Purpose: The objective of this study was to evaluate the influence ofSaccharomyces boulardiion the kinetics of fermentation for organic and conventional apple pulp and to verify the effect of the antioxidant quercetin on the response to cellular oxidative stress.Design/methodology/approach: The kinetic parameters, the content of phenolic compounds, the quantity of quercetin and the antioxidant activity were determined during the fermentation process. The effect of quercetin on cellular oxidative stress was also investigated.Findings: The content of phenolic compounds, the antioxidant activity and the quercetin concentration were higher in the organic fermented apple pulp (ORG) than in the conventional fermented apple pulp (CON). However, both apple pulps were considered ideal substrates for the growth ofS. boulardii, suggesting that they are potentially probiotic. After fermentation, the quercetin concentration in the ORG treatment and YPDQ treatment (YPD broth with 0.1 mg quercetin rhamnoside/mL) increased viability by 9%, while in the CON treatment generated there was an increase of 6% in viability, compared to the YPD control treatment (YPD broth).Originality/value: The high concentration of quercetin in the organic apple pulp supports the proposal that quercetin reduces the oxidative stress mediated by reactive oxygen species through its antioxidant action onS. boulardiithat have similarities to mammalian eukaryotic cells. These findings suggest that fermented organic apple pulp could be consumed as a potential non-dairy probiotic product.

In this study, the aim was to modify the starches of three different sweet potato varieties—Rosada Uruguaiana (RU), Rosada Canadense (RC), and Ligeirinha (L)—through in situ annealing to increase the content of slowly digestible starch (SDS), which has health benefits. The modified carbohydrate was then added to a dairy beverage fermented by Lactobacillus casei 1e (L. casei). After annealing, the starches had different physicochemical properties, and the L variety, which had the highest SDS content, was chosen for the formulation of the fermented dairy beverage. Two concentrations of modified starch (7% and 10.5%) were used in the formulations, and a sensory analysis indicated no differences in acceptance and purchase intention. The beverage containing 10.5% modified starch exhibited good physicochemical and microbiological stability. This study demonstrates the possibility of creating a functional fermented dairy beverage with high SDS content, which could potentially benefit consumers’ health.

O biflavonóide inédito 4-H-2,3-diidro-1-benzopiran-4-ona-6-[2-fenil-8-(3-metil-2-butenil)-5,7-dimetoxi-2-H-3,4-diidro-1-benzopiran-4-il]-5,7-diidroxy-8-(3-metil-2-butenil)-2-fenil, denominada toxicarina (1), a flavanona 7-O-metil glabranina (2) e a mistura de rotenóides tefrosina (3) e rotenolona (4) foram isolados e caracterizados, das raízes de Tephrosia toxicaria (Sw.) Pers. As estruturas foram determinadas por métodos espectroscópicos principalmente pelos espectros de 1H e 13C uni e bidimensionais.

The aim of this study was to verify the efficacy of different organic solvents, in the permeabilization of Saccharomyces fragilis IZ 275, by using a Central Composite Rotational Design (CCRD) 23 and Response Surface Methodology (RSM). Furthermore, we aimed to evaluate the effectiveness of the permeabilization process by monitoring lactose hydrolysis and obtaining images of non-permeabilized and permeabilized cells by Scanning Electron Microscopy (SEM). The yeast S. fragilis IZ 275 was grown in a fermentation medium composed of cheese whey, and the permeabilized cells was estimated by β-galactosidase activity. The response surface methodology was used as it is an efficient tool to optimize the permeabilization process as well as to identify the organic solvent which was most effective for this process. Our results show that the concentration and type of organic solvent, as well as permeabilization temperature and time influence the cells permeabilization process.. Considering the experimental results, the best conditions when using chloroform are a concentration of 4 % at 25 ºC during 20 min with 81.03 % lactose hydrolysis. In this study, we found that the use of ethanol for cellular permeabilization lead to obtaining β-galactosidase enzyme, a process which can be used in a large scale by the food industry, being a cheaper and more environmentally safe way of obtaining this enzyme.