Sodium cellulose sulfate (NaCS)/Ploy-dimethyl-dially-ammonium-chloride (PDMDAAC) microcapsules were used as a novel pseudo "Cell Factory" to immobilize mixed bacteria for hydrogen production under anaerobic conditions. Compared to free cells, the hydrogen production was increased more than 30% with NaCS/PDMDAAC microcapsules as the pseudo "Cell Factory". The biomass was increased from 1.5 g/L in free cell culture to 3.2 g/L in the pseudo "Cell Factory". This pseudo "Cell Factory" system showed the excellent stability during 15 repeated-batches. The hydrogen yield maintained 1.73-1.81 mol H2/mol glucose. The fermentation cycle was shortened from 48 h to 24 h, resulting in an increase of 198.6% in the hydrogen production rate. There were high percentage of butyric acid and acetic acid in the culture broth, which meant that the pseudo "Cell Factory" established in the present work could be used for the multi-product system.
Bacteria ; classification ; genetics ; metabolism ; Capsules ; Cells, Immobilized ; metabolism ; Cellulose ; analogs & derivatives ; chemistry ; Fermentation ; Hydrogen ; metabolism ; Polyethylenes ; chemistry ; Quaternary Ammonium Compounds ; chemistry

We studied the ability of lpdA gene knockout Escherichia coli to ferment different sugars in mineral salts medium for the production of pyruvate. The sugars studied were glucose, fructose, xylose and mannose at a concentration of 10 g/L. At the same time, effect of inoculum size on lpdA fermentation with glucose was studied. The strain was able to use all sugars for biomass generation and pyruvate production. The lpdA knockout mutant converted glucose, fructose, xylose and mannose to pyruvate with yields of 0.884 g/g, 0.802 g/g, 0.817 g/g and 0.808 g/L, respectively. The pyruvate accumulation curve coupled with cell growth except for mannose as carbon source. When the inoculation size increased, the rate of glucose consumption, pyruvate accumulation and cell growth increased but lower pyruvate concentration. This study demonstrates that E. coli lpdA mutant has the potential to produce pyruvic acid from xylose and mannose.
Carbon ; metabolism ; Dihydrolipoamide Dehydrogenase ; genetics ; Escherichia coli ; genetics ; metabolism ; Escherichia coli Proteins ; genetics ; Fermentation ; Fructose ; metabolism ; Gene Knockout Techniques ; Glucose ; metabolism ; Mannose ; metabolism ; Pyruvic Acid ; metabolism ; Xylose ; metabolism

OBJECTIVE： To investigate the potential pharmacological mechanism of the seed of Draba nemorosa， and to provide reference for further development， utilization and clinical application. METHODS： Effective components and related target proteins of D. nemorosa were screened and identified by using TCMSP and STRING database. Cytoscape 3.7.0 software was used to construct a visual network of effective components and target proteins for the seed of D. nemorosa， and the network topology analysis was performed. The targeting protein-protein interaction （PPI） network was constructed and analyzed by STRING database and Cytoscape 3.7.0 software. KEGG pathway enrichment of target proteins was analyzed by DAVID bioinformatics resource database. RESULTS： A total of 9 effective components were screened from the seed of D. nemorosa， including quercetin， kaempferol， β-sitosterol， etc. Totally 174 target proteins were obtained， mainly including PTGS2， NCOA2， PGR， etc. Among them， JUN and MAPK1 were core proteins in PPI network. KEGG enrichment pathway included PI3K/Akt signaling pathway， TNF-α signaling pathway， HIF-1 signaling pathway， Toll-like receptor signaling pathway and thyroid hormone signal pathway， etc. CONCLUSIONS： Effective components from the seed of D. nemorosa such as quercetin， kaempferol and β-sitosterol may act on PTGS2， JUN and MAPK1 target proteins through PI3K-Akt signaling pathway and TNF-α signaling pathway， thus exert the effects of purging lung， relieving asthma， promoting edema and reducing edema.