This dissertation examines the effects of postharvest treatment and processing on biologically active compounds of orange juice, and ??Rio Red?? grapefruit and their ability to prevent chemically induced colon cancer in rat model. The first study evaluated the differences in flavonoid content of commercial ??made from concentrate?? (MFC) orange juices and ??not from concentrate?? (NFC) orange and grapefruit juices. Total flavonoid content of MFC orange juices (53 mg/100 mL; n = 12) was significantly (P ≤ 0.05) higher than NFC orange juices (36.5 mg/100 mL; n = 14). The second study investigated the ionizing radiation and storage effects on bioactive compounds and quality of ??Rio Red?? grapefruit. Results showed that storage and irradiation significantly (P ≤ 0.05) affected the bioactive compounds in grapefruit, however, the effect of storage was prominent. The third study examined the influence of irradiation and freeze drying on bioactive compounds of grapefruit. Irradiation of grapefruit prior to freeze drying resulted in enhanced (P ≤ 0.05) flavonoid content (naringin and narirutin). Freeze drying markedly reduced (P ≤ 0.05) lycopene content. Freeze drying and irradiation reduced (P ≤ 0.05) volatile compounds (d-limonene and myrcene), with the exception of ethanol. In the fourth study suppression of colon cancer development in Sprague Dawley rats by natural and irradiated grapefruits and their functional compounds, naringin and limonin, were evaluated.The total number of aberrant crypts (AC; P = 0.02), number of high multiplicity AC foci (ACF; P = 0.01), and proliferative index (P = 0.02) were lower and apoptosis (P = 0.02) was higher in azoxymethane (AOM) injected rats on experimental diets. However, only natural grapefruit and limonin only suppressed AOM induced expansion (P = 0.008) of proliferative zone and also enhanced apoptosis more effectively than other experimental diets indicating that natural grapefruit and limonin may serve as better chemopreventive agents compared to IGFPP and naringin. The present study indicates that postharvest quarantine doses of irradiation slightly alter composition of bioactive compounds and in turn marginally reduce the chemopreventive ability of grapefruit against the promotion stage of colon cancer. These results warrant the necessity of testing the impact of post harvest treatments on fruits and vegetables chemopreventive ability.

Flavonoids are secondary metabolites that have significant roles in plant defense and human nutrition. Glucosyltransferases (GTs) catalyze the transfer of sugars from high energy sugar donors to other substrates. Several different secondary product GTs exist in the tissues of grapefruit making it a model plant for studying their structure and function. The goal of this investigation was to determine the expression patterns of seven putative secondary product GTs during grapefruit growth and development by quantifying mRNA expression levels in the roots, stems, leaves, flowers, and mature fruit to establish whether the genes are expressed constitutively or if one or more could be expressed in a tissue specific manner and/or developmentally regulated. Six growth stages were defined from which RNA was extracted, and expression levels were quantified by standardized densitometry of gene-specific RT-PCR products. Results show that there were variable degrees of PGT expression in different tissues and at different developmental stages. These results add to the growing knowledge base of dynamics of expression and potential regulation of secondary metabolism in Citrus paradisi.

Made available in DSpace on 2015-04-22T22:01:59Z (GMT). No. of bitstreams: 1 Dissertacao- Lyege Magalhaes.pdf: 5975842 bytes, checksum: 72a22c7838dd7e60cbd8fa361b73896a (MD5) Previous issue date: 2009-12-21 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The Meliaceae family has pantropical occurrence and include around 700 species distributed in 50 genus. The main secondary metabolites of the family are limonoids, terpenoids, steroids e and flavonoids. The Guarea genus found in Tropical America and Africa contains about 50 species, of which around 10 species have chemical studies. The studies showed that sesqui-, di-, triterpenes and limonoids are the main constituents. This work aimed to evaluate the chemical constituents of Guarea convergens, G. scabra, G. silvatica (volatile) and G. humaitensis (volatile and non-volatile) and the activity against Aedes aegypti, the main species transmitter of the dengue. In this manner, vegetal samples collected in the Ducke Reserve were submitted to hydrodistillation to obtain essential oil and/or macerated to obtain the organic extract. The essential oils obtained showed the predominance of sesquiterpenes. In the branches of G. convergens the majority components were α-santalene (26.26%), α-copaene (14.61%), drim-7,9 (11)-diene (6.85%) and β-santalene (6.32%), and in the oil of G. humaitensis branches predominated the caryophyllene epoxide (40.91%), humulene epoxide II (14.43%) and β-bisabolene (8.36%). In leaves of G. scabra, the majority components were cis-caryophyllene (33.37%) and α-trans-bergamotene (11.88%), and in G. silvatica, caryophyllene epoxide (36.54% leaves; 8.57% branches), espatulenol (14.34% branches and 4.17% leaves) and β-elemene (6.20% leaves), further the kaurene diterpene in leaves (15.61%). The phytochemical study of extracts of leaves and branches of G. humaitensis lead to obtaining a mixture of sesquiterpenes caryophyllene epoxide and humulene epoxide II, mixture of steroids β-sitosterol and stigmasterol, a new limonoid of the mexicanolide type, 2-deoxygrandifolide A, the coumarin scopoletin and the triterpene cycloart-23-ene-3β,25-diol. Among essential oils tested against the larvae of. A. aegypti, the oil of the G. humaitensis branches presented the best larvicidal activity (49,0 CL50= μg.mL-1). / A família Meliaceae tem ocorrência pantropical e compreende cerca de 700 espécies distribuídas em 50 gêneros. Os principais metabólitos secundários da família são limonóides, terpenóides, esteróides e flavonóides. O gênero Guarea compreende cerca de 50 espécies encontradas na América tropical e na África cujos estudos sobre os constituintes químicos são restritos a cerca de 10 espécies, onde foram identificados principalmente sesqui, di e triterpenos e limonóides. Este trabalho visou avaliar os constituintes químicos de Guarea convergens, G. scabra, G. silvatica (voláteis) e G. humaitensis (voláteis e fixos) e a atividade sobre Aedes aegypti, principal espécie transmissora da dengue. Assim, amostras vegetais coletadas na Reserva Ducke foram submetidas a hidrodestilação para obtenção de óleos essenciais e/ou macerados para obtenção de extratos orgânicos. Os óleos essenciais obtidos mostraram a predominância de sesquiterpenos. Nos galhos de G. convergens os majoritários foram α-santaleno (26,26%), α-copaeno (14,61%), drima-7,9(11)-dieno (6,85%) e β-santaleno (6,32%), e no óleo dos galhos de G. humaitensis predominaram o epóxido de cariofileno (40,91%), epóxido de humuleno II (14,43%) e β-bisaboleno (8,36%). Em folhas de G. scabra, os componentes majoritários foram cis-cariofileno (33,37%) e α-trans-bergamotemo (11,88%) e G. silvatica epóxido de cariofileno (36,54% folhas; 8,57% galhos), espatulenol (14,34% galhos e 4,17% folhas) e β-elemeno (6,20% folhas), além do diterpeno kaureno em folhas (15,61%). O estudo fitoquímico dos extratos de folhas e galhos de G. humaitensis conduziu a obtenção de uma mistura dos sesquiterpenos epóxido de cariofileno e epóxido de humuleno II, mistura dos esteróides β-sitosterol e estigmasterol, um novo limonóide do tipo mexicanolideo, 2-desoxigrandifolídeo A, a cumarina escopoletina e o triterpeno cicloar-23-en-3β,25-diol. Dentre os óleos essenciais testados frente às larvas de A. aegypti, o óleo dos galhos de G. humaitensis apresentou a maior atividade larvicida (CL50= 49,0 μg.mL-1).

Made available in DSpace on 2016-06-02T19:23:02Z (GMT). No. of bitstreams: 1 6668.pdf: 2073017 bytes, checksum: 8ec4f9ade1f9ee1c27b9d53f7a52d371 (MD5) Previous issue date: 2015-03-30 / Financiadora de Estudos e Projetos / Cancer is among the leading causes of death in the world and breast cancer is the type of cancer that affects more women. The treatment of this disorder requires a careful selection of one or more methods of intervention. The majority of drugs currently used in chemotherapy causes DNA damage in tumor cells and also in normal cells, therefore the development of new chemotherapeutic agents is challenging, since these chemotherapeutic agents should be able to kill or inhibit the growth only of tumor cells. From ancient times until today plants and their products have been used for the treatment of diseases, thus the natural compounds may provide new opportunities for the development of cancer drugs. Cedrelone is an isolated limonoid from methanol extract of Trichilia catigua aryl, a native Brazilian plant that grows abundantly in various regions of the country and is popularly known as "cedrinho", "catuaba" or "catiguá". Studies have shown that cedrelone has insecticidal and antifungal activity and previous studies performed by our research group have demonstrated that cedrelone is able to inhibit proliferation, colony formation, cell adhesion, migration, invasion and moreover, to induce apoptosis in triple negative breast cancer cells from the line MDAMB- 231. Therefore, the aim of this study was to identify the mechanism of action of cedrelone in triple negative breast tumor cells, MDA-MB-231, through cedrelone analysis, and through cell morphology assay, colony formation, apoptosis assays such as DNA fragmentation and nuclear fragmentation, cell cycle, qRT-PCR and western blotting. The results demonstrate that cedrelone has an affinity for biological membranes and no antioxidant activity. Furthermore, cedrelone is capable of inducing morphological changes, reduce the number and size of colonies and induce apoptosis by increasing the gene expression of pro-apoptotic protein Bax and decreasing gene expression of anti-apoptotic Bcl-2 in MDA-MB-231. These results indicate that cedrelone has immense potential in cancer therapy based on their antiproliferative and apoptosis inducing effects. / O câncer está entre as maiores causas de morte do mundo, sendo que o câncer de mama é o tipo de câncer que mais acomete mulheres. O tratamento dessa doença requer uma cuidadosa seleção de um ou mais métodos de intervenção. A maioria das drogas usadas em quimioterapia atualmente provoca danos no DNA, tanto das células tumorais, como também das células normais, portanto o desenvolvimento de novos quimioterápicos é um desafio, uma vez que esses quimioterápicos devem ser capazes de agir seletivamente para matar ou inibir o crescimento apenas de células tumorais. Desde a antiguidade até hoje as plantas e seus produtos vêm sendo utilizados para o tratamento das doenças, sendo assim os compostos naturais podem proporcionar novas oportunidades para o desenvolvimento de medicamentos contra o câncer. A cedrelona é um limonóide isolado do extrato metanólico do arilo de Trichilia catigua, uma planta nativa da flora brasileira que cresce abundantemente em várias regiões do país e que é popularmente conhecida como cedrinho , catuaba ou catiguá . Estudos demonstram que a cedrelona apresenta atividade inseticida e antifúngica, e em um estudo preliminar verificamos que a cedrelona inibe a proliferação de células tumorais da linhagem MDA-MB-231 com mais seletividade do que inibe a proliferação de fibroblastos humanos, inibe significativamente a adesão das células MDA-MB-231 ao colágeno tipo I, e também possui um potencial excelente contra a migração e a invasão das células MDA-MB-231. A cedrelona também é capaz de induzir a apoptose em células da linhagem MDA-MB- 231. Portanto, o objetivo do presente trabalho foi identificar o mecanismo de ação da cedrelona em células tumorais de mama triplo negativas, da linhagem MDA-MB-231, por meio de análises da cedrelona, por meio do coeficiente de partição e do ensaio de atividade antioxidante e de ensaios de morfologia celular, formação de colônia, apoptose, como o de fragmentação de DNA e o de fragmentação nuclear, ciclo celular, pcr em tem real e western blotting. Os resultados demonstram que a cedrelona possui afinidade com membranas biológicas e não apresenta atividade antioxidante. Ainda, a cedrelona é capaz de induzir modificações morfológicas, diminuir o número e tamanho de colônias e induzir a apoptose aumentando a expressão gênica da proteína próapoptótica Bax e diminuindo a expressão gênica da proteína anti-apoptótica Bcl-2 nas células tumorais de mama triplo negativas, da linhagem MDA-MB-231. Esses resultados indicam que a cedrelona tem potencial na terapia contra o câncer com base em sua ação antiproliferativa e efeitos de indução da apoptose.