A microbial sensor platform based on bacterial bioluminescence (luxAB) and green fluorescent protein (gfp) reporters for in situ monitoring of toxicity of wastewater nitrification process dynamics.

To avoid the upset of nitrification process in wastewater treatment plants, monitoring of influent toxic chemicals is essential for stable operation. Toxic chemical compounds can interfere with the biological nitrogen removal, thus affecting plant efficiency and effluent water quality. Here we report the development of fluorescence and bioluminescence bioassays, based on E. coli engineered to contain the promoter region of ammonia oxidation pathway (AmoA1) of Nitrosomonas europaea and a reporter gene (lux or gfp). The fluorescence or bioluminescence signal was measured with newly designed optical devices. The microbial sensors were tested and validated at different concentrations of nitrification-inhibiting compounds such as allylthiourea, phenol, and mercury. The signal decrease was immediate and proportional to inhibitor concentration. The developed bacterial bioassays could detect the inhibition of the nitrification process in wastewater for allylthiourea concentrations of 1 µg/L for E.coli pMosaico-Pamo-gfp and 0.5 µg/L for E.coli pMosaico-Pamo-luxAB. The results were confirmed using water from a wastewater plant, containing nitrification-inhibiting compounds.

ZnO/polyaniline composite based photoluminescence sensor for the determination of acetic acid vapor.

In this study, we report a novel ZnO/polyaniline (PANI) nanocomposite optical gas sensor for the determination of acetic acid at room temperatures. ZnO nanorods, synthesized in powder form were coated by PANI (ZnO/PANI) by chemical polymerization method. The obtained nanocomposites were deposited on glass substrate and dried overnight at room temperature. Structure and optical properties of ZnO/PANI nanocomposite have been studied by using X-ray diffraction, transmission electron microscopy, scanning electron microscopy, diffuse reflectance and photoluminescence spectroscopy. Tests towards acetic acids were performed in the range of concentrations 1-13 ppm. The adsorption of acetic acid on the sensor's surface resulted in the decrease of ZnO/PANI photoluminescence. The response and recovery time of the sensor were in the range of 30-50 s and 5 min, respectively. The developed sensors showed sensitivity towards acetic acid in a range of 1-10 ppm with the limit of detection of 1.2 ppm. Specially designed miniaturized sensing system based on integrated sensing layer, light emission diode as excitation source and optical fiber spectrometer was developed for the measurement of the sensor signal. The developed sensing system was applied for the investigation of some real sample assessment including the evaluation of storage conditions of ancient cellulose acetate films, which during the degradation are releasing acetic acid. The obtained results suggest that the developed novel optical ZnO/PANI nanocompsite based sensor shows great potential for acetic acid determination in various samples.

An overview of the functional food market: from marketing issues and commercial players to future demand from life in space.

Companies in the food industry have high expectations for food products that meet the consumers' demand for a healthy life style. In this context Functional Food plays a specific role. These foods are not intended only to satisfy hunger and provide the necessary human nutrients, but also to prevent nutrition-related diseases and increase the physical and mental well-being of their consumer. Among participants in space science and missions, recognition of nutraceuticals and dietary supplements is growing for their potential in reducing health risks and to improve health quality and eating habits during long-term flights and missions. In 2008 the entire functional foods market was worth over an estimated US $80 billion, with the US holding a majority share in the nutraceuticals market (35%) followed byJapan (25%) and with the ever-growing European market, currently estimated at US$8 billion. India and China are the two major countries known for their production of traditional functional food products and nutraceuticals, but other South-East Asian countries and Gulf nations are developing potential markets.

Legislation on nutraceuticals and food supplements: a comparison between regulations in U.S.A. and E.U.

This chapter provides a short review of the main regulations concerning functional food and nutraceutical products set out by the U.S. Food and Drug Administration and in the European Union by the European Commission. The directives are presented in chronological order with an overview on the reaction and feedback they received from consumers and manufacturing industry. A comparison between the U.S. and E.U. regulations, their acceptance and impact on the market is presented, together with a final suggestion to enhance the future development and distribution of functional products, which belong to an equivocal area between food and drugs.