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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Sušenje i ekstrakcija lista sremuša (Allium ursinum L.) u cilju dobijanja funkcionalnih proizvoda sa bioaktivnim potencijalom / Drying and extraction of the wild garlic leaves (Allium ursinum L.) in order to obtain functional products with bioactive potential

Tomšik Alena 15 October 2018 (has links)
<p>Cilj ove doktorske disertacije je bio odrediti niz tehnolo&scaron;kih postupaka koji bi omogućili iskori&scaron;ćenje sremu&scaron;a u prehrambene i farmaceutske svrhe u svežem ili suvom stanju, kao biljne droge za pripremu različitih formi ekstrakata bogatih bioaktivnim jedinjenjima izolovanih iz njega.<br />List sremu&scaron;a bere se u vrlo kratkom vremenskom periodu tokom proleća, a nakon branja njegovi listovi vrlo brzo venu i gube svoja senzorna, nutritivna i funkcionalna svojstva, zbog čega je dostupnost ove biljne sirovine vremenski vrlo ograničena. Zbog toga su ispitani uslovi skladi&scaron;tenja svežeg lista sremu&scaron;a kako bi se sagledala trajnost sremu&scaron;a za konzumiranje u svežem stanju, ali i mogućnost primene skladi&scaron;tenog sremu&scaron;a za ekstrakciju bioaktivnih jedinjenja. Za dobijanje osu&scaron;enog lista sremu&scaron;a ispitan je uticaj različitih tehnika su&scaron;enja (konvektivno i vakuumsko su&scaron;enje) i temperature su&scaron;enja (40, 50, 60 i 70 &deg;C) na sadržaj bioaktivnih komponenti u osu&scaron;enom proizvodu. Primenom odgovarajuće tehnike su&scaron;enja, povećava se stabilnost i dostupnost listova sremu&scaron;a za potrebe prehrambene i farmaceutske industrije. Primenom savremenih ekstrakcionih tehnika kao &scaron;to je ekstrakcije superkritičnim ugljen-dioksidom, ekstrakcije subkritičnom vodom i ultrazvučne ekstrakcije, ispitan je uticaj procesnih parametara različitih ekstrakcionih tehnika, poput ultrazvučne ekstrakcije (temperatura, vreme ekstrakcije, snaga ultrazvuka, uticaj rastvarača) i ekstrakcije subkritičnom vodom (temperatura, vreme ekstrakcije, dodatak modifikatora), superkritične ekstrakcije ugljen-dioksidom (pritisak i temperatura), dok je maceracija kao konvencionalna tehnika ekstrakcije primenjena za poređenje efikasnosti modernih ekstrakcionih postupaka. U dobijenim ekstraktima ispitan je sadržaj polifenolnih komponenti, antioksidantna aktivnost i sadržaj sumpornih jedinjenja u cilju optimizacije ekstrakcionih parametara i radi utvrđivanja uslova ekstrakcije pri kojima se postiže najveći kvalitet ekstrakata u pogledu sadržaja ciljanih bioaktivnih komponenti.&nbsp; Za odabrane ekstrakte ispitan je antimikrobni potencijal na različite Gram pozitivne i Gram negativne bakterijske sojeve. Za dobijanje stabilnijih formi odabranih ekstrakata primenjena je enkpasulacija spray drying i spray congeling tehnikom. Enkapsuliranim ekstraktima su određene fizičko-hemijske osobine (hemijski sastav, sadržaj vlage, higroskopnost, moć rehidratacije, WAI i WSI) i biolo&scaron;ka aktivnost (antimikrobna i antioksidativna aktivnost).</p> / <p>The aim of this doctoral dissertation was to determine various technological procedures that would enable the use of fresh and dryed wild garlic leaves in foods and pharmaceutical industry, as a herbal drug or nutraceuticals.<br />The availability period of fresh wild garlic is very short and only during the spring season. After harvest, the leaves are quite perishable, wither very quickly and lose their sensory, nutritive and functional properties. This makes the availability time of this herbal raw material very limited. Therefore, the conditions for storing the fresh leaves of wild garlic and the influences of storing conditions on composition of bioactive compounds were examined in order to extend their use in fresh state. In order to obtain dry herbal drug for extraction, influence of various drying techniques (convection and vacuum drying) and drying temperatures (40, 50, 60, 70 &deg;C) were examinated. The stability and availability of wild garlic in food and pharmaceutical industries was extended by drying. The influence of process parameters of different modern extraction techniques - ultrasonic extraction (temperature, extraction time, ultrasonic power, solvent effect) and subcritical water extraction , extraction time, modifier addition), supercritical carbon dioxide extraction (pressure and temperature) - was examined, while maceration (as a conventional extraction technique) was used to evaluate the efficiency of modern extraction methods. The obtained extracts were analysed in terms of the polyphenolic content, the antioxidant activity and the content of sulfur compounds in order to optimize the extraction parameters and determine the extraction conditions for achieving the highest quality of extracts in terms of the content of the target bioactive components. Antimicrobial potential for different Gram positive and Gram negative bacterial strains was tested for selected<br />extracts. To obtain more stable forms of selected extracts encapsulation techniques - spray drying and spray congeling - were applied. Encapsulated extracts were evaluated in terms of physico-chemical properties (chemical composition, moisture content, hygroscopicity, rehydration power, WAI and WSI) and biological activity (antimicrobial and antioxidant activity).</p>
2

Pharmaceutical and chemical analysis of the components carrying the antiplatelet activity of extracts from allium ursinum and allium sativum

Sabha, Dina Talat Tawfiq 09 January 2012 (has links) (PDF)
Allium sativum has a long tradition in medicine. While much is known about its potential healthy effects, nearly nothing is known about wild garlic (allium sativum, ramson), which is very common in the area of Leipzig and has been used as a herbal remedy since centuries. The goal of the present study was to assess a potential anti-platelet activity of these two allium species and to try to identify the chemical active principle. For that purpose various extracts (hydrophilic and lipophilic) were prepared from Allium sativum and Allium ursinum, and analysed using thin layer chromatography and HPLC. After identifying an active, i.e. antiaggregatory extract (see below), this was fractionated and the active fraction was further sub-fractionated for subsequent chemical analysis by mass spectroscopy, ESI (Electrospray ionization), and COSY (Correlation effect spectroscopy), and functional testing. Anti-platelet activity was assessed in human platelets (platelet rich plasma) using a classical turbidimetric method. Platelets were stimulated with various agonists (arachidonic acid, ADP, epinephrine, collagen, A23187) with and without the addition of the extracts or the fractions /sub-fractions. Both Allium Ursinum and Allium sativum extracts exert antiaggregatory effects with EC50 values around 0.1 mg/ml. The garlic extracts are acting by inhibition of the ADP pathway comparable as known from the clinically used drug clopidegrol.The pharmacological active antiaggregatory component of the extracts appears to be lipophilic rather than hydrophilic. This is the first report on an antiplatelet activity of Allium Ursinum. One final structure determined by HPLC, MS, ESI and COSY which exerts the antiplatelets inhibitory effect is β-sitosterol-3-O-β-D-glucoside of the fraction 7-14 crystals. It is considered that about three up to five grams of dried leaves might be enough to exert antiaggregatory effects (comment: in pharmacy normally dried plant material is used in therapy). The second compound with antiaggregatory activity was identified as 1-β-D-galactopyranoside-2, 3-bis-linolenic glycerate. The problem of loosing the active volatile oily components by drying the leaves in future studies looking for the clinical use may be solved by looking for a raw or a refined extract which would be the form of a real phytomedical drug; for example capsules about 120 to 200 micrograms of an alcoholic or better an heptane / oily extract gained from wood garlic leaves would be an useful drug formulation to reach respective concentrations in blood. However, we have to admit that since our investigations were in-vitro, the in-vivo situation is somewhat different due to the metabolism, which is nearly unknown. Nevertheless, this study shows for the first time that allium ursinum does exert anti-platelet activity and that both allium species can unfold antiaggregatory effects which are worth to be investigated in subsequent in-vivo studies. β-sitosterol-3-O-β-D-glucoside and 1-β-D-galactopyranoside-2, 3-bis-linolenic glycerate could be identified as active antiaggregatory principals.
3

Pharmaceutical and chemical analysis of the components carrying the antiplatelet activity of extracts from allium ursinum and allium sativum

Sabha, Dina Talat Tawfiq 15 November 2011 (has links)
Allium sativum has a long tradition in medicine. While much is known about its potential healthy effects, nearly nothing is known about wild garlic (allium sativum, ramson), which is very common in the area of Leipzig and has been used as a herbal remedy since centuries. The goal of the present study was to assess a potential anti-platelet activity of these two allium species and to try to identify the chemical active principle. For that purpose various extracts (hydrophilic and lipophilic) were prepared from Allium sativum and Allium ursinum, and analysed using thin layer chromatography and HPLC. After identifying an active, i.e. antiaggregatory extract (see below), this was fractionated and the active fraction was further sub-fractionated for subsequent chemical analysis by mass spectroscopy, ESI (Electrospray ionization), and COSY (Correlation effect spectroscopy), and functional testing. Anti-platelet activity was assessed in human platelets (platelet rich plasma) using a classical turbidimetric method. Platelets were stimulated with various agonists (arachidonic acid, ADP, epinephrine, collagen, A23187) with and without the addition of the extracts or the fractions /sub-fractions. Both Allium Ursinum and Allium sativum extracts exert antiaggregatory effects with EC50 values around 0.1 mg/ml. The garlic extracts are acting by inhibition of the ADP pathway comparable as known from the clinically used drug clopidegrol.The pharmacological active antiaggregatory component of the extracts appears to be lipophilic rather than hydrophilic. This is the first report on an antiplatelet activity of Allium Ursinum. One final structure determined by HPLC, MS, ESI and COSY which exerts the antiplatelets inhibitory effect is β-sitosterol-3-O-β-D-glucoside of the fraction 7-14 crystals. It is considered that about three up to five grams of dried leaves might be enough to exert antiaggregatory effects (comment: in pharmacy normally dried plant material is used in therapy). The second compound with antiaggregatory activity was identified as 1-β-D-galactopyranoside-2, 3-bis-linolenic glycerate. The problem of loosing the active volatile oily components by drying the leaves in future studies looking for the clinical use may be solved by looking for a raw or a refined extract which would be the form of a real phytomedical drug; for example capsules about 120 to 200 micrograms of an alcoholic or better an heptane / oily extract gained from wood garlic leaves would be an useful drug formulation to reach respective concentrations in blood. However, we have to admit that since our investigations were in-vitro, the in-vivo situation is somewhat different due to the metabolism, which is nearly unknown. Nevertheless, this study shows for the first time that allium ursinum does exert anti-platelet activity and that both allium species can unfold antiaggregatory effects which are worth to be investigated in subsequent in-vivo studies. β-sitosterol-3-O-β-D-glucoside and 1-β-D-galactopyranoside-2, 3-bis-linolenic glycerate could be identified as active antiaggregatory principals.
4

Retųjų augalų buveinių analizė Lyduvėnų kraštovaizdžio draustinyje / Analysis of rare plant habitats in Lyduvėnai landscape reserve

Jasinskas, Sigitas 17 July 2014 (has links)
Visa gyvybė priklauso nuo augalų gebėjimo sugerti saulės šviesos energiją ir paversti ją cheminių medžiagų energija, kurią naudodamas augalas palaiko savo gyvybinius procesus, auga ir dauginasi. Augaline medžiaga maitinasi žolėdžiai gyvūnai, sudarantys bet kurios mitybos grandinės pagrindą, vadinasi, augalų gebėjimas panaudoti saulės energiją palaiko beveik visą gyvybę žemėje. Augalai yra svarbiausi palaikant žemės atmosferos kokybę (Marinelli ir kt., 2006). Darbo tikslas – nustatyti trilapės blignos (Isopyrum thalictroides), daugiametės blizgės (Lunaria rediviva L.), meškinio česnako (Allium ursinum) paplitimą Lyduvėnų kraštovaizdžio draustinyje ir įvertinti retųjų augalų buveinių valdymo principus. Darbo metodai – lauko darbų metu registruoti retieji augalai, augantys Lyduvėnų kraštovaizdžio draustinyje. Maršrutiniu metodu buvo vizualiai stebėti retieji augalai, augantys draustinyje. Augalų būklė įvertinta pagal augalų populiacijos skaičių, gyvybingumą, fiziologinę būseną ir augimo sąlygas. 2014 m. augalų kiekio pokyčiai nustatyti pagal Braun-blanqe metodiką. Gauti duomenys išanalizuoti ir palyginti su ankstesnių tyrimų duomenimis. Darbo rezultatai. Tyrimų metu nustatyta, jog 2014 m. trilapės blignos (Isopyrum thalictroides) ir meškinio česnako (Allium ursinum) gausumas lyginant su ankstesnių metų duomenimis yra padidėjęs. Daugiametės blizgės (Lunaria rediviva L.) augalų... [toliau žr. visą tekstą] / The whole life depends on the plants ability to imbibe the heat of the sun’s rays and transform into energy of chemical substance. The plants use this energy for maintenance of there one vital development, for growth and for propagation. The herbivores feed on plants, they are the basis of any food web. It means, that the plants ability to imbibe the heat of the sun’s rays keep holding almost the whole life on the earth. The producers (plants) are the most important species, which maintains the quality of earth atmosphere. (Marinelli and oth., 2006). Work goal is to ascertain the spreading Isopyrum thalictroides, Lunaria redivida and allium ursinum on the area of Lyduvenai reservation and to appraise the handling principle of thinly growing plants. Work methods. During the work on fields the registration of thinly growing plants on the Lyduvenai reservation. Visual observation was used on shuttle method. The plants status was appraised at number of plants population, vitality, physical state and the growing conditions. Change of plants state was established according to the population, tendency to increase and decrease in population. The obtained data was analyzed and compared with the data of previous research. Work results. During the research was ascertained the condition of all three investigative plants Isopyrum thalictroides, Lunaria redivida and allium ursinum. The condition in comparison with previous research has not... [to full text]

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