Macromol

Edible mushrooms are an underexplored source of industrial proteases, whose synthesis is highly dependent on the cultivation substrate. This study investigated the effect of nine culture media on the proteolytic profiles of Auricularia sp., Lentinus sp., Macrocybe sp., and Grifola frondosa. Fungi were cultivated on diverse media (e.g., Czapek, Malt, Soy Flour). We analyzed total protein, specific activities (total, cysteine, serine proteases) using a biochemical assay, and protein secondary structure via FTIR, with metabolic patterns identified by PCA. A dissociation was found between total protein yield (highest in MFI/Casein media) and specific activity (highest in maltose media), suggesting catabolite repression. Distinct metabolic strategies emerged: Grifola frondosa specialized in serine protease production in the minimal Czapek medium (catabolic derepression), while Macrocybe sp. maximized cysteine protease production on soy flour (substrate induction). FTIR confirmed this, revealing a β-sheet-dominant (75.5%) structure for Grifola extract versus a random-coil-dominant (60.8%) structure for Macrocybe. This study provides a framework for mechanism-based bioprocess design, enabling the tailored production of serine proteases from G. frondosa (Czapek medium) or cysteine proteases from Macrocybe sp. (soy medium) for customized biotechnological applications.

Optical frames are used worldwide to correct visual impairments, protect from UV damage, or simply for fashion purposes. Optical frames are often made of poorly biodegradable and fossil-based materials, with designs not targeted to everyone’s tastes and requirements. Additive manufacturing processes allow personalisation of optical frames and the use of new sustainable biomaterials to replace fossil-based ones. This comprehensive review combines an extensive survey of the scientific literature, market trends, and information from other relevant sources, analysing the biomaterials currently used in additive manufacturing and identifying biomaterials (biopolymers, natural fibres, and natural additives) with the potential to be developed into biocomposites for printing optical frames. Requirements for optical devices were carefully considered, such as standards, regulations, and demands for manufacturing materials. By comparing with fossil-based analogues and by discussing the chemical, physical, and mechanical properties of each biomaterial, it was found that combining various materials in biocomposites is promising for achieving the desirable properties for printing optical frames. The advantages of the various techniques of this cutting-edge technology were also analysed and discussed for optical industry applications. This study aims to answer the central research question: which biopolymers and biocomposite constituents (natural fibres, plasticisers, and additives) have the ideal mechanical, thermal, physical, and chemical properties for combining into a biomaterial suitable for producing sustainable, customisable, and inclusive optical frames on demand, using additive manufacturing techniques.

Poly(L-lactide-co-ε-caprolactones) (PLCL) are promising biodegradable polymers with tunable properties for various biomedical applications. Along with the composition, the microstructure of PLCL chain is an important factor affecting its properties, crystallinity, and degradation profile. In this study, to find effective ways for tailoring the microstructure of PLCL chain, kinetic patterns of L-lactide/ε-caprolactone (75:25) ring-opening copolymerization in the presence of two different catalysts were evaluated. The kinetic studies, accompanied by the assessment of the evolution of PLCL microstructure over the reaction course, provided the optimal regimes for synthesis of PLCL with a fixed composition (LA:CL = 75:25) and different chain microstructure. This was achieved by employing two types of catalysts (tin(II) 2-ethylhexanoate and zirconium(IV) acetylacetonate) and delayed co-monomer addition approach. The control of average LA block length (l_LA) was achieved in a wide range from 4 to 14 monomeric units. Differential scanning calorimetry and wide-angle X-ray scattering revealed a pronounced effect of l_LA on glass transition temperature, melting temperature, and crystallinity.