Log in

Relevant bibliographies by topics / Synthesis and antioxidant activity / Dissertations / Theses

To see the other types of publications on this topic, follow the link: Synthesis and antioxidant activity.

Dissertations / Theses on the topic 'Synthesis and antioxidant activity'

Author: Grafiati

Published: 4 June 2025

Last updated: 1 August 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Synthesis and antioxidant activity.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

Tegazzini, Diana. "Design, synthesis and activity evaluation of antioxidant peptides." Thesis, Queen's University Belfast, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603073.

Full text

Abstract:

Reactive Oxygen Species (ROS) produced during normal aerobic metabolism, if not promptly removed by the detoxification mechanisms of the cells, can easily react with cell components, especially lipids, producing secondary cytotoxic molecules called reactive carbonyl species (RCSs). RCSs exhibit significant chemical reactivity and can cause protein modification and dysfunction. One of the most important ReSs is 4-hydroxinonenal (HNE), an unsaturated aldehyde that has been strongly linked to Alzheimer'S disease (AD). A new series of dipeptide histidyl hydrazide analogues of carnosine was prepare

APA, Harvard, Vancouver, ISO, and other styles

2

Matias, Guilhermina do Carmo Andrade Negrinho. "Síntese e avaliação da atividade biológica de bisfosfonatos derivados do indazole." Master's thesis, Universidade de Évora, 2012. http://hdl.handle.net/10174/15991.

Full text

Abstract:

Os bisfosfonatos são uma classe importante de fármacos com largo espetro de aplicações no tratamento de doenças do metabolismo mineral do osso. Recentemente, tem sido estudada as suas atividades antitumoral e contra diversos microrganismos. Neste trabalho, efetuou-se a síntese de bisfosfonatos derivados do indazole. Os bisfosfonatos utilizados neste trabalho foram sujeitos a estudos de avaliação de atividade antioxidante, toxicidade e atividade biológica. A atividade antioxidante foi determinada por dois métodos: o método do DPPH (1,1-difenil-2-picril-hidrazil) e o método do β-caroteno/ácido l

APA, Harvard, Vancouver, ISO, and other styles

3

Santos, Nádia Alexandra Esteves. "Synthesis and evaluation of new pyrazoles, glycosylpyrazoles and rutheniumpyrazoles for antioxidant and antitumoral activity." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22521.

Full text

Abstract:

Mestrado em Biotecnologia - Biotecnologia Molecular<br>O cancro é a segunda maior razão de morte em Portugal, a seguir às doenças cardiovasculares. A quimioterapia continua a ser o tratamento mais utilizado e eficaz, no entanto o intervalo onde a dose é eficiente e ao mesmo tempo segura ainda é muito pequeno, podendo ser tóxico para o organismo do paciente. Dessa forma, a procura de novos agentes antitumorais eficientes e seguros tem sido crucial, tendo os pirazóis e os complexos de ruténio (II) um papel muito importante. Vários compostos contendo o anel de pirazol nas suas estruturas já demon

APA, Harvard, Vancouver, ISO, and other styles

4

Baugaard, Carlo. "The synthesis and electrochemical studies of chalcones and flavanones: an investigation of their antioxidant activity." Thesis, University of Western Cape, 2013. http://hdl.handle.net/11394/3312.

Full text

Abstract:

>Magister Scientiae - MSc<br>Flavonoids, one of the biggest classes of secondary metabolites, are found abundantly in nature in a broad range of fruits, vegetables and beverages such as tea, coffee, beer, wine and fruit drinks. Flavonoids have been reported to exert multiple biological functions as well as tremendous pharmacological activity, including anticancer activity, protection, antioxidant activity, cardiovascular protection, antibacterial, antifungal and antiviral activity. The antioxidant activity of flavones is reported to be associated with those bearing hydroxyl functions. In the

APA, Harvard, Vancouver, ISO, and other styles

5

Al, Bittar Sheiraz. "3-Deoxyanthocyanins : Chemical synthesis, structural transformations, affinity for metal ions and serum albumin, antioxidant activity." Thesis, Avignon, 2016. http://www.theses.fr/2016AVIG0264.

Full text

Abstract:

Ce travail porte sur la synthèse chimique d’analogues simples d’anthocyanes, une classe majeure de pigments naturels solubles dans l’eau. Onze ions flavylium substitués par des groupements hydroxyl,méthoxyl et beta-D-glucopyranosyloxyl en positions 4’, 5 et 7 ont été préparés en utilisant des procédures simples. De plus, les deux principales 3-désoxyanthocyanidines du sorgho rouge, l’apigéninidine (APN) et la lutéolinidine (LTN), ont été synthétisées en une seule étape. Les propriétés physico-chimiques ainsi que l’activité antioxydante ont été étudiées pour le chlorure de 3’,4’,7-trihydroxyfla

APA, Harvard, Vancouver, ISO, and other styles

6

SERRA, ELENA. "Design, Synthesis, Characterization and Investigation of Structure-Activity Relationships on Antioxidants and/or UV Filtering Properties of New Potential Sunscreen Molecules." Doctoral thesis, Università degli studi di Ferrara, 2020. http://hdl.handle.net/11392/2487895.

Full text

Abstract:

Il mio lavoro di dottorato nasce da una collaborazione tra l’Universita’ di Ferrara e il centro ricerche Aptuit, (presso Verona) avendo come tutor rispettivamente il Prof. Stefano Manfredini e il Dr. Daniele Andreotti. I raggi UV (ultravioletto) sono responsabili della maggior parte degli effetti cutanei causati dal sole quali invecchiamento precoce, tumore della pelle, melanoma,etc. Esistone diversi strumenti per proteggersi durante l’esposizione dagli effetti dannosi di tali raggi UVA e UVB, come ad esempio l’utilizzo di cappelli, indumenti di fibre naturali, occhiali da sole, ma anche stru

APA, Harvard, Vancouver, ISO, and other styles

7

Mari, Giacomo. "Synthesis of various and interesting heterocycles included berberino derivatives." Doctoral thesis, Urbino, 2018. http://hdl.handle.net/11576/2656415.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Jinno, Shuji. "Studies on Synthesis and Structure-Activity Relationship of Phenolic Antioxidants of Yeasts." Kyoto University, 1999. http://hdl.handle.net/2433/181405.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Tarushi, Alketa, Chrisoula Kakoulidou, Catherine P. Raptopoulou, et al. "Zinc complexes of diflunisal: Synthesis, characterization, structure, antioxidant activity, and in vitro and in silico study of the interaction with DNA and albumins." ELSEVIER SCIENCE INC, 2017. http://hdl.handle.net/10150/623572.

Full text

Abstract:

From the reaction of ZnCl2 with the non-steroidal anti-inflammatory drug diflunisal (Hdifl), complex [Zn(difl-O)(2)(MeOH)(4)], 1 was formed, while in the presence of a N,N'-donor heterocyclic ligand 2,2'-bipyridylamine (bipyam), 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) and 2,2'-dipyridylketone oxime (Hpko), the complexes [Zn(difl-O,O')(2)(bipyam)], 2, [Zn(difl-O,O')(2)(bipy)], 3, [Zn(difl-O,O')(2)(phen)], 4 and [Zn(difl-O)2(Hpko)(2)], 5 were isolated, respectively. The complexes were characterized by physicochemical and spectroscopic techniques and the crystal structures of complexes

APA, Harvard, Vancouver, ISO, and other styles

10

Santos, Bruna Celeida Silva. "Síntese e modelagem molecular de análogos do metil chavicol e seus potenciais farmacológicos." Universidade Federal de Juiz de Fora (UFJF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/6070.

Full text

Abstract:

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-01-10T17:17:06Z No. of bitstreams: 1 brunaceleidasilvasantos.pdf: 5993103 bytes, checksum: 7eedadf4d8bccdd543fe319f2058cbd4 (MD5)<br>Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-01-23T11:54:04Z (GMT) No. of bitstreams: 1 brunaceleidasilvasantos.pdf: 5993103 bytes, checksum: 7eedadf4d8bccdd543fe319f2058cbd4 (MD5)<br>Made available in DSpace on 2018-01-23T11:54:04Z (GMT). No. of bitstreams: 1 brunaceleidasilvasantos.pdf: 5993103 bytes, checksum: 7eedadf4d8bccdd543fe319f2058cbd4 (MD5) Previ

APA, Harvard, Vancouver, ISO, and other styles

11

Brizzolari, A. "BIOLOGICAL ACTIVITY OF SOME NATURAL AND SYNTHETIC N6-SUBSTITUTED ADENOSINE DERIVATIVES (CYTOKININ RIBOSIDES)." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/337370.

Full text

Abstract:

In this Ph.D project, some natural N6 – substituted adenosine derivatives, cytokinin ribosides (CKRs) have been investigated with the aim to draw a profile of their biological activity. CKRs belong to a class of plant hormones playing various roles in many aspects of plant development. We chose the most representative among natural cytokinin ribosides, namely N6 – isopentenyl adenosine (iPAdo), kinetin riboside (KR), N6-benzyl adenosine (BA) and its hydroxylated derivative, ρ- topolin riboside (p-TR). In the first part of the thesis, the platelet anti aggregation activity CKRs has been evalu

APA, Harvard, Vancouver, ISO, and other styles

12

Arts, Mariken J. T. J. "Assessing antioxidant activity." [Maastricht : Maastricht : Universiteit Maastricht] ; University Library, Universiteit Maastricht [host], 2007. http://arno.unimaas.nl/show.cgi?fid=8676.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

O'Reilly, James Daniel. "Antioxidant activity of dietary flavonoids." Thesis, King's College London (University of London), 1999. https://kclpure.kcl.ac.uk/portal/en/theses/antioxidant-activity-of-dietary-flavonoids(10c771a4-169d-405b-a1cd-354e86ebd109).html.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

James, Leanne. "Manganese complexes with biomimetic antioxidant activity." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/7073.

Full text

Abstract:

Several seven-coordinate manganese complexes have been synthesised, characterised and tested for both superoxide dismutase and catalase activity. Macrocyclic ring contractions have led to a series of new seven coordinate mononuclear manganese(II) macrocycles that have potential for their use as working superoxide dismutase mimics. Numerous polynuclear seven coordinate manganese(II) macrocycles have been synthesised via Schiff base condensation. Subsequent reduction of the imine bonds has led to a variety of reduced amine analogues with varying axial ligands. The geometry has been compared abou

APA, Harvard, Vancouver, ISO, and other styles

15

Williamson, E. "The antioxidant activity of #DELTA#'5-avenasterol." Thesis, University of Reading, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233864.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Branco, Diana Patrícia Rodrigues. "Metallothionein functions: metal chelation and antioxidant activity." Master's thesis, Universidade de Aveiro, 2011. http://hdl.handle.net/10773/7317.

Full text

Abstract:

Mestrado em Biologia Aplicada - Biologia Molecular Celular<br>It is generally accepted that the principal roles of metallothioneins (MTs) lie in the detoxification of toxic metals and regulation of the metabolism of essential trace metals. However, there is increasing evidence that it can act as a free radical scavenger. Although the great number of studies on the antioxidant activity of MTs, the effective physiological role of this protein is still unclear. In order to understand the role of MTs in the protection against metal contamination and oxidative stress, the bivalve Cerastoderma edule

APA, Harvard, Vancouver, ISO, and other styles

17

Keceli, Turkan. "Antioxidant and antimicrobial activity of olive oil phenolics." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325073.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Quartley, Benjamin J. P. "The antioxidant activity of green tea in vivo." Thesis, University of Surrey, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308646.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Mohamed, Amal. "Antioxidant activity of flaxseed proteins and their hydrolysates." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119689.

Full text

Abstract:

Certain components of flaxseed are known to exhibit antioxidant activity. The objective of this research was to study the antioxidant activity of flaxseed proteins and protein hydrolysates. Proteins and their hydrolysates were prepared from defatted, non-defatted, and demucilaged flaxseed with and without dialysis, and the antioxidant activities were examined by DPPH scavenging assay, reducing power assay, and metal ion chelating assay. The degree of hydrolysis (DH) of the proteins using bacterial protease was higher than using trypsin. Using bacterial protease, higher DH was observed for demu

APA, Harvard, Vancouver, ISO, and other styles

20

Johnson, Michelle E., W. Andrew Clark, S. E. Dahlman, W. D. Elrod, and C. M. Stanage. "Betalain in Beets Enhance Antioxidant Activity in Hummus." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/2515.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Liu, Zheng-Xian. "Antioxidant activity of Mn-salophen complex and its effects on antioxidant enzymes in Escherichia coli." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/40046.

Full text

Abstract:

Mn-salophen complex with superoxide-scavenging activity was prepared from manganese(III) acetate dihydrate and salophen in ethanol. Visible absorption spectrum of the red-brown solution exhibited a broad absorption band at 430 - 450 nm with two shoulders between 500 and 600 nm which were absent with either salophen or manganic acetate alone. Titration of salophen with manganese(III) was consistent with a 1:1 Mn to salophen stoichiometry of the complex based on changes in the absorbance at 500 nm or of superoxide scavenging activity. The SOD-like activity of the complex in the xanthine-xanthine

APA, Harvard, Vancouver, ISO, and other styles

22

Niero, Giovanni. "Development of analytical methods for phenotypic characterization of antioxidant compounds and antioxidant activity of milk." Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3427152.

Full text

Abstract:

Free radicals are unstable and reactive molecules, with one ore more unpaired electrons in the outer orbit and adverse effects on plant, animal, and human cells. In particular free radicals are responsible of lipids peroxidation, proteins oxidative damages, and DNA cleavage, resulting in increased risk of mutation. Antioxidants represent an important defence against these injuries. Vegetable derived foods are known as important sources of dietary antioxidants such as phenols, anthocyanin, tocopherols, tocotrienols, carotenoids, retinol precursors, and ascorbate. With this background, the aim

APA, Harvard, Vancouver, ISO, and other styles

23

Singh, Prabhjot. "Antioxidant activity of food proteins and food protein hydrolysates." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104895.

Full text

Abstract:

The objective of this research was to study the antioxidant activity of soybean protein hydrolysates (SPH) and chickpea protein hydrolysates (CPH) at different concentrations, and to measure the antioxidant activity of fractions collected from the RP-HPLC analysis of SPH and CPH. Protein hydrolysates were prepared by the proteolytic enzyme trypsin. The hydrolysates obtained were subjected to DPPH (1, 1-diphenyl-2 picrylhydrazyl) radical scavenging assay. The SPH and CPH at concentration of 2.5-10 mg/ml showed antioxidant activity of 16.5-32 % and 3.4-26.8 %. SPH and CPH were fractionated by us

APA, Harvard, Vancouver, ISO, and other styles

24

Juan-Badaturuge, Malindra. "Antioxidant activity and phytochemical evaluations of selected medicinal plants." Thesis, University of Greenwich, 2010. http://gala.gre.ac.uk/8098/.

Full text

Abstract:

The methanolic crude extract of aerial parts of the plant Scrophularia nodosa was shown to have potent DPPH radical scavenging activity (IC50 = 48.75 ± 7.00 μg/ml). Activity-guided fractionation resulted in the isolation of three principal antioxidant compounds; acteoside, angoroside C and angoroside A. Acteoside (yield = 1.21%, IC50 = 15.2 μM) appeared to be the most abundant and most antioxidant-active. The potent antioxidant activity is in support of the traditional use of the plant for wound healing and anti-inflammatory conditions. The methanolic extract of aerial parts of Tanacetum vulga

APA, Harvard, Vancouver, ISO, and other styles

25

Tsang, Catherine. "Antioxidant activity, protective effects and absorption of polyphenolic compounds." Thesis, University of Glasgow, 2004. http://theses.gla.ac.uk/1560/.

Full text

Abstract:

The objectives of the studies presented in this thesis were to identify and quantify the major phenolic components of red wine and to assess the contribution of individual compounds to the total antioxidant activity. Red wines were analysed for their phenolic content and antioxidant activity using a range of complementary techniques including HPLC-tandem mass spectrometry, preparative HPLC and HPLC with an on-line antioxidant detection system. HPLC-MS2 revealed the presence of a number of flavoids and phenolic compounds of which 19 were identified, with gallic acid, the flavin-3-ols and anthoc

APA, Harvard, Vancouver, ISO, and other styles

26

Kasase, Chitundu. "Antihypertensive and antioxidant activity of peptides derived from fish." Thesis, University of Surrey, 2009. http://epubs.surrey.ac.uk/844585/.

Full text

Abstract:

Peptides derived from food proteins after enzymatic treatment and/or processing, are known to be bioactive in both biological and food systems; for this reason fish muscle peptides were investigated for their antihypertensive and antioxidant activity. Atlantic mackerel muscle proteins were hydrolysed with pepsin and pancreatine and the resultant hydrolysate was sequentially fractionated on 2 kDa membrane ultrafilters and further by gel filtration, ion exchange and high performance liquid chromatography and the resultant peptide fraction contained the amino acids histidine, proline, tyrosine, m

APA, Harvard, Vancouver, ISO, and other styles

27

Rosales, Soto Maria U. "Phenolics, anthocyanins and antioxidant activity in red raspberry muffins." Pullman, Wash. : Washington State University, 2008. http://www.dissertations.wsu.edu/Thesis/Fall2008/M_Rosales_082708.pdf.

Full text

Abstract:

Thesis (M.S. in food science)--Washington State University, December 2008.<br>Title from PDF title page (viewed on Dec. 31, 2008). "School of Food Science and Human Nutrition." Includes bibliographical references.

APA, Harvard, Vancouver, ISO, and other styles

28

Wattamwar, Paritosh P. "SYNTHESIS AND CHARACTERIZATION OF POLYMERIC ANTIOXIDANT DELIVERY SYSTEMS." UKnowledge, 2011. http://uknowledge.uky.edu/cme_etds/2.

Full text

Abstract:

Even though the role of oxidative stress in a variety of disease states is known, strategies to alleviate this oxidative stress by antioxidants have not been able to achieve clinical success. Particularly, treatment of oxidative stress by small molecule antioxidants has not received due attention because of the challenges associated with its delivery. Antioxidant polymers, where small molecule antioxidants are incorporated into the polymer backbone, are an emerging class of materials that can address some of these challenges. In this work, biodegradable polymers incorporating phenolic antioxid

APA, Harvard, Vancouver, ISO, and other styles

29

Mothapo, Mmaphefo Patricia. "Comparative evaluation of three fundamentally different analytical methods antioxidant activity determination with reference to bush tea (anthrixia phylicoides." Thesis, University of Limpopo, 2016. http://hdl.handle.net/10386/1517.

Full text

Abstract:

Thesis (M.Sc. (Chemistry)) -- University of Limpopo, 2016<br>In this study, antioxidant activity methodologies were evaluated in terms of analytical performances. The total antioxidant activity from Athrixia phylicoides leaves (Bush tea) determined using 2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH•) method, cupric ion reducing power (CUPRAC) method and cyclic voltammetry (CV). Folin-Ciocalteu method was used to quantify total phenolic content (TPC) in Athrixia phylicoides leaves. The influence of chemical and physical parameters on the total phenolic content and antioxidant activity

APA, Harvard, Vancouver, ISO, and other styles

30

Betancor, Fernández Alejandro José. "Biological properties of micronutrients: antioxidant capacity and structure activity relationships." [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970026293.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

ZHONG-YOU, LAI, and 賴忠佑. "Synthesis and antioxidant activity of Ugonin T derivatives." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/y5krx6.

Full text

Abstract:

碩士<br>中國文化大學<br>化學系應用化學碩士班<br>107<br>Several flavonoids were found from Helminthostachys zeylanica. Ugonin T (1) was isolated and characterized as a minor component from the rhizomes of Helminthostachys zeylanica. Ugonin T possesses a flavone skeleton containing a dihydrofuran ring. Ugonin T was found to show anti-inflammatory activity. Until now, the total synthesis of ugonin T has not been reported yet. In this thesis, an efficient synthetic method for the total synthesis of ugonin T and analogues was established. The key intermediate 1-(6-hydroxy-4-methoxy-2,3,3-trimethyl-2,3-dihydrobenzofu

APA, Harvard, Vancouver, ISO, and other styles

32

MCGRATH, ALAINA J. "Synthesis, Redox Chemistry and Antioxidant Activity of Sulfenic Acids." Thesis, 2010. http://hdl.handle.net/1974/6222.

Full text

Abstract:

Sulfenic acids figure prominently in biological and natural products chemistry as important intermediates. For example, cysteine derived sulfenic acids are key intermediates in cell signaling and play both catalytic and structural roles in enzymes. Due to the ubiquitous nature of protein sulfenic acids in cells, methods have been developed to detect and quantitate them. Although they can be detected, the mechanisms by which they form and react remain unclear. In addition, sulfenic acids are important enzymatic intermediates in Allium chemistry. Garlic, a member of the Allium genus, is known t

APA, Harvard, Vancouver, ISO, and other styles

33

Mao, Qinyong. "The synthesis and antioxidant capacities of a range of resveratrol and related phenolic glucosides." Thesis, 2015. http://hdl.handle.net/2440/97992.

Full text

Abstract:

The resveratrol analogues have attracted great attension by scientists as these compounds exhibit numerous bioactive properties due to their outstanding antioxidant capacity. However, the role of the antioxidant activity of these molecules is still not quite clear. This thesis details the development and biological evaluation of a library of resveratrol analogues in order to provide a better understanding of their pharmaceutical value. This thesis begins with an overview of an important hydroxylated stilbene (resveratrol) and its analogues present in natural plants, food and beverage. Consequ

APA, Harvard, Vancouver, ISO, and other styles

34

Chen, Yan-Ru, and 陳燕茹. "Synthesis and Evaluation of [6]-Paradol and Zingerol Derivatives on Antioxidant Activity." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/k8d528.

Full text

Abstract:

碩士<br>弘光科技大學<br>化妝品科技研究所<br>104<br>In this study, we synthesized five [6]-paradol derivatives from 4-hydroxybenzoic acid, β-resorcylic acid, gentisic acid, 3-methoxysalicylic acid and vanillic acid, respectively. We also prepared three zingerol derivatives from β-resorcylic acid, gentisic acid and vanillic acid, respectively. This study aimed to evaluate their antioxidant activities in different systems including of DPPH, ABTS free radical scavenging, ferric reducing power and FRAP assay in order to determine the different reactivities of [6]-paradol and zingerol derivatives. [6]-Paradol and z

APA, Harvard, Vancouver, ISO, and other styles

35

Lin, Chi-Wei, and 林季緯. "Synthesis and Evaluation of Novel Zingerol Derivatives on Tyrosinase Inhibition and Antioxidant Activity." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/49s4vb.

Full text

Abstract:

碩士<br>弘光科技大學<br>化妝品科技研究所<br>103<br>In this study, we synthesized four zingerol derivatives from hydroxybenzoic acids and evaluated their tyrosinase inhibition and antioxidant activities in order to determine the bioactivity of zingerol and the four derivatives. Zingerol shows no significant inhibitory effect on mushroom tyrosinase in 10 mM concentration. IC50 value of tyrosinase inhibition of β-arbutin used as a control group is 5.48 mM. Zingerol has great antioxidant activities and the IC50 values of ABTS and DPPH are 102.84 and 73.13 μM, respectively. Vitamin C is used as a control group and

APA, Harvard, Vancouver, ISO, and other styles

36

Bhuyan, Bhaskar Jyoti. "Design And Synthesis Of Novel Angiotensin Converting Enzyme (ACE) Inhibitors Having Antioxidant Activity." Thesis, 2010. https://etd.iisc.ac.in/handle/2005/1339.

Full text

Abstract:

Angiotensin converting enzyme (ACE) catalyzes the conversion of angiotensin I (Ang I) to angiotensin II (AngII). ACE also cleaves the terminal dipeptide of vasodilating hormone bradykinin (a nonapeptide) to its inactive form. Therefore, inhibition of ACE is one of the treatments of hypertension. A number of ACE inhibitory antihypertensive drugs are known. ‘Oxidative stress’ is another disease state caused by an imbalance in the production of oxidants and antioxidants in the body. A number of studies suggest that hypertension and oxidative stress are interdependent. Therefore, ACE inhibitors ha

APA, Harvard, Vancouver, ISO, and other styles

37

Bhuyan, Bhaskar Jyoti. "Design And Synthesis Of Novel Angiotensin Converting Enzyme (ACE) Inhibitors Having Antioxidant Activity." Thesis, 2010. http://etd.iisc.ernet.in/handle/2005/1339.

Full text

Abstract:

Angiotensin converting enzyme (ACE) catalyzes the conversion of angiotensin I (Ang I) to angiotensin II (AngII). ACE also cleaves the terminal dipeptide of vasodilating hormone bradykinin (a nonapeptide) to its inactive form. Therefore, inhibition of ACE is one of the treatments of hypertension. A number of ACE inhibitory antihypertensive drugs are known. ‘Oxidative stress’ is another disease state caused by an imbalance in the production of oxidants and antioxidants in the body. A number of studies suggest that hypertension and oxidative stress are interdependent. Therefore, ACE inhibitors ha

APA, Harvard, Vancouver, ISO, and other styles

38

CHAN, YI-HSUAN, and 詹依璇. "Study on Antioxidant Activity of Synthetic Chlorogenic Acid Derivatives." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/p87vj6.

Full text

Abstract:

碩士<br>弘光科技大學<br>化妝品應用研究所<br>107<br>The objectives of the present study were to chlorogenic acid derivatives ((E)-2-amino-3-((3-((3-(3,4-dihydroxyphenyl)acryloyl)oxy)-1,4,5-trihydroxycyclo hexanecarbonyl) thio) propanoic acid, CGAC) were synthesized by the esterification reaction of chlorogenic acid and cysteine. Characterization of CGAC was performed by FTIR, 1H and 13C NMR spectroscopic methods analysis. Antioxidant activity of the CGAC was evaluated using DPPH, ABTS▪+, total phenolic content, β-carotene-linoleic acid assay. The whitening effects of CGAC by the activity of chelating ability C

APA, Harvard, Vancouver, ISO, and other styles

39

Lin, Kun-ying, and 林昆瑩. "Studies on Synthesis of Hydroxy Subsituted of N-Benzoyltyramine Derivatives as Inhibitory Activity of Antioxidant and Tyrosinase." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/28a93n.

Full text

Abstract:

碩士<br>嘉南藥理科技大學<br>化妝品科技研究所<br>97<br>This research utilized the method of organic synthesis to put different amounts and positions of hydroxy-substituted tyramine or hydroxy- substituted dopamine into benzoic acid so as to produce a series of hydroxy-substituted N-benzoyltyramine derivatives (Compounds 1~20). Through the following tests, I. The ability of antioxidant—to scavenge DPPH free radical and ABTS free radical, II. The activity test of inhibit tyrosinase, III. The activity test of absorb UV in UV-Vis spectrometer. Compared with controlled groups, such as trolox, vitamine C, arbutin, a

APA, Harvard, Vancouver, ISO, and other styles

40

Lo, Chen-Wei, and 羅振維. "Studies on Synthesis of Hydroxy Substituted of N-Benzoylserotonin Derivatives as Inhibitory Activity of Antioxidant and Tyrosinase." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/57j96v.

Full text

Abstract:

碩士<br>嘉南藥理科技大學<br>化妝品科技研究所<br>97<br>This research utilized the method of organic synthesis, researching different amounts and positions of hydroxy-substituted benzoic acid and serotonin into amide reaction, so as to produce a series of polyhydroxy substituted N-benzoylserotonin derivatives (compound 1-10). Accordingly, this study conducts the following four tests. I. The activity of antioxidant and the experiment of ability to scavenge DPPH free radical, II. The ability of overall antioxidant—the activity of TEAC, III. The activity test of inhibit Tyrosinase, and IV. The study of absorbing U

APA, Harvard, Vancouver, ISO, and other styles

41

Tseng, Wei-Yi, and 曾維毅. "Studies on Synthesis of Hydroxy Subsituted of N-Cinnamoyltyramine Derivatives as Inhibitory Activity of Antioxidant and Tyrosinase." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/51837851753789707963.

Full text

Abstract:

碩士<br>嘉南藥理科技大學<br>化妝品科技研究所<br>96<br>This research utilized the method of organic synthesis to put different amounts and positions of Hydroxy-substituted Tyramine and Hydroxy-substituted Dopamine into Cinnamic acid or Caffeic acid so as to produce a series of Hydroxy-substituted N-Cinnamoyltyramine Derivatives (Compounds 1~16). Through the following tests, this research studies those compounds’ applied value of cosmetics. I. The activity of antioxidant and the experiment of ability to scavenge DPPH free radical, II. The ability of total antioxidant—the activity of TEAC, III. The activity test

APA, Harvard, Vancouver, ISO, and other styles

42

Zhuang, Ting-xun, and 莊庭珣. "Studies on Synthesis of Hydroxy Substituted of N-Cinnamoylserotonin Compounds as Inhibitory Activity of Antioxidant and Tyrosinase." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/76315860712577844861.

Full text

Abstract:

碩士<br>嘉南藥理科技大學<br>化妝品科技研究所<br>96<br>This research utilized the method of organic synthesis to put Hydroxy Substituted of N-Cinnamoyl Derivatives and Serotonin together, undergoing Benzamides reaction, so as to acquire a series of Hydroxy-substituted of N-Cinnamoylserotonin compounds (compound 1~8). Accordingly, this research would discuss the compounds’ ability of antioxidant, their ability of inhibiting tyrosinase, and their ability of absorbing UV, compared with controlled groups, such as Vitamin C, Vitamin E, kojic acid, and PMCX. Through the following tests, this research studies those c

APA, Harvard, Vancouver, ISO, and other styles

43

Bhabak, Krishna Pada. "Synthetic Antioxidants : Structure-Activity Correlation Studies Of Glutathione Peroxidase Mimics And Peroxynitrite Scavengers." Thesis, 2009. https://etd.iisc.ac.in/handle/2005/996.

Full text

Abstract:

Reactive oxygen species (ROS) such as superoxide radical anion (O2•¯), hydroxylradical (OH•), hydrogen peroxide (H2O2) and peroxynitrite (ONOO-) that are produced during the metabolism of oxygen under oxidative stress in aerobic organisms destroy several key biomolecules and lead to a number of disease states. Mammalian systems possess several effective defense mechanisms including antioxidant enzymes to detoxify these ROS. The selenocysteine-containing Glutathione peroxidase (GPx) is particularly an efficient enzyme in the detoxification of H2O2 and other hydroperoxides by using glutathione (

APA, Harvard, Vancouver, ISO, and other styles

44

Bhabak, Krishna Pada. "Synthetic Antioxidants : Structure-Activity Correlation Studies Of Glutathione Peroxidase Mimics And Peroxynitrite Scavengers." Thesis, 2009. http://hdl.handle.net/2005/996.

Full text

Abstract:

Reactive oxygen species (ROS) such as superoxide radical anion (O2•¯), hydroxylradical (OH•), hydrogen peroxide (H2O2) and peroxynitrite (ONOO-) that are produced during the metabolism of oxygen under oxidative stress in aerobic organisms destroy several key biomolecules and lead to a number of disease states. Mammalian systems possess several effective defense mechanisms including antioxidant enzymes to detoxify these ROS. The selenocysteine-containing Glutathione peroxidase (GPx) is particularly an efficient enzyme in the detoxification of H2O2 and other hydroperoxides by using glutathione (

APA, Harvard, Vancouver, ISO, and other styles

45

BORTOLAMI, MARTINA. "Design, synthesis and in vitro evaluation of new cholinesterase inhibitors with metal-chelating and antioxidant properties as multitarget compounds for Alzheimer’s disease." Doctoral thesis, 2019. http://hdl.handle.net/11573/1354090.

Full text

Abstract:

Alzheimer’s disease (AD) is a multifactorial neurodegenerative syndrome, as many factors are involved in its pathogenesis, including: cholinergic system alterations; hyperproduction and aggregation of β-amyloid (Aβ) neurotoxic peptide; increased oxidative stress; dyshomeostasis of some bio-metals, which promote aggregation of the Aβ peptide and catalyze the formation of reactive oxygen species (ROS). Based on these considerations, series of pyrimidine, pyridine and deferiprone derivatives have been designed, synthesized and evaluated in vitro with the hypothesis that they can restore the choli

APA, Harvard, Vancouver, ISO, and other styles

46

Tomé, Sara Mirassol. "Synthesis of flavonoid-type compounds and sugar-substituted phenolics of pharmacological importance." Doctoral thesis, 2021. http://hdl.handle.net/10773/31390.

Full text

Abstract:

Flavonoids are a large class of secondary metabolites widespread in the Plant Kingdom. These natural organic compounds possess a prominent interest as therapeutic agents. Among the vast range of biological properties of both natural and synthetic derivatives are their antioxidant and anti-inflammatory activities. Among the naturally occurring oxygen containing heterocyclic compounds, flavones (2-arylchromones) assume pronounced importance due to both their spread and diverse abundance as well as their well-known wide range of pharmacological properties. Halogenated derivatives of

APA, Harvard, Vancouver, ISO, and other styles

47

Correia, Catarina Marçal. "(E)-2-styrylchromones: synthesis and evaluation of the inhibitory effects on the oxidative burst produced by human monocytes." Master's thesis, 2021. http://hdl.handle.net/10773/33584.

Full text

Abstract:

Several studies have attributed the onset and progression of several diseases, including degenerative and cardiovascular diseases, cell aging and cancer, to the production of free radicals and inflammatory processes. Consequently, a large number of investigations have been carried out in order to find new, safer and potent antioxidant and anti-inflammatory drugs, and to elucidate their corresponding mechanisms of action. The evaluation of antioxidant vs antiradicalar and anti-inflammatory activity of phenolic compounds, either of natural or synthetic origin, is nowadays an important are

APA, Harvard, Vancouver, ISO, and other styles

48

Domingues, Maria Augusta da Graça. "Synthesis, characterization and anti-oxidant activity of thio-imidate N-oxides TIO sugars." Master's thesis, 2011. http://hdl.handle.net/10400.6/3907.

Full text

Abstract:

The thioimidate N-oxide function is a rare and original function. The objective of this work is the synthesis of heterocyclic rings linked to the sugar moiety by a C-C bond and the characterization of obtained compounds. Regio and stereoselective branched-chain construction starting from D-ribose which led to the synthesis of thio-imidate N-oxide sugar derivates. The synthesis of compounds was made by several reactions, starting from D-ribose. The protection of D-ribose by isopropylidene group allows us to obtain the 2,3-O-isopropylidene-β- D-ribofuranose (1). The reduction and oxidativ

APA, Harvard, Vancouver, ISO, and other styles

49

Li, Liao. "Chemical Forays of Fungal Metabolites." Phd thesis, 2018. http://hdl.handle.net/1885/148782.

Full text

Abstract:

This thesis contains six chapters and the research presented within focuses on three parts. The first part (chapter one to three) was the isolation of antibacterial and antioxidant mushroom metabolites, and the synthesis towards analogues of discovered natural products. The following part (chapter four) was to assess antioxidant activities of synthetic compounds and investigate their SAR (structure-activity relationship), by use of a developed DPPH assay. The last part (chapter five to six) was the discovery of an abiotic halogenation reaction among a class of fungal metabolites, azaphilones.

APA, Harvard, Vancouver, ISO, and other styles

50

"Antioxidant activity of cyclolinopeptides." Thesis, 2013. http://hdl.handle.net/10388/ETD-2013-06-984.

Full text

Abstract:

Cyclolinopeptides (CLs) are hydrophobic cyclic peptides found in flaxseed. They show immunosuppressive activity, but the biological function of these compounds is largely unknown. This thesis presents the results of studies that were conducted to determine whether CLs could act as antioxidants. In the first study, flaxseed oil was passed over a silica adsorbent column to remove polar compounds. The polar compounds were then eluted from the silica absorbant using a series of increasingly polar solvents. Individual polar fractions were then added back to the silica-treated flaxseed oil and the o

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!