published_or_final_version / Chemistry / Master / Master of Science

Orientadora: Karina Alves de Toledo / Banca: Luis Octávio Regasini / Banca: Flávia Aparecida Paina Brasil / Resumo: Rutina e Quercetina são flavonoides encontrados em diversos alimentos, incluindo aqueles indicados como complemento no tratamento de doenças inflamatórias. Durante o processo inflamatório, neutrófilos são as primeiras células a serem recrutadas por estarem diretamente relacionadas à ativação e resolução destes processos. Assim, frequentemente estas células são alvos para novos compostos anti-inflamatórios. A descrição da atividade anti-inflamatória de rutina e quercetina se estende para vários ativadores das vias clássicas dos neutrófilos. O estudo quanto aos compostos forbol ésteres, como PMA (phorbol myristate acetate), que ativam de maneira específica a sinalização da proteína quinase C, ainda são escassos.O objetivo deste trabalho foi analisar a atividade anti-inflamatória de rutina e quercetina sobre neutrófilos ativados por PMA. Para tanto, foram analisadas etapas importantes do processo inflamatório mediadas pelos neutrófilos: adesão, desgranulação, e liberação das NETs (Neutrophil Extracelular Traps). Nossos resultados demonstraram que, ativação de neutrófilos por PMA: (i) rutina e quercetina não inibem a adesão dos neutrófilos, (ii) quercetina inibe a desgranulção, (iii) ambos inibem a atividade da mieloperoxidase (MPO), assim como (iv) inibem a liberação das NETs na ausência de morte celular. Análises de docking molecular sugerem que tais eventos podem estar relacionados à geração de complexos quercetina/MPO e rutina/elastase / Abstract: Rutin and Quercetin are flavonoids found in several foods, including those indicated as a supplement in the inflammatory treatment diseases. During the inflammatory process, neutrophils are the first cells to be recruited. They are directly related to the activation and resolution of these processes. Thus, these cells often target new antiinflammatory compounds. The description of the anti-inflammatory activity of rutin and quercetin extends to several activators of classical neutrophil pathways. Studies involving forbol esters compounds, as PMA ((phorbol myristate acetate), which activate in a specific manner the protein kinase signalling, it is still poor. The aim of this study was to analyze the anti-inflammatory activity of rutin and quercetin on PMAactivated neutrophils. For this, important steps of the inflammatory process mediated by neutrophils were analyzed: adhesion, degranulation, and release of NETs (Neutrophil Extracelular Traps). Our results demonstrated that neutrophil activation by PMA: (i) rutin and quercetin did not inhibit neutrophil adhesion, (ii) quercetin inhibited degranulation, (iii) both inhibited myeloperoxidase activity (MPO), as well as (iv) both Inhibit the release of NETs in the absence of cell death. Molecular docking analyzes suggest that such events may be related to the generation of quercetin/MPO and rutin/elastase complexes / Mestre

The emerging scientific evidences on the role of food components in prevention of several chronic diseases are the momentum for shifting from a traditional focus on production to enhancement of nutritional quality. To further understand the role of these phytochemicals this dissertation describes the development of rapid analytical and isolation methods, and the effect of production systems and processing techniques on the levels of phytochemicals in citrus fruits. In the first study, a simultaneous high performance liquid chromatography (HPLC) method for the rapid analysis of amines and organic acids was developed. The simultaneous extraction and analysis of samples provides an economical method for analyzing a large number of samples. In the second study, rapid separation method of potent health beneficial phytochemicals such as polymethoxyflavones from citrus peels using flash chromatography was developed. Using the developed method, five polymethoxyflavones were separated and isolated with high purity in gram level quantity. In the third study, the levels of phytochemicals in organically and conventionally grown lemons and their storage at market simulated conditions were determined. Results suggest that organically produced citrus fruits have higher content of organic acids and flavonoids than conventionally produced. The fourth and fifth study determined the influence of household processing (blending, juicing, hand squeezing techniques) and emerging processing (high pressure processing [HPP], thermal processing) on the phytochemicals content of ‘Rio Red’ grapefruits. Fruits processed by blending had significantly higher levels of flavonoids, furocoumarins and limonin compared to juicing and hand squeezing, while HPP enabled in extending the shelf life of the processed juice without any adverse effects. Therefore, consuming grapefruit juice processed by blending may provide higher levels of health beneficial phytochemicals. The sixth study describes a rapid flash chromatography method for isolation of PMFs and furocoumarins from citrus industrial by products such as peel oil. In the seventh study the developed method was applied to isolate 10 different phytochemicals from an unexplored citrus species, Miaray mandarin (Citrus miaray TAN.). Among them, the 5,7,8,3',4' pentamethoxyflavone was isolated for the first time from the genus Citrus.

published_or_final_version / Pharmacology and Pharmacy / Master / Master of Philosophy

Introduction: Cognitive impairment (CI) in older adults refers to impairment in cognition function beyond normal aging. Previous studies have reported the effect of dietary antioxidants, especially flavonoids on cognitive function in older adults, suggesting that high dietary flavonoids intake may reduce the risk of cognitive impairment. However, most of these studies were reported in Caucasian older populations in Western countries. Moreover, some studies were positive, which others were negative studies. There was no previous study regarding dietary flavonoids and cognitive impairment among Chinese older adults. Objectives: The objectives of this study were to explore the association between dietary intake flavonoids and the risk of cognitive impairment in Chinese older adults, and to identify the independent factors associated with the risk of cognitive impairment in Chinese older adults. Method: This study was a retrospective cross-sectional study, 200 patients who fulfilled the inclusion and exclusion criteria and gave written informed consent were recruited from the Geriatric clinics in Queen Mary Hospital, Hong Kong, from 11th July to 31st October 2011. All recruited subjects were invited to attend face-to-face interviews. Brief cognitive assessments by the Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were done for all subjects. Every subject also answered a detailed questionnaire on socio-demographic, type and frequency of diet items (food frequency questionnaire) and co-morbid diseases. Main outcome measure: The primary outcome measure was cognitive function, using an education-adjusted MMSE cut-off s to categorize the subjects into two groups (i.e. normal cognitive group and cognitively impaired group). Results: 200 subjects were recruited, 104 participants (37 males and 67 females) were in the normal cognitive group and 96 subjects (22 males and 74 females) were in the cognitively impaired group. The mean amount of dietary flavonoids intake of the cognitively normal group was higher than that of the cognitively impaired group (i.e. 291.84 grams/day and 240.92 grams/day respectively; p=0.006 Mann-Whitney U test). Other common dietary nutrients were also compared between the two groups. The dietary carbohydrate (p<0.001), total sugar (p<0.001), vitamin C (p=0.001) and folic acid (p<0.001) intakes were significantly related to cognitive impairment (using chi-square statistics). After adjustment for age, gender, education, exercise pattern, the dietary flavonoids intake was not independently associated with cognitive impairment. However, after adjustment for age, education level, exercise pattern and BMI, the higher to highest quartile of dietary carbohydrate intake (184.184-1176.703g/d), high total sugar intake (0.166-35.102g/d), highest quartile of vitamin C intake (139.803-900.952mg/d), the third and fourth quartiles of folic acid intake (208.899-1544.418mcg/d) were significantly associated with reduced risks of cognitive impairment. Older adults who had regular exercise (both less and more than 30 minutes per day) had lower risk of cognitive impairment than those who never did exercise (OR= 0.361, 95% confidence interval=0.167-0.784 for less than 30 minutes/d; OR=0.137, 95% confidence interval=0.048-0.396 for more than 30 minutes/d). We also found high BMI was associated with a reduced risk of cognitive impairment with an OR of 0.897 (95% confidence interval=0.816-0.987). Besides, the increasing age was also associated with cognitive impairment (OR=1.059, 95% confidence interval=1.007-1.115). Conclusion: In summary, the present study demonstrated that the dietary flavonoids intake was not significantly associated with the risk of cognitive impairment in Chinese older adults in Hong Kong. / published_or_final_version / Medicine / Master / Master of Medical Sciences

Ląstelės metabolizme svarbų vaidmenį vaidina oksidacijos – redukcijos reakcijos, kuriose deguonis yra elektronų akceptorius. Įvairių cheminių reakcijų metu gali susidaryti ir aktyviosios deguonies formos – superoksido anijonas, vandenilio peroksidas, hidroksilo radikalas, singletinis deguonis, kurios pažeidžia įvairias biomolekules. Augalai nuo seniausių laikų yra vartojami įvairioms ligoms gydyti. Flavonoidai – tai augalinės kilmės junginiai, randami vaisiuose, daržovėse arbatose, kurie pasižymi antioksidacinėmis savybėmis. Sintetiniai antioksidantai polifenoliai labai plačiai naudojami maisto pramonėje, kaip įvairūs priedai ir konservantai. Vienas jų - kvercetinas. Kvercetino antioksidacinis poveikis priklauso nuo to, kad jis reaguoja su laisvaisiais radikalais, sudarydamas fenoksradikalus, kurie yra ne tokie aktyvūs. Tačiau aukštos kvercetino koncentracijos yra citotoksiškos, o citotoksiškumo mechanizmai, nors ir labai plačiai tyrinėjami visame pasaulyje, lieka neaiškūs. Mūsų darbo tikslas ir buvo ištirti kvercetino ir kitų flavonoidų poveikį Hep 22a linijos ląstelėms. Hep 22a ląstelių linija pasirinkta neatsitiktinai. Tai pelių hepatomos ląstelių kultūra, kuri pasižymi navikinėms ląstelėms būdingomis savybėmis – neribota proliferacija ir ląstelių migracija. Vyrauja epitelinio tipo ląstelės, kurias persėjus po oda susidaro navikai. Ląstelės gerai auga tiek in vivo, tiek in vitro. Ląstelės pailgos, prisitvirtinusios prie substrato, sudaro monosluoksnį. Tirtų flavonoidų... [toliau žr. visą tekstą] / ABSTRACT Flavonoids are widely distributed in edible plants, and considered to be dietary antioxidants. Flavonoids can protect cell from „oxidative stress“, but the same flavonoids compound could behave in two ways as an both antioxidant and prooxidant, depending on the concentration used and free radical source. Among the flavonoids, quercetin is one of the most widely studied flavonoid and has biological, pharmocological, and medicinal properties. Besides the chemopreventive effects, other biological functions of quercetin are believed to improve antioxidant defence systems in living organizms. The aim of this work was to analize the effects of flavonoids (quercetin, myricetin and morin) in Hep 22a cells. Materials and methods: 1. Cell culture cytotoxicity studies; Flavonoids and the other components were obtained from Sigma, and used as received. 2. Study with fluorescence microscope 3. Statistical analysis Results and discusion: Hep 22a cell line is a mouse hepatoma cell line, which posseses the unlimited proliferation and migration features. Quercetin concentration for 50 % death of Hep 22a cells (cL50) was 160 µM, myricetin concentration was 60 µM, and morin concentration was 190 µM,. The citotoxity of flavonoids in Hep 22a cells was partly inhibited by catalase, by the antioxidant N,N‘-diphenyl-p-phenylene diamine DPPD, desferrioxamine and by dicumarol and an inhibitor of DT-diaphorase thus showing its prooxidant character. Inhibitors of cytochromes P-450, &#945... [to full text]

One of the many ways to address health, obesity and hunger issues is genetic bio-fortification, a strategy of breeding or transforming staple crops with micronutrients and vitamins. This dissertation details efforts to bio-fortify bioactive compounds (phenols, antioxidants, condensed tannins, flavonoids and anthocyanins) in Vigna unguiculata, a staple legume grain crop. Approaches included screening of genetic variation in polyphenolic compositions to identify potential varieties and phenotypes, evaluating the impact of environment (drought stress) on these compositions and elucidating the underlying genetics of their inheritance. Our screening showed significant diversity among genotypes for phenols (2.05 –15.48 mg GAE/g), condensed tannin (0.05 -15.29 mg CE/g) and antioxidant activity (4.0 -201.8 µM TE/g). The highest levels of phenols and antioxidant activity were observed in genotypes with light brown, black and red seed coat color, and those with smooth texture and medium maturity (70-90 days). Red and black phenotypes showed the highest content of flavan-3-ols, flavonols and phenolic acids among all color groups, with values of 169 µg CE/g, 26.17 µg QHE/g, 27.14 µg GAE/g for red and 281 µg CE/g, 23 µg QHE/g and 25 GAE/g for black phenotypes. When studying the impact of drought stress, genotypeXtreatment and treatmentXyear interactions for bioactive compounds were significant when tested under irrigated and drought stress conditions. Anthocyanins showed a 14 % decrease under drought stress. The genotypes that were stable to drought stress are favorable for breeding programs in preparation towards climate change. An FTNIR method was established for high-throughput, non-destructive quantification of bioactive compounds. This was used in inheritance studies of bioactive compounds. Phenols, condensed tannins and flavonoids showed heterosis in F1 and exhibit transgressive segregation in F2 populations. The information presented in this manuscript will be useful for nutritional improvement of cowpeas, where potential genotypes and phenotypes with health benefits offered by enhanced contents of bioactive compounds can be improved further upon.

Thesis (M. Med. Sc.)--University of Hong Kong, 2007.

Thesis (Ph. D.)--Oregon State University, 1992. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.

Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Leaf 6 not included in numbering but content is complete. Vita. Includes bibliographical references (leaves 73-79). Also available on the Internet.