microbeads were analyzed using FTIR and SEM techniques. Zeta potential, particle size and moisture content were determined. Released total phenolics and total anthocyanins content as well as concentration of individual anthocyanins were quantified before and after digestion process. Microparticles exhibited high encapsulation efficiency up to 87%, and high content of released polyphenols was achieved. After in vitro simulated digestion phenolic compounds decreased by 11-24%, exhibited higher protective effect of gum Arabic. Our results showed that chokeberry microparticles obtained by spray drying method could be useful supplements or functional food.

Flavonoidi iz nadzemnih delova Onobrychis montana subsp. scardica

Rutin (1, main constituent) and two flavone C-glycosides, vitexin (2) and vitexin 2 ''-O-alpha-rhamnopyranoside (3) were isolated from the aerial parts of Onobrychis montana subsp. scardica. They were identified by (1)H-NMR, (13)C-NMR and UV-Vis spectroscopy (procedure with shift reagents), and high resolution ESI-MS. A relatively high content of 1 (5.27 mg/g of dry plant material), measured by HPLC, indicated O. montana subsp. scardica as a new natural source of this biologically active compound. The isolated flavonoid compounds might be of value as chemotaxonomic markers.Iz nadzemnih delova Onobrychis montana subsp. scardica izolovani su rutin (1, glavni sastojak) i dva flavonoidna S-glikozida, viteksin (2) i njegov 2''-O-α-ramnopiranozid (3). Njihova struktura je određena primenom 1H-NMR, 13C-NMR i UV spektroskopije (procedura sa reagensima UV-pomeranja) i masene spektrometrije visokog razlaganja (HR-ESI-MS). Relativno visok sadržaj rutina (5.27 mg/g suvog materijala) određen pomoću tečne hromatografije (HPLC), ukazuje na O. montana subsp. scardica kao nov prirodni izvor ovog biološki aktivnog jedinjenja. Izolovana jedinjenja mogu biti i od vrednosti kao hemotaksonomski markeri

Ispitivanje stabilnosti biljnih preparata

Nowdays, the use of products based on medicinal herbs (phytopreparates) are in scientific focus, both in prevention or in treatment of various diseases. Herbal products have been recognized as an excellent source of bioactive compounds which have positive effects on human health. Beside teas, as standard herbal products, phytopreparations are much more represented as final pharmaceutical form on the market today. Phytopreparations must satisfy standard quality, which means that they must be physically, chemically and microbiological stable and have a high degree of purity. In order to determine the stability, storage conditions, shelf-life of the products, stability tests are conducted, which involving tests of environmental factors influence: temperature, relative humidity, light. Stability tests are performed at different stages of development and production. In accordance with the EMEA (European Agency for Drugs and Medical Devices) for a variety of herbal preparations different specific stability tests are conducted.Danas, sve je veći akcenat na upotrebi preparata na bazi lekovitog bilja (fitopreparata), kako u prevenciji tako i u lečenju različitih oboljenja. Biljni preparati su prepoznati kao odličan izvor bioaktivnih komponenti, koji imaju pozitivne efekte na zdravlje ljudi. Pored čajeva, kao standardnih biljnih proizvoda, danas su na tržištu mnogo više zastupljeni fitopreparati kao finalne farmaceutske forme. Fitopreparati moraju biti standardnog kvaliteta, što podrazumeva da moraju biti fizički, hemijski i mikrobilološki stabilni, da su standardizovanog sastava i da su visokog stepena čistoće. U cilju utvrđivanja koliko je jedan proizvod stabilan, definisanja uslova čuvanja, određivanja roka trajanja, sprovode se ispitivanja stabilnosti, koja podrazumevaju ispitivanja uticaja faktora okoline: temperature, relativne vlažnosti vazduha, svetlosti na promenu kvaliteta gotovog proizvoda. Ispitivanja stabilnosti se izvode u različitim fazama razvoja i proizvodnje. U skladu sa zahtevima EMEA (Evropska agencija za lekove i medicinska sredstva) za različite biljne preparate postavljaju se različiti specifični testovi stabilnosti