Bacterial cellulose (BC) is a natural polymer with properties suitable for tissue engineering and possible applications in scaffold production. However, current procedures have limitations in obtaining BC pellicles with the desired structural, physical, and mechanical properties. Thus, this study analyzed the optimal culture conditions of BC membranes and two types of processing: draining and oven-drying. The aim was to obtain BC membranes with properties suitable for a wound dressing material. Two studies were carried out. In the preliminary study, the medium (100 mL) was inoculated with varying volumes (1, 2, 3, 4, and 5 mL) and incubated statically for different periods (3, 6, 9, 12, and 18 days), using a full factorial experimental design. Thickness, uniformity, weight, and yield were evaluated. In the optimization study, a Box–Behnken design was used. Two independent variables were used: inoculum volume (X₁: 1, 3, and 5 mL) and fermentation period (X₂: 6, 12, and 18 d) to determine the target response variables: thickness, swelling ratio, drug release, fiber diameter, tensile strength, and Young’s modulus for both dry and moist BC membranes. The mathematical modelling of the effect of the two independent variables was performed by response surface methodology (RSM). The obtained models were validated with new experimental values and confirmed for all tested properties, except Young’s modulus of oven-dried BC. Thus, the optimal properties in terms of a scaffold material of the moist BC were obtained with an inoculum volume of 5% (v/v) and 16 d of fermentation. While, for the oven-dried membranes, optimal properties were obtained with a 4% (v/v) and 14 d of fermentation.

The use of bacterial cellulose (BC) as scaffold for active biofilms is one of the most interesting applications, especially for the biomedical and food industries. However, there are currently few studies evaluating the potential of incorporating herbal extracts into various biomaterials, including BC. Thus, the aim of this study is to report a screening of the total phenolic content and antioxidant and antimicrobial activity of ethanolic extracts of oregano, rosemary, parsley, and lovage. At the same time, the bioactive potential of BC enriched with the four ethanolic extracts is described. Microwave-assisted extraction was used to extract bioactive compounds from the four selected herbs. The physical, mechanical, structural, and chemical properties of BC were also assessed. Next, BC was enriched with the extracts, and their effect against Escherichia coli, Staphylococcus aureus, and Candida albicans was evaluated. The results showed that the bioactivity of the herbs varied significantly, with rosemary extract being the most bioactive. The BC films possessed good mechanical properties, and a three-dimensional network fibrillar structure appropriate for ethanolic-extract incorporation. The BC samples enriched with rosemary extracts had the highest antibacterial activity against S. aureus, while E. coli. and C. albicans seemed to be resistant to all extracts, regardless of herbs.

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Plums are widely known to be a good source of bioactive phytochemicals, among which are anthocyanins that are mainly found in the peels of red-purple varieties. Plum products, such as juices, jams, prunes, and pomace, resulting from juicing, still contain a significant amount of anthocyanins. But their content and profile vary with an array of factors, including the extraction procedure employed for their isolation and purification. Two types of extraction methods are usually employed to extract anthocyanins from plums, plum products, and by-products: conventional solvent extraction and new non-conventional methods, which can sometimes be paired with the conventional techniques. Solvent extraction is usually performed with methanol and ethanol, but high concentrations and large volumes are needed to obtain yields relevant for industrial use. However, methanol is not generally recognized as safe (GRAS), and extensive research is currently being conducted to develop new, non-conventional methods that are environmentally friendly, rapid, and easy to perform. Two promising novel procedures among these methods are ultrasound- and microwave-assisted extraction methods. Several studies proposed optimized novel extraction methods, including pre-extraction steps, but they are rather scarce and there generally appears to be a lack of consensus. Additionally, the expression of the results is largely unstandardized, which affects the accuracy and precision of the anthocyanins quantification and profile identification.