The extractive desulfurization of thiophene (TS), dibenzothiophene (DBT), and benzothiophene (BT) in model oil was carried out using carboxylic acid-based deep eutectic solvents (DES). It was found that DES formed by formic acid as hydrogen bond donor and Tetrabutylammonium bromide (TBAB) as hydrogen bond acceptor could efficiently separate organosulfur from oils. The influence parameters in this process were discussed, such as extraction temperature, reaction time, mass ratio of DES to oil; multistage extraction effect; recycle times and regeneration of DES. The results showed that the desulfurization selectivity of TBAB/HCOOH followed the order TS < BT ≈DBT. Under the Optimized conditions, the sulfur removal of BT, DBT and TS were 81.75%, 80.47% and 72% in a single stage, respectively, and after three cycles, it will rise to 98.32%, 98.24% and 97.6%. The sulfur content in fuels can be achieved to less than 8.4, 8.8 and 12 ppm for BT, DBT and TS. In addition, by mechanism discussion, it was proved that hydrogen bonding between the sulfide and DES was the main driving force of the extraction desulfurization process.

For thousands of years, sanghuang is distinctive as a general designation for a group of precious and rare Chinese medicinal mushrooms. Numerous investigations have revealed that polysaccharide is one of the important biological active ingredients of sanghuang with various excellent biological activities, including antioxidant, anti-aging, anti-tumor, immunomodulatory, anti-inflammatory, anti-diabetic, hepatoprotective, and anti-microbial functionalities. For the past two decades, preparation, structural characterization, and reliable bioactivities of the polysaccharides from fruiting bodies, cultured mycelia, and fermentation broth of sanghuang have been arousing extensive interest, and particularly, different strains, sources, and isolation protocols might result in obvious discrepancies in structural features and bioactivities. Therefore, this review summarizes the recent reports on preparation strategies, structural features, bioactivities, and structure-activity relationships of sanghuang polysaccharides, which will enrich the knowledge on the values of natural sanghuang polysaccharides and support their further development and utilization as therapeutic agents, vaccines, and functional foods in tonic and clinical treatment.

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Extra-cellular polymeric substances (EPS) are a major cause of membrane fouling in membrane bioreactors (MBRs). In this study, an anoxic–oxic membrane bioreactor (A/O-MBR) was run continuously for 98 days. The runs were divided into three stages according to hydraulic retention time (HRT) (11.8, 12.5 and 14.3 h, respectively). EPS were extracted from the reactor under the different HRTs. A quartz crystal microbalance with dissipation monitoring (QCM-D) and Fourier transform infrared (FT–IR) were used to study the adherence layer structures and the adsorption behaviours of EPS on the membrane surface. The results indicated that the removal rate of TN was more susceptible to HRT than NH3-N. The observations in the QCM-D suggested that at the lowest HRT (11.8 h), the structure of the adsorption layer is loose and soft and the fluidity was better than for HRTs of 12.5 or 14.3 h. It is likely one of the major reasons for the rapidly blocking of the membrane pores. Furthermore, the higher EPS adherence as analyzed in the QCM-D and EPS concentration could induce a higher osmotic pressure effect, leading to a rapid membrane-fouling rate.

Increasing demand for recombinant proteins necessitates efficient protein production processes. In this study, a continuous process for human epidermal growth factor (hEGF) secretion by Escherichia coli was developed by taking advantage of biofilm formation. Genes bcsB, fimH, and csgAcsgB that have proved to facilitate biofilm formation and some genes moaE, yceA, ychJ, and gshB potentially involved in biofilm formation were examined for their effects on hEGF secretion as well as biofilm formation. Finally, biofilm-based fermentation processes were established, which demonstrated the feasibility of continuous production of hEGF with improved efficiency. The best result was obtained from ychJ-disruption that showed a 28% increase in hEGF secretion over the BL21(DE3) wild strain, from 24 to 32 mg/L. Overexpression of bcsB also showed great potential in continuous immobilized fermentation. Overall, the biofilm engineering here represents an effective strategy to improve hEGF production and can be adapted to produce more recombinant proteins in future.

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