Recombinant Escherichia coli XL1-Blue harboring a high-copy-number plasmid containing the Alcaligenes eutrophus polyhydroxyalkanoate synthesis genes could efficiently synthesize poly(3-hydroxybutyrate) (PHB) in a complex medium containing yeast extract and tryptone but not in a defined medium. One of the reasons for the reduced PHB production in a defined medium was thought to be severe filamen...

BACKGROUND Fungal morphology and aeration play a significant role in the growth process of Mortierella alpina. The production of microbial oil rich in arachidonic acid (ARA) in M. alpina was enhanced by using a multi-stage fermentation strategy which combined fed-batch culture with precise control of aeration and agitation rates at proper times. RESULTS The fermentation period was divided int...

[This corrects the article DOI: 10.1186/s13068-016-0466-5.].

Apple pomace extract (APE) in aerobic variable fed batch culture under standardized fermentation parameters was evaluated for the production of baker’s yeast. The substrate was fed at a flow rate of 0.39 dm h to regulate fermentable sugar concentration between 1-2 % in bioreactor. An average specific growth rate of 0.24 h and cellular yield coefficient of 0.48 g/g sugar was obtained during bake...

Although serum-free media have been widely used in mammalian cell culture for therapeutic protein production, the effects of serum-substitutes on product quality have not been extensively examined. This study observed an adverse effect of Primatone RL, an animal tissue hydrolysate commonly used as a serum-substitute to promote cell growth, on sialylation of interferon-gamma (IFN-gamma) derived ...

Vero cells were grown adherent to microcarriers (Cytodex 1; 3 g L(-1)) using animal component free media in stirred-tank type bioreactors. Different strategies for media refreshment, daily media replacement (semi-batch), continuous media replacement (perfusion) and recirculation of media, were compared with batch cultivation. Cell densities increased using a feed strategy from 1×10(6) cells mL(...

Clavulanic acid (CA) is a potent inhibitor of β-lactamases, enzymes that are responsible for the hydrolysis of β-lactam antibiotics. It is a secondary metabolite produced by the filamentous aerobic bacterium Streptomyces clavuligerus in submerged cultivations. In the present work clavulanic acid production in batch, fed-batch and continuous bioreactors was studied with the objective of increasi...

Several important properties of poly(3-hydroxybutyric-co-3-hydroxyvaleric acids) (P(3HB-co-3HV) depend mainly on the HV unit fraction of the copolymer. Sequential and simultaneous feeding of glucose and valerate were employed to produce P(3HB-co-3HV) in a fed-batch culture of Ralstonia eutropha, and the effects of feeding models on the cell growth, 3HV unit fraction, and copolymer productivity ...

Alcaligenes latus has been known to produce poly(3-hydroxybutyrate) (PHB) in a growth-associated manner even under nutrient-sufficient conditions. However, the PHB content obtained by fed-batch culture was always low, at ca. 50%, which makes the recovery process inefficient. In this study, the effect of applying nitrogen limitation on the production of PHB by A. latus was examined. In flask and...

Cordycepin (3′-deoxyadenosine) exhibits antimicrobial, anticancer, antimetastatic, immunomodulatory and insecticidal effects, and is one of the most important bioactive anticancer agents found in Cordyceps species (summer grass-winter worm). However, due to the requirements of specific hosts and strict growth environments, Cordyceps militaris is very scarce in nature. Therefore, the production ...