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Considering the sustainable development goals to reduce environmental impact, sustainable sensors based on natural polymers are a priority as the large im plementation of these materials is required considering the Internet of Things (IoT) paradigm. In this context, the present work reports on sustainable blends based on collagen and different ionic liquids (ILs), including ([Ch][DHP], [Ch][TSI], [Ch][Seri]) and ([Emim][TFSI]), processed with varying contents and types of ILs in order to tailor the electrical response. Varying IL types and contents leads to different interactions with the collagen polymer matrix and, therefore, to varying mechanical, thermal, and electrical properties. Collagen/[Ch][Seri] samples display the most pronounced decrease of the tensile strength (3.2 ± 0.4 MPa) and an increase of the elongation at break (50.6 ± 1.5%). The best ionic conductivity value of 0.023 mS cm–1 has been obtained for the sample with 40 wt % of the IL [Ch][Seri]. The functional response of the collagen–IL films has been demonstrated on a resistive touch sensor whose response depends on the ionic conductivity, being suitable for the next generation of sustainable touch sensing devices. Grant PID2021-124294OB-C22 funded by MCI/AEI10.13039/501100011033 and by “ERDF A way of making Europe”. This work was supported by the Basque Government through the research groups of the Basque university system (IT1658-22). This work was also supported by the Portuguese Foundation for Science and Technology (FCT) under strategic funding UIDB/04650/2020, UID/FIS/04650/2021, projects MIT-EXPL/TDI/0033/2021 and POCI-01-0247-FEDER-046985.

Characteristics of edible/biodegradable film based on salmon frame protein isolate (SFPI), a processing by-product, containing glycerol at two different concentrations (50 and 65% by weight of protein) with and without 30% squalene (by weight of protein) were investigated. Without squalene, the SFPI film generally had higher hydrophilicity when higher concentration of glycerol was used as indicated by higher (p < 0.05) water-vapour permeability (WVP). The addition of squalene augmented yellowness and hydrophobicity of SFPI film as indicated by higher b* colour coordinate and lower WVP (p < 0.05), respectively, in comparison to those without squalene. The squalene also promoted the interactions in SFPI film matrix as revealed by Fourier-transform infrared spectra. These interactions were related to a superior mechanical properties, high barrier properties, and increased thermal resistance of the resulting SFPI film. Therefore, the addition of 30% squalene along with 50% glycerol as plasticiser improved physicochemical, mechanical, barrier, and thermal properties of SFPI film, which could be used as an alternative film for edible/biodegradable food packaging.

Cellulose-containing residue from agar production was incorporated as a filler into soy protein-based hydrogels and revalorized without further purification. Rheological assessment of these hydrogels was carried out in order to confirm their shear-thinning behavior and their suitability for 3D printing. It was observed that all hydrogels behaved as weak gels, which are suitable for 3D printing and have good printability and shape fidelity. The addition of cellulose did not cause chemical crosslinking but physical interactions, which led to morphological changes, thereby promoting hardness and shape recovery of the 3D-printed products. The hydrogel with the highest residue content (8 wt %) showed the highest value (78%) in shape recovery. Furthermore, the physicochemical characterization of these 3D-printed products revealed that although they have high swelling capacity, they preserve their integrity in wet conditions. These results suggested the potential of the 3D-printed products developed using residues without further purification to promote circular economy, increasing the efficiency in resources utilization.

Chitosan-pectin films with iron oxide (Fe3O4) magnetic nanoparticles were prepared by solution casting in order to produce biopolymer based magnetically active materials. Infrared (FTIR) spectra indicated physical interactions between the matrix and nanoparticles, corroborated by differential scanning calorimetry (DSC) results. In addition, thermal characterization suggested that the interactions between chitosan, pectin and the nanoparticles resulted in a less compact structure, influencing the film mechanical properties. Regarding vibrating-sample magnetometry (VSM) and electrical analysis, chitosan-pectin films with Fe3O4 nanoparticles showed ferrimagnetic behavior, with an increase of the dielectric constant as the nanoparticle concentration increased. Furthermore, films displayed enhanced antimicrobial activity against Escherichia coli (Gram-negative) and Staphylococcus epidermidis (Gram-positive) bacteria. Therefore, chitosan-pectin films with Fe3O4 magnetic nanoparticles provide promising results for active and intelligent food packaging applications., This research was funded by MCI/AEI/FEDER, UE, grant number RTI2018-097100-B C22. This work was also supported by the Portuguese Foundation for Science and Technology (FCT) under strategic funding UIDB/04650/2020, UID/FIS/04650/2021, project PTDC/FIS-MAC/28157/2017, and Investigator FCT Contracts 2020.02915.CEECIND (D.M.C) and 2020.04028.CEECIND (C.M.C.) funded by national funds through FCT and by the ERDF through the COMPETE2020-Programa Operacional Competitividade e Internacionalização (POCI). The authors also acknowledge funding from the Basque Government Industry and Education Department under the ELKARTEK program. Thanks are also due to the Advanced Research Facilities (SGIker) from the UPV/EHU.

Sterilization is a crucial step in the process of developing bioinks for tissue engineering applications. In this work, alginate/gelatin inks were subjected to three sterilization methods: ultraviolet (UV) radiation, filtration (FILT), and autoclaving (AUTO). In addition, to simulate the sterilization effect in a real environment, inks were formulated in two different media, specifically, Dulbecco’s Modified Eagle’s Medium (DMEM) and phosphate-buffered saline (PBS). First, rheological tests were performed to evaluate the flow properties of the inks, and we observed that UV samples showed shear thinning behavior, which was favorable for three dimensional (3D) printing. Furthermore, the 3D-printed constructs developed with UV inks showed better shape and size fidelity than those obtained with FILT and AUTO. In order to relate this behavior to the material structure, Fourier transform infrared (FTIR) analysis was carried out and the predominant conformation in protein was determined by deconvolution of the amide I band, which confirmed that the prevalence of a-helix structure was greater for UV samples. This work highlights the relevance of sterilization processes, which are essential for biomedical applications, in the research field of bioinks Authors thank Basque Government (IT1658-22 and KK2022-00019) for the funding. T.C. also thanks Basque Government for her fellowship (PRE_2021_1_0254).

Euskadiko gaztandegietan esne-gazur ugari sortzen da eta honen isurketak kalteak eragin ditzake ingurumenean. Horregatik, ikerketa honen helburua film biodegradagarriak ekoiztea da, esne-gazuraren proteina erabiliz. Elikagaien industriako bio-hondakinetatik datorren proteinan oinarritutako elikadura-ontzien alternatiba honek, hondakinen kopurua murrizteaz gain elikagaien bizitza erabilgarria handitzea du helburu. Esne-gazuraren proteinan oinarritutako filmak sortzeko, hainbat prozesatze-metodo erabili daitezke eta lan honetan konpresioa aukeratu da, ekoizpen-denborak murrizteko eta prozesu iraunkorragoak sustatzeko. Filmen eraketa-prozesua optimizatu ondoren, lortutako filmen propietate fisiko-kimikoak, optikoak, mekanikoak eta hesi propietateak aztertu dira. Horretaz gain, filmen ingurumen-inpaktuaren azterketa egin da.

Thermocompression was employed to prepare citric acid-crosslinked chitosan films with Aloe vera (AV) as bioactive compound. Films were easy to handle and mechanical properties did not change with the addition of AV up to 10 wt%, although both TS and EAB decreased for the films with 15 wt% AV, indicating that high AV contents would hinder intermolecular interactions among the formulation components. Maillard reaction occurred between chitosan and citric acid at the processing temperature used (115 °C), while physical interactions took place with AV, as shown by FTIR analysis. All films were insoluble but displayed hydration and limited swelling due to both physical and chemical interactions promoted by AV and citric acid, respectively. A slow AV release, governed by a Fickian diffusion controlled mechanism, and an increase of surface hydrophilicity, which favors cell adhesion, were observed. This research was funded by MCIU/AEI/FEDER, UE (RTI2018-097100-B-C22). Iratxe Zarandona thanks the Quality and Food Industry Department of the Basque Government for her fellowship (22-2018-00078)

Chitosan-pectin films with iron oxide (Fe

The increasing necessity of developing new devices for biomedical applications has added a growing social need of being environmentally respectful. In this work, we have shown that natural by-products from the food industry (soy protein and β-chitin) can be an excellent source of biomaterials to produce 3D scaffolds through simpler and cleaner processes. With the mixture of these two polymers, we have developed sponge-like scaffolds (SLS) with great physicochemical properties. Furthermore, a dialysis pre-conditioning step was enough to obtain negligible cytotoxicity in vitro. The predominant M2 macrophage profile, an elevated deposition of collagen fibres and the enhanced neovascularization capacity suggested excellent biocompatibility also in vivo. Moreover, these SLS were able to promote cell adhesion, proliferation and high loading capacity. Finally, h-MSCs 3D-cultured in these SLS released four times higher VEGF than h-MSCs seeded onto 2D plates. The green thinking strategy, properties and biocompatibility of this SLS highlight its potential as a cell delivery system for biomedical applications.

To achieve sustainability in the wine industry, by-products from winery operations are being diverted from waste streams and turned into beneficial use. Grape seed tannin (SeedT) and skin tannin (SkinT) extracts were used to modify the properties of gelatin films, and to prepare active/intelligent films. The SeedT extract showed a higher phenolic content (similar to 440 mg gallic acid (GA)/g extract) and antioxidant inhibition (similar to 20 %) than the SkinT extract (14 mg GA/g extract, 2 % antioxidant inhibition), while both extracts presented colour variations with an increase of solution pH. The addition of extracts into the gelatin formulation resulted in coloured and transparent films with lower wettability (water contact angle increased up to 92 degrees) and higher UV-light absorbance (secondary antioxidant function) properties. The films were capable of releasing tannins by up to 20 % which led to antioxidant inhibition values of up to 13 % (primary antioxidant function). The addition of SkinT tannins into the films provided the films with a pH indicator ability (intelligent function). The authors would like to thank the State Research Agency of Spain within the Juan de la Cierva - Incorporation action (IJC2019-039697I) and the Ministry of Business, Innovation and Employment (MBIE, Biocide Toolbox programme).

Indirect 3D printing combined with freeze-drying technology is proposed here as a promising method for the preparation of gelatin-based products. The addition of ribose into gelatin formulations (2.5, 3.5 and 5.0 w/v %) and subsequent heating processes at 70 and 90 °C promoted Maillard reaction with the aim of minimizing samples' moisture sensitivity. The effect of initial gelatin content and crosslinking extension on gelatin products' properties was studied by Scanning Electron Microscopy (SEM) as well as swelling and mass loss testing in different physiological and food simulants. Samples with the highest gelatin content (5.0 w/v %) and heated at 90 °C showed the highest crosslinking extension, no shape loss and the lowest mass loss percentage after 7 days of immersion in fatty food simulant and so, these samples were used as carriers for gallic acid (GA). An initial (8 h) fast release of GA, along with a subsequent slow release up to 10 days, illustrates the suitability of these products for food related applications.

Rheological properties of gelatin-based solutions containing different concentrations of ribose and/or glycerol were assessed before electrospun mats were manufactured and their properties investigated. Characterization included morphology, X-ray diffraction, Fourier transform infrared, solubility, swelling, the release of Maillard reaction (MR) products and their antioxidant activity. Gelatin concentrations >= 16 % w/v favoured the formation of smooth nanofibres in the electrospinning process due to their higher viscosity than for gelatin concentrations

In the present work, fish gelatin was employed to develop renewable and biodegradable materials, reducing environmental problems associated with conventional petroleum-based materials. Glycerol was used as plasticizer and gallic acid was added in order to enhance the functional properties of the material. L-fuzzy concept analysis was applied for modelling the formulations and properties of the films. These new methodology is used in the design of the material avoiding the traditional inefficient trial an error approach usually employed. Two applications of the developed bio-based material were analyzed: fatty food packaging application in food area and wound healing in the biomedical field. The functional properties requirements of water contact angle (CA), water vapour transmission rate (WVTR), colour L * and b * values, tensile strength (TS), elongation at break (EB) and gloss values were specified for both applications. Applying the proposed algorithm, the required formulations were estimated and the experimental results showed a high accordance with the predicted values of the final properties, as well as with the requirements. This analysis allowed finding the required formulations in a highly cost-effective way The authors thank the research groups from the Basque Gov-ernment (IT1256-19) and the University of the Basque Country UPV/EHU (GIU18/154) . This work was financially supported by the Basque Government (KK2019/00006) . Document

Native collagen doughs were processed using a syringe-based extrusion 3D printer to obtain collagen scaffolds. Before processing, the rheological properties of the doughs were analyzed to determine the optimal 3D printing conditions. Samples showed a high shear-thinning behavior, reported beneficial in the 3D printing process. In addition, tetrahydrocurcumin (THC) was incorporated into the dough formulation and its effect on collagen structure, as well as the resulting scaffold’s suitability for wound healing applications, were assessed. The denaturation peak observed by differential scanning calorimetry (DSC), along with the images of the scaffolds’ surfaces assessed using scanning electron microscopy (SEM), showed that the fibrillar structure of collagen was maintained. These outcomes were correlated with X-ray diffraction (XRD) results, which showed an increase of the lateral packaging of collagen chains was observed in the samples with a THC content up to 4%, while a higher content of THC considerably decreased the structural order of collagen. Furthermore, physical interactions between collagen and THC molecules were observed using Fourier transform infrared (FTIR) spectroscopy. Additionally, all samples showed swelling and a controlled release of THC. These results along with the mucoadhesive properties of collagen suggested the potential of these THC–collagen scaffolds as sustained THC delivery systems. This research was funded by MCI/AEI/FEDER, UE (RTI2018-097100-B-C22) and Provincial Council of Gipuzkoa.

Blend films from chicken protein isolate (CPI) and fish skin gelatin (FSG) at various CPI/FSG ratios (100:0, 80:20, 70:30, 60:40, 0:100), prepared at pH 3 or 11 were characterized. At the same pH, tensile strength (TS) of CPI/FSG films was higher than CPI and FSG films, and CPI/FSG film (60:40) had highest TS. Moreover, elongation at break (EAB) of blend films increased as FSG content augmented. EAB of CPI film and CPI/FSG (80:20) film was similar for both pHs. CPI films generally possessed higher water vapor permeability (WVP), light barrier property and b*-value than FSG counterpart. CPI films prepared at both pHs were not sealable. Nevertheless, addition of FSG improved sealing ability of blend films. At the same CPI/FSG ratio, seal strength and seal efficiency were lower for films prepared at pH 11. Moreover, higher TS and b*-value were gained, compared to those of films prepared at pH 3. Less cracks on surface and cross-section appeared for CPI/FSG films as revealed by scanning electron microscopy images, compared to CPI and FSG films. Therefore, incorporation of FSG up to 40% into blend film was able to improve mechanical properties, WVP, and sealing ability of blend films.

Extrusion bioprinting based on the development of novel bioinks offers the possibility of manufacturing clinically useful tools for wound management. In this study, we show the rheological properties and printability outcomes of two advanced dressings based on platelet-rich plasma (PRP) and platelet-poor plasma (PPP) blended with alginate and loaded with dermal fibroblasts. Measurements taken at 1 h, 4 days, and 18 days showed that both the PRP- and PPP-based dressings retain plasma and platelet proteins, which led to the upregulation of angiogenic and immunomodulatory proteins by embedded fibroblasts (e.g., an up to 69-fold increase in vascular endothelial growth factor (VEGF), an up to 188-fold increase in monocyte chemotactic protein 1 (MCP-1), and an up to 456-fold increase in hepatocyte growth factor (HGF) 18 days after printing). Conditioned media harvested from both PRP and PPP constructs stimulated the proliferation of human umbilical vein endothelial cells (HUVECs), whereas only those from PRP dressings stimulated HUVEC migration, which correlated with the VEGF/MCP-1 and VEGF/HGF ratios. Similarly, the advanced dressings increased the level of interleukin-8 and led to a four-fold change in the level of extracellular matrix protein 1. These findings suggest that careful selection of plasma formulations to fabricate wound dressings can enable regulation of the molecular composition of the microenvironment, as well as paracrine interactions, thereby improving the clinical potential of dressings and providing the possibility to tailor each composition to specific wound types and healing stages. This work was fully supported by a collaborative fundamental research grant from the Basque Government Elkartek program under grant nº. B4H KK-2019-0006-BC.

The use of biocompatible and biodegradable materials, along with promising advanced manufacturing techniques, is the new trend for biomaterials development. In this study, gelatin scaffolds loaded with dexamethasone sodium phosphate (DSP) and crosslinked with lactose were fabricated by 3D printing. The viscosity of the gelatin solution was adequate to control the shape of the printed structures where reproducible scaffolds were obtained. The post-printing crosslinking reaction between gelatin and lactose was promoted by heat-treatment and assessed by color change, Fourier transform infrared (FTIR) spectroscopy, buffer absorption capacity and solubilisation tests. Although the addition of DSP slightly affected the crosslinking extension, the reaction notably improved scaffolds’ water resistance by decreasing buffer absorption capacity values from ∼515% to 360%, as well as slowing down the solubilisation time and percentage from 45 min with 75% of solubilisation to more than 7 days with 55% of solubilisation. The fast release of DSP under physiological conditions along with the surface characteristics of scaffolds demonstrated the possibility of using these scaffolds for targeted drug release.

The properties of monolayer and bilayer fish gelatin films and the corresponding films containing epigallocatechin gallate (EGCG) were examined. Bilayer films showed higher tensile strength, water vapor and light barrier properties but also higher opaqueness and yellowness than monolayer films. No differences in elongation at break and oxygen barrier property between monolayer and bilayer films were observed. Those films were used to produce pouches, in which chicken skin oil (CSO) was packaged. CSO packaged in the pouches prepared with the films containing EGCG showed lower peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and volatile compounds after 30 days of storage in comparison with that packaged in low-density polyethylene (LDPE) pouch. Additionally, at the end of the storage, linoleic acid (C18:2 n-6) and linolenic acid (C18:3 n-9) were more retained in CSO packaged in the pouches made from the films containing EGCG. Therefore, monolayer or bilayer gelatin films incorporated with EGCG could be used as packaging for oils prone to lipid oxidation.

Soy protein isolate (SPI) and hydrolyzed keratin (HK) were employed to develop compression molded films. In contrast to other studies, in which toxic chemicals or expensive methods are usually employed to hydrolyze feather keratin, in this research a novel approach was addressed. A solution of NaOH (1 M) was employed and the use of high temperatures was avoided during the process in order to obtain a simple, environmentally friendly and inexpensive method to hydrolyze feather keratin, which can be used for the development of thermoplastic films. In addition to the valorization of agro-industrial waste, the main aim of the incorporation of hydrolyzed feather keratin into film forming formulations was to increase the sulfur content and, thus, the ability to form disulphide bonds, improving the chemical and thermal stability of the resulting films.

Wool, choline dihydrogen phosphate ([Ch][DHP]) or choline serinate ([Ch][Seri) ionic liquids (ILs) were incorporated into native collagen formulations and films were prepared by compression molding. Scanning electron microscopy (SEM) images showed no agglomeration, indicating good dispersion of additives within films. The denaturation peak observed by differential scanning calorimetry (DSC), along with infrared spectroscopy (FTIR) results, showed that collagen fibrillary structure was preserved in all samples. These outcomes were correlated with X-ray diffraction (XRD) patterns. Wool or ILs addition increased tensile strength and improved electrical conductivity and all films showed antistatic behaviour. The samples showed a high dielectric constant, mainly determined by mobile charge contributions. This work shows the potential of native collagen films with tuneable physical-chemical characteristics for a new generation of sustainable materials for a wide variety of applications., This research was funded by MCI/AEI/FEDER, UE, grant number RTI2018-097100-B-C22. This work was also supported by the Portuguese Foundation for Science and Technology (FCT) under strategic funding UIDB/04650/2020, UID/FIS/04650/2021, project PTDC/FIS-MAC/28157/2017, grant SFRH/BPD/121526/2016 (D.M.C) and Investigator FCT Contract 2020.04028.CEECIND (C.M.C.) funded by national funds through FCT and by the ERDF through the COMPETE2020-Programa Operacional Competitividade e Internacionalização (POCI). The authors also acknowledge funding from the Basque Government (KK-2021/00131). Mireia Andonegi also thanks the Basque Government for her fellowship (PRE_2017_1_0025). Thanks are also due to the Advanced Research Facilities (SGIker) from the UPV/EHU. Finally, the authors would like to thank Paula Menoyo for the wool provided.

In this study, a response surface methodology (RSM) using a Box-Behnken design was applied to optimize the mechanical response (tensile strength, elongation at break and Young's modulus) of fish gelatin films. These responses were analyzed as a function of glycerol content (0-10% on gelatin basis), added as a plasticizer, gallic acid content (5-15% on gelatin basis), used as crosslinker, and solution pH (4.5-10). Second order polynomial models were adjusted for the three responses, and they were found to be reliable according to the standard statistical analysis. The values of the independent factors that maximize the responses were also determined. In order to relate mechanical performance to material structure, Fourier transform infrared (FTIR) analysis was carried out and this revealed that a reaction occurs between gelatin and gallic acid through a process that releases water and provides a plasticizing effect. The performed time-, material- and cost-saving optimization of the formulation based on biodegradable compounds from abundant renewable resources enabled a sustainable approach to the development of new materials.

Bioactive compounds from natural resources have been pointed out as promising substances with great benefits for human health. Furthermore, new techniques for their extraction have been reviewed in order to consider a global approach taking economic and environmental issues into account. Additionally, the incorporation of these biologically active compounds into protein-based products manufactured via different processing methods, such as solution casting, compression moulding, electrospinning, freeze-drying, and 3D printing, has been assessed, since the design and manufacturing method employed have a direct influence into the final properties of the material. Hence, new opportunities to develop active biopolymeric materials with great potential in food and biomedical applications have been presented. This review aims to provide an overview of some advanced technologies employed for bioactive extraction, as well as the bioactives incorporation into protein formulations to produce biomaterials and food packaging.

The efficient use of biomass is one of the overarching objectives within sustainable development. In this context, fish gelatin and anthocyanins derived from food processing waste were used to prepare bio-based films. Anthocyanins were extracted by a simple and sustainable process and characterized before analyzing their antioxidant activity as a function of pH, in order to select the film processing conditions. In this regard, it is worth mentioning that a more sustainable process than the conventional solution casting was used in the preparation of films, since compression molding is a more rapid and less energy-consuming process. Furthermore, anthocyanins incorporated into film forming formulations maintained their antioxidant activity, as shown by the radical scavenging capacity. Additionally, the incorporation of anthocyanins decreased the water sensitivity of films, maintaining mechanical properties and, thus, highlighting the potential of these films as active packaging.

The vision impairments suffered by millions of people worldwide and the shortage of corneal donors show the need of substitutes that mimic native tissue to promote cell growth and subsequent tissue regeneration. The current study focused on the in vitro assessment of protein-based biomaterials that could be a potential source for corneal scaffolds. Collagen, soy protein isolate (SPI), and gelatin films cross-linked with lactose or citric acid were prepared and physicochemical, transmittance, and degradation measurements were carried out. In vitro cytotoxicity, cell adhesion, and migration studies were performed with human corneal epithelial (HCE) cells and 3T3 fibroblasts for the films’ cytocompatibility assessment. Transmittance values met the cornea’s needs, and the degradation profile revealed a progressive biomaterials’ decomposition in enzymatic and hydrolytic assays. Cell viability at 72 h was above 70% when exposed to SPI and gelatin films. Live/dead assays and scanning electron microscopy (SEM) analysis demonstrated the adhesion of both cell types to the films, with a similar arrangement to that observed in controls. Besides, both cell lines were able to proliferate and migrate over the films. Without ruling out any material, the appropriate optical and biological properties shown by lactose-crosslinked gelatin film highlight its potential for corneal bioengineering. This research study was supported by grants from the Department of Heath of the Basque Government (RIS3, 2019222049), the University of the Basque Country UPV/EHU-Instituto Clinico Quirurgico de Oftalmologia ICQO (US19/18), and MCI/AEI/FEDER, UE (grant number RTI2018-097100-B-C22). C.R.-V. was supported by a fellowship from the University of the Basque Country UPV/EHU.

The use of L-fuzzy concept analysis for the determination of the formulations of gelatin-based films that fulfillspecifc functional properties is reported. The requirements of water contact angle (CA), water vapourtransmission rate (WVTR), L* and b* colour values, tensile strength (TS), elongation at break (EB) and glossvalues were specified for both fatty food packaging and wound healing applications. Once the requiredformulations were estimated by L-fuzzy concepts, the experimental results showed a high accordance with thepredicted values of the nal properties, as well as with the requirements. The errors were lower than 20% in allcases, except in colour (for food packaging) and gloss and elongation at break (for wound healing), in whichthe nal properties were even better that the estimations. This analysis allowed nding the requiredformulations in a highly cost-effective way.

Two exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) strains, Liquorilactobacillus (L.) sp CUPV281 and Liquorilactobacillus (L.) mali CUPV271, were isolated from Spanish apple must. Each of the strains produced a dextran, with different branching degrees, to be incorporated into soy protein isolate (SPI) film-forming formulations. Films were prepared by compression molding, a more rapid processing method than solution casting and, thus, with a greater potential for scaling-up production. Thermal analysis showed that SPI and EPS start the degradation process at temperatures above 190 &deg, C, confirming that the compression temperature selected (120 &deg, C) was well below the corresponding degradation temperatures. Resulting films were transparent and homogeneous, as shown by UV-Vis spectroscopy and SEM, indicating the good compatibility between SPI and EPS. Furthermore, FTIR analysis showed that the interactions between SPI and EPS were physical interactions, probably by hydrogen bonding among the polar groups of SPI and EPS. Regarding antifungal/fungistatic activity, LAB strains used in this study showed an inhibitory effect on germination of fungal spores.

Native collagen scaffolds were prepared in this work, in which both materials and environmental approaches were considered with the aim of providing a global strategy towards more sustainable biomaterials. From the environmental perspective, it is worth mentioning that acid and enzymatic treatments have been avoided to extract collagen, allowing the reduction in the use of resources, in terms of chemicals, energy, and time, and leading to a low environmental load of this step in all the impact categories under analysis. With the incorporation of chitosan into the scaffold-forming formulations, physical interactions occurred between collagen and chitosan, but the native collagen structure was preserved, as observed by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analyses. The incorporation of chitosan also led to more homogenous porous microstructures, with higher elastic moduli and compression resistance for both dry and hydrated scaffolds. Furthermore, hydrated scaffolds preserved their size and shape after some compression cycles. This research was funded by the Ministry of Science, Innovation and Universities (RTI2018-097100-B-C22) and the Basque Government (38-2018-00037). M.A. (PRE_2017_1_0025) and A.Ir. (PRE_2019_1_0031) thank the Basque Government for their fellowships.