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The microbiologically influenced corrosion (MIC) resistance of a novel Cu-bearing 2205 duplex stainless steel (2205 Cu-DSS) against an aerobic marinePseudomonas aeruginosabiofilm was investigated. The electrochemical test results showed thatRpincreased andicorrdecreased sharply after long-term immersion in the inoculation medium, suggesting that 2205 Cu-DSS possessed excellent MIC resistance to theP. aeruginosabiofilm. Fluorescence microscope images showed that 2205 Cu-DSS possessed a strong antibacterial ability, and its antibacterial efficiency after one and seven days was 7.75% and 96.92%, respectively. The pit morphology comparison after 14 days between 2205 DSS and 2205 Cu-DSS demonstrated that the latter showed a considerably reduced maximum MIC pit depth compared with the former (1.44 μmvs9.50 μm). The experimental results suggest that inhibition of the biofilm was caused by the copper ions released from the 2205 Cu-DSS, leading to its effective mitigation of MIC byP. aeruginosa. [ABSTRACT FROM AUTHOR]

Today's global energy crisis requires a multifaceted solution. Bioenergy is an important part of the solution. The microbial fuel cell (MFC) technology stands out as an attractive potential technology in bioenergy. MFCs can convert energy stored in organic matter directly into bioelectricity. MFCs can also be operated in the electrolysis mode as microbial electrolysis cells to produce bioproducts such as hydrogen and ethanol. Various wastewaters containing low-grade organic carbons that are otherwise unutilized can be used as feed streams for MFCs. Despite major advances in the past decade, further improvements in MFC power output and cost reduction are needed for MFCs to be practical. This paper analysed MFC operating principles using bioenergetics and bioelectrochemistry. Several major issues were explored to improve the MFC performance. An emphasis was placed on the use of catalytic materials for MFC electrodes. Recent advances in the production of various biomaterials using MFCs were also investigated. [ABSTRACT FROM PUBLISHER]

Owing to high petroleum prices, there has been a major push in recent years to use lignocellulosic biomass as biorefinery feedstocks. Unfortunately, by nature's design, lignocellulosic biomass is notoriously recalcitrant. Cellulose is the most abundant renewable carbon source on the planet and comprises glucan polysaccharides which self-assemble into paracrystalline microfibrils. The extent of cellulose crystallinity largely contributes to biomass recalcitrance. Additionally, cellulose microfibrils are embedded into both hemicellulose and lignin polymeric networks, making cellulose accessibility an additional obstacle. Pretreatment is necessary before enzymatic hydrolysis in order to liberate high yields of glucose and other fermentable sugars from biomass polysaccharides. This work discusses two pretreatment methods, supercritical CO2and ionic liquids (ILs). Both methods utilize green solvents that do not emit toxic vapours. Mechanisms for destroying or weakening biomass recalcitrance have been explored. Various pretreatment operating parameters such as temperature, pressure, time, dry biomass/solvent ratio, water content, etc. have been investigated for the pretreatment of various biomass types such as corn stover, switchgrass, sugarcane bagasse, soft and hard wood. The two pretreatment methods have their pros and cons. For example, supercritical CO2explosion pretreatment uses inexpensive CO2, but requires a high pressure. By comparison, while IL pretreatment does not require an elevated pressure, ILs are still too expensive for large-scale uses. Further research and development are needed to make the two green pretreatment methods practical. [ABSTRACT FROM PUBLISHER]

The kinetics of cell growth and protein production for the recombinant Aspergillus niger strain AB4.1[pgpdAGLAGFP]#11 were investigated. An unstructured kinetic model was developed to describe the cell growth and product formation mathematically. The dynamics of glucose consumption and biomass production can be well-described by the model. The assumption that the degradation of GFP by proteases is a first-order reaction can express the trend of the GFP profile reasonably well. The dynamics of protease production is also described reasonably well by considering the inhibition effect of glucose on protease production. Because of the high initial glucose concentration and keeping the pH value of the broth at 6, the protease activity could be kept low most of the time during the fermentation. The increase of protease activity near the end of the culture might be caused by cell lysis because the intracellular protease activity was much higher than the extracellular activity. [ABSTRACT FROM AUTHOR]

Liquid-liquid equilibrium (LLE) occurs at a subzero temperature for the acetonitrile-water binary system. When the equilibrium temperature is below its LLE critical temperature of - 1.32°C, the top phase is acetonitrile-rich and the bottom phase water-rich. It was observed that a human growth hormone analog with 191 amino acids partitioned exclusively into the bottom phase and its bioactivity was retained. This suggests that the liquid-liquid partition system can be used for bioseparations. The new system gives a different selectivity and the low temperature environment offers better stabilities for biomolecules compared to conventional solvent extraction systems. This work presented the partition coefficients of some biomolecules including trypsin, thyroglobulin, transferrin, ribonuclease A; L-phenylalanine, L-tryptophan; val-ala-ala-phe, phe-gly-gly-phe; erythromycin, chloramphenicol, vancomycin, spiramycin, gramicidin D, cycloheximide, fusidic acid, antimycin and tetracycline. Temperature and pH effects, as well as partition mechanisms were probed. [ABSTRACT FROM AUTHOR]

The flexible and automatic monitoring and control of a 22  L B. Braun Biostat C fermenter using LabVIEW software were achieved by establishing a serial interface between the fermenter's control unit and a personal computer. This setup was also used for the on-line monitoring of the DO change in a custom-made 50  L airlift bioreactor. [ABSTRACT FROM AUTHOR]