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See detailMétabolisme phosphocalcique: prescription et impact économique
CAVALIER, Etienne ULg

Conference (2012, May 12)

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See detailMetabolites from media supplemented with 3’-sialyllactose and fermented by bifidobacteria have an antivirulent effect against intestinal pathogens
Bondue, Pauline ULg; Daube, Georges ULg; Delcenserie, Véronique ULg

Poster (2016, October 21)

Complex oligosaccharides from human milk (HMO) promote growth of Bifidobacterium bifidum. Oligosaccharides from cow milk (BMO), similar to HMO, are mainly represented in colostrum by 3’-sialyllactose ... [more ▼]

Complex oligosaccharides from human milk (HMO) promote growth of Bifidobacterium bifidum. Oligosaccharides from cow milk (BMO), similar to HMO, are mainly represented in colostrum by 3’-sialyllactose (3’SL). Bifidobacterium crudilactis, a species from bovine origin and encoding for β galactosidases and α-glucosidases, could be able to metabolise them. Also, fermentation products could have antivirulent activity against intestinal pathogens. This study focused on capacity of bifidobacteria to metabolise 3’SL and on potential antivirulent effect of cell-free spent media (CFSM) against pathogenic bacteria. B. bifidum BBA1 and B. crudilactis FR/62/B/3 isolated respectively from breastfed children feces and cow raw milk cheese were grown on media supplemented with 3’SL as sole source of carbon. Next, CFSM effects were tested against virulence gene expression using ler and hilA promoter activity of luminescent constructs of Escherichia coli 0157:H7 ATCC 43888 and Salmonella Typhimurium SA 941256, respectively. The effect was confirmed on wild type strains of E. coli O157:H7 ATCC 43890 and S. Typhimurium ATCC 14028 using RT-qPCR. Both strains were able to grow in presence of 3’SL. CFSM resulted in under-expression of hilA and ler genes for the luminescent constructs and in under-expression of ler (ratios of -15.4 and -8.1) and qseA (ratios of -2.1 and -3.1) genes for the wild type strain of E. coli O157:H7. No effect was observed with S. Typhimurium. Little is known about CFSM metabolites and they have to be isolated and identified. The potential synbiotic effect between 3’SL and bifidobacteria will be tested using the Shime®, a human gastrointestinal model. [less ▲]

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See detailMetabolites from media supplemented with 3’-sialyllactose and fermented by bifidobacteria have an antivirulent effect against intestinal pathogens
Bondue, Pauline ULg

Poster (2016, September 16)

Introduction Complex oligosaccharides from human milk (HMO) promote growth of bifidobacteria such as Bifidobacterium bifidum [1]. Whey, a by-product of dairy-industry, contents complex oligosaccharides ... [more ▼]

Introduction Complex oligosaccharides from human milk (HMO) promote growth of bifidobacteria such as Bifidobacterium bifidum [1]. Whey, a by-product of dairy-industry, contents complex oligosaccharides (BMO) similar to HMO, which are mainly represented in colostrum by 3’-sialyllactose (3’SL) [2]. Bifidobacterium crudilactis, a species of bovine origin, encodes for β galactosidases and α-glucosidases and could therefore be able to metabolise those BMO [3; 4; 5]. In addition, fermentation products from bifidobacteria can produce antivirulent activity against intestinal pathogenic bacteria [6; 7]. This study focused on capacity of bifidobacteria to metabolise BMO, more particularly 3’SL, and on potential antivirulent effect of cell-free spent media (CFSM) against virulence gene expression of pathogenic bacteria. Material and methods B. bifidum BBA1 and B. crudilactis FR/62/B/3 isolated respectively from breastfed children feces and from cow raw milk cheese were grown on media supplemented with BMO or 3’SL, as sole source of carbon. The CFSM were harvested after centrifugation of cells culture, freeze-dried and concentrated 10 fold. Next, their effects were tested against virulence gene expression using ler and hilA promoter activity of luminescent constructs of Escherichia coli 0157:H7 ATCC 43888 and Salmonella Typhimurium SA 941256, respectively. The effect was confirmed on wild type strains of E. coli O157:H7 ATCC 43890 and S. Typhimurium ATCC 14028 using RT-qPCR. Results Both strains were able to grow in presence of whey or 3’SL, but B. crudilactis showed the best growth compared to B. bifidum. The highest cell concentrations were observed with media containing whey (8.9 ± 0.6 log cfu/ml and 8.1 ± 0.3 log cfu/ml, respectively). CFSM from fermented media supplemented with 3’SL resulted in under-expression of hilA and ler genes for the luminescent constructs and in under-expression of ler (ratios of -15.4 and -8.1) and qseA (ratios of -2.1 and -3.1) genes for the wild type strain of E. coli O157:H7. No effect was observed for the wild type strain of S. Typhimurium. Discussion B. crudilactis presented the best growth potential probably because its genome encodes the enzymatic machinery to use BMO (β galactosidases and α-glucosidases) [3; 4; 5]. The positive effect of media supplemented with milk products on growth of probiotics has been demonstrated previously [8]. CFSM obtained from media supplemented with 3’SL down-regulate several virulence genes of E. coli O157:H7 and potentially S. Typhimurium. This effect has been observed previously with CFSM obtained from fermentation of lactic acid bacteria or bifidobacteria, by production of antivirulent metabolites [2; 3]. BMO combined with some bifidobacteria strains of bovine or human origin could therefore be an interesting synbiotic to maintain or restore the intestinal health of young children. These effects observed in vitro will be further investigated regarding the exact nature of the active molecules. References 1. Garrido D. et al. (2013). Microbiology 159: 649-664. 2. Urashima T. et al. (2013). Biosci Biotechnol Biochem 77: 455-466. 3. Sela D. A. (2011). Int J Food Microbiol 149: 58-64. 4. Milani C. et al. (2014). Appl Environ Microbiol 80: 6290-6302. 5. Bondue P. & Delcenserie V. (2015). Korean J Food Sci Anim Resour 35: 1-9. 6. Medellin-Pena M. J. et al. (2007). Appl Environ Microbiol 73: 4259-4267. 7. Bayoumi M. A. & Griffiths M. W. (2012). Int J Food Microbiol 156: 255-263. 8. Champagne C. P. et al. (2014). Can J Microbiol 60: 287-295. [less ▲]

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See detailThe metabolome of developing pea seeds
Vigeolas, Hélène ULg

Conference (2007)

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See detailMetabolomic analysis of Echinacea spp. by (1)H nuclear magnetic resonance spectrometry and multivariate data analysis technique.
Frederich, Michel ULg; Jansen, C.; De Tullio, Pascal ULg et al

in Phytochemical Analysis (2010), 21(1), 61-65

Introduction - The genus Echinacea (Asteraceae) comprises about 10 species originally distributed in North America. Three species are very well known as they are used worldwide as medicinal plants ... [more ▼]

Introduction - The genus Echinacea (Asteraceae) comprises about 10 species originally distributed in North America. Three species are very well known as they are used worldwide as medicinal plants: Echinacea purpurea, E. pallida, E. angustifolia.Objective - To discriminate between these three Echinacea species and E. simulata by (1)H NMR-based metabolomics.Methodology - (1)H NMR and multivariate analysis techniques were applied to diverse Echinacea plants including roots and aerial parts, authentic plants, commercial plants and commercial dry extracts.Results - Using the (1)H NMR metabolomics, it was possible, without previous evaporation or separation steps, to obtain a metabolic fingerprint to distinguish between species.Conclusion - A clear distinction between the three pharmaceutical species was possible and some useful metabolites were identified. Copyright (c) 2009 John Wiley & Sons, Ltd. [less ▲]

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See detailMetabolomic analysis of Strychnos nux-vomica, Strychnos icaja and Strychnos ignatii extracts by H-1 nuclear magnetic resonance spectrometry and multivariate analysis techniques
Frederich, Michel ULg; Choi, Young Hae; Angenot, Luc ULg et al

in Phytochemistry (2004), 65(13), 1993-2001

H-1 Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos nux-vomica (seeds, stem bark, root bark ... [more ▼]

H-1 Nuclear magnetic resonance spectrometry and multivariate analysis techniques were applied for the metabolic profiling of three Strychnos species: Strychnos nux-vomica (seeds, stem bark, root bark), Strychnos ignatii (seeds), and Strychnos icaja (leaves, stem bark, root bark, collar bark). The principal component analysis (PCA) of the H-1 NMR spectra showed a clear discrimination between all samples, using the three first components. The key compounds responsible for the discrimination were brucine, loganin, fatty acids.. and Strychnos icaja alkaloids such as icajine and sungucine. The method was then applied to the classification of several "false angostura" samples. These samples were, as expected, identified as S. nux-vomica by PCA, but could not be clearly discriminated as root bark or stem bark samples after further statistical analysis. (C) 2004 Published by Elsevier Ltd. [less ▲]

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See detailMetabolomic analysis of the green microalga Chlamydomonas reinhardtii cultivated under day/night conditions
Willamme, Rémi ULg; Alsafra, Zouheir; Arumugam, Rameshkumar et al

in Journal of Biotechnology (2015)

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See detailMetabolomic and molecular signatures of Mascarene Aloes using a multidisciplinary approach
Govinden-Soulange, J.; Lobine, D.; Frederich, Michel ULg et al

in South African Journal of Botany (2017), 108

In this research a multidisciplinary approach was used to unveil the genetic, metabolic uniqueness and relationships of endemic Mascarene Aloes (Aloe macra, Aloe purpurea, Aloe tormentorii) with respect ... [more ▼]

In this research a multidisciplinary approach was used to unveil the genetic, metabolic uniqueness and relationships of endemic Mascarene Aloes (Aloe macra, Aloe purpurea, Aloe tormentorii) with respect to Aloe vera. Nuclear magnetic resonance spectroscopy, DNA sequencing and antioxidant profiles of these Aloes were studied. Principal component analysis following 1H NMR revealed the specificity of the Mascarene Aloes relative to Aloe vera. The superior free radical scavenging ability of A. purpurea, A. macra and A. tormentorii as compared to other Aloes was also unveiled. Phylogenetic analyses of chloroplast genes and ITS region sequences of these Mascarene Aloes were done using maximum parsimony and Bayesian analysis. Mascarene Aloes clustered within one clade separate from Aloe vera confirming their relative recent emergence in this genus. Results from this study showed that there is sufficient evidence at the metabolomic and molecular level to distinguish between Aloe ​purpurea from Mauritius and that of Reunion. © 2016 SAAB [less ▲]

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See detailMetabolomic investigation of the ethnopharmacological use of Artemisia afra with NMR Spectroscopy and Multivariate Data Analysis.
Liu, N. Q.; Cao, Martine ULg; Frederich, Michel ULg et al

in Journal of Ethnopharmacology (2010), 128

Ethnopharmacological relevance: Artemisia afra has been used as an infusion to treat malaria throughout the southern parts of Africa, in much the same way as the antimalarial plant Artemisia annua in ... [more ▼]

Ethnopharmacological relevance: Artemisia afra has been used as an infusion to treat malaria throughout the southern parts of Africa, in much the same way as the antimalarial plant Artemisia annua in China. The antiplasmodial activity of purified components from an apolar fraction of A. afra has been shown in the past. No data on the efficacy of the tea infusion prepared from A. afra are however available. OBJECTIVE: To investigate the antiplasmodial activity of various extracts of A. afra including an ethnopharmacological prepared sample. To identify polar metabolites in A. afra and A. annua and by using multivariate data analysis investigate the metabolic differences between these species. Materials and methods: The antiplasmodial activity of A. afra and A. annua extracts were tested for activity against Plasmodiam falciparum 3D7 (chloroquine-sensitive strain) with chloroquine, quinine and artemisinin as positive controls. Hydrophilic metabolites in A. afra and A. annua were identified directly from the crude extracts through 1D- and 2D-NMR spectra. The NMR spectra were also used to differentiate between the two species using principal component analysis (PCA) for quality control purposes. RESULTS: The apolar fractions of both A. afra and A. annua showed activity against P. falciparum while activity was only found in the tea infusion of A. annua. Metabolomic studies using 1D- and 2D-NMR spectroscopy identified 24 semi-polar components in A. afra including three new phenylpropanoids for this species: caffeic acid, chlorogenic acid and 3,5-dicaffeoyl quinic acid. PCA analysis conducted on the samples yielded good separation between the polar extracts of A. afra and A. annua. CONCLUSION: These findings shows that there are no in vitro activity in the tea infusion of A. afra and lists the identified metabolites causing the metabolic differences between A. afra and A. annua for quality control purposes. [less ▲]

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