Osmoprotectants enhance methane production from the anaerobic digestion of food wastes containing a high content of salt

BACKGROUND: Treatment and disposal of Korean food waste encounter technical difficulties due to a high‐salt problem. In order to increase methane production from food waste by using osmoprotectants, which are known to overcome osmotic stresses in many plants and other organisms, osmoprotectants including glycine betaine, choline, carnitine and trehalose were added to salt‐containing food wastes for anaerobic digestion. RESULTS: For NaCl‐amended food wastes containing 10 and 35 g L^?1 NaCl, glycine betaine and choline increased methane production by about twofold compared to food waste without any osmoprotectants. For non‐washed food waste containing 11.6 g L^?1 NaCl, glycine betaine increased methane production by about sixfold. Among these osmoprotectants, glycine betaine was the most effective for increasing methane productivity in anaerobic digestion of food waste with salinity. Analysis of glycine betaine in cell extracts using high‐performance liquid chromatography showed that glycine betaine accumulated in the cells of anaerobic sludge. CONCLUSION: Osmoprotectants significantly enhanced methanization of high‐salt food wastes by alleviating the salt‐induced physiological stresses in microorganisms. The application of osmoprotectants provided an effective substitute for other conventional methods to reduce inhibitory effects of high salt, such as dilution and co‐digestion. Copyright © 2008 Society of Chemical Industry     

Reuse of low concentrated electronic wastewater using selected microbe immobilised cell system.

This work describes a novel technology for the reuse of low concentrated electronic wastewater using selected microbe immobilisation cell (SMIC) system. The SMIC system is an innovative technology to maximise the activity of specific microorganisms capable of decomposing tetramethyl ammonium hydroxide (TMAH) as a major organic compound in the low concentrated electronic wastewater. The versatility of the SMIC system has been studied by using continuous-flow reactors. The TOC in a SMIC system was removed completely, indicating that SMIC is a useful technology to remove TOC biologically in low concentrated wastewater. The most important advantages of this system are highly effective and stable in view of TMAH removal. These characteristics make well suited to various applications depending on targeted compounds and microorganisms and, especially, in the wastewater of electronic facilities.     

Nonlinear optical polymers with novel benzoxazole chromophores II. Synthesis of polyurethanes with good thermal stability

Novel diol monomer having a π-conjugated benzoxazole ring, 2-(4-nitrophenyl)-6-[N,N-bis(2-hydroxyethyl)amino]benzoxazole was successfully synthesized to improve the thermally stability of nonlinear optical chromophores. Several polyurethanes bearing pendant benzoxazole chromophores were obtained by polyaddition of the diol to various aromatic diisocyanates. The thermal stability of these polyurethanes were monitored by thetrnogravimetry and IR spectroscopy, and compared with other polyurethanes having general pendant azo chromophores. The poled polyurethane films exhibited large and stable second-order nonlinear optical properties.     

Personality traits and effectiveness of presentation of product information in e-business systems

Consumer interaction with product information is one of the critical components in business-to-consumer (B2C) e-commerce environments. Online consumers' characteristics can be expected to play an important role when designing how product information is presented in such e-commerce environments. We suggest that online consumers' personality traits impact effectiveness of the presentation of product information on e-commerce sites and the extent to which the various e-commerce environments are effective. In this article, we propose and empirically validate relationships among online consumers' personality traits, product information presentation richness and on-line consumer behaviour in e-commerce environments. Results show that effectiveness of product information presentation varies by online consumers' psychological types, and that rich product information presentation significantly influences the online buying behaviour of intuitive types, and feeling types, rather than sensing and thinking types. Discussion of the results and their implications for theory and practice as well as limitations and future research directions are presented.     

Physicochemical characterization of rutaecarpine-loaded microemulsion system

To develop an o/w microemulsion system containing poorly water-soluble rutaecarpine, the solubility of rutaecarpine in water, ethanol, various oils, and surfactants were investigated. Among the surfactants and oils tested, Tween 20/PEG 400 and castor oil were chosen as the surfactant system and oil phase of the microemulsion, as rutaecarpine was most soluble in them, respectively. Pseudoternary phase diagrams were constructed to obtain the concentration range of oil, surfactant, and cosurfactant for microemulsion formation, and the stability test of rutaecarpine delivered by microemulsion formation was then evaluated. Pseudoternary phase diagrams show that the areas of microemulsion appeared at those with 0-20% Smix (PEG 400/Tween80 = 60/40), 64-81% water, and 10-20% oil. The rutaecarpine (300 µg/g)-loaded microemulsion composed of 10.8% PEG 400, 7.2% Tween 80, 20% caster oil, and 72% water was physically and chemically stable for at least 6 months. Thus, the microemulsion system composed of castor oil, PEG 400, Tween 80, and water could be a stable dosage form for rutaecarpine.     

Improved cell viability of biocompatible nutrient-contained polymeric nanofibers

Nanofibers containing cell nutrients (PGDs) were fabricated by mixing 5 wt% poly(epsilon-caprolactone) (P), 4 wt% gelatin (G), and 0-2.4 wt% Dulbecco's Modified Eagle's Medium (D). The contact angles showed a considerable decrease from 118.4 degrees on the P scaffold to 17.6 degrees on PGD1.6 (containing 1.6 wt% D). The weight loss ratios between PGD1.6 and the P nanofiber, and between PGD1.6 and the PG nanofiber by degradation after 28 days were approximately 3.1 and 1.4, respectively. The rate of cell proliferation on PGD1.6 was greater than that on the PG nanofiber by 14% and 38% for the exchanged and unexchanged culture media, respectively. The physicochemical measurement results showed that the PGDs exhibited enhanced hydrophilic properties and rapid biodegradation. The PGD nanofibers with increasing D content showed better conditions for long-term cell viability. The growth mechanism of the cells on the PGDs was explained by an attachment and growth process.