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The industrial residue of cashew apple juice processing (MRC) was evaluated as an alternative medium for bacterial cellulose (BC) production by Komagataeibacter xylinus ATCC 53582 and Komagataeibacter xylinus ARS B42. The synthetic Hestrin-Schramm medium (MHS) was used as a control for growing and BC production. First, BC production was assessed after 4, 6, 8, 10, and 12 days under static culture. After 12 days of cultivation, K. xylinus ATCC 53582 produced the highest BC titer in MHS (3.1 g·L -1 ) and MRC (3 g·L -1 ), while significant productivity was attained at 6 days of fermentation. To understand the effect of culture medium and fermentation time on the properties of the obtained films, BC produced at 4, 6, or 8 days were submitted to infrared spectroscopy with Fourier transform, thermogravimetry, mechanical tests, water absorption capacity, scanning electron microscopy, degree of polymerization and X-ray diffraction. The properties of BC synthesized in MRC were identical to those of BC from MHS, according to structural, physical, and thermal studies. MRC, on the other hand, allows the production of BC with a high water absorption capacity when compared to MHS. Despite the lower titer (0.88 g·L -1 ) achieved in MRC, the BC from K. xylinus ARS B42 presented a high thermal resistance and a remarkable absorption capacity (14664 %), suggesting that it might be used as a superabsorbent biomaterial., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The lipolytic yeast Yarrowia lipolytica produces cell-wall-associated lipases, namely Lip7p and Lip8p, that could have interesting properties as catalyst either in free (released lipase fraction-RLF) or cell-associated (cell-bound lipase fraction-CBLF) forms. Herein, a mixture of waste soybean frying oil, yeast extract and bactopeptone was found to favor the enzyme production. Best parameters for lipase activation and release from the cell wall by means of acoustic wave treatment were defined as: 26 W/cm 2 for 1 min for CBLF and 52 W/cm 2 for 2 min for RLF. Optimal pH and temperature values for lipase activity together with storage conditions were similar for both the free enzyme and cell-associated one: pH 7.0; T = 37 °C; and > 70% residual activity for 60 days at 4, - 4 °C and for 15 days at 30 °C.

We combined the chemical and physical methods of papain immobilization through the aldehyde groups available on oxidized bacterial cellulose (OxBC) to provide high proteolytic activity for future applications as bioactive dressing. Bacterial cellulose (BC) was obtained by the fermentation of Komagataeibacter hansenii in Hestrin-Schramm medium for 5 days, followed by purification and oxidation using NaIO 4 . Surface response methodology was used to optimize papain immobilization (2%, w/v) for 24 h. The independent variables: pH (3-7) and temperature (5 to 45 °C) were investigated. The mathematically validated optimal conditions of 45 °C and pH 7 had a statistical effect on the immobilization yield (IY) of papain in OxBC (52.9%). These ideal conditions were also used for papain immobilization in BC (unoxidized). The IY of 9.1% was lower than that of OxBC. OxBC-Papain and BC-Papain were investigated using thermal analysis, confocal microscopy, and diffusion testing. The OxBC support exhibited a more interactive chemical structure than the BC support, and was capable of immobilizing papain by covalent bonds (-C-NHR) and adsorption (ion exchange), with 93.3% recovered activity, 49.4% immobilization efficiency, and better thermal stability. Papain immobilized to OxBC by adsorption displayed 53% widespread papain activity. The results indicate the potential of prolonged bioactivity in debrided chronic wounds., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest and that the manuscript has not been published elsewhere, is not under editorial review for publication elsewhere, and is not being submitted simultaneously to another journal., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Effect of sonication on the quality parameters of juçara, banana and strawberry smoothie was evaluated using a rotational central composite design with power (73.5-250.0 W) and time (7-36 min) as independent variables. The sonicated smoothie was evaluated regarding anthocyanins, instrumental color and rheological and physicochemical parameters. Within the evaluated processing conditions, 86% of anthocyanins were retained. The pH and acidity of the smoothie wasn't affected by the independent variables. Regarding instrumental color parameters, only luminosity was affected by the operational conditions. The cavitation phenomenon decreased the apparent viscosity of the smoothie. The sonicated smoothie presented non-Newtonian behavior, with characteristics of a pseudoplastic fluid (n < 1) in all treatments and control. Taking into account that the highest anthocyanin retention was observed at 147 W for 2 min, this condition was the most recommended for the processing of the product., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Association of Food Scientists & Technologists (India) 2019.)

In the present work, the bioaccessibility of the main phenolic compounds of a juçara, banana and strawberry homogenized smoothie (control), subjected to pasteurization and sonication, was evaluated. The smoothie was also evaluated in terms of its main chemical and physical characteristics. Pasteurized smoothie showed higher apparent viscosity, as well as higher initial shear stress when compared to the control and sonicated samples. The increase in the apparent viscosity of the pasteurized smoothie was associated with the smaller particle size of this sample (68 μm). These characteristics conferred to the pasteurized smoothie higher physical stability than the control and sonicated smoothies. Phenolic compounds bioaccessibility was higher in the pasteurized and sonicated smoothies than in the control sample, which confirmed the positive effect of the treatments for the preservation of these compounds after gastrointestinal digestion. Compared to the sonication process, the pasteurization provided higher total phenolic compounds bioaccessibility (47%), as well as of ferulic (16%) and ellagic (80%) acids. Antioxidant capacity was higher in gastric digest for all the samples evaluated by ABTS assay. These results confirm the importance of processing on the physical stability and phenolic compounds bioaccessibility of the juçara-based smoothie, standing out the thermally treated product., (© Association of Food Scientists & Technologists (India) 2019.)

The aim of the present study concerns the development, characterization and sensory evaluation of a dual-functional whey hydrolysate. Four concentrations of commercial pepsin (0.48%, 0.95%, 1.43%, 1.91% w/w) were evaluated. The hydrolyses curves and the Reversed-Phase High Performance Liquid Chromatography analyses showed a direct relationship between enzyme concentration and degree of hydrolysis. Through mass spectrometry 21 peptides were identified and 5 of them have never been described in the literature before. The hydrolysate produced (PC3) induced a vascular relaxation of 65.02% in phenylephrine-contracted rat aortic rings. PC3 powder presented a homogeneous aspect with a mean particle size of 86.39 μm, high water solubility (>92%) in a wide pH range (1-12) and an increase of 33% in oil absorption capacity, when compared to the unhydrolyzed product. Sensory analysis showed a high acceptance (7.6 in a 9-point hedonic scale) of the hydrolysate among 100 consumers. The results brought the possibility of developing a whey hydrolysate with high vasorelaxant activity, great technological properties and sensory appeal, as an interesting dual-functional ingredient to be incorporated into food products., (Copyright © 2019 Elsevier Ltd. All rights reserved.)