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Le présent travail analyse l’impact des conditions nutritionnelles sur la production de surfactines par Bacillus amyloliquefaciens. Cette analyse se fait au travers de trois aspects : la diversité structurale des surfactines, la dynamique de production de celles-ci et leurs activités biologiques. Dans un premier temps, la comparaison de différents milieux de cultures a permis de sélectionner le milieu RE (« recomposed exudates ») comme milieu reproduisant suffisamment bien les conditions nutritionnelles de la rhizosphère. La diversité structurale a été analysée par UPLC-MS et a mis en évidence, en comparaison au milieu riche LB, la production supplémentaire de trois variants de surfactine lorsque B. amyloliquefaciens est cultivé en milieu RE. Des analyses UPLC-MS et une RT-qPCR ont permis de comparer la quantité de surfactines et l’expression des gènes associés à la biosynthèse de celles-ci en milieu RE et en milieu LB. L’activité biologique des surfactines produites en milieu RE a été évaluée via deux expérimentations : un test d’antagonisme sur deux phytopathogènes bactériens et un test ROS (« reactive oxygen species ») permettant d’estimer le pouvoir éliciteur des surfactines.

Bacillus amyloliquefaciens biocontrôle surfactine UPLC-MS RT-qPCR --- Sciences du vivant > Agriculture & agronomie

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Malgré les récentes régulations sur la production et l’utilisation de substances polyfluorées, ces composés persistants sont de nos jours ubiquitaires dans les milieux aquatiques, et ce même dans des endroits isolés tels les Iles Féroé.
Ce mémoire a pour but d’observer l’évolution de la contamination par 18 PFAS d’une population d’Ombles Chevaliers (Salvelinus Alpinus) d’un lac isolé situé sur l’île de Streymoy aux Iles Féroé. Ce lac est (à notre connaissance) exempt de toute contamination anthropogénique directe.
Les échantillons (muscles prélevés sur le filet droit) ont été analysés à l’aide d’une chromatographie en phase liquide et d’un spectromètre de masse.
Les résultats auraient du être mis en relation avec des données météorologiques du Landversk ; le transport par voie aérienne et les dépositions humides étant les voies de contaminations principales suspectées, ceci aurait pu permettre de voir si la contamination des poissons suit effectivement l’évolution des précipitations.
Les précipitations variant énormément d’un endroit à l’autre au sein des Iles Féroé, des échantillons d’eau ont été prélevés dans 9 lacs. Ceux-ci ont été concentrés et nettoyés via extraction en phase solide et auraient du être analysés par UPLC et MS. Les résultats auraient été mis en parallèle avec des données météo afin de voir si la contamination des lacs semble suivre les différents taux de précipitations.
Suite à un problème technique (une pompe de l’UPLC n’est plus fiable), les échantillons d’eau n’ont pas pu être analysés. Les analyses des échantillons de poissons sont quant à elles non fiables.
Les conclusions, basées sur des résultats non fiables, sont que les concentrations de PFAS étaient croissantes jusqu’à 2009 et semblent diminuer à partir de 2011. Aucune donnée météo n’était disponible jusqu’à 2006, et les données pour la période 2006-2009 se sont avérées inexploitables. Restent donc 2010 à 2014, mais les échantillons de poisson analysés datent de 2011 au plus tard ; les résultats n’ont donc pas pu être mis en lien. Despite the increasing number of regulations on the production and uses of polyfluorinated substances, those persistent compounds are nowadays ubiquitous in marine environments, even in remote places such as the Faroe Islands.
This master thesis aimed to establish a time trend of 18 different PFAS in a population of Arctic chars (Salvelinus Alpinus) from Lake á Mýrunum from 2000 until 2014. This small lake is located on the island of Streymoy and is isolated from direct anthropogenic contamination.
The fish samples (right filet muscle) were prepared specifically for this purpose and analysed using an Ultra Performance Liquid Chromatograph and a tandem mass spectrometer.
The results would then be put in relation with meteorological data from Landversk, as atmospheric transport and wet depositions are suspected to be the main source of PFAS in the Faroe Islands, especially in places as isolated as Lake á Mýrunum. This would have allowed seeing whether the evolution of PFAS contamination in fishes seems to follow the precipitations.
Since precipitations in the Faroe Islands vary greatly from a place to another, nine lake were sampled. Those samples werre prepared using Solid Phase Extraction and would have been analysed for PFAS contamination in the water. The results would have been related to meteorological data to see whether lake water contamination is directly dependent of rain.
Due to technical issues (a pump from the UPLC failed), no lake water samples were analysed, and most of the fish sample analyses failed.
The conclusions, based on unreliable results, are that PFAS’s concentration in fishes tend to increase until 2009 before starting to decrease in 2011. The meteo data turned out being unexploitable for the 2006-2009 period and the data from before 2006 could not be retrieved. The few results of the fish analyses could therefore not be related to the meteorological data.

substances polyfluorées (PFAS) --- dépositions humides --- PFOS/PFOSA --- Ultra Performance Liquid Chroamtography (UPLC) --- Spectrométrie de Masse (MS) --- Extraction en Phase Solide (SPE) --- alkyl substances (PFAS) --- wet depositions --- PFOS/PFOSA --- remote environment --- Ultra Performance Liquid Chroamtography (UPLC) --- Mass Spectrometry (MS) --- Solid Phase Extraction (SPE) --- Sciences du vivant > Sciences de l'environnement & écologie

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Phytotherapy is probably the oldest form of medicine; however, it represents a new therapeutic tool for healthcare workers. Indeed plants are an infinite source of novel molecules, with countless possible combinations. This collection of articles (a Special Issue from Molecules) brings together the most up-to-date studies on the use of plant-derived compounds, ranging from their anti-inflammatory, antioxidant, and anticancer effects to the revision of the prominent literature.

Medicine --- natural products --- phenylpropanoids --- phenolic acids --- plants --- depression --- behavioral disorders --- forced swim test --- tail suspension test --- anti-cancer activities --- multifloroside --- 10-oxyderivatives of oleoside secoiridoids --- structure-activity relationship --- flow cytometry --- epigallocatechin-3-gallate --- EGCG --- catechin --- green tea --- cancer preventive --- pharmacological activities --- Amelanchier alnifolia Nutt. --- carriers --- powders --- bioactive compounds --- functional food --- Ageratina havanensis --- flavonoids --- UPLC-ESI-MS/MS --- P-glycoprotein --- antioxidant potential --- nootkatone --- anti-inflammatory --- acute inflammation --- granuloma --- Pharbitis nil --- colorectal cancer --- KRAS --- muscle function --- juglone --- NLRP3 inflammasome --- caspase-1 --- IL-1β --- IL-18 --- plant secondary metabolites --- natural compounds --- biological activity --- phytochemistry --- pharmacological activity --- plant side effects --- Talisia esculenta --- Brosimum gaudichaudii --- Genipa americana --- Bromelia antiacantha --- RA-3 --- nephrotoxicity --- triterpene --- antioxidant --- hyperuricemia --- Hibiscus acetosella --- phenolic compound --- antibacterial --- UPLC --- Tabebuia impetiginosa --- Taheebo --- traditional uses --- immunopharmacology --- immunological disorders --- hesperidin --- new-clean process extraction --- nanocrystals --- anti-ageing --- zingerone --- lipopolysaccharide --- inflammation --- anti-oxidant --- cytokine storm --- procalcitonin --- histopathology --- doxorubicin --- Mahonia aquifolium --- matrix metalloproteinases --- cytotoxicity --- human lung adenocarcinoma --- n/a

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Throughout most of history, medicinal plants and their active metabolites have represented a valuable source of compounds used to prevent and to cure several diseases. Interest in natural compounds is still high as they represent a source of novel biologically/pharmacologically active compounds. Due to their high structural diversity and complexity, they are interesting structural scaffolds that can offer promising candidates for the study of new drugs, functional foods, and food additives.Plant extracts are a highly complex mixture of compounds and qualitative and quantitative analyses are necessary to ensure their quality. Furthermore, greener methods of extraction and analysis are needed today.This book is based on articles submitted for publication in the Special Issue entitled “Qualitative and Quantitative Analysis of Bioactive Natural Products” that collected original research and reviews on these topics.

Scorzonera --- capsaicinoids --- artificial neural network --- cerebral ischemia reperfusion injury --- antioxidant activity --- quality evaluation --- chemometrics --- secondary metabolites --- identification --- antioxidant capacity --- Moroccan region --- volatile compounds --- HPLC-Q-Exactive-Orbitrap-MS --- quantitative analysis --- amino acids content --- HPLC-ELSD --- antioxidant --- autophagy --- quantification --- sugars --- 1-triacontanol --- hemp seed oil --- Alzheimer’s disease --- macrodiolides --- extraction --- recycling preparative high performance liquid chromatography --- HPLC methods --- GC-MS --- Myristica fragrans --- Rossa da inverno sel. Rojo Duro onion cultivar --- fruit powders --- decursin --- food traceability --- ionic liquids --- separation optimisation --- Spondias spp. --- C-glycosylflavone --- wine --- UPLC-MS --- scutellarein --- saffron --- carotenoids --- red cabbage --- hydrodistillation --- Ginkgo biloba Extract (GBE) --- gas chromatography --- organic acids --- olive leaves --- crocins --- CBD oil --- Bolbostemma paniculatum --- UPLC-ESI-MS/MS --- geographical origin --- HPLC --- traditional Chinese medicine decoction --- liquid chromatography --- bioactive natural compounds --- Podospermum --- metabolic profiling --- SPME-GC/MS --- LTQ-Orbitrap --- oral administration --- UPLC --- bioactive compounds --- Erigeron breviscapus extract --- terrain conditions --- nutmeg --- antibacterial activity --- method validation --- ShenFu prescription decoction --- chili --- decursinol angelate --- statistical evaluations --- stereoselective and simultaneous analysis --- curcuminoids --- Talaromyces pinophilus --- talarodiolide --- HPLC-Q-TOF-MS/MS --- Olea europaea L. --- triterpenes --- chromatogram-bioactivity correlation --- essential oil --- stability --- Staphylococcus aureus --- Iris lactea Pall. var. chinensis (Fisch.) Koidz. --- endothelial function --- anthocyanins --- HPLC analysis --- liquid chromatography-mass spectrometry --- nodakenin --- turmerone --- UHPLC-MS/MS --- Quercus acuta leaf --- Curcuma longa --- UHPLC analysis --- ginseng berry extract --- geographical variation --- qualitative analysis --- Sorbus --- free radical-scavenging --- ginsenosides --- flavonoids --- biostimulant --- GC/MS --- terpenes --- aleuritolic acid --- phenolic compounds --- apoptosis --- response surface methodology --- phenolic acids --- pharmacokinetics --- mass spectrometry --- scutellarin --- multivariate statistical analysis --- phenolics --- MODDE experimental design --- proanthocyanidins --- UFLC-QQQ-MS --- rice --- cannabidiol --- odor-activity values --- UPLC-QTOF-MS --- turmeric --- decursinol

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Natural products or organic compounds isolated from natural sources as primary or secondary metabolites have inspired numerous drugs. It is not an overstatement that the majority of medicines in clinics, even in the 21st century, have been derived from natural resources despite the decline of industry research into natural products due to a variety of drawbacks. Saffron crocus, considered to be the most valuable spice by weight, and its bioactive constituents, have been studied for the treatment of a wide range of pathologies, including neuropsychiatric and neurodegenerative disorders, cancer, diabetes, and even cardiovascular diseases. In this book on the chemistry, pharmacology, and therapeutic potential of Crocus sativus L. extract and its constituents, we aimed to assess new advances in the understanding of the therapeutic action of saffron and its constituents in targeting different pathologies. In this context, eight original research articles covering recent advances in the therapeutic actions of saffron and its ingredients in different diseases are reported. Two studies reporting novel methods regarding the bioanalysis of saffron extracts have been included. The collection is completed with two very interesting reviews reporting advances in the fields of schizophrenia and cancer. In conclusion, in this book, we are delighted to have received several contributions that we hope will provide new and interesting information for the scientific community on the chemistry, pharmacology, and therapeutic potential of Crocus sativus L. extract and its constituents.

saffron --- affron® --- depression --- anxiety --- antioxidant --- crocins --- glucose --- β-pancreatic cells --- insulin --- pck1 --- neuroprotective activity --- P2X7 receptor --- fraction --- flumazenil --- rat --- Crocus sativus --- cancer --- anticancer activity --- chemoprevention --- clinical trials --- patents --- anesthetic ketamine --- memory --- Crocus sativus L. --- schizophrenia --- crocetin --- pubertal testis --- X-rays --- radiotherapy --- fertility preservation --- SIRT1 --- HuR --- oxidative stress --- autophagy --- crocin --- picrocrocin --- safranal --- dietary supplement --- nutraceutical --- Crocus sativus L. (Iridaceae) --- reversed-phase UPLC --- metabolomics --- HR MS --- inflammatory bowel disease --- gut microbiota --- colitis --- cytokines --- colorectal cancer --- HCT116 --- MLH1 --- MSH3 --- DNA damage and repair --- apoptosis --- n/a