Chicory root
RNA interference (RNAI) as a tool to engineer high nutritional value in chicory (Chicorium intybus).
1: Commun Agric Appl Biol Sci. 2006;71(1):75-8.
RNA interference (RNAI) as a tool to engineer high nutritional value in chicory (Chicorium intybus).
Department of Plant Production, Faculty of Agricultural and Applied Biological Sciences, Ghent University Coupure Links 653, BE-9000 Gent, Belgium. Asad.Maroufi@ugent.be
The major component of chicory (Chicorium intybus) root is inulin, which is a polymer of fructose. Inulin production from chicory is hampered by the enzyme fructan 1-exohydrolase (1-FEH) that degrades inulin and limits its yield. Increased FEH activity results in massive breakdown of fructan and production of Fructose and inulo-n-oses. The latter phenomena are to be avoided for industrial fructan production. RNA silencing, which is termed post-transcriptional gene silencing (PTGS) in plants, is an RNA degradation process through sequence specific nucleotide interactions induced by double-stranded RNA. For genetic improvement of crop plants, RNAi has advantages over antisense-mediated gene silencing and co-suppression, in terms of its efficiency and stability. We are generating a transgenic chicory plants with suppressed FEH (exohydrolas) genes using RNAi resulting in supressed inulin degradation. A small but important part of the construct is a sequence unique for the target gene (exons) or genes,which were cloned. The hairpin constructs were made and chicory was transformed by Agrobacterium tumifaciense, strain (C58C1). The transgenics should be select and check by means of molecular techniques.
PMID: 17191477 [PubMed - indexed for MEDLINE]
Impact of inulin and oligofructose on gastrointestinal peptides
1: Br J Nutr. 2005 Apr;93 Suppl 1:S157-61.
Impact of inulin and oligofructose on gastrointestinal peptides.
Unit of Pharmacokinetics, Metabolism, Nutrition and Toxicology, MD/FARM/PMNT 7369, Universite Catholique de Louvain, Avenue E Mounier 73, B-1200 Brussels, Belgium. Delzenne@pmnt.ucl.ac.be
In the present paper, we summarise the data supporting the following hypothesis: dietary inulin-type fructans extracted from chicory root may modulate the production of peptides, such as incretins, by endocrine cells present in the intestinal mucosa, this phenomenon being involved in the regulation of food intake and/or systemic effects. To test this hypothesis, male Wistar rats received for 3 weeks either a standard diet or the same diet supplemented with 10 % inulin-type fructans with different degrees of polymerisation. All the effects were most pronounced with the diet containing oligofructose, and consisted of (i) a decrease in mean daily energy intake and in epididymal fat mass; (ii) a higher caecal pool of the anorexigenic glucagon-like peptide-1 (7-36) amide (GLP-1), and peptide YY (PYY), due to caecal tissue proliferation; (iii) an increase in GLP-1 and of its precursor - proglucagon mRNA - concentrations in the proximal colon; (iv) an increase in portal serum level of GLP-1 and PYY; (v) a decrease in serum orexigenic peptide ghrelin. Moreover, oligofructose supplementation improved glucose homeostasis (i.e. decreased glycaemia, increased pancreatic and serum insulin content) in diabetic rats previously treated with streptozotocin, a phenomenon that is partly linked to the reduction in food intake and that correlates with the increase in colic and portal GLP-1 content. Based on these results it appears justified to test, in human subjects, the hypothesis that dietary inulin-type fructans could play a role in the management of obesity and diabetes through their capacity to promote secretion of endogenous gastrointestinal peptides involved in appetite regulation.
PMID: 15877889 [PubMed - indexed for MEDLINE]
Inhibition of the expression and activity of cyclooxygenase-2 by chicory extract
1: Biochem Biophys Res Commun. 2005 Feb 18;327(3):742-9.
Inhibition of the expression and activity of cyclooxygenase-2 by chicory extract.
Quality and Safety Department, Nestle Research Center, P.O. Box 44, Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland. Christophe.Cavin@rdls.nestle.com
Chicory is a major source of fructans with reported prebiotic-bifidogenic properties. In the present study, the potential anti-inflammatory activities of chicory were investigated. Ethyl acetate chicory root extract produced a marked inhibition of prostaglandin E(2) (PGE(2)) production in human colon carcinoma HT29 cells treated with the pro-inflammatory agent TNF-alpha. Two independent mechanisms of action were identified: (1) a drastic inhibition of the induction by TNF-alpha of cyclooxygenase 2 (COX-2) protein expression and (2) a direct inhibition of COX enzyme activities with a significantly higher selectivity for COX-2 activity. The inhibition of TNF-alpha-dependent induction of COX-2 expression was mediated by an inhibition of NF-kappaB activation. A major sesquiterpene lactone of chicory root, the guaianolide 8-deoxylactucin, was identified as the key inhibitor of COX-2 protein expression present in chicory extract. Altogether, the data presented strongly support chicory root as a promising source of functional food ingredient, combining prebiotic and anti-inflammatory properties.
PMID: 15649409 [PubMed - indexed for MEDLINE]
Probiotics and prebiotics: A brief overview
1: J Ren Nutr. 2002 Apr;12(2):76-86.
Probiotics and prebiotics: A brief overview.
Strategic-Discovery Research and Development, Ross Products Division, Abbott Laboratories, Columbus, OH 43215-1724, USA.
Probiotics and prebiotics are 2 food ingredients that confer physiologic effects through the gastrointestinal tract. Probiotics have been defined as viable microorganisms that (when ingested) have a beneficial effect in the prevention and treatment of specific pathologic conditions. These microorganisms are believed to exert biological effects through a phenomenon known as colonization resistance, whereby the indigenous anaerobic flora limits the concentration of potentially pathogenic (mostly aerobic) flora in the digestive tract. Other modes of action, such as supplying enzymes or influencing enzyme activity in the gastrointestinal tract, may also account for some of the other physiologic effects that have been attributed to probiotics. Conversely, prebiotics are nondigestible food ingredients that beneficially affect host health by selectively stimulating the growth and/or activity of 1 or a limited number of bacteria in the colon. The prebiotic, fructooligosaccharide (FOS), is found naturally in many foods, such as wheat, onions, bananas, honey, garlic, or leeks. They can also be isolated from chicory root or synthesized enzymatically from sucrose. Fermentation of FOS in the colon results in a large number of physiologic effects including increasing the numbers of bifidobacteria in the colon, increasing calcium absorption, increasing fecal weight, shortening of gastrointestinal transit time, and possibly lowering blood lipid levels. Other effects that have been observed in animal models include an increase in cecal weight and an increase in fecal nitrogen excretion. The increase in bifidobacteria has been assumed to benefit human health by producing compounds to inhibit potential pathogens, by reducing blood ammonia levels, and by producing vitamins and digestive enzymes. Copyright 2002 by the National Kidney Foundation, Inc.
PMID: 11953920 [PubMed - indexed for MEDLINE]
