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Pinarosa Avato
Ruolo
Professore Ordinario
Organizzazione
Università degli Studi di Bari Aldo Moro
Dipartimento
DIPARTIMENTO DI FARMACIA-SCIENZE DEL FARMACO
Area Scientifica
AREA 05 - Scienze biologiche
Settore Scientifico Disciplinare
BIO/14 - Farmacologia
Settore ERC 1° livello
Non Disponibile
Settore ERC 2° livello
Non Disponibile
Settore ERC 3° livello
Non Disponibile
ntroduction - Thapsia spp. (Apiaceae) are the major natural source of polyoxygenated guaianolide sesquiterpene lactones known as thapsigargins, which induce apoptosis in mammalian cells via a high affinity inhibition of the sarco/endoplasmic reticulum Ca(2+) ATPase. The mechanism of biosynthesis of thapsigargins has not been elucidated, and probable biochemical precursors such as hydrocarbon or oxygenated sesquiterpenes have not been identified in previous phytochemical analyses of essential oils from this genus. Objective - To investigate the utility of solid phase micro-extraction (SPME), when compared with classical essential oil distillates, for identifying potential precursors of guaianolide sesquiterpene lactones from Thapsia garganica L. and Thapsia villosa L. type II. Methodology - A systematic description of the volatile components of roots, flowers, stems and fruits of T. villosa and of root, flower and fruits of T. garganica was constructed via GC-MS analyses of SPME-adsorbed compounds and of essential oils obtained through hydrodistillation of the same tissues. Results - The sesquiterpenoids delta-cadinene, alpha- and delta-guaiene, elemol and guaiols were found to be major volatile constituents of the roots of T. garganica and T. villosa trapped using SPME. In contrast, these sesquiterpenoids were not detected or were at negligible levels in essential oils, where sesquiterpenoids are potentially converted to azulenes during hydrodistillation. Conclusion - The new data reported in this study demonstrates that SPME is a valuable tool for the identification of volatile sesquiterpenes when compared with analysis of essential oils, and we postulate that guaiene is the likely precursor of guaianolide sesquiterpenes from Thapsia.
Saponins from Medicago species are glycosidic compounds with an aglycone moiety formed through the enzymatic cyclization of 2,3-oxidosqualene by the beta-amyrin cyclase. All the saponins from Medicago genus possess the triterpenic pentacyclic nucleus belonging to the class of beta-amyrin. The so formed beta-amyrin skeleton can be further modified by oxidative reactions, mediated by cytochromes belonging to the class of cytochrome P450, to give different saponin compounds, characterized by the presence of hydroxyl or carboxyl groups located in specific positions of the triterpenic skeleton. Based on the position and the oxidation degree of the substituents, it is possible to distinguish two groups of saponins (sapogenins) in Medicago spp: (1) sapogenins possessing an OH group on C-24 (soyasapogenols A, B and E) without any substituent at the C-28 atom, and (2) sapogenins possessing the COOH group at C-28 that are associated with different oxidation degrees (zero, OH, CHO, COOH) at C-23. These results seem to indicate that the oxidation at C-24 and the presence of the COOH group at C-28 are mutually exclusive. The subdivision in the aglycone moiety is reflected also in the sugar moiety, operated by glycosyltranferases, as the saponins of the two groups differ for the position and the nature of the sugar chains. Based on these findings, new considerations on the biosynthesis of saponins in the genus Medicago can be drawn and a biosynthetic scheme is proposed.
The present work reports on the biological activity of alfalfa (Medicago sativa) saponins on white poplar (Populus alba, cultivar 'Villafranca') cell suspension cultures. The extracts from alfalfa roots, aerial parts and seeds were characterized for their saponin content by means of thin layer chromatography (TLC) and electrospray ionisation coupled to mass spectrometry. The quantitative saponin composition from the different plant extracts was determined considering the aglycone moieties and determined by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) analyses. Only soyasapogenin I was detected in the seed extract while several other saponins were found in the root and leaf extracts. Actively proliferating white poplar cell cultures were challenged with the different saponin extracts. Only alfalfa root saponins, at 50 mu g ml-1, induced significant cell death rates (75.00 +/- 4.90%). Different cell subpopulations with peculiar cell death morphologies were observed and the programmed cell death (PCD)/necrosis ratio was reduced at increasing saponin concentrations. Enhancement of nitric oxide (NO) production was observed in white poplar cells treated with root saponins (RSs) at 50 mu g ml-1 and release of reactive oxygen species (ROS) in the culture medium was also demonstrated. Saponin-induced NO production was sensitive to sodium azide and NG-monomethyl-l-arginine, two specific inhibitors of distinct pathways for NO biosynthesis in plant cells.
The genus Lavandula includes about thirty species plus a number of intraspecific taxa and hybrids, which are distributed in the Mediterranean area. The traditional use of lavender both as perfume or medicinal plant is known since antiquity. Nowadays several species are extensively cultivated for the extraction of their essential oils (EOs) which are used in manufactured products like cosmetics and perfumes or in phytotherapy. Lavandula pinnata L. f. (syn L. pinnata Lundmark) is a rare species native to the Canary Islands used in folk medicine as relaxant and also a valuable remedy against bites. To the best of our knowledge, EOs from L. pinnata have been very little studied. The present paper reports on the quali- and quantitative compositional profile of the EOs distilled (by a Spring type apparatus) from the aerial parts (flowers and leaves) of this species cultivated in soilless conditions. Chemical analyses by means of GC and GC-MS techniques have indicated that oxygenated monoterpenes are the main constituents of both the flowers (68.30%) and the leaves (83.65%). Carvacrol is the main compound which characterizes the EOs of this species. In addition, discrete amounts of spathulenol (12.22%) and caryophyllene oxide (14.62%) have been detected in flowers EOs, while leaves EOs contained small amounts of carvacrol methyl ether (2.52%).
Medicago sativa L., alfalfa, is the most known plant species within the Medicago genus. The plant has been extensively studied for its content of saponins, mainly consisting of triterpene glycosides of medicagenic acid, possessing several biological properties including a biocidal activity on different soil microorganisms. Phytoparasitic nematodes are responsible for heavy economic damages to numerous agricultural crops and, due to their large distribution, they are among the most difficult crop pests to control. Attention on environmental safety and human and animal health has led to the progressive dismission of many synthetic formulations for the control of those pests and to the search of alternative strategies, including the use of natural metabolites from plants. Saponins from M. sativa may be good candidates for natural nematicide formulations, as in our in vitro studies the saponin mixtures from M. sativa tissues have been found effective in vitro against the virus-vector nematode Xiphinema index, the root-knot nematode Meloidogyne incognita and the potato cyst parasite, Globodera rostochiensis. A structure-activity relationship among saponins and related prosapogenins and sapogenin, respectively, has also been analyzed. The nematicidal efficacy differed among the three assayed nematode species, G. rostochiensis being the most susceptible to the active compounds from alfalfa. The in vitro results were also confirmed by experiments in potting mixes infested by M. incognita or G. rostochiensis and amended with dry top and root material from M. sativa, and in field trials on M. incognita and carrot cyst nematode Heterodera carotae with M. sativa pelleted meal. All amendments reduced root and soil population densities of target nematode species compared to non-treated and chemical controls, with a general improvement of plant growth and yield performances.
In this paper we describe the morphological, histological and chemical characters of 20 native Helichrysum italicum (Roth) G. Don ssp. italicum genotypes collected from different locations in Italy and Corsica (France) and grown under similar edaphic and climatic conditions. An AFLP technique was used to examine the level of genetic variability among the genotypes with the aim to disclose a possible correlation between the genetic and chemical data. The chemical analysis recognizes at least three different chemotypes based on the major constituents in the essential oils. This was confirmed by the AFLP analysis resulting in a dendrogram divided into three main clades. Because of the polymorphic trait of Helichrysum species, an efficient micropropagation protocol was established for the 20 H. italicum (Roth) G. Don ssp. italicum genotypes to guarantee the availability of stable genetic material with defined chemical profiles for industrial applications. The genotypes were found to influence the in vitro performance and the chemical composition of the essential oils, but not the phenotypic traits of the plants.
Carvacrol is the major constituent of essential oils from aromatic plants. It showed antimicrobial, anticancer and antioxidant properties. Although it was approved for food use and included in the chemical flavorings list, no indication on its safety has been estimated. Since the use of plant extracts is relatively high among women, aim of this study was to evaluate carvacrol effects on female physiology and endocrine profiles by using female rats in proestrus and diestrus phases. Serotonin and metabolite tissue content in prefrontal cortex and nucleus accumbens, after carvacrol administration (0.15 and 0.45 g/kg p.o.), was measured. Drug effects in behavioral tests for alterations in motor activity, depression, anxiety-related behaviors and endocrine alterations were also investigated. While in proestrus carvacrol reduced serotonin and metabolite levels in both brain areas, no effects were observed in diestrus phase. Only in proestrus phase, carvacrol induced a depressive-like behavior in forced swimming test, without accompanying changes in ambulation. The improvement of performance in FST after subchronic treatment with fluoxetine (20 mg/kg) suggested a specific involvement of serotonergic system. No differences were found across the groups with regard to self-grooming behavior. Moreover, in proestrus phase, carvacrol reduced only estradiol levels without binding hypothalamic estradiol receptors. Our study showed an estrous-stage specific effect of carvacrol on depressive behaviors and endocrine parameters, involving serotonergic system. Given the wide carvacrol use not only as feed additive, but also as cosmetic essence and herbal remedy, our results suggest that an accurate investigation on the effects of its chronic exposure is warranted. (C) 2011 Elsevier Inc. All rights reserved.
Plants of the Brassicaceae family are widespread in the Mediterranean regions where they are widely consumed cooked (cauliflowers, broccoli, turnips) or as salads or condiments. These plants are a good source of bioactive compounds of nutraceutical relevance1,2. Among them the glucosinolates (GLS), responsible for the plant pungent aroma and bitter taste, are of particular interest. GLS are the most studied bioactive compounds in the Brassicaceae family and epidemiological studies have shown an inverse correlation between consumption of brassica plants and risk of cancer3. We have focused our attention on three Brassicaceae, B. oleracea, B. rapa, and Eruca sativa traditionally eaten in Puglia. The edible inflorescences of B.oleracea var italica, locally called “mugnolo” and traditionally cultivated in Salento, are characterized by the presence of the aliphatic GLSs glucoraphanin (1.79 μmol/g), glucoiberin, glucoerucin, and sinigrin, and by a good content of the aromatic GLSs glucobarberin (0.56 μmol/g) and gluconasturtin, and of the indole GLSs glucobrassicin (3.51 μmol/g), neoglucobrassicin, 4-methoxyglucobrassicin, and 4- hydroxyglucobrassicin2. In the leaves of Eruca sativa, particularly consumed as salad, the most abundant GLS is glucoraphanin. In the aerial parts of B.rapa there are three predominant GLSs: two indole GLS neoglucobrassicin (1.65 μmol/g) and glucobrassicin (0.97 μmol/g) and the aliphatic GLS gluconapin (1.13 μmol/g). Given the importance of Brassicaceae for their content in GLSs, we have also studied the accumulation of these metabolites during the different stages of growth taken B. rapa as plant model. The aerial parts of B. rapa have been found to contain more GLS during the budding stage. Moreover we have observed that at budding indole GLSs are dominant while at flowering there are more aliphatic GLSs. This gives an added value to B. rapa since it’s known that hydrolysis products from the indole GLSs have anticarcinogenic properties by induction of phase I or phase II detoxification enzymes4.
Glucosinolates (GLSs) from a variety of Brassica oleracea, known locally as "mugnolo" and widely distributed in southern Italy, were studied. It was found that "mugnolo" inflorescences are characterized by the presence of the aliphatic GLSs glucoraphanin (1.79 mu mol/g), glucoiberin, glucoerucin, and sinigrin, of the aromatic GLSs glucobarberin (0.56 mu mol/g) and gluconasturtin, and of the indole GLSs glucobrassicin (3.51 mu mol/g), neoglucobrassicin, 4-methoxyglucobrassicin, and 4-hydroxyglucobrassicin. Indole GLSs were predominant, while aliphatic and aromatic GLS were found in lower quantities. The metabolic profile of "mugnolo" leaves was also studied. It was found that 4-hydroxyglucobrassicin (0.13 mu mol/g) and glucoraphanin (0.11 mu mol/g)are the predominant GLSs. Vegetables of the Brassicaceae family are seldom consumed raw; therefore we also analyzed the GLS profile of "mugnolo" after cooking in water. The results showed variations in the GLSs content with a fall in concentration of 50%.
Brassicaceae Burnett (syn. Cruciferae A. L. de Jussieu) include many important economic plants used as edibile or ornamental. They are commonly known as the “mustard” plant family due to the sharp, potent flavour of their main metabolites, the glucosinolates (GLSs) which contain sulfur. Glucosinolates coexist in vivo with glycosylated thioglucosidases, myrosinase(s), responsible of their hydrolysis with the production of bioactive cognate isothiocyanates (ITC). GLSs and ITCs function as defence bioactive metabolites against plant pathogens, insects and herbivores. The present review paper focus on GLSs role as bionematicides. The current knowledge on the efficacy of these phytochemicals against the most common phytoparasitic nematodes affecting crops of agriculture importance such as tomato, potato and grapevine is reported. Data from our ongoing research on the in vitro biocidal activity of glucosinolate extracts, and their main components, against the virus-vector nematode Xiphinema index Thorne & Allen and the carrot cyst nematode Heterodera carotae Jones are also described.
The paper describes the flavonoid composition of the aerial parts (young leaves, YL; adult leaves, AL; stems, ST) of Passiflora loefgrenii Vitta, a rare species native to Brazil, where it is traditionally used as food. Antioxidant potential has also been evaluated. To the best of our knowledge, no phytochemical and biological study on this species has been reported previously.
Abstract Strategies to control diffusion of malaria needs to account for the increase of resistance of the parasite to the conventional antimalarial drugs. It has been proposed that a traditional aqueous preparation from Artemisia annua, with a low content of the active compound, artemisinin, may reduce the risk of resistance of the protozoa and be relatively more effective in the treatment of the disease. The solubility properties of the molecule have been the matter of concern about the therapeutic usefulness of herbal teas from A. annua. The present study aimed at analysing the chemical profile of a tea infusion from A. annua. Tea from A. annua was prepared through infusion of the plant aerial parts in water for 1, 24 and 48 h. Content of artemisinin was determined by HPLC-ELSD. Overall chemical characterization of the extracts was carried out by a combination of metabolomic techniques. The artemisinin content varied only slightly in the three different extracts (about 0.12%). A series of mono-caffeoyl- and mono-feruloyl-quinic acids, di-caffeoyl- and di-feruloyl-quinic acids was identified as main components of the tea infusion, together with some flavonoids. Reconstitution of the same extracts in less polar or apolar solvents resulted in a different composition with no phenolics and a much lower concentration of artemisinin.
plants of Capparales (or Brassicales) are widespread in the Mediterranean region where they are widely consumed cooked or as salad vegetables (cabbage, Brussels sprouts, cauliflower, broccoli) or as condiments (horseradish, mustard, capers). these plants are a good source of bioactive compounds such as glucosinolates, vitamins, flavonoids, minerals. glucosinolates are responsible for pungent and bitter taste of Brassicaceae and are the most extensively studied bioactive compounds for their potential as anticarcinogens due to their hydrolysis products, the isothiocyanates. this study describes the chemical profile of a poorly studied variety of Brassica oleracea, traditionally cultivated in Southern italy and locally called “mugnolo”, and of Capparis spinosa subsp rupestris. it was found that “mugnolo” inflorescences are characterized by aliphatic, aromatic and indole glucosinolates. among them the indole glucosinolates (7.68 μmol/g) are predominant, while aliphatic and aromatic glucosinolates are found in low quantities, 2.63 μmol/g and 0.83 μmol/g respectively. chemical composition of seeds and aerial parts of C. spinosa subsp rupestris was also determined. it was found that the principal glucosinolate of the seeds is the glucocapparin, moreover the seeds oil is rich in unsaturated and rare lipids such as cis-vaccenic acid. the aerial parts are characterized by rutin as predominant flavonoid.
The saponin composition of leaves from the Medicago polymorpha cultivars 'Santiago' and 'Anglona' belonging to the botanical varieties brevispina and vulgaris, respectively, was investigated by a combination of chromatographic, spectroscopic, and spectrometric techniques. Several compounds were detected and quantitated by HPLC analysis using the external standard method. Twelve triterpene saponins (1-12) were purified by reverse-phase chromatography and their structures elucidated by spectroscopic (1D and 2D NMR, ESI-MS/MS) and chemical methods. They were identified as glycosides of echinocystic acid, hederagenin, caulophyllogenin, bayogenin, and soyasapogenol B. Two of them (2, 10) were previously reported in M. polymorpha; five of them (4, 6, 7, 9, 12) were already identified in other Medicago species; and three of them (1, 8, 11) were found in other plant genera. The two saponins identified as 3-O-alpha-L-arabinopyranosyl-28-O-[beta-D-glucopyranosyl(1 -> 6)beta-D-glucopyranoside] echinocystic acid (3) and 3-O-alpha-L-arabinopyranosyl-28-O-beta-D-glucopyranoside echinocystic acid (5) are newly identified natural compounds. The presence of echinocystic acid is reported here for the first time in the genus Medicago. Saponins from the cultivar 'Anglona' were characterized by a higher amount of echinocystic acid glycosydes, whereas saponins from the cultivar 'Santiago' were characterized by a higher amount of hederagenin glycosydes.
Vitis vinifera cv. uvalino is an old native grape vine from Piedmont which has been recently rediscovered for the production of wine. Chemical studies have shown that the cultivar has the highest content of resveratrol (Borsa D. et al 2003) which is consistent with the high antioxidant activity displayed in in vitro experiments (Bertelli A. et al 2004). As a continuation of the chemical study on Vitis vinifera cv. uvalino we aimed to characterize the composition of the oil from its seeds. Grape seeds are considered to be a left-over product from the wine making process whose utilization is however of economic relevance for waste reduction. Grape seed oil, “olio di vinaccioli”, is a high-quality edible oil with beneficial health properties mainly due to its content of unsaturated fatty acids. In our study, chemical profiling of the seed oil from V. vinifera cv uvalino has been obtained by a combination of spectrometric and spectroscopic techniques such as GC, GC-MS, NMR and ESI-MS/MS. Uvalino’s grape seed oil was found to consist of triacylglycerols (TAG) as in the case of seed oils from other grape cultivars (Bail S. et al 2008). Analysis of TAG fatty acid composition indicated that the two unsaturated linoleic acid (72.87 %) and oleic acid (13.20%) are dominant, whereas palmitic acid (9.59%) is the most abundant saturated fatty acid. Moreover, ESI-MS/MS allowed to disclose the most abundant TAG species which include components at m/z 901 (OLO), 898 (LLL) and 877 (LSP). In addition to the above, an analytical method based on HPLC-ELSD detection has been developed for identification of TAG species in grape seed oils and it will be presented here.
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