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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

Sensory and instrumental astringency determination in wine

Kallithraka, Stamatina January 1997 (has links)
No description available.
2

Vliv kuchyňských úprav na obsah fenolických látek v petrželi zahradní (Petroselinum crispum) / Influence of kitchen treatments on the content of phenolic substances in parsley (Petroselinum crispum)

RAJDLÍKOVÁ, Sylva January 2019 (has links)
The Master's thesis deals with the determination of the total content of phenolic compounds contained in garden parsley (Petroselinum crispum). Specifically, the influence of selected kitchen treatments (drying, boiling) on the content of phenolic compounds of garden parsley was monitored in the following three varieties: Atika, Hanácká, Olomoucká. First, the total polyphenol content was determined by spectrophotometry using Folin-Ciocalteau reagent in fresh parsley extract, further samples were dried and boiled. It was always done separately for root and stem. Thereafter, specific representatives of the phenolic compounds were identified using high performance liquid chromatography from the lyophilized material. The highest concentration of phenolic compounds was found in the dried parsley stem in case of all varieties. The highest content of specific phenolic compounds - apigenin, kaempferol, luteolin was found in the Atika variety, and also in the stems of all the mentioned varieties.
3

Study of therapeutic potential of acid caffeic protocols and diabetes in mice dyslipidemia / Estudo do potencial terapÃutico do Ãcido cafÃico em protocolos de diabetes e dislipidemia em camundongos

Vivianne Machado de AraÃjo 30 April 2014 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / The diabetes and dyslipidemia are important in cardiovascular risk factors. When associated with oxidative stress may accelerate coronary artery disease and progression of atherosclerotic lesions. There are several natural products that stand out as potential therapeutic agents for treatment of such diseases, including caffeic acid, a phenolic compound that has a variety of biological and pharmacological activities described in the literature. Thus, the aim of this study was to evaluate the therapeutic potential of caffeic acid in experimental protocols of diabetes and dyslipidemia, as well as examine their modulating activity under oxidative stress. Hyperlipidemia was induced in male mice using two protocols by means of a single intraperitoneal administration of 400mg/kg Triton WR-1339 and 400mg/kg Poloxamer-407 in all animals, except for the normal control. The treated groups received doses caffeic acid 25 (CA25), 50 (CA50) and 100 mg/kg (CA100). The serum of these animals was analyzed on two different time intervals for total cholesterol, triglycerides and glucose. Liver tissue was analyzed after both protocols dyslipidemia for products of lipid peroxidation, the non-protein sulfhydryl groups (NP-SH) and the antioxidant enzyme superoxide dismutase (SOD). The hypoglycemic activity of caffeic acid was checked by the protocol of diabetes induced by alloxan. Treatment with three doses of caffeic acid and 200mg/Kg fenofibrate significantly reduced total cholesterol and triglyceride levels 24 and 48 hours after induction of dyslipidemia in both protocols dslipidemia. There was also reduced blood glucose at all doses used to induce dyslipidemia with Poloxamer -407. Furthermore, the treatment caused a reduction in the CA and an increase in lipid peroxidation levels of NP -SH in two models of dyslipidemia and in addition, increased levels of SOD-induced hyperlipidemia in Poloxamer-407. Regarding the induction protocol with alloxan diabetes, there was reduction in blood glucose and total cholesterol levels in the three groups treated with caffeic acid. Triglyceride levels were significantly reduced in animals in groups CA25 and CA100. The results suggest that caffeic acid has a beneficial effect in the treatment of dyslipidemia and diabetes, as well as an important antioxidant activity without the presence of adverse effects. However, most studies of chronic so they can ensure the safety and efficacy of its use are needed. / O diabetes e as dislipidemias constituem-se em importantes fatores de risco cardiovascular. Quando associados ao estresse oxidativo podem acelerar a doenÃa arterial coronariana e a progressÃo das lesÃes aterosclerÃticas. Existem vÃrios produtos de origem natural que despontam como potenciais agentes terapÃuticos para tratamentos de tais doenÃas, dentre eles o Ãcido cafeico, um composto fenÃlico que apresenta uma variedade de atividades biolÃgicas e farmacolÃgicas descritas na literatura. Desse modo, o objetivo do presente trabalho foi avaliar o potencial terapÃutico do Ãcido cafeico em protocolos experimentais de diabetes e dislipidemia, bem como analisar sua atividade moduladora sob o estresse oxidativo. A hiperlipidemia foi induzida em camundongos machos atravÃs de dois protocolos, sendo mediante uma Ãnica administraÃÃo intraperitoneal de 400mg/Kg de Triton WR-1339 e 400mg/Kg de Poloxamer-407 em todos os animais, exceto no controle normal.Os grupos tratados com Ãcido cafeico receberam as doses de 25 (AC25), 50 (AC50) e 100 mg/Kg (AC100). O soro desses animais foi analisado em dois intervalos de tempos diferentes para colesterol total, triglicerÃdeos e glicose. JÃ o tecido hepÃtico foi analisado apÃs ambos os protocolos de dislipidemia para os produtos de peroxidaÃÃo lipÃdica, os grupos sulfidrÃlicos nÃo-proteÃcos (NP-SH) e a enzima antioxidante superÃxido dismutase (SOD). A atividade hipoglicÃmica do Ãcido cafeico foi verificada atravÃs do protocolo de diabetes induzida por aloxano. O tratamento com as trÃs doses de Ãcido cafeico e fenofibrato 200mg/Kg reduziram significativamente os nÃveis de colesterol total e triglicerÃdeos 24 e 48 horas apÃs a induÃÃo da dislipidemia em ambos os protocolos de dslipidemia. Houve tambÃm reduÃÃo da glicose sanguÃnea em todas as doses utilizadas ao se induzir a dislipidemia com o Poloxamer-407. AlÃm disso, o tratamento com AC promoveu diminuiÃÃo da peroxidaÃÃo lipÃdica e aumento nos nÃveis de NP-SH nos dois modelos de dislipidemia e, adicionalmente, aumento nos nÃveis de SOD na hiperlipidemia induzida por Poloxamer-407. Em relaÃÃo ao protocolo de induÃÃo de diabetes com aloxano, verificou-se reduÃÃo da glicemia e do colesterol total nos trÃs grupos tratados com Ãcido cafeico. JÃ os nÃveis de triglicerÃdeos foram reduzidos significativamente nos animais dos grupos AC25 e AC100. Os resultados obtidos sugerem que o Ãcido cafeico possui um efeito benÃfico no tratamento das dislipidemias e do diabetes, alÃm de uma importante atividade antioxidante, sem a presenÃa de efeitos adversos durante o estudo. No entanto, sÃo necessÃrios mais estudos de forma crÃnica que possam garantir a seguranÃa e eficÃcia de sua utilizaÃÃo.
4

Functionalised poly(organosiloxane)s as supported liquid membranes

Maxwell, Michael January 1999 (has links)
No description available.
5

Processing of polyphenol-rich sorghums for food

Beta, Trust 03 August 2007 (has links)
Please read the abstract in the section 00front of this document Copyright 1997, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Beta, T 1997, Processing of polyphenol-rich sorghums for food, PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-08032007-125938 / > / Thesis (PhD (Food Science))--University of Pretoria, 2007. / Food Science / unrestricted
6

Improvement of the Physicochemical Attributes and Antioxidants Profiles from Pulse Seeds through Germination

Xu, Minwei January 2019 (has links)
Edible pulse seeds are good sources of food ingredients. Germination has been regarded as an effective process to further improve nutrient digestibility and accessibility of pulse seeds. Our aim was to observe the effect of germination on proximate composition, physicochemical attributes, and phenolic profiles of chickpea (Cicer arietinum L.), lentil (Lens culinaris Merr.), and yellow pea (Pisum sativum L.). In addition, mechanisms of how germination affects the antioxidant activity of phenolic compounds were proposed. Chemical composition, thermal, pasting, and moisture adsorption properties of pulse flours were investigated over 6 days of germination. Protein contents increased by 3 percent points for all pulses over germination. However, lentil had the highest protein content. Lipid contents decreased over germination with chickpea having the greatest decline, from 8.00 to 5.90 g/100g (d.b.). Total starch decreased in lentil and yellow pea during germination. Thermal properties of pulse flours changed slightly, while pasting properties varied among pulses. The highest final viscosities for chickpea, lentil, and yellow pea flours were 1061, 981, and 1052 cP and were observed after 2, 1, and 0 days of germination, respectively. Moisture adsorption isotherms showed improved water adsorption capabilities after germination. Soluble free (SFPs) and polar soluble bound phenolic compounds (PSBPs) were extracted from germinated pulse seeds. Their antioxidant activities were evaluated using both the in vitro system and stripped soybean oil (SSO)-in-water emulsions. Liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry and size-exclusion chromatography with multiangle-light-scattering and refractive-index detection were employed to analyze the phenolic composition and molar mass, respectively. Antioxidant activities of SFPs increased in both in vitro and SSO-in-water emulsion system, however, much lower than those of PSBPs based on SSO-in-water emulsion system. The effect of germination on PSBPs in SSO-in-water emulsion varied between pulses. By virtue of chemometric analysis, nine phenolic compounds were speculated as the pivotal phenolic compounds responsible for the antioxidant activity of PSBPs. In particular, the molar masses of PSBPs had a positive relationship with their antioxidant activity. Protective and co-antioxidative principles were proposed as reasons for the variability of antioxidant activities of PSBPs in oil-in-water emulsions with germination. / Hatch project number ND01593
7

Application of comprehensive 2-dimensional liquid chromatography for the analysis of complex phenolic fractions

Kalili, Kathithileni Martha 12 1900 (has links)
Thesis (MSc (Chemistry and Polymer Science))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: The separation of apple, cocoa and green tea phenolic compounds by comprehensive 2-dimensional liquid chromatography (2-D-LC) has been studied. In the first dimension, phenolic compounds were separated according to polarity by hydrophilic interaction chromatography (HILIC) on a diol stationary phase with a mobile phase containing acetonitrile, methanol, acetic acid and water. Gradient reversed-phase (RP) LC using a C18 column with fluorescence detection was employed in the second dimension to separate compounds according to hydrophobicity. Compounds were identified using negative electrospray ionisation mass spectrometry (ESI-MS) coupled to both HILIC and RP separations. The coupling of HILIC and RP separations proved to be especially beneficial since this provided simultaneous information on both the polarity and hydrophobicity of phenolics. The low degree of correlation (r2 < 0.21) between the two LC modes afforded peak capacities in excess of 3000 for the off-line method. An on-line method was also developed utilizing a short, small particle-packed column to provide fast separation in the second dimension. A 1 mm i.d. column was used in the first dimension for the on-line system to reduce injection volumes onto the second dimension column. A significantly lower practical peak capacity was measured for the on-line system, due largely to the reduction in second dimension peak capacity. On the other hand, analysis could be performed in an automated fashion using the online system reducing the risk of sample alteration and guaranteeing better operation reliability and reproducibility. Especially the off-line comprehensive HILIC × RP-LC method developed demonstrated its utility in the analysis of various groups of phenolic compounds including proanthocyanidins, phenolic acids, flavonols and flavonol conjugates in a variety of natural products. / AFRIKAANSE OPSOMMING: Die skeiding van fenoliese komponente in appel, kakao en groen tee is deur middel van ‘comprehensive’ 2-dimensionele vloeistof chromatografie (2-D-LC) bestudeer. Hidrofiliese interaksie chromatografie (HILIC) is gebruik om die fenoliese komponente in die eerste dimensie te skei op grond van polariteit, deur gebruik te maak van ‘n diol stationêre fase en mobiele fase bestaande uit asetonitriel, metanol, asynsuur en water. ‘n Gradiënt omgekeerde fase (RP) LC analisie op ‘n C18 kolom met fluorosensie deteksie is in die tweede dimensie gebruik om fenole volgens hidrofobisiteit te skei. Negatiewe elektrosproei-ionisasie massa spektometrie (ESIMS) gekoppel aan HILIC en RP skeidings is gebruik vir identifikasie van fenole. Die koppeling van HILIC en RP skeidings veral voordelig deurdat dit gelyktydige informasie verskaf het oor die polariteit sowel as die hidrofobisiteit van die fenoliese komponente. Die lae graad van korrelasie (r2 < 0.21) tussen die twee LC metodes was verantwoordelik vir piek kapasiteite bo 3000 vir die af-lyn metode. ‘n Aanlyn metode was ontwikkel deur gebruik te maak van ‘n kort, klein partikel gepakte kolom om vinnige skeiding in die tweede dimensie te verseker. 1 mm i.d. kolom was gebruik in die eerste dimensie vir die aanlyn sisteem om die inspuit volume op die tweede dimensie kolom te verminder. Aansienlike laer praktiese piek kapasiteit was gemeet vir die aanlyn sisteem, grootliks toegeskryf aan die reduksie in die tweede dimensie piek kapasitiet. Aan die ander kant, analise kan geoutomatiseerd uitgevoer word deur gebruik te maak van die aanlyn sisteem, wat monster alterasie, beter betroubaarheid en reproduseerbaarhied verseker. Veral die ontwikkelde af-lyn ‘comprehensive’ HILIC × RP-LC metode toon demonstreerbare voordele vir die analiese van verskeie groepe fenoliese komponente, insluitende proantosianiede, fenoliese sure, flavonole en gekonjugeerde flavonole in ‘n verskeidenheid natuurlike produkte.
8

Comprehensive two-dimensional liquid chromatographic analysis of phenolics

Kalili, Kathithileni Martha 12 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Phenolic chemistry is quite complex; natural phenolic compounds vary widely in terms of size and chemical properties. The high structural diversity within this family presents severe analytical challenges. High performance liquid chromatography (HPLC) is the preferred method for phenolic analysis; however, conventional HPLC methods offer limited separation power and often provide incomplete separation of the large number of components present in natural phenolic extracts. Multi-dimensional chromatographic techniques have proven much more effective in the analysis of complex samples. The current study explored the potential of comprehensive two-dimensional liquid chromatography (LC×LC) for the characterisation of phenolic compounds in complex natural products, with the emphasis on proanthocyanidins (PACs). Initial work focused on the evaluation of the state of the art in phenolic analysis, to allow information which was used in the development of optimal 1-D separations for use in LC×LC. The combination of hydrophilic interaction chromatography (HILIC) in the first dimension with reversedphase liquid chromatography (RP-LC) in the second dimension afforded an orthogonal and powerful separation system for phenolics, providing separation on the basis of hydrophilicity and hydrophobicity, respectively. A detailed and systematic procedure was therefore developed to allow the optimisation and evaluation of on-line, off-line and stop-flow HILIC×RP-LC methods. Results showed that all three approaches provide much better separation performance than conventional one-dimensional LC (1-D LC) techniques. On-line HILIC×RP-LC offers automation, shorter analysis times, better reproducibility and minimal sample exposure. The off-line and stopflow methods are characterised by much higher peak capacities, but relatively long analysis times. It was also demonstrated that stop-flow operation results in negligible additional band broadening for procyanidins (PCs), implying that this method is an attractive alternative to the off-line method as it offers automation and minimal sample handling. Experimental verification of the predictions based on fundamental principles confirmed the validity of the optimisation procedure for cocoa PCs. The hyphenation of on-line HILIC×RP-LC separation with fluorescence (FL) and mass spectrometry (MS) detection methods provided enhanced resolution in a practical analysis time with the added benefit of selective detection and greater certainty in compound identification. This strategy proved much more powerful, as demonstrated by the identification of the highly complex PACs in grape seeds based on chromatographic retention data in two dimensions and accurate mass information. It was further shown that on-line coupling of HILIC×RP-LC separation with an optimised radical scavenging assay provides an improved approach for screening of individual radical scavengers in complex phenolic fractions, as demonstrated for cocoa, grape seed and green tea extracts. / AFRIKAANSE OPSOMMING: Fenoliese chemie is baie kompleks; natuurlike fenoliese verbindings varieer in terme van beide grootte en chemiese eienskappe. Hierdie hoë strukturele diversiteit binne die familie bied daadwerklike analitiese uitdagings. Hoëverrigtingvloeistofchromatografie (HPLC) is die voorkeurmetode vir fenoliese analises, maar konvensionele HPLC metodes bied egter 'n beperkte skeidingsvermoë en verskaf dikwels onvolledige skeiding van die groot aantal komponente teenwoordig in natuurlike fenoliese ekstrakte. Multi-dimensionele chromatografiese tegnieke is bewys om baie meer effektief te wees met betrekking tot die ontleding van komplekse monsters. Hierdie studie ondersoek die potensiaal van omvattende twee-dimensionele vloeistof chromatografie (LC×LC) vir die karakterisering van fenoliese verbindings in komplekse natuurlike produkte, met die fokus op pro-antosianidiëne (PAC’s). Aanvanklike werk het gefokus op die evaluering van moderne tegnieke vir fenoliese analise – inligting wat in die ontwikkeling van optimale 1-D skeidings vir die toepasing in LC×LC gebruik is. Die kombinasie van hidrofiliese interaksie chromatografie (HILIC) in die eerste dimensie met omgekeerde-fase vloeistof chromatografie (RP-LC) in die tweede dimensie verleen 'n ortogonale en kragtige skeidingsisteem vir fenoliese komponente en verskaf skeiding op grond van onderskiedelik hidrofiliteit en hidrofobiteit. ‘n Gedetailleerde en sistematiese prosedure is dus ontwikkel om die optimisering en evaluering van aan-lyn, af-lyn en stop-vloei HILIC×RP-LC metodes uit te voer. Resultate het getoon dat al drie benaderings baie beter skeidingsvermoë bied as konvensionele een-dimensionele LC (1-D LC) tegnieke. Aan-lyn HILIC×RP-LC bied outomatisering, korter ontledingstyd, beter herhaalbaarheid en minimale monster blootstelling. Die af-lyn en stop-vloei metodes word gekenmerk deur 'n veel hoër piekkapasiteit, maar relatief lang ontledingstye. Daar is ook getoon dat die stop-vloei prosedure geringe bykomende bandverbreding vir prosianodiniëne (PC’s) tot gevolg het, wat beteken dat hierdie metode 'n aantreklike alternatief is vir die af-lyn metode aangesien dit outomatisering bied en minimale monster hantering behels. Eksperimentele verifiëring van die voorspellings gebaseer op fundamentele beginsels bevestig die geldigheid van die optimalisering proses vir kakao PCs. Die koppeling van aan-lyn HILIC×RP-LC skeiding met fluoressensie (FL) en massaspektrometrie (MS) deteksie verskaf verbeterde resolusie binne 'n praktiese ontledingstyd saam met die bykomende voordeel van selektiewe opsporing en groter sekerheid betreffende die verbindings se identifikasie. Hierdie strategie was baie meer kragtig, soos gedemonstreer deur die identifisering van die hoogs komplekse PAC’s in druiwepitte gebaseer op chromatografiese behoud van die integriteit van die data in twee dimensies tesame met akkurate massa inligting. Daar is verder getoon dat aanlyn koppeling van HILIC×RP-LC skeiding met 'n geoptimiseerde radikale vangers deteksie-metode 'n beter benadering bied om die gedrag van individuele radikale vangers in komplekse fenoliese fraksies te bestudeer, soos bewys is vir kakao, druiwepitte en groen-tee ekstrakte.
9

Avaliação dos compostos fenólicos e das propriedades antioxidantes da polpa do pequi (Caryocar spp) processado e in natura / Evaluation of phenolic compounds and antioxidant properties of pulp pequi (Caryocar spp) processed and fresh

Oliveira, Lucillia Rabelo de 14 July 2010 (has links)
O pequi caracteriza-se por possuir expressiva quantidade de compostos fenólicos, que por apresentarem propriedades antioxidantes estão associados com a prevenção da formação de radicais livres. Além de ser consumido in natura, é também comumente consumido na forma processada. No entanto, sabe-se que os antioxidantes presentes nos vegetais podem ser afetados pela forma de processamento e provocam alterações dos teores de fenólicos totais (FT) bem como da sua atividade antioxidante. Este trabalho objetivou avaliar o teor de FT e as propriedades antioxidantes da polpa do pequi processado e in natura. Foram obtidos os extratos alcoólicos (EALC) e aquosos (EAQ), a partir de amostras liofilizadas de diversas polpas de pequi processado (em conserva) e também do in natura, bem como as frações de ácidos fenólicos livres (AFL), ésteres solúveis de ácidos fenólicos (AFS) e ésteres insolúveis de ácidos fenólicos (AFI) de pequi processado (CB1). Os EALC e EAQ, além dos líquidos provenientes das conservas (LC), foram avaliados quanto aos teores de FT, onde se verificou que os EAQ do pequi in natura, principalmente, e do processado tiveram um maior conteúdo de FT quando comparados aos EALC. Os LC, por sua vez, apresentaram valores médios ainda maiores que os EAQ. Com relação ao teor de FT das frações, a AFL se destacou diante da AFS e AFI. Os extratos, LC e frações foram avaliados quanto à atividade antioxidante in vitro pelo sistema &#946;-caroteno/ácido linoléico e também pelo ensaio do radical DPPH&#8226; (2,2 difenil-1-picril-hidrazila). No primeiro, verificou-se que os EAQ e LC do pequi apresentaram maior atividade que os EALC. Foi observada ainda atividade elevada em todas as frações analisadas. No segundo ensaio pelo método do radical DPPH&#8226;, pode-se observar que os extratos aquosos do pequi in natura apresentaram maior atividade, enquanto que, no pequi processado, os extratos alcoólicos e os líquidos das conservas tiveram melhores resultados. Verificou-se também que a AFL possui atividade superior às outras frações. De uma maneira geral, os resultados do pequi processado foram inferiores aos do pequi in natura tanto em relação aos teores de FT como na atividade antioxidante. Verificando-se ainda, que isto se deve principalmente à perda dos FT da polpa, indicando que houve lixiviação destes compostos para os LC. / Pequi characterized by having a significant amount of phenolic compounds, that are related with its antioxidant properties that are associated with the prevention of free radicals. Besides being eaten fresh, it is also widely consumed in processed form. However, it is known that the antioxidants present in plants can be affected by processing form and cause changes in the levels of total phenolic content (FT) and the antioxidant activity. The objective of this study was to evaluate the content of phenolic compounds and the antioxidant properties of the pequi pulp processed and fresh. Were obtained the alcoholic (EALC) and aqueous (EAQ) extracts from lyophilized samples of various pulps pequi processed (canned) and also in nature, as well as the fractions of free phenolic acids (AFL), soluble esters of phenolic acids (AFS) and insoluble esters of phenolic acids (AFI) of processed pequi (CB1). The EALC and EAq, besides the liquid from the canned (LC) were evaluated for the levels of FT, where it was found that the EAQ of the pequi in nature, mainly, and of the processed had, in general, a higher content of FT compared to EALC. The LC, in turn have showed that even greater EAQ. Regarding the content of FT of the fractions, the AFL stood in front of the AFS and AFI. The extracts, LC and fractions were also evaluated for their antioxidant activity in vitro by the system &#946;-caroteno/ linoleic acid and by test DPPH&#8226; (2,2-diphenyl-1-picryl hydrazyl). At first, it was found that the LC and EAQ of the pequi showed greater activity than the EALC. Still high activity was observed in all fractions analyzed. In the second test, we can observe that the EAQ of the pequi in nature showed greater activity, whereas in pequi processed, the EALC and LC had better results. It was also noted that the AFL has superior activity to other fractions. In general, the results of pequi processed were lower than in fresh pequi both in relation to content of FT as antioxidant activity. Verifying also, that this is mainly due to the loss of FT of the pulp, indicating that there was leaching of these compounds to the LC.
10

Analysis and entrapment of select antioxidants from chokecherry and Saskatoon berry fruits

Konecsni, Kelly Alyson 03 June 2011
The major objectives of this research were to produce a phenolic rich isolate from two locally grown Saskatchewan fruits, chokecherries and saskatoons, develop an encapsulation system for the phenolic isolate, and test this system for the delivery of the phenolic isolate in an animal (rat) model. Natural phenolic compounds present in plants such as fruits have antioxidant and free radical scavenging activities, which have been proposed to have health benefits. The extraction of these compounds from plants is commonly performed using methanol despite being toxic to both humans and animals. As such, ethanol was investigated for its ability to extract phenolics from plants as a food safe alternative to methanol. Phenolic extraction from chokecherries with ethanol:formic acid:water (EFW) resulted in higher concentrations (9.83 mg gallic acid equivalents (GAE)/g fresh weight) than with methanol:formic acid:water (MFW) (7.97 mg GAE/g fresh weight). Results from saskatoons showed similar phenolic levels of 4.26 and 4.21 mg GAE/g fresh weight with MFW and ethanol (EFW), respectively. These results showed that EFW was a suitable substitute for MFW in phenolic compound isolation from chokecherries and saskatoons, and could be used to produce extracts that were safe for use in foods and feeds. High performance liquid chromatography with photodiode array detection (HPLC-PDA) was used to determine the phenolic compound composition of the raw fruits and their phenolic rich isolates. Chlorogenic acid was identified in both chokecherry and saskatoon samples, and rutin was also shown to be present in saskatoons. These identifications were based on the relative retention time and ultra violet-visual spectra comparisons to standards. Solid phase extraction (SPE) using Amberlite XAD-16 was employed to produce phenolic isolates from chokecherries and saskatoons. HPLC-PDA results determined that there was a ~2.7x and ~1.6x increase in peak area for chokecherries and saskatoons, respectively when SPE was employed. The antioxidant activity of the extracts and isolates was determined using in vitro radical scavenging tests including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2´-azinobis-3-ethylbenzthiazoline-sulphonic acid (ABTS). The EFW chokecherry extract and isolate had the highest overall free radical scavenging activity. Crude fruit extracts exhibited lower free radical scavenging values compared to the isolate samples in both of the assays performed. The fruit phenolic isolates were encapsulated in chitosan (CH) sodium tripolyphosphate (TPP) nanoparticles at a ratio of 4.0:1.0 (CH:TPP). HPLC-PDA was used to determine the entrapment efficiency of phenolic isolates to be 15.9 ± 2.7% and 23.0 ± 7.1% for chokecherries and saskatoons, respectively. Characteristics such as the size, surface potential and phenolic release were determined for the two fruit isolate containing nanoparticles. The size of the nanoparticles were 527.90 ± 74.57 nm and 443.03 ± 15.79 nm for chokecherries and saskatoons, respectively. Both of the nanoparticle systems had positive surface charges at 52.70 ± 2.93 mV and 54.43 ± 1.27 mV for chokecherries and saskatoons, respectively. The release properties of the CH:TPP nanoparticles containing fruit phenolics were examined in enzymatic simulated intestinal fluid and resulted in ~23% and ~28% release of chokecherry and saskatoon phenolics, respectively. Saskatoon phenolic isolates and isolates encapsulated in CH:TPP were gavage fed to rats (six animals in each of the two groups) at a dosage rate of 276.36 ± 9.74 mg/kg body weight. The saskatoon isolate contained 12.44 ± 0.44 mg/kg body weight anthocyanins (~3.30 mg anthocyanin per rat). These animals were sacrificed after 1 h and all stomach tissue samples in each of the treatment groups contained detectable levels of anthocyanins. In the small intestine tissues all six of the saskatoon isolate and three of the encapsulated isolate groups had detectable amounts of anthocyanins, while in the large intestine tissue, only one sample from the isolate group showed detectable amounts of anthocyanins. Although other tissues were tested (brain, heart, kidney and liver), anthocyanins were not detected. Therefore anthocyanins were detected in the gastrointestinal tract of both of the treatment groups. The research performed therefore illustrated that phenolic compounds can be extracted from fruit sources using EFW and can be successfully encapsulated in chitosan tripolyphosphate capsules allowing for targeted delivery in an animal model.

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