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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.)

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.)