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BACKGROUND Chia (Salvia hispanica L.) is a functional food from Central America. Interest in it is growing rapidly due to the many health benefits from the seed. However, when chia is grown at high latitudes, seed yield may be low whereas a high stem biomass and immature inflorescences are produced. Little is known about the chemical composition and the properties of stems and flowers. In this work, the metabolite profile, the antioxidant activity, and the total polyphenol content of stems and inflorescences were evaluated in a factorial experiment with different chia populations (commercial black chia and long‐day flowering mutants G3, G8, and G17) and irrigation (100% and 50% of evapotranspiration). RESULTS The results show the influence of irrigation and seed source on the antioxidant activity and total polyphenol content of chia flower and stem. Inflorescences exhibit higher antioxidant activity, suggesting their potential use as natural antioxidant. The mutants G3 and G8, at 50% irrigation, contained the highest amounts of compounds with nutraceutical value, especially within the flower. The mutant G17 showed lower antioxidant activity and polyphenol content compared to other seed sources but exhibited high omega 3 content in flowers but low in stems. This indicates that chia varieties should be chosen according to the objective of cultivation. CONCLUSION These findings, indicating a close relation of metabolite content with irrigation and seed source, may provide the basis for the use of chia flower and stem for their nutraceutical value in the food, feed, and supplement industries. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Euphorbia myrsinites is one of the oldest spurges described and used in folk medicine. It is characterized by blue-grey stems similar to myrtle, and it is spread in the Mediterranean region, Asia, and the USA. Chemical analysis of E. myrsinites collected in Turkey afforded the isolation of 4 diterpenes based on the so-called myrsinane skeleton being tetraesters of the tetracyclic diterpene alcohol myrsinol. In this study, the phytochemical analysis of this species collected in Italy has been undertaken to afford the isolation of a new atisane diterpene, named myrsatisane, 3 ingenol derivatives, along with the 4 tetraester derivatives previously found. A triterpene compound based on the euphane skeleton has also been isolated. Structural elucidation of the new myrsatisane was based on spectroscopic techniques, including HR-MS and 1- and 2-dimensional NMR experiments. Its relative configuration was determined by NOE correlations, while absolute stereochemistry was obtained by quantum-mechanical DFT studies. While diterpenes with the atisane skeleton are relatively common in Euphorbia species, this is the first report of an atisane diterpene from E. myrsinites. All the isolated terpenes were tested for anti-inflammatory activity on J774A.1 macrophages stimulated with lipopolysaccharide by evaluation of nitrite and pro-inflammatory cytokine Il-1β levels. Among tested compounds, the 3 ingenol diterpenes exhibited a dose-dependent (0.001 – 3 µM) significant activity, thus showing their potential as anti-inflammatory drug candidates.

Abiotic and biotic stresses affect plant physiology and growth. The development of metabolomics, along with other -omics technologies, allowed in depth analysis of the reactive processes characterizing plant stress as the result of the alteration of metabolites and gene expressions. Here, we organize and interpret data from 151 studies to provide an overview about metabolomic shift after exposure to either abiotic or biotic stresses including drought, salinity, heat, heavy metal, cold, pathogens and insects. Data showed that amino acids, organic acids, sugars, and sugar alcohols quantities are influenced by stresses. Proline for example, increased in almost every stress condition, while other molecules increased or decreased depending specifically on plant tissue, plant species and type of applied stress. We concluded that although it is difficult to predict precisely what a stress will cause, some general metabolic trends can be described and improve our understanding of plant response to biotic and abiotic stresses.

The incidence of post-menopausal osteoporosis is increasing globally. In post-menopausal osteoporosis, there is deficiency in oestrogen level resulting in bone loss and fractures. Bone formation is under the control of different hormones. In the present review, we highlight few pathways such as RANKL/RANK, apoptosis and Wnt/β-catenin signalling pathways and phytoestrogens involved in the bone metabolism. RANKL/RANK signalling is responsible for regulating the formation and activation of multinucleated osteoclasts from their precursors which is responsible for the survival of normal bone remodelling. Apoptosis regulates the development, growth and maintains the bone tissues. The Wnt pathway is an important pharmacological target for bone anabolic drugs and its future discovery. In today’s world, herbal remedies are used to treat post-menopausal osteoporosis as these products contain phytoestrogens. These phytoestrogens are oestrogen like compounds which influence bone metabolism. The phytoestrogens provide better therapeutic effect in reducing the RANKL, osteoclastogenesis, inflammatory markers, and increase the osteogenic markers in the bone cells or osteoblasts. We discuss the mechanism of action of few phytoestrogens such as genistein, daidzein and equol which are beneficial for improvement of the bone health. Daidzein enhances osteoblast growth via the upregulation of BMP expression in primary osteoblast cells and it is a potential antiosteoporotic agent. Genistein also possesses antioestrogenic property by virtue of its competitive binding to the same receptors as oestradiol. Equol regulates the bone loss via hemopoiesis and inflammatory cytokine production. Thus, phytoestrogens could be efficiently used as osteoprotective agents for the treatment of individuals with post-menopausal osteoporosis.

Introduction Most secondary metabolites from plants have a prominent defensive role and repellency against predators and microbial pathogens. These properties largely vary among plant species and offer potential applications as biologically active compounds in medicine as well in agriculture. Objectives We propose a new procedure that combine different spectroscopic techniques and multivariate data analysis to determine the chemical composition and the relative amounts of each metabolites and/or each class of organic compounds. The approach was used for a rapid identification of secondary metabolites from leaf and root of eight Mediterranean plants species. Methodology The polar and the apolar extracts of two leaves and roots of each plant were analysed by proton nuclear magnetic resonance (1 H-NMR) and gas chromatography coupled to mass spectrometry (GC-MS), respectively. Multivariate data analysis was used for a faster interpretation of data. Results The metabolic fingerprint of the Mediterranean plants, Acanthus mollis, Dittrichia viscosa, Festuca drymeja, Fraxinus ornus, Fagus sylvatica, Hedera helix, Quercus ilex, and Typha latifolia, showed a complex chemical composition, being specific for each species and plant tissue. Two alditols, mannitol and quercitol, were found in manna ash (Fraxinus ornus) and holm oak (Q. ilex) polar leaf extracts, respectively. The highest levels of aromatic compounds were found in D. viscosa and T. latifolia. Fatty acids were the predominant class of compounds in all apolar extracts under investigation. Triterpene were almost exclusively found in roots, except for holm oak, where they constitute 58% of total extract. Steroids were widespread in leaf extracts. Conclusion The major advantages of the proposed approach are versatility and rapidity, thus making it suitable for a fast comparison among species and plant tissue types.

Papaver rhoeas L. (Papaveraceae), commonly known as corn poppy, is a cosmopolitan weed and edible plant capable of possessing biological properties, thus positive correlating with human health. The plant is also known as field poppy, flanders poppy or shirley poppy. It can be consumed raw or cooked, and has been traditionally used to treat nervousness, insomnia, digestive and respiratory disorders, baldness, eye infections, as well as measles treatment. This paper is aimed to contribute to the knowledge of corn poppy by providing a critical review of the botanic characteristics, the traditional uses, the plant chemistry and pharmacology.

The Red Palm Weevil (RPW), Rhynchophorus ferrugineus (Coleoptera: Curculionidae), is an insect pest native to Southeast Asia, which has become the major threat to palms in the Mediterranean Basin, mainly due to the movement of infested planting material. In case of infestation, the exotic weevil is difficult to control effectively and host plants often die. Chamaerops humilis (Arecales: Arecaceae) palms are reported as resistant to RPW, but little is known about the chemical basis of this resistance and about the identity of the endogenous metabolites that may be involved. In the present study, we focused on the potential toxic effect of catechin against RPW larvae. In laboratory bioassays, purified catechin from C. humilis leaves was provided to two-and five-week old RPW larvae at three different concentrations. We found that catechin can impair the survival of RPW, causing toxicity at concentrations as low as 0.03 mg g-1. Larval mortality was concentra-tion-dependent, and furthermore larval age influenced the effect of catechin, older larvae being more susceptible than younger ones. The observed toxicity of catechin on RPW larvae agrees with the hypothesis that this compound contributes to C. humilis being an unsuitable host for this insect pest.

Background . A novel coronavirus, the SARS-CoV2, was revealed to be the cause of COVID19, the pandemic disease that already provoked more than 555.324 deaths in the world (July 10, 2020). No vaccine treatment has been defined against SARS-CoV2 or other human coronaviruses (HCoVs), including those causing epidemic infections, neither appropriate strategies for prevention and care are yet officially suggested. Scope and approach . We reviewed scientific literature on natural compounds that were defined as potentially effective against human coronaviruses. Our desk research identified non-chemically modified natural compounds that were shown (in vitro) and/or predicted (in silico) to act against one or more phases of human coronaviruses cell cycle. We selected all available information, merged and annotated the data to define a comprehensive list of natural compounds, describing their chemical classification, the source, the action, the specific target in the viral infection. Our aim was to collect possible compounds for prevention and care against human coronaviruses. Key findings and conclusions . The definition of appropriate interventions against viral diseases need a comprehensive view on the infection dynamics and on necessary treatments. Viral targeting compounds to be exploited in food sciences could be of relevant interest to this aim. We collected 174 natural compounds showing effects against human infecting coronaviruses, providing a curated annotation on actions and targets. The data are available in anti-HCoV, a web accessible resource to be exploited for testing and in vivo trials. The website is here launched to favour a community based cooperative effort to call for contribution and expand the collection. To be ready to fight., Highlights • The new SARS-CoV2 caused more than 555.000 deaths in seven months. • HCoVs similarities suggest possible similar action against them. • No official treatment for prevention and care against HCoVs is yet approved. • In silico and experimental analyses revealed effective compounds against HCoVs. • Comprehensive collections of natural compounds against HCoVs are a resource.

The Contribution of Wild Edible Plants to the Mediterranean Diet: An Ethnobotanical Case Study Along the Coast of Campania (Southern Italy). Wild edible plants, an essential component of people’s diets in the Mediterranean basin, are consumed because they have a positive influence on health, supplying the body with microelements, vitamins, phenols, flavonoids, antioxidants, and fiber. In this paper we provide a list of wild plants used in the local cuisine along the coast of Campania, highlighting the medicinal properties of the most widely used species. Fieldwork was conducted from April 2017 to September 2019; in all, 69 informants were interviewed. We carried out an extensive literature review searching both national and international journals for ethnobotanical articles concerning the whole of Italy and especially the region of Campania, published from 1963 to 2019. The relative frequency of citation (RFC) index for each species is provided. Based on the interviews, 85 species and subspecies distributed in 29 families are documented as being used as food. Asteraceae was the most cited family (26.5%) followed by Brassicaceae and Lamiaceae (7.2%). The culinary uses of 11 wild species (13.5% of the total) were hitherto unreported in the ethnobotanical literature for Campania. The present study confirms the persistence of traditional plant use in the region of Campania. Ethnobotanical data, as well as the phytochemical and nutritional profiles of the species in question, offer insights into designing new dishes such as food pairing with other ingredients to improve nutritional and/or sensory quality (e.g., bitterness reduction, flavor enhancement, antioxidant bioavailability).

Introduction: Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most devastating and harmful pests of tomato (Solanum lycopersicum) crops causing up to 80–100% yield losses. A large arsenal of plant metabolites is induced by the leafminer feeding including defence compounds that could differ among varieties. Objective: To compare the metabolomic changes of different genotypes of tomato (tolerant “T”, susceptible “S” and “F1” hybrid obtained between T and S) after exposition to T. absoluta. Methodology: Nuclear magnetic resonance (NMR) spectroscopy followed by multivariate data analysis were performed to analyse the metabolic profiles of control and infested samples on three different tomato genotypes. Results: Signals related to GABA (γ-aminobutyric acid) were relatively much higher in all infested samples compared to the non-infested plants used as control. Infested T genotype samples were the most abundant in organic acids, including fatty acids and acyl sugars, chlorogenic acid, neo-chlorogenic acid and feruloyl quinic acid, indicating a clear link between the exposure to leafminer. Results also showed an increase of trigonelline in all tomato varieties after exposition to T. absoluta. Conclusion: Metabolomics approach based on NMR spectroscopy followed by multivariate data analysis allowed for a detailed metabolite profile of plant defences, providing fundamental information for breeding programmes in plant crops.

Phytoalimurgy is a term that derives from Greek and Latin by combination of the words φυτόν, which meaning plant, and alimenta urgentia, indicating foods available in case of urgency and necessity. Nowadays, the lack of products from agriculture is fortunately no longer a problem, however, the interest in using the phytoalimurgic plants has increased in the last years due to their rediscovery for use of food ingredients for human health. Among these, common dandelion, Taraxacum officinale, is used since ancient times because of its curative properties. The aim of this review is the contribution to the knowledge of this worldwide-spread phytoalimurgic plant with its botanical, phytochemical and pharmacological description. In vitro and in vivo scientific investigations have confirmed its pharmacological potential by showing antioxidant, antibacterial, anti-inflammatory, antiviral, cytotoxic, diuretic and hepatoprotective properties. Responsible of these activities are bioactive metabolites belonging to different classes, including sesquiterpenoids, caffeoylquinic acids and flavonoids. This allows to include dandelion among the medicinal plants of commercial interest for nutraceutical and phytopharmaceutical industries.

Fire, besides affecting plant litter fate in natural ecosystems, is a widely used tool to manage crop residues in agro-ecosystems. In both cases, burning of plant residues produces highly heterogeneous materials, ranging from little affected plant tissues, to charred substrates, up to mineral ashes, whose chemical nature and biological effects are not yet fully clarified. The aim of our study was to assess the effects of litter treated at different temperatures (100, 200, 300, 400 and 500 °C) on saprotrophic fungi, plant pathogenic microbes, and higher plants. To this purpose, we combined a characterization of 48 organic materials by 13C-CPMAS NMR spectroscopy with a multi-species laboratory bioassay on seven target organisms (one plant and six microbes). Consistent with previous observations, we showed that, as charring temperature increased, litter quality significantly changed, with a progressive loss of O-alkyl C, di-O-alkyl C, and methoxyl and N-alkyl C, coupled with an enrichment in aromatic C, irrespective of plant litter types. Noteworthy, the bioassay showed that untreated litter had a major inhibitory effect on the test plant, while it acted as a suitable substrate sustaining microbial growth. On the contrary, as litter was charred its biochemical quality decreased with increasing temperature because of a progressive disappearance of easily degradable C sources and enrichment of recalcitrant aromatic fractions. Therefore, charred litter became an organic material suitable to sustain plant growth, but was largely inhibitory for microbial saprotrophic growth. This work demonstrates that defining litter quality by 13C-CPMAS NMR improves our understanding of the substrate preferences of both plant and microbes for different litter types as well as for charred organic materials.

Plants belonging to the genera Allium and Aster are widely distributed in nature and have been used as food and/or medicine. Their wide use was mainly due to the medicinal properties attributed to these plants since ancient times, recently supported by epidemiological and laboratory studies. Saponin compounds, responsible for many pharmacological activities, are quite abundant in these plants. Thus, a deep knowledge about the saponin composition of these vegetables appears to be essential and could promote the discovery of new potential leads. As part of our continuing research aimed at the identification of bioactive metabolites, we have addressed our attention to several Allium and Aster species. The study resulted in the isolation of over fifty saponins of furostane, spirostane, cholestane, and oleane-type structures. Some of the isolated compounds exhibited promising antiproliferative, antifungal, and antispasmodic activities. Their structure, distribution and bioactivity will be reported here together with a brief overview of the literature on Allium and Aster saponins.

The phenol compositions of two cultivars of carnation (Dianthus caryophyllus) namely “Gloriana” and “Roland”, which are partially and highly resistant, respectively, to Fusarium oxysporum f. sp. dianthi have been investigated with the aim of determining if endogenous phenols could have an anti-fungal effect against the pathogen. Analyses were performed on healthy and F. oxysporum-inoculated in vitro tissues, and on in vivo plants. Two benzoic acid derivatives, protocatechuic acid (3,4-dihydroxybenzoic acid) and vanillic acid (4-hydroxy-3-methoxybenzoic acid), were found within healthy and inoculated tissues of both cultivars, together with the flavonol glycoside peltatoside (3-[6-O-(α-L-arabinopyranosyl)-β-D-glucopyranosyl] quercetin). These molecules proved to be only slightly inhibitory towards the pathogen. 2,6-Dimethoxybenzoic acid was detected in small amounts only in the inoculated cultivar “Gloriana”, while the highly resistant cultivar “Roland” showed the presence of the flavone datiscetin (3,5,7,2′-tetrahydroxyflavone). The latter compound exhibited an appreciable fungitoxic activity towards F. oxysporum f. sp. dianthi. Copyright © 2003 John Wiley & Sons, Ltd.

Three new furostanol saponins named capsicoside E (1), capsicoside F (2), and capsicoside G (5) were obtained from the seeds of Capsicum annuum L. var. acuminatum along with known oligoglycosides (3, 4, and 6-10). On the basis of chemical and spectroscopic analyses, the structures of these new furostanol oligoglycosides were elucidated as 26-O-beta-D-glucopyranosyl-22-O-methyl-5alpha-furost-25(27)-en-2alpha,3beta,22xi,26-tetraol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (1), 26-O-beta-D-glucopyranosyl-(25R)-5alpha-furost-20(22)-en-2alpha,3beta,26-triol-3-O-beta-D-glucopyranosyl (1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (2), and 26-O-beta-D-gluco-pyranosyl-(25R)-5alpha-furosta-3beta,22xi,26-triol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (5). The isolated saponins showed higher antimicrobial activity against yeasts than against common fungi. Data indicated that the antiyeast activity was related to the combination of the oligosaccharide chain (S1, S2, or S3) with an O-methyl group at R(3) and the presence of a hydroxyl group at the C-2 position.

An investigation of the extracts from Allium neapolitanum has led to the isolation of 13 flavonoid glycosides, based on kaempferol, quercetin and isorhamnetin. Four of them are new compounds and have been identified as: kaempferol 3-O-{[2-O-α- l -rhamnopyranosyl -4-O-β- d -glucopyranosyl]-β- d -glucopyranoside} , isorhamnetin 3-O-{[2-O-α- l -rhamnopyranosyl -6-O-β- d -glucopyranosyl]-β- d -glucopyranoside } , isorhamnetin 3-O-{[2-O-α- l -rhamnopyranosyl -6-O-β- d -glucopyranosyl]-β- d -glucopyranoside }-7-O-β- d -glucopyranoside and isorhamnetin 3-O-{[2-O-α- l -rhamnopyranosyl -6-O-β- d -gentiobiosyl]-β- d -glucopyranoside } . The isolated compounds were evaluated for their anti-aggregation human platelet activity.

New pentacyclic sesterterpenes, lintenolide A ( 2 a, b ) and lintenolide B ( 3 a, b ), have been characterized from the caribbean sponge Cacospongia cf. linteiformis . The structure elucidation of these compounds was accomplished by using 2D NMR experiments, including 1 H- 1 H (COSY), 1 H- 13 C (HETCORR and COLOC) and rotating frame NOE (ROESY). Compounds showed high ichthyotoxicity and antifeedant activity, which suggest their potential role as natural feeding deterrents.

Two novel glycolipids with a very rareα(1 → 4) diglucosyl structure have been isolated from the thermophilic bacterium Thermotoga maritima. The structures of these compounds, on the basis of chemical procedures and spectroscopic studies (FAB-MS and NMR), were shown to be: 1(3),2- dipalmitoyl -3(1)-[ glucopyranosyl -(6- decanoyl )-α- d -(1→ 4)- glucopyranosyl -α- d ]- glycerol (Glycolipid 1) and 1(3), 2-dipalmitoyl-3(1)-[glucopyranosyl-α- d -(1 → 4)-glucopyranosyl-α- d ]-glycerol (Glycolipid 2).

The chapter discusses the interactions of relatively low molecular weight and largely lipophilic secondary plant metabolites with insects and some other invertebrates. This includes compounds stored within plant tissues that are toxic to insects by a range of mechanisms. It covers metabolites that are both constitutively produced and those that are induced in response to defence signalling stimuli including insect attack. Also included are volatile compounds released from plants that act as signals (semiochemicals) detected by herbivorous insects and those that interact with insects at higher trophic levels. Finally, plant to plant communication is described.

Triterpenoid saponins are secondary metabolites showing a remarkable structural variety, as well as notable biological activities. They are synthesised via the isoprenoid pathway by 2,3-oxidosqualene cyclization mediated by oxidosqualene cyclase (OSC) enzymes. In our previous work, three new oleanane-type triterpene saponins (astersedifolioside A–C) were isolated from the aerial tissues of Aster sedifolius L. In this work, the full-length cDNA of a new OSC, designated AsOXA1 , was isolated from A. sedifolius . The AsOXA1 open reading frame consisting of 2286 bp was predicted to encode a protein of 761 amino acid residues. The deduced amino acid sequence of AsOXA1 showed QW and DCTAE motifs which are highly conserved among the known triterpene synthases. In addition, the comparative and phylogenetic analysis evidenced that AsOXA1 was closely related to other plant OSCs, and particularly, β-amyrin synthases including that one of Panax ginseng with which it shared a high degree of identity (79%). Recombinant AsOXA1 has been shown to produce β-amyrin in yeast. RT-PCR analysis evidenced that AsOXA1 was a tissue-specific gene differentially expressed during plant development. Transcripts of AsOXA1 accumulated strongly in leaf at the early reproductive stage but were deficient in root. On the contrary, the accumulation of astersedifoliosides resulted 10-fold higher in roots than in aerial tissues. Molecular and biochemical results have been discussed.

Armillaria mellea, the causal agent of root rot, is a fungal pathogen which proved able to convert the leguminous plant antifungal compound 4′,5,7-trihydroxyisoflavone (genistein) into intermediate metabolites. After suitable periods of incubation, the metabolites were extracted and concentrated from liquid culture media, containing both the isoflavone and the fungus. After purification by column chromatography, the molecular structure of the metabolites was determined by means of mass spectrometry and nuclear magnetic resonance analyses. Five different compounds were identified: 1,3,5-trihydroxybenzene, 4-hydroxyphenylacetic acid, 2,5-dihydroxyphenylacetic acid (homogentisic acid), its lactone 5-hydroxy-2(3H)-benzofuranone, and 1,4-benzoquinone. In vitro experiments showed that while the starting compound, i.e. genistein, has some activity in inhibiting the growth of the fungal pathogen, the degradation products are devoid of any appreciable fungitoxic activity. Moreover, results show that the i...

Twelve new diterpenes, named amygdaloidins A–L ( 1–12 ), possessing a unique substitution pattern of the jatrophane skeleton, have been isolated from the wood spurge, Euphorbia amygdaloides L. (Euphorbiaceae). The chemical structures of amygdaloidins A–L have been established through a combination of extensive nuclear magnetic resonance and mass spectrometry methods. To deeper investigate the conformations adopted by such compounds in solution, we have carried out a molecular mechanic and dynamics calculation on amygdaloidin A and on the previously isolated euphodendroidin I. The data obtained gave further information on the endo- and exo-type conformations, the two main orientations of the jatrophane diterpenes.

The Mediterranean spurge Euphorbia characias L. afforded twelve new diterpenes based on a jatrophane skeleton named euphocharacins A-L. Their chemical structures were elucidated by extensive nuclear magnetic resonance and mass spectrometry methods. Euphocharacins A-L were tested as inhibitors of the daunomycin-efflux activity of P-glycoprotein from cancer cells. The results were used to extend the structure-activity relationship established for this class of compounds, highlighting the positive effects of propyl and benzoyl groups at positions 3 and 9, respectively, and evidencing the negative effect of a free hydroxyl group at position 2. Among the tested compounds, euphocharacins C and I showed an activity higher than cyclosporin to inhibit Pgp-mediated daunomycin transport.The Mediterranean spurge Euphorbia characias L. afforded twelve new diterpenes based on a jatrophane skeleton named euphocharacins A-L. Their chemical structures were elucidated by extensive nuclear magnetic resonance and mass spectrometry methods. Euphocharacins A-L were tested as inhibitors of the daunomycin-efflux activity of P-glycoprotein from cancer cells. The results were used to extend the structure-activity relationship established for this class of compounds, highlighting the positive effects of propyl and benzoyl groups at positions 3 and 9, respectively, and evidencing the negative effect of a free hydroxyl group at position 2. Among the tested compounds, euphocharacins C and I showed an activity higher than cyclosporin to inhibit Pgp-mediated daunomycin transport.

A new enzyme, S-adenosyl-l-methionine:flavonoid 4'-O-methyltransferase (EC 2.1.1.-) (F 4'-OMT), has been purified 1 399-fold from the tissues of carnation (Dianthus caryophyllus L). The enzyme, with a molecular mass of 43-45 kDa and a pI of 4.15, specifically methylates the hydroxy substituent in 4'-position of the flavones, flavanones and isoflavones in the presence of S-adenosyl-l-methionine. A high affinity for the flavone kaempferol was observed (Km = 1.7 micro m; Vmax = 95.2 micro mol.min-1.mg-1), while other 4'-hydroxylated flavonoids proved likewise to be suitable substrates. Enzyme activity had no apparent Mg++ requirement but was inhibited by SH-group reagents. The optimum pH value for F 4'-OMT activity was found to be around neutrality. Kinetic analysis of the enzyme bi-substrate reaction indicates a Ping-Pong mechanism and excludes the formation of a ternary complex. The F 4'-OMT activity was increased, in both in vitro and in vivo carnation tissues, by the inoculation with Fusarium oxysporum f. sp. dianthi. The enzyme did not display activity towards hydroxycinnamic acid derivatives, some of which are involved, as methylated monolignols, in lignin biosynthesis; the role of this enzyme could be therefore mainly defensive, rather than structural, although its precise function still needs to be ascertained.

Investigation of polar extracts from ripe fruits of Capsicum annuum L. var. acuminatum yielded three new glycosides, capsosides A (1) and B (2) and capsianoside VII (3), along with seven known compounds (4-10). The chemical structures were elucidated mainly by extensive nuclear magnetic resonance methods and mass spectrometry, and the biological activities of icariside E(5) (4) were tested by different assays. Icariside E(5), in contrast to capsaicin, neither induces an increase in the intracellular levels of reactive oxygen species nor affects the mitochondria permeability transition, and it does not signal through the vanilloid receptor type 1. Interestingly, this compound protects Jurkat cells from apoptosis induced by the oxidative stress mediated by serum withdrawal. These results suggest that icariside E(5) may have antioxidant properties that strengthen the importance of peppers in the Mediterranean diet.

From the fruit body of the fungus Marasmius oreades ( family Tricholomataceae ), 4,4-dimethyl-5αergosta-8,24(28)-dien-3β-ol (bd1), probably a biogenetic precursor of ergosterol, has been isolated along with ergosterol. Its stereostructure has been established unequivocally by spectroscopic methods, including 13 C nuclear magnetic resonance .

The bioactive metabolites of someAllium plants, all exhibiting interesting pharmacological activities, were tested for their attractive/repellent activity against saw-toothed grain beetle,Oryzaephilus surinamensis (L.), rice weevil,Sitophilus oryzae (L.), and rust-red flour beetle,Tribolium castaneum (Herbst), insects infesting the stored-products.

Two new sesterterpenes, lintenolides F ( 6 a, b ) and G ( 7 a, b ), were isolated from the Caribbean sponge Cacospongia cf. linteiformis . Their stereostructures were determined using spectroscopic and chemical methods. The new compounds ( 6 a, b and 7 a, b ) and the related compounds lintenolides A–E ( 1 a, b–5 a, b ), previously isolated from the sponge, exhibited antiproliferative activity on four cell lines.

From wild garlic Allium ursinum three new flavonoid glycosides were identified as kaempferol 3-O- β-neohesperidoside -7-O-[2-O-(trans-p- coumaroyl)]-β- d -glucopyranoside , kaempferol 3-O- β-neohesperidoside -7-O-[2-O-(trans- feruloyl)]-β- d -glucopyranoside , kaempferol 3-O- β-neohesperidoside -7-O-[2-O-(trans-p- coumaroyl )-3-O- β- d -glucopyranosyl]-β- d -glucopyranoside and characterized as the peracetates. Additionally, two known flavonoid glycosides kaempferol 3- O -β-glucopyranoside and kaempferol 3- O -neohesperidoside were isolated. The isolated compounds showed an inhibition of human platelet aggregation.

The red-pigmented caribbean sponge Thorecta horridus contains thorexanthin (3-methoxy-β-X-caroten-4-one) as a new carotenoid pigment. Its structure was determined by spectroscopic methods, including 2 D NMR experiments.

Polar lipid extract from the haloalkaliphilic archaebacterium Natronococcus occultus contains a new type of phospholipid. Spectroscopic methods establish the structure as a phosphatidylglycerol phosphate derivative with a cyclic phasphate (2,3-di-O-phytanyl-sn-glycero-1-phosphoryl-3′-sn-glycero-1′,2′-cyclic phosphate). A 2-O-sesterterpanyl-3-O-phytanyl (C25,C20) glycerol diether form of the novel phospholipid is also present.

Archaebacterial glycerol-bisdiphytanyl-glycerol tetraether core lipids containing from one to eight cyclopentane rings could be resolved from each other and from the parent uncyclized C40, C40 lipid by TLC. The core lipids of examples from the genera Methanobacterium, Methanobrevibacter, Methanogenium and Methanoplanus did not contain cyclized forms of glycerol-bisdiphytanyl-glycerol tetraethers, whereas the core lipids of Methanosarcina barkeri contained glycerol-bisdiphytanyl-glycerol tetraethers with from one to three cyclopentane rings in each C40 isopranoid chain.