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Micropatterned pores in scaffolds have been extensively used to promote mass transport, tissue integration, and vascularization. However, the combined effects of microchannels and biomimetic structure on cell functions have not been investigated. Herein, microchannels with varying diameters of about 100, 200, and 400 $\mu$m were fabricated in the scaffolds composed of nanofibrous (diameter\thinspace, This work was supported by the National Natural Science Foundation of China (Grant Nos. 31870963 and 51973058), the Key Research and Development Program of Jiangxi Province (No. 20192ACB80008), and the Key Project of Natural Science Foundation of Jiangxi Province (20202ACBL204013), info:eu-repo/semantics/publishedVersion

Bacterial cellulose (BC), obtained by fermentation, is an innovative and promising material with a broad spectrum of potential applications. Despite the increasing efforts towards its industrialization, a deeper understanding of the environmental impact related to the BC production process is still required. This work aimed at quantifying the environmental, health, and resource depletion impacts related to a production of BC. An attributional life cycle assessment (LCA) was applied to a process design of production of BC, by static culture, following a cradle-to-gate approach. The LCA was modeled with GaBi Pro Software using the ReCiPe 2016 (H) methodology with environmental impact indicators at midpoint level. The functional unit was defined as 1 kg of BC (dry mass), in 138.8 kg of water. From the total used resources (38.9 ton/kg of BC), water is the main one (36.1 ton/kg of BC), most of which (98%) is returned to fresh waters after treatment. The production of raw materials consumed 17.8 ton of water/kg of BC, 13.8 ton/kg of BC of which was for the production of carton packaging, culture medium raw materials, and sodium hydroxide (for the washing of BC). The remaining consumed water was mainly for the fermentation (3.9 ton/kg) and downstream process (7.7 ton/kg). From the identified potential environmental impacts, the production of raw materials had the highest impact, mainly on “Climate change”, “Fossil depletion”, “Human toxicity, non-cancer”, and “Terrestrial toxicity”. The sodium dihydrogen phosphate production, used in the culture medium, showed the highest environmental impacts in “Human toxicity, non-cancer” and “Terrestrial ecotoxicity”, followed by corn syrup and carton production. The static culture fermentation and downstream process showed impact in “Climate change” and “Fossil depletion”. Per se, the BC production process had a small contribution to the consumption of resources and environmental impact of the BC global life cycle.

Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10570-020-03078-w) contains supplementary material, which is available to authorized users., The impact of graphene oxide (GO) on normal cells has been widely investigated. However, much less is known on its effect on cancer cells. Herein, GO nanosheets were incorporated into electrospun cellulose acetate (CA) microfibers. The GO-incorporated CA (GO/CA) microfibers were combined with bacterial cellulose (BC) nanofibers via in situ biosynthesis to obtain the nano-microfibrous scaffolds. The GO/CA-BC scaffolds were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The GO/CA-BC scaffolds were used for breast cancer cell culture to evaluate the effect of GO on cancer cell behavior. Fluorescence images revealed large multicellular clusters on the surface of GO/CA-BC scaffolds. Compared to the bare CA-BC scaffold, the GO/CA-BC scaffolds not only showed enhanced mechanical properties but also improved cell proliferation. It is expected that the GO/CA-BC scaffolds would provide a suitable microenvironment for the culture of cancer cells which is necessary for drug screening and cell biology study., This work was supported by National Natural Science Foundation of China (Grant nos. 51572187, 51973058, 31660264, 31870963), the Key Research and Development Program of Jiangxi Province (No. 20192ACB80008), and the Youth Science Foundation of Jiangxi Province (No. 20181BAB216010), and Key Project of Natural Science Foundation of Jiangxi Province (No. 20161ACB20018)., info:eu-repo/semantics/publishedVersion

In this work, biocompatibility of bacterial cellulose (BC) was assessed as the scaffold for corneal stroma replacement. Biocompatibility was evaluated by examining rabbit corneal epithelial and stromal cells cultured on the BC scaffold. The growth of primary cells was assessed by optical microscope, scanning electron microscope (SEM), and transmission electron microscope (TEM). Live/dead viability/cytotoxicity assay and CCK-8 assay were used to evaluate cell survival. BC was surgically implanted in vivo into a stromal pocket. During a 3-month follow-up, the biocompatibility of BC was assessed. We found that epithelial and stromal cells grew well on BC and showed a survival rate of nearly 100\\%. The SEM examination for both kinds of cell showed abundant leafy protrusions, spherical projections, filopodia, cytoskeletons, and cellular interconnections. The stromal cells cultured on BC arranged regularly. TEM observation revealed normal cellular microstructure and a tight adhesion to the BC membrane. In vivo observation confirmed the optical transparency of BC during 3-month follow-up. The results demonstrated that BC had good biocompatibility for the tissue engineering of corneal stroma., This work is supported by the National Natural Science Foundation of China (Grant Nos. 81200663, 51572187, 51973058, and 31870963), Tianjin Clinical Key Discipline Project (Grant No. TJLCZDXKM014), and Key Research and Development Program of Jiangxi Province (No. 20192ACB80008, 20171BBG70112)., info:eu-repo/semantics/publishedVersion

On a near future, bio-based economy will assume a key role in our lives. Lignocellulosic materials (e.g., agroforestry residues, industrial/solid wastes) represent a cheaper and environmentally friendly option to fossil fuels. Indeed, following suitable processing, they can be metabolized by different microorganisms to produce a wide range of compounds currently obtained by chemical synthesis. However, due to the recalcitrant nature of these materials, they cannot be directly used by microorganisms, the conversion of polysaccharides into simpler sugars being thus required. This conversion, which is usually undertaken enzymatically, represents a significant part on the final cost of the process. This fact has driven intense efforts on the reduction of the enzyme cost following different strategies. Here, we describe the fundamentals of the enzyme recycling technology, more specifically, cellulase recycling. We focus on the main strategies available for the recovery of both the liquid- and solid-bound enzyme fractions and discuss the relevant operational parameters (e.g., composition, temperature, additives, and pH). Although the efforts from the industry and enzyme suppliers are primarily oriented toward the development of enzyme cocktails able to quickly and effectively process biomass, it seems clear by now that enzyme recycling is technically possible., Financial support from FEDER and Fundação para a Ciência e a Tecnologia (FCT): GlycoCBMs Project PTDC/AGR-FOR/3090/2012–FCOMP-01-0124- FEDER-027948 and Strategic Project PEst-OE/EQB/LA0023/2013, Project BBioInd-Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028 Cofunded by the Programa Operacional Regional do Norte (ON.2–O Novo Norte), QREN, FEDER and the PhD grant to DG (SFRH/BD/88623/ 2012) and ACR (SFRH/BD/89547/2012).

A novel hydrogel was obtained by reticulation of chitosan with dextrin enzymatically linked to vinyl acrylate (dextrin-VA), without cross-linking agents. The hydrogel had a solid-like behaviour with G' (storage modulus) >> G'' (loss modulus). Glucose diffusion coefficients of 3.9 x 10(-6) +/- 1.3 x 10(-6) cm(2)/s and 2.9 x 10(-6) +/- 0.5 x 10(-6) cm(2)/s were obtained for different substitution degrees of the dextrin-VA (20% and 70% respectively). SEM observation revealed a porous structure, with pores ranging from 50 microm to 150 microm.