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Nowadays, worldwide challenges such as global warming, pollution, unsustainable consumption patterns, and scarcity of natural resources are key drivers toward future-oriented bioeconomy strategies, which rely on renewable biobased resources, such as bacterial pigments and bacterial cellulose (BC), for materials production. Therefore, the purpose of this study was to functionalize bacterial cellulose with violacein, flexirubin-type pigment, and prodigiosin and test their suitability as pH indicators, due to the pigments' sensitivity to pH alterations. The screening of the most suitable conditions to obtain the BC-pigment indicators was achieved using a full factorial design, for a more sustainable functionalization process. Then, the pH response of functionalized BC to buffer solutions was assessed, with color changes at acidic pH (BC-violacein indicator) and at alkaline pH (BC-violacein, BC-prodigiosin, and BC-flexirubin-type pigment indicators). Moreover, the indicators also revealed sensitivity to acid and base vapors. Furthermore, leaching evaluation of the produced indicators showed higher suitability for aqueous foods. Additionally, color stability of the functionalized BC indicators was carried out, after light exposure and storage at 4 °C, to evaluate the indicators' capacity to maintain color/sensitivity. Thus, BC membranes functionalized with bacterial pigments have the potential to be further developed and used as pH indicators. [ABSTRACT FROM AUTHOR]

The period from 2019 to 2022 has been defined by the COVID-19 pandemic, resulting in an unprecedented demand for and use of Personal Protective Equipment (PPE). However, the disposal of PPE without considering its environmental impact and proper waste management practices has become a growing concern. The increased demand for PPE during the pandemic and associated waste management practices have been analyzed. Additionally, the discussion around treating these residues and exploring more environmentally friendly alternatives, such as biodegradable or reusable PPE, is crucial. The extensive use of predominantly non-degradable plastics in PPE has led to their accumulation in landfills, with potential consequences for marine environments through the formation of microplastics. Therefore, this article seeks to establish a connection between these issues and the Sustainable Development Goals, emphasizing the importance of efficient management aligned with sustainable development objectives to address these emerging challenges and ensure a more sustainable future. [ABSTRACT FROM AUTHOR]

In recent years, several researchers have focused their studies on the development of sustainable biomaterials using renewable sources, including the incorporation of living biological systems. One of the best biomaterials is bacterial cellulose (BC). There are several ways to produce BC, from using a pure strain to producing the fermented drink kombucha, which has a symbiotic culture of bacteria and yeasts (SCOBY). Studies have shown that the use of agricultural waste can be a low-cost and sustainable way to create BC. This article conducts a literature review to analyze issues related to the creation of BC through kombucha production. The databases used were ScienceDirect, Scopus, Web of Science, and SpringerLink. A total of 42 articles, dated from 2018 to 2022, were referenced to write this review. The findings contributed to the discussion of three topics: (1) The production of BC through food waste (including patents in addition to the scientific literature); (2) Areas of research, sectors, and products that use BC (including research that did not use the kombucha drink, but used food waste as a source of carbon and nitrogen); and (3) Production, sustainability, and circular economy: perspectives, challenges, and trends in the use of BC (including some advantages and disadvantages of BC production through the kombucha drink). [ABSTRACT FROM AUTHOR]

The first ever nanofibers produced by the electrospinning of polyvinyl alcohol (PVA) and Spirulina platensis extracts are presented in this article. Spirulina platensis extracts were obtained by ultrasound-assisted extraction (UAE) using two different solvents: a glucose/glycerol-based natural deep eutectic solvent (NADES) and water. Through spectrophotometry analysis, it was possible to determine the pigment yield of the extractions for both extracts: phycocyanin = 3.79 ± 0.05 mg/g of dry biomass (DB); chlorophylls = 0.24 ± 0.05 mg/g DB; carotenoids = 0.13 ± 0.03 mg/g DB for the NADES/Spirulina extracts, and phycocyanin = 0.001 ± 0.0005 mg/g DB; chlorophylls = 0.10 ± 0.05 mg/g DB; carotenoids = 0.20 ± 0.05 mg/g DB for water/Spirulina extracts. Emulsions were formed by mixing the microalgae extracts in PVA (9%, w/v) at different concentrations: 5, 20, 40, and 50% (v/v). Electrospinning was carried out at the following conditions: 13 cm of distance to collector; 80 kV of applied voltage; and 85 rpm of electrode rotation. After the nanofibers were collected, they were checked under a scanning electron microscope (SEM). ImageJ was also used to determine fiber diameter and frequency. SEM results showed the formation of nanofibers for 5 and 20% (v/v) of NADES/Spirulina extract content in the electrospinning emulsions, presenting diameters of 423.52 ± 142.61 nm and 680.54 ± 271.92 nm, respectively. FTIR confirmed the presence of the NADES extracts in the nanofibers produced. Overall, the nanofibers produced showed promising antioxidant activities, with the NADES/Spirulina- and PVA-based nanofibers displaying the highest antioxidant activity (47%). The highest antimicrobial activity (89.26%) was also obtained by the NADES/Spirulina and PVA nanofibers (20%, v/v). Principal Component Analysis (PCA) revealed positive correlations between both the antioxidant and antimicrobial activities of the electrospun nanofibers, and extract content in the emulsions. Moreover, PCA also indicated positive correlations between the viscosity and conductivity of the emulsions and the diameter of the nanofibers produced. [ABSTRACT FROM AUTHOR]

Excessive use of petroleum derivatives in cosmetics, whether in compositions or packaging, predominating the use of plastics, parabens, microplastics and other polymers, has had negative environmental impacts. The cosmetics market has gained prominence in recent years and bioeconomy and circular economy policies are putting pressure on the market to use bio-based and biodegradable materials. In this context, the objective of this review article is to provide an overview of how the aggregation of sustainable actions in the cosmetic industry contributes to the fulfillment of the 2030 Agenda and how this can serve as a guide in building a more resilient and sustainable society. For that, the generation of residues during the production processes was examined and the environmental problems generated by the cosmetic industry were addressed. Then, the role of aggregating sustainable actions and innovations with regard to the achievement of the UN Sustainable Development Goals (SDGs) in the cosmetic industry were evaluated. [ABSTRACT FROM AUTHOR]

The connection with textiles is one of the oldest traditions in humanity, and in the historical scenario, textiles and clothing deal with material culture. Therefore, preservation is of the utmost importance to keep this important heritage. Packaging and protection of museological textiles is imperative due to the risks that these articles suffer, mainly concerning the attack of microorganisms that promote the acceleration of their degradation, and it is still necessary to create a proper packing material. In the present work we describe a bibliographic review about the museological scenario, focused on the packaging for preservation of textile articles, as well as the techniques usually used in preventive material conservation. Future perpsctives for the improvement in the conservation of museological textiles are also given. This research aims to produce a sustainable material based on polycaprolactone (PCL), with and without antimicrobial function by incorporating Lavandula luisieri essential oil (EO), in the form of a non-woven substrate for museological packaging. A comparison was made with the most frequently used materials, such as raw cotton and a non-woven polyester. The results demonstrated that both PCL and PCL + EO obtained a good characterization for museological application with good breaking strength and excellent whiteness index. In addition, PCL + EO showed a high bacterial reduction when compared with other protective materials frequently used in museums. Therefore, these findings emphasize the potential use of this material as an innovative protective antibacterial museological packaging solution, able to safeguard and preserve textile museum and clothing collections for longer and for future generations. [ABSTRACT FROM AUTHOR]

Nowadays, food packaging systems have shifted from a passive to an active role in which the incorporation of antimicrobial compounds into biopolymers can promote a sustainable way to reduce food spoilage and its environmental impact. Accordingly, composite materials based on oxidized-bacterial cellulose (BC) and poly(vinyl alcohol)-chitosan (PVA-CH) nanofibers were produced by needleless electrospinning and functionalized with the bacterial pigment prodigiosin (PG). Two strategies were explored, in the first approach PG was incorporated in the electrospun PVA-CH layer, and TEMPO-oxidized BC was the substrate for nanofibers deposition (BC/PVA-CH_PG composite). In the second approach, TEMPO-oxidized BC was functionalized with PG, and afterward, the PVA-CH layer was electrospun (BC_PG/PVA-CH composite). The double-layer composites obtained were characterized and the nanofibrous layers displayed smooth fibers with average diameters of 139.63 ± 65.52 nm and 140.17 ± 57.04 nm, with and without pigment incorporation, respectively. FTIR-ATR analysis confirmed BC oxidation and revealed increased intensity at specific wavelengths, after pigment incorporation. Moreover, the moderate hydrophilic behavior, as well as the high porosity exhibited by each layer, remained mostly unaffected after PG incorporation. The composites' mechanical performance and the water vapor transmission rate (WVTR) evaluation indicated the suitability of the materials for certain food packaging solutions, especially for fresh products. Additionally, the red color provided by the bacterial pigment PG on the external surface of a food packaging material is also a desirable effect, to attract the consumers' attention, creating a multifunctional material. Furthermore, the antimicrobial activity was evaluated and, PVA-CH_PG, and BC_PG layers exhibited the highest antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa. Thus, the fabricated composites can be considered for application in active food packaging, owing to PG antimicrobial potential, to prevent foodborne pathogens (with PG incorporated into the inner layer of the food packaging material, BC/PVA-CH_PG composite), but also to prevent external contamination, by tackling the exterior of food packaging materials (with PG added to the outer layer, BC_PG/PVA-CH composite). [ABSTRACT FROM AUTHOR]