Self-immobilized recombinant Acetobacter xylinum for biotransformation

Biotechnology and Bioprocess Engineering – From the First Ullmann's Article to Recent Trends

“…Properties like the high resistance towards unfavorable environmental conditions, which usually characterize biofilms as an undesirable habit on medical and technical equipment, e.g., on implants or heat exchangers, are of considerable advantage for their use as production systems. Additionally, the toxicity of reagents used in the artificial immobilization [34] or mechanically complicated set-ups for cell retention Figure 1. Itaconic acid fermentation of enzymatically hydrolyzed beech wood with Aspergillus terreus DSM 826 in a shake flask.…”

“…The material surface, which constitutes the substratum of the biofilm, affects not only the vitality and stability of the culture, but probably also has an impact on its productivity. Thus, the question is which material surfaces and surface structures are best for long-term stability and productivity of biofilms [31] Glycolic acid Pseudomonas diminuta Trickle bed reactor [37] Octanol Pseudomonas putida PpS81 (R) Membrane reactor [36] Pyruvate Acetobacter xylinum (R) Stirred tank reactor [34] Tryptophan synthase Escherichia coli PHL644 Shake flask [32] polymeric matrix can also be a disadvantage for mass transfer. Although the observed 3D architecture with channels and pores in mature biofilms promotes the cell supply, it also influences the stability of the system [5].…”

Microbial biofilms in biotechnological processes

“…The biocatalyst showed improved thermal and operational stability but demonstrated D amino acid oxidase activity as only 10% of the free cells' activity [49].…”

Biotechnologie und Bioverfahrenstechnik – Vom ersten Ullmanns Artikel bis hin zu aktuellen Forschungsthemen

“…Zu den drei grundlegenden Betriebsarten biotechnologischer Prozesse zählen Batch-, Fed-Batch-und kontinuierliche Verfahren. Die Toxizität der bei der künstlichen Immobilisierung verwendeten Reagenzien [34] oder auch mechanisch komplizierte Bauteile zur Zellrückhaltung [35] werden zudem gänzlich vermieden. Für biologische Prozesse nachteilig sind dabei jedoch unter anderem die vergleichsweise geringe Systemstabilität, das Kontaminations-und Mutationsrisiko sowie eine ebenfalls erforderliche kontinuierliche Aufreinigung der Produkte.…”