sábado, 13 de agosto de 2016

The Interference of Selected Cytotoxic Alkaloids with the Cytoskeleton: An Insight into Their Modes of Action

Alkaloids, the largest group among the nitrogen-containing secondary metabolites of plants, usually interact with several molecular targets. In this study, we provide evidence that six cytotoxic alkaloids (sanguinarine, chelerythrine, chelidonine, noscapine, protopine, homoharringtonine), which are known to affect neuroreceptors, protein biosynthesis and nucleic acids, also interact with the cellular cytoskeleton, such as microtubules and actin filaments, as well. Sanguinarine, chelerythrine and chelidonine depolymerized the microtubule network in living cancer cells (Hela cells and human osteosarcoma U2OS cells) and inhibited tubulin polymerization in vitro with IC50 values of 48.41 ± 3.73, 206.39 ± 4.20 and 34.51 ± 9.47 μM, respectively. However, sanguinarine and chelerythrine did not arrest the cell cycle while 2.5 μM chelidonine arrested the cell cycle in the G2/M phase with 88.27% ± 0.99% of the cells in this phase. Noscapine and protopine apparently affected microtubule structures in living cells without affecting tubulin polymerization in vitro, which led to cell cycle arrest in the G2/M phase, promoting this cell population to 73.42% ± 8.31% and 54.35% ± 11.26% at a concentration of 80 μM and 250.9 μM, respectively. Homoharringtonine did not show any effects on microtubules and cell cycle, while the known microtubule-stabilizing agent paclitaxel was found to inhibit tubulin polymerization in the presence of MAPs in vitro with an IC50 value of 38.19 ± 3.33 μM. Concerning actin filaments, sanguinarine, chelerythrine and chelidonine exhibited a certain effect on the cellular actin filament network by reducing the mass of actin filaments. The interactions of these cytotoxic alkaloids with microtubules and actin filaments present new insights into their molecular modes of action.
Wang, X.; Tanaka, M.; Krstin, S.; Peixoto, H.S.; Wink, M. The Interference of Selected Cytotoxic Alkaloids with the Cytoskeleton: An Insight into Their Modes of Action. Molecules 2016, 21, 906.

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Solving a plant-based Rubik's cube puzzle

Date: July 15, 2016

Source: John Innes Centre

Summary:
A key 'twist' in a Rubik's cube-like plant puzzle has been discovered by scientists. This find could pave the way to new, or more effective pharmaceuticals, they say.

In previous work the research team showed that an enzyme called THAS is involved in taking a precursor molecule called strictosidine aglycone (SA) and converting it into the heteroyohimbine molecule tetrahydroalstonine. The group explored the transcriptome of the flowering plant Catharanthus roseus (Madagascar Periwinkle), a known source of tetrahydroalstonine, and found 14 candidate enzymes with very similar sequences to THAS.
Credit: The John Innes Centre

Scientists at the John Innes Centre have discovered a key "twist" in a Rubik's cube-like plant puzzle, which could pave the way to new, or more effective pharmaceuticals.

Several members and derivatives of a group of natural plant compounds called heteroyohimbines, are, or have potential to be, important in medicine. One called ajmalicine, for example, is used as a treatment for high blood pressure, and the oxidised alstonine shows promise as an anti-psychotic drug. Piecing together the puzzle of how these compounds are made in plants could have enormous potential for developing new and improved therapies.

But the heteroyohimbine puzzle is not a simple jigsaw in which the picture becomes clearer with each new piece discovered; it's more like a Rubik's cube. New research, published in Nature Communications by researchers working in Professor Sarah O'Connor's laboratory at the John Innes Centre, reveals a crucial "twist" in the puzzle that could make the rest easier to solve.

Dr Evangelos Tatsis, a postdoctoral researcher at the John Innes Centre, and a first author of the work along with PhD student Anna Stavrinides, said, "The small group of heteroyohimbines are all stereoisomers of each other, that is, they all have the same molecular formula, but they differ in the way their atoms are arranged -- just like a Rubik's cube has the same number of coloured squares, but the way you twist the cube gives different patterns. Different stereoisomers have different biological activities, so we have been trying to understand how those different conformations arise, and why."

In previous work the research team showed that an enzyme called THAS is involved in taking a precursor molecule called strictosidine aglycone (SA) and converting it into the heteroyohimbine molecule tetrahydroalstonine. However, it was not known how or why the different stereoisomers formed.

As a starting point, the group explored the transcriptome of the flowering plant Catharanthus roseus (Madagascar Periwinkle), a known source of tetrahydroalstonine, and found 14 candidate enzymes with very similar sequences to THAS. The scientists then expressed each of these enzymes in a different bacterial colony 'fed' with SA, and compared them to see which heteroyohimbines were produced.

Heteroyohimbine compounds were produced in four of the 14 experiments. In three of these, production of the heteryohimbines tetrahydroalstonine and mayumbine was very similar: a ratio of 85:15. The fourth enzyme, called HYS, gave a completely different production profile of ajmalicine, tetrahydroalstonine and mayumbine in a ratio of 55:27:15.

Dr Tatsis said, "Each of our four candidate enzymes had very similar structures, and each was given the same substrate to start with. But, one of them produced different heteroyohimbines in different amounts -- why? By resolving the crystal structures of these four enzymes, we determined what was different about HYS, and found that a particular loop of amino acid sequence is important in producing these different stereoisomers."

Conversion of SA into different heteroyohimbines seems to be a critical 'branching point' -- after this, derivative 'scaffolds' can be further altered by other enzymes to produce a whole suite of alkaloid products with potentially useful and valuable properties.

The discovery of HYS, along with systems recently developed at the John Innes Centre to produce plant compounds in large quantities, means we might be able to not only solve this Rubik's cube-like puzzle, but perhaps engineer improved or completely new compounds for use in medicine.

Story Source:

The above post is reprinted from materials provided by John Innes Centre.Note: Content may be edited for style and length.

Journal Reference:
Anna Stavrinides, Evangelos C. Tatsis, Lorenzo Caputi, Emilien Foureau, Clare E. M. Stevenson, David M. Lawson, Vincent Courdavault, Sarah E. O'Connor. Structural investigation of heteroyohimbine alkaloid synthesis reveals active site elements that control stereoselectivity. Nature Communications, 2016; 7: 12116 DOI:10.1038/ncomms12116

Cite This Page:
John Innes Centre. "Solving a plant-based Rubik's cube puzzle." ScienceDaily. ScienceDaily, 15 July 2016. <www.sciencedaily.com/releases/2016/07/160715112708.htm>.

Date: July 15, 2016 Source: John Innes Centre Summary: A key 'twist' in a Rubik's cube-like plant puzzle has been discovered by scientists. This find could pave the way to new, or more effective pharmaceuticals, they say.

Date: July 15, 2016

Source: John Innes Centre

Summary:
A key 'twist' in a Rubik's cube-like plant puzzle has been discovered by scientists. This find could pave the way to new, or more effective pharmaceuticals, they say.
In previous work the research team showed that an enzyme called THAS is involved in taking a precursor molecule called strictosidine aglycone (SA) and converting it into the heteroyohimbine molecule tetrahydroalstonine. The group explored the transcriptome of the flowering plant Catharanthus roseus (Madagascar Periwinkle), a known source of tetrahydroalstonine, and found 14 candidate enzymes with very similar sequences to THAS.
Credit: The John Innes Centre

Scientists at the John Innes Centre have discovered a key "twist" in a Rubik's cube-like plant puzzle, which could pave the way to new, or more effective pharmaceuticals.

Several members and derivatives of a group of natural plant compounds called heteroyohimbines, are, or have potential to be, important in medicine. One called ajmalicine, for example, is used as a treatment for high blood pressure, and the oxidised alstonine shows promise as an anti-psychotic drug. Piecing together the puzzle of how these compounds are made in plants could have enormous potential for developing new and improved therapies.

But the heteroyohimbine puzzle is not a simple jigsaw in which the picture becomes clearer with each new piece discovered; it's more like a Rubik's cube. New research, published in Nature Communications by researchers working in Professor Sarah O'Connor's laboratory at the John Innes Centre, reveals a crucial "twist" in the puzzle that could make the rest easier to solve.

Dr Evangelos Tatsis, a postdoctoral researcher at the John Innes Centre, and a first author of the work along with PhD student Anna Stavrinides, said, "The small group of heteroyohimbines are all stereoisomers of each other, that is, they all have the same molecular formula, but they differ in the way their atoms are arranged -- just like a Rubik's cube has the same number of coloured squares, but the way you twist the cube gives different patterns. Different stereoisomers have different biological activities, so we have been trying to understand how those different conformations arise, and why."

In previous work the research team showed that an enzyme called THAS is involved in taking a precursor molecule called strictosidine aglycone (SA) and converting it into the heteroyohimbine molecule tetrahydroalstonine. However, it was not known how or why the different stereoisomers formed.

As a starting point, the group explored the transcriptome of the flowering plant Catharanthus roseus (Madagascar Periwinkle), a known source of tetrahydroalstonine, and found 14 candidate enzymes with very similar sequences to THAS. The scientists then expressed each of these enzymes in a different bacterial colony 'fed' with SA, and compared them to see which heteroyohimbines were produced.

Heteroyohimbine compounds were produced in four of the 14 experiments. In three of these, production of the heteryohimbines tetrahydroalstonine and mayumbine was very similar: a ratio of 85:15. The fourth enzyme, called HYS, gave a completely different production profile of ajmalicine, tetrahydroalstonine and mayumbine in a ratio of 55:27:15.

Dr Tatsis said, "Each of our four candidate enzymes had very similar structures, and each was given the same substrate to start with. But, one of them produced different heteroyohimbines in different amounts -- why? By resolving the crystal structures of these four enzymes, we determined what was different about HYS, and found that a particular loop of amino acid sequence is important in producing these different stereoisomers."

Conversion of SA into different heteroyohimbines seems to be a critical 'branching point' -- after this, derivative 'scaffolds' can be further altered by other enzymes to produce a whole suite of alkaloid products with potentially useful and valuable properties.

The discovery of HYS, along with systems recently developed at the John Innes Centre to produce plant compounds in large quantities, means we might be able to not only solve this Rubik's cube-like puzzle, but perhaps engineer improved or completely new compounds for use in medicine.

Story Source:

The above post is reprinted from materials provided by John Innes Centre.Note: Content may be edited for style and length.

Journal Reference:
Anna Stavrinides, Evangelos C. Tatsis, Lorenzo Caputi, Emilien Foureau, Clare E. M. Stevenson, David M. Lawson, Vincent Courdavault, Sarah E. O'Connor. Structural investigation of heteroyohimbine alkaloid synthesis reveals active site elements that control stereoselectivity. Nature Communications, 2016; 7: 12116 DOI:10.1038/ncomms12116

Cite This Page:
John Innes Centre. "Solving a plant-based Rubik's cube puzzle." ScienceDaily. ScienceDaily, 15 July 2016. <www.sciencedaily.com/releases/2016/07/160715112708.htm>.

Molecular Approaches to Genetically Improve the Accumulation of Health-Promoting Secondary Metabolites in Staple Crops—A Case Study: The Lipoxygenase-B1 Genes and Regulation of the Carotenoid Content in Pasta Products

Secondary metabolites, also known as phytochemicals, represent a large subset of plant molecules that include compounds with health-promoting effects. Indeed, a number of epidemiological studies have shown that, when taken regularly and in adequate amounts, these molecules can have long-term beneficial effects on human health, through reduction of the incidence of degenerative diseases, such as cardiovascular diseases, obesity, diabetes, and cancer. As the dietary intake of these phytochemicals is often inadequate, various strategies are in use to improve their content in staple crops, and the end-products thereof. One of the most effective strategies is crop improvement through genetic approaches, as this is the only way to generate new cultivars in which the high accumulation of a given phytochemical is stably fixed. Efforts to genetically improve quality traits are rapidly evolving, from classical breeding to molecular-assisted approaches; these require sound understanding of the molecular bases underlying the traits, to identify the genes/alleles that control them. This can be achieved through global analysis of the metabolic pathway responsible for phytochemical accumulation, to identify the link between phytochemical content and the activities of key enzymes that regulate the metabolic pathway, and between the key enzymes and their encoding genes/alleles. Once these have been identified, they can be used as markers for selection of new improved genotypes through biotechnological approaches. This review provides an overview of the major health-promoting properties shown to be associated with the dietary intake of phytochemicals, and describes how molecular approaches provide means for improving the health quality of edible crops. Finally, a case study is illustrated, of the identification in durum wheat of the Lipoxygenase-B1 genes that control the final carotenoid content in semolina-based foods, such as pasta products.
Figure 1. Schematic representation of the biosynthesis of secondary metabolites. E4P, erythrose 4-phosphate; G3P, glyceraldehyde 3-phosphate; PEP, phosphoenolpyruvate; PYR, pyruvate; DOX5P, deoxyxylulose 5-phosphate; IPP, isopentenyl pyrophosphate; DMAPP, dimethylallyl pyrophosphate; PP, pyrophosphate; GPP, geranyl pyrophosphate; FPP, farnesyl pyrophosphate; GGPP, geranylgeranyl pyrophosphate.
Figure 5. Outline of how a functional approach can contribute to identification of a candidate gene associated with high levels of a health-promoting phytochemical in a staple crop. A germplasm collection is screened to determine the variability in nature of the trait. Genotypes characterized by contrasting metabolite accumulation are subjected to enzymatic analysis to identify key enzyme variants (i.e., allozymes) that are characterized by contrasting activities/efficiencies, and molecular analysis to identify alleles that encode the different allozymes and to evaluate their expression levels.

Then, on the basis of both the enzymatic and molecular information, a candidate gene/allele can be identified that can then be efficiently used in advanced breeding programs that are aimed at the introgression of the trait of interest into an elite cultivar.
Figure 6. Reaction catalyzed by lipoxygenase (LOX) during pasta processing. LOX catalyzes hydroperoxidation of free linoleate (LH), to give the corresponding hydroperoxide (LOOH). pasta processing the pentadienyl (L°) and peroxy radicals (LOO°) of linoleate oxidize the semolina carotenoid pigments, thus leading to carotenoid loss and discoloration of the end product.

Borrelli, G.M.; Trono, D. Molecular Approaches to Genetically Improve the Accumulation of Health-Promoting Secondary Metabolites in Staple Crops—A Case Study: The Lipoxygenase-B1 Genes and Regulation of the Carotenoid Content in Pasta Products. Int. J. Mol. Sci. 2016, 17, 1177.

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Food Antioxidants and Their Anti-Inflammatory Properties: A Potential Role in Cardiovascular Diseases and Cancer Prevention

Mediterranean-style diets caused a significant decline in cardiovascular diseases (CVDs) in early landmark studies. The effect of a traditional Mediterranean diet on lipoprotein oxidation showed that there was a significant reduction in oxidative stress in the intervention group (Mediterranean diet + Virgin Olive Oil) compared to the low-fat diet group. Conversely, the increase in oxidative stress causing inflammation is a unifying hypothesis for predisposing people to atherosclerosis, carcinogenesis, and osteoporosis. The impact of antioxidants and anti-inflammatory agents on cancer and cardiovascular disease, and the interventive mechanisms for the inhibition of proliferation, inflammation, invasion, metastasis, and activation of apoptosis were explored. Following the Great Oxygen Event some 2.3 billion years ago, organisms have needed antioxidants to survive. Natural products in food preservatives are preferable to synthetic compounds due to their lower volatility and stability and generally higher antioxidant potential. Free radicals, reactive oxygen species, antioxidants, pro-oxidants and inflammation are described with examples of free radical damage based on the hydroxyl, nitric oxide and superoxide radicals. Flavonoid antioxidants with 2- or 3-phenylchroman structures such as quercetin, kaempferol, myricetin, apigenin, and luteolin, constituents of fruits, vegetables, tea, and wine, which may reduce coronary disease and cancer, are described. The protective effect of flavonoids on the DNA damage caused by hydroxyl radicals through chelation is an important mechanism, though the converse may be possible, e.g., quercetin. The antioxidant properties of carotenoids, which are dietary natural pigments, have been studied in relation to breast cancer risk and an inverse association was found with plasma concentrations: higher levels mean lower risk. The manipulation of primary and secondary human metabolomes derived especially from existing or transformed gut microbiota was explored as a possible alternative to single-agent dietary interventions for cancer and cardiovascular disease. Sustained oxidative stress leading to inflammation and thence to possibly to cancer and cardiovascular disease is described for spices and herbs, using curcumin as an example of an intervention, based on activation of transcription factors which suggest that oxidative stress, chronic inflammation, and cancer are closely linked.
Figure 1. An example of isoflavonoid production by gut microflora (with the kind permission of David Griffiths, Castleton, Gwent).
Figure 2. Flavonoid polyphenols, catechins, isolated from green tea (with the kind permission of David Griffiths, Castleton, Gwent).

Griffiths, K.; Aggarwal, B.B.; Singh, R.B.; Buttar, H.S.; Wilson, D.; De Meester, F. Food Antioxidants and Their Anti-Inflammatory Properties: A Potential Role in Cardiovascular Diseases and Cancer Prevention. Diseases 2016, 4, 28.

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Nutraceutical Improvement Increases the Protective Activity of Broccoli Sprout Juice in a Human Intestinal Cell Model of Gut Inflammation

Benefits to health from a high consumption of fruits and vegetables are well established and have been attributed to bioactive secondary metabolites present in edible plants. However, the effects of specific health-related phytochemicals within a complex food matrix are difficult to assess. In an attempt to address this problem, we have used elicitation to improve the nutraceutical content of seedlings of Brassica oleracea grown under controlled conditions. Analysis, by LC-MS, of the glucosinolate, isothiocyanate and phenolic compound content of juices obtained from sprouts indicated that elicitation induces an enrichment of several phenolics, particularly of the anthocyanin fraction. To test the biological activity of basal and enriched juices we took advantage of a recently developed in vitro model of inflamed human intestinal epithelium. Both sprouts’ juices protected intestinal barrier integrity in Caco-2 cells exposed to tumor necrosis factor α under marginal zinc deprivation, with the enriched juice showing higher protection. Multivariate regression analysis indicated that the extent of rescue from stress-induced epithelial dysfunction correlated with the composition in bioactive molecules of the juices and, in particular, with a group of phenolic compounds, including several anthocyanins, quercetin-3-Glc, cryptochlorogenic, neochlorogenic and cinnamic acids.

Ferruzza, S.; Natella, F.; Ranaldi, G.; Murgia, C.; Rossi, C.; Trošt, K.; Mattivi, F.; Nardini, M.; Maldini, M.; Giusti, A.M.; Moneta, E.; Scaccini, C.; Sambuy, Y.; Morelli, G.; Baima, S. Nutraceutical Improvement Increases the Protective Activity of Broccoli Sprout Juice in a Human Intestinal Cell Model of Gut Inflammation. Pharmaceuticals 2016, 9, 48.
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HERBOLISTERIA: EL CEDRON DE PALO, CULTIVO, CUIDADOS Y UTILIDAD

HiERBA LUiSA - Cultivo, Propiedades, Beneficios y Contraindicaciones

Cultivo de plantas medicinais no IFRJ - Campus Pinheiral

Anti-Adhesive Activity of Cranberry Phenolic Compounds and Their Microbial-Derived Metabolites against Uropathogenic Escherichia coli in Bladder Epithelial Cell Cultures

Cranberry consumption has shown prophylactic effects against urinary tract infections (UTI), although the mechanisms involved are not completely understood. In this paper, cranberry phenolic compounds and their potential microbial-derived metabolites (such as simple phenols and benzoic, phenylacetic and phenylpropionic acids) were tested for their capacity to inhibit the adherence of uropathogenic Escherichia coli (UPEC) ATCC®53503™ to T24 epithelial bladder cells. Catechol, benzoic acid, vanillic acid, phenylacetic acid and 3,4-dihydroxyphenylacetic acid showed anti-adhesive activity against UPEC in a concentration-dependent manner from 100–500 µM, whereas procyanidin A2, widely reported as an inhibitor of UPEC adherence on uroepithelium, was only statistically significant (p < 0.05) at 500 µM (51.3% inhibition). The results proved for the first time the anti-adhesive activity of some cranberry-derived phenolic metabolites against UPEC in vitro, suggesting that their presence in the urine could reduce bacterial colonization and progression of UTI.

González de Llano, D.; Esteban-Fernández, A.; Sánchez-Patán, F.; Martínlvarez, P.J.; Moreno-Arribas, M.V.; Bartolomé, B. Anti-Adhesive Activity of Cranberry Phenolic Compounds and Their Microbial-Derived Metabolites against Uropathogenic Escherichia coliin Bladder Epithelial Cell Cultures. Int. J. Mol. Sci. 2015, 16, 12119-12130.
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Ginseng Metabolites on Cancer Chemoprevention: An Angiogenesis Link?

Cancer is a leading cause of death in the United States. Angiogenesis inhibitors have been introduced for the treatment of cancer. Based on the fact that many anticancer agents have been developed from botanical sources, there is a significant untapped resource to be found in natural products. American ginseng is a commonly used herbal medicine in the U.S., which possesses antioxidant properties. After oral ingestion, natural ginseng saponins are biotransformed to their metabolites by the enteric microbiome before being absorbed. The major metabolites, ginsenoside Rg3 and compound K, showed significant potent anticancer activity compared to that of their parent ginsenosides Rb1, Rc, and Rd. In this review, the molecular mechanisms of ginseng metabolites on cancer chemoprevention, especially apoptosis and angiogenic inhibition, are discussed. Ginseng gut microbiome metabolites showed significant anti-angiogenic effects on pulmonary, gastric and ovarian cancers. This review suggests that in addition to the chemopreventive effects of ginseng compounds, as angiogenic inhibitors, ginsenoside metabolites could be used in combination with other cancer chemotherapeutic agents in cancer management.


Wang, C.-Z.; Cai, Y.; Anderson, S.; Yuan, C.-S. Ginseng Metabolites on Cancer Chemoprevention: An Angiogenesis Link?Diseases 2015, 3, 193-204.
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Phthalate Metabolites, Consumer Habits and Health Effects

Phthalates are multifunctional chemicals used in a wide variety of consumer products. The aim of this study was to investigate whether levels of urinary phthalate metabolites in urine samples of Austrian mothers and their children were associated with consumer habits and health indicators. Within an Austrian biomonitoring survey, urine samples from 50 mother-child pairs of five communities (two-stage random stratified sampling) were analysed. The concentrations of 14 phthalate metabolites were determined, and a questionnaire was administered. Monoethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), monobenzyl phthalate (MBzP), mono-(2-ethylhexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), mono-(2-ethyl-5-oxohexyl) phthalate (5oxo-MEHP), mono-(5-carboxy-2-ethylpentyl) phthalate (5cx-MEPP), and 3-carboxy-mono-propyl phthalate (3cx-MPP) could be quantified in the majority of samples. Significant correlations were found between the use of hair mousse, hair dye, makeup, chewing gum, polyethylene terephthalate (PET) bottles and the diethyl phthalate (DEP) metabolite MEP. With regard to health effects, significant associations of MEP in urine with headache, repeated coughing, diarrhoea, and hormonal problems were observed. MBzP was associated with repeated coughing and MEHP was associated with itching.

Wallner, P.; Kundi, M.; Hohenblum, P.; Scharf, S.; Hutter, H.-P. Phthalate Metabolites, Consumer Habits and Health Effects. Int. J. Environ. Res. Public Health 2016, 13, 717.

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Fungal Metabolites for the Control of Biofilm Infections

Many microbes attach to surfaces and produce a complex matrix of polymers surrounding their cells, forming a biofilm. In biofilms, microbes are much better protected against hostile environments, impairing the action of most antibiotics. A pressing demand exists for novel therapeutic strategies against biofilm infections, which are a grave health wise on mucosal surfaces and medical devices. From fungi, a large number of secondary metabolites with antimicrobial activity have been characterized. This review discusses natural compounds from fungi which are effective against fungal and bacterial biofilms. Some molecules are able to block the cell communication process essential for biofilm formation (known as quorum sensing), others can penetrate and kill cells within the structure. Several targets have been identified, ranging from the inhibition of quorum sensing receptors and virulence factors, to cell wall synthesizing enzymes. Only one group of these fungal metabolites has been optimized and made it to the market, but more preclinical studies are ongoing to expand the biofilm-fighting arsenal. The broad diversity of bioactive compounds from fungi, their activities against various pathogens, and the multi-target trait of some molecules are promising aspects of fungal secondary metabolites. Future screenings for biofilm-controlling compounds will contribute to several novel clinical applications. 
Estrela, A.B.; Abraham, W.-R. Fungal Metabolites for the Control of Biofilm Infections. Agriculture 2016, 6, 37.

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sexta-feira, 12 de agosto de 2016

Flavones: From Biosynthesis to Health Benefits

Flavones correspond to a flavonoid subgroup that is widely distributed in the plants, and which can be synthesized by different pathways, depending on whether they contain C- or O-glycosylation and hydroxylated B-ring. Flavones are emerging as very important specialized metabolites involved in plant signaling and defense, as well as key ingredients of the human diet, with significant health benefits. Here, we appraise flavone formation in plants, emphasizing the emerging theme that biosynthesis pathway determines flavone chemistry. Additionally, we briefly review the biological activities of flavones, both from the perspective of the functions that they play in biotic and abiotic plant interactions, as well as their roles as nutraceutical components of the human and animal diet.
Jiang, N.; Doseff, A.I.; Grotewold, E. Flavones: From Biosynthesis to Health Benefits. Plants 2016, 5, 27.

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New Perspectives on the Use of Phytochemicals as an Emergent Strategy to Control Bacterial Infections Including Biofilms

The majority of current infectious diseases are almost untreatable by conventional antibiotic therapy given the advent of multidrug-resistant bacteria. The degree of severity and the persistence of infections are worsened when microorganisms form biofilms. Therefore, efforts are being applied to develop new drugs not as vulnerable as the current ones to bacterial resistance mechanisms, and also able to target bacteria in biofilms. Natural products, especially those obtained from plants, have proven to be outstanding compounds with unique properties, making them perfect candidates for these much-needed therapeutics. This review presents the current knowledge on the potentialities of plant products as antibiotic adjuvants to restore the therapeutic activity of drugs. Further, the difficulties associated with the use of the existing antibiotics in the treatment of biofilm-related infections are described. To counteract the biofilm resistance problems, innovative strategies are suggested based on literature data. Among the proposed strategies, the use of phytochemicals to inhibit or eradicate biofilms is highlighted. An overview on the use of phytochemicals to interfere with bacterial quorum sensing (QS) signaling pathways and underlying phenotypes is provided. The use of phytochemicals as chelating agents and efflux pump inhibitors is also reviewed.
Borges, A.; Abreu, A.C.; Dias, C.; Saavedra, M.J.; Borges, F.; Simões, M. New Perspectives on the Use of Phytochemicals as an Emergent Strategy to Control Bacterial Infections Including Biofilms. Molecules 2016, 21, 877.

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Yacon (Smallanthus sonchifolius) as a Food Supplement: Health-Promoting Benefits of Fructooligosaccharides

Yacon (Smallanthus sonchifolius), a perennial plant of the family Asteraceae native to the Andean regions of South America, is an abundant source of fructooligosaccharides (FOS). This comprehensive review of the literature addressed the role of yacon supplementation in promoting health and reducing the risk of chronic diseases. According to several preclinical and clinical trials, FOS intake favors the growth of health-promoting bacteria while reducing pathogenic bacteria populations. Moreover, the endproducts of FOS fermentation by the intestinal microbiota, short chain fatty acids (SCFA), act as substrates or signaling molecules in the regulation of the immune response, glucose homeostasis and lipid metabolism. As a result, glycemic levels, body weight and colon cancer risk can be reduced. Based on these findings, most studies reviewed concluded that due to their functional properties, yacon roots may be effectively used as a dietary supplement to prevent and treat chronic diseases.
Caetano, B.F.R.; de Moura, N.A.; Almeida, A.P.S.; Dias, M.C.; Sivieri, K.; Barbisan, L.F. Yacon (Smallanthus sonchifolius) as a Food Supplement: Health-Promoting Benefits of Fructooligosaccharides. Nutrients 2016, 8, 436.

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Capsaicin: From Plants to a Cancer-Suppressing Agent

Capsaicinoids are plant secondary metabolites, capsaicin being the principal responsible for the pungency of chili peppers. It is biosynthesized through two pathways involved in phenylpropanoid and fatty acid metabolism. Plant capsaicin concentration is mainly affected by genetic, environmental and crop management factors. However, its synthesis can be enhanced by the use of elicitors. Capsaicin is employed as food additive and in pharmaceutical applications. Additionally, it has been found that capsaicin can act as a cancer preventive agent and shows wide applications against various types of cancer. This review is an approach in contextualizing the use of controlled stress on the plant to increase the content of capsaicin, highlighting its synthesis and its potential use as anticancer agent.
Chapa-Oliver, A.M.; Mejía-Teniente, L. Capsaicin: From Plants to a Cancer-Suppressing Agent. Molecules 2016, 21, 931.

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Biopesticides for Locust Control

Effects of Secondary Plant Metabolites on Microbial Populations: Changes in Community Structure and Metabolic Activity in Contaminated Environments

Secondary plant metabolites (SPMEs) play an important role in plant survival in the environment and serve to establish ecological relationships between plants and other organisms. Communication between plants and microorganisms via SPMEs contained in root exudates or derived from litter decomposition is an example of this phenomenon. In this review, the general aspects of rhizodeposition together with the significance of terpenes and phenolic compounds are discussed in detail. We focus specifically on the effect of SPMEs on microbial community structure and metabolic activity in environments contaminated by polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs). Furthermore, a section is devoted to a complex effect of plants and/or their metabolites contained in litter on bioremediation of contaminated sites. New insights are introduced from a study evaluating the effects of SPMEs derived during decomposition of grapefruit peel, lemon peel, and pears on bacterial communities and their ability to degrade PCBs in a long-term contaminated soil. The presented review supports the “secondary compound hypothesis” and demonstrates the potential of SPMEs for increasing the effectiveness of bioremediation processes.
Musilova, L.; Ridl, J.; Polivkova, M.; Macek, T.; Uhlik, O. Effects of Secondary Plant Metabolites on Microbial Populations: Changes in Community Structure and Metabolic Activity in Contaminated Environments. Int. J. Mol. Sci. 2016, 17, 1205.

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Phenolic and Volatile Composition of a Dry Spearmint (Mentha spicata L.) Extract

The present paper reports a complete mass spectrometric characterization of both the phenolic and volatile fractions of a dried spearmint extract. Phenolic compounds were analysed by ultra-high performance liquid chromatography-electrospray ionization-mass spectrometry (UHPLC-ESI-MSn) and a total of 66 compounds were tentatively identified, being the widest phenolic characterisation of spearmint to date. The analysis suggests that the extract is composed of rosmarinic acid and its derivatives (230.5 ± 13.5 mg/g) with smaller amounts of salvianolic acids, caffeoylquinic acids, hydroxybenzoic acids, hydroxycinnamic acids, flavones, and flavanones. Head space solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) technique, that was applied to characterize the volatile fraction of spearmint, identified molecules belonging to different chemical classes, such as p-cymene, isopiperitone, and piperitone, dihydroedulan II, menthone, p-cymen-8-ol, and β-linalool. This comprehensive phytochemical analysis can be useful to test the authenticity of this product rich in rosmarinic acid and other phenolics, and when assessing its biological properties. It may also be applied to other plant-derived food extracts and beverages containing a broad range of phytochemical compounds.
Cirlini, M.; Mena, P.; Tassotti, M.; Herrlinger, K.A.; Nieman, K.M.; Dall’Asta, C.; Del Rio, D. Phenolic and Volatile Composition of a Dry Spearmint (Mentha spicata L.) Extract. Molecules 2016, 21, 1007.

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Physiological Effects of Nature Therapy: A Review of the Research in Japan

Humans have evolved into what they are today after the passage of 6–7 million years. If we define the beginning of urbanization as the rise of the industrial revolution, less than 0.01% of our species’ history has been spent in modern surroundings. Humans have spent over 99.99% of their time living in the natural environment. The gap between the natural setting, for which our physiological functions are adapted, and the highly urbanized and artificial setting that we inhabit is a contributing cause of the “stress state” in modern people. In recent years, scientific evidence supporting the physiological effects of relaxation caused by natural stimuli has accumulated. This review aimed to objectively demonstrate the physiological effects of nature therapy. We have reviewed research in Japan related to the following: (1) the physiological effects of nature therapy, including those of forests, urban green space, plants, and wooden material and (2) the analyses of individual differences that arise therein. The search was conducted in the PubMed database using various keywords. We applied our inclusion/exclusion criteria and reviewed 52 articles. Scientific data assessing physiological indicators, such as brain activity, autonomic nervous activity, endocrine activity, and immune activity, are accumulating from field and laboratory experiments. We believe that nature therapy will play an increasingly important role in preventive medicine in the future.
Song, C.; Ikei, H.; Miyazaki, Y. Physiological Effects of Nature Therapy: A Review of the Research in Japan. Int. J. Environ. Res. Public Health 2016, 13, 781.

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Integrating Insect Life History and Food Plant Phenology: Flexible Maternal Choice Is Adaptive

Experience of insect herbivores and their natural enemies in the natal habitat is considered to affect their likelihood of accepting a similar habitat or plant/host during dispersal. Growing phenology of food plants and the number of generations in the insects further determines lability of insect behavioural responses at eclosion. We studied the effect of rearing history on oviposition preference in a multivoltine herbivore (Pieris brassicae), and foraging behaviour in the endoparasitoid wasp (Cotesia glomerata) a specialist enemy of P. brassicae. Different generations of the insects are obligatorily associated with different plants in the Brassicaceae, e.g., Brassica rapa, Brassica nigra and Sinapis arvensis, exhibiting different seasonal phenologies in The Netherlands. Food plant preference of adults was examined when the insects had been reared on each of the three plant species for one generation. Rearing history only marginally affected oviposition preference of P. brassicae butterflies, but they never preferred the plant on which they had been reared. C. glomerata had a clear preference for host-infested B. rapa plants, irrespective of rearing history. Higher levels of the glucosinolate breakdown product 3-butenyl isothiocyanate in the headspace of B. rapa plants could explain enhanced attractiveness. Our results reveal the potential importance of flexible plant choice for female multivoltine insects in nature.
Fei, M.; Harvey, J.A.; Weldegergis, B.T.; Huang, T.; Reijngoudt, K.; Vet, L.M.; Gols, R. Integrating Insect Life History and Food Plant Phenology: Flexible Maternal Choice Is Adaptive. Int. J. Mol. Sci. 2016, 17, 1263.

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Cytotoxic and Antimicrobial Constituents from the Essential Oil of Lippia alba (Verbenaceae)

Backgroud: Lippia alba (Verbenaceae) is a plant widely used in folk medicine to treat various diseases. The present work deals with the chemical composition of the crude essential oil extracted from leaves of L. alba and evaluation of its antimicrobial and cytotoxic activities. Methods: Leaves of L. alba were extracted by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) as well as by nuclear magnetic resonance (NMR) spectroscopy. Cytotoxic and antimicrobial activities of crude essential oil were evaluated in vitro using MTT and broth microdilution assays, respectively. Results: Chemical analysis afforded the identification of 39 substances corresponding to 99.45% of the total oil composition. Concerning the main compounds, monoterpenes nerol/geraniol and citral correspond to approximately 50% of crude oil. The cytotoxic activity of obtained essential oil against several tumor cell lines showed IC50 values ranging from 45 to 64 µg/mL for B16F10Nex2 (murine melanoma) and A549 (human lung adenocarcinoma). In the antimicrobial assay, was observed that all tested yeast strains, except C. albicans, were sensitive to crude essential oil. MIC values were two to four-folds lower than those determined to bacterial strains. Conclusion: Analysis of chemical composition of essential oils from leaves of L. alba suggested a new chemotype nerol/geraniol and citral. Based in biological evidences, a possible application for studied oil as an antifungal in medicine, as well as in agriculture, is described.
Santos, N.O.; Pascon, R.C.; Vallim, M.A.; Figueiredo, C.R.; Soares, M.G.; Lago, J.H.G.; Sartorelli, P. Cytotoxic and Antimicrobial Constituents from the Essential Oil of Lippia alba (Verbenaceae). Medicines 2016, 3, 22.

Link:

Hıstory Of The Aztecs Documentary

Hippocrates Biography

What Hippocrates Knew and We Have Forgotten

Why is Nutrition so Commercialized?

Why is Nutrition so Commercialized?

Agavins Increase Neurotrophic Factors and Decrease Oxidative Stress in the Brains of High-Fat Diet-Induced Obese Mice

Background: Fructans obtained from agave, called agavins, have recently shown significant benefits for human health including obesity. Therefore, we evaluated the potential of agavins as neuroprotectors and antioxidants by determining their effect on brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF) as well as oxidative brain damage in of obese mice. Methods: Male C57BL/6J mice were fed a high-fat diet (HFD) and treated daily with 5% (HFD/A5) or 10% (HFD/A10) of agavins or a standard diet (SD) for 10 weeks. The levels of BDNF and GDNF were evaluated by ELISA. The oxidative stress was evaluated by lipid peroxidation (TBARS) and carbonyls. SCFAs were also measured with GC-FID. Differences between groups were assessed using ANOVA and by Tukey’s test considering p < 0.05. Results: The body weight gain and food intake of mice HFD/A10 group were significantly lower than those in the HFD group. Agavins restored BDNF levels in HFD/A5 group and GDNF levels of HFD/A5 and HFD/A10 groups in cerebellum. Interestingly, agavins decreased TBARS levels in HFD/A5 and HFD/A10 groups in the hippocampus, frontal cortex and cerebellum. Carbonyl levels were also lower in HFD/A5 and HFD/A10 for only the hippocampus and cerebellum. It was also found that agavins enhanced SCFAs production in feces. Conclusion: Agavins may act as bioactive ingredients with antioxidant and protective roles in the brain.

Franco-Robles, E.; López, M.G. Agavins Increase Neurotrophic Factors and Decrease Oxidative Stress in the Brains of High-Fat Diet-Induced Obese Mice. Molecules 2016, 21, 998.

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Capsaicin Synthesis Requires in Situ Phenylalanine and Valine Formation in in Vitro Maintained Placentas from Capsicum chinense


Capsaicinoids (CAP) are nitrogenous metabolites formed from valine (Val) and phenylalanine (Phe) in the placentas of hot Capsicum genotypes. Placentas of Habanero peppers can incorporate inorganic nitrogen into amino acids and have the ability to secure the availability of the required amino acids for CAP biosynthesis. In order to determine the participation of the placental tissue as a supplier of these amino acids, the effects of blocking the synthesis of Val and Phe by using specific enzyme inhibitors were analyzed. Isolated placentas maintained in vitro were used to rule out external sources′ participation. Blocking Phe synthesis, through the inhibition of arogenate dehydratase, significantly decreased CAP accumulation suggesting that at least part of Phe required in this process has to be produced in situ. Chlorsulfuron inhibition of acetolactate synthase, involved in Val synthesis, decreased not only Val accumulation but also that of CAP, pointing out that the requirement for this amino acid can also be fulfilled by this tissue. The presented data demonstrates that CAP accumulation in in vitro maintained placentas can be accomplished through the in situ availability of Val and Phe and suggests that the synthesis of the fatty acid chain moiety may be a limiting factor in the biosynthesis of these alkaloids.

Baas-Espinola, F.M.; Castro-Concha, L.A.; Vázquez-Flota, F.A.; Miranda-Ham, M.L. Capsaicin Synthesis Requires in Situ Phenylalanine and Valine Formation in in Vitro Maintained Placentas from Capsicum chinense. Molecules 2016, 21, 799.

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Agrimonia eupatoria L. and Cynara cardunculus L. Water Infusions: Comparison of Anti-Diabetic Activities

Diabetes mellitus (DM) is frequently diagnosed at a time when patients already suffer from several cardiovascular complications. Our previously published data (Molecules 201520 (11): 20538-50) on the anti-oxidative properties of Agrimonia eupatoria L. (AE) and Cynara cardunculus L. (CC) prompted us to extend the available evidence on their possible protective activities on selected DM-related parameters in a streptozotocin-induced DM rat model and in a series of in vitro experiments. Male rats were divided into four groups: control group, untreated diabetic group, AE and CC treated diabetic groups. During a five-week period, changes in blood glucose and body weight were monitored. Then, rats were sacrificed and subjected to the assessment of changes in the reactivity of aortas and measurement of butyrylcholinesterase activity. To complete the panel of experiments, α-glucosidase activity was assessed in vitro. Our results demonstrate that both tested extracts exert similar anti-diabetic activities. However, better anti-oxidant activity of the A. eupatoria extract indicates its higher clinical potential in the prevention and/or adjuvant therapy of developing cardiovascular complications related to DM and diseases associated with oxidative stress.

Kuczmannová, A.; Balažová, A.; Račanská, E.; Kameníková, M.; Fialová, S.; Majerník, J.; Nagy, M.; Gál, P.; Mučaji, P. Agrimonia eupatoria L. and Cynara cardunculus L. Water Infusions: Comparison of Anti-Diabetic Activities. Molecules 2016, 21, 564.
Agrimonia eupatoria

Antioxidant and Anti-Fatigue Constituents of Okra

Okra (Abelmoschus esculentus (L.) Moench), a healthy vegetable, is widely spread in tropical and subtropical areas. Previous studies have proven that okra pods possess anti-fatigue activity, and the aim of this research is to clarify the anti-fatigue constituents. To achieve this, we divided okra pods (OPD) into seeds (OSD) and skins (OSK), and compared the contents of total polysaccharides, total polyphenols, total flavonoids, isoquercitrin, and quercetin-3-O-gentiobiose and the antioxidant activity in vitroand anti-fatigue activity in vivo between OSD and OSK. The contents of total polyphenols and total polysaccharides were 29.5% and 14.8% in OSD and 1.25% and 43.1% in OSK, respectively. Total flavonoids, isoquercitrin and quercetin-3-O-gentiobiose (5.35%, 2.067% and 2.741%, respectively) were only detected in OSD. Antioxidant assays, including 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, ferric reducing antioxidant power (FRAP) and reducing power test, and weight-loaded swimming test showed OSD possessed significant antioxidant and anti-fatigue effects. Moreover, biochemical determination revealed that that anti-fatigue activity of OSD is caused by reducing the levels of blood lactic acid (BLA) and urea nitrogen (BUN), enhancing hepatic glycogen storage and promoting antioxidant ability by lowering malondialdehyde (MDA) level and increasing superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) levels. These results proved okra seeds were the anti-fatigue part of okra pods and polyphenols and flavonoids were active constituents.
Xia, F.; Zhong, Y.; Li, M.; Chang, Q.; Liao, Y.; Liu, X.; Pan, R. Antioxidant and Anti-Fatigue Constituents of Okra. Nutrients 2015, 7, 8846-8858.

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Biodiversidad 89 / 2016-3

En el mundo crece la violencia. El asesinato y las desapariciones se vuelven un signo ominoso de los días. La represión se hace abierta, a veces dirigida y a veces confusa, genérica, masiva, siempre a mansalva. Los acuerdos de libre comercio, el sistema agroalimentario industrial, los derechos de propiedad intelectual sobre las semillas y la vida misma, el acaparamiento de tierras, el sometimiento de las mujeres a designios patriarcales e injustos, las devastaciones que se suman, amenazan el futuro común que nos merecemos. Pero la gente sigue buscando cuidar, entender, compartir, procurar, abrazar, impulsar, procrear, alimentar, imaginar, entender junta, responsabilizarse e implicarse, reproducir y cuidar la vida en toda la extensión de la palabra. Para eso está la Biodiversidad, con su información y su razonamiento compartido.

In Vitro Reversible and Time-Dependent CYP450 Inhibition Profiles of Medicinal Herbal Plant Extracts Newbouldia laevis and Cassia abbreviata: Implications for Herb-Drug Interactions

This study evaluated the effects of Newbouldia laevis and Cassia abbreviata extracts on CYP450 enzyme activity. Recombinant CYP450 enzyme and fluorogenic substrates were used for evaluating inhibition, allowing the assessment of herb–drug interactions (HDI). Phytochemical fingerprinting was performed using UPLC-MS. The herbal extracts were risk ranked for HDI based on the IC50 values determined for each CYP enzyme. Newbouldia laevis inhibited CYP1A2, CYP2C9, and CYP2C19 enzyme activities with Kiof 2.84 µg/mL, 1.55 µg/mL, and 1.23 µg/mL, respectively. N. laevis exhibited a TDI (4.17) effect on CYP1A2 but not CYP2C9 and CYP2C19 enzyme activities. Cassia abbreviata inhibited CYP1A2, CYP2C9, and CYP2C19 enzyme activities showing a Ki of 4.86 µg/mL, 5.98 µg/mL, and 1.58 µg/mL, respectively. TDI potency assessment for Cassia abbreviata showed it as a potential TDI candidate (1.64) for CYP1A2 and CYP2C19 (1.72). UPLC-MS analysis showed that Newbouldia laevis and Cassia abbreviata possess polyphenols that likely give them their therapeutic properties; some of them are likely to be responsible for the observed inhibition. The observations made in this study suggest the potential for these herbal compounds to interact, especially when co-administered with other medications metabolized by these CYP450 enzymes.
Thomford, N.E.; Dzobo, K.; Chopera, D.; Wonkam, A.; Maroyi, A.; Blackhurst, D.; Dandara, C. In Vitro Reversible and Time-Dependent CYP450 Inhibition Profiles of Medicinal Herbal Plant Extracts Newbouldia laevis and Cassia abbreviata: Implications for Herb-Drug Interactions. Molecules 2016, 21, 891.

Link:

Enciclopedia de Nutracéuticos

Etnobotánica y fitoterapia en América

Plantas medicinales para enfermedades reumáticas

Pindamonhangaba, São Paulo: V Workshop Políticas Públicas de Plantas Medicinais, Aromáticas


Botanica indigena de chile

Medicina tradicional en los corregimientos de medellin

Chemical Elicitor-Induced Modulation of Antioxidant Metabolism and Enhancement of Secondary Metabolite Accumulation in Cell Suspension Cultures of Scrophularia kakudensis Franch

Figure 1. Induction of friable callus after two weeks (A) and four weeks (B); friable callus cultured in liquid medium with cells deposited on the walls of the flask (C); cell suspension cultures derived from callus cultures (D).

Abstract

Scrophularia kakudensis is an important medicinal plant with pharmaceutically valuable secondary metabolites. To develop a sustainable source of naturaceuticals with vital therapeutic importance, a cell suspension culture was established in S. kakudensisfor the first time. Friable calli were induced from the leaf explants cultured on a Murashige and Skoog (MS) medium containing 3.0 mg·L−1 6-benzyladenine (BA) in a combination with 2 mg·L−1 2,4-dichlorophenoxy acetic acid (2,4-D). From the callus cultures, a cell suspension culture was initiated and the cellular differentiation was investigated. In addition, the effect of biotic elicitors such as methyl jasmonate (MeJa), salicylic acid (SA), and sodium nitroprusside (SNP) on the accumulation of secondary metabolites and antioxidant properties was demonstrated. Among the elicitors, the MeJa elicited the accumulation of total phenols, flavonoids, and acacetin, a flavonoid compound with multiple pharmaceutical values. Similarly, the higher concentrations of the MeJa significantly modulated the activities of antioxidant enzymes and enhanced the scavenging potentials of free radicals of cell suspension extracts. Overall, the outcomes of this study can be utilized for the large scale production of pharmaceutically important secondary metabolites from S. kakudensis through cell suspension cultures.

Manivannan, A.; Soundararajan, P.; Park, Y.G.; Jeong, B.R. Chemical Elicitor-Induced Modulation of Antioxidant Metabolism and Enhancement of Secondary Metabolite Accumulation in Cell Suspension Cultures of Scrophularia kakudensis Franch. Int. J. Mol. Sci. 2016, 17, 399.

Link:

TV Costa Norte - Especialista em plantas medicinais explica o benefício ...

quinta-feira, 11 de agosto de 2016

Stachytarpheta jamaicensis (L.) Vahl (Verbenaceae) - plantas catalogadas por A. de Saint-Hilaire


A. de Saint-Hilaire

Auguste de Saint-Hilaire nasceu na França em 1779. Desde cedo se interessou por ciências naturais, tornando-se um grande botânico. Em 1816, ele veio para o Brasil a convite da coroa portuguesa e percorreu milhares de quilômetros estudando a flora nativa, inclusive as plantas medicinais. Ele viajou por quase toda Minas Gerais, além dos Estados de Goiás, Espírito Santo, Rio de Janeiro, São Paulo, Paraná, Santa Catarina, Rio Grande do Sul e a Província Cisplatina (hoje o Uruguai). Em suas viagens, que duraram 6 anos, Saint-Hilaire coletou 7 mil exemplares de plantas, sendo 4.500 delas desconhecidas na época. Este acervo está hoje no Museu de História Natural de Paris. Saint-Hilaire publicou vários livros sobre o Brasil, entre eles a obra Plantas Usuais dos Brasileiros, traduzida para o português pelo CEPLAMT em 2009.

Em 2016 comemora-se os 200 anos da chegada do naturalista Auguste de Saint Hilaire ao Brasil e alguns eventos ocorrerão durante o ano para celebrar o acontecimento.

Simpósio de Plantas Medicinais vai comemorar os 200 anos de Auguste de Saint-Hilaire no Brasil

Evento marca os 200 anos da chegada de Auguste de Saint-Hilaire ao Brasil, e acontecerá de 21 a 24 de setembro, em Belo Horizonte
No evento serão comemorados os 200 anos da chegada ao Brasil do naturalista francês Auguste de Saint-Hilaire. - Reprodução internet.

De 21 a 24 de setembro de 2016 acontecerá em Belo Horizonte – Minas Gerais, o 24º Simpósio de Plantas Medicinais do Brasil. O principal objetivo do evento é conscientizar sobre a necessidade urgente de aproveitamento adequado e conservação das plantas medicinais brasileiras, especialmente as Ameríndias. Além disso, haverá na ocasião comemoração aos 200 anos da chegada ao Brasil do , cujo nome foi dado ao Parque Nacional de Saint-Hilaire/Lange como homenagem à sua contribuição para a botânica brasileira.

O Simpósio de Plantas Medicinais do Brasil é um evento renomado no país que reúne, a cada dois anos, cientistas, estudantes e profissionais da área de plantas medicinais, etnobotânica, farmacologia, fitoquímica, fitoterápicos, cosméticos, dentre outras.

Esta edição do Simpósio está sendo organizada pelo Centro Especializado em Plantas Aromáticas, Medicinais e Tóxicas (CEPLAMT), pelo Departamento de Química e pela Faculdade de Farmácia da UFMG, com a colaboração de pesquisadores de outras Instituições Mineiras (UFV, UFVJM, UFOP, UFSJ, UFU e UFJF). Convidados de diferentes Instituições, nacionais e estrangeiras, apresentarão/ discutirão aspectos relacionados à história natural, saúde pública, etnobotânica, etnofarmacologia, fitoquímica, biotecnologia, cultivo e melhoramento, controle de qualidade, desenvolvimento tecnológico, entre outras áreas de investigação, em conferências e mesas redondas. Haverá também minicursos, lançamento de livros e de selo comemorativo.

Para conhecer a programação, inscrever-se e consultar outras informações, acesse aqui.

Link:
https://www.abrasco.org.br/site/2016/08/simposio-de-plantas-medicinais-vai-comemorar-os-200-anos-de-auguste-de-saint-hilaire-no-brasil/

Maternal Diet May Affect Stress Responses in Children

How to Avoid the Obesity-Related Plastic Chemical BPA

terça-feira, 9 de agosto de 2016

Extra virgin olive oil is the best option for frying fish

Date: July 15, 2016

Source: University of the Basque Country

Summary:
Researchers have studied the changes that take place in fish lipids and in the oil during frying processes, and have concluded that using extra virgin olive oil is the best choice.

Researchers at the UPV/EHU-University of the Basque Country have studied the changes that take place in fish lipids and in the oil during frying processes

The frying techniques, the nature of the oil used and the fish species have been shown to exert a great influence on the changes that take place during the process. UPV/EHU researchers have shown that the choice of cooking oil is hugely important owing to its impact on the lipid profile in the fish and on the possible generation of toxic compounds in the oil during frying, which can influence food safety and human health.

The journal Food Research International has published the article 'The influence of frying technique, cooking oil and fish species on the changes occurring in fish lipids and oil during shallow-frying, studied by H-1 NMR', which deals with the work carried out by Bárbara Nieva-Echevarría, Encarnación Goicoechea, María José Manzanos and María Dolores Guillén. To conduct this research, fillets of European seabass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata) were shallow-fried in a frying plan and in a microwave oven using extra virgin olive oil and refined sunflower oil. The changes that took place in the lipid composition of the fish and of the frying oil were studied by means of Proton Nuclear Magnetic Resonance Imaging (H-1 NMR).

Migration of lipid components between the fish and the frying oil

During the shallow-frying of the fish under domestic conditions, not only do the fish lipids migrate to the frying oil, the components of the oil are also transferred to the fillet of fish. As a result, the composition of the oil used for frying is modified: firstly, it is enriched by the acyl groups ('fatty acids') that are present in a higher concentration in the fish fat than in the original oil, and secondly, and simultaneously, it is depleted in the acyl groups present in a higher concentration in the original oil than in the fish fat. So after having been used for frying, the extra virgin olive oil was richer in omega-3, omega-1 acyl groups, linoleic and saturated fats (from the fish) and poorer in oleic, which is the main acyl group in olive oil. Likewise, after having been used for frying, the sunflower oil was richer in all the acyl group types (coming from the fish) except linoleic, which is the majority acyl group in sunflower oil. Furthermore, after frying, both types of oil were enriched by small amounts of cholesterol (from the fish).

As regards the fat in the fish fillets, its composition also changed during the frying process, and became enriched by the acyl groups present in a higher concentration in the frying oil than in the fillet (in other words, oleic if extra virgin olive oil was used, or linoleic if sunflower oil was used) and in plant sterols. Simultaneously, during the frying process the lipids in the fish fillets were depleted in the acyl groups and minority components present in a greater concentration in the raw fillet than in the original oils, such as, for example, the omega-3 docosahexaenoic (DHA) and eicosapentaenoic (EPA) polyunsaturated groups.

Thermal oxidation reaction

Besides the migration of lipids during frying, because these oils are subjected to high temperatures (170 ºC) in the presence of oxygen, certain small-scale thermal oxidation may take place in them. In the extra virgin olive oil used for frying fish, this thermal oxidation reaction did not occur as it is more degradation-resistant than sunflower oil. Yet in the sunflower oil used for frying fish in the frying pan, secondary oxidation compounds (aldehydes) were formed; some of them are regarded as potentially toxic depending on the concentration in which they are found. It should be pointed out that these compounds did not form in the sunflower oil used to fry the fish in the microwave oven. Therefore, in view of the results obtained and bearing in mind the generation of these compounds that are potentially harmful for health, the healthiest option for frying is to use extra virgin olive and fry in the microwave.

Fat content of the fried fish

The fish species used was also seen to be a factor that considerably influences the fat absorption-desorption process during frying. The fat content of the gilthead seabream had diminished after frying while that of the European seabass remained similar or increased with respect to the starting level.

This study shows that the frying technique, the type of oil used and the fish species exert a great influence on the changes that take place during the frying process. Correctly selecting the oil is of paramount importance owing to its impact on the final composition of the fat in the cooked fillet and the possible generation of potentially toxic compounds in the oil during the frying process, which will greatly influence food safety and human health.

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The above post is reprinted from materials provided by University of the Basque Country. Note: Content may be edited for style and length.

Journal Reference:
Bárbara Nieva-Echevarría, Encarnación Goicoechea, María J. Manzanos, María D. Guillén. The influence of frying technique, cooking oil and fish species on the changes occurring in fish lipids and oil during shallow-frying, studied by 1H NMR. Food Research International, 2016; 84: 150 DOI: 10.1016/j.foodres.2016.03.033

Cite This Page:
University of the Basque Country. "Extra virgin olive oil is the best option for frying fish." ScienceDaily. ScienceDaily, 15 July 2016. <www.sciencedaily.com/releases/2016/07/160715114736.htm>.

Juicy news about cranberries: Blocking bacterial infections

Date: July 19, 2016

Source: Worcester Polytechnic Institute

Summary:
Illuminating traditional wisdom with chemistry and biophysics, a research team has characterized the role of compounds in cranberry juice that block the critical first step in bacterial infections, the ability of bacteria to adhere to surfaces and form biofilms. The results open a potential new area of focus for antibiotic drug development, particularly drugs to respond to the emergence of antibiotic-resistant superbugs.

Illuminating traditional wisdom with chemistry and biophysics, a research team at Worcester Polytechnic Institute (WPI) and the University of Massachusetts Dartmouth has characterized the role of compounds in cranberry juice that block the critical first step in bacterial infections. The results open a potential new area of focus for antibiotic drug development.

The research team, led by Terri Camesano, PhD, professor of chemical engineering and dean of graduate studies at WPI, and Catherine Neto, PhD, professor and chair of chemistry and biochemistry at UMass Dartmouth, report their findings in the paper "Atomic force microscopy-guided fractionation reveals the influence of cranberry phytochemicals on adhesion of Escherichia coli" published in The Royal Society of Chemistry journalFood & Function.

"With the emergence of new superbugs that are resistant to current antibiotics, our hope is to better understand the mechanisms of bacterial infection so we can identify potential new antibiotic drug targets," Camesano said.

According to the U.S. Centers for Disease Control and Prevention (CDC) at least 2 million Americans are infected each year with drug-resistant bacteria, while some 23,000 die from those infections. To cause an infection, bacteria must first adhere to a host and accumulate in sufficient numbers to form a biofilm. In the new paper, the team reports that compounds in cranberry juice called flavonols greatly reduced the ability of the bacteria E. coli to stick to a surface (various strains of E. coli are responsible for many types of infections, including those of the urinary tract.)

Previous work by Camesano, Neto, and others has shown that a group of compounds called proanthocyanidins (PACs) likely play a role in cranberry juice's ability to block bacterial adhesion. In the new study, Neto's team used advanced chemical techniques to separate or "fractionate" cranberry juice into its constituent chemical compounds and characterize them. Then at WPI, Camesano's team cultured E. coli cells in samples of the fractionated juice and used an atomic force microscope to measure the bacteria's ability to bond to a surface. "This study is the first to combine an assay-guided fractionation approach with atomic force microscopy to identify cranberry juice constituents that most strongly influence E. coli adhesion forces," the authors wrote.

After the first round of testing, samples that showed the greatest ability to reduce E. coli adhesion were further fractionated at UMass Dartmouth and then returned to WPI for testing. The process went on in similar cycles, further reducing the number of compounds in each sample, to home in on the key chemicals affecting adhesion. Those tests found that flavonols significantly reduced E. coli adhesion, both on their own, and in the presence of PACs. One particular group called flavonol galactosides showed the strongest results. "Like the PACs, we think the flavonols are part of the plant's defense system," Neto said. "They are secondary metabolites that are produced in greater concentrations when the plant is under stress or in the presence of pathogens."

"This is an excellent collaboration that pairs what we do on the biophysical side at WPI with the work that UMass Dartmouth does on the biochemical side," Camesano said. Added Neto, "I think we have a great partnership with WPI because we come at the question from different angles and together we provide a nice picture of what's going on."

The new data builds on previously published work, in which Camesano and her team showed that cranberry juice compresses the tiny tendrils (known as fimbriae) on the surface of the E. coli bacteria that enable it to bind tightly to the lining of the urinary tract. The change in shape greatly reduces the ability of the bacteria to stay put long enough to initiate an infection. Flavonols also are likely to affect the ability of fimbriae to bind to surfaces, but in a different way than PACs do, Camesano noted.

"This strongly suggests the anti-adhesive role of other classes of cranberry compounds in conjunction with already known PACs and may have implications for development of alternative antibacterial treatments," the authors wrote. "These compounds should be further explored, both individually and in combination for their antimicrobial properties against various bacterial diseases [to] give us a therapeutic edge against these 'superbugs.'"

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The above post is reprinted from materials provided by Worcester Polytechnic Institute. Note: Content may be edited for style and length.

Journal Reference:
Prachi Gupta, Biqin Song, Catherine Neto, Terri A. Camesano. Atomic force microscopy-guided fractionation reveals the influence of cranberry phytochemicals on adhesion of Escherichia coli. Food Funct., 2016; 7 (6): 2655 DOI: 10.1039/C6FO00109B

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Worcester Polytechnic Institute. "Juicy news about cranberries: Blocking bacterial infections." ScienceDaily. ScienceDaily, 19 July 2016. <www.sciencedaily.com/releases/2016/07/160719152220.htm>.