Fermentabilidade de frutanos da cebola (Allium cepa L.) estudo in vivo, in vitro e do efeito trófico no intestino grosso [thesis]

Grazieli Benedetti Pascoal
Farmacêuticas da USP, por tornarem possível a realização do curso de doutorado. Aos funcionários do Biotério da FCF/IQ-USP, em especial ao Wagner, pelo apoio e, principalmente, pela grande amizade. A empresa Liotécnica Ltda pelo fornecimento da matéria-prima. da USP, pela orientação, amizade e por disponibilizar a estrutura do laboratório para a realização da pesquisa. Meus agradecimentos, também, ao Cruz Alberto Junior, técnico do laboratório. A todos meus amigos e parentes que, de alguma
more » ... que, de alguma maneira, me ajudaram na realização deste trabalho. Abstract Fructans are unavailable carbohydrates, c1assified as soluble dietary fiber and prebiotics. They arrive intact in the large intestine (LI) and are fermented by the microbiota. This fermentation mainly produces short chain fatty acids (SCFA), gases and biomass. The objectives were evaluation of the in vitro and in vivo fermentation of onion fructans (Allium cepa L.) and their effect in the large intestine of rats. Male Wistar rats received, for 38 days, control diet (CO) or onion supplemented diet (10% fructans) (FO). In the in vivo fermentation were evaluated: faeces weight and moisture, moisture of caecal content, SCFA, cecum weight and wall and pH. In parallel, fragments of cecum and colon were collected for morphometric and cellular proliferation evaluation. In the in vitro fermentation, non-digestible fractions of CO and FO were evaluated under different parameters, such as: pH, SCFA, fermentability and non-fermentable residues. In vivo fermentation caused, in the 10% fructans group in relation to the control group, the following effects: a significant increase in faeces weight and moisture, in the moisture of caecal content, in cecum weight and wall, in the concentration of SCFA and a decrease in the caecal pH. The in vitro fermentation showed both quantitative and qualitative changes of ali fermented substracts. The FO presented greater fermentability when compared to the CO, according to ali variables analyzed. The 10% fructans group presented greater depth and fission of caecal crypts and metaphasic index in relation to the control group. No microscopic changes were noticed in the colon between the groups. The results indicated that the ingestion of fructans caused significant changes on the fermentative parameters, both in vivo (rats) and in vitro fermentation, and on cell proliferation in the cecum. In vitro fermentation indicated a possible fermentative behavior of the substracts and the FO had greater fermentability than the CO. These results were confirmed in vivo, once the 10% fructans group presented an increase in the SCFA production compared to the control group. The increase in butyrate might have caused the trophic effect of the cecum, which was noticed by the increase in weight and cellular proliferation.
doi:10.11606/t.9.2017.tde-12072017-121230 fatcat:tqkzo6z7tff33ftfa74buzlfhi