Academic literature on the topic 'Phytochemistry; Secondary metabolites'

Genus Pandanus belongs to the family Padanaceae, which is widely distributed in old world tropics and subtropics, and has been applied in traditional herbal medicines, pharmacological uses, food chemical products and handicrafts. Original research articles related to this genus are available but an insight account highlighted phytochemical aspects of secondary metabolites is now insufficient. The reliable sources of literature data for this systematic manuscript were obtained from the literatures published from 1960s to now, utilizing data information from ACS journals, Taylor Francis, Springer, IOP Science, SCI-finder, Chemical Abstracts, the Web of Science, Scopus, ScienceDirect, PubMed and Googlescholar. A vast amount of data showed that genus Pandanus contained various classes of the secondary metabolites. Herein, approximately 180 constituents were isolated, comprising alkaloids, phenols, lignans, steroids, terpenoids, lipids, flavonoids, coumarins, lactones and amino acids. In addition, the crucial information involved in food chemistry suggests that Pandanus species can also be a good candidate to provide essential oils and nutrient contents of vitamins and sugars.

The Brazilian Amazon rainforest, even for its richness and biological diversity, can offer the oppotunity for innovative and efficient discovery of molecules with potential use in large scale. The interest in secondary metabolites have grown tremendously in recent amazonian essential oils and plant extracts, the Maytenus guianensis is a shrub native to our region, being popularly known as fruit-werewolf. The leaves are used as anti-inflammatory and infections is also indicated in the treatment of arthritis and hemorrhoids. Thus, the present study aimed to identify the classes of secondary metabolites from the ethanol extract of the fruits, leaves and shell of M. guianensis. We carried out the identification of secondary metabolites with plant extract using specific reagents alkaloids, glycosides cardiotonic, coumarins, flavonoids, tannins, saponins and triterpenes, based on coloration and precipitation. It was found that all the studied structures show botanical alkaloids, coumarins, flavonoids and tannins using any specific reagents. However, the absence of a secondary metabolite which can serve as raw material for synthesis of bioactive substances, particularly drugs and are used in many preparations to benefit human health, such as in the production of food and biological activity against microrganisms.

Black ginseng is a type of processed ginseng that is prepared from white or red ginseng by steaming and drying several times. This process causes extensive changes in types and amounts of secondary metabolites. The chief secondary metabolites in ginseng are ginsenosides (dammarane-type triterpene saponins), which transform into less polar ginsenosides in black ginseng by steaming. In addition, apparent changes happen to other secondary metabolites such as the increase in the contents of phenolic compounds, reducing sugars and acidic polysaccharides in addition to the decrease in concentrations of free amino acids and total polysaccharides. Furthermore, the presence of some Maillard reaction products like maltol was also engaged. These obvious chemical changes were associated with a noticeable superiority for black ginseng over white and red ginseng in most of the comparative biological studies. This review article is an attempt to illustrate different methods of preparation of black ginseng, major chemical changes of saponins and other constituents after steaming as well as the reported biological activities of black ginseng, its major saponins and other metabolites.

Eichhornia crassipes (Mart.) Solms (Waterhyacinth), an aquatic perennial herb present throughout the world, has a myriad of metabolites. Phenalenone compounds and sterols have been isolated from this plant. Extracts, as well as pure compounds isolated from this plant, have been demonstrated to possess pharmacological activities. An account of the phytochemistry, pharmacological activities and several applications of waterhyacinth are included in this review.

As a genus of the Asteraceae, Inula is widely distributed all over the world, and several of them are being used in traditional medicines. A number of metabolites were isolated from Inula species, and some of these have shown to possess ranges of pharmacological activities. The genus Inula contains abundant sesquiterpenoids, such as eudesmanes, xanthanes, and sesquiterpenoid dimers and trimers. In addition, other types of terpenoids, flavonoids, and lignins also exist in the genus Inula. Since 2010, more than 300 new secondary metabolites, including several known natural products that were isolated for the first time from the genus Inula. Most of them exhibited potential bioactivities in various diseases. The review aimed to summarize the advance of recent researches (2010–2020) on phytochemical constituents, biosynthesis, and pharmacological properties of the genus Inula for providing a scientific basis and supporting its application and exploitation for new drug development.

Thymus broussonetii Boiss (T. broussonetii) is a rare medicinal and aromatic plant. It is widely used in traditional medicine to treat several diseases, including diarrhea, fever, cough, irritation, skin diseases, rheumatism, respiratory ailments, influenza, and digestion problems. In this review, we have critically summarized previous data on T. broussonetii about its phytochemistry, botanical and geographical distribution, toxicological investigation, and pharmacological properties. Using scientific research databases such as Wiley Online, SciFinder, ScienceDirect, PubMed, SpringerLink, Web of Science, Scopus Wiley Online, and Google Scholar, the data on T. broussonetii were collected and discussed. The presented data regrouped bioactive compounds and biological activities of T. broussonetii. The findings of this work showed that essential oils and extracts of T. broussonetii exhibited numerous pharmacological activities (in vitro and in vivo), particularly antibacterial, antifungal, antioxidant, anticancer, anti-inflammatory, insecticidal, antipyretic, antinociceptive, and immunological and behavioral effects. While toxicological studies of T. broussonetii essential oils and extracts are lacking, modern scientific tools revealed the presence of different classes of secondary metabolites such as terpenoids, alkaloids, flavonoids, tannins, coumarins, quinones, carotenoids, and steroids. T. broussonetii essential oils, especially from the aerial parts, exhibited potent antibacterial, antifungal, and antioxidant effects. An in-depth toxicological investigation is needed to validate the efficacy and safety of T. broussonetii extracts and essential oils and their secondary metabolites. However, further pharmacokinetic and pharmacodynamic studies should be performed to validate its bioavailability.

The genus Trichocolea (Fam. Trichocoleaceae) comprise 31 species of liverworts, most of which are endemic in a wide geographical area of the southern Pacific Ocean including New Zealand, Tasmania, and South Australia. Although few reports have been reported on the phytochemistry and pharmacognosy of these briophytes, data reported so far show a great pharmacological potential for their secondary metabolites. Phytochemicals isolated from Trichocolea spp. include benzoate esters, flavonoids, and diterpenes. The reported biological activities of these natural compounds refer to cancer cells growth inhibitory, antibacterial, anti-fungal, and anti-oxidant effects. The aim of this short review is to examine in detail from a phytochemical and pharmacological point of view what is reported in the current literature about the properties of phytopreparations or individual chemicals obtained from liverworts belonging to the Trichocolea genus.

Cayratia trifolia Linn. Domin Syn. Vitis trifolia (Family: Vitaceae) is commonly known as Fox grape in English; Amlabel, Ramchana in Hindi and Amlavetash in Sanskrit. It is native to Asia and Australia. This plant is used for chronic fever, rheumatic, anti-inflammatory etc. In the present study, quantitative analysis and free radical scavenging activities of stem ethanolic extract of Cayratia trifolia was investigated. The extract was found to possess more secondary metabolites and it exhibit radical scavenging activities, Based on the results it can be concluded that, the stem ethanolic extract of Cayratia trifolia which contains high amount of secondary metabolites and exhibits free radical scavenging activities, phytochemistry from leaves and stems using spectral techniques. This research paper provides information mainly on various biological activities like antimitotic, antidiabetic and anti-implantation and several medicinal uses. Biological activities of few of them have been studied maximum concentration of Proteins (58.4mg/gdw) and minimum concentration in total soluble sugar (0.7mg/gdw) and maximum concentration of Lipid peroxidase (5.01mg/gdw) and minimum concentration in FRAP (0.197mg/gdw). Keywords: Cayratia trifolia; Vitaceae; Phytochemistry; Antioxidant.

This review covers the phytochemical, biological properties, and synthesis of naturally occurring homoisoflavonoids. Homoisoflavonoids are a very important class of secondary metabolites whose numbers have grown from 20 in 1981 to 157 at the present time. They are found to occur in seven plant families. For the purpose of this review they are classified into five groups: 3-benzylchroman-4-ones, 3-benzylflavans, Δ3,9 and Δ2,3 3-benzylchroman-4-ones, benzocyclobutenes (scillascillins) and rearranged homoisoflavonoids (brazilin and related compounds). Biosynthetically, the 3-benzylchroman-4-ones and the 3-hydroxy-derivatives have been shown to arise from a chalcone precursor (sappanchalcone) and there is strong evidence that this isolable intermediate can be converted into the diverse structures such as the benzocyclobutenes (scillascillins) and the rearranged, brazilin-type compounds. Homoisoflavonoids possess a wide range of biological activities, including, antimicrobial, antimutagenic, anti-inflammatory, antidiabetic, etc, properties. The review also surveys the chemical synthesis of natural homoisoflavonoids. Analytical methods for the determination of these important metabolites are also reviewed. The last section is devoted to a brief review of the diagnostic NMR spectroscopic features of homoisoflavonoids. A comprehensive Table has also been compiled listing all known metabolites, their sources, melting points and optical rotation values (where available) and references.

Mikania é o maior gênero da tribo Eupatorieae, com cerca de 430 espécies, sendo amplamente distribuído no Brasil, com aproximadamente 200 espécies descritas. Dentro deste gênero, Mikania cordifolia, M. micrantha e M. glomerata são comumente chamadas de guaco e estão entre as espécies mais usadas popularmente, principalmente para o tratamento de febre, reumatismo, doenças do trato respiratório e contra picadas de cobra. No presente trabalho, foram realizados estudos fitoquímicos destas três espécies e foram analisados os efeitos dos tipos de adubação, da radiação solar e do estresse hídrico sobre a produção de metabólitos secundários. Primeiramente, através de estudos fitoquímicos, foram identificados 62 compostos. As frações polares das espécies apresentaram como compostos majoritários derivados fenilpropanóicos, destacando-se o Ácido 3,5-dicafeoilquínico em M. glomerata e M. micrantha e o Ácido Fertárico em M. cordifolia. Na espécie M. glomerata também foram identificados derivados do Ácido glucárico di e tri esterificados por ácidos caféicos, até o momento não descritos na literatura, além de flavonóides sulfatados, os quais também estão presentes em M. micrantha. Nas frações apolares foi verificada a presença de triterpenos, principalmente em M. cordifolia e derivados do Ácido Caurenóico em M. glomerata e M. micrantha. As lactonas sesquiterpênicas foram encontradas em M. cordifolia (esqueleto melampolido) e em M. micrantha (esqueleto micranolido). A análise dos cultivares de M. glomerata e M. cordifolia, revelou uma grande influência das condições de cultivo na composição dos metabólitos secundários. Os experimentos mostraram uma grande variação entre a concentração dos compostos presentes nas duas espécies de Mikania, sendo verificado que as condições de cultivo e principalmente as taxas de luminosidade são de extrema importância na acumulação desses metabólitos. O estresse hídrico não apontou efeitos significativos no acúmulo de substâncias em M. glomerata. As análises histoquímicas se mostraram eficazes na obtenção de informações a respeito da localização de compostos fenólicos nas folhas de M. glomerata.
Mikania is the largest gender of the tribe Eupatorieae, with about 430 species, being distributed thoroughly in Brazil, with approximately 200 described species. In this gender, Mikania cordifolia, M. micrantha and M. glomerata are commonly called \"guaco\" and are among the more popularly used species, mainly for the treatment of fever, rheumatism, diseases of the breathing tract and against snake bites. In the present work, phytochemical studies of these three species were carried out and the effects of the fertilization types, the solar radiation and the hydric stress upon the production of secondary metabolites were analyzed. Firstly, through phytochemical studies, 62 compounds were identified. The polar fractions of the species presented as majority compounds phenylpropanoic derivatives: 3,5-Dicaffeoylquinic acid in M. glomerata and M. micrantha and Fertaric acid in M. cordifolia. In M. glomerata were also identified glucaric acid derivatives di- and tri-esterified with cafeic acids, which are no described in the literature until the moment, besides sulfated flavonoids, which are also present in M. micrantha. In the apolar fractions the triterpenes presence were verified mainly in M. cordifolia and kaurenoic acid derivatives in M. glomerata and M. micrantha. The sesquiterpene lactones were found in M. cordifolia (melampolide skeleton) and in M. micrantha (micranolide skeleton). The analysis of M. glomerata and M. cordifolia cultivars revealed a great influence of the cultivation conditions in the secondary metabolites composition. The experiments showed a great variation among the concentration of the compounds in the two species of Mikania, being verified that the cultivation conditions and mainly the taxes of solar radiation are of extreme importance in the accumulation of these metabolites. The hydric stress didnt have significant effects in the accumulation of substances in M. glomerata. The histochemical analyses were effective in supply information regarding location of phenolic compounds in the leaves of M. glomerata.

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Universidade Federal de Sao Carlos
Allelopathy is a process that involves primary or secondary metabolites produced by plants and microorganisms, which influences the growth and development of agricultural and biological systems. The intensity of plant allelopathic effects may depend on the hábitat, age and the biotic and abiotic conditions during the seasons in which they were collected. When allelopathic substances are purified and identified, they can be used to develop alternative products based on natural compounds to control weed species. The Brazilian savanna (cerrado) has very stressful environment conditions, mainly in dry periods, and should favor a greater variety of allelochemicals in Rapanea ferruginea (Ruiz & Pav.) Mez and Rapanea umbellata (Mart.) Mez (Primulaceae), which have leaves with resin canals and minute secretory glands, sparse throughout the abaxial surface, that can accumulate terpenes or tannins. This thesis hypothesis is that there must be allelopathic substances in the species of Rapanea to favor their establishment in the savanna and that they should be influenced by seasonal factors or by plant age. Allelopathy occurs by the release of allelochemicals in the environment and these may have economic importance, serving as molecular models for the production of natural herbicides, less harmful to the environment. In the first chapter, we compared the effect of plant age and season of leave collection on the allelopathic activity of aqueous extracts of R. ferruginea and R. umbelata. For this, germination and initial length bioassays were conducted using commercially bioindicator cultivated species (lettuce, tomato and onion) under the influence of the aqueous leaf extracts of adults and young individuals from wet and dry season at 10 and 5% (weight of leaf powder per volume of distilled water, g/mL). The extract of adult R. umbellata collected in the dry season showed the highest allelopathic activity and was chosen for the other studies of this thesis. In the second chapter, we compared the allelopathic activity of leaf aqueous extract of R. umbellata (10 and 5%) with the synthetic herbicide Oxyfluorfen on germination and initial length of weed species: barnyardgrass (Echinochloa crus-galli L., Poaceae), wild poinsettia (Euphorbia heterophylla L., Euphorbiaceae) and morning-glory (Ipomoea grandifolia Drammer., Convolvulaceae). In the third chapter, bioprospection, purification and isolation of secondary metabolites of agronomic interest was performed with R. umbellata leaves. Bioassays wheat of etiolated coleoptiles and germination and initial length of cress, lettuce, onion and tomato were performed under the effect of extracts of organic solvents for the direction of the compounds purification. The acetone extract was the most active and therefore was used to be fractionated by chromatographic column. It fractions were purified HPLC and Sephadex column. The isolated and purified compounds were identified by NMR1H and 13C spectra. This thesis results permit we to affirm that allelopathy is one way of the R. ferruginea and R. umbellata species to establish themselves in the savanna. The allelopathic activity of its leaves is influenced to a greater degree by the collection season (most active in dry season) than by plant age. The R. umbellata aqueous leaf extract showed distinct action than the Oxyfluorfen synthetic herbicide, being very active on the root part of the weed species while the synthetic herbicide was more active on the arial parts of these species. The bioprospection of R. umbellata leaves conditioned isolation and purification of the substances lutein and (-)- catechin. (-)-Catechin has the potential to be used as a natural origin and biodegradable herbicide.
Alelopatia é o processo que envolve metabólitos secundários ou primários, produzidos pelas plantas e microrganismos, que influencia o crescimento e o desenvolvimento de sistemas agrícolas e biológicos. A intensidade dos efeitos alelopáticos de uma planta pode depender do hábitat, da idade e condições bióticas e abióticas a que estavam sujeitas na época em que forem coletadas. Quando substâncias alelopáticas são purificadas e identificadas, podem ser utilizadas para o desenvolvimento de produtos alernativos baseados em compostos naturais para o controle de espécies infestantes. O ambiente de cerrado possui condições ambientais bastante estressantes, principalmente na época da seca, e deve favorecer uma maior variedade de aleloquímicos nas espécies Rapanea ferruginea (Ruiz & Pav.) Mez e Rapanea umbellata (Mart.) Mez (Primulaceae), que possuem folhas com canais resiníferos e glândulas secretoras diminutas, esparsas por toda face abaxial, que podem acumular terpenos ou taninos. A hipótese desta tese é que devem existir substâncias alelopáticas em espécies de Rapanea que favoreçam o seu estabelecimento no cerrado e que estas devem ser influenciadas por fatores sazonais ou pela idade das plantas. A alelopatia ocorre pela liberação de aleloquímicos no ambiente e estes podem apresentar importância econômica, servindo de modelos para a produção de herbicidas de origem natural, menos agressivos ao meio ambiente. No primeiro capítulo, comparou-se o efeito da idade e da sazonalidade da época de coleta das folhas sobre a atividade alelopática de extratos aquosos de indivíduos de R. ferruginea e R. umbelata. Para tanto, bioensaios de germinação e comprimento inicial de espécies bioindicadoras cultivadas comercialmente (alface, tomate e cebola) foram realizados sob influência dos extratos foliares aquosos de indivíduos adultos e jovens provenientes de estação chuvosa e seca à 10 e 5% (massa de pó de folhas por volume de água destilada, g/mL). O extrato de R. umbellata adulta coletada em estação seca apresentou atividade alelopática elevada e foi escolhido para os demais estudos desta tese. No segundo capítulo, comparou-se a atividade alelopática do extrato aquoso foliar de R. umbellata (10 e 5%) com a de um herbicida sintético (oxifluorfem) sobre a germinação e comprimento inicial de espécies infestantes de culturas agrícolas: capim-arroz (Echinochloa crus-galli L., Poaceae), amendoim-bravo (Euphorbia heterophylla L., Euphorbiaceae) e corda-de-viola (Ipomoea grandifolia Drammer., Convolvulaceae). No terceiro capítulo, a bioprospecção, purificação e isolamento de metabólitos secundários de interesse agronômico foi realizada com folhas de R. umbellata. Para que houvesse um direcionamento na purificação destes compostos, bioensaios de coleóptilos estiolados de trigo, germinação e comprimento inicial de agrião, alface, cebola e tomate foram realizados sob efeito de extratos de solventes orgânicos. O extrato acetônico foi o mais ativo e, portanto, foi utilizado em fracionamento em coluna cromatográfica. Suas frações foram purificadas em CLAE e coluna de Sephadex. Os compostos isolados e purificados foram identificados através de RMN1H e 13C. Os resultados obtidos com esta tese permitem dizer que a alelopatia é uma das formas das espécies de R. ferruginea e R. umbellata se estabelecerem no cerrado. A atividade alelopática de suas folhas é influenciada em maior grau pela época de coleta (mais ativas em estação seca) do que pela idade das plantas. O extrato foliar aquoso de R. umbellata apresentou ação distinta do herbicida sintético oxifluorfem, sendo bastante ativo sobre a parte radicular das espécies infestantes, enquanto o herbicida sintético foi mais ativo sobre a parte aérea destas espécies. A bioprospecção das folhas de R. umbellata levou ao isolamento e a purificação das substâncias luteína e (-)-Catequina. A (-)-Catequina apresenta potencial para ser utilizada como herbicida de origem natural e biodegradável.

Foram isoladas de Piper scutifolium e P. corcovadensis seis amidas, incluindo a piperovatina, piperlonguminina, isopiperlonguminina e corcovadina, duas inéditas (scutifoliamida A e scutifoliamida B), além de duas aristolactamas (piperolactama C e stigmalactama). A partir de P. tuberculatum foram isoladas as amidas piplartina e pelitorina e os ésteres (E)-3,4,5-trimetoxicinamato de etila (11) e 3,4,5- trimetoxidiidrocinamato de etila (12), esse último obtido pela primeira vez de origem natural. Em função da atividade biológica apresentada pelas amidas isoladas, foram sintetizadas 5-fenil-pentadienamidas e 3-cinamamidas com diferentes substituintes nos anéis aromáticos e na porção amídica. Os extratos, produtos naturais isolados e sintéticos foram submetidos a ensaios de atividade antifúngica frente Cladosporium cladosporioides e C. sphaerospermum, antimicrobiana frente à Candida albicans, C. krusei, C. parapsilosis e Cryptococcus neoformans, inibidora de acetilcolinesterase, carrapaticida frente à Boophilus microplus e citotóxica frente a linhagens tumorais humanas. Para a atividade antifúngica contra C. cladosporioides e C. sphaerospermum foi constatada maior atividade para as N-isobutil e N-pentilamidas sem substituintes no anel aromático. As N-isobutilamidas foram mais ativas como inibidores de acetilcolinesterase; contra B. microplus grande atividade foi apresentada por piperovatina, e os ensaios de citotoxicidade indicaram que o grupo 5,6-dihidropiridin- 2(1H)-ona é fundamental para a atividade. As plântulas de P. corcovadensis apresentaram em sua composição predominantemente piperovatina e assim foram utilizadas para estudos com incorporação de acetato de sódio-[1-14C] e L-fenilalanina - [U-14C] na mesma. As plântulas e calos obtidos para P. scutifolium não apresentaram produção significativa de metabólitos secundários. O estudo do metabolismo fenilpropanoídico de P. regnellii resultou no isolamento parcial da enzima responsável pela conversão de conocarpano em eupomatenóide-6.
Six amides were isolated from Piper scutifolium and P. corcovadensis including piperovatine, piperlonguminine, isopiperlonguminine and corcovadine, the new scutifoliamide A and scutifoliamide B and also two aristolactams (piperolactam C and stigmalactam). From P. tuberculatum the amides piplartine and pellitorine and two esters, ethyl (E)-3,4,5-trimethoxycinnamate (11) and ethyl 3,4,5- trimethoxydihydrocinnamate (12) were isolated, this last one obtained for the first time from natural sources. Due to the biological activity observed for the natural amides, 5- phenyl-pentadienamides and 3-cinnamamides having different substituents in the aromatic ring and amide moietis were synthesized. Extracts, isolated and synthetic compounds were assayed against Cladosporium cladosporioides, C. sphaerospermum, Candida albicans, C. krusei, C. parapsilosis and Cryptococcus neoformans, inhibitory of acetylcholinesterase, against the tick Boophilus microplus and citotoxic against human cell lines. A higher activity was observed against C. cladosporioides and C. sphaerospermum for N-isobutylamides and N-pentylamides having no substituents in the aromatic ring. N-isobutylamides were very active inhibitors of acetylcholinesterase; piperovatin was the most active against B. microplus and 5,6-dihydropyridin-2(1H)-one moiety was essential as the citotoxicity is concerned. Plantlets of P. corcovadensis contained piperovatine as major compound and thus were used as model for incorporation of sodium acetate-[1-14C] and L-phenylalanine-[U-14C]. The production of secondary metabolites in plantlets and callus of P. scutifolium was not significant. The studies of phenylpropanoid metabolism in P. regnellii was addressed to partial purification and characterization of the enzyme involved in the conversion of conocarpan to eupomatenoid-6.

Le projet Plantinauv dans lequel s’inscrivent les travaux de ce mémoire de thèse, a pour but la valorisation du patrimoine botanique d’Auvergne en identifiant des plantes d’intérêts alimentaires et médicinales possédant des activités anti-inflammatoires, et de permettre leur commercialisation (ou celle de leurs bioactifs isolés) sous la forme de produits nutraceutiques, cosmétiques et/ou vétérinaires. Ce projet implique un consortium de partenaires académiques (UMR UNH) et industriels du pôle de compétitivité Vegepolys Valley (Greentech, Domes Pharma, AltoPhyto). Parmi les plantes de la flore auvergnate, seize ont été sélectionnées pour évaluer le potentiel anti-inflammatoire de leurs extraits (tests physico-chimiques et biologiques). Six d’entre elles, présentent sur différentes listes règlementaires (nutraceutique, cosmétique, vétérinaire), ont fait l’objet d’études phytochimiques. Le fractionnement chimio-et bio-guidé de L. sylvatica et D. fullonuma permis d’isoler de nouveaux métabolites secondaires d’intérêt. Quatre nouveaux phénanthrènes présentant des propriétés antiprolifératives prometteuses ont été isolés des parties aériennes de L. sylvatica. La mise en évidence des principaux marqueurs et le dosage de certains d’entre eux ont été réalisés pour les quatre autres plantes (P. erecta, T. angustifolia, H. Stoechas, K arvensis). Enfin, la préparation d’extraits industrialisable à partir de ces plantes a été mise au point dans le but de développer de nouveaux ingrédients commercialisables
The research work of this thesis, included in the Plantinauv project,aims to enhance the botanical heritage of Auvergne by identifying plants of medicinal and nutritional interest exhibiting anti-inflammatory activities, and to allow their merchandising (or that of their isolated bioactive agents) in the form of nutraceutical, cosmetic and / or veterinary products. This project involves a consortium of academic(UMR, UNH) and industrial partners from the cluster Vegepolys Valley (Greentech, Domes Pharma and Altophyto).Among the plants of the Auvergne flora, sixteen were selected to assess the anti-inflammatory potential of their extracts (chemical and biological tests). Six of them, present on different regulatory lists (nutraceutical, cosmetic, veterinary), have been the subject of phytochemical studies.The chemo-and bio-guided fractionation of L. sylvaticaand D. fullonumextracts allowed the isolation of new secondary metabolites. Four new phenanthrenes with promising anti-proliferative activities on cancer cells were isolated from L. sylvatica. The phytochemical profiles of the four other plants (P. erecta, T. angustifolia, H. stoechas, K arvensis) were also determined. Finally, the standardization of the different plant extracts was studied in order to develop new marketable ingredients

This work is an account of the phytochemical analysis of two genera, Vernonia and Vepris which are used as remedies for illness by the Kalenjin community of Kenya. Species of Vernonia are known to yield sesquiterpene lactones, which typify the genus whereas Vepris is rich in alkaloids and limonoids which have a wide range of biological activities. The species studied in this work were Vernonia auriculifera, Vernonia urticifolia, Vepris glomerata and Vepris uguenensis. Phytochemical studies revealed a range of compounds being present in the four species. From Vernonia, triterpenoids, a sesquiterpene amine, a carotenoid and a polyene were isolated. This was the first account of a sesquiterpene amine from a plant species and the first account of the novel polyene. The triterpenoids showed moderate antibacterial activity, with b-amyrin acetate and oleanolic acid being effective at decreasing adhesion of selected gram-negative and gram-positive bacteria. Lutein and urticifolene showed good antibacterial activity against Enterococcus feacium and Pseudomonas aeruginosa. In Vepris, a range of compounds were isolated, belonging to the furoquinoline alkaloids, coumarins, flavonoids, cinnamic acid derivatives, lignins, cinnamaldehydes, triterpenoids and limonoids. Five new compounds; a cinnamaldehyde derivative (glomeral), two flavonoids (veprisinol, uguenenprenol) and two A, D-seco-limonoids (uguenensene and uguenensone) were amongst the compounds isolated. Antibacterial studies showed that glomeral inhibited the growth of Staphylococcus aureus and Shigella dysentrieae at low concentrations (MIC of 2 μg mLˉ¹ and 0.4 μg mLˉ¹ respectively). Antioxidant assays of several compounds revealed that, veprisinol, isohaplopine-3,3’-dimethylallyl ether, uguenenprenol and 7-O-methylaromadenrin are good antioxidant agents. The limonoids isolated from Vepris uguenensis also make up an interesting biogenetic relationship. Structural elucidation was carried out by 1D and 2D NMR spectroscopy in conjuction with mass spectrometry, infrared, ultraviolet and circular dichroism analysis where applicable. Biological assays were carried out using standard methods at laboratories in the University of KwaZulu-Natal and Kenya Medical Research Institute (KEMRI-Nairobi).
Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2012.