Abstracts / Journal of Biotechnology 136S (2008) S711–S716
them has been found related to the pathogenesis of the bacteria (Wang et al., 2007). Modiﬁcation of the structure of lipid A could be regulated by special systems in some bacteria, such as Salmonella typhimurium. It is not fully understood how the bacteria increase their power of infection by changing the structure of their lipid A. Because of its speciﬁc chemical structure, lipid A can be used as a marker for detection of some Gram-negative pathogens in food, such as Campylobacter jejuni, Salmonella and Shigella. Keywords: Lipid A; Lipopolysaccharide; Gram-negative bacteria References Wang, X., Karbarz, M.J., McGrath, S.C., Cotter, R.J., Raetz, C.R., 2004. MsbA transporter dependent lipid A 1-dephosphorylation on the periplasmic surface of the inner membrane: topography of Francisella novicida LpxE expressed in Escherichia coli. J. Biol. Chem. 279, 49470–49478. Wang, X., McGrath, S.C., Cotter, R.J., Raetz, C.R., 2006a. Expression cloning and periplasmic orientation of the Francisella novicida lipid A 4 -phosphatase LpxF. J. Biol. Chem. 281, 9321–9330. Wang, X., Ribeiro, A.A., Guan, Z., McGrath, S., Cotter, R., Raetz, C.R.H., 2006b. Structure and biosynthesis of free lipid A molecules that replace lipopolysaccharide in Francisella tularensis subsp. novicida. Biochemistry 45, 14427–14440. Wang, X., Ribeiro, A.A., Guan, Z., Abraham, S., Raetz, C.R.H., 2007. Attenuated virulence of a Francisella mutant lacking the lipid A 4 -phosphatase. Proc. Natl. Acad. Sci. U.S.A. 104, 4136–4141.
doi:10.1016/j.jbiotec.2008.07.1693 KN-033 Biotechnological approaches to improve food quality Roberto Tuberosa Department of Agroenvironmental Sciences and Technology, University of Bologna, Viale Fanin 44, 40127 Bologna, Italy Food quality is of paramount importance to the agro-food industry and for the health of farm animals and humans. More than half the world’s people, particularly in developing countries, suffer from vitamin A, zinc and iron deﬁciency due to a poor diet. Biotechnology offers great potential to improve food quality through forwardand reverse-genetics approaches that enable us to clone the relevant genes and QTLs (Tuberosa and Salvi, 2007; Uauy et al., 2006). In cereals, association mapping (Harjes et al., 2008) and TILLING (Slade et al., 2005) have allowed for the identiﬁcation of novel alleles able to improve seed quality. Once relevant genes are identiﬁed, their expression level can be altered either through marker-assisted selection or genetic engineering, by far the preferred alternative, though not necessarily the most effective (Mayer et al., 2008; Enserink, 2008). The enrichment in provitamin A is a notable example of a genetic engineering approach to enhance crop nutritional quality (Enserink, 2008). Additionally, genetic engineering offers signiﬁcant potential to enhance the capacity of crops to acquire micronutrients from the soil and to store them in the seeds. Other relevant examples will be reviewed. An effective impact of biotechnology will require its integration with extant breeding programs. References Enserink, M., 2008. Tough lessons from golden rice. Science 320, 468–471. Harjes, C.E., et al., 2008. Natural genetic variation in lycopene epsilon cyclase tapped for maize biofortiﬁcation. Science 319, 330–333. Mayer, J.E., et al., 2008. Biofortiﬁed crops to alleviate micronutrient malnutrition. COPB 11, 166–170. Slade, A.J., et al., 2005. A reverse genetic, nontransgenic approach to wheat crop improvement by TILLING. Nat. Biotechnol. 23, 75–81. Tuberosa, R., Salvi, S., 2007. Cloning QTLs in plants. In: Varshney, R.K., Tuberosa, R. (Eds.), Genomics-Assisted Crop Improvement, vol. 1. Springer, Dordrecht, pp. 207–226.
Uauy, C., et al., 2006. A NAC gene regulating senescence improves grain protein, zinc, and iron content in wheat. Science 314, 1298–1301.
doi:10.1016/j.jbiotec.2008.07.1694 KN-034 Production of novel compounds by enzymes and their application to foods Takashi Kometani Health Science Laboratory, Ezaki Glico Co., Ltd., Osaka, Japan E-mail address: [email protected]
Recently many people have been paying attention to their health, and the great needs to use physiologically functional foods were occurred in the markets. As a result, the size of their market in Japan became approximately 700 billion yen in 2007. Many enzymes have been used in food processing, for example, production of a wide variety of dextrin from starch by amylases, improvement of meat tenderization by proteases, etc. The aim of this study was the production of novel bioactive compounds by enzymes, and the research and development of physiologically functional foods using these compounds. Hesperidin is a ﬂavanone found abundantly in citrus fruits, and known to have many biological activities such as reduction of cholesterol and blood pressure, etc. Glucosylhesperidin (Hsp-G) was produced from hesperidin by the transglucosylation using cyclodextrin glucanotransferase (Kometani et al., 1994). Oral administration of Hsp-G was found to improve poor blood circulation in women and rheumatoid arthritis (Kometani et al., 2008). Phosphoryloligosaccharides of calcium (POs–Ca) was a soluble complex with calcium and phosphoryloligosaccharides prepared from potato starch by a combination of amylase-related enzymes. When the volunteers were chewing the dental gums including POs–Ca four times/day, it was proved to prevent dental caries (Kamasaka et al., 2004). Cyclic cluster dextrin (CCD) was produced from amylopectin by branching enzyme, which had a relatively narrow molecular weight distribution compared with commercially available dextrins. In addition, as the dextrin is highly water-soluble, low viscosity and having no taste, it was used as a energy source of sports drinks. As a result, it was found that swimming endurance was enhanced very much in both mice (Takii et al., 1999) and humans. In conclusions, we produced novel compounds, Hsp-G, POs–Ca and CCD, and applied to improvement of poor blood circulation and rheumatoid arthritis as a supplement and a drink, prevention of dental caries as a chewing gum and enhancement of endurance performance as a sports drink, respectively. References Kamasaka, H., Inaba, D., Minami, K., To-o, K., Nishimura, T., Kuriki, T., Imai, S., Hanada, N., Yonemitsu, M., 2004. Application of phosphoryl oligosaccharides of calcium (Pos–Ca) for oral health. J. Appl. Glycosci. 51, 129–134. Kometani, T., Terada, Y., Nishimura, T., Takii, H., Okada, S., 1994. Transglycosylation to hesperidin by cyclodextrin glucanotransferase from an alkalophilic Bacillus species in alkaline pH and properties of hesperidin glycosides. Biosci. Biotechnol. Biochem. 58, 1990–1994. Kometani, T., Fukuda, T., Kakuma, T., Kawaguchi, K., Tamura, W., Kumazawa, Y., Nagata, K., 2008. Effects of alpha-glucosylhesperidin, a bioactive food material, on collagen-induced arthritis in mice and rheumatoid arthritis in humans. Immunopharmacol. Immunotoxicol. 30, 117–134. Takii, H., Ishihara, K., Kometani, T., Okada, S., Fushiki, T., 1999. Enhancement of swimming endurance in mice by highly branched cyclic dextrin. Biosci. Biotechnol. Biochem. 63, 2045–2052.