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Bacterial cellulose nanofiber (BCNF) with high thermal stability produced by an ecofriendly process has emerged as a promising solution to realize safe and sustainable materials in the large-scale battery. However, an understanding of the actual thermal behavior of the BCNF in the full-cell battery has been lacking, and the yield is still limited for commercialization. Here, we report the entire process of BCNF production and battery manufacture. We systematically constructed a strain with the highest yield (31.5%) by increasing metabolic flux and improved safety by introducing a Lewis base to overcome thermochemical degradation in the battery. This report will open ways of exploiting the BCNF as a "single-layer"separator, a good alternative to the existing chemical-derived one, and thus can greatly contribute to solving the environmental and safety issues. [ABSTRACT FROM AUTHOR]

We carried out the first simulation on multi-stage continuous high cell density culture (MSC-HCDC) to show that the MSC-HCDC can achieve batch/fed-batch product titer with much higher productivity to the fed-batch productivity using published fermentation kinetics of lactic acid, penicillin and ethanol. The system under consideration consists of n-serially connected continuous stirred-tank reactors (CSTRs) with either hollow fiber cell recycling or cell immobilization for high cell-density culture. In each CSTR substrate supply and product removal are possible. Penicillin production is severely limited by glucose metabolite repression that requires multi-CSTR glucose feeding. An 8-stage C-HCDC lactic acid fermentation resulted in 212.9 g/L of titer and 10.6 g/L/h of productivity, corresponding to 101 and 429% of the comparable lactic acid fed-batch, respectively. The penicillin production model predicted 149% (0.085 g/L/h) of productivity in 8-stage C-HCDC with 40 g/L of cell density and 289% of productivity (0.165 g/L/h) in 7-stage C-HCDC with 60 g/L of cell density compared with referring batch cultivations. A 2-stage C-HCDC ethanol experimental run showed 107% titer and 257% productivity of the batch system having 88.8 g/L of titer and 3.7 g/L/h of productivity. MSC-HCDC can give much higher productivity than batch/fed-batch system, and yield a several percentage higher titer as well. The productivity ratio of MSC-HCDC over batch/fed-batch system is given as a multiplication of system dilution rate of MSC-HCDC and cycle time of batch/fed-batch system. We suggest MSC-HCDC as a new production platform for various fermentation products including monoclonal antibody. [ABSTRACT FROM AUTHOR]

Extracellular proteins of filamentous fungi are important for biomedical and biotechnological applications. Aspergillus terreus not only comprises an important class of organisms that have significant commercial relevance to the biotechnology industry, but also is an emerging fungal pathogen. However, no information is available on the extracellular proteome of A. terreus. Thus, we analyzed the extracellular proteomes of A. terreus under different culture conditions using sucrose, glucose, or starch as a main carbon source. A total of 82 protein spots including 39 unique proteins was successfully identified by 2-DE and nano-LC-MS/MS. Of these, 12 proteins were detected in the presence of at least two different carbon sources, whereas 16 proteins were unique to sucrose-, 3 to glucose-, and 8 to starch-grown A. terreus. Most of the proteins with known functions are hydrolytic enzymes, such as hydrolases, glycosylases and proteases, some of which include potential allergens. Both oryzin and a predicted protein (ATEG_07481) were the most abundant in all three media. Particularly, oryzin was highly secreted in high concentration sucrose medium. These proteomic data will be useful for studying protein secretion in further detail, and finding fusion partners for the extracellular production of homologous or heterologous proteins in A. terreus. [ABSTRACT FROM AUTHOR]