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http://hdl.handle.net/1843/SFSA-AXSVDW| Type: | Tese de Doutorado |
| Title: | Estudo fitoquímico e atividade biológica de constituintes das folhas e galhos de Maytenus robusta (Celastraceae) |
| Authors: | Grasiely Faria de Sousa |
| First Advisor: | Lucienir Pains Duarte |
| First Co-advisor: | Gracia Divina de Fatima Silva |
| First Referee: | Dorila Pilo Veloso |
| Second Referee: | Rosemeire Brondi Alves |
| Third Referee: | Silvia Ribeiro de Souza |
| metadata.dc.contributor.referee4: | Antonio Jacinto Demuner |
| Abstract: | O estudo fitoquímico de folhas e galhos de Maytenus robusta resultou no isolamento de 13 triterpenos pentacíclicos: 3-oxofriedelano (MR01), 3ß- hidroxifriedelano (MR02), 3ß,11ß-di-hidroxifriedelano (MR03), taraxerol (MR04),3,16-dioxofriedelano (MR09), 3-oxo-29-hidroxifriedelano (MR10), 3,16-dioxo-12[alfa]-hidroxifriedelano (MR11), 3,16-dioxo-29-hidroxifriedelano (MR12), 3,16-dioxofriedelan-1-eno (MR13), 3-oxo-16ß,29-di-hidroxifriedelano (MR14), 1[alfa],29-dihidroxi-3-oxofriedelano (MR15), 3-oxo-12[alfa],29-di-hidroxifriedelano (MR16) e 3-oxo-16ß,28,29-tri-hidroxifriedelano (MR17). Também foram isolados o esteroide ß-sitosterol (MR05) e os flavonoides canferol (MR06), canferol-3-O-ß-Dglicopiranosil-(1-3)-[alfa]-L-ramnopiranosil-(1-2)-ß-D-glicopiranosídeo (MR07) e quercetina-3-O-ß-D-glicopiranosil-(1-3)-[alfa]-L-ramnopiranosil-(1-2)-ß-D-glicopiranosídeo(MR08). Os triterpenos MR12, MR13, MR14, MR15 e MR17 e os flavonoides MR07 e MR08 são inéditos. Os triterpenos MR09, MR10, MR12,MR14 e MR16 foram submetidos a reações de redução empregando boroidretode sódio como agente redutor e foi possível obter compostos novos com potencial atividade biológica. O estudo da atividade biológica de extratos e compostosisolados consistiu da avaliação da citotoxicidade in vitro, da atividade antiinflamatória,da atividade antimicrobiana (antibacteriana, antifúngica e leishmanicida) e da atividade de inibição da enzima acetilcolinesterase (AChE). Os triterpenos MR01, MR02, MR09, MR10, MR12 e MR14 apresentaram atividade citotóxica in vitro frente a células 4T1. No ensaio de atividade antiinflamatória MR09, MR10, MR12 e MR14 foram capazes de reduzir o edema de pata de camundongos produzido por carragenina. Os extratos metanólicos de folhas e galhos também apresentaram atividade anti-inflamatória. O estudo fitoquímico e biológico de M. robusta contribuiu para conhecer mais sobre afamília Celastraceae e mostrar o potencial biológico da espécie. |
| Abstract: | The phytochemical study of the leaves and branches from Maytenus robusta resulted in the isolation of thirteen pentacyclic triterpenes: 3-oxofriedelane (MR01), 3ß-hydroxyfriedelane (MR02), 3ß11ß-dihydroxyfriedelane (MR03), taraxerol (MR04), 3,16-dioxofriedelane (MR09), 3-oxo-29-hydroxyfriedelane (MR10), 3,16-dioxo-12-hydroxyfriedelane (MR11), 3,16-dioxo-29-hydroxyfriedelane (MR12), 3,16-dioxo-friedelan-1-ene (MR13), 3-oxo-16,29-di-hydroxyfriedelane (MR14), 1[alfa],29-di-hydroxy-3-oxofriedelane (MR15), 3-oxo-12[alfa],29-dihydroxyfriedelane (MR16) and 3-oxo-16,28,29-trihydroxyfriedelane (MR17). The steroid sitosterol and the flavonoids kaempferol (MR06), kaempferol-3-O-ß-D-glucopyranosyl-(13)-ß-L- rhamnopyranosyl-(12)-ß-D-glucopyranoside (MR07) and quercetin-3-O-ß-D-glucopyranosyl-(13)-[alfa]-L-rhamnopyranosyl-(12)-ß-D-glucopyranoside (MR08) were also isolated. The triterpenes MR12, MR13, MR14, MR15 and MR17 and the flavonoids MR07 and MR08 are new compounds. The triterpenes MR09, MR10, MR12, MR14 and MR16 were submitted to reduction reaction using sodium borohydride as reducing agent and it was possible to obtain new compounds withbiological potential. The study of the biological activity of crude extracts and isolated compounds consisted of the evaluation of in vitro cytotoxic property, antiinflammatory, antimicrobial (antibacterial, antifungal and leishmanicidal) and acetylcholinesterase inhibitory activities. The triterpenes MR01, MR02, MR09, MR10, MR12 and MR14 presented in vitro cytotoxicity activity against 4T1 cells. In the anti-inflammatory activity study, MR09, MR10, MR12 and MR14 were able to reduce the carrageenan-induced paw edema in rats. The methanolic extracts fromleaves and branches also exhibit anti-inflammatory activity. The phytochemical and biological studies of the M. robusta contributed to know more about Celastraceae family and show the biological potential of this species. |
| Subject: | Química orgânica Maytenus Brasil Matéria médica vegetal Flavonoides Produtos naturais |
| language: | Português |
| Publisher: | Universidade Federal de Minas Gerais |
| Publisher Initials: | UFMG |
| Rights: | Acesso Aberto |
| URI: | http://hdl.handle.net/1843/SFSA-AXSVDW |
| Issue Date: | 17-Feb-2016 |
| Appears in Collections: | Teses de Doutorado |
Files in This Item:
| File | Size | Format | |
|---|---|---|---|
| grasiely_faria_de_sousa___tese__1.pdf | 21.05 MB | Adobe PDF | View/Open |
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