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This thesis was carried out at the Laboratory of Pharmacognosy and the Laboratory of Pharmaceutical technology, at the UFR Sciences de Santé, circonscription Pharmacy, in the University of Burgundy Franche-Comté, to find new natural molecules to encapsulate. First of all, we focused on the natural saponins from plants of the Vietnam biodiversity and the french horticulture, belonging to the three genera Dracaena, Cordyline (Asparagaceae) and Weigela (Caprifoliaceae). The work led to the successful isolation and elucidation of 42 natural saponins using various chromatographic techniques. The structures were determined by ESI mass spectrometry and NMR spectroscopy. Among the 17 pure compounds obtained from three species of the Weigela genus, 9 oleanolic acid and hederagenin glycosides are previously undescribed ones. From the two species Dracaena braunii and Cordyline fruticosa “Fairchild red”, we isolated and characterized 18 steroidal saponins including 7 new spirostane-types and 6 new furostane-types ones. The cytotoxic activities of the majority of isolated saponins were evaluated against mouse colon cancer (CT26 cells), mouse melanoma (B16 cells) and human liver cancer (HepG2 cells) by MTS assays. The structure / activity relationships were also proposed.On the other hand, we selected a well-known natural molecule to develop encaspulation tests. Among the natural products, curcumin has very interesting therapeutic properties but exhibits both a poor solubility and a low bioavailability, limiting the administration by the oral route. The purpose of this study was to improve the solubility and bioavailability of curcumin as well as simultaneously achieve controlled release in gastrointestinal tract. Pectinate gel beads were prepared based on ionotropic gelation method with the presence of vaious surfactants. After drying, these beads were investigated for physicochemical characteristics (morphological aspects, encapsulation efficiency, stability, physical state) and dissolution kinetics (in vitro release). Antioxidant activity was also determined with DPPH assay. Kolliphor HS15® seems to be the best promising surfactant to increase stability and bioavailability of curcumin., Cette thèse s’inscrit dans la cadre de la thématique du Laboratoire de Pharmacognosie et du Laboratoire de Pharmacie Galénique de l’UFR Sciences de Santé, circonscription Pharmacie, au sein de l’Université de Bourgogne Franche-Comté, afin de trouver de nouvelles molécules naturelles bioactives à encapsuler. D’une part, nous nous sommes concentrés sur la recherche de saponines naturelles de plantes issues de la biodiversité vietnamienne et de l’horticulture française du genres Dracaena, Cordyline (Asparagaceae) et Weigela (Caprifoliaceae). Les travaux menés ont conduit à isolement de 42 saponines naturelles en utilisant différentes techniques chromatographiques. Les structures on été déterminées par des méthodes de spectrométrie de masse en source ESI et de spectroscopie RMN. Parmi les 17 composés purs obtenus des 3 espèces appartenant au genre Weigela, 9 sont des glycosides de l’acide oléanolique et de l’hédéragénine de structure nouvelle. A partir des espèces Dracaena braunii et Cordyline fruticosa “Fairchild red”, nous avons isolé et caractérisé 18 saponines stéroïdiques dont 7 nouvelles de type spirostane et 6 nouvelles de type furostane. Les activités cytotoxiques de la majorité des saponines isolées ont été évaluées sur trois lignées cellulaires : CT26 (cellules tumorales coliques murines), B16 (cellules de mélanome murin) et HepG2 (cellules d’hépatocarcinome) par le test de prolifération cellulaire MTS. Des relations structure/ activité ont ainsi été proposées.D’autre part, nous avons sélectionné une molécule naturelle bien connue afin de mettre au point les essais d’encapsulation. La curcumine possède des propriétés thérapeutiques très intéressantes mais elle présente à la fois une faible solubilité et une faible biodisponibilité, limitant l'administration par voie orale. Dans cette partie de la thèse, nous avons cherché à améliorer la stabilité et la biodisponibilité de la curcumine ainsi qu’une libération contrôlée dans le tractus gastro-intestinal. Des billes de pectinate de calcium ont été préparées en utilisant la gélification ionique en présence de différents tensioactifs. Elles ont été caractérisées grâce à leurs propriétés physico-chimiques et leurs profils de dissolution in vitro. Leur activité antioxydante a été évaluée par le test DPPH. Le Kolliphor HS15® est le tensioactif le plus prometteur pour optimiser les propriétés de la curcumine.

International audience; Scope : It is widely advised to increase pulse consumption. However, pulses are rich in molecules displaying lipid‐lowering properties, including fibers, phytates, saponins and tannins. We thus explored the effects of pulses on fat‐soluble vitamin bioavailability. Methods : We assessed vitamin A (β‐carotene and retinyl‐palmitate), vitamin E (α‐tocopherol), vitamin D (cholecalciferol) and vitamin K (phylloquinone) bioaccessibility, i.e. micellarization after in vitro digestion of meals containing either potatoes (control), household‐cooked or canned pulses. The obtained mixed micelles were delivered to Caco‐2 cells to evaluate vitamin uptake. We then specifically assessed the impact of fibers, phytates, saponins and tannins on both phylloquinone (used as a model vitamin) bioaccessibility and uptake. Results : The presence of pulses significantly decreased both vitamin bioaccessibility (up to ‐65% for β‐carotene, ‐69% for retinyl‐palmitate, ‐45% for cholecalciferol, ‐53% for α‐tocopherol and ‐67% for phylloquinone) and uptake (‐40% for retinyl‐palmitate, ‐67% for cholecalciferol, ‐50% for α‐tocopherol and ‐57% for phylloquinone). Effects on bioaccessibility, but not on uptake, were dependent on pulse cooking method. Phylloquinone bioaccessibility was specifically impacted by saponins, tannins and fibers while its uptake was impacted by saponins, fibers and phytates. Conclusion : Pulses can alter fat‐soluble micronutrient bioavailability. Pulses should thus be cooked appropriately and consumed within micronutrient‐rich meals.

ISBN 0-8133-7071-X ; 45 ref.

Wild yams (Dioscorea spp.) are medicinal plants rich in secondary metabolites of pharmacological interest, mostly allantoin and steroidal saponins. Their natural populations are overexploited and endangered. Cultivated yams could represent an alternative source of metabolites if interesting varieties could be selected. The objectives of the present study were to develop an HPTLC protocol for the simultaneous quantification of allantoin and steroidal saponins in dried yam powders, to compare species and varieties originating from distant geographical origins and to assess their potential as a source of secondary metabolites. Overall, 1151 accessions belonging to six cultivated species were analysed (1000 acc. from Nigeria, and 146 acc. from Vanuatu) and were compared to five commercial powders of wild yam (D. villosa). Allantoin, dioscin, gracillin, protodioscin, protogracillin and five unknown saponins were quantified. Dioscorea villosa powders varied in content and composition, with allantoin ranging from 0.23 to 22.35 mg/g (DW) and total saponins from 37.36 to 129.97 mg/g. Allantoin was present in the six species, with highest values in D. bulbifera bulbils (20.38 mg/g) and D. cayenensis tubers (17.12 mg/g). Steroidal saponins were quantified in three species, D. cayenensis, D. esculenta and D. rotundata, but were absent in D. alata, D. bulbifera and D. dumetorum. Mean total saponins contents were 42.15 mg/g in D. cayenensis, 17.65 mg/g in D. esculenta and 17/44 mg/g in D. rotundata, with accessions presenting very high values in D. cayenensis (78.31 mg/g) and D. rotundata (69.65 mg/g). For both allantoin and saponins, variation was observed within tubers and the tuber peel was richer than the flesh. Cultivated yam species represent a sustainable source of allantoin and steroidal saponins which could be further increased through conventional breeding.

Die Resistenz von kommensalen Bakterien gegenüber Standard- und Reserveantibiotika hat in vielen Teilen der Welt ein beängstigendes Ausmaß erreicht und stellt zunehmend eine Gefahr für den Erfolg antibiotischer Behandlungen dar. Insbesondere Infektionen mit den Bakterienarten Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterococcus faecium (VRE) und Staphylococcus aureus (MRSA), welche zu den Erregern von Wundinfektionen zählen und eine Vielzahl von Antibiotikaresistenzen aufweisen können, führen im klinischen Umfeld zunehmend zu Problemen. In Anbetracht des Mangels an verfügbaren neuen Antibiotika, eröffnet die Entwicklung von Resistenz modifizierenden Substanzen eine Perspektive um die Verbreitung von Antibiotikaresistenzen einzudämmen und die Verwendung zugelassener Antibiotika, gegen die Resistenzen auftreten, weiterhin zu ermöglichen. In dieser Arbeit wurde der Einfluss von pflanzlichen Extrakten und Einzelsubstanzen auf die Resistenz von klinischen Isolaten der oben erwähnten Bakterienarten gegenüber den Antibiotika Ampicillin, Piperacillin, Imipenem, Gentamicin, Vancomycin und Aztreonam untersucht. Die methanolischen und wässrigen Extrakte sowie die Einzelsubstanzen stammen unter anderem von Achillea millefolium, Arctostaphylos uva-ursi, Cetraria islandica, Glycyrrhiza glabra, Lythrum salicaria, Plantago lanceolata, Salvia officinalis, Solidago virgaurea und Thymus vulgaris. Für alle diese Pflanzen ist eine historische Verwendung zur Wundbehandlung belegt. Um mögliche synergistische Wechselwirkungen zwischen den Antibiotika und den Naturstoffen zu identifizieren wurden die Kombinationen mit der checkerboard-Methode analysiert. Von den 160 Kombinationen von Antibiotika und Extrakten aus acht verschiedenen Pflanzen, zeigten 30 Kombinationen Werte für den fraktionierten inhibitorischen Konzentrationsindex (FICI) von ≤0,5, was ein Nachweis für eine synergistische Wechselwirkung ist. Die meisten Synergien traten bei den gram positiven Erregern VRE und MRSA auf, hauptsächlich in Kombination mit Ampicillin und Gentamicin. Bei Klebsiella pneumoniae erwies sich keine Kombination als synergistisch und bei Pseudomonas aeruginosa traten Synergien nur mit Ampicillin, Piperacillin und Vancomycin auf. Die stärksten synergistischen Wechselwirkungen zeigten sich an den Enterokokken mit den Kombinationen von Urolithin A mit Ampicillin (FICI: ≤0,0002), Glycyrrhizinsäure mit Gentamicin (FICI: 0,018) sowie dem methanolischen Extrakt von Cetraria islandica mit Gentamicin (FICI: 0,05). Die Ergebnisse dieser Arbeit deuten auf ein therapeutisches Potential von Naturstoffen als Kombinationspartner von Antibiotika bei der Behandlung von Wundinfektionen mit multiresistenten Bakterien hin., The resistance of commensal bacteria to first- and second-line antibiotics has reached an alarming level in many parts of the world and endangers the effective treatment of infectious diseases. Particularly Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterococcus faecium (VRE) and Staphylococcus aureus (MRSA), which may exhibit a broad resistance to various antibiotics and be involved in wound infections, represent an increasing clinical problem in the treatment of infectious diseases and hinder adequate antibiotic stewardship. Considering the lack of novel antibiotic compounds, the development of resistance-modifying agents, however, can mitigate the spread of bacterial drug resistance and might possibly extend the useful application indices of an existing licensed antibiotic. In this thesis, the influence of herbal extracts and pure substances on the susceptibility of clinical isolates of the bacteria mentioned above against the antibiotics ampicillin, piperacillin, imipenem, gentamicin, vancomycin and aztreonam was investigated. Furthermore, the antibacterial properties of the natural substances under study were determined in vitro. The plants from which the methanolic and aqueous extracts and pure substances originated were among others Achillea millefolium, Arctostaphylos uva-ursi, Cetraria islandica, Glycyrrhiza glabra, Lythrum salicaria, Plantago lanceolata, Salvia officinalis, Solidago virgaurea and Thymus vulgaris. For all these plants the historical use in wound infections has been proven. The combined effects of antibiotics and natural substances were determined with the checkerboard method to estimate a possible synergy. Out of 160 investigated combinations with eight plant extracts, 30 showed a synergistic interaction, with FICI values of ≤0. 5, which indicates synergy. Most synergistic interactions occurred with the gram-positive pathogens VRE and MRSA, mostly with ampicillin and gentamicin. Klebsiella pneumoniae showed no synergy with any combination and Pseudomonas aeruginosa only with ampicillin, piperacillin and vancomycin. The strongest synergistic interactions were observed in enterococci with the combination of urolithin A with ampicillin (FICI: ≤0.0002), of glycyrrhizic acid with gentamicin (FICI: 0.018) and of the methanolic extract of Cetraria islandica with gentamicin (FICI: 0.05). In conclusion, this thesis points towards a therapeutic potential of natural substances in co-application with antibiotics for defined local bacterial infections caused by antibiotic resistant bacteria.

Licence; Au cours des dernières années, les protéines végétales ont pris de plus en plus de place pour substituer partiellement les protéines animales. En effet, de récentes recommandations préconisent une réduction des protéines provenant de sources animales en raison de préoccupations environnementales. Les poudres de protéines de pommes de terre peuvent, par exemple, être utilisées pour remplacer des blancs d’oeufs. En effet, elles peuvent permettre grâce à leurs propriétés moussantes de réaliser des recettes adaptées à une alimentation végétarienne, voir vegan. Cependant, ces protéines végétales peuvent contenir des molécules indésirables qui peuvent modifier les propriétés de ces protéines. Parmi ces constituants, nous trouvons les saponines. Les saponines peuvent être toxiques pour la santé si elles sont ingérées en grande quantité (2-5mg par 1kg de masse corporelle). Par conséquent, des techniques de détection et de quantification des saponines dans des extraits protéiques végétaux est nécessaire. Ce stage portait donc sur la mise au point de ces méthodes de détection et de quantification de saponines dans des poudres de protéines de pommes de terre commercialisées et dans des pommes de terre fraîches. Les résultats obtenus avec les analyses d’échantillons par la chromatographie liquide à haute performance en phase inverse ont montré que les poudres de protéines de pommes de terre commercialisées respectent bien la législation (300mg de saponines par kilogramme de poudre). De plus, les résultats apportés par cette même méthode et par la chromatographie sur couche mince ont permis de confirmer la présence de saponines qui peuvent être extraites de pommes de terre fraîches.

Pulses display nutritional benefits and are recommended in sustainable diets. Indeed, they are rich in proteins and fibers, and can contain variable amounts of micronutrients. However, pulses also contain bioactive compounds such as phytates, saponins, or polyphenols/tannins that can exhibit ambivalent nutritional properties depending on their amount in the diet. We characterized the nutritional composition and bioactive compound content of five types of prepared pulses frequently consumed in France (kidney beans, white beans, chickpeas, brown and green lentils, flageolets), and specifically compared the effects of household cooking vs. canning on the composition of pulses that can be consumed one way or the other. The contents in macro-, micronutrients, and bioactive compounds highly varied from one pulse to another (i.e., 6.9 to 9.7 g/100 g of cooked product for proteins, 4.6 to 818.9 &micro, g/100 g for lutein or 15.0 to 284.3 mg/100 g for polyphenols). The preparation method was a key factor governing pulse final nutritional composition in hydrophilic compounds, depending on pulse species. Canning led to a greater decrease in proteins, total dietary fibers, magnesium or phytate contents compared to household cooking (i.e., &minus, 30%, &minus, 44%, &minus, 33% and &minus, 38%, p &lt, 0.05, respectively, in kidney beans). As canned pulses are easy to use for consumers, additional research is needed to improve their transformation process to further optimize their nutritional quality.

Dietary supplementation with linseed, saponins and nitrate is a promising methane mitigation strategy in ruminant production. The main objective of this work was to assess the effects of these additives on the rumen microbiota in order to understand underlying microbial mechanisms of methane abatement. Two 2 × 2 factorial design studies were conducted simultaneously, which also allowed us to make a broad-based assessment of microbial responses. Eight non-lactating cows were fed diets supplemented with linseed or saponin in order to decrease hydrogen production and nitrate to deviate hydrogen consumption; also, combinations of linseed plus nitrate or saponin plus nitrate were used to explore the interaction between dietary treatments. Amplicon sequencing of 18S and 16S rRNA genes was employed to characterise rumen microbes. Nitrate fed alone or in combination in both studies dramatically affected the composition and structure of rumen microbiota, though impacts were more evident in one of the studies. Linseed moderately modified bacterial community structure with no effect on rumen methanogens and protozoa. Indicator OTU analysis revealed that both linseed and nitrate reduced the relative abundance of hydrogen-producingRuminococcaceae. Linseed increased the proportion of bacteria known to reduce succinate to propionate, whereas nitrate supplementation increased nitrate-reducing bacteria and decreased the metabolic activity of rumen methanogens. Saponins had no effect on the microbiota. Inconsistency found between the two studies, when nitrate was fed to the cows could be explained by changes in microbial ecosystem functioning rather than changes in microbial community structure.ImportanceThis study aimed at identifying the microbial mechanisms of enteric methane mitigation when linseed, nitrate and saponins were fed to non-lactating cows alone or in a combination. Hydrogen is a limiting factor in rumen methanogenesis. We hypothesised that linseed and saponins would affect hydrogen producers and nitrate would deviate hydrogen consumption thus leading to reduced methane production in the rumen. Contrary to what was foreseen, both linseed and nitrate had a deleterious effect on hydrogen producers; linseed also redirected hydrogen consumption towards propionate production, whereas nitrate stimulated the growth of nitrate reducing and hence hydrogen-consuming bacterial taxa. Fundamental knowledge of microbial mechanism involved in rumen methanogenesis, provides novel insights for the development of new or the optimisation of existing methane mitigation strategies.

The ability of specific triterpenoid saponins to act as a novel mediator of the endosomal release was investigated thoroughly in the past. By interacting with the endosomal membrane, these sec-ondary plant metabolites from Saponaria- or Gypsophila-specimen are able to release the endo-somal or lysosomal content before being degraded by lysosomal enzymes. Special attention hereby was paid to the use of ribosome-inactivating proteins, which can induce the apoptotic cell death by cleaving an adenine out of the 28S-Subunit of the ribosomes. A synergy between triterpenoid saponins and RIPs achieved an amplified cell toxicity in several studies, which was even tested successfully in many in-vivo-studies. Resulting out of a less specific release from the endosomes, a logic consequence was to test the ability of the triterpenoid saponins in other scien-tific fields. Therefore, the quest of this work happened to be the investigation of the saponin me-diated enhanced gene delivery (transfection). For this purpose, a number of different nanocarriers were formulated and analyzed for their suitability as stable nanoplexes in terms of size, zetapotential, uniformity, stability and DNA-complexation efficiency. After the establishment of a robust transfection method with peptide-based nanoplexes, a number of different saponins could be tested on their transfection enhancing properties, among them SO1861, isolated from Saponaria officinalis L., and GE1741, isolated from Gypsophila elegans M.Bieb. In addition, a further breakdown of the structure-activity relationship regarding the endosomal release could be achieved. After the identification of the highly active saponins SO1861 and GE1741, not only the transfection efficiency, but also the universal applicability was investigated. A flexible as-signment could be demonstrated in different cell lines, transfection methods as well as with dif-ferent nucleic acids. The fact of a not elucidated mechanism of the modulated endosomal escape was a further topic of this work. By applying microscopic and fluorescence-based methods, val-uable insights regarding the intracellular uptake and release could be gathered. With the transfec-tion of a RIP-gene the opportunity of a concrete therapeutic application was investigated. Initial in-vitro-tests confirmed a non-toxic reporter gene delivery as well as an effective and highly toxic suicide gene delivery. On neuroblastoma bearing NMRI nu/nu mice, finally an in-vivo-efficacy was demonstrated, after the combined application of SO1861 and targeted YD-nanocarrier (suicide gene) led to a 50% decrease of tumor growth. In this work, for the first time the big potential of specific triterpenoid saponins as potent trans-fection enhancer could be described. Despite detailed investigations and connected with that, an establishment of a sound basis, a further breakdown of the mechanistic actions and precise opti-mizations are highly necessary in order to manifest a big value of saponins in future gene and cancer therapies., Die Fähigkeit bestimmter Triterpensaponine als Mediator des endosomalen Release zu agieren, wurde in der Vergangenheit intensiv beforscht. Durch Interaktion mit der Endosomenmembran sind diese Sekundärstoffe aus u.a. Saponaria- oder Gypsophila-Arten in der Lage, den endoso-malen Inhalt vor dem lysosomalen Abbau aus den späten Endosomen oder Lysosomen zu befrei-en. Ein besonderes Interesse galt dabei dem Einsatz von Ribosomen-inaktivierenden Proteinen, die durch enzymatische Abspaltung eines Adenins aus der 28S-Unterheit der Ribosomen den apoptotischen Zelltod induzieren. Ein Synergismus zwischen den Triterpensaponine und RIPs verzeichnete in zahlreichen Experimenten eine vervielfachte Zytotoxizität, die gar in vielen in-vivo-Studien erfolgreich getestet wurde. Aus der weniger spezifischen Freigabe aus den Endo-somen resultierend, war es lediglich eine logische Konsequenz, die Fähigkeit der Triterpensa-ponine an weiteren Gebieten zu testen. So wurde es in dieser Arbeit zur Aufgabe, die Möglich-keiten eines durch Saponine verstärkten Gentransfers (Transfektion) zu testen. Für diesen Zweck wurden zunächst eine Reihe verschiedener Nanocarrier formuliert und durch ihre Größe, Zetapotential, Uniformität, Stabilität sowie DNA-Komplexierungseffizienz hinsicht-lich ihrer Eignung als stabile Nanoplexe analysiert. Nach der Etablierung einer robusten Trans-fektionsmethode mit peptidbasierten Nanoplexen konnte eine Vielzahl verschiedener Saponine auf ihre transfektionsverstärkenden Eigenschaften getestet werden. Darunter gehörten unter an-derem das aus Saponaria officinalis L. isolierte SO1861 und aus Gypsophila elegans M.Bieb. isolierte GE1741. Mithilfe der Screenings konnte zudem eine weitere Aufschlüsselung der bisher beschriebenen Struktur-Wirkungs-Beziehung bezüglich des endosomalen Release erreicht wer-den. Mit der Identifizierung der hochpotenten Saponine SO1861 und GE1741 wurden nicht nur die Transfektionseffizienz, sondern gleichermaßen die universellen Anwendungsmöglichkeiten untersucht. Dabei wurde ein flexibler Einsatz der Saponine hinsichtlich verschiedener Zelllinien, verschiedener Transfektionsmethoden oder gar verschiedener Nukleinsäuren demonstriert. Die Tatsache eines bisher nicht aufgeklärten Mechanismus des modulierten endosomalen Release war ferner Gegenstand dieser Arbeit. Anhand diverser mikroskopischen oder fluoreszenzbasierten Methoden konnten wertvolle Erkenntnisse hinsichtlich der intrazellulären Aufnahme sowie Freigabe gewonnen werden. Mit der Transfektion eines RIP-Gens wurde eine neue Methode der nicht viralen Tumor-Gentherapie demonstriert, sowie die Möglichkeit einer konkreten therapeutischen Anwendung erstmalig ergründet. Initiale in-vitro-Tests bestätigten hierbei einen nicht toxischen Reporter-Gentransfer sowie einen effektiven und hochtoxischen Suizid-Gentransfer. An NMRI nu/nu-Mäusen mit beimpftem Neuroblastoma wurde schließlich zum ersten Mal durch eine saponin-vermittelte in-vivo-Gentherapie eine Wirksamkeit demonstriert, nachdem durch eine kombinierte Gabe von SO1861 und gerichteten YD-Nanocarriern (Suizidgen) eine 50%ige Tumorwachs-tumshemmung beobachtet worden war. In dieser Arbeit konnte somit erstmals das große Potential spezifischer Triterpensaponine als potente Transfektionsverstärker beschrieben werden. Trotz der umfassenden Untersuchungen und der damit verbundenen Erstellung einer fundierten Wissensgrundlage ist eine weitere Erfor-schung der beschriebenen Anwendung jedoch dringend notwendig. Eine weitere Entschlüsselung der genauen mechanistischen Vorgänge sowie präzise Optimierungsschritte sind von ungemeiner Wichtigkeit, um einen hohen Wert für die zukünftige Gen- und Krebstherapie zu manifestieren.

The peri-partum period is a critical time for small ruminants because nutritional requirements are very high and feed intake is often limited. Nutritional diseases, such as pregnancy toxemia, can develop. Farmers try to limit these problems. β-glucan and saponin-based plant extracts have been shown to have favourable effects on animal production: immune-modulation for the former and reduced methane production and modification of rumen fermentation patterns for the latter. However, little is known about their effects on metabolism. Therefore, the general objective was to better understand the effects of 1) β-glucan injections and 2) dietary saponin, on metabolism and rumen fermentation in small ruminants during the transition period. The influence of β1,3-glucan (i.m. injections, 1ml/animal/week for 60 days) on the metabolic profile of 14 Santa Inês ewes in the last weeks of gestation was studied. Two groups of ewes were formed in late gestation: a glucan group (G, n=7) and a control group (C, n=7). Nutritional requirements during the experiment were covered. Blood samples were collected throughout the study. Blood samples were analysed for metabolites, ions and enzymes. All ewes were clinically healthy. Glucose, L-lactate, non-esterified fatty acids and β-hydroxybutyrate peaked at parturition (p0.05). The ruminal acetate to propionate ratio tended to be affected by treatment (S < C; p=0.057). There was no effect of saponin in experiment 2 on blood metabolites (p>0.05), except for plasma urea (S > C; p=0.054). Total protozoa numbers tended to be affected by treatment (S > C; p0,05). Le rapport acétate/propionate du rumen a eu tendance à être réduit (S 0,05), sauf pour l’urémie (S>C; p=0,054). Le nombre total de protozoaires a eu tendance à être augmenté (S>C, p

The effect of tea saponin supplementation in the ruminant diet on methane emissions, rumen fermentation, and digestive processes is still under debate. The objective of this study was to assess the effect of this plant extract on methanogenesis, total-tract digestibility, and lactating performances of dairy cows. The work included 2 independent and successive experiments. First, the effect of 7 tea saponin doses (from 0 to 0.50 g/L) on methane emissions and protozoa concentrations was tested in 2 repeated in vitro batch culture incubations using bovine rumen contents as inoculum and a cereal mixture as substrate. After 18 h of incubation, total gas production and composition as well as rumen fermentation parameters and protozoa concentration were analyzed. Increasing dosage of the plant extract reduced methane production and protozoa concentration, with a maximum reduction of 29% for CH4 (mL/g of substrate) and 51% for protozoa (10(5)/mL). Tea saponin did not affect volatile fatty acids concentration, but marginally decreased total gas production by 5% at the highest dose. Second, a 2-period crossover design experiment was carried out with 8 lactating dairy cows fed a basal diet (54% corn silage, 6% hay, and 40% pelleted concentrates on a dry matter basis) without (control) or with 0.52% tea saponin (TSP). Each experimental period lasted 5 wk. Animals were fed ad libitum during the first 3 wk of the period (wk 1, 2, and 3) and restricted (95% of ad libitum intake) during the last 2 wk (wk 4 and 5). Intake and milk production were recorded daily. Methane emissions were quantified using open chambers (2 d, wk 4). Total-tract digestibility and nitrogen balance were determined from total feces and urine collected separately (5 d, wk 5). Rumen fermentation parameters and protozoa concentration were analyzed from samples taken after morning feeding (1 d, wk 5). Milk production, dry matter intake, and feed-efficiency were reduced with TSP (-18, -12, and -8%, respectively). As daily methane production (g/d) was not affected, methane emissions (g/kg of dry matter intake) increased by 14% with TSP. Total-tract digestibility and nitrogen balance were similar between diets, except for acid detergent fiber digestibility, which tended to be improved with TSP (+4 percentage units). Rumen fermentation parameters and protozoa concentration were relatively unchanged by diets. Under the conditions of this experiment, tea saponin is not efficient to reduce methane emissions from dairy cows.

Clidemia hirta L., a tropical shrub used for traditional medicine in numerous countries, could constitute a new resource of phytochemicals for cosmetic applications. In vitro micropropagation of C. hirta was used to evaluate the influence of different culture media on plant growth, production of phytochemicals, and the antioxidant and antibacterial properties of leaf extracts. Quoirin and Lepoivre medium and Lloyd and McCown's woody plant medium gave the best results. Both production of phytochemicals (i.e., flavonoids, phenolics and saponins) and biological activities were affected by the culture medium composition with the strongest effects for plants cultivated on Quoirin and Lepoivre medium. Strong correlations were shown between the antibacterial activity and the saponin content and between the antioxidant capacity and the flavonoid content. The present study shows how mineral nutrition influences the production of secondary metabolites in C. hirta, thus modulating the biological activities of extracts with a view to their possible use in the cosmetic industry., Clidemia hirta L., un arbuste tropical utilisé en médecine traditionnelle dans de nombreux pays, pourrait constituer une ressource intéressante pour des applications cosmétiques. La micropropagation de C. hirta in vitro a été utilisée pour évaluer l'influence des milieux de culture sur la croissance des plantes ainsi que le contenu phytochimique et les activités antioxydantes et antibactériennes des extraits de leurs feuilles. Le milieu Quoirin et Lepoivre et le milieu Llyod et Mc Cown donnent les meilleurs résultats. Tant les contenus en flavonoïdes, composés phénoliques et saponines que les activités biologiques sont affectés par la composition du milieu, les meilleures valeurs étant obtenues avec le milieu Quoirin et Lepoivre. Des corrélations fortes sont observées entre activité antibactérienne et contenu en saponines, ainsi qu'entre capacité antioxydante et contenu en flavonoïdes. Cette étude montre l'influence de la nutrition minérale sur la production de métabolites secondaires chez C. hirta et son effet sur les activités des extraits qui peuvent en être dérivés pour une utilisation en cosmétique.

The term saponin comes from the Latin word sapo, meaning "soap", reflecting a readiness to form stable soap-like foams in aqueous solutions. The biological role of saponins is not completely understood, but they are generally considered to be part of a plant's defence system against pathogens and herbivores, particularly because of their bitter flavour. Saponins comprise aglycones and sugar, each representing about 50% of the total weight of the molecule. In quinoa, saponins are a complex mixture of triterpene glycosides that derive from seven aglycones: oleanolic acid, hederagenin, phytolaccagenic acid, serjanic acid, 3?-hydroxy-23-oxo-olean-12-en-28- oic acid, 3?-hydroxy-27-oxo-olean-12-en-28-oic acid and 3?,23?,30?-trihydroxy-olean-12-en-28-oic acid, while the most common sugars are arabinose, glucose and galactose. Saponins are traditionally considered very antinutritional because of their haemolytic activity, and there is therefore a longstanding controversy about their functions in food. It is believed that saponins can form complexes with membrane sterols of the erythrocyte, causing an increase in permeability and a subsequent loss of haemoglobin. However, recent extensive studies of the biological activity of saponins in vitro and in vivo have identified associations with several health benefits, including anti-inflammatory, anticarcinogenic, antibacterial, antifungal and antiviral effects. Saponins are also of interest as valuable adjuvants and the first saponin-based vaccines have been introduced commercially. Traditionally, quinoa seeds are either abraded mechanically to remove the bran - which is where the saponins are predominantly located - or washed with water to remove bitterness prior to use. During washing, valuable nutrients are lost and the chemical composition and amino acid profiles of quinoa seeds can be altered. Following treatment, the level of saponin content in to-be-consumed quinoa seeds remains a major concern in terms of bitterness and possible negative biological effects. A mathematical model based on Fick's second law has been created to optimize the leaching process of saponins from quinoa seeds during washing with water. Many studies have focused on the effects of agronomic variables (e.g. irrigation and salinity) on the saponin profiles of quinoa. It has been observed that saponins decrease in samples that have been exposed to drought and saline regimes - suggesting that irrigation and salinity may regulate the saponin content in quinoa and affect its nutritional and industrial values. Studies are underway to evaluate and compare the saponin content in seven varieties of quinoa grown in Italy and six varieties grown in Chile under rainfed or low irrigation conditions. Seeds from the more arid or stressing Chilean localities have a higher saponin content.