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1

Cerebral Accumulation of Dietary Derivable Plant Sterols does not Interfere with Memory and Anxiety Related Behavior in Abcg5?\\/? Mice  

Microsoft Academic Search

Plant sterols such as sitosterol and campesterol are frequently applied as functional food in the prevention of atherosclerosis.\\u000a Recently, it became clear that plasma derived plant sterols accumulate in murine brains. We questioned whether plant sterols\\u000a in the brain are associated with alterations in brain cholesterol homeostasis and subsequently with brain functions. ATP binding\\u000a cassette (Abc)g5?\\/? mice, a phytosterolemia model,

Tim Vanmierlo; Kris Rutten; Leonie C. van Vark-van der Zee; Silvia Friedrichs; Vincent W. Bloks; Arjan Blokland; Frans C. Ramaekers; Eric Sijbrands; Harry Steinbusch; Jos Prickaerts; Folkert Kuipers; Dieter Lütjohann; Monique Mulder

2

Metabolism of plant sterols by nematodes  

Microsoft Academic Search

Parasitic nematodes do not biosynthesize sterolsde novo and therefore possess a nutritional requirement for sterol, which must be obtained from their hosts. Consequently, the metabolism\\u000a of phytosterols by plant-parasitic nematodes is an important process with potential for selective exploitation. The sterol\\u000a compositions of several species of plant-parasitic nematodes were determined by capillary gas chromatography-mass spectrometry\\u000a and compared with the sterol

David J. Chitwood; William R. Lusby

1991-01-01

3

Molecular Genetics of Plant Sterol Backbone Synthesis  

Microsoft Academic Search

Sterols, which are biosynthesized via the cytoplasmic mevalonate (MVA) pathway, are important structural components of the\\u000a plasma membrane and precursors of steroid hormones in both vertebrates and plants. Ergosterol and cholesterol are the major\\u000a sterols in yeast and vertebrates, respectively. In contrast, plants produce a wide variety of phytosterols, which have various\\u000a functions in plant development. Although the general biosynthetic

Masashi Suzuki; Toshiya Muranaka

2007-01-01

4

A Reappraisal of the Mechanism by Which Plant Sterols Promote Neutral Sterol Loss in Mice  

PubMed Central

Dietary plant sterols (PS) reduce serum total and LDL-cholesterol in hyperlipidemic animal models and in humans. This hypocholesterolemic effect is generally ascribed to inhibition of cholesterol absorption. However, whether this effect fully explains the reported strong induction of neutral sterol excretion upon plant sterol feeding is not known. Recent data demonstrate that the intestine directly mediates plasma cholesterol excretion into feces, i.e., without involvement of the hepato-biliary route. Objective Aim of this study was to determine whether stimulation of fecal neutral sterol loss during PS feeding is (partly) explained by increased intestinal cholesterol excretion and to assess the role of the cholesterol transporter Abcg5/Abcg8 herein. Methods and Results Wild-type mice were fed a control diet or diets enriched with increasing amounts of PS (1%, 2%, 4% or 8%, wt/wt) for two weeks. In addition, Abcg5-/- mice were fed either control or 8% PS diet. PS feeding resulted in a dose-dependent decrease of fractional cholesterol absorption (?2–7-fold reduction) in wild-type mice and ?80% reduction in Abcg5-/- mice. Furthermore, PS feeding led to a strong, dose-independent induction of neutral sterol excretion (3.4-fold in wild-types and 2.7-fold in Abcg5-/- mice) without changes in biliary cholesterol secretion. It was calculated that PS feeding stimulated intestinal cholesterol excretion by ?500% in wild-type mice and by ?250% in Abcg5-/-. Conclusions Our data indicate that in mice the cholesterol-lowering effects of PS are to a large extent attributable to stimulation of intestinal, non-bile derived, cholesterol excretion. The Abcg5/Abcg8 heterodimer is involved in facilitating this PS-induced flux of cholesterol. PMID:21738715

Brufau, Gemma; Kuipers, Folkert; Lin, Yuguang; Trautwein, Elke A.; Groen, Albert K.

2011-01-01

5

Effects of plant sterols derived from Aloe vera gel on human dermal fibroblasts in vitro and on skin condition in Japanese women  

PubMed Central

Background Aloe is known for its topical use for treating wounds and burns. Many previous studies reported the healing effects of Aloe vera. However, there are few clinical studies on the effect of orally administered A. vera gel on the skin. Aloe sterols are a type of plant sterols that have the capability to regulate the metabolism of glucose and lipids. In a recent study, we confirmed that ingested Aloe sterols reached the peripheral tissues through the bloodstream. However, their influence on dermal fibroblasts has not been investigated. Methods First, we investigated the capability of Aloe sterols (cycloartenol and lophenol) to stimulate human dermal fibroblasts in vitro. Then, we investigated the effect of intake of Aloe vera gel powder (AVGP) containing 40 ?g Aloe sterols on the skin conditions in Japanese women with dry skin in a randomized, double-blind, placebo-controlled trial. Results After cocultivation with Aloe sterols, the production of collagen and hyaluronic acid increased by approximately two-fold and 1.5-fold, and gene expression levels of these enzymes responsible for their synthesis were also observed in human dermal fibroblasts. An increase in arm skin hydration was observed at 8 weeks in the AVGP group, whereas a slight decrease in arm skin hydration was noted in the placebo group. However, there was no statistical difference between AVGP and placebo groups in skin moisture. In subgroup analysis, the change in the mean wrinkle depth was significantly lower in the AVGP group than in the control group. In addition, percent body fat after 8 weeks was significantly lower in the AVGP group. No AVGP intake-dependent harmful phenomenon was observed during the intake period. Conclusion The present study confirms that daily oral Aloe sterol-containing AVGP significantly reduced facial wrinkles in women aged ?40 years, and Aloe sterols stimulate collagen and hyaluronic acid production by human dermal fibroblasts.

Tanaka, Miyuki; Misawa, Eriko; Yamauchi, Koji; Abe, Fumiaki; Ishizaki, Chiaki

2015-01-01

6

Food sources of plant sterols in the EPIC Norfolk population  

Microsoft Academic Search

Objective:To investigate the intake of plant sterols and identify major dietary sources of plant sterols in the British diet.Subjects:A total of 24 798 men and women recruited during 1993–1997, participating in the European Prospective Investigation into Cancer (EPIC-Norfolk).Interventions:A database of the plant sterol (campesterol, ?-sitosterol, stigmasterol, campestanol and ?-sitostanol) content in foods, based on gas-liquid chromatography (GLC) analyses, was linked

S Klingberg; H Andersson; A Mulligan; A Bhaniani; A Welch; S Bingham; K-T Khaw; S Andersson; L Ellegĺrd

2008-01-01

7

Baseline plasma plant sterol concentrations do not predict changes in serum lipids, C-reactive protein (CRP) and plasma plant sterols following intake of a plant sterol-enriched food  

Microsoft Academic Search

Background\\/Objectives:Plant sterol (PS) consumption lowers serum cholesterol levels, while modestly increasing plasma PS concentrations. Plasma PS concentrations may reflect sterol absorption, thus individuals with high plasma plant sterol (HPS) concentrations may show greater changes in circulating cholesterol and PS than individuals with low plasma plant sterol (LPS) concentrations. The objective of this study was to examine whether HPS and LPS

A H Houweling; C A Vanstone; E A Trautwein; G S M J E Duchateau; P J H Jones; PJH Jones

2009-01-01

8

Distribution of free and glycosylated sterols within Cycas micronesica plants  

PubMed Central

Flour derived from Cycas micronesica seeds was once the dominant source of starch for Guam's residents. Cycad consumption has been linked to high incidence of human neurodegenerative diseases. We determined the distribution of the sterols stigmasterol and ?-sitosterol and their derived glucosides stigmasterol ?-d-glucoside and ?-sitosterol ?-d-glucoside among various plant parts because they have been identified in cycad flour and have been shown to elicit neurodegenerative outcomes. All four compounds were common in seeds, sporophylls, pollen, leaves, stems, and roots. Roots contained the greatest concentration of both free sterols, and photosynthetic leaflet tissue contained the greatest concentration of both steryl glucosides. Concentration within the three stem tissue categories was low compared to other organs. Reproductive sporophyll tissue contained free sterols similar to seeds, but greater concentration of steryl glucosides than seeds. One of the glucosides was absent from pollen. Concentration in young seeds was higher than old seeds as reported earlier, but concentration did not differ among age categories of leaf, sporophyll, or vascular tissue. The profile differences among the various tissues within these organs may help clarify the physiological role of these compounds. PMID:20157629

Marler, Thomas E.; Shaw, Christopher A.

2010-01-01

9

STEROL METHYLTRANSFERASE 1 Controls the Level of Cholesterol in Plants  

PubMed Central

The side chain in plant sterols can have either a methyl or ethyl addition at carbon 24 that is absent in cholesterol. The ethyl addition is the product of two sequential methyl additions. Arabidopsis contains three genes—sterol methyltransferase 1 (SMT1), SMT2, and SMT3—homologous to yeast ERG6, which is known to encode an S-adenosylmethionine–dependent C-24 SMT that catalyzes a single methyl addition. The SMT1 polypeptide is the most similar of these Arabidopsis homologs to yeast Erg6p. Moreover, expression of Arabidopsis SMT1 in erg6 restores SMT activity to the yeast mutant. The smt1 plants have pleiotropic defects: poor growth and fertility, sensitivity of the root to calcium, and a loss of proper embryo morphogenesis. smt1 has an altered sterol content: it accumulates cholesterol and has less C-24 alkylated sterols content. Escherichia coli extracts, obtained from a strain expressing the Arabidopsis SMT1 protein, can perform both the methyl and ethyl additions to appropriate sterol substrates, although with different kinetics. The fact that smt1 null mutants still produce alkylated sterols and that SMT1 can catalyze both alkylation steps shows that there is considerable overlap in the substrate specificity of enzymes in sterol biosynthesis. The availability of the SMT1 gene and mutant should permit the manipulation of phytosterol composition, which will help elucidate the role of sterols in animal nutrition. PMID:10852933

Diener, Andrew C.; Li, Haoxia; Zhou, Wen-xu; Whoriskey, Wendy J.; Nes, W. David; Fink, Gerald R.

2000-01-01

10

Reminiscences of research on the chemistry and biology of natural sterols in insects, plants and humans  

PubMed Central

Natural sterols often occur as a heterogeneous mixture of homologs, which had disturbed the progress of steroid research. Development and application of GC methodology overcame this difficulty and enabled us to obtain detailed sterol profiles. Together, fine synthesis of stereo-defined isomers and homologs of steroids having oxygenated side chains allowed us to compare them with natural samples as well as to investigate structure-activity relationship. Advance of HPLC technology also facilitated the determination of the stereochemical structure of naturally occurring steroidal compounds, which were obtained only in minute amounts. This review highlights three topics out of our steroid research that have been performed mainly at Tokyo Institute of Technology around 1970–1990. These are sterol metabolism in insects focusing on the mechanism of the conversion of plant sterols to cholesterol and ecdysone biosynthesis, the synthesis and biochemical research of active forms of vitamin D3 derivatives, and the synthesis and microanalysis of plant hormone brassinosteroids. PMID:24126284

IKEKAWA, Nobuo; FUJIMOTO, Yoshinori; ISHIGURO, Masaji

2013-01-01

11

Quantification of sterol lipids in plants by quadrupole time-of-flight mass spectrometry  

PubMed Central

Glycerolipids, sphingolipids, and sterol lipids constitute the major lipid classes in plants. Sterol lipids are composed of free and conjugated sterols, i.e., sterol esters, sterol glycosides, and acylated sterol glycosides. Sterol lipids play crucial roles during adaption to abiotic stresses and plant-pathogen interactions. Presently, no comprehensive method for sterol lipid quantification in plants is available. We used nanospray ionization quadrupole-time-of-flight mass spectrometry (Q-TOF MS) to resolve and identify the molecular species of all four sterol lipid classes from Arabidopsis thaliana. Free sterols were derivatized with chlorobetainyl chloride. Sterol esters, sterol glycosides, and acylated sterol glycosides were ionized as ammonium adducts. Quantification of molecular species was achieved in the positive mode after fragmentation in the presence of internal standards. The amounts of sterol lipids quantified by Q-TOF MS/MS were validated by comparison with results obtained with TLC/GC. Quantification of sterol lipids from leaves and roots of phosphate-deprived A. thaliana plants revealed changes in the amounts and molecular species composition. The Q-TOF method is far more sensitive than GC or HPLC. Therefore, Q-TOF MS/MS provides a comprehensive strategy for sterol lipid quantification that can be adapted to other tandem mass spectrometers. PMID:21382968

Wewer, Vera; Dombrink, Isabel; vom Dorp, Katharina; Dörmann, Peter

2011-01-01

12

Protective Role of Plant Sterol and Stanol Esters in Liver Inflammation: Insights from Mice and Humans  

PubMed Central

The inflammatory component of non–alcoholic steatohepatitis (NASH) can lead to irreversible liver damage. Therefore there is an urgent need to identify novel interventions to combat hepatic inflammation. In mice, omitting cholesterol from the diet reduced hepatic inflammation. Considering the effects of plant sterol/stanol esters on cholesterol metabolism, we hypothesized that plant sterol/stanol esters reduces hepatic inflammation. Indeed, adding plant sterol/stanol esters to a high-fat-diet reduced hepatic inflammation as indicated by immunohistochemical stainings and gene expression for inflammatory markers. Finally, adding sterol/stanol esters lowered hepatic concentrations of cholesterol precursors lathosterol and desmosterol in mice, which were highly elevated in the HFD group similarly as observed in severely obese patients with NASH. In vitro, in isolated LPS stimulated bone marrow derived macrophages desmosterol activated cholesterol efflux whereas sitostanol reduced inflammation. This highly interesting observation that plant sterol/stanol ester consumption leads to complete inhibition of HFD-induced liver inflammation opens new venues in the treatment and prevention of hepatic inflammation. PMID:25356831

Plat, Jogchum; Hendrikx, Tim; Bieghs, Veerle; Jeurissen, Mike L. J.; Walenbergh, Sofie M. A.; van Gorp, Patrick J.; De Smet, Els; Konings, Maurice; Vreugdenhil, Anita C. E.; Guichot, Yasmin Dias; Rensen, Sander S.; Buurman, Wim A.; Greve, Jan Willem M.; Lütjohann, Dieter; Mensink, Ronald P.; Shiri-Sverdlov, Ronit

2014-01-01

13

Cholesterol-lowering effect of spreads enriched with microcrystalline plant sterols in hypercholesterolemic subjects  

Microsoft Academic Search

Summary  \\u000a Background Plant sterols have been shown to reduce serum lipid concentrations. The effectiveness is highly dependent on the physical\\u000a state of the plant sterols. By means of a new crystallizing method, plant sterols can be added into dietary fats and oils\\u000a homogeneously. In this fat ingredient, plant sterols are in a microcrystalline form. Aims of the study We investigated

L. I. Christiansen; P. L. A. Lähteenmäki; M. R. Mannelin; T. E. Seppänen-Laakso; R. V. K. Hiltunen; J. K. Yliruusi

2001-01-01

14

Plant phloem sterol content: forms, putative functions, and implications for phloem-feeding insects  

PubMed Central

All eukaryotes contain sterols, which serve as structural components in cell membranes, and as precursors for important hormones. Plant vegetative tissues are known to contain mixtures of sterols, but very little is known about the sterol composition of phloem. Plants are food for many animals, but plant-feeding arthropods (including phloem-feeding insets) are unique among animals in that they have lost the ability to synthesize sterols, and must therefore acquire these essential nutrients from their food, or via endosymbionts. Our paper starts by providing a very brief overview of variation in plant sterol content, and how different sterols can affect insect herbivores, including those specializing on phloem. We then describe an experiment, where we bulk collected phloem sap exudate from bean and tobacco, and analyzed its sterol content. This approach revealed two significant observations concerning phloem sterols. First, the phloem exudate from each plant was found to contain sterols in three different fractions – free sterols, sterols conjugated to lipids (acylated), and sterols conjugated to carbohydrates (glycosylated). Second, for both plants, cholesterol was identified as the dominant sterol in each phloem exudate fraction; the remaining sterols in each fraction were a mixture of common phytosterols. We discuss our phloem exudate sterol profiles in a plant physiology/biochemistry context, and how it relates to the nutritional physiology/ecology of phloem-feeding insects. We close by proposing important next steps that will advance our knowledge concerning plant phloem sterol biology, and how phloem-sterol content might affect phloem-feeding insects. PMID:24069026

Behmer, Spencer T.; Olszewski, Nathan; Sebastiani, John; Palka, Sydney; Sparacino, Gina; Sciarrno, Elizabeth; Grebenok, Robert J.

2013-01-01

15

Plant Oxidosqualene Metabolism: Cycloartenol Synthase–Dependent Sterol Biosynthesis in Nicotiana benthamiana  

PubMed Central

The plant sterol pathway exhibits a major biosynthetic difference as compared with that of metazoans. The committed sterol precursor is the pentacyclic cycloartenol (9?,19-cyclolanost-24-en-3?-ol) and not lanosterol (lanosta-8,24-dien-3?-ol), as it was shown in the late sixties. However, plant genome mining over the last years revealed the general presence of lanosterol synthases encoding sequences (LAS1) in the oxidosqualene cyclase repertoire, in addition to cycloartenol synthases (CAS1) and to non-steroidal triterpene synthases that contribute to the metabolic diversity of C30H50O compounds on earth. Furthermore, plant LAS1 proteins have been unambiguously identified by peptidic signatures and by their capacity to complement the yeast lanosterol synthase deficiency. A dual pathway for the synthesis of sterols through lanosterol and cycloartenol was reported in the model Arabidopsis thaliana, though the contribution of a lanosterol pathway to the production of 24-alkyl-?5-sterols was quite marginal (Ohyama et al. (2009) PNAS 106, 725). To investigate further the physiological relevance of CAS1 and LAS1 genes in plants, we have silenced their expression in Nicotiana benthamiana. We used virus induced gene silencing (VIGS) based on gene specific sequences from a Nicotiana tabacum CAS1 or derived from the solgenomics initiative (http://solgenomics.net/) to challenge the respective roles of CAS1 and LAS1. In this report, we show a CAS1-specific functional sterol pathway in engineered yeast, and a strict dependence on CAS1 of tobacco sterol biosynthesis. PMID:25343375

Gas-Pascual, Elisabet; Berna, Anne; Bach, Thomas J.; Schaller, Hubert

2014-01-01

16

Plant oxidosqualene metabolism: cycloartenol synthase-dependent sterol biosynthesis in Nicotiana benthamiana.  

PubMed

The plant sterol pathway exhibits a major biosynthetic difference as compared with that of metazoans. The committed sterol precursor is the pentacyclic cycloartenol (9?,19-cyclolanost-24-en-3?-ol) and not lanosterol (lanosta-8,24-dien-3?-ol), as it was shown in the late sixties. However, plant genome mining over the last years revealed the general presence of lanosterol synthases encoding sequences (LAS1) in the oxidosqualene cyclase repertoire, in addition to cycloartenol synthases (CAS1) and to non-steroidal triterpene synthases that contribute to the metabolic diversity of C30H50O compounds on earth. Furthermore, plant LAS1 proteins have been unambiguously identified by peptidic signatures and by their capacity to complement the yeast lanosterol synthase deficiency. A dual pathway for the synthesis of sterols through lanosterol and cycloartenol was reported in the model Arabidopsis thaliana, though the contribution of a lanosterol pathway to the production of 24-alkyl-?(5)-sterols was quite marginal (Ohyama et al. (2009) PNAS 106, 725). To investigate further the physiological relevance of CAS1 and LAS1 genes in plants, we have silenced their expression in Nicotiana benthamiana. We used virus induced gene silencing (VIGS) based on gene specific sequences from a Nicotiana tabacum CAS1 or derived from the solgenomics initiative (http://solgenomics.net/) to challenge the respective roles of CAS1 and LAS1. In this report, we show a CAS1-specific functional sterol pathway in engineered yeast, and a strict dependence on CAS1 of tobacco sterol biosynthesis. PMID:25343375

Gas-Pascual, Elisabet; Berna, Anne; Bach, Thomas J; Schaller, Hubert

2014-01-01

17

Plant Sterols and Stanols as Cholesterol-Lowering Ingredients in Functional Foods  

Microsoft Academic Search

This article reviews developments related to the use of plant sterols and stanols as cholesterol-lowering ingredients in foods and nutraceuticals preparations. Plant sterols and stanols are extracted from the deodorizer distillates of vegetable oil refining and from tall oil, a by-product of paper pulping industry. Plant sterols\\/stanols inhibit cholesterol absorption possibly by competitively inhibiting its incorporation into the mixed micelles

Afaf Kamal-Eldin; Ali Moazzami

2009-01-01

18

The lipid lowering effect of plant sterol ester capsules in hypercholesterolemic subjects  

Microsoft Academic Search

BACKGROUND: Foods enriched with phytosterols have been proven to be an effective therapy to improve blood lipid profiles. However, none of the studies have investigated the efficacy in lipid lowering of plant sterol esters (PSE) in capsule form. The objective of this study is to determine if the plant sterol esters (PSE) in capsule form (1.3 grams of PSE\\/day) lowered

Robert V Acuff; David J Cai; Zhi-Ping Dong; Doris Bell

2007-01-01

19

65 FR 54686 - Food Labeling: Health Claims; Plant Sterol/Stanol Esters and Coronary Heart Disease  

Federal Register 2010, 2011, 2012, 2013, 2014

...Plant Sterol/Stanol Esters and Coronary Heart Disease; Interim Final Rule Federal Register...Plant Sterol/Stanol Esters and Coronary Heart Disease AGENCY: Food and Drug Administration...stanol esters and reduced risk of coronary heart disease (CHD). FDA is taking this...

2000-09-08

20

Plant sterols and stanols as cholesterol-lowering ingredients in functional foods.  

PubMed

This article reviews developments related to the use of plant sterols and stanols as cholesterol-lowering ingredients in foods and nutraceuticals preparations. Plant sterols and stanols are extracted from the deodorizer distillates of vegetable oil refining and from tall oil, a by-product of paper pulping industry. Plant sterols/stanols inhibit cholesterol absorption possibly by competitively inhibiting its incorporation into the mixed micelles in the small intestine although other mechanisms can not be excluded. Daily consumption of 1-2 grams of plant sterols or stanols was shown to cause 10-20% reduction in low-density lipoprotein cholesterol (LDL cholesterol). Combinations of plant sterols/stanols with certain lipid-lowering ingredients were shown to potentate their cholesterol-lowering effects and, in some cases, add triacylglycerol-lowering effects. In this article, patents based information is also discussed. PMID:20653521

Kamal-Eldin, Afaf; Moazzami, Ali

2009-01-01

21

Unusual composition of sterols in a phytophagous insect, Mexican bean beetle reared on soybean plants  

Microsoft Academic Search

Three saturated sterols, cholestanol, campestanol, and stigmastanol, constituted 54, 72, and 77% of the total sterols of the\\u000a egg, prepupa, and adult, respectively, of the Mexican bean beetle,Epilachna varivestis (Mulsant), reared on soybean plants. Lathosterol (7-cholesten-3?-ol), possibly formed from cholestanol in this insect, constituted\\u000a 12, 16, and 11.8% of the total sterols isolated from egg, prepupa, and adult, respectively. None

J. A. Svoboda; M. J. Thompson; T. C. Elden; W. E. Robbins

1974-01-01

22

Plant sterols and host plant suitability for generalist and specialist caterpillars Xiangfeng Jing a,  

E-print Network

Plant sterols and host plant suitability for generalist and specialist caterpillars Xiangfeng Jing performance in three economically important caterpillars (Heliothis virescens, Spodoptera exigua, and Manduca for each caterpillar in the first generation, although these were often subtle, and were not consistent

Behmer, Spencer T.

23

Tocopherol, tocotrienol and plant sterol contents of vegetable oils and industrial fats  

Microsoft Academic Search

The tocopherol and tocotrienol (i.e. tocol) and plant sterol contents of 14 vegetable and 9 industrial fats and oils available on the Finnish market in 2005 were determined using NP-HPLC with fluorescence detection (tocols) and GC-FID (plant sterols). Best sources of ?-tocopherol were wheat germ (192mg\\/100g) and sunflower oil (59mg\\/100g). Oils richest in ?-tocopherol were camelina (72mg\\/100g), linseed (52mg\\/100g) and

Heidi Schwartz; Velimatti Ollilainen; Vieno Piironen; Anna-Maija Lampi

2008-01-01

24

Plant sterols: factors affecting their efficacy and safety as functional food ingredients  

PubMed Central

Plant sterols are naturally occurring molecules that humanity has evolved with. Herein, we have critically evaluated recent literature pertaining to the myriad of factors affecting efficacy and safety of plant sterols in free and esterified forms. We conclude that properly solubilized 4-desmetyl plant sterols, in ester or free form, in reasonable doses (0.8–1.0 g of equivalents per day) and in various vehicles including natural sources, and as part of a healthy diet and lifestyle, are important dietary components for lowering low density lipoprotein (LDL) cholesterol and maintaining good heart health. In addition to their cholesterol lowering properties, plant sterols possess anti-cancer, anti-inflammatory, anti-atherogenicity, and anti-oxidation activities, and should thus be of clinical importance, even for those individuals without elevated LDL cholesterol. The carotenoid lowering effect of plant sterols should be corrected by increasing intake of food that is rich in carotenoids. In pregnant and lactating women and children, further study is needed to verify the dose required to decrease blood cholesterol without affecting fat-soluble vitamins and carotenoid status. PMID:15070410

Berger, Alvin; Jones, Peter JH; Abumweis, Suhad S

2004-01-01

25

Plant Sterols as Anticancer Nutrients: Evidence for Their Role in Breast Cancer  

PubMed Central

While many factors are involved in the etiology of cancer, it has been clearly established that diet significantly impacts one’s risk for this disease. More recently, specific food components have been identified which are uniquely beneficial in mitigating the risk of specific cancer subtypes. Plant sterols are well known for their effects on blood cholesterol levels, however research into their potential role in mitigating cancer risk remains in its infancy. As outlined in this review, the cholesterol modulating actions of plant sterols may overlap with their anti-cancer actions. Breast cancer is the most common malignancy affecting women and there remains a need for effective adjuvant therapies for this disease, for which plant sterols may play a distinctive role. PMID:23434903

Grattan, Bruce J.

2013-01-01

26

Effect of plant sterols and tannins on Phytophthora ramorum growth and sporulation.  

PubMed

Elicitin-mediated acquisition of plant sterols is required for growth and sporulation of Phytophthora spp. This study examined the interactions between elicitins, sterols, and tannins. Ground leaf tissue, sterols, and tannin-enriched extracts were obtained from three different plant species (California bay laurel, California black oak, and Oregon white oak) in order to evaluate the effect of differing sterol/tannin contents on Phytophthora ramorum growth. For all three species, high levels of foliage inhibited P. ramorum growth and sporulation, with a steeper concentration dependence for the two oak samples. Phytophthora ramorum growth and sporulation were inhibited by either phytosterols or tannin-enriched extracts. High levels of sterols diminished elicitin gene expression in P. ramorum; whereas the tannin-enriched extract decreased the amount of 'functional' or ELISA-detectable elicitin, but not gene expression. Across all treatment combinations, P. ramorum growth and sporulation correlated strongly with the amount of ELISA-detectable elicitin (R (2)?= 0.791 and 0.961, respectively). PMID:23689874

Stong, Rachel A; Kolodny, Eli; Kelsey, Rick G; González-Hernández, M P; Vivanco, Jorge M; Manter, Daniel K

2013-06-01

27

Plant sterol consumption frequency affects plasma lipid levels and cholesterol kinetics in humans  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background/Objectives: To compare the efficacy of single versus multiple doses of plant sterols on circulating lipid level and cholesterol trafficking. Subjects/Methods: A randomized, placebo-controlled, three-phase (6 days/phase) crossover, supervised feeding trial was conducted in 19 subjects. Sub...

28

66 FR 50824 - Food Labeling: Health Claims; Plant Sterol/Stanol Esters and Coronary Heart Disease  

Federal Register 2010, 2011, 2012, 2013, 2014

...Plant Sterol/Stanol Esters and Coronary Heart Disease AGENCY: Food and Drug Administration...stanol esters and reduced risk of coronary heart disease (CHD). This interim final rule...a recent publication from the American Heart Association (AHA) (Ref. 1)...

2001-10-05

29

Effect of frequency of dosing of plant sterols on plasma cholesterol levels and synthesis rate  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective was to compare the effects of plant sterols (PS) consumed as a single dose (single) at breakfast or as three doses consumed with breakfast, lunch and dinner (divided) on plasma lipoprotien levels and cholesterol endogenous fractional synthesis rate (FSR). A randomized, placebo-controll...

30

Reduction of Cholesterol and Glycoalkaloid Levels in Transgenic Potato Plants by Overexpression of a Type 1 Sterol Methyltransferase cDNA1  

PubMed Central

Transgenic potato (Solanum tuberosum cv Désirée) plants overexpressing a soybean (Glycine max) type 1 sterol methyltransferase (GmSMT1) cDNA were generated and used to study sterol biosynthesis in relation to the production of toxic glycoalkaloids. Transgenic plants displayed an increased total sterol level in both leaves and tubers, mainly due to increased levels of the 24-ethyl sterols isofucosterol and sitosterol. The higher total sterol level was due to increases in both free and esterified sterols. However, the level of free cholesterol, a nonalkylated sterol, was decreased. Associated with this was a decreased glycoalkaloid level in leaves and tubers, down to 41% and 63% of wild-type levels, respectively. The results show that glycoalkaloid biosynthesis can be down-regulated in transgenic potato plants by reducing the content of free nonalkylated sterols, and they support the view of cholesterol as a precursor in glycoalkaloid biosynthesis. PMID:12692338

Arnqvist, Lisa; Dutta, Paresh C.; Jonsson, Lisbeth; Sitbon, Folke

2003-01-01

31

21 CFR 101.83 - Health claims: plant sterol/stanol esters and risk of coronary heart disease (CHD).  

Code of Federal Regulations, 2012 CFR

... (A) The claim states that plant sterol... (B) The claim states that diets that include...does not imply that consumption of diets that include...developed by Unilever United States, Inc...byproducts of the kraft paper pulping...

2012-04-01

32

21 CFR 101.83 - Health claims: plant sterol/stanol esters and risk of coronary heart disease (CHD).  

Code of Federal Regulations, 2013 CFR

... (A) The claim states that plant sterol... (B) The claim states that diets that include...does not imply that consumption of diets that include...developed by Unilever United States, Inc...byproducts of the kraft paper pulping...

2013-04-01

33

21 CFR 101.83 - Health claims: plant sterol/stanol esters and risk of coronary heart disease (CHD).  

Code of Federal Regulations, 2011 CFR

... (A) The claim states that plant sterol... (B) The claim states that diets that include...does not imply that consumption of diets that include...developed by Unilever United States, Inc...byproducts of the kraft paper pulping...

2011-04-01

34

21 CFR 101.83 - Health claims: plant sterol/stanol esters and risk of coronary heart disease (CHD).  

Code of Federal Regulations, 2010 CFR

... (A) The claim states that plant sterol... (B) The claim states that diets that include...does not imply that consumption of diets that include...developed by Unilever United States, Inc...byproducts of the kraft paper pulping...

2010-04-01

35

21 CFR 101.83 - Health claims: plant sterol/stanol esters and risk of coronary heart disease (CHD).  

Code of Federal Regulations, 2014 CFR

... (A) The claim states that plant sterol... (B) The claim states that diets that include...does not imply that consumption of diets that include...developed by Unilever United States, Inc...byproducts of the kraft paper pulping...

2014-04-01

36

Reduced-calorie orange juice beverage with plant sterols lowers C-reactive protein concentrations and improves the lipid profile in  

Microsoft Academic Search

Background: Dietary plant sterols effectively reduce LDL choles- terol when incorporated into fat matrices. We showed previously that supplementation with orange juice containing plant sterols (2 g\\/d) significantly reduced LDL cholesterol. Inflammation is pivotal inatherosclerosis.High-sensitivityC-reactiveprotein(hs-CRP),the prototypic marker of inflammation, is a cardiovascular disease risk marker; however, there is a paucity of data on the effect of plant sterols on CRP

Sridevi Devaraj; Bryce C Autret; Ishwarlal Jialal

37

START lipid/sterol-binding domains are amplified in plants and are predominantly associated with homeodomain transcription factors  

PubMed Central

Background In animals, steroid hormones regulate gene expression by binding to nuclear receptors. Plants lack genes for nuclear receptors, yet genetic evidence from Arabidopsis suggests developmental roles for lipids/sterols analogous to those in animals. In contrast to nuclear receptors, the lipid/sterol-binding StAR-related lipid transfer (START) protein domains are conserved, making them candidates for involvement in both animal and plant lipid/sterol signal transduction. Results We surveyed putative START domains from the genomes of Arabidopsis, rice, animals, protists and bacteria. START domains are more common in plants than in animals and in plants are primarily found within homeodomain (HD) transcription factors. The largest subfamily of HD-START proteins is characterized by an HD amino-terminal to a plant-specific leucine zipper with an internal loop, whereas in a smaller subfamily the HD precedes a classic leucine zipper. The START domains in plant HD-START proteins are not closely related to those of animals, implying collateral evolution to accommodate organism-specific lipids/sterols. Using crystal structures of mammalian START proteins, we show structural conservation of the mammalian phosphatidylcholine transfer protein (PCTP) START domain in plants, consistent with a common role in lipid transport and metabolism. We also describe putative START-domain proteins from bacteria and unicellular protists. Conclusions The majority of START domains in plants belong to a novel class of putative lipid/sterol-binding transcription factors, the HD-START family, which is conserved across the plant kingdom. HD-START proteins are confined to plants, suggesting a mechanism by which lipid/sterol ligands can directly modulate transcription in plants. PMID:15186492

Schrick, Kathrin; Nguyen, Diana; Karlowski, Wojciech M; Mayer, Klaus FX

2004-01-01

38

Unique pathways of sterol metabolism in the Mexican bean beetle, a plant-feeding insect  

Microsoft Academic Search

Radiolabeled sterols,14C-cholesterol,14C-cholestanol,3H-stigmasterol,3H-stigmastanol, and3H-sitosterol, were fed to larvae of the Mexican bean beetle,Epilachna varivestis Mulsant, by coating soybean leaves. Free sterol and sterol ester fractions from treated insects were isolated and analyzed,\\u000a and in each case nearly 30% or more of total radiolabeled sterols retained by the insect were found in the sterol ester fraction\\u000a after 8 days. ?5 sterols were

J. A. Svoboda; M. J. Thompson; W. E. Robbins; T. C. Elden

1975-01-01

39

Intake of a Single Morning Dose of Standard and Novel Plant Sterol Preparations for 4 Weeks Does Not Dramatically Affect Plasma Lipid Concentrations in Humans  

Technology Transfer Automated Retrieval System (TEKTRAN)

Recommendations for decreasing the risk of developing cardiovascular disease include increasing the intake of plant sterols and fish oil. The cholesterol-lowering action of plant sterols, when provided in a fish-oil fatty acids vehicle, remains to be investigated in humans. A randomized, crossover-f...

40

Effects of plant sterols and stanols on lipid metabolism and cardiovascular risk.  

PubMed

Functional foods enriched with plant sterols and stanols are on sale in many countries. Due to their structural similarity with cholesterol, these additives lower intestinal absorption of cholesterol, resulting in a 10-15% reduction in LDL-cholesterol when their daily intakes are 2-3 g. They are also effective as part of a cholesterol-lowering diet and in combination with cholesterol-lowering drugs. Estimates for the absorption of plant sterols (sitosterol and campesterol) and of campestanol are around 10%, and for sitostanol less than 5%. Lipid-standardized plasma levels are very low, but increase when statins are used. Extensive toxicological evaluation studies have not revealed any harmful side-effects. In human studies, side-effects were comparable to placebo treatment. However, lipid-standardized levels of the hydrocarbon carotenoids may decrease, without leaving the normal range. Together, these findings indicate that these functional foods have great potential in the prevention of coronary heart disease. However, post-marketing surveillance for example for functional foods in general is necessary to monitor possible adverse effects and describe consumers and consumption patterns. PMID:11383323

Plat, J; Mensink, R P

2001-02-01

41

SHORT-TERM EFFICACY OF PLANT STEROLS CONSUMED AT BREAKFAST OR AT EACH MEAL IN LOWERING BLOOD CHOLESTEROL LEVELS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Objective: To compare under controlled conditions the effect of plant sterol consumed as a single morning dose or divided through the day on blood lipid profile. Method: A randomized, placebo-controlled, crossover-feeding, single blind trial was conducted in 19 subjects with LDL- cholesterol level...

42

Gonopodial morphogenesis in female mosquitofish, Gambusia affinis affinis , masculinized by exposure to degradation products from plant sterols  

Microsoft Academic Search

Female mosquitofish,Gambusia affinis affinis, were masculinized by exposure to degradation products (presumably steroids) of the plant sterol, stigmastanol. Masculinization was indicated by the induction of a male-like gonopodium in each specimen. The morphogenetic stages of gonopodial development are discussed as are the anatomical specializations produced in the mature gonopodial tip.

W. Mike Howell; Thomas E. Denton

1989-01-01

43

Plant sterol oxides in functional beverages: influence of matrix and storage.  

PubMed

Three plant sterol (PS)-enriched beverages, milk based fruit juice (MFJPS), fruit juice (FJPS) and milk beverage (MPS), were stored at 4, 24, or 37 °C and analysed at regular time intervals of 2 months until 6 months. PS stability was analysed from the production of phytosterol oxidation products (POPs). The ?-sitosterol oxides (7?/7?-hydroxy, ?/?-epoxy, triol, and 7-keto) and campesterol oxides (?/?-epoxy, and 7-keto) were detected in all beverages and at all storage times and temperatures. Total POP contents followed the order MPS?FJPS>MFJPS. In general, the beverages showed low PS oxidation levels (<0.17%). Predictive models of POP content versus storage time were established. These models explain total POP content by over 75% and individual POP content by over 50%. We propose 7-ketositosterol and 7-ketocampesterol as PS oxidation markers during storage of beverages of this kind. PMID:25466102

González-Larena, Marina; Garcia-Llatas, Guadalupe; Clemente, Gonzalo; Barberá, Reyes; Lagarda, María Jesús

2015-04-15

44

Genetic variation in plant CYP51s confers resistance against voriconazole, a novel inhibitor of brassinosteroid-dependent sterol biosynthesis.  

PubMed

Brassinosteroids (BRs) are plant steroid hormones with structural similarity to mammalian sex steroids and ecdysteroids from insects. The BRs are synthesized from sterols and are essential regulators of cell division, cell elongation and cell differentiation. In this work we show that voriconazole, an antifungal therapeutic drug used in human and veterinary medicine, severely impairs plant growth by inhibiting sterol-14?-demethylation and thereby interfering with BR production. The plant growth regulatory properties of voriconazole and related triazoles were identified in a screen for compounds with the ability to alter BR homeostasis. Voriconazole suppressed growth of the model plant Arabidopsis thaliana and of a wide range of both monocotyledonous and dicotyledonous plants. We uncover that voriconazole toxicity in plants is a result of a deficiency in BRs that stems from an inhibition of the cytochrome P450 CYP51, which catalyzes a step of BR-dependent sterol biosynthesis. Interestingly, we found that the woodland strawberry Fragaria vesca, a member of the Rosaceae, is naturally voriconazole resistant and that this resistance is conferred by the specific CYP51 variant of F. vesca. The potential of voriconazole as a novel tool for plant research is discussed. PMID:23335967

Rozhon, Wilfried; Husar, Sigrid; Kalaivanan, Florian; Khan, Mamoona; Idlhammer, Markus; Shumilina, Daria; Lange, Theo; Hoffmann, Thomas; Schwab, Wilfried; Fujioka, Shozo; Poppenberger, Brigitte

2013-01-01

45

Genetic Variation in Plant CYP51s Confers Resistance against Voriconazole, a Novel Inhibitor of Brassinosteroid-Dependent Sterol Biosynthesis  

PubMed Central

Brassinosteroids (BRs) are plant steroid hormones with structural similarity to mammalian sex steroids and ecdysteroids from insects. The BRs are synthesized from sterols and are essential regulators of cell division, cell elongation and cell differentiation. In this work we show that voriconazole, an antifungal therapeutic drug used in human and veterinary medicine, severely impairs plant growth by inhibiting sterol-14?-demethylation and thereby interfering with BR production. The plant growth regulatory properties of voriconazole and related triazoles were identified in a screen for compounds with the ability to alter BR homeostasis. Voriconazole suppressed growth of the model plant Arabidopsis thaliana and of a wide range of both monocotyledonous and dicotyledonous plants. We uncover that voriconazole toxicity in plants is a result of a deficiency in BRs that stems from an inhibition of the cytochrome P450 CYP51, which catalyzes a step of BR-dependent sterol biosynthesis. Interestingly, we found that the woodland strawberry Fragaria vesca, a member of the Rosaceae, is naturally voriconazole resistant and that this resistance is conferred by the specific CYP51 variant of F. vesca. The potential of voriconazole as a novel tool for plant research is discussed. PMID:23335967

Rozhon, Wilfried; Husar, Sigrid; Kalaivanan, Florian; Khan, Mamoona; Idlhammer, Markus; Shumilina, Daria; Lange, Theo; Hoffmann, Thomas; Schwab, Wilfried; Fujioka, Shozo; Poppenberger, Brigitte

2013-01-01

46

Sterol requirement of Mycoplasma capricolum.  

PubMed Central

Mycoplasmas require an external source of sterol for growth. For Mycoplasma capricolum this requirement is met not only by cholesterol but also by the methylcholestane derivatives lanosterol, cycloartenol, 4,4-dimethylcholesterol, and 4beta-methylcholestanol. Cholesteryl methyl ether and 3alpha-methylcholestanol serve equally well as sterol supplements. None of the growth-supporting sterol derivatives tested was metabolically modified. The unusual acceptance of diverse cholestane derivatives by a mycoplasma species contrasts with the structural attributes thought to be necessary for sterol function in eukaryotic membranes. PMID:279900

Odriozola, J M; Waitzkin, E; Smith, T L; Bloch, K

1978-01-01

47

Effect of free plant sterols in low-fat milk on serum lipid profile in hypercholesterolemic subjects  

Microsoft Academic Search

Objective: To determine the effect of nonesterified, nonhydrogenated plant sterols solubilized in a partly vegetable oil-filled low-fat milk on serum low-density lipoprotein cholesterol (LDL) in mildly hypercholesterolemic patients.Design: Double-blind, randomized, placebo-controlled three-arm crossover study.Setting: Outpatient clinical trial.Subjects: A total of 138 patients were screened, providing 81 patients for randomization; 71 patients completed the study.Interventions: The study product was a 500

A B Thomsen; H B Hansen; C Christiansen; H Green; A Berger

2004-01-01

48

Sterols of the fungi - Distribution and biosynthesis.  

NASA Technical Reports Server (NTRS)

The importance of sterols in the growth and reproduction in fungi is becoming increasingly apparent. This article concerns the composition and biosynthesis of ergosterol in these organisms. Comparison to plant and animal sterol formation are made.

Weete, J. D.

1973-01-01

49

Sterols of the fungi - Distribution and biosynthesis  

NASA Technical Reports Server (NTRS)

The importance of sterols in the growth and reproduction in fungi is becoming increasingly apparent. This article concerns the composition and biosynthesis of ergosterol in these organisms. Comparison to plant and animal sterol formation are made.

Weete, J. D.

1973-01-01

50

Sterols of a contemporary lacustrine sediment. [in English postglacial lake  

NASA Technical Reports Server (NTRS)

Results are reported for detailed sterol analyses of several depths (corresponding to between zero and about 150 yr in age) in a contemporary lacustrine sediment from a freshwater lake of postglacial origin in England. Delta 5-, delta 22-, and delta 5,22-sterols are identified along with 5 alpha- and 5 beta-stanols as well as a C26 stanol with a C7 side chain. Solvent extraction yields carbon number distributions for the 5 alpha- and 5 beta-stanol sediment constituents that parallel the corresponding delta 5-sterol distributions. The amounts of 5 alpha-stanols are found to exceed those of 5 beta-stanols in the sediment, and variations in the ratio of 5 alpha- to 5 beta-stanol between sediment samples from similar depths are shown to suggest an inhomogeneity of the sediment. It is found that the sterol composition of sediment cores varies markedly with depth, reflecting both the effects of a sterol hydrogenation process and a changing input to the sediment. It is concluded that C29 sterols, of probable higher-plant origin, predominate at lower sediment depths while C27 sterols, possibly derived from autochthonous sources, are more abundant in the surface sediment.

Gaskell, S. J.; Eglinton, G.

1976-01-01

51

Determination of plant stanols and plant sterols in phytosterol enriched foods with a gas chromatographic-flame ionization detection method: NMKL collaborative study.  

PubMed

This collaborative study with nine participating laboratories was conducted to determine the total plant sterol and/or plant stanol contents in phytosterol fortified foods with a gas chromatographic method. Four practice and 12 test samples representing mainly commercially available foodstuffs were analyzed as known replicates. Twelve samples were enriched with phytosterols, whereas four samples contained only natural contents of phytosterols. The analytical procedure consisted of two alternative approaches: hot saponification method, and acid hydrolysis treatment prior to hot saponification. As a result, sterol/stanol compositions and contents in the samples were measured. The amounts of total plant sterols and total plant stanols varying from 0.005 to 8.04 g/100 g product were statistically evaluated after outliers were eliminated. The repeatability RSD (RSDr) varied from 1.34 to 17.13%. The reproducibility RSD (RSDR) ranged from 3.03 to 17.70%, with HorRat values ranging from 0.8 to 2.1. When only phytosterol enriched food test samples are considered, the RSDr ranged from 1.48 to 6.13%, the RSD, ranged from 3.03 to 7.74%, and HorRat values ranged from 0.8 to 2.1. Based on the results of this collaborative study, the study coordinator concludes the method is fit for its purpose. PMID:25145144

Laakso, Päivi H

2014-01-01

52

Fish-oil esters of plant sterols differ from vegetable-oil sterol esters in triglycerides lowering, carotenoid bioavailability and impact on plasminogen activator inhibitor-1 (PAI-1) concentrations in hypercholesterolemic subjects  

Microsoft Academic Search

BACKGROUND: Consumption of plant sterol (PS) esters lower low-density lipoprotein (LDL)-cholesterol levels by suppressing intestinal absorption of cholesterol. Commercially available PS are mainly esterified to omega-6 fatty acid (FA), such as sunflower oil (SO) FA. Emerging trends include using other sources such as olive oil (OO) or omega-3 FA from fish oil (FO), known to exert potent hypotriglyceridemic effects. Our

Peter JH Jones; Isabelle Demonty; Yen-Ming Chan; Yael Herzog; Dori Pelled

2007-01-01

53

Degradation of sterols and terrigenous organic matter in waters of the Mackenzie Shelf, Canadian Arctic  

E-print Network

of these two sterols to terrigenous vascular plants. A good corre- lation was observed between the extent. To explain the specific induction of autoxidation on vascular plant-derived material, a mechanism involving higher plant debris increasing the proportion of highly degraded vascular plant material in the SPM

54

Cloning, functional expression and phylogenetic analysis of plant sterol 24C-methyltransferases involved in sitosterol biosynthesis.  

PubMed

Sterol 24C-methyltransferases (SMTs) constitute a group of sequence-related proteins that catalyze the distinct patterns of 24-alkyl sterols that occur throughout nature. Two SMT cDNAs (SMT2-1 and SMT2-2) were cloned by homology based PCR methods from young leaves of Glycine max (soybean) and the corresponding enzymes were expressed functionally in Escherichia coli. The full-length cDNA for SMT2-1 and SMT2-2 have open reading frames of 1086 bp and 1092 bp, respectively, and encode proteins of 361 and 363 residues with a calculated molecular mass of 40.3 and 40.4 kDa, respectively. The substrate preference of the two isoforms was similar yet they differed from SMT1; kinetically SMT2-1 and SMT2-2 generated k(cat) values for the optimal substrate 24(28)methylene lophenol of 0.8 min(-1) and 1.34 min(-1), respectively, compared to the activity of SMT1 that generated a k(cat) for the optimal substrate cycloartenol of 0.6 min(-1). SMT2-2 was purified to homogeneity and the subunit organization shown to be tetrameric in similar fashion to other cloned SMTs. Analysis of the accumulated products catalyzed by the recombinant enzymes demonstrated that soybean SMT2-1 and SMT2-2 operate transalkylation activities analogous to the soybean plant SMT1. Metabolite analyses correlated with transcript profiling of the three SMT isoforms during soybean maturation clearly demonstrated that SMT isoform expression determines specific C24-methyl to C24-ethyl ratios to flowering whereas with seed development there is a disconnection such that the SMT transcript levels decrease against an increase in sterol content; generally SMT2-2 is expressed more than SMT2-1 or SMT1. These observations suggest that the genes that encode SMT1 and SMT2 in sitosterol biosynthesis may have undergone divergent evolution. In support of this proposition, the genomic organization for SMT1 of fungi and protozoa align very closely with one another and to those of the plant SMT2; both sets of SMTs lack introns. Unexpectedly, the SMT1 from Glycine max and other embryophytes of diverse origin possess disparate intron-exon characteristics that can be shown relates back to the algae. Our results suggest that the order of SMT1 appearing before SMT2 in phytosterol synthesis arose recently in plant evolution in response to duplication of a more primitive SMT gene likely to have been bifunctional and catalytically promiscuous. PMID:19818974

Neelakandan, Anjanasree K; Song, Zhihong; Wang, Junqing; Richards, Matthew H; Wu, Xiaolei; Valliyodan, Babu; Nguyen, Henry T; Nes, W David

2009-12-01

55

Sterols as biomarkers in the surface microlayer of the estuarine areas.  

PubMed

This study aims to determine the concentration of sterols used as biomarkers in the surface microlayer (SML) in estuarine areas of the Selangor River, Malaysia. Samples were collected during different seasons through the use of a rotation drum. The analysis of sterols was performed using gas chromatography equipped with a flame ionisation detector (GC-FID). The results showed that the concentrations of total sterols in the SML ranged from 107.06 to 505.55ngL(-1). The total sterol concentration was found to be higher in the wet season. Cholesterol was found to be the most abundant sterols component in the SML. The diagnostic ratios of sterols show the influence of natural sources and waste on the contribution of sterols in the SML. Further analysis, using principal component analysis (PCA), showed distinct inputs of sterols derived from human activity (40.58%), terrigenous and plant inputs (22.59%) as well as phytoplankton and marine inputs (17.35%). PMID:25682566

Alsalahi, Murad Ali; Latif, Mohd Talib; Ali, Masni Mohd; Dominick, Doreena; Khan, Md Firoz; Mustaffa, Nur Ili Hamizah; Nadzir, Mohd Shahrul Mohd; Nasher, Essam; Zakaria, Mohamad Pauzi

2015-04-15

56

Sterol-Dependent Induction of Plant Defense Responses by a Microbe-Associated Molecular Pattern from Trichoderma viride1[W][OPEN  

PubMed Central

Plant-microbe interactions involve numerous regulatory systems essential for plant defense against pathogens. An ethylene-inducing xylanase (Eix) of Trichoderma viride is a potent elicitor of plant defense responses in specific cultivars of tobacco (Nicotiana tabacum) and tomato (Solanum lycopersicum). We demonstrate that tomato cyclopropyl isomerase (SlCPI), an enzyme involved in sterol biosynthesis, interacts with the LeEix2 receptor. Moreover, we examined the role of SlCPI in signaling during the LeEix/Eix defense response. We found that SlCPI is an important factor in the regulation of the induction of defense responses such as the hypersensitive response, ethylene biosynthesis, and the induction of pathogenesis-related protein expression in the case of LeEix/Eix. Our results also suggest that changes in the sterol composition reduce LeEix internalization, thereby attenuating the induction of plant defense responses. PMID:24351686

Sharfman, Miya; Bar, Maya; Schuster, Silvia; Leibman, Meirav; Avni, Adi

2014-01-01

57

Higher sterol content regulated by CYP51 with concomitant lower phospholipid content in membranes is a common strategy for aluminium tolerance in several plant species  

PubMed Central

Several studies have shown that differences in lipid composition and in the lipid biosynthetic pathway affect the aluminium (Al) tolerance of plants, but little is known about the molecular mechanisms underlying these differences. Phospholipids create a negative charge at the surface of the plasma membrane and enhance Al sensitivity as a result of the accumulation of positively charged Al3+ ions. The phospholipids will be balanced by other electrically neutral lipids, such as sterols. In the present research, Al tolerance was compared among pea (Pisum sativum) genotypes. Compared with Al-tolerant genotypes, the Al-sensitive genotype accumulated more Al in the root tip, had a less intact plasma membrane, and showed a lower expression level of PsCYP51, which encodes obtusifoliol-14?-demethylase (OBT 14DM), a key sterol biosynthetic enzyme. The ratio of phospholipids to sterols was higher in the sensitive genotype than in the tolerant genotypes, suggesting that the sterol biosynthetic pathway plays an important role in Al tolerance. Consistent with this idea, a transgenic Arabidopsis thaliana line with knocked-down AtCYP51 expression showed an Al-sensitive phenotype. Uniconazole-P, an inhibitor of OBT 14DM, suppressed the Al tolerance of Al-tolerant genotypes of maize (Zea mays), sorghum (Sorghum bicolor), rice (Oryza sativa), wheat (Triticum aestivum), and triticale (×Triticosecale Wittmark cv. Currency). These results suggest that increased sterol content, regulated by CYP51, with concomitant lower phospholipid content in the root tip, results in lower negativity of the plasma membrane. This appears to be a common strategy for Al tolerance among several plant species. PMID:25416794

Wagatsuma, Tadao; Khan, Md. Shahadat Hossain; Watanabe, Toshihiro; Maejima, Eriko; Sekimoto, Hitoshi; Yokota, Takao; Nakano, Takeshi; Toyomasu, Tomonobu; Tawaraya, Keitaro; Koyama, Hiroyuki; Uemura, Matsuo; Ishikawa, Satoru; Ikka, Takashi; Ishikawa, Akifumi; Kawamura, Takeshi; Murakami, Satoshi; Ueki, Nozomi; Umetsu, Asami; Kannari, Takayuki

2015-01-01

58

Higher sterol content regulated by CYP51 with concomitant lower phospholipid content in membranes is a common strategy for aluminium tolerance in several plant species.  

PubMed

Several studies have shown that differences in lipid composition and in the lipid biosynthetic pathway affect the aluminium (Al) tolerance of plants, but little is known about the molecular mechanisms underlying these differences. Phospholipids create a negative charge at the surface of the plasma membrane and enhance Al sensitivity as a result of the accumulation of positively charged Al(3+) ions. The phospholipids will be balanced by other electrically neutral lipids, such as sterols. In the present research, Al tolerance was compared among pea (Pisum sativum) genotypes. Compared with Al-tolerant genotypes, the Al-sensitive genotype accumulated more Al in the root tip, had a less intact plasma membrane, and showed a lower expression level of PsCYP51, which encodes obtusifoliol-14?-demethylase (OBT 14DM), a key sterol biosynthetic enzyme. The ratio of phospholipids to sterols was higher in the sensitive genotype than in the tolerant genotypes, suggesting that the sterol biosynthetic pathway plays an important role in Al tolerance. Consistent with this idea, a transgenic Arabidopsis thaliana line with knocked-down AtCYP51 expression showed an Al-sensitive phenotype. Uniconazole-P, an inhibitor of OBT 14DM, suppressed the Al tolerance of Al-tolerant genotypes of maize (Zea mays), sorghum (Sorghum bicolor), rice (Oryza sativa), wheat (Triticum aestivum), and triticale (×Triticosecale Wittmark cv. Currency). These results suggest that increased sterol content, regulated by CYP51, with concomitant lower phospholipid content in the root tip, results in lower negativity of the plasma membrane. This appears to be a common strategy for Al tolerance among several plant species. PMID:25416794

Wagatsuma, Tadao; Khan, Md Shahadat Hossain; Watanabe, Toshihiro; Maejima, Eriko; Sekimoto, Hitoshi; Yokota, Takao; Nakano, Takeshi; Toyomasu, Tomonobu; Tawaraya, Keitaro; Koyama, Hiroyuki; Uemura, Matsuo; Ishikawa, Satoru; Ikka, Takashi; Ishikawa, Akifumi; Kawamura, Takeshi; Murakami, Satoshi; Ueki, Nozomi; Umetsu, Asami; Kannari, Takayuki

2015-02-01

59

Plant derived veterinary vaccines  

Microsoft Academic Search

Infectious diseases remain one of the main causes of death and economic losses in animals despite the fact that prophylactic\\u000a vaccination has been extremely successful in disease prevention. New effective viral, bacterial and parasitic vaccines are\\u000a needed, but unfortunately production costs still remain prohibitive. In this respect plants can offer a valid alternative.\\u000a Production of antigenic proteins in plants relies

L. Santi

2009-01-01

60

Effect of low-fat, fermented milk enriched with plant sterols on serum lipid profile and oxidative stress in moderate hypercholesterolemia13  

Microsoft Academic Search

Background: Plant sterol (PS)-enriched foods have been shown to reduce plasma LDL-cholesterol concentrations. In most studies, however, PSs were incorporated into food products of high fat content. Objective: We examined the effect of daily consumption of PS- supplemented low-fat fermented milk (FM) on the plasma lipid profile and on systemic oxidative stress in hypercholesterolemic subjects. Design: Hypercholesterolemic subjects (LDL-cholesterol concen-

Boris Hansel; Catherine Nicolle; Florent Lalanne; Francoise Tondu; Taous Lassel; Yves Donazzolo; Jean Ferričres; Michel Krempf; Jean-Louis Schlienger; Bruno Verges; M John Chapman; Eric Bruckert

61

Arabidopsis Sterol Endocytosis Involves Actin-Mediated Trafficking via ARA6Positive Early Endosomes  

Microsoft Academic Search

Background: In contrast to the intense attention devoted to research on intracellular sterol trafficking in animal cells, knowledge about sterol transport in plant cells remains limited, and virtually nothing is known about plant endocytic sterol trafficking. Similar to animals, biosynthetic sterol transport occurs from the endoplasmic reticulum (ER) via the Golgi apparatus to the plasma membrane. The vesicle trafficking inhibitor

Markus Grebe; Jian Xu; Wiebke Möbius; Takashi Ueda; Akihiko Nakano; Hans J. Geuze; Martin B. Rook; B. J. G. Scheres

2003-01-01

62

The hydroxyanilide fenhexamid, a new sterol biosynthesis inhibitor fungicide efficient against the plant pathogenic fungus Botryotinia fuckeliana (Botrytis cinerea).  

PubMed

Fenhexamid, a recently developed botryticide, is shown here to inhibit sterol biosynthesis. When the fungus Botryotinia fuckeliana was grown in the presence of fenhexamid, the ergosterol content was reduced, and three 3-keto compounds, 4 alpha-methylfecosterone, fecosterone and episterone, accumulated, suggesting an inhibition of the 3-keto reductase involved in C-4 demethylation. Thus, fenhexamid belongs to a new, promising class of sterol biosynthesis inhibitors not previously used in agriculture or in medicine. PMID:11721524

Debieu, D; Bach, J; Hugon, M; Malosse, C; Leroux, P

2001-11-01

63

Antioxidant activity of phenolic compounds added to a functional emulsion containing omega-3 fatty acids and plant sterol esters.  

PubMed

The effect of eleven compounds extracted from red propolis on the oxidative stability of a functional emulsion was evaluated. Emulsions prepared with Echium oil as omega 3 (?-3 FA) source, containing 1.63g/100mL of ?-linolenic acid (ALA), 0.73g/100mL of stearidonic acid (SDA) and 0.65g/100mL of plant sterol esters (PSE) were prepared without or with phenolic compounds (vanillic acid, caffeic acid, trans-cinnamic acid, 2,4-dihydroxycinnamic acid, p-coumaric acid, quercetin, trans-ferulic acid, trans,trans-farnesol, rutin, gallic acid or sinapic acid). tert-Butylhydroquinone and a mixture containing ascorbic acid and FeSO4 were applied as negative and positive controls of the oxidation. Hydroperoxide, thiobarbituric acid reactive substances (TBARS), malondialdehyde and phytosterol oxidation products (POPs) were evaluated as oxidative markers. Based on hydroperoxide and TBARS analysis, sinapic acid and rutin (200ppm) showed the same antioxidant activity than TBHQ, representing a potential alternative as natural antioxidant to be applied in a functional emulsion containing ?-3 FA and PSE. PMID:25842314

Espinosa, Raquel Rainho; Inchingolo, Raffaella; Alencar, Severino Matias; Rodriguez-Estrada, Maria Teresa; Castro, Inar Alves

2015-09-01

64

Plant phloem sterol content: forms, putative functions, and implications for phloem-feeding insects  

E-print Network

and asparagine in the rice plant, endogenous factors related to resis- tance against the brown planthop- per (Nilaparvata-Lugens). Agricu. Biol. Chem. 46, 2877?2879. doi: 10.1271/bbb1961.46.2877 Svoboda, J. A. (1999). Variabil- ity of metabolism...

Behmer, Spencer T.; Olszewski, Nathan; Sebastiani, John; Palka, Sydney; Sparacino, Gina; Sciarrno, Elizabeth; Grebenok, Robert J.

2013-09-24

65

The sterols of the echinoderm Asterias rubens  

PubMed Central

1. Twenty-two sterols were identified in the starfish Asterias rubens (Phylum, Echinodermata; Class, Asteroidea). 2. The major 4-demethyl sterols had a ?7 bond and the C27 compound 5?-cholest-7-en-3?-ol predominated over other mono- and di-unsaturated sterols belonging to the C26, C27, C28 and C29 series. 3. Small amounts of cholest-5-en-3?-ol and 5?-cholestan-3?-ol were also present. 4. The minor sterols identified all contained either one or two methyl groups at C-4 and are considered to be potential biosynthetic precursors of 5?-cholest-7-en-3?-ol. 5. Three sterols possessing a 9?,19-cyclopropane ring were also isolated and were probably derived by the starfish from a dietary source. PMID:4772271

Smith, Andrew G.; Rubinstein, Ian; Goad, L. John

1973-01-01

66

Intake occasion affects the serum cholesterol lowering of a plant sterol-enriched single-dose yoghurt drink in mildly hypercholesterolaemic subjects  

Microsoft Academic Search

Objective:To determine the impact of intake occasion (with or without a meal), and product fat level on the cholesterol-lowering efficacy of a plant sterol (PS)-enriched (3 g\\/day) single-dose yoghurt drink.Design:Double-blind, randomized, placebo-controlled, parallel study with a 4 weeks run-in and 4 weeks intervention period.Setting:Subjects recruited from the general community.Subjects:A total of 184 moderate hypercholesterolaemic subjects (81 men and 103 women)

A M E Doornbos; E M Meynen; G S M J E Duchateau; H C M van der Knaap; E A Trautwein

2006-01-01

67

Plant-Derived Transfer DNAs  

PubMed Central

The transfer of DNA from Agrobacterium to plant cell nuclei is initiated by a cleavage reaction within the 25-bp right border of Ti plasmids. In an effort to develop all-native DNA transformation vectors, 50 putative right border alternatives were identified in both plant expressed sequence tags and genomic DNA. Efficacy tests in a tobacco (Nicotiana tabacum) model system demonstrated that 14 of these elements displayed at least 50% of the activity of conventional Agrobacterium transfer DNA borders. Four of the most effective plant-derived right border alternatives were found to be associated with intron-exon junctions. Additional elements were embedded within introns, exons, untranslated trailers, and intergenic DNA. Based on the identification of a single right border alternative in Arabidopsis and three in rice (Oryza sativa), the occurrence of this motif was estimated at a frequency of at least 0.8×10?8. Modification of plasmid DNA sequences flanking the alternative borders demonstrated that both upstream and downstream sequences play an important role in initiating DNA transfer. Optimal DNA transfer required the elements to be preceded by pyrimidine residues interspaced by AC-rich trinucleotides. Alteration of this organization lowered transformation frequencies by 46% to 93%. Despite their weaker resemblance with left borders, right border alternatives also functioned effectively in terminating DNA transfer, if both associated with an upstream A[C/T]T[C/G]A[A/T]T[G/T][C/T][G/T][C/G]A[C/T][C/T][A/T] domain and tightly linked cytosine clusters at their junctions with downstream DNA. New insights in border region requirements were used to construct an all-native alfalfa (Medicago sativa) transfer DNA vector that can be used for the production of intragenic plants. PMID:16244143

Rommens, Caius M.; Bougri, Oleg; Yan, Hua; Humara, Jaime M.; Owen, Joanna; Swords, Kathy; Ye, Jingsong

2005-01-01

68

Plant sterol-enriched margarines and reduction of plasma total- and LDL-cholesterol concentrations in normocholesterolaemic and mildly hypercholesterolaemic subjects  

Microsoft Academic Search

Objectives: To compare effects on plasma total-, LDL-, and HDL-cholesterol concentrations of margarines enriched with different vegetable oil sterols or sitostanol-ester.Design: A randomized double-blind placebo-controlled balanced incomplete Latin square design with five treatments and four periods of 3.5 weeks. Margarines enriched with sterols from soybean, sheanut or ricebran oil or with sitostanol-ester were compared to a non-enriched control margarine. Sterol

JA Weststrate; GW Meijer

1998-01-01

69

Effects of margarine enriched with plant sterol esters from rapeseed and tall oils on markers of endothelial function, inflammation and hemostasis.  

PubMed

Abstract Background and aims. The sterol profile of rapeseed oil differs from that of tall oil with higher contents of campesterol and brassicasterol. We previously found that margarines providing 2 g/day of sterols from rapeseed or tall oil resulted in similar reductions in LDL cholesterol of 8-9%. The aim of the present study was to investigate whether the consumption of these margarines affected markers of endothelial function, inflammation and hemostasis. Methods. Blood samples were collected from 58 hypercholesterolemic volunteers who completed a double-blinded, randomized, crossover trial. Subjects consumed each of the two sterol margarines and a control non-sterol margarine for 4 weeks separated by one-week washout periods. All the margarines had the same fatty acid composition. Concentrations of vascular cell adhesion molecule-l (VCAM-1), E-selectin, circulating tumor necrosis factor ? (TNF?) and plasminogen activator inhibitor-1 (total, tPAI-1; active, PAI-1) were quantified. Results. Rapeseed-sterol margarine reduced E-selectin concentrations compared to the control margarine (p = 0.012) while tall-sterol margarine had no effect. The rapeseed-sterol margarine also reduced tPAI-1 (p = 0.008) compared to the tall-sterol margarine. No significant changes were observed in TNF? and VCAM-1. No association was found between LDL reduction and changes in E-selectin and tPAI-1. Conclusion. Rapeseed-sterol margarine demonstrated favorable effects on vascular risk markers. PMID:25553599

Heggen, Eli; Kirkhus, Bente; Pedersen, Jan I; Tonstad, Serena

2015-04-01

70

A ncovel angiogenic factor derived from Aloe vera gel: ?-sitosterol, a plant sterol  

Microsoft Academic Search

Aloe vera gel has a beneficial effect on wound healing. Because angiogenesis is an essential process in wound healing, we hypothesized\\u000a that Aloe vera gel might contain potent angiogenic compounds. Here we demonstrate that Aloe vera gel and its extracts are angiogenic on the chorioallantoic membrane (CAM) of chick embryo. Out of the three compounds purified\\u000a from the final fraction

Eun-Joung Moon; You Mie Lee; Ok-Hee Lee; Myoung-Jin Lee; Seung-Ki Lee; Myung-Hee Chung; Young-In Park; Chung-Ki Sung; Jae-Soo Choi; Kyu-Won Kim

1999-01-01

71

Fish-oil esters of plant sterols differ from vegetable-oil sterol esters in triglycerides lowering, carotenoid bioavailability and impact on plasminogen activator inhibitor-1 (PAI-1) concentrations in hypercholesterolemic subjects  

PubMed Central

Background Consumption of plant sterol (PS) esters lower low-density lipoprotein (LDL)-cholesterol levels by suppressing intestinal absorption of cholesterol. Commercially available PS are mainly esterified to omega-6 fatty acid (FA), such as sunflower oil (SO) FA. Emerging trends include using other sources such as olive oil (OO) or omega-3 FA from fish oil (FO), known to exert potent hypotriglyceridemic effects. Our objective was to compare the actions of different FA esterified to PS on blood lipids, carotenoid bioavailability as well as inflammatory and coagulation markers. Methods Twenty-one moderately overweight, hypercholesterolemic subjects consumed experimental isoenergetic diets enriched with OO (70% of fat), each lasting 28-day and separated by 4-week washout periods, using a randomized crossover design. Diets were supplemented with three PS esters preparations, PS-FO, PS-SO, or PS-OO. All PS treatments contained an equivalent of 1.7 PS g/d, and the PS-FO provided a total of 5.4 g/d FO FA (eicosapentaenoic and docosahexaenoic acids). Results There were no differences between PS-containing diet effects on total cholesterol, LDL-cholesterol, or high-density lipoprotein (HDL)-cholesterol levels. However, PS-FO consumption resulted in markedly lower (P < 0.0001) fasting and postprandial triglyceride concentrations compared with PS-SO and PS-OO. These treatments affected plasma ?-carotene (P = 0.0169) and retinol (P = 0.0244), but not tocopherol (P = 0.2108) concentrations. Consumption of PS-FO resulted in higher ?-carotene (P = 0.0139) and retinol (P = 0.0425) levels than PS-SO and PS-OO, respectively. Plasma TNF-?, IL-6, C-reactive protein, prostate specific antigen, and fibrinogen concentrations were unaffected by the PS-interventions. In contrast, plasminogen activator inhibitor 1 (PAI-1) concentrations were lower (P = 0.0282) in the PS-FO-fed than the PS-SO, but not the PS-OO (P = 0.7487) groups. Conclusion Our findings suggest that, in hypercholesterolemic subjects consuming an OO-based diet, PS-FO results in lowered blood triglyceride and PAI-1 concentrations, and higher fat-soluble vitamin levels in comparison to the vegetable oil FA esters of PS (PS-SO and PS-OO). Thus, PS-FO may offer hyperlipidemic subjects a more comprehensive lipid lowering approach while reducing the potential risk of decreased plasma carotenoid concentrations. PMID:17961204

Jones, Peter JH; Demonty, Isabelle; Chan, Yen-Ming; Herzog, Yael; Pelled, Dori

2007-01-01

72

Effects of plant sterol and stanol ester consumption on lipid metabolism, antioxidant status and markers of oxidative stress, endothelial function and low-grade inflammation in patients on current statin treatment  

Microsoft Academic Search

Objective:The present study was designed to examine for the first time, side-by-side, the effects of plant sterol and stanol consumption on lipid metabolism and markers of antioxidant status, oxidative stress, endothelial dysfunction and low-grade inflammation in subjects on stable statin–treatment.Design:Double-blind, randomized, placebo-controlled, intervention trial.Setting:University.Subjects:Forty-five patients on current statin treatment were recruited via newspaper advertisements. Data of 41 patients were used

A De Jong; J Plat; A Bast; R W L Godschalk; S Basu; R P Mensink

2008-01-01

73

Sterols and sterol glycosides of Bryonia alba  

Microsoft Academic Search

It has been shown that the roots ofBryonia alba contain cholest-7-en-3ß-ol, 24-methylcholest-7-en-3ß-ol, 24-ethylcholest-7-en-3ß-ol, 24-methylenecholest-7-en-3ß-ol, 24-ethylidenecholest-7-en-3ß-ol, 24-ethyl-4-methylcholest-7-en-3ß-ol, 24-ethylidene-4-methylcholest-7-en-3ß-ol, and also previously undescribed 3-O-ß-glucopyranosides of the above-mentioned sterols.

A. G. Panosyan; G. M. Avetisyan; V. A. Mnatsakanyan

1977-01-01

74

Final report of the amended safety assessment of PEG-5, -10, -16, -25, -30, and -40 soy sterol.  

PubMed

PEGs Soy Sterol are polyethylene glycol (PEG) derivatives of soybean oil sterols used in a variety of cosmetic formulations as surfactants and emulsifying agents, skin-conditioning agents, and cleansing and solubilizing agents. When the safety of these ingredients were first reviewed, the available data were insufficient to support safety. New data have since been received and the safety of these ingredients in cosmetics has been substantiated. Current concentration of use ranges from a low of 0.05% in makeup preparations to 2% in moisturizers and several other products. PEGs Soy Sterol are produced by the reaction of the soy sterol hydroxyl with ethylene oxide. In general, ethoxylated fatty acids can contain 1,4-dioxane as a byproduct of ethoxylation. The soy sterols include campesterol, stigmasterol, and beta-sitosterol. The distribution of sterols found in oils derived from common plants is similar, with beta-sitosterol comprising a major component. Impurities include sterol hydrocarbons and cholesterol (4% to 6%) and triterpine alcohols, keto-steroids, and other steroid-like substances (4% to 6%). No pesticide residues were detected. PEGS: Because PEGs are an underlying structure in PEGs Soy Sterols, the previous assessment of PEGs was considered. It is generally recognized that the PEG monomer, ethylene glycol, and certain of its monoalkyl ethers are reproductive and developmental toxins. Given the methods of manufacture of PEGs Soy Sterol, there is no likelihood of ethylene glycol or its alkyl ethers being present. Also, the soybean oil sterol ethers in this ingredient are chemically different from the ethylene glycol alkyl ethers of concern. PEGs are not carcinogenic, although sensitization and nephrotoxicity were observed in burn patients treated with a PEG-based cream. No evidence of systemic toxicity or sensitization was found in studies with intact skin. Plant Phytosterols: Intestinal absorption of ingested plant phytosterols is on the order of 5%, with 95% of the material entering the colon. Absorbed plant phytosterols are transported to the blood. Although there are some data suggesting that sulfates of beta-sitosterol can act as abortifacients in rats and rabbits, other studies of well-characterized plant phytosterols and phytosterol esters demonstrated no effect in an estrogen-binding study, a recombinant yeast assay for estrogen or estrogen-like activity, or a juvenile rat uterotrophic assay for estrogen or estrogen-like activity. In a two-generation reproduction study using rats, plant phytosterol esters in the diet had no effect on any parameter of reproduction or fertility. Subcutaneous injections of beta-sitosterol did reduce sperm concentrations and fertility in rats. Sitosterol inhibited tumor promoting activity of 12-O-tetradecanoylphorbol-13-acetate (TPA) in mice after initiation with 7,12-dimethylbenz[a]anthracene (DMBA), and reduced the tumors produced by N-methylnitrosourea in rats. Phytosterols were not genotoxic in several bacterial, mammalian, and in vitro assay systems. Phytosterols decreased epithelial cell proliferation in the colon of mice and rats, and were cytotoxic for human epidermoid carcinoma of the nasopharynx. PEGs Soy Sterols: The acute oral LD50 in rats of PEG-5-25 Soy Sterol was >10 g/kg. The acute dermal LD50 of a liquid eyeliner containing 2%PEG-5 Soy Sterol was >2 g/kg in rabbits. PEG-5-25 Soy Sterol was not a primary irritant in rabbits when applied undiluted. Undiluted PEG-5 Soy Sterol did not cause sensitization in guinea pigs. PEGs Soy Sterol did not produce ocular toxicity in rabbits. PEG-5 Soy Sterol was negative in the Ames mutagenicity test, with or without metabolic activation. PEG-5 Soy Sterol, at concentrations up to 2%in formulation, did not cause dermal or ocular irritation, dermal sensitization, or photosensitization in clinical studies. Because of the possible presence of 1,4-dioxane reaction product and unreacted ethylene oxide residues, it was considered necessary to use appropriate procedures to remove these from PEGs Soy Sterol before blending them

2004-01-01

75

Sterol Glycosyltransferases—The Enzymes That Modify Sterols  

Microsoft Academic Search

Sterols are important components of cell membranes, hormones, signalling molecules and defense-related biotic and abiotic\\u000a chemicals. Sterol glycosyltransferases (SGTs) are enzymes involved in sterol modifications and play an important role in metabolic\\u000a plasticity during adaptive responses. The enzymes are classified as a subset of family 1 glycosyltransferases due to the presence\\u000a of a signature motif in their primary sequence. These

Pankaj Chaturvedi; Pratibha Misra; Rakesh Tuli

76

Arabidopsis ERG28 Tethers the Sterol C4-Demethylation Complex to Prevent Accumulation of a Biosynthetic Intermediate That Interferes with Polar Auxin Transport[C][W  

PubMed Central

Sterols are vital for cellular functions and eukaryotic development because of their essential role as membrane constituents. Sterol biosynthetic intermediates (SBIs) represent a potential reservoir of signaling molecules in mammals and fungi, but little is known about their functions in plants. SBIs are derived from the sterol C4-demethylation enzyme complex that is tethered to the membrane by Ergosterol biosynthetic protein28 (ERG28). Here, using nonlethal loss-of-function strategies focused on Arabidopsis thaliana ERG28, we found that the previously undetected SBI 4-carboxy-4-methyl-24-methylenecycloartanol (CMMC) inhibits polar auxin transport (PAT), a key mechanism by which the phytohormone auxin regulates several aspects of plant growth, including development and responses to environmental factors. The induced accumulation of CMMC in Arabidopsis erg28 plants was associated with diagnostic hallmarks of altered PAT, including the differentiation of pin-like inflorescence, loss of apical dominance, leaf fusion, and reduced root growth. PAT inhibition by CMMC occurs in a brassinosteroid-independent manner. The data presented show that ERG28 is required for PAT in plants. Furthermore, it is accumulation of an atypical SBI that may act to negatively regulate PAT in plants. Hence, the sterol pathway offers further prospects for mining new target molecules that could regulate plant development. PMID:24326590

Mialoundama, Alexis Samba; Jadid, Nurul; Brunel, Julien; Di Pascoli, Thomas; Heintz, Dimitri; Erhardt, Mathieu; Mutterer, Jérôme; Bergdoll, Marc; Ayoub, Daniel; Van Dorsselaer, Alain; Rahier, Alain; Nkeng, Paul; Geoffroy, Philippe; Miesch, Michel; Camara, Bilal; Bouvier, Florence

2013-01-01

77

A Comparison of the Packing Behavior of Egg Phosphatidylcholine with Cholesterol and Biogenically Related Sterols in Langmuir Monolayer Films  

PubMed Central

Cholesterol and selected derivatives were studied as mixed Langmuir monolayers with egg phosphatidylcholine (PC). As an extension of our earlier work, which employed binary sterol/PC mixtures, here we examined ternary mixed monolayers containing cholesterol along with an alternate sterol and PC in different molar ratios, using pressure-area isotherms. The ternary systems behaved similarly to the binary sterol/PC systems reported previously, with similar condensation noted for the sterol/PC films. To better understand how variations in sterol structure affect sterol packing in such membrane monolayers, binary mixtures containing cholestenone, cholestanol, and lanosterol with PC were also studied. Cholestanol behaved similarly to cholesterol when incorporated with PC, while cholestenone and lanosterol did not cause as much film condensation. The observed differences in molecular packing, and attributed sterol structural differences, are considered within the context of sterol/phospholipid mixtures in biological membranes. PMID:19524563

Lintker, Kimberly Borrenpohl; Kpere-Daibo, Peter; Fliesler, Steven J.; Serfis, Alexa Barnoski

2009-01-01

78

Free and glycosylated sterol bioaccumulation in developing Cycas micronesica seeds  

PubMed Central

The bioaccumulation of free and glycosylated forms of stigmasterol and ?-sitosterol were determined from Cycas micronesica K.D. Hill seeds throughout seed ontogeny. Per-seed pool of the four compounds increased linearly from 2 to 24 months, indicating no developmental period elicited a major shift in the rate of bioaccumulation. The slopes were not homogeneous, signifying a change in relative sterol profile concomitant with seed maturation. This shift was in favour of the glucosides, as their rate of accumulation exceeded that of the free sterols. Stigmasterol content exceeded that of ?-sitosterol, but ontogeny did not influence the ratio of these dominant sterols. The quantity and quality of sterol exposure during consumption of foods prepared from gametophytes by humans is strongly influenced by age of harvested seeds. Results are critical for a further understanding of the link between human neurodegenerative diseases and historical consumption of foods derived from the seed gametophyte tissue. PMID:20157628

Marler, Thomas E.; Shaw, Christopher A.

2010-01-01

79

A high oleic sunflower oil fatty acid esters of plant sterols mixed with dietary diacylglycerol reduces plasma insulin and body fat accumulation in Psammomys obesus  

PubMed Central

Background Metabolic syndrome is associated with subsequent development of cardiovascular diseases and type 2 diabetes. It is characterized by reduced response to insulin, central obesity, and dyslipidemia. Intake of plant sterols (PS) has been shown to confer a healthier lipid profile and ameliorate cardiovascular disease risk factors in experimental animals and humans. In this study we used an animal model of type 2 diabetes to assess the effects of a preparation of PS esterified to high oleic sunflower oil fatty acids mixed with dietary diacylglycerol (PS-HOSO) on diabetic related metabolic parameters. Psammomys obesus (P. obesus) were fed high energy (HE) diet supplemented by either PS-HOSO or control oil. Following 4.5 weeks of intervention, animals were divided into fasting and non-fasting modes prior to outcome measurements. Glucose and insulin levels as well as blood lipid profile, body weight, and fat accumulation were evaluated in fasting and non-fasting modes. Results P. obesus fed with a HE diet displayed a characteristic heterogeneity in their blood glucose and insulin levels with a subset group displaying type 2 diabetes symptoms. PS-HOSO treatment significantly reduced total cholesterol (24%, P < 0.001) and non-HDL cholesterol (34%, P < 0.01) compared to the control diet. Among fasting animals, body weight at end point and epididymal fat-to-liver weight ratio were significantly (P < 0.05 each) reduced (7% and 16%, respectively) compared to controls. Interestingly, fasting blood glucose levels were similar between groups, whereas plasma insulin level at end point was 44% lower in the PS-HOSO group compared to control group (P < 0.0001) Conclusion PS-HOSO supplementation to diabetes-prone gerbils counteracts the increase in body weight and epididymal fat accumulation, and also results in a drop in circulating insulin levels. These effects are pointing out that PS-HOSO may serve as a functional ingredient for metabolic syndrome or diabetic sufferers, which not only influences body weight, but also prevents or reverses insulin resistance and hyperlipidemia. PMID:19822001

Ziv, Ehud; Patlas, Natan; Kalman, Rony; Pelled, Dori; Herzog, Yael; Dror, Tali; Cohen, Tzafra

2009-01-01

80

Lactoferrin-derived resistance against plant pathogens in transgenic plants.  

PubMed

Lactoferrin (LF) is a ubiquitous cationic iron-binding milk glycoprotein that contributes to nutrition and exerts a broad-spectrum primary defense against bacteria, fungi, protozoa, and viruses in mammals. These qualities make lactoferrin protein and its antimicrobial motifs highly desirable candidates to be incorporated in plants to impart broad-based resistance against plant pathogens or to economically produce them in bulk quantities for pharmaceutical and nutritional purposes. This study introduced bovine LF (BLF) gene into tobacco ( Nicotiana tabacum var. Xanthi), Arabidopsis ( A. thaliana ) and wheat ( Triticum aestivum ) via Agrobacterium -mediated plant transformation. Transgenic plants or detached leaves exhibited high levels of resistance against the damping-off causing fungal pathogen Rhizoctonia solani and the head blight causing fungal pathogen Fusarium graminearum . LF also imparted resistance to tomato plants against a bacterial pathogen, Ralstonia solanacearum . Similarly, other researchers demonstrated expression of LF and LF-mediated high-quality resistance to several other aggressive fungal and bacterial plant pathogens in transgenic plants and against viral pathogens by foliar applications of LF or its derivatives. Taken together, these studies demonstrated the effectiveness of LF for improving crop quality and its biopharming potentials for pharmaceautical and nutritional applications. PMID:23889215

Lakshman, Dilip K; Natarajan, Savithiry; Mandal, Sudhamoy; Mitra, Amitava

2013-12-01

81

Survival strategies of a sterol auxotroph  

PubMed Central

The high sterol concentration in eukaryotic cell membranes is thought to influence membrane properties such as permeability, fluidity and microdomain formation. Drosophila cannot synthesize sterols, but do require them for development. Does this simply reflect a requirement for sterols in steroid hormone biosynthesis, or is bulk membrane sterol also essential in Drosophila? If the latter is true, how do they survive fluctuations in sterol availability and maintain membrane homeostasis? Here, we show that Drosophila require both bulk membrane sterol and steroid hormones in order to complete adult development. When sterol availability is restricted, Drosophila larvae modulate their growth to maintain membrane sterol levels within tight limits. When dietary sterol drops below a minimal threshold, larvae arrest growth and development in a reversible manner. Strikingly, membrane sterol levels in arrested larvae are dramatically reduced (dropping sixfold on average) in most tissues except the nervous system. Thus, sterols are dispensable for maintaining the basic membrane biophysical properties required for cell viability; these functions can be performed by non-sterol lipids when sterols are unavailable. However, bulk membrane sterol is likely to have essential functions in specific tissues during development. In tissues in which sterol levels drop, the overall level of sphingolipids increases and the proportion of different sphingolipid variants is altered. These changes allow survival, but not growth, when membrane sterol levels are low. This relationship between sterols and sphingolipids could be an ancient and conserved principle of membrane homeostasis. PMID:20940226

Carvalho, Maria; Schwudke, Dominik; Sampaio, Julio L.; Palm, Wilhelm; Riezman, Isabelle; Dey, Gautam; Gupta, Gagan D.; Mayor, Satyajit; Riezman, Howard; Shevchenko, Andrej; Kurzchalia, Teymuras V.; Eaton, Suzanne

2010-01-01

82

Sterol Biosynthesis Is Required for Heat Resistance but Not Extracellular Survival in Leishmania  

PubMed Central

Sterol biosynthesis is a crucial pathway in eukaryotes leading to the production of cholesterol in animals and various C24-alkyl sterols (ergostane-based sterols) in fungi, plants, and trypanosomatid protozoa. Sterols are important membrane components and precursors for the synthesis of powerful bioactive molecules, including steroid hormones in mammals. Their functions in pathogenic protozoa are not well characterized, which limits the development of sterol synthesis inhibitors as drugs. Here we investigated the role of sterol C14?-demethylase (C14DM) in Leishmania parasites. C14DM is a cytochrome P450 enzyme and the primary target of azole drugs. In Leishmania, genetic or chemical inactivation of C14DM led to a complete loss of ergostane-based sterols and accumulation of 14-methylated sterols. Despite the drastic change in lipid composition, C14DM-null mutants (c14dm?) were surprisingly viable and replicative in culture. They did exhibit remarkable defects including increased membrane fluidity, failure to maintain detergent resistant membrane fraction, and hypersensitivity to heat stress. These c14dm? mutants showed severely reduced virulence in mice but were highly resistant to itraconazole and amphotericin B, two drugs targeting sterol synthesis. Our findings suggest that the accumulation of toxic sterol intermediates in c14dm? causes strong membrane perturbation and significant vulnerability to stress. The new knowledge may help improve the efficacy of current drugs against pathogenic protozoa by exploiting the fitness loss associated with drug resistance. PMID:25340392

Xu, Wei; Hsu, Fong-Fu; Baykal, Eda; Huang, Juyang; Zhang, Kai

2014-01-01

83

Dietary sterols/steroids and the generalist caterpillar Helicoverpa zea: physiology, biochemistry and midgut gene expression.  

PubMed

Sterols are essential nutrients for insects because, in contrast to mammals, no insect (or arthropod for that matter) can synthesize sterols de novo. Plant-feeding insects typically generate their sterols, commonly cholesterol, by metabolizing phytosterols. However, not all phytosterols are readily converted to cholesterol. In this study we examined, using artificial diets containing single sterols/steroids, how typical (cholesterol and stigmasterol) and atypical (cholestanol and cholestanone) sterols/steroids affect the performance of a generalist caterpillar (Helicoverpa zea). We also performed sterols/steroids analyses, using GC/MS techniques, to explore the metabolic fate of these different dietary sterols/steroids. Finally, we used a microarray approach to measure, and compare, midgut gene expression patterns that arise as a function of dietary sterols/steroids. In general, H. zea performed best on the cholesterol and stigmasterol diets, with cholesterol as the dominant tissue sterol on these two treatments. Compared to the cholesterol and stigmasterol diets, performance was reduced on the cholestanol and cholestanone diets; on these latter treatments stanols were the dominant tissue sterol. Finally, midgut gene expression patterns differed as a function of dietary sterol/steroid; using the cholesterol treatment as a reference, gene expression differences were smallest on stigmasterol, intermediate on cholestanol, and greatest on cholestanone. Inspection of our data revealed two broad insights. First, they identify a number of genes potentially involved in sterol/steroid metabolism and absorption. Second, they provide unique mechanistic insights into how variation in dietary sterol/steroid structure can affect insect herbivores. PMID:22898624

Jing, Xiangfeng; Vogel, Heiko; Grebenok, Robert J; Zhu-Salzman, Keyan; Behmer, Spencer T

2012-11-01

84

Sterol C24-methyltransferase: Physio- and stereo-chemical features of the sterol C3 group required for catalytic competence.  

PubMed

Sterol C24-methyltransferases (24-SMTs) catalyze the electrophilic alkylation of ?(24)-sterols to a variety of sterol side chain constructions, and the C3- moiety is the primary determinant for substrate binding by these enzymes. To determine what specific structural features of the C3-polar group ensure sterol catalysis, a series of structurally related C3-analogs of lanosterol that differed in stereochemistry, bulk and electronic properties were examined against the fungal 24-SMT from Paracoccidioides brasiliensis (Pb) which recognize lanosterol as the natural substrate. Analysis of the magnitude of sterol C24-methylation activity (based on the kinetic constants of V(max)/K(m) and product distributions determined by GC-MS) resulting from changes at the C3-position in which the 3?-OH was replaced by 3?-OH, 3?-acetyl, 3-oxo, 3-OMe, 3?-F, 3?-NH(2) (protonated species) or 3H group revealed that lanosterol and five substrate analogs were catalyzed and yielded identical side chain products whereas neither the 3H- or 3?-OH lanosterol derivatives were productively bound. Taken together, our results demonstrate a chemical complementarity involving hydrogen bonding formation of specific active site contacts to the nucleophilic C3-group of sterol is required for proper orientation of the substrate C-methyl intermediate in the activated complex. PMID:22446159

Howard, Alicia L; Liu, Jialin; Elmegeed, Gamal A; Collins, Emily K; Ganatra, Kalgi S; Nwogwugwu, Chizaram A; Nes, W David

2012-05-01

85

Osh proteins regulate membrane sterol organization but are not required for sterol movement between the ER and PM  

PubMed Central

Sterol transport between the endoplasmic reticulum (ER) and plasma membrane (PM) occurs by an ATP-dependent, non-vesicular mechanism that is presumed to require sterol transport proteins (STPs). In Saccharomyces cerevisiae, homologues of the mammalian oxysterol-binding protein (Osh1–7) have been proposed to function as STPs. To evaluate this proposal we took two approaches. First we used dehydroergosterol (DHE) to visualize sterol movement in living cells by fluorescence microscopy. DHE was introduced into the PM under hypoxic conditions and observed to redistribute to lipid droplets on growing the cells aerobically. Redistribution required ATP and the sterol acyltransferase Are2, but did not require PM-derived transport vesicles. DHE redistribution occurred robustly in a conditional yeast mutant (osh? osh4-1ts) that lacks all functional Osh proteins at 37°C. In a second approach we used a pulse-chase protocol to analyze the movement of metabolically radiolabeled ergosterol from the ER to the PM. Arrival of radiolabeled ergosterol at the PM was assessed in isolated PM-enriched fractions as well by extracting sterols from intact cells with methyl-?-cyclodextrin. These experiments revealed that whereas ergosterol is transported effectively from the ER to the PM in Osh-deficient cells, the rate at which it moves within the PM to equilibrate with the methyl-?-cyclodextrin extractable sterol pool is slowed. We conclude (i) that the role of Osh proteins in nonvesicular sterol transport between the PM, ER and lipid droplets is either minimal, or subsumed by other mechanisms and (ii) that Osh proteins regulate the organization of sterols at the PM. PMID:21689253

Georgiev, Alexander; Sullivan, David P.; Kersting, Michael C.; Dittman, Jeremy S.; Beh, Christopher T.; Menon, Anant K.

2011-01-01

86

Plasma membrane sterol complexation, generated by filipin, triggers signaling responses in tobacco cells  

Microsoft Academic Search

The effects of changes in plasma membrane (PM) sterol lateral organization and availability on the control of signaling pathways have been reported in various animal systems, but rarely assessed in plant cells. In the present study, the pentaene macrolide antibiotic filipin III, commonly used in animal systems as a sterol sequestrating agent, was applied to tobacco cells. We show that

Laurent Bonneau; Patricia Gerbeau-Pissot; Dominique Thomas; Christophe Der; Jeannine Lherminier; Stéphane Bourque; Yann Roche; Françoise Simon-Plas

2010-01-01

87

The physiology of sterol nutrition in the pea aphid Acyrthosiphon pisum Sophie Bouvaine a  

E-print Network

The physiology of sterol nutrition in the pea aphid Acyrthosiphon pisum Sophie Bouvaine a , Spencer Keywords: Acyrthosiphon pisum Aphid Cholesterol Sterol Phloem sap Phytosterol a b s t r a c t The phloem sap of fava bean (Vicia faba) plants utilized by the pea aphid Acyrthosiphon pisum contains three

Behmer, Spencer T.

88

Propiconazole inhibits the sterol 14?-demethylase in Glomus irregulare like in phytopathogenic fungi.  

PubMed

The increasing concentrations impact (0.02, 0.2 and 2 mg L(-1)) of a Sterol Biosynthesis Inhibitor (SBI) fungicide, propiconazole, was evaluated on development and sterol metabolism of two non-target organisms: mycorrhizal or non-mycorrhizal transformed chicory roots and the arbuscular mycorrhizal fungus (AMF) Glomus irregulare using monoxenic cultures. In this work, we provide the first evidence of a direct impact of propiconazole on the AMF by disturbing its sterol metabolism. A significant decrease in end-products sterols contents (24-methylcholesterol and in 24-ethylcholesterol) was observed concomitantly to a 24-methylenedihydrolanosterol accumulation indicating the inhibition of a key enzyme in sterol biosynthesis pathway, the sterol 14?-demethylase like in phytopathogenic fungi. A decrease in end-product sterol contents in propiconazole-treated roots was also observed suggesting a slowing down of the sterol metabolism in plant. Taken together, our findings suggest that the inhibition of the both AM symbiotic partners development by propiconazole results from their sterol metabolism alterations. PMID:22239944

Calonne, Maryline; Sahraoui, Anissa Lounčs-Hadj; Campagnac, Estelle; Debiane, Djouher; Laruelle, Frédéric; Grandmougin-Ferjani, Anne; Fontaine, Joël

2012-04-01

89

Tracking the sterol biosynthesis pathway of the diatom Phaeodactylum tricornutum.  

PubMed

Diatoms are unicellular photosynthetic microalgae that play a major role in global primary production and aquatic biogeochemical cycling. Endosymbiotic events and recurrent gene transfers uniquely shaped the genome of diatoms, which contains features from several domains of life. The biosynthesis pathways of sterols, essential compounds in all eukaryotic cells, and many of the enzymes involved are evolutionarily conserved in eukaryotes. Although well characterized in most eukaryotes, the pathway leading to sterol biosynthesis in diatoms has remained hitherto unidentified. Through the DiatomCyc database we reconstructed the mevalonate and sterol biosynthetic pathways of the model diatom Phaeodactylum tricornutum in silico. We experimentally verified the predicted pathways using enzyme inhibitor, gene silencing and heterologous gene expression approaches. Our analysis revealed a peculiar, chimeric organization of the diatom sterol biosynthesis pathway, which possesses features of both plant and fungal pathways. Strikingly, it lacks a conventional squalene epoxidase and utilizes an extended oxidosqualene cyclase and a multifunctional isopentenyl diphosphate isomerase/squalene synthase enzyme. The reconstruction of the P. tricornutum sterol pathway underscores the metabolic plasticity of diatoms and offers important insights for the engineering of diatoms for sustainable production of biofuels and high-value chemicals. PMID:24996048

Fabris, Michele; Matthijs, Michiel; Carbonelle, Sophie; Moses, Tessa; Pollier, Jacob; Dasseville, Renaat; Baart, Gino J E; Vyverman, Wim; Goossens, Alain

2014-11-01

90

Insect molting hormone and sterol biosynthesis in spinach  

SciTech Connect

Insect molting hormones, which are produced by plants and are effective molecules in the control of insect crop pests, are biosynthesized in developing spinach leaves (Spinacia oleracea L.). The major sterols biosynthesized by spinach are avenasterol (24{alpha}-ethyl-5{alpha}-cholesta-7,24(28)-dien-3{beta}-ol), spinasterol (24{alpha}-ethyl-5{alpha}-cholesta-7,22-dien-3{beta}-ol), and 22-dihydrospinasterol (24{alpha}-ethyl-5{alpha}-cholest-7-en-3{beta}-ol). The major ecdysteroids biosynthesized are ecdysterone (2{beta},3{beta},14{alpha},20R,22R,25-hexahydroxy-5{beta}-cholest-7-en-6-one) and polypodine B (2{beta},3{beta},5{beta},14{alpha},20R,22R,25-heptahycroxycholest-7-en-6-one) and polypodine B (2{beta},3{beta},5{beta},14{alpha},20R,22R,25-heptahydroxycholest-7-en-6-one). When labeled 2-{sup 14}C-mevalonic acid was incorporated into young leaves isolated squalene, sterols and ecdysteroids contained the label. During a short (16 h) incorporation period in intact young leaves of 100 day old plants, the avenasterol has the highest specific activity in counts per minute per {mu}g of sterol followed by 22-dihydrospinasterol which is more highly labeled than spinasterol. The ecdysteroids synthesized, on an entire plant basis, account for 20% of the total steroid (sterol and ecdysteroid) isolated from the plant.

Grebenok, R.J.; Adler, J.H. (Michigan Technological Univ., Houghton (USA))

1990-05-01

91

Non-vesicular sterol transport in cells  

PubMed Central

Sterols such as cholesterol are important components of cellular membranes. They are not uniformly distributed among organelles and maintaining the proper distribution of sterols is critical for many cellular functions. Both vesicular and non-vesicular pathways move sterols between membranes and into and out of cells. There is growing evidence that a number of non-vesicular transport pathways operate in cells and, in the past few years, a number of proteins have been proposed to facilitate this transfer. Some are soluble sterol transfer proteins that may move sterol between membranes. Others are integral membranes proteins that mediate sterol efflux, uptake from cells, and perhaps intracellular sterol transfer as well. In most cases, the mechanisms and regulation of these proteins remains poorly understood. This review summarizes our current knowledge of these proteins and how they could contribute to intracellular sterol trafficking and distribution. PMID:17709145

Prinz, William A.

2007-01-01

92

Agrobacterium tumefaciens responses to plant-derived signaling molecules  

PubMed Central

As a special phytopathogen, Agrobacterium tumefaciens infects a wide range of plant hosts and causes plant tumors also known as crown galls. The complexity of Agrobacterium–plant interaction has been studied for several decades. Agrobacterium pathogenicity is largely attributed to its evolved capabilities of precise recognition and response to plant-derived chemical signals. Agrobacterium perceives plant-derived signals to activate its virulence genes, which are responsible for transferring and integrating its Transferred DNA (T-DNA) from its Tumor-inducing (Ti) plasmid into the plant nucleus. The expression of T-DNA in plant hosts leads to the production of a large amount of indole-3-acetic acid (IAA), cytokinin (CK), and opines. IAA and CK stimulate plant growth, resulting in tumor formation. Agrobacterium utilizes opines as nutrient sources as well as signals in order to activate its quorum sensing (QS) to further promote virulence and opine metabolism. Intriguingly, Agrobacterium also recognizes plant-derived signals including ?-amino butyric acid and salicylic acid (SA) to activate quorum quenching that reduces the level of QS signals, thereby avoiding the elicitation of plant defense and preserving energy. In addition, Agrobacterium hijacks plant-derived signals including SA, IAA, and ethylene to down-regulate its virulence genes located on the Ti plasmid. Moreover, certain metabolites from corn (Zea mays) also inhibit the expression of Agrobacterium virulence genes. Here we outline the responses of Agrobacterium to major plant-derived signals that impact Agrobacterium–plant interactions. PMID:25071805

Subramoni, Sujatha; Nathoo, Naeem; Klimov, Eugene; Yuan, Ze-Chun

2014-01-01

93

Sterol composition of 19 vegetable oils  

Microsoft Academic Search

The unsaponifiables from 19 vegetable oils were divided into a sterol and three other fractions by thin-layer chromatography.\\u000a All except olive and palm kernel oils gave the sterol fraction in a large quantity. Compositions of the sterol fractions were\\u000a determined by gas liquid chromatography. Identification of each sterol was carried out by gas liquid chromatography and combined\\u000a gas chromatograph-mass spectrometry.

T. Itoh; T. Tamura; T. Matsumoto

1973-01-01

94

Sterol/steroid metabolism and absorption in a generalist and specialist caterpillar: effects of dietary sterol/steroid structure, mixture and ratio.  

PubMed

Insects cannot synthesize sterols de novo, so they typically require a dietary source. Cholesterol is the dominant sterol in most insects, but because plants contain only small amounts of cholesterol, plant-feeding insects generate most of their cholesterol by metabolizing plant sterols. Plants almost always contain mixtures of different sterols, but some are not readily metabolized to cholesterol. Here we explore, in two separate experiments, how dietary phytosterols and phytosteroids, in different mixtures, ratios, and amounts, affect insect herbivore sterol/steroid metabolism and absorption; we use two caterpillars species - one a generalist (Heliothis virescens), the other a specialist (Manduca sexta). In our first experiment caterpillars were reared on two tobacco lines - one expressing a typical phystosterol profile, the other expressing high amounts/ratios of stanols and 3-ketosteroids. Caterpillars reared on the control tobacco contained mostly cholesterol, but those reared on the modified tobacco had reduced amounts of cholesterol, and lower total sterol/steroid body profiles. In our second experiment, caterpillars were reared on artificial diets containing known amounts of cholesterol, stigmasterol, cholestanol and/or cholestanone, either singly or in various combinations and ratios. Cholesterol and stigmasterol-reared moths were mostly cholesterol, while cholestanol-reared moths were mostly cholestanol. Moth tissue cholesterol concentration tended to decrease as the ratio of dietary cholestanol and/or cholestanone increased. In both moths cholestanone was metabolized into cholestanol and epicholestanol. Interestingly, M. sexta generated much more cholestanol than epicholestanol, while H. virescens did the opposite. Finally, total tissue steroid levels were significantly reduced in moths reared on diets containing very high levels of cholestanol. We discuss how dietary sterol/steroid structural differences are important with respect to sterol/steroid metabolism and uptake, including species-specific differences. PMID:23567589

Jing, Xiangfeng; Grebenok, Robert J; Behmer, Spencer T

2013-07-01

95

The mucosal immune response to plant-derived vaccines.  

PubMed

Transgenic plants present enormous potential as one of the most cost-effective and safe systems for large-scale production of proteins for industrial, pharmaceutical, veterinary and agricultural uses. Heat-stable plant-derived vaccines that are administered orally could in effect enhance vaccine coverage in children and infants, particularly in developing countries. Here we discuss the current status of plant-derived vaccines and their potential to champion the battle against infectious diseases in the least developed countries. PMID:20467887

Hefferon, Kathleen Laura

2010-10-01

96

Potential of gas chromatography-atmospheric pressure chemical ionization-time-of-flight mass spectrometry for the determination of sterols in human plasma.  

PubMed

The application of Gas Chromatography (GC)-Atmospheric Pressure Chemical Ionization (APCI)-Time-of-Flight Mass Spectrometry (TOF-MS) is presented for sterol analysis in human plasma. A commercial APCI interface was modified to ensure a well-defined humidity which is essential for controlled ionization. In the first step, optimization regarding flow rates of auxiliary gases was performed by using a mixture of model analytes. Secondly, the qualitative and quantitative analysis of sterols including oxysterols, cholesterol precursors, and plant sterols as trimethylsilyl-derivatives was successfully carried out. The characteristics of APCI together with the very good mass accuracy of TOF-MS data enable the reliable identification of relevant sterols in complex matrices. Linear calibration lines and plausible results for healthy volunteers and patients could be obtained whereas all mass signals were extracted with an extraction width of 20 ppm from the full mass data set. One advantage of high mass accuracy can be seen in the fact that from one recorded run any search for m/z can be performed. PMID:24463103

Matysik, S; Schmitz, G; Bauer, S; Kiermaier, J; Matysik, F-M

2014-04-11

97

Two-Generation Reproductive Toxicity Study of Plant Stanol Esters in Rats  

Microsoft Academic Search

Plant stanol esters are intended for use as an ingredient in food to reduce the absorption of cholesterol from the gastrointestinal tract. Consumption of plant stanol esters has a demonstrated diet-derived public health benefit, as shown by numerous clinical studies. Plant stanol esters are ring-saturated analogs of common dietary sterols that are transesterified with fatty acids from vegetable oils such

Margaret H. Whittaker; Vasilios H. Frankos; A. P. M. Wolterbeek; D. H. Waalkens-Berendsen

1999-01-01

98

Azulene Derivatives as Plant Growth Regulators  

Microsoft Academic Search

AMONG the many hundreds of compounds examined for effects in promoting cell elongation, very few having activity do not have a ring structure possessing aromatic character1. Thus it is logical to look for activity in compounds having `non-classical' aromatic rings such as derivatives of azulene and ferrocene. The azulene compounds are of particular significance since this ring system occurs frequently

Robert M. Muir

1961-01-01

99

Biosynthesis of Phytosterol Esters: Identification of a Sterol O-Acyltransferase in Arabidopsis1[OA  

PubMed Central

Fatty acyl esters of phytosterols are a major form of sterol conjugates distributed in many parts of plants. In this study we report an Arabidopsis (Arabidopsis thaliana) gene, AtSAT1 (At3g51970), which encodes for a novel sterol O-acyltransferase. When expressed in yeast (Saccharomyces cerevisiae), AtSAT1 mediated production of sterol esters enriched with lanosterol. Enzyme property assessment using cell-free lysate of yeast expressing AtSAT1 suggested the enzyme preferred cycloartenol as acyl acceptor and saturated fatty acyl-Coenyzme A as acyl donor. Taking a transgenic approach, we showed that Arabidopsis seeds overexpressing AtSAT1 accumulated fatty acyl esters of cycloartenol, accompanied by substantial decreases in ester content of campesterol and ?-sitosterol. Furthermore, fatty acid components of sterol esters from the transgenic lines were enriched with saturated and long-chain fatty acids. The enhanced AtSAT1 expression resulted in decreased level of free sterols, but the total sterol content in the transgenic seeds increased by up to 60% compared to that in wild type. We conclude that AtSAT1 mediates phytosterol ester biosynthesis, alternative to the route previously described for phospholipid:sterol acyltransferase, and provides the molecular basis for modification of phytosterol ester level in seeds. PMID:17885082

Chen, Qilin; Steinhauer, Lee; Hammerlindl, Joe; Keller, Wilf; Zou, Jitao

2007-01-01

100

The content and composition of sterols and sterol esters in sunflower and poppy seed oils  

Microsoft Academic Search

The composition and proportion of free sterols and sterol esters in crude sunflower and poppy seed oils were determined, using\\u000a preparative thin layer chromatography followed by gas chromatography with cholesterol as an internal standard. Free sterols\\u000a and sterol esters were also isolated in a liquid fraction obtained by low temperature crystallization (?80 C) of the oils\\u000a and enriched with minor

Anna Johansson

1979-01-01

101

Herbal remedies of the Maritime Indians: sterols and triterpenes of Achillea millefolium L. (Yarrow).  

PubMed

As part of ongoing studies of the medicinal aspects of Maritime flora, particularly the herbal remedies of the Micmac and Malecite Indians, the sterols and triterpenes of Achillea millefolium L. (Compositae), a widely used herbal remedy known commonly as yarrow, were determined. Using modern techniques, including nuclear magnetic resonance spectroscopy and combined GC-mass spectrometry, beta-sitosterol was identified as the major sterol and alpha-amyrin as the major triterpene of this plant. The sterols stigmasterol, campesterol, and cholesterol and the triterpenses beta-amyrin, taraxasterol, and pseudotaraxasterol were also identified. Successful therapeutic application of yarrow may be partly due to the presence of one or more of these compounds since many sterols and triterpenes exhibit a wide range of pharmacological activities. This is the first reported occurrence of cholesterol, campesterol, and the four triterpenes in yarrow. PMID:7097536

Chandler, R F; Hooper, S N; Hooper, D L; Jamieson, W D; Flinn, C G; Safe, L M

1982-06-01

102

Sterol Composition and Accumulation in Glycine max (L.) Merr Leaves under Different Filtered Sunlight Conditions 1  

PubMed Central

Soybean plants (Merr) were grown in the field in three plots. Sixteen days after sowing, two plots were covered with blue and red polyvinylchloride filters (0.45 millimeter thick) and one remained uncovered as control. Leaves of all plots were analyzed for total, free, esterified, and glycosidic sterols at two successive stages of plant growth (flowering and podripening). During the growth, total sterols increased in the control sample and under red and blue polyvinylchloride filters. Although free sterol contents were always the highest, the esterified sterols were mainly responsible for this increase. Red and blue polyvinylchloride filters caused a general decrease in the amounts of sterol classes but, during the growth, they caused the largest and most consistent changes. These filters particularly increased sitosterol and decreased stigmasterol. The changes in relative amounts of stigmasterol and sitosterol in soybean leaves might represent an interconversion between these two sterols. There seems to be a general increase-decrease relationship due to light quality. PMID:16661812

Izzo, Riccardo; Navari-Izzo, Flavia

1981-01-01

103

Molecular Mechanisms of Sterol Absorption1  

Microsoft Academic Search

Recent studies have significantly advanced our understanding of intestinal sterol absorption at the molecular level. Nuclear hormone receptors (such as liver X receptor, farnesoid X receptor and retinoid X receptor) reg- ulate the absorption of dietary sterols by modulating the transcription of several important genes involved in cho- lesterol metabolism. One of these genes encodes a mole- cule (adenosine triphosphate-binding

Hubert C. Chen

104

Sterol Composition and Ecdysteroid Content of Eggs of the Root-knot Nematodes Meloidogyne incognita and M. arenaria  

PubMed Central

Free and esterified sterols of eggs of the root-knot nematodes Meloidogyne incognita races 2 and 3 and M. arenaria race 1 were isolated and identified by gas-liquid chromatography-mass spectrometry. The major sterols of eggs of each race were 24-ethylcholesterol (33.4-38.8% of total sterol), 24-ethylcholestanol (18.3-25.3%), 24-methylcholesterol (8.6-11.7%), 24-methylcholestanol (7.7-12.5%), and cholesterol (4.6-11.6%). Consequently, the major metabolic transformation performed by Meloidogyne females or eggs upon host sterols appeared to be saturation of the sterol nucleus. The free and esterified sterols of the same race did not differ appreciably, except for a slight enrichment of the steryl esters in cholesterol. Although the sterol composition of Meloidogyne eggs differed from that of other life stages of other genera of plant-parasitic nematodes, the three Meloidogyne races could not be distinguished from each other by their egg sterols. Ecdysteroids, compounds with hormonal function in insects, were not detected by radioimmunoassay in the Meloidogyne eggs either as free ecdysteroids or as polar conjugates. PMID:19290155

Chitwood, David J.; McClure, Michael A.; Feldlaufer, Mark F.; Lusby, William R.; Oliver, Tames E.

1987-01-01

105

Sterol phylogenesis and algal evolution  

SciTech Connect

The stereochemistry of several sterol precursors and end products synthesized by two fungal-like microorganisms Prototheca wickerhamii (I) and Dictyostelium discoideum (II) have been determined by chromatographic (TLC, GLC, and HPLC) and spectral (UV, MS, and {sup 1}H NMR) methods. From I and II the following sterols were isolated from the cells: cycloartenol, cyclolaudenol, 24(28)-methylenecy-cloartanol, ergosterol, protothecasterol, 4{alpha}-methylergostanol, 4{alpha}-methylclionastanol, clionastanol, 24{beta}-ethylcholesta-8,22-enol, and dictyosterol. In addition, the mechanism of C-24 methylation was investigated in both organisms by feeding to I (2-{sup 3}H)lanosterol, (2-{sup 3}H)cycloartenol, (24{sup 3}H)lanosterol, and (methyl-{sup 2}H{sub 3})methionine and by feeding to II (methyl-{sup 2}H{sub 3})methionine. The results demonstrate that the 24{beta} configuration is formed by different alkylation routes in I and II. The authors conclude that Prototheca is an apoplastic Chlorella (i.e., an alga) and that Dictyostelium as well as the other soil amoebae that synthesize cycloartenol evolved from algal rather than fungal ancestors.

Nes, W.D.; Norton, R.A.; Crumley, F.G. (Richard B. Russell Research Center, Athens, GA (USA)); Madigan, S.J.; Katz, E.R. (State Univ. of New York at Stony Brook (USA))

1990-10-01

106

The content and composition of sterols and sterol esters in sunflower and poppy seed oils.  

PubMed

The composition and proportion of free sterols and sterol esters in crude sunflower and poppy seed oils were determined, using preparative thin layer chromatography followed by gas chromatography with cholesterol as an internal standard. Free sterols and sterols esters were also isolated in a liquid fraction obtained by low temperature crystallization (-80 C) of the oils and enriched with minor lipid classes. This enrichment procedure provided a liquid fraction suitable for studies of minor components in the oils. However, selectivity towards sterol esters was observed since sterols esterified to very long chain fatty acids (C20-C24) were preferentially retained in the precipitate. The proportion of free and esterified sterols were found to be 0.34% and 0.28%, respectively, in the sunflower oil, whereas the corresponding figures for poppy seed oil were 0.33% and 0.05%. Sunflower oil was characterized by a relatively high percentage of delta 7-sterols, preferentially obtained in the esterified fraction, and by very long chain saturated fatty acids of sterol esters. The sterols in poppy seed oil were composed almost entirely of campesterol, stigmasterol, sitosterol and delta 5-avenasterol, although their percentage distributions were remarkably different in the free and esterified fraction. PMID:449631

Johansson, A

1979-03-01

107

Plant-derived virus-like particles as vaccines  

PubMed Central

Virus-like particles (VLPs) are self-assembled structures derived from viral antigens that mimic the native architecture of viruses but lack the viral genome. VLPs have emerged as a premier vaccine platform due to their advantages in safety, immunogenicity, and manufacturing. The particulate nature and high-density presentation of viral structure proteins on their surface also render VLPs as attractive carriers for displaying foreign epitopes. Consequently, several VLP-based vaccines have been licensed for human use and achieved significant clinical and economical success. The major challenge, however, is to develop novel production platforms that can deliver VLP-based vaccines while significantly reducing production times and costs. Therefore, this review focuses on the essential role of plants as a novel, speedy and economical production platform for VLP-based vaccines. The advantages of plant expression systems are discussed in light of their distinctive posttranslational modifications, cost-effectiveness, production speed, and scalability. Recent achievements in the expression and assembly of VLPs and their chimeric derivatives in plant systems as well as their immunogenicity in animal models are presented. Results of human clinical trials demonstrating the safety and efficacy of plant-derived VLPs are also detailed. Moreover, the promising implications of the recent creation of “humanized” glycosylation plant lines as well as the very recent approval of the first plant-made biologics by the U. S. Food and Drug Administration (FDA) for plant production and commercialization of VLP-based vaccines are discussed. It is speculated that the combined potential of plant expression systems and VLP technology will lead to the emergence of successful vaccines and novel applications of VLPs in the near future. PMID:22995837

Chen, Qiang; Lai, Huafang

2013-01-01

108

Sterols in spermatogenesis and sperm maturation  

PubMed Central

Mammalian spermatogenesis is a complex developmental program in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. One intriguing aspect of sperm production is the dynamic change in membrane lipid composition that occurs throughout spermatogenesis. Cholesterol content, as well as its intermediates, differs vastly between the male reproductive system and nongonadal tissues. Accumulation of cholesterol precursors such as testis meiosis-activating sterol and desmosterol is observed in testes and spermatozoa from several mammalian species. Moreover, cholesterogenic genes, especially meiosis-activating sterol-producing enzyme cytochrome P450 lanosterol 14?-demethylase, display stage-specific expression patterns during spermatogenesis. Discrepancies in gene expression patterns suggest a complex temporal and cell-type specific regulation of sterol compounds during spermatogenesis, which also involves dynamic interactions between germ and Sertoli cells. The functional importance of sterol compounds in sperm production is further supported by the modulation of sterol composition in spermatozoal membranes during epididymal transit and in the female reproductive tract, which is a prerequisite for successful fertilization. However, the exact role of sterols in male reproduction is unknown. This review discusses sterol dynamics in sperm maturation and describes recent methodological advances that will help to illuminate the complexity of sperm formation and function. PMID:23093550

Keber, Rok; Rozman, Damjana; Horvat, Simon

2013-01-01

109

Plant amino acid-derived vitamins: biosynthesis and function.  

PubMed

Vitamins are essential organic compounds for humans, having lost the ability to de novo synthesize them. Hence, they represent dietary requirements, which are covered by plants as the main dietary source of most vitamins (through food or livestock's feed). Most vitamins synthesized by plants present amino acids as precursors (B1, B2, B3, B5, B7, B9 and E) and are therefore linked to plant nitrogen metabolism. Amino acids play different roles in their biosynthesis and metabolism, either incorporated into the backbone of the vitamin or as amino, sulfur or one-carbon group donors. There is a high natural variation in vitamin contents in crops and its exploitation through breeding, metabolic engineering and agronomic practices can enhance their nutritional quality. While the underlying biochemical roles of vitamins as cosubstrates or cofactors are usually common for most eukaryotes, the impact of vitamins B and E in metabolism and physiology can be quite different on plants and animals. Here, we first aim at giving an overview of the biosynthesis of amino acid-derived vitamins in plants, with a particular focus on how this knowledge can be exploited to increase vitamin contents in crops. Second, we will focus on the functions of these vitamins in both plants and animals (and humans in particular), to unravel common and specific roles for vitamins in evolutionary distant organisms, in which these amino acid-derived vitamins play, however, an essential role. PMID:24368523

Miret, Javier A; Munné-Bosch, Sergi

2014-04-01

110

Plant-derived pharmaceuticals for the developing world.  

PubMed

Plant-produced vaccines and therapeutic agents offer enormous potential for providing relief to developing countries by reducing the incidence of infant mortality caused by infectious diseases. Vaccines derived from plants have been demonstrated to effectively elicit an immune response. Biopharmaceuticals produced in plants are inexpensive to produce, require fewer expensive purification steps, and can be stored at ambient temperatures for prolonged periods of time. As a result, plant-produced biopharmaceuticals have the potential to be more accessible to the rural poor. This review describes current progress with respect to plant-produced biopharmaceuticals, with a particular emphasis on those that target developing countries. Specific emphasis is given to recent research on the production of plant-produced vaccines toward human immunodeficiency virus, malaria, tuberculosis, hepatitis B virus, Ebola virus, human papillomavirus, rabies virus and common diarrheal diseases. Production platforms used to express vaccines in plants, including nuclear and chloroplast transformation, and the use of viral expression vectors, are described in this review. The review concludes by outlining the next steps for plant-produced vaccines to achieve their goal of providing safe, efficacious and inexpensive vaccines to the developing world. PMID:23857915

Hefferon, Kathleen

2013-10-01

111

Comparative safety assessment of plant-derived foods.  

PubMed

The second generation of genetically modified (GM) plants that are moving towards the market are characterized by modifications that may be more complex and traits that more often are to the benefit of the consumer. These developments will have implications for the safety assessment of the resulting plant products. In part of the cases the same crop plant can, however, also be obtained by 'conventional' breeding strategies. The breeder will decide on a case-by-case basis what will be the best strategy to reach the set target and whether genetic modification will form part of this strategy. This article discusses important aspects of the safety assessment of complex products derived from newly bred plant varieties obtained by different breeding strategies. On the basis of this overview, we conclude that the current process of the safety evaluation of GM versus conventionally bred plants is not well balanced. GM varieties are elaborately assessed, yet at the same time other crop plants resulting from conventional breeding strategies may warrant further food safety assessment for the benefit of the consumer. We propose to develop a general screening frame for all newly developed plant varieties to select varieties that cannot, on the basis of scientific criteria, be considered as safe as plant varieties that are already on the market. PMID:17983697

Kok, E J; Keijer, J; Kleter, G A; Kuiper, H A

2008-02-01

112

Sterol content in sunflower seeds ( Helianthus annuus L.) as affected by genotypes and environmental conditions  

Microsoft Academic Search

Phytosterols play essential roles in many plant cell mechanisms. They are of industrial interest since, as part of the diet, they can reduce low density lipoprotein cholesterol. An increase in plant sterol contents, by improved crop varieties or crop management, could help to answer industrial demands and also to develop environmentally friendly extraction methods. The aim of this study was

Jane Roche; Marion Alignan; Andrée Bouniols; Muriel Cerny; Zephirin Mouloungui; Félicity Vear; Othmane Merah

2010-01-01

113

Diet micronutrient balance matters: How the ratio of dietary sterols/steroids affects development, growth and reproduction in two lepidopteran insects.  

PubMed

Insects lack the ability to synthesize sterols de novo so they acquire this essential nutrient from their food. Cholesterol is the dominant sterol found in most insects, but in plant vegetative tissue it makes up only a small fraction of the total sterol profile. Instead, plants mostly contain phytosterols; plant-feeding insects generate the majority of their cholesterol by metabolizing phytosterols. However, not all phytosterols are readily converted to cholesterol, and some are even deleterious when ingested above a threshold level. In a recent study we showed that caterpillars reared on tobacco accumulating novel sterols/steroids exhibited reduced performance, even when suitable sterols were present. In the current study we examined how the dominant sterols (cholesterol and stigmasterol) and steroids (cholestanol and cholestanone) typical of the modified tobacco plants affected two insect herbivores (Heliothis virescens and Helicoverpa zea). The sterols/steroids were incorporated into synthetic diets singly, as well as in various combinations, ratios and amounts. For each insect species, a range of performance values was recorded for two generations, with the eggs from the 1st-generation adults as the source of neonates for the 2nd-generation. Performance on the novel steroids (cholestanol and cholestanone) was extremely poor compared to suitable sterols (cholesterol and stigmasterol). Additionally, performance tended to decrease as the ratio of the novel dietary steroids increased. We discuss how the balance of different dietary sterols/steroids affected our two caterpillar species, relate this back to recent studies on sterol/steroid metabolism in these two species, and consider the potential application of sterol/steroid modification in crops. PMID:24953330

Jing, Xiangfeng; Grebenok, Robert J; Behmer, Spencer T

2014-08-01

114

Response of ?? T cells to plant-derived tannins  

PubMed Central

Many pharmaceutical drugs are isolated from plants used in traditional medicines. Through screening plant extracts, both traditional medicines and compound libraries, new pharmaceutical drugs continue to be identified. Currently, two plant-derived agonists for ?? T cells are described. These plant-derived agonists impart innate effector functions upon distinct ?? T cell subsets. Plant tannins represent one class of ?? T cell agonist and preferentially activate the mucosal population. Mucosal ?? T cells function to modulate tissue immune responses and induce epithelium repair. Select tannins, isolated from apple peel, rapidly induce immune gene transcription in ?? T cells, leading to cytokine production and increased responsiveness to secondary signals. Activity of these tannin preparations tracks to the procyanidin fraction, with the procyanidin trimer (C1) having the most robust activity defined to date. The response to the procyanidins is evolutionarily conserved in that responses are seen with human, bovine, and murine ?? T cells. Procyanidin-induced responses described in this review likely account for the expansion of mucosal ?? T cells seen in mice and rats fed soluble extracts of tannins. Procyanidins may represent a novel approach for treatment of tissue damage, chronic infection, and autoimmune therpies. PMID:19166386

Holderness, Jeff; Hedges, Jodi F.; Daughenbaugh, Katie; Kimmel, Emily; Graff, Jill; Freedman, Brett; Jutila, Mark A.

2008-01-01

115

Low doses of eicosapentaenoic acid and docosahexaenoic acid from fish oil dose-dependently decrease serum triglyceride concentrations in the presence of plant sterols in hypercholesterolemic men and women.  

PubMed

Plant sterols (PSs) lower LDL cholesterol (LDL-C) concentrations, whereas the n-3 (?-3) fish fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) lower triglyceride (TG) concentrations. Incorporating both PSs and EPA+DHA from fish oil (FO) in a single food format was expected to beneficially affect 2 blood lipid risk factors. The aim of this study was to investigate the dose-response relation between low doses (<2 g/d) of EPA+DHA from FO, incorporated in a low-fat PS-enriched spread, and TG concentrations. In addition, effects on LDL-C were investigated. The study was designed as a randomized, double-blind, placebo-controlled parallel study. After a 4-wk run-in period, subjects were randomly assigned to consume either a control (C) spread (no PSs, no FO) or 1 of 4 intervention spreads containing a fixed amount of PSs (2.5 g/d) and varying amounts of FO (0.0, 0.9, 1.3, and 1.8 g/d of EPA+DHA) for 4 wk. Before and after the intervention, fasting blood samples were drawn for measuring serum lipids and EPA and DHA in erythrocyte membranes. In total, 85 hypercholesterolemic men and 247 women with a mean age of 57.9 y (range: 25-74 y) were included. Eighteen subjects dropped out during the study. At baseline, mean TG and LDL-C concentrations were 1.09 and 4.00 mmol/L, respectively. After the intervention, a significant dose-response relation for the TG-lowering effect of EPA+DHA [?ln (TG) = -0.07 mmol/L per gram of EPA+DHA; P < 0.01] was found. Compared with the C group, TG concentrations were 9.3-16.2% lower in the different FO groups (P < 0.05 for all groups). LDL-C concentrations were 11.5-14.7% lower in the different PS groups than in the C group (P < 0.01 for all groups). EPA and DHA in erythrocyte membranes were dose-dependently higher after FO intake than after the C spread, indicating good compliance. Consumption of a low-fat spread enriched with PSs and different low doses of n-3 fatty acids from FO decreased TG concentrations in a dose-dependent manner and decreased LDL-C concentrations. This trial was registered at clinicaltrials.gov as NCT01313988. PMID:25122648

Ras, Rouyanne T; Demonty, Isabelle; Zebregs, Yvonne E M P; Quadt, Johan F A; Olsson, Johan; Trautwein, Elke A

2014-10-01

116

Cameroonian Medicinal Plants: Pharmacology and Derived Natural Products  

PubMed Central

Many developing countries including Cameroon have mortality patterns that reflect high levels of infectious diseases and the risk of death during pregnancy and childbirth, in addition to cancers, cardiovascular diseases and chronic respiratory diseases that account for most deaths in the developed world. Several medicinal plants are used traditionally for their treatment. In this review, plants used in Cameroonian traditional medicine with evidence for the activities of their crude extracts and/or derived products have been discussed. A considerable number of plant extracts and isolated compounds possess significant antimicrobial, anti-parasitic including antimalarial, anti-proliferative, anti-inflammatory, anti-diabetes, and antioxidant effects. Most of the biologically active compounds belong to terpenoids, phenolics, and alkaloids. Terpenoids from Cameroonian plants showed best activities as anti-parasitic, but rather poor antimicrobial effects. The best antimicrobial, anti-proliferative, and antioxidant compounds were phenolics. In conclusion, many medicinal plants traditionally used in Cameroon to treat various ailments displayed good activities in vitro. This explains the endeavor of Cameroonian research institutes in drug discovery from indigenous medicinal plants. However, much work is still to be done to standardize methodologies and to study the mechanisms of action of isolated natural products. PMID:21833168

Kuete, Victor; Efferth, Thomas

2010-01-01

117

Approaches to the Analysis of Plant-Derived Natural Products  

Microsoft Academic Search

The term “plant-derived natural product” is extremely broad and the scope of this chapter is determined by the nature of lower-abundance\\u000a secondary metabolites rather than storage proteins, starch, cell walls, and lipids. In some instances, however, similar techniques\\u000a can used to measure both groups of compounds. The bioactivity of secondary metabolites underlines their importance in human\\u000a nutrition, health, pharmacy and

Lionel Hill; Trevor L. Wang

118

Metabolic engineering of sugars and simple sugar derivatives in plants.  

PubMed

Carbon captured through photosynthesis is transported, and sometimes stored in plants, as sugar. All organic compounds in plants trace to carbon from sugars, so sugar metabolism is highly regulated and integrated with development. Sugars stored by plants are important to humans as foods and as renewable feedstocks for industrial conversion to biofuels and biomaterials. For some purposes, sugars have advantages over polymers including starches, cellulose or storage lipids. This review considers progress and prospects in plant metabolic engineering for increased yield of endogenous sugars and for direct production of higher-value sugars and simple sugar derivatives. Opportunities are examined for enhancing export of sugars from leaves. Focus then turns to manipulation of sugar metabolism in sugar-storing sink organs such as fruits, sugarcane culms and sugarbeet tubers. Results from manipulation of suspected 'limiting' enzymes indicate a need for clearer understanding of flux control mechanisms, to achieve enhanced levels of endogenous sugars in crops that are highly selected for this trait. Outcomes from in planta conversion to novel sugars and derivatives range from severe interference with plant development to field demonstration of crops accumulating higher-value sugars at high yields. The differences depend on underlying biological factors including the effects of the novel products on endogenous metabolism, and on biotechnological fine-tuning including developmental expression and compartmentation patterns. Ultimately, osmotic activity may limit the accumulation of sugars to yields below those achievable using polymers; but results indicate the potential for increases above current commercial sugar yields, through metabolic engineering underpinned by improved understanding of plant sugar metabolism. PMID:23043616

Patrick, John W; Botha, Frikkie C; Birch, Robert G

2013-02-01

119

Gas chromatographic analysis of plant sterols  

Technology Transfer Automated Retrieval System (TEKTRAN)

Phytosterols are well-known for their ability to lower blood cholesterol by competing with absorption of cholesterol from the diet and reabsorption of bile cholesterol. Phytosterols as food ingredients are “Generally Recognized As Safe” (GRAS) by the FDA, and they are increasingly incorporated into ...

120

Characterization, mutagenesis and mechanistic analysis of an ancient algal sterol C24-methyltransferase: Implications for understanding sterol evolution in the green lineage.  

PubMed

Sterol C24-methyltransferases (SMTs) constitute a group of sequence-related proteins that catalyze the pattern of sterol diversity across eukaryotic kingdoms. The only gene for sterol alkylation in green algae was identified and the corresponding catalyst from Chlamydomonas reinhardtii (Cr) was characterized kinetically and for product distributions. The properties of CrSMT were similar to those predicted for an ancient SMT expected to possess broad C3-anchoring requirements for substrate binding and formation of 24?-methyl/ethyl ?(25(27))-olefin products typical of primitive organisms. Unnatural ?(24(25))-sterol substrates, missing a C4?-angular methyl group involved with binding orientation, convert to product ratios in favor of ?(24(28))-products. Remodeling the active site to alter the electronics of Try110 (to Leu) results in delayed timing of the hydride migration from methyl attack of the ?(24)-bond, that thereby produces metabolic switching of product ratios in favor of ?(25(27))-olefins or impairs the second C1-transfer activity. Incubation of [27-(13)C]lanosterol or [methyl-(2)H3]SAM as co-substrates established the CrSMT catalyzes a sterol methylation pathway by the "algal" ?(25(27))-olefin route, where methylation proceeds by a conserved SN2 reaction and de-protonation proceeds from the pro-Z methyl group on lanosterol corresponding to C27. This previously unrecognized catalytic competence for an enzyme of sterol biosynthesis, together with phylogenomic analyses, suggest that mutational divergence of a promiscuous SMT produced substrate- and phyla-specific SMT1 (catalyzes first biomethylation) and SMT2 (catalyzes second biomethylation) isoforms in red and green algae, respectively, and in the case of SMT2 selection afforded modification in reaction channeling necessary for the switch in ergosterol (24?-methyl) biosynthesis to stigmasterol (24?-ethyl) biosynthesis during the course of land plant evolution. PMID:25132279

Haubrich, Brad A; Collins, Emily K; Howard, Alicia L; Wang, Qian; Snell, William J; Miller, Matthew B; Thomas, Crista D; Pleasant, Stephanie K; Nes, W David

2014-08-14

121

Tracking plant-derived biomarkers from source to sink in the Miners River, Upper Peninsula of Michigan (USA)  

NASA Astrophysics Data System (ADS)

Biogeochemical cycling of terrestrial organic matter and it subsequent burial plays a vital role in the global carbon cycle. Rivers provide a pathway for terrestrial organic carbon dispersal and integration into sediments. Terrestrial plant biomarkers are useful tools for studying carbon cycling because they can provide an indication of the source of organic carbon in both modern and ancient sediments. Biomarkers can also be used as paleovegetation proxies in geologic sediments where fossils are absent. However, limited information is available about the dispersal and deposition of plant biomarkers in modern river systems, especially for compounds that provide taxonomic specificity such as di- and triterpenoids (diagnostic for conifers and angiosperms, respectively). To better resolve the modes of biomarker transport within fluvial and riparian systems, we characterized plant biomarker transport in the Miners River, a small river basin within a mixed angiosperm-conifer forest at Pictured Rocks National Lakeshore (MI, USA). To assess the transport of biomarkers in river systems, we collected plants, soils, river sediments, and filtered particulate and dissolved organic carbon from seven sites from the headwaters to Lake Superior along the Miners River (~20 km pathway). All samples contained long-chain n-alkyl lipids, sterols, diterpenoids (abietane and pimarane classes), and triterpenoids (oleanane, ursane, and lupane classes). With the exception of a soil sample taken at a depth of 30 cm, triterpenoids are found in higher concentrations than diterpenoids in riparian soils and river sediments. Biomarker compositions in riparian soils, point bar, and overbank deposits are similar to the surrounding vegetation, albeit much lower in concentration. The composition of di- and triterpenoids in the river-suspended particulate organic carbon is similar in composition to the surrounding vegetation and soils. We developed a method to isolate biomarkers in the dissolved organic carbon fraction in river waters using solid-phase extraction and the preliminary data suggests that di- and triterpenoids are transported as dissolved organic carbon, however concentrations are lower than in the particulate organic carbon fraction. Results from the Miners River will help to better define terrestrial organic matter cycling in small river catchments. Characterizing how plant biomarkers are transported in river systems will enhance our interpretations of plant biomarkers in the geologic record. This will provide new insights into biomarker transport and potential source/sink biases in fluvial systems and thus identify potential complications for using plant-derived biomarkers as quantitative paleovegetation indicators and will enhance the use of biomarker-specific isotope analyses.

Giri, S. J.; Diefendorf, A. F.; Lowell, T. V.

2012-12-01

122

Effects of sterols on the development and aging of caenorhabditis elegans  

Technology Transfer Automated Retrieval System (TEKTRAN)

Because Caenorhabditis elegans lacks several components of the de novo sterol biosynthesis pathway, it requires sterols as essential nutrients. Supplemented cholesterol undergoes extensive enzymatic modification in C. elegans to form other sterols of unknown function. Because sterol metabolism in ...

123

Identification of ergosterol and inhibition of sterol synthesis by. Delta. sup 5 -sterols in GL7, an auxotrophic mutant of yeast  

SciTech Connect

Synthesis of ergosterol was demonstrated in the GL7 mutant of Saccharomyces cerevisiae. This sterol auxotroph has been thought to lack the ability to synthesize sterols due both to the absence of 2,3-oxidosqualene cyclase and to a heme deficiency eliminating cytochrome P-450 which is required in demethylation at C-14. However, when the exogenous sterol was 5{alpha}-cholestan-3{beta}-ol, 5{alpha}-cholest-8(14)-en-3{beta}-ol, or 24{beta}-methyl-5{alpha}-cholest-8(14)-en-3{beta}-ol, sterol synthesis was found to proceed yielding 1-3 fg/cell of ergosterol. Ergosterol was identified by mass spectroscopy, gas and high performance liquid chromatography, ultraviolet spectroscopy, and radioactive labelling from ({sup 3}H)acetate. Except for some cholest-5-en-3{beta}-ol (cholesterol) which was derived from the 5{alpha}-cholestan-3{beta}-ol, the stanol and the two 8(14)-stenols were not significantly metabolized confirming the absence of an isomerase for migration of the double bond from C-8(14) to C-7. Drastic reduction of ergosterol synthesis to not more than 0.06 fg/cell was observed when the exogenous sterol either had a double bond at C-5, as in the case of cholesterol, or could be metabolized to a sterol with such a bond. Thus, both 5{alpha}-cholest-8(9)-en-3{beta}-ol and 5{alpha}-cholest-7-en-3{beta}-ol (lathosterol) were converted to cholesta-5,7-dien-3{beta}-ol (7-dehydrocholesterol), and the presence of the latter dienol depressed the level of ergosterol.

Dhanuka, I.C.

1988-01-01

124

4-Hydroxyisoleucine: a plant-derived treatment for metabolic syndrome.  

PubMed

The plant fenugreek has been used for centuries as a treatment for diabetes. This article presents evidence that the major isomer of 4-hydroxyisoleucine, an atypical branched-chain amino acid derived from fenugreek, is responsible for the effects of this plant on glucose and lipid metabolism. 4-Hydroxyisoleucine was demonstrated to stimulate glucose-dependent insulin secretion by a direct effect on pancreatic islets. In addition to stimulating insulin secretion, 4-hydroxyisoleucine reduced insulin resistance in muscle and/or liver by activating insulin receptor substrate-associated phosphoinositide 3 (PI3) kinase activity. 4-Hydroxyisoleucine also reduced body weight in diet-induced obese mice. The decrease in body weight was associated with a marked decrease in both plasma insulin and glucose levels, both of which are elevated in this animal model. Finally, 4-hydroxyisoleucine decreased elevated plasma triglyceride and total cholesterol levels in a hamster model of diabetes. Based on the beneficial metabolic properties that have been demonstrated, 4-hydroxyisoleucine, a simple, plant-derived amino acid, may represent an attractive new candidate for the treatment of type 2 diabetes, obesity and dyslipidemia, all key components of metabolic syndrome. PMID:19337956

Jetté, Lucie; Harvey, Laurent; Eugeni, Karen; Levens, Nigel

2009-04-01

125

Herbal remedies of the Maritime indians: sterols and triterpenes of Tanacetum vulgare L. (Tansy).  

PubMed

Plant sterols and triterpenes exhibit a wide range of pharmacological activities. As part of our ongoing studies of the medicinal aspects of Maritime flora, particularly the herbal remedies of the Micmac and Malecite Indians, we determined the nature of the sterols and triterpenes of Tanacetum vulgare L. (Compositae)-a widely used herbal remedy usually referred to as tansy. By using thin layer and gas chromatographics, nuclear magnetic resonance (NMR) spectroscopy and combined gas chromatography-mass spectrometry, we were able to identify beta-sitosterol as the major sterol and alpha-amyrin as the major triterpene of tansy. We also identified the sterols stigmasterol, campesterol and cholesterol, and the triterpenes beta-amyrin and taraxasterol. A fourth triterpene was tentatively identified as pseudo-taraxasterol. The successful therapeutic application of this herb may be due partly to the presence of one or more of these compounds. The sterols and triterpenes of tansy have not been previously reported; neither, to our knowledge, have the NMR spectra of the amyrins and the NMR and mass spectra of taraxasterol. PMID:7087682

Chandler, R F; Hooper, S N; Hooper, D L; Jamieson, W D; Lewis, E

1982-02-01

126

Plant derived alternatives for hormone replacement therapy (HRT).  

PubMed

Abstract Hormone replacement therapy (HRT) has undisputable positive effects on climacteric complaints, in the bone and on body weight but also several undesired side effects. Therefore, plant-derived alternatives are currently promoted. Phytoestrogens - primarily the isoflavones genistein, daidzein and coumestrol, stemming from soy (Glycine max) or red clover (Trifolium pratense) - were suggested to have the desired but not the undesired effects of estrogens. Most recently published placebo-controlled studies question the beneficial effects. When taken at the time of puberty however, phytoestrogens appear to protect against mammary cancer later in life. Extracts from the rhizome of Cimicifuga racemosa (black cohosh) have no estrogenic effects. In a narrow dose range they have beneficial effects on climacteric complaints, which are due to several compounds with dopaminergic, noradrenergic, serotoninergic and GABAergic actions that act together in the hypothalamus. Ecdysone is produced by several plants, including spinach (Spinacia oleracea) and was very early on shown to increase muscle mass. Later it became apparent that spinach extracts containing ecdysone decreased body fat load, thereby reducing secretion of proinflammatory cytokines by visceral adipocytes and oxidative stress. This had beneficial effects on body weight and serum lipids not only in obese postmenopausal but also in premenopausal women and in men. For the above-described plant extracts, solid placebo-controlled clinical trials are available. For other plant extracts claiming beneficial effects on climacteric complaints or postmenopausal diseases, no solid data are available. PMID:25436745

Seidlova-Wuttke, Dana; Jarry, Hubertus; Wuttke, Wolfgang

2013-12-01

127

Assessing anthropogenic contamination in surface sediments of Niger Delta, Nigeria with fecal sterols and n-alkanes as indicators.  

PubMed

The occurrence of sterols and n-alkanes in surface sediments from rivers and canals in the Niger Delta, Nigeria, determined with a gas chromatography-mass spectrometry method, was used to assess the impacts of anthropogenic activities in the area. The concentrations of total sterols (??Sterol) and n-alkanes (???n-alkane) in the sediments ranged from 133 to 2040 ng/g and 474 to 79,200 ng/g, respectively. An evaluation of the source diagnostic indices indicated that petroleum related sources (petrogenic) were the main contributor of n-alkanes in the samples, with minor contribution from higher plants waxes (biogenic), while the sterols were mainly of biogenic origin. The ratio of ?-cholestanone/(?-cholestanone+?-cholestanone), a commonly used source diagnostic index, implicated no fecal contamination in most of the sediment samples under investigation. These results have established the occurrence of anthropogenic contamination in Niger Delta sediments with significant contributions from petrogenic sources. PMID:23137973

Sojinu, Samuel O; Sonibare, Oluwadayo O; Ekundayo, O; Zeng, Eddy Y

2012-12-15

128

[The demonstration of a methodology for identifying and analysing oxygenated sterols present in radicular cysts].  

PubMed

Our work has two main aims: to identify oxygenated sterols that accompany cholesterol in dental cyst and to develop effective methods for "profile" analyses of these sterols. Attention as focused on a family of products derived from cholesterol, characterized by the presence of one or more oxygenated functions. More than fifty of these oxysterols are known and find most of time in different parts of the body. In the procedure, lipids are isolated from dental cyst, the fraction is trimethylsilylated and analysed by capillary gas chromatography. Sterols are identified by comparison with reference compounds. However, two sterols of particular interest, viz cholesterol alpha and beta epoxides, are so easily produced from cholesterol (even when rigorous precautions are taken) that indirect methods of analysis are strongly advisable. An adequate degree of quantification is possible for sterols such as 26-hydroxycholesterol (26OHCL), which do not arise significantly as artefacts. Even to verify the fraction which seems to be 26OHCL we used thin layer chromatography coupled with mass spectrometer. PMID:8219691

Sicard-Bons, C; Bons, P; Escola, R

1993-01-01

129

How sterol tilt regulates properties and organization of lipid membranes and membrane insertions  

PubMed Central

Serving as a crucial component of mammalian cells, cholesterol critically regulates the functions of biomembranes. This review focuses on a specific property of cholesterol and other sterols: the tilt modulus ? that quantifies the energetic cost of tilting sterol molecules inside the lipid membrane. We show how ? is involved in determining properties of cholesterol-containing membranes, and detail a novel approach to quantify its value from atomistic molecular dynamics (MD) simulations. Specifically, we link ? with other structural, thermodynamic, and mechanical properties of cholesterol-containing lipid membranes, and delineate how this useful parameter can be obtained from the sterol tilt probability distributions derived from relatively small-scale unbiased MD simulations. We demonstrate how the tilt modulus quantitatively describes the aligning field that sterol molecules create inside the phospholipid bilayers, and we relate ? to the bending rigidity of the lipid bilayer through effective tilt and splay energy contributions to the elastic deformations. Moreover, we show how ? can conveniently characterize the “condensing effect” of cholesterol on phospholipids. Finally, we demonstrate the importance of this cholesterol aligning field to the proper folding and interactions of membrane peptides. Given the relative ease of obtaining the tilt modulus from atomistic simulations, we propose that ? can be routinely used to characterize the mechanical properties of sterol/lipid bilayers, and can also serve as a required fitting parameter in multi-scaled simulations of lipid membrane models to relate the different levels of coarse-grained details. PMID:23291283

Khelashvili, George; Harries, Daniel

2013-01-01

130

Pentacyclic hemiacetal sterol with antifouling and cytotoxic activities from the soft coral Nephthea sp.  

PubMed

A novel unusual pentacyclic hemiacetal sterol nephthoacetal (1), was isolated from soft coral Nephthea sp. The structure of this sterol was inferred from its two acetyl derivatives (2) and (3), by means of spectroscopic methods, and quantum chemical calculations. Anti-fouling activity of compounds 1-3 against Bugula neritina larvae was evaluated, sterol (1) exhibited significant inhibitory effect with EC(50) value of 2.5 ?g/mL, while having low toxicity with LC(50)>25.0 ?g/mL. The in vitro cytotoxic activity of compounds 1-3 against HeLa cells was also evaluated, all of them exhibited moderate cytotoxicity with IC(50) values of 12.3 (1), 10.1 (2), and 19.6 ?g/mL (3), respectively. PMID:23294699

Zhang, Jun; Li, Liang-Chun; Wang, Kai-Ling; Liao, Xiao-Jian; Deng, Zhou; Xu, Shi-Hai

2013-02-15

131

The biological activity of a-mangostin, a larvicidal botanic mosquito sterol carrier protein-2 inhibitor  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alpha-mangostin derived from mangosteen was identified as a mosquito sterol carrier protein-2 inhibitor via high throughput insecticide screening. Alpha-mangostin was tested for its larvicidal activity against 3rd instar larvae of six mosquito species and the LC50 values range from 0.84 to 2.90 ppm....

132

Universal Behavior of Membranes with Sterols  

PubMed Central

Lanosterol is the biosynthetic precursor of cholesterol and ergosterol, sterols that predominate in the membranes of mammals and lower eukaryotes, respectively. These three sterols are structurally quite similar, yet their relative effects on membranes have been shown to differ. Here we study the effects of cholesterol, lanosterol, and ergosterol on 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine lipid bilayers at room temperature. Micropipette aspiration is used to determine membrane material properties (area compressibility modulus), and information about lipid chain order (first moments) is obtained from deuterium nuclear magnetic resonance. We compare these results, along with data for membrane-bending rigidity, to explore the relationship between membrane hydrophobic thickness and elastic properties. Together, such diverse approaches demonstrate that membrane properties are affected to different degrees by these structurally distinct sterols, yet nonetheless exhibit universal behavior. PMID:16326903

Henriksen, J.; Rowat, A. C.; Brief, E.; Hsueh, Y. W.; Thewalt, J. L.; Zuckermann, M. J.; Ipsen, J. H.

2006-01-01

133

Ecological significance of sterols in aquatic food webs  

Microsoft Academic Search

\\u000a Sterols are indispensable for a multitude of physiological processes in all eukaryotic organisms. In most eukaryotes, sterols\\u000a are synthesized de novo from low molecular weight precursors. Some invertebrates (e.g., all arthropods examined to date),\\u000a however, are incapable of synthesizing sterols de novo, and therefore have to acquire sterols from their diet. Here, we aim\\u000a to demonstrate that such nutritional requirements

Dominik Martin-Creuzburg; Eric von Elert

134

Plant-Derived Human Collagen Scaffolds for Skin Tissue Engineering  

PubMed Central

Tissue engineering scaffolds are commonly formed using proteins extracted from animal tissues, such as bovine hide. Risks associated with the use of these materials include hypersensitivity and pathogenic contamination. Human-derived proteins lower the risk of hypersensitivity, but possess the risk of disease transmission. Methods engineering recombinant human proteins using plant material provide an alternate source of these materials without the risk of disease transmission or concerns regarding variability. To investigate the utility of plant-derived human collagen (PDHC) in the development of engineered skin (ES), PDHC and bovine hide collagen were formed into tissue engineering scaffolds using electrospinning or freeze-drying. Both raw materials were easily formed into two common scaffold types, electrospun nonwoven scaffolds and lyophilized sponges, with similar architectures. The processing time, however, was significantly lower with PDHC. PDHC scaffolds supported primary human cell attachment and proliferation at an equivalent or higher level than the bovine material. Interleukin-1 beta production was significantly lower when activated THP-1 macrophages where exposed to PDHC electrospun scaffolds compared to bovine collagen. Both materials promoted proper maturation and differentiation of ES. These data suggest that PDHC may provide a novel source of raw material for tissue engineering with low risk of allergic response or disease transmission. PMID:23298216

Willard, James J.; Drexler, Jason W.; Das, Amitava; Roy, Sashwati; Shilo, Shani; Shoseyov, Oded

2013-01-01

135

Some important aspects of sterol analysis of vegetable oils  

Microsoft Academic Search

The content and composition of the sterol fraction is an important indicator of the value of vegetable oils, mainly due to the cholesterol-lowering effect of certain sterol compounds. Although many methods have been described in the literature, various steps may still cause errors during sample preparation. The present article covers some of the key steps in sterol analysis that are

Erkki Mäeorga; Peeter Läänistea; Juhan Jőudua; Uno Mäeorgb

136

Biological removal of phyto-sterols in pulp mill effluents.  

PubMed

Phyto-sterols and extractives found in pulp mill effluents are suspected to cause endocrine abnormalities in receiving water fish. The control of sterols in pulp mill effluents through biological secondary wastewater treatment was studied using two lab-scale bioreactor systems. After achieving a stable performance, both bioreactor systems successfully removed (>90%) sterols and the estimated biodegradation was up to 80%. Reactor 1 system operating at 6.7 ± 0.2 pH effectively treated pulp mill effluent sterols spiked up to 4500 ?g/L in 11 h HRT and 11 day SRT. However, Reactor 2 system operating at 7.6 ± 0.2 pH performed relatively poorly. Retention time reductions beyond critical values deteriorated the performance of treatment systems and quickly reduced the sterols biodegradation. The biodegradation loss was indicated by mixed liquor sterols content that started increasing. This biodegradation loss was compensated by the increased role of bio-adsorption and the overall sterols removal remained relatively high. Hence, a relatively small (20-30%) loss in the overall sterols removal efficiency did not fully reflect the associated major (60-70%) loss in the sterols biodegradation because the amount of sterols accumulated in the sludge due to adsorption increased so the estimate of sterols removal through adsorption increased from 30-40% to 70-80% keeping the overall sterols removal still high. PMID:24211569

Mahmood-Khan, Zahid; Hall, Eric R

2013-12-15

137

Serum sterol profiling reveals increased cholesterol biosynthesis in childhood obesity.  

PubMed

Quantitative sterol profiling in obese children and their clinical implications have not been fully investigated. The aim of study was to evaluate the metabolic changes in serum cholesterol and its precursors and metabolites, and their associations with clinical characteristics of childhood obesity. A total of 253 children aged 6-14 years (72 obese, 39 overweight, and 72 normal controls; 147 girls and 106 boys) were recruited. Anthropometric indices, body composition, and fasting total lipid profiles were determined. Serum concentrations of 20 sterols, as their free fraction, were analyzed through gas chromatography-mass spectrometry-based metabolite profiling. There were no significant differences in total- and LDL-cholesterols between groups. Serum levels of the main cholesterol precursors, lanosterol (P<0.02) and lathosterol (P<0.0001), were significantly higher in obese children. In addition, they showed positive correlations with waist to hip ratio, body fat percent, and body fat mass. The metabolic ratios of lanosterol and lathosterol to cholesterol were also elevated (P<0.01 both), indicating the up-regulation of cholesterol biosynthesis with childhood obesity. In contrast, the absorption of plant sterols tended to show a compensatory decrease in obese children. Strong correlations between free cholesterol and total- and LDL-cholesterols were observed (r>0.760, P<0.001), while there was no correlation with HDL-cholesterols. The levels of total cholesteryl ester were closely associated with triglyceride (r=0.763, P<0.001). Quantitative results indicate that childhood obesity may increase cholesterol synthesis while maintaining overall cholesterol homeostasis. PMID:25725317

Son, Hyun-Hwa; Kim, Shin Hye; Moon, Ju-Yeon; Chung, Bong Chul; Park, Mi Jung; Choi, Man Ho

2015-05-01

138

Plant extracts and plant-derived compounds: promising players in a countermeasure strategy against radiological exposure.  

PubMed

Radiation exposure leads to several pathophysiological conditions, including oxidative damage, inflammation and fibrosis, thereby affecting the survival of organisms. This review explores the radiation countermeasure properties of fourteen (14) plant extracts or plant-derived compounds against these cellular manifestations. It was aimed at evaluating the possible role of plants or its constituents in radiation countermeasure strategy. All the 14 plant extracts or compounds derived from it and considered in this review have shown some radioprotection in different in vivo, ex-vivo and or in vitro models of radiological injury. However, few have demonstrated advantages over the others. C. majus possessing antioxidant, anti-inflammatory and immunomodulatory effects appears to be promising in radioprotection. Its crude extracts as well as various alkaloids and flavonoids derived from it, have shown to enhance survival rate in irradiated mice. Similarly, curcumin with its antioxidant and the ability to ameliorate late effect of radiation exposure, combined with improvement in survival in experimental animal following irradiation, makes it another probable candidate against radiological injury. Furthermore, the extracts of P. hexandrum and P. kurroa in combine treatment regime, M. piperita, E. officinalis, A. sinensis, nutmeg, genistein and ginsan warrants further studies on their radioprotective potentials. However, one that has received a lot of attention is the dietary flaxseed. The scavenging ability against radiation-induced free radicals, prevention of radiation-induced lipid peroxidation, reduction in radiation cachexia, level of inflammatory cytokines and fibrosis, are some of the remarkable characteristics of flaxseed in animal models of radiation injury. While countering the harmful effects of radiation exposure, it has shown its ability to enhance survival rate in experimental animals. Further, flaxseed has been tested and found to be equally effective when administered before or after irradiation, and against low doses (? 5 Gy) to the whole body or high doses (12-13.5 Gy) to the whole thorax. This is particularly relevant since apart from the possibility of using it in pre-conditioning regime in radiotherapy, it could also be used during nuclear plant leakage/accidents and radiological terrorism, which are not pre-determined scenarios. However, considering the infancy of the field of plant-based radioprotectors, all the above-mentioned plant extracts/plant-derived compounds deserves further stringent study in different models of radiation injury. PMID:24761841

Kma, Lakhan

2014-01-01

139

Plasma membrane lipid–protein interactions affect signaling processes in sterol-biosynthesis mutants in Arabidopsis thaliana  

PubMed Central

The plasma membrane is an important organelle providing structure, signaling and transport as major biological functions. Being composed of lipids and proteins with different physicochemical properties, the biological functions of membranes depend on specific protein–protein and protein–lipid interactions. Interactions of proteins with their specific sterol and lipid environment were shown to be important factors for protein recruitment into sub-compartmental structures of the plasma membrane. System-wide implications of altered endogenous sterol levels for membrane functions in living cells were not studied in higher plant cells. In particular, little is known how alterations in membrane sterol composition affect protein and lipid organization and interaction within membranes. Here, we conducted a comparative analysis of the plasma membrane protein and lipid composition in Arabidopsis sterol-biosynthesis mutants smt1 and ugt80A2;B1. smt1 shows general alterations in sterol composition while ugt80A2;B1 is significantly impaired in sterol glycosylation. By systematically analyzing different cellular fractions and combining proteomic with lipidomic data we were able to reveal contrasting alterations in lipid–protein interactions in both mutants, with resulting differential changes in plasma membrane signaling status. PMID:24672530

Zauber, Henrik; Burgos, Asdrubal; Garapati, Prashanth; Schulze, Waltraud X.

2014-01-01

140

Sterol Structure Determines Miscibility versus Melting Transitions in Lipid Vesicles  

PubMed Central

Lipid bilayer membranes composed of DOPC, DPPC, and a series of sterols demix into coexisting liquid phases below a miscibility transition temperature. We use fluorescence microscopy to directly observe phase transitions in vesicles of 1:1:1 DOPC/DPPC/sterol within giant unilamellar vesicles. We show that vesicles containing the “promoter” sterols cholesterol, ergosterol, 25-hydroxycholesterol, epicholesterol, or dihydrocholesterol demix into coexisting liquid phases as temperature is lowered through the miscibility transition. In contrast, vesicles containing the “inhibitor” sterols androstenolone, coprostanol, cholestenone, or cholestane form coexisting gel (solid) and liquid phases. Vesicles containing lanosterol, a sterol found in the cholesterol and ergosterol synthesis pathways, do not exhibit coexisting phases over a wide range of temperatures and compositions. Although more detailed phase diagrams and precise distinctions between gel and liquid phases are required to fully define the phase behavior of these sterols in vesicles, we find that our classifications of promoter and inhibitor sterols are consistent with previous designations based on fluorescence quenching and detergent resistance. We find no trend in the liquid-liquid or gel-liquid transition temperatures of membranes with promoter or inhibitor sterols and measure the surface fraction of coexisting phases. We find that the vesicle phase behavior is related to the structure of the sterols. Promoter sterols have flat, fused rings, a hydroxyl headgroup, an alkyl tail, and a small molecular area, which are all attributes of “membrane active” sterols. PMID:15951379

Beattie, Mary Elizabeth; Veatch, Sarah L.; Stottrup, Benjamin L.; Keller, Sarah L.

2005-01-01

141

Sterol structure determines miscibility versus melting transitions in lipid vesicles.  

PubMed

Lipid bilayer membranes composed of DOPC, DPPC, and a series of sterols demix into coexisting liquid phases below a miscibility transition temperature. We use fluorescence microscopy to directly observe phase transitions in vesicles of 1:1:1 DOPC/DPPC/sterol within giant unilamellar vesicles. We show that vesicles containing the "promoter" sterols cholesterol, ergosterol, 25-hydroxycholesterol, epicholesterol, or dihydrocholesterol demix into coexisting liquid phases as temperature is lowered through the miscibility transition. In contrast, vesicles containing the "inhibitor" sterols androstenolone, coprostanol, cholestenone, or cholestane form coexisting gel (solid) and liquid phases. Vesicles containing lanosterol, a sterol found in the cholesterol and ergosterol synthesis pathways, do not exhibit coexisting phases over a wide range of temperatures and compositions. Although more detailed phase diagrams and precise distinctions between gel and liquid phases are required to fully define the phase behavior of these sterols in vesicles, we find that our classifications of promoter and inhibitor sterols are consistent with previous designations based on fluorescence quenching and detergent resistance. We find no trend in the liquid-liquid or gel-liquid transition temperatures of membranes with promoter or inhibitor sterols and measure the surface fraction of coexisting phases. We find that the vesicle phase behavior is related to the structure of the sterols. Promoter sterols have flat, fused rings, a hydroxyl headgroup, an alkyl tail, and a small molecular area, which are all attributes of "membrane active" sterols. PMID:15951379

Beattie, Mary Elizabeth; Veatch, Sarah L; Stottrup, Benjamin L; Keller, Sarah L

2005-09-01

142

Genetic instability in calamondin (Citrus madurensis Lour.) plants derived from somatic embryogenesis induced by diphenylurea derivatives.  

PubMed

Somatic embryos were regenerated in vitro from calamondin style-stigma explants cultured in the presence of N (6)-benzylaminopurine (BAP) cytokinin and three synthetic phenylurea derivatives, N-(2-chloro-4-pyridyl)-N-phenylurea (4-CPPU), N-phenyl-N'-benzothiazol-6-ylurea (PBU) and N,N'-bis-(2,3-methilendioxyphenyl)urea (2,3-MDPU). The phenylurea derivative compounds tested at micromolar level (12 muM) were able to induce a percentage of responsive explants significantly higher from that obtained with BAP and hormone-free (HF) conditions. In order to verify the genetic stability of the regenerants, 27 plants coming from different embryogenic events were randomly selected from each different culture condition and evaluated for somaclonal variations using inter-simple sequence repeat and random amplified polymorphic DNA analyses. We observed that 2,3-MDPU and PBU gave 3.7% of somaclonal mutants, whereas 4-CPPU gave 7.4% of mutants. No somaclonal variability was observed when plantlets were regenerated in BAP or HF medium. Although diphenylurea derivatives show a higher embryogenic potential as compared to BAP, they induce higher levels of somaclonal variability. This finding should be taken in consideration when new protocols for clonal propagation are being developed. PMID:17333016

Siragusa, Mirko; Carra, Angela; Salvia, Lidia; Puglia, Anna Maria; De Pasquale, Fabio; Carimi, Francesco

2007-08-01

143

A new triazole, voriconazole (UK-109,496), blocks sterol biosynthesis in Candida albicans and Candida krusei.  

PubMed Central

Voriconazole (UK-109,496) is a novel triazole derivative with potent broad-spectrum activity against various fungi, including some that are inherently resistant to fluconazole, such as Candida krusei. In this study we compared the effect of subinhibitory concentrations of voriconazole and fluconazole on sterol biosynthesis of fluconazole-resistant and -susceptible Candida albicans strains, as well as C. krusei, in an effort to delineate the precise mode of action of voriconazole. Voriconazole MICs ranged from 0.003 to 4 microg/ml, while fluconazole MICs ranged from 0.25 to >64 microg/ml. To investigate the effects of voriconazole and fluconazole on candidal sterols, yeast cells were grown in the absence and presence of antifungals. In untreated C. albicans controls, ergosterol was the major sterol (accounting for 53.6% +/- 2.2% to 71.7% +/- 7.8% of the total) in C. albicans and C. krusei strains. There was no significant difference between the sterol compositions of the fluconazole-susceptible and -resistant C. albicans isolates. Voriconazole treatment led to a decrease in the total sterol content of both C. albicans strains tested. In contrast, exposure to fluconazole did not result in a significant reduction in the total sterol content of the three candidal strains tested (P > 0.5). Gas-liquid chromatographic analysis revealed profound changes in the sterol profiles of both C. albicans strains and of C. krusei in response to voriconazole. This antifungal agent exerted a similar effect on the sterol compositions of both fluconazole-susceptible and -resistant C. albicans strains. Interestingly, a complete inhibition of ergosterol synthesis and accumulation of its biosynthetic precursors were observed in both strains treated with voriconazole. In contrast, fluconazole partially inhibited ergosterol synthesis. Analysis of sterols obtained from a fluconazole-resistant C. albicans strain grown in the presence of different concentrations of voriconazole showed that this agent inhibits ergosterol synthesis in a dose-dependent manner. In C. krusei, voriconazole significantly inhibited ergosterol synthesis (over 75% inhibition). C. krusei cells treated with voriconazole accumulated the following biosynthetic intermediates: squalene, 4,14-dimethylzymosterol, and 24-methylenedihydrolanosterol. Accumulation of these methylated sterols is consistent with the premise that this agent functions by inhibiting fungal P-450-dependent 14alpha-demethylase. As expected, treating C. krusei with fluconazole minimally inhibited ergosterol synthesis. Importantly, our data indicate that voriconazole is more effective than fluconazole in blocking candidal sterol biosynthesis, consistent with the different antifungal potencies of these compounds. PMID:9371355

Sanati, H; Belanger, P; Fratti, R; Ghannoum, M

1997-01-01

144

Lectin cDNA and transgenic plants derived therefrom  

DOEpatents

Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties.

Raikhel, Natasha V. (Okemos, MI)

2000-10-03

145

Assessment of plant-derived hydrocarbons. Final report  

SciTech Connect

A number of hydrocarbon producing plants are evaluated as possible sources of rubber, liquid fuels, and industrial lubricants. The plants considered are Euphorbia lathyris or gopher plant, milkweeds, guayule, rabbit brush, jojoba, and meadow foam. (ACR)

McFadden, K.; Nelson, S.H.

1981-09-30

146

Mechanisms and genetic determinants regulating sterol absorption, circulating LDL levels, and sterol elimination: implications for classification and disease risk  

PubMed Central

This review integrates historical biochemical and modern genetic findings that underpin our understanding of the low-density lipoprotein (LDL) dyslipidemias that bear on human disease. These range from life-threatening conditions of infancy through severe coronary heart disease of young adulthood, to indolent disorders of middle- and old-age. We particularly focus on the biological aspects of those gene mutations and variants that impact on sterol absorption and hepatobiliary excretion via specific membrane transporter systems (NPC1L1, ABCG5/8); the incorporation of dietary sterols (MTP) and of de novo synthesized lipids (HMGCR, TRIB1) into apoB-containing lipoproteins (APOB) and their release into the circulation (ANGPTL3, SARA2, SORT1); and receptor-mediated uptake of LDL and of intestinal and hepatic-derived lipoprotein remnants (LDLR, APOB, APOE, LDLRAP1, PCSK9, IDOL). The insights gained from integrating the wealth of genetic data with biological processes have important implications for the classification of clinical and presymptomatic diagnoses of traditional LDL dyslipidemias, sitosterolemia, and newly emerging phenotypes, as well as their management through both nutritional and pharmaceutical means. PMID:21862702

Calandra, Sebastiano; Tarugi, Patrizia; Speedy, Helen E.; Dean, Andrew F.; Bertolini, Stefano; Shoulders, Carol C.

2011-01-01

147

Mutations in UDP-Glucose:sterol glucosyltransferase in Arabidopsis cause transparent testa phenotype and suberization defect in seeds.  

PubMed

In higher plants, the most abundant sterol derivatives are steryl glycosides (SGs) and acyl SGs. Arabidopsis (Arabidopsis thaliana) contains two genes, UGT80A2 and UGT80B1, that encode UDP-Glc:sterol glycosyltransferases, enzymes that catalyze the synthesis of SGs. Lines having mutations in UGT80A2, UGT80B1, or both UGT80A2 and UGT8B1 were identified and characterized. The ugt80A2 lines were viable and exhibited relatively minor effects on plant growth. Conversely, ugt80B1 mutants displayed an array of phenotypes that were pronounced in the embryo and seed. Most notable was the finding that ugt80B1 was allelic to transparent testa15 and displayed a transparent testa phenotype and a reduction in seed size. In addition to the role of UGT80B1 in the deposition of flavanoids, a loss of suberization of the seed was apparent in ugt80B1 by the lack of autofluorescence at the hilum region. Moreover, in ugt80B1, scanning and transmission electron microscopy reveals that the outer integument of the seed coat lost the electron-dense cuticle layer at its surface and displayed altered cell morphology. Gas chromatography coupled with mass spectrometry of lipid polyester monomers confirmed a drastic decrease in aliphatic suberin and cutin-like polymers that was associated with an inability to limit tetrazolium salt uptake. The findings suggest a membrane function for SGs and acyl SGs in trafficking of lipid polyester precursors. An ancillary observation was that cellulose biosynthesis was unaffected in the double mutant, inconsistent with a predicted role for SGs in priming cellulose synthesis. PMID:19641030

DeBolt, Seth; Scheible, Wolf-Rüdiger; Schrick, Kathrin; Auer, Manfred; Beisson, Fred; Bischoff, Volker; Bouvier-Navé, Pierrette; Carroll, Andrew; Hematy, Kian; Li, Yonghua; Milne, Jennifer; Nair, Meera; Schaller, Hubert; Zemla, Marcin; Somerville, Chris

2009-09-01

148

An update on plant derived anti-androgens.  

PubMed

Anti-androgens are an assorted group of drugs and compounds that reduce the levels or activity of androgen hormones within the human body. Disease states in which this is relevant include polycystic ovarian syndrome, hirsutism, acne, benign prostatic hyperplasia, and endocrine related cancers such as carcinoma of the prostate. We provide an overview and discussion of the use of anti-androgen medications in clinical practice and explore the increasing recognition of the benefits of plant-derived anti-androgens, for example, spearmint tea in the management of PCOS, for which some evidence about efficacy is beginning to emerge. Other agents covered include red reishi, which has been shown to reduce levels 5-alpha reductase, the enzyme that facilitates conversion of testosterone to dihydrotestosterone (DHT); licorice, which has phytoestrogen effects and reduces testosterone levels; Chinese peony, which promotes the aromatization of testosterone into estrogen; green tea, which contains epigallocatechins and also inhibits 5-alpha reductase, thereby reducing the conversion of normal testosterone into the more potent DHT; black cohosh, which has been shown to kill both androgenresponsive and non-responsive human prostate cancer cells; chaste tree, which has a reduces prolactin from the anterior pituitary; and saw palmetto extract, which is used as an anti-androgen although it shown no difference in comparison to placebo in clinical trials. PMID:23843810

Grant, Paul; Ramasamy, Shamin

2012-01-01

149

An Update on Plant Derived Anti-Androgens  

PubMed Central

Anti-androgens are an assorted group of drugs and compounds that reduce the levels or activity of androgen hormones within the human body. Disease states in which this is relevant include polycystic ovarian syndrome, hirsutism, acne, benign prostatic hyperplasia, and endocrine related cancers such as carcinoma of the prostate. We provide an overview and discussion of the use of anti-androgen medications in clinical practice and explore the increasing recognition of the benefits of plant-derived anti-androgens, for example, spearmint tea in the management of PCOS, for which some evidence about efficacy is beginning to emerge. Other agents covered include red reishi, which has been shown to reduce levels 5-alpha reductase, the enzyme that facilitates conversion of testosterone to dihydrotestosterone (DHT); licorice, which has phytoestrogen effects and reduces testosterone levels; Chinese peony, which promotes the aromatization of testosterone into estrogen; green tea, which contains epigallocatechins and also inhibits 5-alpha reductase, thereby reducing the conversion of normal testosterone into the more potent DHT; black cohosh, which has been shown to kill both androgenresponsive and non-responsive human prostate cancer cells; chaste tree, which has a reduces prolactin from the anterior pituitary; and saw palmetto extract, which is used as an anti-androgen although it shown no difference in comparison to placebo in clinical trials. PMID:23843810

Grant, Paul; Ramasamy, Shamin

2012-01-01

150

Triterpene alcohols and sterols of vegetable oils  

Microsoft Academic Search

Triterpene alcohols and sterols were separated by thin-layer chromatography and gas-liquid chromatography from the unsaponifiable\\u000a fractions of the following 18 vegetable oils: linseed, peanut, olive, rice bran, palm kernel, corn, sesame, oiticica, palm,\\u000a coconut, rapeseed, grape seed, sunflower, poppy seed, castor, tea seed, cocoa butter and soybean. Two triterpene alcohols,\\u000a cycloartenol and 24-methylene cycloartanol, were found in all of the

E. Fedeli; A. Lanzani; P. Capella; G. Jacini

1966-01-01

151

50 CFR 23.92 - Are any wildlife or plants, and their parts, products, or derivatives, exempt?  

Code of Federal Regulations, 2010 CFR

...plants, and their parts, products, or derivatives, exempt? 23.92 Section 23...plants, and their parts, products, or derivatives, exempt? (a) All living or dead...recognizable parts, products, and derivatives must meet the requirements of...

2010-10-01

152

50 CFR 23.92 - Are any wildlife or plants, and their parts, products, or derivatives, exempt?  

Code of Federal Regulations, 2012 CFR

...plants, and their parts, products, or derivatives, exempt? 23.92 Section 23...plants, and their parts, products, or derivatives, exempt? (a) All living or dead...recognizable parts, products, and derivatives must meet the requirements of...

2012-10-01

153

50 CFR 23.92 - Are any wildlife or plants, and their parts, products, or derivatives, exempt?  

Code of Federal Regulations, 2013 CFR

...plants, and their parts, products, or derivatives, exempt? 23.92 Section 23...plants, and their parts, products, or derivatives, exempt? (a) All living or dead...recognizable parts, products, and derivatives must meet the requirements of...

2013-10-01

154

Sterol Structure Determines Miscibility versus Melting Transitions in Lipid Vesicles  

Microsoft Academic Search

Lipid bilayer membranes composed of DOPC, DPPC, and a series of sterols demix into coexisting liquid phases below a miscibility transition temperature. We use fluorescence microscopy to directly observe phase transitions in vesicles of 1:1:1 DOPC\\/DPPC\\/sterol within giant unilamellar vesicles. We show that vesicles containing the “promoter” sterols cholesterol, ergosterol, 25-hydroxycholesterol, epicholesterol, or dihydrocholesterol demix into coexisting liquid phases as

Mary Elizabeth Beattie; Sarah L. Veatch; Benjamin L. Stottrup; Sarah L. Keller

2005-01-01

155

Distribution of sterols in the fungi. I - Fungal spores  

NASA Technical Reports Server (NTRS)

Mass spectrometry was used to examine freely extractable sterols from spores of several species of fungi. Ergosterol was the most common sterol produced by any individual species, but it was completely absent from two species belonging to apparently distantly related groups of fungi: the aquatic Phycomycetes and the rust fungi. This fact could have taxonomic or phylogenetic implications. The use of glass capillary columns in the resolution of the sterols is shown to eliminate some of the difficulty inherent in this process.

Weete, J. D.; Laseter, J. L.

1974-01-01

156

Antibiofilm effect of plant derived antimicrobials on Listeria monocytogenes.  

PubMed

The present study investigated the efficacy of sub-inhibitory concentrations (SICs, concentrations not inhibiting bacterial growth) and bactericidal concentrations (MBCs) of four, generally recognized as safe (GRAS), plant-derived antimicrobials (PDAs) in inhibiting Listeria monocytogenes (LM) biofilm formation and inactivating mature LM biofilms, at 37, 25 and 4 °C on polystyrene plates and stainless-steel coupons. In addition, the effect of SICs of PDAs on the expression of LM genes critical for biofilm synthesis was determined by real-time quantitative PCR. The PDAs and their SICs used for inhibition of biofilm were trans-cinnamaldehyde (TC 0.50, 0.75 mM), carvacrol (CR 0.50, 0.65 mM), thymol (TY 0.33, 0.50 mM), and eugenol (EG 1.8, 2.5 mM), whereas the PDA concentrations used for inactivating mature biofilms were 5.0 and 10.0 mM (TC, CR), 3.3 and 5.0 mM (TY), 18.5 and 25.0 mM (EG). All PDAs inhibited biofilm synthesis and inactivated fully formed LM biofilms on both matrices at three temperatures tested (P < 0.05). Real-time quantitative PCR data revealed that all PDAs down-regulated critical LM biofilm-associated genes (P < 0.05). Results suggest that TC, CR, TY, and EG could potentially be used to control LM biofilms in food processing environments, although further studies under commercial settings are necessary. PMID:23764223

Upadhyay, Abhinav; Upadhyaya, Indu; Kollanoor-Johny, Anup; Venkitanarayanan, Kumar

2013-10-01

157

Seasonal changes in minor membrane phospholipid classes, sterols and tocopherols in overwintering insect, Pyrrhocoris apterus.  

PubMed

Ectotherm animals including insects are known to undergo seasonal restructuring of the cell membranes in order to keep their functionality and/or protect their structural integrity at low body temperatures. Studies on insects so far focused either on fatty acids or on composition of molecular species in major phospholipid classes. Here we extend the scope of analysis and bring results on seasonal changes in minor phospholipid classes, lysophospholipids (LPLs), free fatty acids, phytosterols and tocopherols in heteropteran insect, Pyrrhocoris apterus. We found that muscle tissue contains unusually high amounts of LPLs. Muscle and fat body tissues also contain high amounts of ?-sitosterol and campesterol, two phytosterols derived from plant food, while only small amounts of cholesterol are present. In addition, two isomers (? and ?) of tocopherol (vitamin E) are present in quantities comparable to, or even higher than phytosterols in both tissues. Distinct seasonal patterns of sterol and tocopherol concentrations were observed showing a minimum in reproductively active bugs in summer and a maximum in diapausing, cold-acclimated bugs in winter. Possible adaptive meanings of such changes are discussed including: preventing the unregulated transition of membrane lipids from functional liquid crystalline phase to non-functional gel phase; decreasing the rates of ion/solute leakage; silencing the activities of membrane bound enzymes and receptors; and counteracting the higher risk of oxidative damage to PUFA in winter membranes. PMID:23845405

Koštál, Vladimír; Urban, Tomáš; Rimná?ová, Lucie; Berková, Petra; Simek, Petr

2013-09-01

158

Molecular, phenotypic and biosynthetic stability in Dioscorea floribunda plants derived from cryopreserved shoot tips  

Microsoft Academic Search

Shoot tips of Dioscorea floribunda, a medicinal species of yam, were cryopreserved using the vitrification technique, resulting in 87% survival and 30% plant regeneration. Genetic stability of plants derived from cryopreserved shoot tips was evaluated using molecular, morphological and biochemical methods. The random amplified polymorphic DNA (RAPD) analysis of 60 cryopreserved-derived and 20 in vitro grown (control) plantlets showed that

Sangeeta Ahuja; Binay B Mandal; Sonali Dixit; Prem S Srivastava

2002-01-01

159

Fatty Acid-Derived Signals that Induce or Regulate Plant Defenses Against Herbivory  

Microsoft Academic Search

Jasmonic acid and other derivatives of linolenic acid produced in plants by the octadecanoid pathway, as well as the six-carbon fatty acid derivatives called green leaf compounds, play major roles in regulating plant defenses against herbivores. So do also conjugates of linolenic acid with glutamine and glutamate, found in the regurgitant of several lepidopteran larvae, as well as in crickets

James H. Tumlinson; Juergen Engelberth

160

Arabidopsis sterol carrier protein-2 is required for normal development of seeds and seedlings  

Microsoft Academic Search

The Arabidopsis thaliana sterol carrier protein-2 (AtSCP2) is a small, basic and peroxisomal protein that in vitro enhances the transfer of lipids between membranes. AtSCP2 and all other plant SCP-2 that have been identified are single-domain polypeptides, whereas in many other eukaryotes SCP-2 domains are expressed in the terminus of multidomain polypepti- des. The AtSCP2 transcript is expressed in all

Bing Song Zheng; Elin Ronnberg; Lenita Viitanen; Tiina A. Salminen; Krister Lundgren; Thomas Moritz; Johan Edqvist

2008-01-01

161

Sterols and Oxidized Sterols in Feed Ingredients Obtained from Chemical and Physical Refining Processes of Fats and Oils  

Microsoft Academic Search

The by-products obtained from conventional chemical and physical refining processes for edible fats and oils are important\\u000a sources of valuable fatty components such as sterols, tocopherols, fatty acids, etc., and are also used as ingredients in\\u000a animal feed formulations. Reports on sterol composition and content are limited, and the levels of oxidized sterols in these\\u000a valuable by-products are unknown. This

Sarojini J. K. A. Ubhayasekera; Paresh C. Dutta

2009-01-01

162

The role of sterol-C4-methyl oxidase in epidermal biology  

PubMed Central

Deficiency of sterol C4 methyl oxidase, encoded by the SC4MOL gene, has recently been described in four patients from three different families. All of the patients presented with microcephaly, congenital cataracts, and growth delay in infancy. The first patient has suffered since the age of six years from severe, diffuse, psoriasiform dermatitis, sparing only her palms. She is now 20 years old. The second patient is a 5 year old girl who has just started to develop dry skin and hair changes. The third and fourth patients are a pair of affected siblings with a severe skin condition since infancy. Quantitative sterol analysis of plasma and skin scales from all four patients showed marked elevation of 4?-methyl- and 4, 4?-dimethylsterols, consistent with a deficiency in the first step of sterol C4 demethylation in cholesterol biosynthesis. Mutations in the SC4MOL have been identified in all of the patients. SC4MOL deficiency is the first autosomal recessive disorder identified in the sterol demethylation complex. Cellular studies with patient-derived fibroblasts have shown a higher mitotic rate than control cells in cholesterol-depleted medium, with increased de novo cholesterol biosynthesis and accumulation of methylsterols. Immunologic analyses of granulocytes and B cells from patients and obligate carriers in the patients’ families indicated dysregulation of immune-related receptors. Inhibition of sterol C4 methyl oxidase in human transformed lymphoblasts induced activation of the cell cycle. Additional studies also demonstrated diminished EGFR signaling and disrupted vesicular trafficking in cells from the affected patients. These findings suggest that methylsterols play an important role in epidermal biology by their influence on cell proliferation, intracellular signaling, vesicular trafficking and immune response. SC4MOL is situated within the psoriasis susceptibility locus PSORS9, and may be a genetic risk factor for common skin conditions. PMID:24144731

He, Miao; Smith, Laurie D.; Chang, Richard; Li, Xueli; Vockley, Jerry

2013-01-01

163

Lectin cDNA and transgenic plants derived therefrom  

DOEpatents

Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties. GOVERNMENT RIGHTS This application was funded under Department of Energy Contract DE-AC02-76ER01338. The U.S. Government has certain rights under this application and any patent issuing thereon. .

Raikhel, N.V.

1994-01-04

164

Lectin cDNA and transgenic plants derived therefrom  

DOEpatents

Transgenic plants containing cDNA encoding Gramineae lectin are described. The plants preferably contain cDNA coding for barley lectin and store the lectin in the leaves. The transgenic plants, particularly the leaves exhibit insecticidal and fungicidal properties. GOVERNMENT RIGHTS This application was funded under Department of Energy Contract DE-AC02-76ER01338. The U.S. Government has certain rights under this application and any patent issuing thereon.

Raikhel, Natasha V. (Okemos, MI)

1994-01-04

165

Plants as bioindicators of natural and anthropogenically derived contamination  

SciTech Connect

The visual appearance of plants, in combination with the presence of particular key species or assemblages, may provide clues to the occurrence of contaminants in the underlying strata. Chemical analysis of plant material, either collected from the field or from laboratory-based plant growth trials, can also provide a measure of the environmental mobility of a contaminant. This article discusses the role of plants as bioinidicators with reference to examples of preliminary contaminated-land-assessment, air pollution monitoring, and studies into the environmental significance of contaminants in domestic and codisposed refuse. 9 refs., 6 tabs.

Gregson, S.; Clifton, S.; Roberts., R.D. [Applied Environmental Research Centre Ltd., Colchester (United Kingdom)

1994-07-01

166

X-ray Structure of 4,4?-Dihydroxybenzophenone Mimicking Sterol Substrate in the Active Site of Sterol 14?-Demethylase (CYP51)*S??  

PubMed Central

A universal step in the biosynthesis of membrane sterols and steroid hormones is the oxidative removal of the 14?-methyl group from sterol precursors by sterol 14?-demethylase (CYP51). This enzyme is a primary target in treatment of fungal infections in organisms ranging from humans to plants, and development of more potent and selective CYP51 inhibitors is an important biological objective. Our continuing interest in structural aspects of substrate and inhibitor recognition in CYP51 led us to determine (to a resolution of 1.95Ĺ) the structure of CYP51 from Mycobacterium tuberculosis (CYP51Mt) co-crystallized with 4,4?-dihydroxybenzophenone (DHBP), a small organic molecule previously identified among top type I binding hits in a library screened against CYP51Mt. The newly determined CYP51Mt-DHBP structure is the most complete to date and is an improved template for three-dimensional modeling of CYP51 enzymes from fungal and prokaryotic pathogens. The structure demonstrates the induction of conformational fit of the flexible protein regions and the interactions of conserved Phe-89 essential for both fungal drug resistance and catalytic function, which were obscure in the previously characterized CYP51Mt-estriol complex. DHBP represents a benzophenone scaffold binding in the CYP51 active site via a type I mechanism, suggesting (i) a possible new class of CYP51 inhibitors targeting flexible regions, (ii) an alternative catalytic function for bacterial CYP51 enzymes, and (iii) a potential for hydroxybenzophenones, widely distributed in the environment, to interfere with sterol biosynthesis. Finally, we show the inhibition of M. tuberculosis growth by DHBP in a mouse macrophage model. PMID:18367444

Eddine, Ali Nasser; von Kries, Jens P.; Podust, Mikhail V.; Warrier, Thulasi; Kaufmann, Stefan H. E.; Podust, Larissa M.

2008-01-01

167

Immunization against Rabies with Plant-Derived Antigen  

Microsoft Academic Search

We previously demonstrated that recombinant plant virus particles containing a chimeric peptide representing two rabies virus epitopes stimulate virus neutralizing antibody synthesis in immunized mice. We show here that mice immunized intraperitoneally or orally (by gastric intubation or by feeding on virus-infected spinach leaves) with engineered plant virus particles containing rabies antigen mount a local and systemic immune response. After

Anna Modelska; Bernard Dietzschold; N. Sleysh; Zhen Fang Fu; Klaudia Steplewski; D. Craig Hooper; Hilary Koprowski; Vidadi Yusibov

1998-01-01

168

PLANT-DERIVED COMPOUNDS ACTIVE AGAINST MELOIDOGYNE INCOGNITA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Products from two plant genera, Plantago and Eugenia, were tested for effects on the root-knot nematode Meloidogyne incognita. Extracts from P. lanceolata and P. rugelii were also evaluated for toxicity to the plant-pathogenic fungi Fusarium oxysporum f. sp. gladioli, Phytophthora capsici, Pythium ...

169

Substrate Preferences and Catalytic Parameters Determined by Structural Characteristics of Sterol 14[alpha]-Demethylase (CYP51) from Leishmania infantum  

SciTech Connect

Leishmaniasis is a major health problem that affects populations of {approx}90 countries worldwide, with no vaccine and only a few moderately effective drugs. Here we report the structure/function characterization of sterol 14{alpha}-demethylase (CYP51) from Leishmania infantum. The enzyme catalyzes removal of the 14{alpha}-methyl group from sterol precursors. The reaction is essential for membrane biogenesis and therefore has great potential to become a target for antileishmanial chemotherapy. Although L. infantum CYP51 prefers C4-monomethylated sterol substrates such as C4-norlanosterol and obtusifoliol (V{sub max} of {approx}10 and 8 min{sup -1}, respectively), it is also found to 14{alpha}-demethylate C4-dimethylated lanosterol (V{sub max} = 0.9 min{sup -1}) and C4-desmethylated 14{alpha}-methylzymosterol (V{sub max} = 1.9 min{sup -1}). Binding parameters with six sterols were tested, with K{sub d} values ranging from 0.25 to 1.4 {mu}m. Thus, L. infantum CYP51 is the first example of a plant-like sterol 14{alpha}-demethylase, where requirements toward the composition of the C4 atom substituents are not strict, indicative of possible branching in the postsqualene portion of sterol biosynthesis in the parasite. Comparative analysis of three CYP51 substrate binding cavities (Trypanosoma brucei, Trypanosoma cruzi, and L. infantum) suggests that substrate preferences of plant- and fungal-like protozoan CYP51s largely depend on the differences in the enzyme active site topology. These minor structural differences are also likely to underlie CYP51 catalytic rates and drug susceptibility and can be used to design potent and specific inhibitors.

Hargrove, Tatiana Y.; Wawrzak, Zdzislaw; Liu, Jialin; Nes, W. David; Waterman, Michael R.; Lepesheva, Galina I. (Vanderbilt); (TTU); (NWU)

2012-05-14

170

Detailed sterol compositions of two pathogenic rust fungi.  

PubMed

Teliospores of cedar-apple rust Gymnosporangium juniperi-virginianae were collected from the eastern red cedar Juniperus virginiana, and aeciospores of quince rust G. clavipes were collected from the fruit of English hawthorn Crataegus laevigata. The sterol fractions were separated by HPLC, and their identities were determined by 600 MHz 1H NMR. Twenty-six sterols were isolated from G. juniperi-virginianae and 18 sterols were isolated from G. clavipes. The principal sterol of both fungi was (Z)-stigmasta-7,24(28)-dien-3beta-ol. Other major sterols were (24S)-ergost-7-en-3beta-ol, (24S)-stigmast-7-en-3beta-ol, and (24S)-stigmasta-5,7-dien-3beta-ol. The sterols of the hosts were found to be very different from those of the fungi. The 24-alkyl sterols of the fungi had the 24alpha-configuration, whereas those of the hosts had the 24beta-configuration. Similarities to the sterol composition of the AIDS pneumonia fungus Pneumocystis carinii are discussed. PMID:15638244

Giner, José-Luis; Zhao, Hui

2004-08-01

171

STEROLS AS BIOMARKERS IN GYMNODINIUM BREVE DISTRIBUTION IN DINOFLAGELLATES  

EPA Science Inventory

The sterol composition of marine microalgae has been shown to be a chemotaxonomic property potentially of value in distinguishing members of different algal classes. For example, members of the class Dinophyceae display sterol compositions ranging from as few as two (cholesterol ...

172

Plant-derived Compounds for the Treatment of Retroviral Diseases  

Cancer.gov

NIH Researchers have identified Englerin A and its derivatives as potent and specific activators of viral replication in infected T cells (with a decrease of about 70% of activated T-reg population following ex-vivo PBMCs treatment).

173

The Evolution of Sterol Biosynthesis in Bacteria: In Situ Fluorescence Localization of Sterols in the Nucleoid Bacterium Gemmata obscuriglobus  

NASA Astrophysics Data System (ADS)

The biosynthesis of sterols is generally regarded as a eukaryotic process. The first enzymatic step in the production of sterols requires molecular oxygen. Therefore, both the origin of eukaryotes and the evolution of sterol biosynthesis were thought to postdate the rise of oxygen in earth's atmosphere, until Brocks et al. discovered steranes in rocks aged 2.7 Ga (1). Many prokaryotes produce hopanoids, sterol-like compounds that are synthesized from the common precursor squalene without the use of molecular oxygen. However, a few bacterial taxa are also known to produce sterols, suggesting this pathway could precede the rise of oxygen (2, 3). Recently, we discovered the shortest sterol-producing biosynthetic pathway known to date in the bacterium Gemmata obscuriglobus (4). Using genomic searches, we found that Gemmata has the enzymes necessary for synthesis of sterols, and lipid analyses showed that the sterols produced are lanosterol and its isomer parkeol. Gemmata is a member of the Planctomycetes, an unusual group of bacteria, all of the known species of which contain intracellular compartmentalization. Among the Planctomycetes, Gemmata uniquely is the only prokaryote known to contain a double-membrane-bounded nuclear body (5). Since sterols usually are found in eukaryotes, and Gemmata has a eukaryote-like nuclear organelle, we investigated the location of the sterols within Gemmata to postulate whether they play a role in stabilization of the nuclear membrane and control of genomic organization. We used the sterol-specific fluorescent dye Filipin III in conjunction with fluorescent dyes for internal and external cellular membranes in order to determine whether the sterols are located in the nuclear body membrane, external membrane, or both. We found that sterols in Gemmata are concentrated in the internal membrane, implying that they function in maintaining this unusual cellular component. It is notable that Gemmata also produce hopanoids, suggesting that they acquired the ability to produce sterols for a specialized function related to their nuclear membrane. 1. Brocks, J.J., et al., Science 285:1033-36 (1999). 2. Bird, C.W., et al., Nature 230:473-74 (1971). 3. Bode, H.B., et al., Mol. Microbiol. 47:471-81 (2003). 4. Pearson, A., et al., Proc. Natl. Acad. Sci. USA 100:15352-57 (2003). 5. Fuerst, J.A. and R.I. Webb, Proc. Natl. Acad. Sci. USA 88:8184-88 (1991).

Budin, M.; Jorgenson, T. L.; Pearson, A.

2004-12-01

174

Survey of extrachromosomal circular DNA derived from plant satellite repeats  

Microsoft Academic Search

BACKGROUND: Satellite repeats represent one of the most dynamic components of higher plant genomes, undergoing rapid evolutionary changes of their nucleotide sequences and abundance in a genome. However, the exact molecular mechanisms driving these changes and their eventual regulation are mostly unknown. It has been proposed that amplification and homogenization of satellite DNA could be facilitated by extrachromosomal circular DNA

Alice Navrátilová; Andrea Koblížková; Ji?í Macas

2008-01-01

175

Regeneration of anther-derived plants of Hyoscyamus niger L.  

PubMed

Anthers of Hyoscyamus niger L. were cultured by two different methods. In the first method anthers were cultured in the dark in the late tetrad stage of microspore development on the basal medium of Nitsch and Nitsch (Science 163, 85-87; 1969) supplemented with 5 or 10 mg/l 2,4-dichlorophenoxyacetic acid. The callus which developed was able to produce a large number of plants under photoperiodic conditions of 16 h light from fluorescent tubes at 28° and 20° during the dark cycle. Cytological analysis revealed that about 50% of these plants were haploid. A further imporvement to raise the level of haploids by the use of p-fluorophenylalanine was not achieved. In the second method anthers were cultured in the early mononucleate stage of microspore development on the basal medium of Nitsch and Nitsch which was little modified under various conditions. The largest number of plants which developed directly by embryoids was observed on the medium of Nitsch without indolylacetic acid under photoperiodic conditions of 16 h fluorescent light at 28° and 8 h dark at 20°. Cytological examination determined that approximately 70% of the plants were diploid. A genetic marker was used to ensure homozygoty of the diploid regenerates. 98% of the regenerates which developed via callus as well as by direct formation of embryoids were found to be homozygous and originated therefore from generative cells. PMID:24430282

Corduan, G

1975-01-01

176

PLANT DERIVED NATURAL PRODUCTS EXHIBITING ACTIVITY AGAINST FORMOSAN SUBTERRANEAN TERMITES (COPTOTERMES FORMOSANUS)  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Formosan subterranean termite, Coptotermes formosanus, is among the most devastating termite pests. Natural products derived from plant extracts were tested in a discovery program for effective, environmentally friendly termite control agents. Among the natural products that were tested, vulgaro...

177

6-methoxybenzoxazolinone: A Plant Derivative that Stimulates Reproduction in Microtus montanus  

Microsoft Academic Search

A plant-derived cyclic carbamate, 6-methoxybenzoxazolinone, that stimulates reproductive activity in Microtus montanus has been isolated. This nonestrogenic compound may be a naturally occurring environmental cue affecting reproductive cycles in many mammals.

Edward H. Sanders; Pete D. Gardner; Patricia J. Berger; Norman C. Negus

1981-01-01

178

Quinones derived from plant secondary metabolites as anti-cancer agents.  

PubMed

Quinones are plant-derived secondary metabolites that present some anti-proliferation and anti-metastasis effects in various cancer types both in vitro and in vivo. This review focuses on the anti-cancer prospects of plant-derived quinones, namely, aloe-emodin, juglone, ?-lapachol, plumbagin, shikonin, and thymoquinone. We intend to summarize their anti-cancer effects and investigate the mechanism of actions to promote the research and development of anti-cancer agents from quinones. PMID:22931417

Lu, Jin-Jian; Bao, Jiao-Lin; Wu, Guo-Sheng; Xu, Wen-Shan; Huang, Ming-Qing; Chen, Xiu-Ping; Wang, Yi-Tao

2013-03-01

179

Spectral Characterization of Plant-Derived Dissolved Organic Matter  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dissolved organic matter (DOM) derived from fresh or early-stage decomposing soil amendment materials may play an important role in the process of organic matter accumulation. The DOM can influence many chemical processes, due to its reactivity with both soil solution components and soil surfaces. W...

180

High-sensitivity measurement of diverse vascular plant-derived biomarkers in high-altitude ice cores  

E-print Network

High-sensitivity measurement of diverse vascular plant-derived biomarkers in high-altitude ice of diverse vascular plant- derived biomarkers in high-altitude ice cores, Geophys. Res. Lett., 36, L13501-volatile organic compounds derived from burned and fresh vascular plant sources and preserved in high- altitude ice

Howat, Ian M.

181

Cycads: evolutionary innovations and the role of plant-derived neurotoxins.  

PubMed

Cycads are an important relic from the past and represent the oldest living seed plants. Cycads have been instrumental in our understanding the evolution of angiosperms and gymnosperms because they have recognizable morphological characteristics intermediate between less-recently evolved plants such as ferns and more-derived (advanced) plants including the angiosperms. Cycads also produce several compounds that are carcinogenic and neurotoxic. Because of their unique placement in terrestrial plant evolution, molecular studies should help to define the origins of structures that led to the rise of seed plants and the role of neurotoxic compounds that are found in cycads. PMID:13678912

Brenner, Eric D; Stevenson, Dennis W; Twigg, Richard W

2003-09-01

182

Immunization against Rabies with Plant-Derived Antigen  

NASA Astrophysics Data System (ADS)

We previously demonstrated that recombinant plant virus particles containing a chimeric peptide representing two rabies virus epitopes stimulate virus neutralizing antibody synthesis in immunized mice. We show here that mice immunized intraperitoneally or orally (by gastric intubation or by feeding on virus-infected spinach leaves) with engineered plant virus particles containing rabies antigen mount a local and systemic immune response. After the third dose of antigen, given intraperitoneally, 40% of the mice were protected against challenge infection with a lethal dose of rabies virus. Oral administration of the antigen stimulated serum IgG and IgA synthesis and ameliorated the clinical signs caused by intranasal infection with an attenuated rabies virus strain.

Modelska, Anna; Dietzschold, Bernard; Sleysh, N.; Fu, Zhen Fang; Steplewski, Klaudia; Hooper, D. Craig; Koprowski, Hilary; Yusibov, Vidadi

1998-03-01

183

Mycotoxins biosynthesized by plant-derived Fusarium isolates.  

PubMed

There is little information on secondary metabolites produced by Fusaria infecting crop plants other than cereals. Many members of Fusarium genus have the ability to colonise perennial crops with only scarce infection or disease symptoms or with no symptoms at all while still being detectable. Even in case of such asymptomatic infection, significant mycotoxin contamination of the plant tissues is possible. The aim of this study was to characterise the spectrum of Fusarium species isolates obtained from different plant hosts (like asparagus, garlic, pineapple, banana, rhubarb, peppers, rice, maize, wheat, and oncidium) and evaluate their ability to biosynthesize the most common mycotoxins in vitro. Among the F.proliferatum isolates, up to 57 % of them biosynthesized fumonisins at very high mass fractions, amounting to above 1000 ?g g(-1), while other Fusarium species such as F. verticillioides, F. lactis, F. polyphialydicum, F. concentricum, F. temperatum, and F. fujikuroi formed fumonisins mostly at much lower level. Only F. ananatum and F. oxysporum did not produce these toxins. Co-occurrence of FBs with other mycotoxins [moniliformin (MON) and beauvericin (BEA)] was often observed and it was mainly F. proliferatum species that formed both mycotoxins (0.4 ?g g(-1) to 41.1 ?g g(-1) BEA and 0.1 ?g g(-1) to 158.5 ?g g(-1) MON). PMID:23334038

Wa?kiewicz, Agnieszka; St?pie?, ?ukasz

2012-12-01

184

How Plants Sense Wounds: Damaged-Self Recognition Is Based on Plant-Derived Elicitors and Induces Octadecanoid Signaling  

PubMed Central

Background Animal-derived elicitors can be used by plants to detect herbivory but they function only in specific insect–plant interactions. How can plants generally perceive damage caused by herbivores? Damaged-self recognition occurs when plants perceive molecular signals of damage: degraded plant molecules or molecules localized outside their original compartment. Methodology/Principal Findings Flame wounding or applying leaf extract or solutions of sucrose or ATP to slightly wounded lima bean (Phaseolus lunatus) leaves induced the secretion of extrafloral nectar, an indirect defense mechanism. Chemically related molecules that would not be released in high concentrations from damaged plant cells (glucose, fructose, salt, and sorbitol) did not elicit a detectable response, excluding osmotic shock as an alternative explanation. Treatments inducing extrafloral nectar secretion also enhanced endogenous concentrations of the defense hormone jasmonic acid (JA). Endogenous JA was also induced by mechanically damaging leaves of lima bean, Arabidopsis, maize, strawberry, sesame and tomato. In lima bean, tomato and sesame, the application of leaf extract further increased endogenous JA content, indicating that damaged-self recognition is taxonomically widely distributed. Transcriptomic patterns obtained with untargeted 454 pyrosequencing of lima bean in response to flame wounding or the application of leaf extract or JA were highly similar to each other, but differed from the response to mere mechanical damage. We conclude that the amount or concentration of damaged-self signals can quantitatively determine the intensity of the wound response and that the full damaged-self response requires the disruption of many cells. Conclusions/Significance Numerous compounds function as JA-inducing elicitors in different plant species. Most of them are, contain, or release, plant-derived molecular motifs. Damaged-self recognition represents a taxonomically widespread mechanism that contributes to the perception of herbivore feeding by plants. This strategy is independent of insect-derived elicitors and, therefore, allows plants to maintain evolutionary control over their interaction with herbivores. PMID:22347382

Heil, Martin; Ibarra-Laclette, Enrique; Adame-Álvarez, Rosa M.; Martínez, Octavio; Ramirez-Chávez, Enrique; Molina-Torres, Jorge; Herrera-Estrella, Luis

2012-01-01

185

Recent Advances in the Discovery and Development of Plant-derived Chemotherapeutic Agents  

Microsoft Academic Search

Plants have long served as traditional herbal medicines, and natural products make excellent leads for new drug development. New plant-derived medicines can come from three sources: single active principles, active fractions, and validated prescriptions. Conventionally, for single active compounds, lead discovery and drug development involve highly efficient bio- activity-directed fractionation and isolation (BDFI) coupled with structural characterization, analog synthesis, and

Kuo-Hsiung Lee

2005-01-01

186

Employment of a refuse derived fuel (r. d. f. ) in low power thermal plants  

Microsoft Academic Search

One of the new energy sources under experimentation is the municipal solid wastes, from which it is possible to recover a refuse derived fuel (r.d.f.) suitable to be burnt in electric power facilities, cement kilns and other thermal plants. The ''Istituto di Fisica Tecnica'' of ''Politecnico di Milano'' has set up a pilot plant for the testing of a combustion

S. Arosio; L. G. Cassitto; A. B. Crescenti; G. Sotiga

1980-01-01

187

Involvement of heme biosynthesis in control of sterol uptake by Saccharomyces cerevisiae.  

PubMed Central

Wild-type Saccharomyces cerevisiae do not accumulate exogenous sterols under aerobic conditions, and a mutant allele conferring sterol auxotrophy (erg7) could be isolated only in strains with a heme deficiency. delta-Aminolevulinic acid (ALA) fed to a hem1 (ALA synthetase-) erg7 (2,3-oxidosqualene cyclase-) sterol-auxotrophic strain of S. cerevisiae inhibited sterol uptake, and growth was negatively affected when intracellular sterol was depleted. The inhibition of sterol uptake (and growth of sterol auxotrophs) by ALA was dependent on the ability to synthesize heme from ALA. A procedure was developed which allowed selection of strains which would take up exogenous sterols but had no apparent defect in heme or ergosterol biosynthesis. One of these sterol uptake control mutants possessed an allele which allowed phenotypic expression of sterol auxotrophy in a heme-competent background. PMID:3891725

Lewis, T A; Taylor, F R; Parks, L W

1985-01-01

188

Correlation of Pseudocholinesterase Inhibition and Plant Growth Retardation by Quaternary Ammonium Derivatives of (+)Limonene  

Microsoft Academic Search

THE terpene hydrocarbon (+)-limonene is widely distributed in nature and comprises more than 95 per cent of distilled citrus peel oils. As part of a study of limonene derivatives having possible biological activity, I reported the synthesis of a number of quaternary ammonium compounds which are plant growth retardants1,2. Several of these derivatives also inhibited human blood serum (pseudo) cholinesterase

William F. Newhall

1969-01-01

189

Ribulose Bisphosphate Carboxylase Activity in Anther-Derived Plants of Saintpaulia ionantha Wendl. Shag 1  

PubMed Central

Plants obtained from anther culture of the African violet, Saintpaulia ionantha Wendl. `Shag' and vegetatively cloned copies of the parent anther donor plant were examined for their ploidy and ribulose-1,5-biphosphate carboxylase (RuBPcase) activity. The cloned parent plants were all diploid and did not vary much in their nuclear DNA, chlorophyll, and RuBPcase activity. Some of the anther-derived plants were similar to the parent plants while others were not. Different levels of ploidy were observed among the androgenetic plants. RuBPcase activities higher than that of the parent plants were found in some anther-derived plants. However, there was no direct correlation between ploidy and RuBPcase activity. Expression of nuclear genes from a single parent in the anther-derived plants and it's diploidization or plastid changes during early stages of microsporogenesis or androgenesis are suggested as possible reasons for the variations observed among them. This could be a useful technique to obtain physiological variants which could be agronomically desirable. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:16663273

Bhaskaran, Shyamala; Smith, Roberta H.; Finer, John J.

1983-01-01

190

Lipids of a Sterol-Nonrequiring Mycoplasma  

PubMed Central

The lipids of the sterol nonrequiring Mycoplasma strain S743 were found to include both ester glycerophosphatides (phosphatidylglycerol, acylphosphatidylglycerol, and diphosphatidylglycerol) and ceramide glycerophosphate compounds containing N-hydroxyacyl groups. The major phosphosphingolipid was tentatively identified as a hydroxyceramidephosphorylglycerol containing an O-acyl group. These compounds became labeled during growth in the presence of 32P-orthophosphate, 14C-glycerol, or 14C-palmitate. The lipid fraction also contained free long-chain base. 14C-palmitate was converted to labeled sphinganine. The long-chain base composition of the lipids was modified by growing the organisms in media containing different fatty acids, which were converted to bases containing two more C atoms per molecule. Ninety per cent of the long-chain base from cells grown in medium supplemented with elaidate consisted of monounsaturated C20 base. Images PMID:5489436

Plackett, P.; Smith, P. F.; Mayberry, W. R.

1970-01-01

191

Oxygen Sensing: Getting Pumped by Sterols  

NSDL National Science Digital Library

Oxygen plays a pivotal role in the maintenance of life for all eukaryotes, with the exception of strict anaerobes. Eukaryotes have developed mechanisms to sense and respond to decreased oxygen levels. How eukaryotes sense oxygen is still not fully understood. What is (or are) the oxygen sensor(s)? This question has vital physiological and pathophysiological implications, because all living aerobic organisms have adaptive mechanisms to maintain oxygen homeostasis. A recent report describes a novel eukaryotic oxygen-sensing mechanism in the fission yeast Schizosaccharomyces pombe, involving the depletion of sterols as a trigger to induce gene expression in response to decreased oxygen levels. It is not yet clear whether this mechanism is involved in the mammalian response to hypoxia, possibly in conjunction with activation of one or both of the hypoxia-inducible factor (HIF-1 or HIF-2) transcription factors.

Brooke M. Emerling (Northwestern University Medical School; Department of Medicine REV)

2005-06-21

192

Terpenoids and sterols from some Japanese mushrooms.  

PubMed

Over the past twenty years, our research group has been studying the chemical constituents of mushrooms. From nineteen species, namely, Amanita virgineoides Bas (Amanitaceae), Daedaleopsis tricolor (Bull.: Fr.) Bond. et Sing. (Polyporaceae), Grifolafrondosa (Fr.) S. F. Gray (Polyporaceae), Hericium erinaceum (Bull.: Fr.) Pers. (Hericiaceae), Hypsizigus marmoreus (Peck) Bigelow (Tricholomataceae), Lactarius piperatus (Scop.: Fr.) S. F. Gray (Russulaceae), Lentinula edodes (Berk.) Sing. (Pleurotaceae), Lyophyllyum connatum (Schum.: Fr.) Sing. (Tricholomataceae), Naematoloma sublateritium (Fr.) Karst. (Strophariaceae), Ompharia lapidescens Schroeter (Polyporaceae), Panellus serotinus (Pers.: Fr.) Kuhn. (Tricholomataceae), Pholiota nameko (T. Ito) S. Ito et Imai in Imai (Strophariaceae), Pleurotus eringii (DC.: Fr.) Quel. (Pleurotaceae), Polyporus umbellatus Fries (Polyporaceae), Russula delica Fr. (Russulaceae), Russula sanguinea (Bull.) Fr. (Russulaceae), Sarcodon aspratus (Berk.) S. Ito (Thelephoraceae), Tricholoma matsutake (S. Ito et Imai) Sing. (Tricholomataceae), and Tricholomaportentosum (Fr.) Quel. (Tricholomataceae), we isolated eight new sesquiterpenoids, six new meroterpenoids, three new triterpenoids, and twenty eight new sterols. In this review, structural features of these new compounds are discussed. PMID:24689228

Yaoita, Yasunori; Kikuchi, Masao; Machida, Koichi

2014-03-01

193

Plant-derived health: the effects of turmeric and curcuminoids.  

PubMed

Plants contain numerous polyphenols, which have been shown to reduce inflammation and hereby to increase resistance to disease. Examples of such polyphenols are isothiocyanates in cabbage and broccoli, epigallocatechin in green tee, capsaicin in chili peppers, chalones, rutin and naringenin in apples, resveratrol in red wine and fresh peanuts and curcumin/curcuminoids in turmeric. Most diseases are maintained by a sustained discreet but obvious increased systemic inflammation. Many studies suggest that the effect of treatment can be improved by a combination of restriction in intake of proinflammatory molecules such as advanced glycation end products (AGE), advanced lipoperoxidation end products (ALE), and rich supply of antiinflammatory molecules such as plant polyphenols. To the polyphenols with a bulk of experimental documentation belong the curcuminoid family and especially its main ingredient, curcumin. This review summarizes the present knowledge about these turmericderived ingredients, which have proven to be strong antioxidants and inhibitors of cyclooxigenase-2 (COX-2), lipoxygenase (LOX) and nuclear factor kappa B (NF-kappaB) but also AGE. A plethora of clinical effects are reported in various experimental diseases, but clinical studies in humans are few. It is suggested that supply of polyphenols and particularly curcuminoids might be value as complement to pharmaceutical treatment, but also prebiotic treatment, in conditions proven to be rather therapy-resistant such as Crohn's, long-stayed patients in intensive care units, but also in conditions such as cancer, liver cirrhosis, chronic renal disease, chronic obstructive lung disease, diabetes and Alzheimer's disease. PMID:19721899

Bengmark, S; Mesa, M D; Gil, A

2009-01-01

194

Plant-derived therapeutics for the treatment of metabolic syndrome  

PubMed Central

Metabolic syndrome is defined as a set of coexisting metabolic disorders that increase an individual’s likelihood of developing type 2 diabetes, cardiovascular disease and stroke. Medicinal plants, some of which have been used for thousands of years, serve as an excellent source of bioactive compounds for the treatment of metabolic syndrome because they contain a wide range of phytochemicals with diverse metabolic effects. In order for botanicals to be effectively used against metabolic syndrome, however, botanical preparations must be characterized and standardized through the identification of their active compounds and respective modes of action, followed by validation in controlled clinical trials with clearly defined endpoints. This review assesses examples of commonly known and partially characterized botanicals to describe specific considerations for the phytochemical, preclinical and clinical characterization of botanicals associated with metabolic syndrome. PMID:20872313

Graf, Brittany L; Raskin, Ilya; Cefalu, William T; Ribnicky, David M

2011-01-01

195

Vasodilator compounds derived from plants and their mechanisms of action.  

PubMed

The present paper reviews vasodilator compounds isolated from plants that were reported in the past 22 years (1990 to 2012) and the different mechanisms of action involved in their vasodilator effects. The search for reports was conducted in a comprehensive manner, intending to encompass those metabolites with a vasodilator effect whose mechanism of action involved both vascular endothelium and arterial smooth muscle. The results obtained from our bibliographic search showed that over half of the isolated compounds have a mechanism of action involving the endothelium. Most of these bioactive metabolites cause vasodilation either by activating the nitric oxide/cGMP pathway or by blocking voltage-dependent calcium channels. Moreover, it was found that many compounds induced vasodilation by more than one mechanism. This review confirms that secondary metabolites, which include a significant group of compounds with extensive chemical diversity, are a valuable source of new pharmaceuticals useful for the treatment and prevention of cardiovascular diseases. PMID:23685938

Luna-Vázquez, Francisco J; Ibarra-Alvarado, César; Rojas-Molina, Alejandra; Rojas-Molina, Isela; Zavala-Sánchez, Miguel Angel

2013-01-01

196

Combating Pathogenic Microorganisms Using Plant-Derived Antimicrobials: A Minireview of the Mechanistic Basis  

PubMed Central

The emergence of antibiotic resistance in pathogenic bacteria has led to renewed interest in exploring the potential of plant-derived antimicrobials (PDAs) as an alternative therapeutic strategy to combat microbial infections. Historically, plant extracts have been used as a safe, effective, and natural remedy for ailments and diseases in traditional medicine. Extensive research in the last two decades has identified a plethora of PDAs with a wide spectrum of activity against a variety of fungal and bacterial pathogens causing infections in humans and animals. Active components of many plant extracts have been characterized and are commercially available; however, research delineating the mechanistic basis of their antimicrobial action is scanty. This review highlights the potential of various plant-derived compounds to control pathogenic bacteria, especially the diverse effects exerted by plant compounds on various virulence factors that are critical for pathogenicity inside the host. In addition, the potential effect of PDAs on gut microbiota is discussed. PMID:25298964

Upadhyaya, Indu; Kollanoor-Johny, Anup

2014-01-01

197

Sterol Profile for Natural Juices Authentification by GC-MS  

SciTech Connect

A GC-MS analytical method is described for some natural juices analysis. The fingerprint of sterols was used to characterize the natural juice. A rapid liquid-liquid extraction method was used. The sterols were separated on a Rtx-5MS capillary column, 15mx0.25mm, 0.25{mu}m film thickness, in a temperature program from 50 deg. C for 1 min, then ramped at 15 deg. C/min to 300 deg. C and held for 15 min. Identification of sterols and their patterns were used for juice characterization. The sterol profile is a useful approach for confirming the presence of juices of orange, grapefruit, pineapple and passion fruit in compounded beverages and for detecting of adulteration of fruit juices.

Culea, M. [Faculty of Physics, Babes-Bolyai University of Cluj-Napoca (Romania)

2007-04-23

198

Sterol Profile for Natural Juices Authentification by GC-MS  

NASA Astrophysics Data System (ADS)

A GC-MS analytical method is described for some natural juices analysis. The fingerprint of sterols was used to characterize the natural juice. A rapid liquid-liquid extraction method was used. The sterols were separated on a Rtx-5MS capillary column, 15m×0.25mm, 0.25?m film thickness, in a temperature program from 50°C for 1 min, then ramped at 15°C/min to 300°C and held for 15 min. Identification of sterols and their patterns were used for juice characterization. The sterol profile is a useful approach for confirming the presence of juices of orange, grapefruit, pineapple and passion fruit in compounded beverages and for detecting of adulteration of fruit juices.

Culea, M.

2007-04-01

199

Recent advances and safety issues of transgenic plant-derived vaccines.  

PubMed

Transgenic plant-derived vaccines comprise a new type of bioreactor that combines plant genetic engineering technology with an organism's immunological response. This combination can be considered as a bioreactor that is produced by introducing foreign genes into plants that elicit special immunogenicity when introduced into animals or human beings. In comparison with traditional vaccines, plant vaccines have some significant advantages, such as low cost, greater safety, and greater effectiveness. In a number of recent studies, antigen-specific proteins have been successfully expressed in various plant tissues and have even been tested in animals and human beings. Therefore, edible vaccines of transgenic plants have a bright future. This review begins with a discussion of the immune mechanism and expression systems for transgenic plant vaccines. Then, current advances in different transgenic plant vaccines will be analyzed, including vaccines against pathogenic viruses, bacteria, and eukaryotic parasites. In view of the low expression levels for antigens in plants, high-level expression strategies of foreign protein in transgenic plants are recommended. Finally, the existing safety problems in transgenic plant vaccines were put forward will be discussed along with a number of appropriate solutions that will hopefully lead to future clinical application of edible plant vaccines. PMID:23447052

Guan, Zheng-jun; Guo, Bin; Huo, Yan-lin; Guan, Zheng-ping; Dai, Jia-kun; Wei, Ya-hui

2013-04-01

200

Differences in the sterol composition of dominant Antarctic zooplankton.  

PubMed

The composition of free sterols was determined in Antarctic zooplankton species with various feeding behaviors. In the Southern Ocean, the dominant calanoid copepods Calanoides acutus, Calanus propinquus, Metridia gerlachei, and Euchaeta antarctica were investigated during different seasons and compared with the euphausiids Euphausia superba, E. crystallorophias, and Thysanoessa macrura. In addition, the Arctic copepods Calanus hyperboreus, C. glacialis, and C. finmarchicus were studied for comparison. Analyses were performed using gas chromatography and mass spectrometry. The zooplankton species exhibited a simple sterol content of up to six sterols. In the copepods, cholest-5-en-3beta-ol (22.1 to 60.5%, range of sample means), cholesta-5,24-dien-3beta-ol (22.3 to 45.2%), and cholesta-5,22E-dien-3beta-ol (4.3 to 33.4%) contributed most, while in euphausiids the sterol composition was less complex with cholest-5-en-3beta-ol always accounting for more than 75% of the total. Although sterols are membrane constituents and are expected not to vary considerably, differences in the abundance of sterols were observed between the species and the seasons. In herbivorous copepods, cholesta-5,24-dien-3beta-ol increased by a factor of 1.5 to about 45% during the main feeding period in summer; this sterol is a metabolic precursor of cholest-5-en-3beta-ol in the process of the dealkylation of dietary C-24 alkylated phytosterols. Cholest-5-en-3beta-ol decreased by the same proportion. Omnivorous and carnivorous copepods showed average levels of cholesta-5,24-dien-3beta-ol below 25%. These changes in sterol composition between copepod species seem to reflect their different feeding modes. PMID:10188596

Mühlebach, A; Albers, C; Kattner, G

1999-01-01

201

Use of Plant Viruses for Production of Plant-Derived Vaccines  

Microsoft Academic Search

Plants produce appropriately folded, post-translationally processed proteins that, as antigens, elicit efficacious immune responses in preclinical animal models and antigen-specific responses in humans. Plant-produced vaccine candidates have been produced using transgenic technologies and the utilization of plant viruses for the transient protein expression. The later approach has numerous advantages in recombinant protein production, including rapid protein expression and higher yields

Laurence K. Grill; Kenneth E. Palmer; Gregory P. Pogue

2005-01-01

202

SURVEY OF THE STEROL COMPOSITION OF THE MARINE DINOFLAGELLATES KARENIA BREVIS, KARENIA MIKIMOTOI, AND KARLODINIUM MICRUM: DISTRIBUTION OF STEROLS WITHIN OTHER MEMBERS OF THE CLASS DINOPHYCEAE  

EPA Science Inventory

The sterol composition of different marine microalgae was examined to determine the utility of sterols as biomarkers to distinguish members of various algal classes. For example, members of the class Dinophyceae possess certain 4-methyl sterols, such as dinosterol, which are rare...

203

N-Glycosylation Modification of Plant-Derived Virus-Like Particles: An Application in Vaccines  

PubMed Central

Plants have been developed as an alternative system to mammalian cells for production of recombinant prophylactic or therapeutic proteins for human and animal use. Effective plant expression systems for recombinant proteins have been established with the optimal combination of gene expression regulatory elements and control of posttranslational processing of recombinant glycoproteins. In plant, virus-like particles (VLPs), viral “empty shells” which maintain the same structural characteristics of virions but are genome-free, are considered extremely promising as vaccine platforms and therapeutic delivery systems. Unlike microbial fermentation, plants are capable of carrying out N-glycosylation as a posttranslational modification of glycoproteins. Recent advances in the glycoengineering in plant allow human-like glycomodification and optimization of desired glycan structures for enhancing safety and functionality of recombinant pharmaceutical glycoproteins. In this review, the current plant-derived VLP approaches are focused, and N-glycosylation and its in planta modifications are discussed. PMID:24971324

Jeon, Jae-Heung; Lee, Kyung Jin; Ko, Kisung

2014-01-01

204

Use of plant fatty acyl hydroxylases to produce hydroxylated fatty acids and derivatives in plants  

DOEpatents

The present invention relates to the identification of nucleic acid sequences and constructs, and methods related thereto, and the use of these sequences and constructs to produce genetically modified plants for the purpose of altering the composition of plant oils, waxes and related compounds. 35 figs.

Somerville, C.; Loo, F. van de

1998-09-01

205

Use of plant fatty acyl hydroxylases to produce hydroxylated fatty acids and derivatives in plants  

DOEpatents

The present invention relates to the identification of nucleic acid sequences and constructs, and methods related thereto, and the use of these sequences and constructs to produce genetically modified plants for the purpose of altering the composition of plant oils, waxes and related compounds. 35 figs.

Somerville, C.; Loo, F. van de

1997-09-16

206

Use of plant fatty acyl hydroxylases to produce hydroxylated fatty acids and derivatives in plants  

DOEpatents

The present invention relates to the identification of nucleic acid sequences and constructs, and methods related thereto, and the use of these sequences and constructs to produce genetically modified plants for the purpose of altering the composition of plant oils, waxes and related compounds.

Somerville, Chris (Portola Valley, CA); van de Loo, Frank (Lexington, KY)

2002-01-01

207

Use of plant fatty acyl hydroxylases to produce hydroxylated fatty acids and derivatives in plants  

DOEpatents

The present invention relates to the identification of nucleic acid sequences and constructs, and methods related thereto, and the use of these sequences and constructs to produce genetically modified plants for the purpose of altering the composition of plant oils, waxes and related compounds.

Somerville, Chris (Portola Valley, CA); van de Loo, Frank (Lexington, KY)

1997-01-01

208

Use of plant fatty acyl hydroxylases to produce hydroxylated fatty acids and derivatives in plants  

DOEpatents

The present invention relates to the identification of nucleic acid sequences and constructs, and methods related thereto, and the use of these sequences and constructs to produce genetically modified plants for the purpose of altering the composition of plant oils, waxes and related compounds.

Somerville, Chris (Portola Valley, CA); van de Loo, Frank (Lexington, KY)

1998-01-01

209

Terrestrial Plant-Derived Anticancer Agents and Plant Species Used in Anticancer Research  

Microsoft Academic Search

Cancer is a major cause of death and the number of new cases, as well as the number of individuals living with cancer, is expanding continuously. Due to the enormous propensity of plants that synthesize mixtures of structurally diverse bioactive compounds, the plant kingdom is potentially a very diverse source of chemical constituents with tumor cytotoxic activity. Despite the successful

Spiridon E. Kintzios

2006-01-01

210

Mythobotany, pharmacology, and chemistry of thujone-containing plants and derivatives  

Microsoft Academic Search

Thujone, C10H16O, is the primary constituent of essential oils derived from a variety of plants, including wormwood, Artemisia absinthium;\\u000a mugwort, Artemisia vulgaris; sage, Salvia officinalis; clary, Salvia sclarea; tansy, Tanacetum vulgare; and yellow cedar or\\u000a the tree of life, Thuja occidentalis. While oils derived from the individual species may vary in the modifying constituents\\u000a which they contain, the pharmacological effects

Michael Albert-Puleo

1978-01-01

211

Changes in Sterol Composition during Greening of Etiolated Barley Shoots 1  

PubMed Central

The following sterols were identified in barley shoots: stigmasterol, ?-sitosterol, campesterol, and cholesterol. The total sterol content of green and etiolated tissue was 2.84 and 3.20 milligrams per gram dry weight, respectively. The free sterols accounted for most of the difference in total sterol content. The sterol ester, sterol glycoside, and acylated sterol glycoside contents of green and etiolated barley shoots were essentially the same. Etiolated tissue had twice as much total ?-sitosterol as stigmasterol, while green tissue had equal amounts of these two sterols. The campesterol and cholesterol content was the same in green and etiolated tissue. This same sterol composition pattern held true for the free, glycosidic, and acylated glycosidic sterols; however, the sterol ester fraction had a completely different composition pattern. The esterified stigmasterol content was quite low in green and etiolated tissue, and campesterol was the second largest esterfied sterol component in etiolated tissue. Etiolated barley seedlings exposed to light had a shift in the ratio of free stigmasterol to ?-sitosterol in favor of stigmasterol; however, no correlation was observed between chlorophyll synthesis and shift in sterol composition. PMID:16657698

Bush, Parshall B.; Grunwald, C.; Davis, D. L.

1971-01-01

212

Determination of sterols, estrogens and inorganic ions in waste water and size-segregated aerosol particles emitted from waste water treatment  

Microsoft Academic Search

Concentrations of steroids and inorganic ions were measured in waste water of an aerated sand trap as well as in aerosol particles emitted from this tank at the waste water treatment plant (WWTP) of Bayreuth, Germany, in January and February 2003. The investigations comprised seven sterols, two estrogens, and several inorganic ions. Since an appropriate method for the determination of

Melanie Beck; Michael Radke

2006-01-01

213

Lignite-Derived Humic Acid Effect on Growth of Wheat Plants in Different Soils  

Microsoft Academic Search

Humic acid (HA), a fairly stable product of decomposed organic matter that consequently accumulates in ecological systems, enhances plant growth by chelating unavailable nutrients and buffering pH. We examined the effect of HA derived from lignite on growth and macronutrient uptake of wheat (Triticum aestivum L.) grown in earthen pots under greenhouse conditions. The soils used in the pot experiment

M. M. TAHIR; M. KHURSHID; M. Z. KHAN; M. K. ABBASI; M. H. KAZMI

2011-01-01

214

Plant-derived synergists of alarm pheromone from turnip aphid, Lipaphis (Hyadaphis) erysimi (Homoptera, Aphididae)  

Microsoft Academic Search

The turnip aphid,Lipaphis (Hyadaphis) erysimi, responds weakly to (E)-ß-farnesene, the main component of the alarm pheromone, but the response is substantially increased by incorporating plant-derived isothiocyanates, identified in aphid volatiles by coupled gas chromatography-single-cell recording.

G. W. Dawson; D. C. Griffiths; J. A. Pickett; L. J. Wadhams; Christine M. Woodcock

1987-01-01

215

Pestaloficiols A–E, bioactive cyclopropane derivatives from the plant endophytic fungus Pestalotiopsis fici  

Microsoft Academic Search

Pestaloficiols A–E (1–5), five new cyclopropane derivatives, have been isolated from cultures of the plant endophyte Pestalotiopsis fici. The structures of these compounds were determined by NMR spectroscopy, and the absolute configuration of 1 was assigned using the modified Mosher method. Compounds 1, 2, and 4 displayed inhibitory effects on HIV-1 replication in C8166 cells.

Ling Liu; Renrong Tian; Shuchun Liu; Xulin Chen; Liangdong Guo; Yongsheng Che

2008-01-01

216

Role of Plant-Derived Omega–3 Fatty Acids in Human Nutrition  

Microsoft Academic Search

An international workshop on the role of plant-derived omega–3 fatty acids in human nutrition took place in Milan on February 9, 2000. The meeting was sponsored by the Nutrition Foundation of Italy and was organized by its Scientific Director, Dr. Andrea Poli. It was attended by experts in polyunsaturated fatty acids and human lipid nutrition. This is the first meeting

Michael Crawford; Claudio Galli; Francesco Visioli; Serge Renaud; Artemis P. Simopoulos; Arthur A. Spector

2000-01-01

217

Fate of Octyl- and Nonylphenol Ethoxylates and Some Carboxylated Derivatives in Three American Wastewater Treatment Plants  

Technology Transfer Automated Retrieval System (TEKTRAN)

The fate of a comprehensive group of nonylphenol and octylphenol ethoxylates and several of their carboxylated derivatives was studied in three American wastewater treatment plants (WWTPs), two of which included advanced treatment. In spite of being located in three different metropolitan areas, wa...

218

A dietary test of putative deleterious sterols for the aphid Myzus persicae.  

PubMed

The aphid Myzus persicae displays high mortality on tobacco plants bearing a transgene which results in the accumulation of the ketosteroids cholestan-3-one and cholest-4-en-3-one in the phloem sap. To test whether the ketosteroids are the basis of the plant resistance to the aphids, M. persicae were reared on chemically-defined diets with different steroid contents at 0.1-10 µg ml(-1). Relative to sterol-free diet and dietary supplements of the two ketosteroids and two phytosterols, dietary cholesterol significantly extended aphid lifespan and increased fecundity at one or more dietary concentrations tested. Median lifespan was 50% lower on the diet supplemented with cholest-4-en-3-one than on the cholesterol-supplemented diet. Aphid feeding rate did not vary significantly across the treatments, indicative of no anti-feedant effect of any sterol/steroid. Aphids reared on diets containing equal amounts of cholesterol and cholest-4-en-3-one showed fecundity equivalent to aphids on diets containing only cholesterol. Aphids were reared on diets that reproduced the relative steroid abundance in the phloem sap of the control and modified tobacco plants, and their performance on the two diet formulations was broadly equivalent. We conclude that, at the concentrations tested, plant ketosteroids support weaker aphid performance than cholesterol, but do not cause acute toxicity to the aphids. In plants, the ketosteroids may act synergistically with plant factors absent from artificial diets but are unlikely to be solely responsible for resistance of modified tobacco plants. PMID:24465993

Bouvaine, Sophie; Faure, Marie-Line; Grebenok, Robert J; Behmer, Spencer T; Douglas, Angela E

2014-01-01

219

Derivative Analysis of AVIRIS Hyperspectral Data for the Detection of Plant Stress  

NASA Technical Reports Server (NTRS)

A remote sensing campaign was conducted over a U.S. Department of Agriculture test site at Shelton, Nebraska. The test field was set off in blocks that were differentially treated with nitrogen. Four replicates of 0-kg/ha to 200-kg/ha, in 50-kg/ha increments, were present. Low-altitude AVIRIS hyperspectral data were collected over the site in 224 spectral bands. Simultaneously, ground data were collected to support the airborne imagery. In an effort to evaluate published, derivative-based algorithms for the detection of plant stress, different derivative-based approaches were applied to the collected AVIRIS image cube. The results indicate that, given good quality hyperspectral imagery, derivative techniques compare favorably with simple, well known band ratio algorithms for detection of plant stress.

Estep, Lee; Berglund, Judith

2001-01-01

220

Effects of sterols on the development and aging of Caenorhabditis elegans.  

PubMed

Although Caenorhabditis elegans lacks several components of the de novo sterol biosynthetic pathway, it requires sterols as essential nutrients. Supplemental cholesterol undergoes extensive enzymatic modification in C. elegans to form certain sterols of unknown function. Since sterol metabolism in C. elegans differs from that in other species, such as mammals and yeast, it is important to examine how sterols regulate worm physiology. To examine the functions of sterols in C. elegans, a sterol-feeding experiment was carried out and several critical parameters, such as brood size, growth rate, and life span, were measured. In addition, the change in lipid distribution in C. elegans can be both qualitatively and quantitatively determined by various methods, including staining and chromatographic techniques. Taken together, the effects of sterols on C. elegans are very prominent and can be easily assessed using the techniques described here. PMID:19160668

Lee, Eun-Young; Jeong, Pan-Young; Kim, Sun-Young; Shim, Yhong-Hee; Chitwood, David J; Paik, Young-Ki

2009-01-01

221

A data mining approach to dinoflagellate clustering according to sterol composition: Correlations with evolutionary history.  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study examined the sterol compositions of 102 dinoflagellates (including several previously unexamined species) using clustering techniques as a means of determining the relatedness of the organisms. In addition, dinoflagellate sterol-based relationships were compared statistically to dinoflag...

222

Field assessment of plant derivative compounds for managing fungal soybean diseases.  

PubMed

Natural plant-derived compounds are currently being explored as alternatives for pest control in sustainable agriculture. This study explored the use of two compounds, sesamol and carbenoxolone, in the management of the fungal soybean disease charcoal rot (Macrophomina phaseolina). Previous studies have determined that sesamol and carbenoxolone compounds significantly inhibited fungal pathogen growth and plant disease in vitro. In order to assess the field efficacy of these compounds for fungal disease control, 2 years of field testing of these compounds have been conducted in southeast Kansas. Field treatments of the compounds sesamol and carbenoxolone at three concentrations, 0, 500 and 1000 microg/ml, were applied foliarly at four distinct plant developmental stages. Treatments were applied to plots in random triplicate array and the experiment was repeated during the 1998 and 1999 growing seasons. Disease assessments were based on visual disease ratings, plant mortality and soybean yield analysis. Data were recorded weekly for each treatment plot and statistically analysed using analysis of variance. Results indicate that sesamol and carbenoxolone treatments significantly decreased disease symptoms (11-12%) and plant mortality (24-28%) while significantly increasing soybean yields (18-38%). These results support that plant-derived compounds can have a significant impact on soybean disease management and yield under field conditions. PMID:11171257

Brooker, N L; Long, J H; Stephan, S M

2000-12-01

223

Sterols and sphingolipids: dynamic duo or partners in crime?  

PubMed

One manner in which eukaryotic cells respond to their environments is by optimizing the composition and proportions of sterols and sphingolipids in membranes. The physical association of the planar ring of sterols with the acyl chains of phospholipids, particularly sphingolipids, produces membrane micro-heterogeneity that is exploited to coordinate several crucial pathways. We hypothesize that these lipid molecules play an integrated role in human disease; when one of the partners is mis-regulated, pathology frequently ensues. Sterols and sphingolipid levels are not coordinated by the action of a single master regulator, however the cross-talk between their metabolic pathways is considerable. We describe our perspectives on the key components of synthesis, catabolism and transport of these lipid partners with an emphasis on evolutionarily conserved reactions that produce disease states when defective. PMID:20362613

Gulati, Sonia; Liu, Ying; Munkacsi, Andrew B; Wilcox, Lisa; Sturley, Stephen L

2010-10-01

224

The sterol composition of freshly harvested compared to stored seeds of rape, sunflower and poppy  

Microsoft Academic Search

The composition of the free sterols and the sterol esters of freshly harvested seeds of rape, sunflower and poppy was compared\\u000a to that of stored seeds. The sterol composition of rapeseed was not changed during storage, whereas in sunflower seed the\\u000a free sterols had less of ?5-avenasterol and ?7-stigmastenol in ten-month-old seeds compared to fresh seeds. The greatest relative\\u000a changes

A. Johansson; L.-Ĺ. Appelqvist

1979-01-01

225

Sterol Uptake in Saccharomyces cerevisiae Heme Auxotrophic Mutants Is Affected by Ergosterol and Oleate but Not by Palmitoleate or by Sterol Esterification  

PubMed Central

The relationship between sterol uptake and heme competence in two yeast strains impaired in heme synthesis, namely, G204 and H12-6A, was analyzed. To evaluate heme availability, a heterologous 17?-hydroxylase cytochrome P-450 cDNA (P-450c17) was expressed in these strains, and its activity was measured in vivo. Heme deficiency in G204 led to accumulation of squalene and lethality. The heterologous cytochrome P-450 was inactive in this strain. The leaky H12-6A strain presented a slightly modified sterol content compared to that for the wild type, and the P-450c17 recovered partial activity. By analyzing sterol transfer on nongrowing cells, it was shown that the cells were permeable toward exogenous cholesterol when they were depleted of endogenous sterols, which was the case for G204 but not for H12-6A. It was concluded that the fully blocked heme mutant (G204) replenishes its diminishing endogenous sterol levels during growth by replacement with sterol from the outside medium. Endogenous sterol biosynthesis appears to be the primary factor capable of excluding exogenous sterol. Oleate but not palmitoleate was identified as a component that reduced but did not prevent sterol transfer. Sterol transfer was only slightly affected by a lack of esterification. It is described herein how avoidance of the potential cytotoxicity of the early intermediates of the mevalonate pathway could be achieved by a secondary heme mutation in erg auxotrophs. PMID:9537392

Ness, Frédérique; Achstetter, Tilman; Duport, Catherine; Karst, Francis; Spagnoli, Roberto; Degryse, Eric

1998-01-01

226

Annual Variation in the Effect of Red Light on Sterol Biosynthesis in Digitalis purpurea L.  

PubMed

The effect of varying sequences of red and far red light on sterol biosynthesis in etiolated seedlings of Digitalis purpurea L. was examined. Red light caused a marked increase in the amounts of free and glycosidic sterols and a small decrease in esterified sterols during the first 4 hours after illumination. Far red light elicited the same response but to a lesser degree. Exposure to red followed by far red light or the reverse caused little or no increase in the amounts of free and glycosidic sterols. The magnitude of the increase in the amounts of sterols varied, depending upon the season in which the experiments were performed. The largest increments were obtained during the summer and fall, whereas the smallest were observed during the winter and spring. Correlation of these data with previous observations of an annual cycle in the sterol content of Digitalis seedlings showed that the maximum stimulation in sterol biosynthesis occurs when the endogenous level of sterols is minimal.Sterol monoglycosides, acylmonoglycosides, and an unidentified sterol conjugate from the lipid extracts were quantitated. Changes in conjugated sterol content were related to the particular light conditions of each experiment. The results are discussed in terms of physiological cycles and the possible influence of hormones upon the control of sterol biosynthesis in Digitalis. PMID:16660620

Jacobsohn, M K

1978-12-01

227

De novo production of the plant-derived alkaloid strictosidine in yeast  

PubMed Central

The monoterpene indole alkaloids are a large group of plant-derived specialized metabolites, many of which have valuable pharmaceutical or biological activity. There are ?3,000 monoterpene indole alkaloids produced by thousands of plant species in numerous families. The diverse chemical structures found in this metabolite class originate from strictosidine, which is the last common biosynthetic intermediate for all monoterpene indole alkaloid enzymatic pathways. Reconstitution of biosynthetic pathways in a heterologous host is a promising strategy for rapid and inexpensive production of complex molecules that are found in plants. Here, we demonstrate how strictosidine can be produced de novo in a Saccharomyces cerevisiae host from 14 known monoterpene indole alkaloid pathway genes, along with an additional seven genes and three gene deletions that enhance secondary metabolism. This system provides an important resource for developing the production of more complex plant-derived alkaloids, engineering of nonnatural derivatives, identification of bottlenecks in monoterpene indole alkaloid biosynthesis, and discovery of new pathway genes in a convenient yeast host. PMID:25675512

Brown, Stephanie; Clastre, Marc; Courdavault, Vincent; O’Connor, Sarah E.

2015-01-01

228

De novo production of the plant-derived alkaloid strictosidine in yeast.  

PubMed

The monoterpene indole alkaloids are a large group of plant-derived specialized metabolites, many of which have valuable pharmaceutical or biological activity. There are ?3,000 monoterpene indole alkaloids produced by thousands of plant species in numerous families. The diverse chemical structures found in this metabolite class originate from strictosidine, which is the last common biosynthetic intermediate for all monoterpene indole alkaloid enzymatic pathways. Reconstitution of biosynthetic pathways in a heterologous host is a promising strategy for rapid and inexpensive production of complex molecules that are found in plants. Here, we demonstrate how strictosidine can be produced de novo in a Saccharomyces cerevisiae host from 14 known monoterpene indole alkaloid pathway genes, along with an additional seven genes and three gene deletions that enhance secondary metabolism. This system provides an important resource for developing the production of more complex plant-derived alkaloids, engineering of nonnatural derivatives, identification of bottlenecks in monoterpene indole alkaloid biosynthesis, and discovery of new pathway genes in a convenient yeast host. PMID:25675512

Brown, Stephanie; Clastre, Marc; Courdavault, Vincent; O'Connor, Sarah E

2015-03-17

229

Screening, isolation and optimization of anti–white spot syndrome virus drug derived from marine plants  

PubMed Central

Objective To screen, isolate and optimize anti-white spot syndrome virus (WSSV) drug derived from various marine floral ecosystems and to evaluate the efficacy of the same in host–pathogen interaction model. Methods Thirty species of marine plants were subjected to Soxhlet extraction using water, ethanol, methanol and hexane as solvents. The 120 plant isolates thus obtained were screened for their in vivo anti-WSSV property in Litopenaeus vannamei. By means of chemical processes, the purified anti-WSSV plant isolate, MP07X was derived. The drug was optimized at various concentrations. Viral and immune genes were analysed using reverse transcriptase PCR to confirm the potency of the drug. Results Nine plant isolates exhibited significant survivability in host. The drug MP07X thus formulated showing 85% survivability in host. The surviving shrimps were nested PCR negative at the end of the 15 d experimentation. The lowest concentration of MP07X required intramuscularly for virucidal property was 10 mg/mL. The oral dosage of 1?000 mg/kg body weight/day survived at the rate of 85%. Neither VP28 nor ie 1 was expressed in the test samples at 42nd hour and 84th hour post viral infection. Conclusions The drug MP07X derived from Rhizophora mucronata is a potent anti-WSSV drug. PMID:25183065

Chakraborty, Somnath; Ghosh, Upasana; Balasubramanian, Thangavel; Das, Punyabrata

2014-01-01

230

Protein Mediators of Sterol Transport Across Intestinal Brush Border Membrane  

PubMed Central

Dysregulation of cholesterol balance contributes significantly to atherosclerotic cardiovascular disease (ASCVD), the leading cause of death in the United States. The intestine has the unique capability to act as a gatekeeper for entry of cholesterol into the body, and inhibition of intestinal cholesterol absorption is now widely regarded as an attractive non-statin therapeutic strategy for ASCVD prevention. In this chapter we discuss the current state of knowledge regarding sterol transport across the intestinal brush border membrane. The purpose of this work is to summarize substantial progress made in the last decade in regards to protein-mediated sterol trafficking, and to discuss this in the context of human disease. PMID:20213550

Brown, J. Mark; Yu, Liqing

2012-01-01

231

Different bacterial populations associated with the roots and rhizosphere of rice incorporate plant-derived carbon.  

PubMed

Microorganisms associated with the roots of plants have an important function in plant growth and in soil carbon sequestration. Rice cultivation is the second largest anthropogenic source of atmospheric CH4, which is a significant greenhouse gas. Up to 60% of fixed carbon formed by photosynthesis in plants is transported below ground, much of it as root exudates that are consumed by microorganisms. A stable isotope probing (SIP) approach was used to identify microorganisms using plant carbon in association with the roots and rhizosphere of rice plants. Rice plants grown in Italian paddy soil were labeled with (13)CO2 for 10 days. RNA was extracted from root material and rhizosphere soil and subjected to cesium gradient centrifugation followed by 16S rRNA amplicon pyrosequencing to identify microorganisms enriched with (13)C. Thirty operational taxonomic units (OTUs) were labeled and mostly corresponded to Proteobacteria (13 OTUs) and Verrucomicrobia (8 OTUs). These OTUs were affiliated with the Alphaproteobacteria, Betaproteobacteria, and Deltaproteobacteria classes of Proteobacteria and the "Spartobacteria" and Opitutae classes of Verrucomicrobia. In general, different bacterial groups were labeled in the root and rhizosphere, reflecting different physicochemical characteristics of these locations. The labeled OTUs in the root compartment corresponded to a greater proportion of the 16S rRNA sequences (?20%) than did those in the rhizosphere (?4%), indicating that a proportion of the active microbial community on the roots greater than that in the rhizosphere incorporated plant-derived carbon within the time frame of the experiment. PMID:25616793

Hernández, Marcela; Dumont, Marc G; Yuan, Quan; Conrad, Ralf

2015-03-15

232

Structural and Functional Analyses of a Sterol Carrier Protein in Spodoptera litura  

PubMed Central

Backgrounds In insects, cholesterol is one of the membrane components in cells and a precursor of ecdysteroid biosynthesis. Because insects lack two key enzymes, squalene synthase and lanosterol synthase, in the cholesterol biosynthesis pathway, they cannot autonomously synthesize cholesterol de novo from simple compounds and therefore have to obtain sterols from their diet. Sterol carrier protein (SCP) is a cholesterol-binding protein responsible for cholesterol absorption and transport. Results In this study, a model of the three-dimensional structure of SlSCPx-2 in Spodoptera litura, a destructive polyphagous agricultural pest insect in tropical and subtropical areas, was constructed. Docking of sterol and fatty acid ligands to SlSCPx-2 and ANS fluorescent replacement assay showed that SlSCPx-2 was able to bind with relatively high affinities to cholesterol, stearic acid, linoleic acid, stigmasterol, oleic acid, palmitic acid and arachidonate, implying that SlSCPx may play an important role in absorption and transport of these cholesterol and fatty acids from host plants. Site-directed mutation assay of SlSCPx-2 suggests that amino acid residues F53, W66, F89, F110, I115, T128 and Q131 are critical for the ligand-binding activity of the SlSCPx-2 protein. Virtual ligand screening resulted in identification of several lead compounds which are potential inhibitors of SlSCPx-2. Bioassay for inhibitory effect of five selected compounds showed that AH-487/41731687, AG-664/14117324, AG-205/36813059 and AG-205/07775053 inhibited the growth of S. litura larvae. Conclusions Compounds AH-487/41731687, AG-664/14117324, AG-205/36813059 and AG-205/07775053 selected based on structural modeling showed binding affinity to SlSCPx-2 protein and inhibitory effect on the growth of S. litura larvae. PMID:24454688

Xu, Rui; Zheng, Sichun; He, Hongwu; Wan, Jian; Feng, Qili

2014-01-01

233

Lipase-mediated synthesis of water-soluble plant stanol derivatives in tert-butanol.  

PubMed

The effects of solvents with different log P values, and of lipases on the synthesis of water-soluble plant stanol derivatives were investigated. Results showed that conversion in solvents with log P<0.37 was mainly controlled by the hydrophobicity of the solvent and subsequent complete or partial deactivation of the enzyme. The solubility of substrate was the leading factor for the conversion in solvents with log P>0.37. Lipozyme RM IM and tert-butanol was the most suitable biocatalyst and solvent, respectively. The highest yield (>51%) of plant stanyl sorbitol succinate was obtained under the selected conditions: 50 ?mol/mL plant stanyl hemisuccinate, 1:3 molar ratio of plant stanyl hemisuccinate to d-sorbitol, 80 mg/mL 3 Ĺ molecular sieves and 100mg/mL Lipozyme RM IM in tert-butanol, 150 r/min and 55 °C. Fourier transform infrared spectroscopy, mass spectroscopy and nuclear magnetic resonance spectroscopy were adopted to determine the structure of product, suggesting that water-soluble plant stanol derivatives were successfully synthesized. PMID:22464062

He, Wen-Sen; Li, Jing-Jing; Pan, Xiao-Xia; Zhou, Yang; Jia, Cheng-Sheng; Zhang, Xiao-Ming; Feng, Biao

2012-06-01

234

Presence of phthalate derivatives in the essential oils of a medicinal plant Achillea tenuifolia.  

PubMed

BackgroundPhthalate, esters of phthalic acid, are mainly applied as plasticizers and cause several human health and environment hazards. The essential oils of Achillea species have attracted a great concern, since several biological activities have been reported from varieties of these medicinal species. On the other side, due to the problems regarding the waste disposal in developing countries, phthalate derivatives can easily release from waste disposal to the water and soil resulting in probable absorption and accumulation by medicinal and dietary plants. As a matter of fact, although the toxicity of phthalate derivatives in human is well-known, food crops and medicinal plants have been exposing to phthalates that can be detected in their extracts and essential oils. Achillea tenuifolia (Compositea) is one of these herbaceous plants with traditional applications which widely growing in Iran.FindingThe plant root was subjected to hydro-distillation for 4 h using Clevenger type apparatus to obtain its essential oil before and after acid treatment. Both of the hydro-distilled essential oils were analysed by GC-MS method resulted in recognition of their constituent. Phthalate contamination as (1, 2-benzenedicarboxylic acid, bis (2-methylpropyl) ester (5.4%) and phthalic acid (4.5%), were identified in the first and second extracted oils, respectively.ConclusionAs a warning, due to the potential role of phthalates to cause reproductive toxicity, disturb of endocrine system and causing cancers, medicinal plants have to be considered through quality control for detection of these compounds. PMID:25429772

Manayi, Azadeh; Kurepaz-Mahmoodabadi, Mahdieh; Gohari, Ahmad R; Ajani, Yousef; Saeidnia, Soodabeh

2014-11-28

235

Strategies to protect crop plants against viruses: pathogen-derived resistance blossoms.  

PubMed Central

Since 1986, the ability to confer resistance against an otherwise devastating virus by introducing a single pathogen-derived or virus-targeted sequence into the DNA of a potential host plant has had a marked influence on much of the research effort, focus, and short-term objectives of plant virologists throughout the world. The vast literature on coat protein-mediated protection, for example, attests to our fascination for unraveling fundamental molecular mechanism(s), our (vain) search for a unifying hypothesis, our pragmatic interest in commercially exploitable opportunities for crop protection, and our ingenuity in manipulating transgene constructions to broaden their utility and reduce real or perceived environmental risk issues. Other single dominant, pathogen-derived plant resistance genes have recently been discovered from a wide variety of viruses and are operative in an ever-increasing range of plant species. Additional candidates seem limited only by the effort invested in experimentation and by our ingenuity and imagination. This review attempts to consider, in a critical way, the current state of the art, some exceptions, and some proposed rules. The final impression, from all the case evidence considered, is that normal virus replication requires a subtle blend of host- and virus-coded proteins, present in critical relative concentrations and at specific times and places. Any unregulated superimposition of interfering protein or nucleic acid species can, therefore, result in an apparently virus-resistant plant phenotype. PMID:8475051

Wilson, T M

1993-01-01

236

Screening, isolation and optimization of anti–white spot syndrome virus drug derived from terrestrial plants  

PubMed Central

Objective To screen, isolate and optimize anti-white spot syndrome virus (WSSV) drug derived from various terrestrial plants and to evaluate the efficacy of the same in host–pathogen interaction model. Methods Thirty plants were subjected to Soxhlet extraction using water, ethanol, methanol and hexane as solvents. The 120 plant isolates thus obtained were screened for their in vivo anti–WSSV property in Litopenaeus vannamei. The best anti–WSSV plant isolate, TP22C was isolated and further analyzed. The drug was optimized at various concentrations. Viral and immune genes were analysed using reverse transcriptase PCR to confirm the potency of the drug. Results Seven plant isolates exhibited significant survivability in host. The drug TP22C thus formulated showed 86% survivability in host. The surviving shrimps were nested PCR negative at the end of the 15 d experimentation. The lowest concentration of TP22C required intramuscularly for virucidal property was 10 mg/mL. The oral dosage of 750 mg/kg body weight/day survived at the rate of 86%. Neither VP28 nor ie 1 was expressed in the test samples at 42nd hour and 84th hour post viral infection. Conclusions The drug TP22C derived from Momordica charantia is a potent anti-white spot syndrome virus drug. PMID:25183066

Ghosh, Upasana; Chakraborty, Somnath; Balasubramanian, Thangavel; Das, Punyabrata

2014-01-01

237

Protoplast-derived streptomycin resistant plants of the forage legume Onobrychis viciifolia Scop. (sainfoin).  

PubMed

Approximately 10(6) protoplast-derived cell colonies of sainfoin were stressed with streptomycin and two resistant colonies were recovered. Plants regenerated from these colonies could be recallused on streptomycin-containing medium three years after growth in the absence of the antibiotic.Ultrastructural studies showed cells of resistant callus grown in the presence of streptomycin to contain chloroplasts with internal thykaloids and grana. Such mutant plants should be useful in designing biochemical selection schemes to recover somatic hybrids and cybrids. PMID:24248400

Hamill, J D; Ahuja, P S; Davey, M R; Cocking, E C

1986-12-01

238

Virtual screening of plant derived compounds for aldose reductase inhibition using molecular docking.  

PubMed

The role of the aldose reductase in type 2 diabetes is widely described. Therefore, it is of interest to identify plant derived compounds to inhibit its activity. We studied the protein-ligand interaction of 267 compounds from different parts of seven plants (Allium sativum, Coriandrum sativum, Dacus carota, Murrayyakoneigii, Eucalyptus, Calendula officinalis and Lycopersicon esculentum) with aldose reductase as the target protein. Molecular docking and re-scoring of top ten compounds (using GOLD, AutoDock Vina, eHiTS, PatchDock and MEDock) followed by rank-sum technique identified compound allium38 with high binding affinity for aldose reductase. PMID:23275691

Muppalaneni, Naresh Babu; Rao, Allam Appa

2012-01-01

239

Food plant derived disease tolerance and resistance in a natural butterfly-plant-parasite interactions.  

PubMed

Organisms can protect themselves against parasite-induced fitness costs through resistance or tolerance. Resistance includes mechanisms that prevent infection or limit parasite growth while tolerance alleviates the fitness costs from parasitism without limiting infection. Although tolerance and resistance affect host-parasite coevolution in fundamentally different ways, tolerance has often been ignored in animal-parasite systems. Where it has been studied, tolerance has been assumed to be a genetic mechanism, unaffected by the host environment. Here we studied the effects of host ecology on tolerance and resistance to infection by rearing monarch butterflies on 12 different species of milkweed food plants and infecting them with a naturally occurring protozoan parasite. Our results show that monarch butterflies experience different levels of tolerance to parasitism depending on the species of milkweed that they feed on, with some species providing over twofold greater tolerance than other milkweed species. Resistance was also affected by milkweed species, but there was no relationship between milkweed-conferred resistance and tolerance. Chemical analysis suggests that infected monarchs obtain highest fitness when reared on milkweeds with an intermediate concentration, diversity, and polarity of toxic secondary plant chemicals known as cardenolides. Our results demonstrate that environmental factors-such as interacting species in ecological food webs-are important drivers of disease tolerance. PMID:23106703

Sternberg, Eleanore D; Lefčvre, Thierry; Li, James; de Castillejo, Carlos Lopez Fernandez; Li, Hui; Hunter, Mark D; de Roode, Jacobus C

2012-11-01

240

Occurrence of squalene and sterols in Cellulomonas dehydrogenans (Arnaudi 1942) comb. nov. Hester 1971.  

PubMed Central

The neutral lipid fraction of the photochromogenic, coryneform bacterium Cellulomonas dehydrogenans (Arnaudi 1942) comb. nov. contains the sterol precursor squalene and at least two sterols, cholesterol and beta-sitosterol. The compounds were characterized by mass spectrometry and combination gas-liquid chromatography--mass spectrometry. De novo sterol biosynthetic ability was shown from incorporation of 14C from D-[U-14C]glucose into squalene and the sterol fraction. The squalene concentration approximated 0.002 to 0.005% of the total dry cell weight, and the sterols approximated 0.03 to 0.05%. Images PMID:101527

Weeks, O B; Francesconi, M D

1978-01-01

241

Pestalofones A–E, bioactive cyclohexanone derivatives from the plant endophytic fungus Pestalotiopsis fici  

Microsoft Academic Search

Pestalofones A–E (1–5), five new cyclohexanone derivatives, have been isolated from cultures of the plant endophytic fungus Pestalotiopsis fici, along with the known compounds, isosulochrin (6), isosulochrin dehydrate (7), and iso-A82775C (8). The structures of 1–5 were determined by NMR spectroscopy, and the absolute configuration of 1 was assigned using the modified Mosher method. Compounds 1, 2, and 5 displayed

Ling Liu; Shuchun Liu; Xulin Chen; Liangdong Guo; Yongsheng Che

2009-01-01

242

Regeneration of protoplast-derived green plants of Kentucky blue grass ( Poa pratensis L.)  

Microsoft Academic Search

Green plants were repeatedly regenerated from suspension-derived protoplasts of Kentucky blue grass (Poa pratensis L.) cv. “Geronimo”. One suspension was capable of donating competent protoplasts during long-term culture i. e. 10–16 months after its establishment. The plating efficiency of the protoplasts from three different suspension lines varied from 0.004% in the lowest up to 1.5% in the highest responding line,

Kirsten Annette Nielsen; Else Larsen; Elisabeth Knudsen

1993-01-01

243

Utilization of beet molasses for sterol production by some moulds.  

PubMed

Different moulds were cultivated in beet molasses (BM)-containing medium. Penicillium crustosum Thom was superior to the other moulds in total sterols production (4% on dry weight basis), efficiency of convertibility of the BM sugars to sterols (2%), total lipids (19.4%) and unsaponified lipids (13.4%). The treatment of BM with H2SO4- followed by centrifugation allowed maximum fermentation yields. The highest unsaponified lipids (16.5%) and total sterols level (7.4%) were obtained with a medium composed of (g/1): NaNO3, 3; K2HPO4, 3; MgSO4.7H2O, 1.5; K2SO4, 0.11; ZnSO4.7H2O, 0.05; FeCl3.6H2O, 0.16; H2SO4-treated BM, 60. Maximal sterol yields (8.4%) and high growth rate were achieved at the accelerated growth phase (8 days old cultures), when the initial pH value of the medium was adjusted to 7.0. PMID:2206469

Ghanem, K M; Ghanem, N B; el-Refai, A H

1990-06-01

244

Incorporation of Sterols into Cells Using Cholesterol/Cyclodextrin Complexes  

E-print Network

Incorporation of Sterols into Cells Using Cholesterol/Cyclodextrin Complexes Reagents NeededH 7.2 Cholesterol/Cyclodextrin Complexes (6.8 mM cholesterol in 70 mM cyclodextrin) Phosphate to DME. Warm to 37° in the tissue culture incubator. Use 3 ml DME per 60 mm dish. 2 . Add cholesterol

Pike, Linda J.

245

Seasonal variation of vitamin and sterol content of chironomidae larvae.  

PubMed

In the present study, seasonal variation of vitamin and sterol content of Chironomidae larvae were determined by using HPLC. As the result of vitamin analysis, we found alpha-tocopherol, retinol, K1, K2, D2 and D3. When the seasonal variation of vitamin groups were compared, a significant increase was observed in vitamin K1, K2, D2 and alpha-tocopherol in all seasons. A significant increase was observed in vitamin D3 in spring. And also vitamin A level high in autumn and winter, alpha-tocopherol level was significantly high among vitamins. When vitamin groups were compared statistically, differences were detected between seasons (p < 0.001). Analyzing the content of sterol, we found ergosterol, cholesterol, stigmasterol and beta-sitosterol in all seasons. Cholesterol level was found to be significantly high in sterols. When sterol contents were compared statistically, differences were detected between seasons (p < 0.001). In conclusion, the reasons for these differences are larval development feature and the variety of food in different seasons. PMID:24511704

Kara, Tuba

2013-11-15

246

ORIGINAL PAPER Relationships between sterol/phospholipid composition  

E-print Network

such as passive and active drug transport have been shown to also play a significant role in therapeutic failures as in passive drug transport through cell mem- branes or indirectly as in active drug transport due to effluxORIGINAL PAPER Relationships between sterol/phospholipid composition and xenobiotic transport

Boyer, Edmond

247

INHIBITION OF STEROL METABOLISM IN CAENORHABDITIS ELEGANS BY AY-9944  

Technology Transfer Automated Retrieval System (TEKTRAN)

Caenorhabditis elegans and some other nematodes are capable of attaching a methyl group to the nucleus of sterols at the C-4 position. In C. elegans, 4-methylcholest-8(14)-enol is the most abundant 4-methylsterol produced, and smaller quantities of 4-methylcholest-7-enol also occur. The purpose of...

248

Recombinant plant-derived pharmaceutical proteins: current technical and economic bottlenecks.  

PubMed

Molecular pharming is a cost-effective platform for the production of recombinant proteins in plants. Although the biopharmaceutical industry still relies on a small number of standardized fermentation-based technologies for the production of recombinant proteins there is now a greater awareness of the advantages of molecular pharming particularly in niche markets. Here we discuss some of the technical, economic and regulatory barriers that constrain the clinical development and commercialization of plant-derived pharmaceutical proteins. We also discuss strategies to increase productivity and product quality/homogeneity. The advantages of whole plants should be welcomed by the industry because this will help to reduce the cost of goods and therefore expand the biopharmaceutical market into untapped sectors. PMID:25048244

Sabalza, Maite; Christou, Paul; Capell, Teresa

2014-12-01

249

Precise marker excision system using an animal-derived piggyBac transposon in plants  

PubMed Central

Accurate and effective positive marker excision is indispensable for the introduction of desired mutations into the plant genome via gene targeting (GT) using a positive/negative counter selection system. In mammals, the moth-derived piggyBac transposon system has been exploited successfully to eliminate a selectable marker from a GT locus without leaving a footprint. Here, we present evidence that the piggyBac transposon also functions in plant cells. To demonstrate the use of the piggyBac transposon for effective marker excision in plants, we designed a transposition assay system that allows the piggyBac transposition to be visualized as emerald luciferase (Eluc) luminescence in rice cells. The Eluc signal derived from piggyBac excision was observed in hyperactive piggyBac transposase-expressing rice calli. Polymerase chain reaction, Southern blot analyses and sequencing revealed the efficient and precise transposition of piggyBac in these calli. Furthermore, we have demonstrated the excision of a selection marker from a reporter locus in T0 plants without concomitant re-integration of the transposon and at a high frequency (44.0% of excision events), even in the absence of negative selection. PMID:24164672

Nishizawa-Yokoi, Ayako; Endo, Masaki; Osakabe, Keishi; Saika, Hiroaki; Toki, Seiichi

2014-01-01

250

Effect of Altered Sterol Composition on Growth Characteristics of Saccharomyces cerevisiae  

PubMed Central

The function of sterols in mitochondrial structures of yeast was examined. Sterol mutant strains were employed to examine the effects of altered sterolic content on optimal and permissive growth temperatures in respiring and fermenting cultures. Although fermentative growth was unaffected by sterol composition, a definite decrease in both the optimal and the permissive growth temperatures of respiring cultures was observed when ergosterol was replaced by ?8(9), 22-ergostadiene-3?-ol. In vitro studies showed a similar decrease in membrane phase transition temperatures of the mitochondrial enzyme S-adenosylmethionine: ?24-sterol methyltransferase in the mutant strains. Increased sterol and methyltransferase levels were detected in strains incapable of synthesizing ergosterol. A possible control function governing sterol synthesis is proposed for ergosterol. PMID:4616948

Thompson, E. D.; Parks, L. W.

1974-01-01

251

A review on plant-derived natural products and their analogs with anti-tumor activity  

PubMed Central

Traditional medicines, including Chinese herbal formulations, can serve as the source of potential new drugs, and initial research focuses on the isolation of bioactive lead compound(s). The development of novel plant-derived natural products and their analogs for anticancer activity details efforts to synthesize new derivatives based on bioactivity- and mechanism of action-directed isolation and characterization coupled with rational drug design - based modification. Also, the anticancer activity of certain natural products and their analogs can be enhanced by synthesizing new derivatives based on active pharmacophore models; drug resistance and solubility and metabolic limitations can be overcome by appropriate molecular modifications; and new biological properties or mechanisms of action can be added by combining other functional groups or molecules. Preclinical screening for in vitro human cell line panels and selected in vivo xenograft testing then identifies the most promising drug development targets. PMID:21279166

Dholwani, K.K.; Saluja, A.K.; Gupta, A.R.; Shah, D.R.

2008-01-01

252

Methodological considerations for the harmonization of non-cholesterol sterol bio-analysis.  

PubMed

Non-cholesterol sterols (NCS) are used as surrogate markers of cholesterol metabolism which can be measured from a single blood sample. Cholesterol precursors are used as markers of endogenous cholesterol synthesis and plant sterols are used as markers of cholesterol absorption. However, most aspects of NCS analysis show wide variability among researchers within the area of biomedical research. This variability in methodology is a significant contributor to variation between reported NCS values and hampers the confidence in comparing NCS values across different research groups, as well as the ability to conduct meta-analyses. This paper summarizes the considerations and conclusions of a workshop where academic and industrial experts met to discuss NCS measurement. Highlighted is why each step in the analysis of NCS merits critical consideration, with the hopes of moving toward more standardized and comparable NCS analysis methodologies. Alkaline hydrolysis and liquid-liquid extraction of NCS followed by parallel detection on GC-FID and GC-MS is proposed as an ideal methodology for the bio-analysis of NCS. Furthermore the importance of cross-comparison or round robin testing between various groups who measure NCS is critical to the standardization of NCS measurement. PMID:24674990

Mackay, Dylan S; Jones, Peter J H; Myrie, Semone B; Plat, Jogchum; Lütjohann, Dieter

2014-04-15

253

The lipids of the common house cricket,Acheta domesticus L. III. Sterols.  

PubMed

Sterols constitute 1.95% of the total extractable lipids ofAcheta domesticus L., of which 18% are esterified. The free sterols consist of cholestane-3beta-ol (0.5%), Delta(5)-cholestene-3beta-ol (83.5%), Delta(7)-cholestene-3beta-ol (2.3%) Delta(5,7)-cholestadiene-3beta-ol (3%), Delta(5,22)-cholestadiene-3beta-ol (4%), Delta(5,7,22)-cholestatriene-3beta-ol (0.2%), campestane-3beta-ol (0.03%), Delta(5)-campestene-3beta-ol (1.0%), Delta(7)-campestene-3beta-ol (trace), Delta(5,7)-campestadiene-3beta-ol (0.2%), stigmastane-3beta-ol (0.09%), Delta(5)-stigmastene-3beta-ol (2.1%), Delta(7)-stigmastene-3beta-ol (0.04%), Delta(5,7)-stigmastadiene-3beta-ol (0.4%), Delta(5,22)-stigmastadiene-3betaol (0.1%). The same sterols are present in the esterified sterol fraction. Delta(7)-Sterols and Delta(5,7)-sterols are present in significantly larger amounts in the esterified fraction than in the free sterol fraction. By a comparison with the sterols of the cricket food, it is clear thatA. domesticus is capable of removing methyl and ethyl groups from C-24 of sterols of the campestane and stigmastane type. The ability to introduce a Delta(7) double bond into saturated and Delta(5)-sterols is indicated, and it is suggested that Delta(7)-sterols of the C(27), C(28), and C(29) sterol series may be intermediates in the conversion of Delta(5)-sterols to Delta(5,7)-sterols. PMID:17805866

Martin, M M; Carls, G A

1968-05-01

254

Sterols and triterpene diols in olive oil as indicators of variety and degree of ripening.  

PubMed

Sterols and triterpene diols in olive oil as indicators of variety and degree of ripening derived from three olive varieties and produced at three different harvesting periods were studied. In order to test the stability of the proposed indicators, oils obtained were stored for 12 months at three different temperatures. Thirty-six samples in total were subjected to GC analysis and results were processed by multivariate chemometric methods (MANOVA, PCA, and SLDA). Campesterol, ?-sitosterol, ?(7)-campesterol/?(5,24)-stigmastadienol, clerosterol, uvaol, and campestanol/?(7)-avenasterol were established as the indicators of variety of fresh oils, while when stored oils were included in the model, the final three compounds were substituted by 24-methylene-cholesterol/stigmasterol. The most important variables for differentiating fresh oils according to degree of ripening were ?(7)-campesterol/?-sitosterol, uvaol/stigmasterol, clerosterol/?(5)-avenasterol and sitostanol/uvaol, while stored oils were differentiated by campestanol/stigmasterol, erythrodiol, stigmasterol/?(7)-campesterol, ?(5)-avenasterol, 24-methylene-cholesterol/?-sitosterol and 24-methylene-cholesterol. Results demonstrated that sterols and triterpene diols can be used as indicators of variety and degree of ripening among virgin olive oils. PMID:23017420

Luki?, Marina; Luki?, Igor; Krapac, Marin; Sladonja, Barbara; Piližota, Vlasta

2013-01-01

255

Biostimulant action of a plant-derived protein hydrolysate produced through enzymatic hydrolysis.  

PubMed

The aim of this study was to evaluate the biostimulant action (hormone like activity, nitrogen uptake, and growth stimulation) of a plant-derived protein hydrolysate by means of two laboratory bioassays: a corn (Zea mays L.) coleoptile elongation rate test (Experiment 1), a rooting test on tomato cuttings (Experiment 2); and two greenhouse experiments: a dwarf pea (Pisum sativum L.) growth test (Experiment 3), and a tomato (Solanum lycopersicum L.) nitrogen uptake trial (Experiment 4). Protein hydrolysate treatments of corn caused an increase in coleoptile elongation rate when compared to the control, in a dose-dependent fashion, with no significant differences between the concentrations 0.75, 1.5, and 3.0 ml/L, and inodole-3-acetic acid treatment. The auxin-like effect of the protein hydrolysate on corn has been also observed in the rooting experiment of tomato cuttings. The shoot, root dry weight, root length, and root area were significantly higher by 21, 35, 24, and 26%, respectively, in tomato treated plants with the protein hydrolysate at 6 ml/L than untreated plants. In Experiment 3, the application of the protein hydrolysate at all doses (0.375, 0.75, 1.5, and 3.0 ml/L) significantly increased the shoot length of the gibberellin-deficient dwarf pea plants by an average value of 33% in comparison with the control treatment. Increasing the concentration of the protein hydrolysate from 0 to 10 ml/L increased the total dry biomass, SPAD index, and leaf nitrogen content by 20.5, 15, and 21.5%, respectively. Thus the application of plant-derived protein hydrolysate containing amino acids and small peptides elicited a hormone-like activity, enhanced nitrogen uptake and consequently crop performances. PMID:25250039

Colla, Giuseppe; Rouphael, Youssef; Canaguier, Renaud; Svecova, Eva; Cardarelli, Mariateresa

2014-01-01

256

Biostimulant action of a plant-derived protein hydrolysate produced through enzymatic hydrolysis  

PubMed Central

The aim of this study was to evaluate the biostimulant action (hormone like activity, nitrogen uptake, and growth stimulation) of a plant-derived protein hydrolysate by means of two laboratory bioassays: a corn (Zea mays L.) coleoptile elongation rate test (Experiment 1), a rooting test on tomato cuttings (Experiment 2); and two greenhouse experiments: a dwarf pea (Pisum sativum L.) growth test (Experiment 3), and a tomato (Solanum lycopersicum L.) nitrogen uptake trial (Experiment 4). Protein hydrolysate treatments of corn caused an increase in coleoptile elongation rate when compared to the control, in a dose-dependent fashion, with no significant differences between the concentrations 0.75, 1.5, and 3.0 ml/L, and inodole-3-acetic acid treatment. The auxin-like effect of the protein hydrolysate on corn has been also observed in the rooting experiment of tomato cuttings. The shoot, root dry weight, root length, and root area were significantly higher by 21, 35, 24, and 26%, respectively, in tomato treated plants with the protein hydrolysate at 6 ml/L than untreated plants. In Experiment 3, the application of the protein hydrolysate at all doses (0.375, 0.75, 1.5, and 3.0 ml/L) significantly increased the shoot length of the gibberellin-deficient dwarf pea plants by an average value of 33% in comparison with the control treatment. Increasing the concentration of the protein hydrolysate from 0 to 10 ml/L increased the total dry biomass, SPAD index, and leaf nitrogen content by 20.5, 15, and 21.5%, respectively. Thus the application of plant-derived protein hydrolysate containing amino acids and small peptides elicited a hormone-like activity, enhanced nitrogen uptake and consequently crop performances. PMID:25250039

Colla, Giuseppe; Rouphael, Youssef; Canaguier, Renaud; Svecova, Eva; Cardarelli, Mariateresa

2014-01-01

257

Sterol carrier protein-x gene and effects of sterol carrier protein-2 inhibitors on lipid uptake in Manduca sexta  

PubMed Central

Background Cholesterol uptake and transportation during the feeding larval stages are critical processes in insects because they are auxotrophic for exogenous (dietary) cholesterol. The midgut is the main site for cholesterol uptake in many insects. However, the molecular mechanism by which dietary cholesterol is digested and absorbed within the midgut and then released into the hemolymph for transportation to utilization or storage sites is poorly understood. Sterol carrier proteins (SCP), non-specific lipid transfer proteins, have been speculated to be involved in intracellular cholesterol transfer and metabolism in vertebrates. Based on the high degree of homology in the conserved sterol transfer domain to rat and human SCP-2, it is supposed that insect SCP-2 has a parallel function to vertebrate SCP-2. Results We identified the Manduca sexta sterol carrier protein-x and the sterol carrier protein-2 (MsSCP-x/SCP-2) gene from the larval fat body and the midgut cDNAs. The MsSCP-x/SCP-2 protein has a high degree of homology in the SCP-2 domain to other insects' SCP-2. Transcripts of MsSCP-2 were detected at high levels in the midgut and the fat body of M. sexta during the larval stages. Recombinant MsSCP-2 bound to NBD-cholesterol with high affinity, which was suppressed by sterol carrier protein-2 inhibitors. Conclusions The results suggest that MsSCP-2 may function as a lipid carrier protein in vivo, and targeting insect SCP-2 may be a viable approach for the development of new insecticides. PMID:20534138

2010-01-01

258

2-Amino-nonyl-6-methoxyl-tetralin muriate inhibits sterol C-14 reductase in the ergosterol biosynthetic pathway  

PubMed Central

Aim: To investigate the action mechanism of a novel chemical structural aminotetralin derivate, 2-Amino-Nonyl-6-Methoxyl-Tetralin Muriate (10b), against Candida albicans (C albicans) in the ergosterol biosynthetic pathway. Methods: Antifungal susceptibility test of 10b was carried out using broth microdilution method, the action mechanism of 10b against C albicans was investigated by GC-MS spectrometry and real-time RT-PCR assay, and cytotoxicity of 10b in vitro was assessed by MTS/PMS reduction assay. Results: 10b reduced the ergosterol content markedly, and the 50% ergosterol content inhibitory concentration (ECIC50 value) was 0.08 ?g/mL. Although the sterol composition of 10b-grown cells was completely identical with that of erg24 strain, the content of ergosta-8,14,22-trienol in 10b-grown cells was much higher than that in erg24 strain. Real-time RT-PCR assay revealed a global upregulation of sterol metabolism genes. In addition, the 50% inhibitory concentration (IC50 value) of 10b was 11.30 ?g/mL for murine embryonic fibroblasts and 35.70 ?g/mL for human normal liver cells. Conclusion: 10b possessed a mode of action different from that of azoles and morpholines, whose targets were sterol C-14 reductase (encoded by ERG24 gene) and sterol C-5 desaturase (encoded by ERG3) related enzyme. Although 10b seemed to reduce MTS/PMS reduction in a dose dependent manner, IC50 value for mammalian cells was much higher than 50% minimum inhibitory concentration (MIC50) value for C albicans. This indicates that the formulation is preliminarily safe and warrants further study for possible human applications. PMID:19915585

Liang, Rong-mei; Cao, Yong-bing; Fan, Kai-hua; Xu, Yi; Gao, Ping-hui; Zhou, You-jun; Dai, Bao-di; Tan, Yong-hong; Wang, Shi-hua; Tang, Hui; Liu, Hong-tao; Jiang, Yuan-ying

2009-01-01

259

Plant-derived leading compounds for chemotherapy of human immunodeficiency virus (HIV) infection.  

PubMed

Many compounds of plant origin have been identified that inhibit different stages in the replication cycle of human immunodeficiency virus (HIV): 1) virus adsorption: chromone alkaloids (schumannificine), isoquinoline alkaloids (michellamines), sulphated polysaccharides and polyphenolics, flavonoids, coumarins (glycocoumarin, licopyranocoumarin) phenolics (caffeic acid derivatives, galloyl acid derivatives, catechinic acid derivatives), tannins and triterpenes (glycyrrhizin and analogues, soyasaponin and analogues); 2) virus-cell fusion: lectins (mannose- and N-acetylglucosamine-specific) and triterpenes (betulinic acid and analogues); 3) reverse transcription; alkaloids (benzophenanthridines, protoberberines, isoquinolines, quinolines), coumarins (calanolides and analogues), flavonoids, phloroglucinols, lactones (protolichesterinic acid), tannins, iridoids (fulvoplumierin) and triterpenes; 4) integration: coumarins (3-substituted-4-hydroxycoumarins), depsidones, O-caffeoyl derivatives, lignans (arctigenin and analogues) and phenolics (curcumin); 5) translation: single chain ribosome inactivating proteins (SCRIP's); 6) proteolytic cleavage (protease inhibition): saponins (ursolic and maslinic acids), xanthones (mangostin and analogues) and coumarins; 7) glycosylation: alkaloids including indolizidines (castanospermine and analogues), piperidines (1-deoxynojirimicin and analogues) and pyrrolizidines (australine and analogues); 8) assembly/release: naphthodianthrones (hypericin and pseudohypericin), photosensitisers (terthiophenes and furoisocoumarins) and phospholipids. The target of action of several anti-HIV substances including alkaloids (O-demethyl-buchenavianine, papaverine), polysaccharides (acemannan), lignans (intheriotherins, schisantherin), phenolics (gossypol, lignins, catechol dimers such as peltatols, naphthoquinones such as conocurvone) and saponins (celasdin B, Gleditsia and Gymnocladus saponins), has not been elucidated or does not fit in the proposed scheme. Only a very few of these plant-derived anti-HIV products have been used in a limited number of patients suffering from AIDS viz. glycyrrhizin, papaverine, trichosanthin, castanospermine, N-butyl-1-deoxynojirimicin and acemannan. PMID:9525100

Vlietinck, A J; De Bruyne, T; Apers, S; Pieters, L A

1998-03-01

260

Differential effects of fenpropimorph and fenhexamid, two sterol biosynthesis inhibitor fungicides, on arbuscular mycorrhizal development and sterol metabolism in carrot roots.  

PubMed

Sterols composition of transformed carrot roots incubated in presence of increasing concentrations of fenpropimorph (0.02; 0.2; 2mgl(-1)) and fenhexamid (0.02; 0.2; 2; 20mgl(-1)), colonized or not by Glomus intraradices was determined. In mycorrhizal roots treated with fenpropimorph, normal Delta(5)-sterols were replaced by unusual compounds such as 9beta,19-cyclopropylsterols (24-methylpollinastanol), Delta(8,14)-sterols (ergosta-8,14-dienol, stigmasta-8,14-dienol), Delta(8)-sterols (Delta(8) sitosterol) and Delta(7)-sterols (ergosta-7,22-dienol). After application of fenpropimorph, a drastic reduction of the mycorrhizal root growth, root colonization and extraradical fungal development was observed. Application of fenhexamid did not modify sterol profiles and the total colonization of roots. But the arbuscule frequency of the fungal partner was significantly affected. Comparison of the effects caused by the tested fungicides indicates that the usual phytosterols may be involved in symbiosis development. Indeed, observed modifications of root sterols composition could explain the high fenpropimorph toxicity to the AM symbiosis. However, the absence of sterolic modifications in the roots treated with fenhexamid could account for its more limited impact on mycorrhization. PMID:19007946

Campagnac, Estelle; Fontaine, Joël; Sahraoui, Anissa Lounčs-Hadj; Laruelle, Frédéric; Durand, Roger; Grandmougin-Ferjani, Anne

2008-12-01

261

Intracellular Reprogramming of Expression, Glycosylation, and Function of a Plant-Derived Antiviral Therapeutic Monoclonal Antibody  

PubMed Central

Plant genetic engineering, which has led to the production of plant-derived monoclonal antibodies (mAbPs), provides a safe and economically effective alternative to conventional antibody expression methods. In this study, the expression levels and biological properties of the anti-rabies virus mAbP SO57 with or without an endoplasmic reticulum (ER)-retention peptide signal (Lys-Asp-Glu-Leu; KDEL) in transgenic tobacco plants (Nicotiana tabacum) were analyzed. The expression levels of mAbP SO57 with KDEL (mAbPK) were significantly higher than those of mAbP SO57 without KDEL (mAbP) regardless of the transcription level. The Fc domains of both purified mAbP and mAbPK and hybridoma-derived mAb (mAbH) had similar levels of binding activity to the Fc?RI receptor (CD64). The mAbPK had glycan profiles of both oligomannose (OM) type (91.7%) and Golgi type (8.3%), whereas the mAbP had mainly Golgi type glycans (96.8%) similar to those seen with mAbH. Confocal analysis showed that the mAbPK was co-localized to ER-tracker signal and cellular areas surrounding the nucleus indicating accumulation of the mAbP with KDEL in the ER. Both mAbP and mAbPK disappeared with similar trends to mAbH in BALB/c mice. In addition, mAbPK was as effective as mAbH at neutralizing the activity of the rabies virus CVS-11. These results suggest that the ER localization of the recombinant mAbP by KDEL reprograms OM glycosylation and enhances the production of the functional antivirus therapeutic antibody in the plant. PMID:23967055

Lee, Kyung-Jin; Kim, Young-Kwan; So, Yang-Kang; Ryu, Jae-Sung; Oh, Seung-Han; Han, Yeon-Soo; Ko, Kinarm; Choo, Young-Kug; Park, Sung-Joo; Brodzik, Robert; Lee, Kyoung-Ki; Oh, Doo-Byoung; Hwang, Kyung-A; Koprowski, Hilary; Lee, Yong Seong; Ko, Kisung

2013-01-01

262

50 CFR 23.92 - Are any wildlife or plants, and their parts, products, or derivatives, exempt?  

Code of Federal Regulations, 2011 CFR

...products, or derivatives that are not designated. (2) Plant hybrids . (i) Seeds and pollen (including pollinia), cut flowers, and flasked seedlings or tissue cultures of hybrids that qualify as artificially propagated (see § 23.64) and that...

2011-10-01

263

A potential plant-derived antifungal acetylenic acid mediates its activity by interfering with fatty acid homeostasis  

Technology Transfer Automated Retrieval System (TEKTRAN)

6-Nonadecynoic acid (6-NDA), a plant-derived acetylenic acid, exhibits strong inhibitory activity against the human fungal pathogens Candida albicans, Aspergillus fumigatus, and Trichophyton mentagrophytes. In the present study, transcriptional profiling coupled with mutant and biochemical analyses...

264

Structural complex of sterol 14[alpha]-demethylase (CYP51) with 14[alpha]-methylenecyclopropyl-[delta]7-24, 25-dihydrolanosterol[S  

SciTech Connect

Sterol 14{alpha}-demethylase (CYP51) that catalyzes the removal of the 14{alpha}-methyl group from the sterol nucleus is an essential enzyme in sterol biosynthesis, a primary target for clinical and agricultural antifungal azoles and an emerging target for antitrypanosomal chemotherapy. Here, we present the crystal structure of Trypanosoma (T) brucei CYP51 in complex with the substrate analog 14{alpha}-methylenecyclopropyl-{Delta}7-24,25-dihydrolanosterol (MCP). This sterol binds tightly to all protozoan CYP51s and acts as a competitive inhibitor of F105-containing (plant-like) T. brucei and Leishmania (L) infantum orthologs, but it has a much stronger, mechanism-based inhibitory effect on I105-containing (animal/fungi-like) T. cruzi CYP51. Depicting substrate orientation in the conserved CYP51 binding cavity, the complex specifies the roles of the contact amino acid residues and sheds new light on CYP51 substrate specificity. It also provides an explanation for the effect of MCP on T. cruzi CYP51. Comparison with the ligand-free and azole-bound structures supports the notion of structural rigidity as the characteristic feature of the CYP51 substrate binding cavity, confirming the enzyme as an excellent candidate for structure-directed design of new drugs, including mechanism-based substrate analog inhibitors.

Hargrove, Tatiana Y.; Wawrzak, Zdzislaw; Liu, Jialin; Waterman, Michael R.; Nes, W. David; Lepesheva, Galina I. (Vanderbilt); (TTU); (NWU)

2012-06-28

265

Co-opted Oxysterol-Binding ORP and VAP Proteins Channel Sterols to RNA Virus Replication Sites via Membrane Contact Sites  

PubMed Central

Viruses recruit cellular membranes and subvert cellular proteins involved in lipid biosynthesis to build viral replicase complexes and replication organelles. Among the lipids, sterols are important components of membranes, affecting the shape and curvature of membranes. In this paper, the tombusvirus replication protein is shown to co-opt cellular Oxysterol-binding protein related proteins (ORPs), whose deletion in yeast model host leads to decreased tombusvirus replication. In addition, tombusviruses also subvert Scs2p VAP protein to facilitate the formation of membrane contact sites (MCSs), where membranes are juxtaposed, likely channeling lipids to the replication sites. In all, these events result in redistribution and enrichment of sterols at the sites of viral replication in yeast and plant cells. Using in vitro viral replication assay with artificial vesicles, we show stimulation of tombusvirus replication by sterols. Thus, co-opting cellular ORP and VAP proteins to form MCSs serves the virus need to generate abundant sterol-rich membrane surfaces for tombusvirus replication. PMID:25329172

Barajas, Daniel; Xu, Kai; de Castro Martín, Isabel Fernández; Sasvari, Zsuzsanna; Brandizzi, Federica; Risco, Cristina; Nagy, Peter D.

2014-01-01

266

Pneumocysterol [(24Z)-ethylidenelanost-8-en-3?-ol], a rare sterol detected in the opportunistic pathogen Pneumocystis carinii hominis: Structural identity and chemical synthesis  

PubMed Central

Pneumocystis carinii pneumonia (PcP) remains among the most prevalent opportunistic infections among AIDS patients. Currently, drugs used clinically for deep mycosis act by binding ergosterol or disrupting its biosynthesis. Although classified as a fungus, P. carinii lacks ergosterol. Instead, the pathogen synthesizes a number of distinct ?7, 24-alkylsterols, despite the abundance of cholesterol, which it can scavenge from the lung alveolus. Thus, the pathogen-specific sterols appear vital for organism survival and proliferation. In the present study, high concentrations of a C32 sterol were found in human-derived P. carinii hominis. The definitive structural identities of two C-24 alkylated lanosterol compounds, previously not reported for rat-derived P. carinii carinii, were determined by using GLC, MS, and NMR spectroscopy together with the chemical syntheses of authentic standards. The C31 and C32 sterols were identified as euphorbol (24-methylenelanost-8-en-3?-ol) and pneumocysterol [(24Z)-ethylidenelanost-8-en-3?-ol], respectively. The identification of these and other 24-alkylsterols in P. carinii hominis suggests that (i) sterol C-24 methyltransferase activities are extraordinarily high in this organism, (ii) 24-alkylsterols are important components of the pathogen’s membranes, because the addition of these side groups onto the sterol side chain requires substantial ATP equivalents, and (iii) the inefficacy of azole drugs against P. carinii can be explained by the ability of this organism to form 24-alkysterols before demethylation of the lanosterol nucleus. Because mammals cannot form 24-alkylsterols, their biosyntheses in P. carinii are attractive targets for the development of chemotherapeutic strategies against this opportunistic infection. PMID:9874778

Kaneshiro, Edna S.; Amit, Zunika; Swonger, Mardie M.; Kreishman, George P.; Brooks, Elwood E.; Kreishman, Mara; Jayasimhulu, Koka; Parish, Edward J.; Sun, Hang; Kizito, Stephen A.; Beach, David H.

1999-01-01

267

Derivatives  

NSDL National Science Digital Library

Murray Bourne developed the Interactive Mathematics site while working as a mathematics lecturer at Ngee Ann Polytechnic in Singapore. The site contains numerous mathematics tutorials and resources for students and teachers alike. This specific page is focused on differentiation, or finding derivatives. Bourne walks users through an introduction to differentiation and limits, and then moves on to more specific applications like rate of change, derivatives of polynomials, and differentiating powers of a function. Each topic includes graphs and interactive materials designed to aid users in understanding the presented concepts. The information here is presented in a clear, straightforward manner that is appropriate for introductory and advanced calculus students alike.

Bourne, Murray

268

Plant regeneration from immature inflorescence derived callus cultures of salt tolerant kallar grass (Leptochloa fusca L.).  

PubMed

Efficient plant regeneration has been achieved from immature inflorescence derived callus cultures of salt tolerant grass Leptochloa fusca (L.). Young inflorescence explants displayed wide-ranging responses for callus induction and plant regeneration when subjected to different cold treatment durations and without cold treatment exposure (control) prior to its inoculation to MS medium supplemented with different concentrations/combinations of plant growth regulators (PGRs). The PGRs included auxins: 2, 4-dichlorophenoxy acetic acid (2, 4-D), picloram (Pic), 3, 6-dichloro-2-methoxy benzoic acid (dicamba) and cytokinins: Kinetin (KN), N6-benzyl adenine (BA). These treatments promoted different callus induction frequencies as well as various callus types such as type 1, type 2 and type 3. Induction of type 2 callus (white and compact) with potential for regeneration was obtained from cold treated (3 days at 10 °C) immature inflorescence cultured on MS medium containing 2.0 mg/l dicamba and 0.25 mg/l BA. The study demonstrated that 2.0 mg/l dicamba and 0.25 mg/l BA induced callus promoted improved frequency compared to zilch shoot regeneration response with other combinations involving 2, 4-D, picloram, KN and BA. Full strength MS supplemented with 2.0 mg/l NAA and 0.5 mg/l BA was found to be optimal for plant regeneration. The regeneration frequencies ranged from 13.8?±?1.366 to 55.5?±?2.766 with highest number of shoots (19.1?±?0.560) per 50-60 mg of callus as explants after 28 days of inoculation. Plant regeneration was also obtained on the dicamba callus induction medium itself within 21 days inoculation of immature inflorescence explants. Half strength MS medium both semisolid and liquid devoid of plant growth regulators promoted highest frequency (92.8?±?4.099 and 100?±?0.00) of rooting in regenerated shoots. Plants with well developed roots were successfully transferred to pots and grown to maturity with normal flowering and seed set. This is the first report on induction of callus and subsequent plant regeneration in kallar grass using immature inflorescence explants. PMID:24082497

Praveena, M; Giri, C C

2012-10-01

269

Determination of tocopherols and sterols by capillary gas chromatography  

Microsoft Academic Search

A method is described for simultaneously determining tocopherols and sterols in fats and oils by quantitative capillary gas\\u000a chromatography. Samples containing ca. 100 mg of lipid were saponified in capped tubes with aqueous KOH by heating for 8 min\\u000a at 80 C; the unsaponifiable fraction was extracted with cyclohexane, freed of solvent, derivatized to form the trimethylsilyl\\u000a ethers of both

H. T. Slover; R. H. THOMPSON JR.; G. V. Merola

1983-01-01

270

Expression of a fungal sterol desaturase improves tomato drought tolerance, pathogen resistance and nutritional quality.  

PubMed

Crop genetic engineering mostly aims at improving environmental stress (biotic and abiotic) tolerance as well as nutritional quality. Empowering a single crop with multiple traits is highly demanding and requires manipulation of more than one gene. However, we report improved drought tolerance and fungal resistance along with the increased iron and polyunsaturated fatty acid content in tomato by expressing a single gene encoding C-5 sterol desaturase (FvC5SD) from an edible fungus Flammulina velutipes. FvC5SD is an iron binding protein involved in ergosterol biosynthesis. Morphological and biochemical analyses indicated ?23% more epicuticular wax deposition in leaves of transgenic plants that provides an effective waterproof barrier resulting in improved protection from drought and infection by phytopathogenic fungus Sclerotiniasclerotiorum. Furthermore, the transgenic fruits have improved nutritional value attributed to enhanced level of beneficial PUFA and 2-3 fold increase in total iron content. This strategy can be extended to other economically important crops. PMID:23230516

Kamthan, Ayushi; Kamthan, Mohan; Azam, Mohammad; Chakraborty, Niranjan; Chakraborty, Subhra; Datta, Asis

2012-01-01

271

Derivate  

NSDL National Science Digital Library

In this activity, students input functions in order to calculate the derivative and tangent line of that function. This activity allows students to explore tangent lines of various functions. This activity includes supplemental materials, including background information about the topics covered, a description of how to use the application, and exploration questions for use with the java applet.

2010-01-01

272

Biochemical and molecular analysis of plants derived from embryogenic tissue cultures of napier grass ( Pennisetum purpureum K. Schum)  

Microsoft Academic Search

We have investigated the extent of biochemical and molecular variation in 63 plants of napier grass (Pennisetum purpureum K. Schum.) regenerated from 3- to 24-week-old embryogenic callus cultures. The calli were derived from cultured basal segments of young leaves and immature inflorescences obtained from a single fieldgrown donor plant. The entire population was analyzed for the activity of 14 isozyme

V. B. Shenoy; I. K. Vasil

1992-01-01

273

First Report of Plant Regeneration via Somatic Embryogenesis from Shoot Apex-derived Callus of Hedychium muluense  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plants were successfully regenerated via somatic embryogenesis from shoot apex-derived callus of Hedychium muluense R.M. Smith, an important monocotyledonous ornamental ginger plant. Callus was induced on a modified Murashige and Skoog (MS) medium supplemented with 9.05 µM 2-4, D and 4.6µM kinetin. ...

274

Bioprocessing of plant-derived virus-like particles of Norwalk virus capsid protein under current Good Manufacture Practice regulations  

PubMed Central

Despite the success in expressing a variety of subunit vaccine proteins in plants and the recent stride in improving vaccine accumulation levels by transient expression systems, there is still no plant-derived vaccine that has been licensed for human use. The lack of commercial success of plant-made vaccines lies in several technical and regulatory barriers that remain to be overcome. These challenges include the lack of scalable downstream processing procedures, the uncertainty of regulatory compliance of production processes, and the lack of demonstration of plant-derived products that meet the required standards of regulatory agencies in identity, purity, potency and safety. In this study, we addressed these remaining challenges and successfully demonstrate the ability of using plants to produce a pharmaceutical grade Norwalk virus (NV) vaccine under current Good Manufacture Practice (cGMP) guidelines at multiple gram scales. Our results demonstrate that an efficient and scalable extraction and purification scheme can established for processing virus-like particles (VLP) of NV capsid protein (NVCP). We successfully operated the upstream and downstream NVCP production processes under cGMP regulations. Furthermore, plant-derived NVCP VLP demonstrates the identity, purity, potency and safety that meet the preset release specifications. This material is being tested in a Phase I human clinical trial. This research provides the first report of producing a plant-derived vaccine at scale under cGMP regulations in an academic setting and an important step for plant-produced vaccines to become a commercial reality. PMID:22134876

Lai, Huafang; Chen, Qiang

2012-01-01

275

Attenuation of Leishmania infantum chagasi Metacyclic Promastigotes by Sterol Depletion  

PubMed Central

The infectious metacyclic promastigotes of Leishmania protozoa establish infection in a mammalian host after they are deposited into the dermis by a sand fly vector. Several Leishmania virulence factors promote infection, including the glycosylphosphatidylinositol membrane-anchored major surface protease (MSP). Metacyclic Leishmania infantum chagasi promastigotes were treated with methyl-beta-cyclodextrin (M?CD), a sterol-chelating reagent, causing a 3-fold reduction in total cellular sterols as well as enhancing MSP release without affecting parasite viability in vitro. M?CD-treated promastigotes were more susceptible to complement-mediated lysis than untreated controls and reduced the parasite load 3-fold when inoculated into BALB/c mice. Paradoxically, M?CD-treated promastigotes caused a higher initial in vitro infection rate in human or murine macrophages than untreated controls, although their intracellular multiplication was hindered upon infection establishment. There was a corresponding larger amount of covalently bound C3b than iC3b on the parasite surfaces of M?CD-treated promastigotes exposed to healthy human serum in vitro, as well as loss of MSP, a protease that enhances C3b cleavage to iC3b. Mass spectrometry showed that M?CD promotes the release of proteins into the extracellular medium, including both MSP and MSP-like protein (MLP), from virulent metacyclic promastigotes. These data support the hypothesis that plasma membrane sterols are important for the virulence of Leishmania protozoa at least in part through retention of membrane virulence proteins. PMID:23630964

Gaur Dixit, Upasna; Barker, Jason H.; Teesch, Lynn M.; Love-Homan, Laurie; Donelson, John E.; Wilson, Mary E.

2013-01-01

276

Conversion of exogenous cholesterol into glycoalkaloids in potato shoots, using two methods for sterol solubilisation.  

PubMed

Steroidal glycoalkaloids (SGA) are toxic secondary metabolites naturally occurring in the potato, as well as in certain other Solanaceous plant species, such as tomato, eggplant and pepper. To investigate the steroidal origin of SGA biosynthesis, cut potato shoots were fed cholesterol labelled with deuterium (D) in the sterol ring structure (D5- or D6-labelled), or side chain (D7-labelled), and analysed after three or five weeks. The labelled cholesterol and presence of D-labelled SGA were analysed by GC-MS and LC-MS/MS, respectively. When feeding D-labelled cholesterol solubilised in Tween-80, labelled cholesterol in free form became present in both leaves and stems, although the major part was recovered as steryl esters. Minor amounts of D-labelled SGA (?-solanine and ?-chaconine) were identified in cholesterol-treated shoots, but not in blank controls, or in shoots fed D6-27-hydroxycholesterol. Solubilising the labelled cholesterol in methyl-?-cyclodextrin instead of Tween-80 increased the levels of labelled SGA up to 100-fold, and about 1 mole% of the labelled cholesterol was recovered as labelled SGA in potato leaves. Both side chain and ring structure D labels were retained in SGA, showing that the entire cholesterol molecule is converted to SGA. However, feeding side chain D7-labelled cholesterol resulted in D5-labelled SGA, indicating that two hydrogen atoms were released during formation of the SGA nitrogen-containing ring system. Feeding with D7-sitosterol did not produce any labelled SGA, indicating that cholesterol is a specific SGA precursor. In conclusion, we have demonstrated a superior performance of methyl-?-cyclodextrin for delivery of cholesterol in plant tissue feeding experiments, and given firm evidence for cholesterol as a specific sterol precursor of SGA in potato. PMID:24349406

Petersson, Erik V; Nahar, Nurun; Dahlin, Paul; Broberg, Anders; Tröger, Rikard; Dutta, Paresh C; Jonsson, Lisbeth; Sitbon, Folke

2013-01-01

277

Conversion of Exogenous Cholesterol into Glycoalkaloids in Potato Shoots, Using Two Methods for Sterol Solubilisation  

PubMed Central

Steroidal glycoalkaloids (SGA) are toxic secondary metabolites naturally occurring in the potato, as well as in certain other Solanaceous plant species, such as tomato, eggplant and pepper. To investigate the steroidal origin of SGA biosynthesis, cut potato shoots were fed cholesterol labelled with deuterium (D) in the sterol ring structure (D5- or D6-labelled), or side chain (D7-labelled), and analysed after three or five weeks. The labelled cholesterol and presence of D-labelled SGA were analysed by GC-MS and LC-MS/MS, respectively. When feeding D-labelled cholesterol solubilised in Tween-80, labelled cholesterol in free form became present in both leaves and stems, although the major part was recovered as steryl esters. Minor amounts of D-labelled SGA (?-solanine and ?-chaconine) were identified in cholesterol-treated shoots, but not in blank controls, or in shoots fed D6-27-hydroxycholesterol. Solubilising the labelled cholesterol in methyl-?-cyclodextrin instead of Tween-80 increased the levels of labelled SGA up to 100-fold, and about 1 mole% of the labelled cholesterol was recovered as labelled SGA in potato leaves. Both side chain and ring structure D labels were retained in SGA, showing that the entire cholesterol molecule is converted to SGA. However, feeding side chain D7-labelled cholesterol resulted in D5-labelled SGA, indicating that two hydrogen atoms were released during formation of the SGA nitrogen-containing ring system. Feeding with D7-sitosterol did not produce any labelled SGA, indicating that cholesterol is a specific SGA precursor. In conclusion, we have demonstrated a superior performance of methyl-?-cyclodextrin for delivery of cholesterol in plant tissue feeding experiments, and given firm evidence for cholesterol as a specific sterol precursor of SGA in potato. PMID:24349406

Petersson, Erik V.; Nahar, Nurun; Dahlin, Paul; Broberg, Anders; Tröger, Rikard; Dutta, Paresh C.; Jonsson, Lisbeth; Sitbon, Folke

2013-01-01

278

Practical synthesis of natural plant-growth regulator 2-azahypoxanthine, its derivatives, and biotin-labeled probes.  

PubMed

We describe a practical, large-scale synthesis of the "fairy-ring" plant-growth regulator 2-azahypoxanthine (AHX), and its biologically active hydroxyl metabolite (AOH) and riboside derivative (AHXr). AHXr, a biosynthetic intermediate, was synthesized from inosine via a biomimetic route. Biotinylated derivatives of AHX and AHXr were also synthesized as probes for mechanistic studies. PMID:24802664

Ikeuchi, Kazutada; Fujii, Ryosuke; Sugiyama, Shimpei; Asakawa, Tomohiro; Inai, Makoto; Hamashima, Yoshitaka; Choi, Jae-Hoon; Suzuki, Tomohiro; Kawagishi, Hirokazu; Kan, Toshiyuki

2014-06-21

279

Origins of the mycoplasmas: sterol-nonrequiring mycoplasmas evolved from streptococci.  

PubMed Central

We report the establishment of a phylogenetic relationship between the sterol-nonrequiring mycoplasmas (Acholeplasma species) and streptococci. Three specific antisera prepared against purified Streptococcus faecalis fructose diphosphate aldolase and glyceraldehyde-3-phosphate dehydrogenase and Pediococcus cerevisiae glyceraldehyde-3-phosphate dehydrogenase were used for comparative enzyme immunological studies; the Ouchterlony double-diffusion technique and the quantitative microcomplement fixation procedure were employed. The reactions obtained provide evidence showing that all seven ACholeplasma species studied (A. laidlawii, A. granularum, A. modicum, A. oculi, A. axanthum. A. hippikon, and A. equifetale) are phylogenetically related to streptococci and that they evolved from streptococci. The data strongly suggest that the acholeplasmas comprise a distinct evolutionary group that has diverged from streptococci belonging to Lancefield group D or N. No reactions were observed between these enzyme antisera and cell extracts from six fermentative Mycoplasma species. These results support the view that mycoplasmas are derived from various bacteria. Images PMID:6176574

Neimark, H; London, J

1982-01-01

280

Characterization of sterols by gas chromatography-mass spectrometry of the trimethylsilyl ethers  

Microsoft Academic Search

The utility of combined gas chromatography-mass spectrometry in the analysis and characterization of sterols has been explored.\\u000a Methylene unit (MU) values and principal mass spectrometric data are presented for trimethylsilyl ethers of 28 sterols, including\\u000a the major natural sterols. The diagnostic value of the fragmentation of trimethylsilyl ethers of ?5-3 ?-hydroxysteroids has been confirmed. Characteristic fragmentations of ?4-3 ?-trimethylsilyloxysteroids, and

C. J. W. Brooks; E. C. Horning; J. S. Young

1968-01-01

281

Sterol Biosynthesis Inhibitors: Potential for Transition State Analogs and Mechanism-Based Inactivators Targeted at Sterol Methyltransferase  

Microsoft Academic Search

Sterol biosynthesis inhibitors (SBIs), discovered in the late 1960s and subsequently used commercially to treat ergosterol-dependent\\u000a fungal diseases, represent a unique drug class targeted at an enzyme in a biosynthetic pathway. To date, few drugs have been\\u000a commercialized as enzyme inhibitors; yet, prescription of SBIs has emerged as the gold standard for some cases of non-life-threatening\\u000a antifungal chemotherapy and in

Zhihong Song; W. David Nes

2007-01-01

282

Large-scale Gene Ontology analysis of plant transcriptome-derived sequences retrieved by AFLP technology  

PubMed Central

Background After 10-year-use of AFLP (Amplified Fragment Length Polymorphism) technology for DNA fingerprinting and mRNA profiling, large repertories of genome- and transcriptome-derived sequences are available in public databases for model, crop and tree species. AFLP marker systems have been and are being extensively exploited for genome scanning and gene mapping, as well as cDNA-AFLP for transcriptome profiling and differentially expressed gene cloning. The evaluation, annotation and classification of genomic markers and expressed transcripts would be of great utility for both functional genomics and systems biology research in plants. This may be achieved by means of the Gene Ontology (GO), consisting in three structured vocabularies (i.e. ontologies) describing genes, transcripts and proteins of any organism in terms of their associated cellular component, biological process and molecular function in a species-independent manner. In this paper, the functional annotation of about 8,000 AFLP-derived ESTs retrieved in the NCBI databases was carried out by using GO terminology. Results Descriptive statistics on the type, size and nature of gene sequences obtained by means of AFLP technology were calculated. The gene products associated with mRNA transcripts were then classified according to the three main GO vocabularies. A comparison of the functional content of cDNA-AFLP records was also performed by splitting the sequence dataset into monocots and dicots and by comparing them to all annotated ESTs of Arabidopsis and rice, respectively. On the whole, the statistical parameters adopted for the in silico AFLP-derived transcriptome-anchored sequence analysis proved to be critical for obtaining reliable GO results. Such an exhaustive annotation may offer a suitable platform for functional genomics, particularly useful in non-model species. Conclusion Reliable GO annotations of AFLP-derived sequences can be gathered through the optimization of the experimental steps and the statistical parameters adopted. The Blast2GO software was shown to represent a comprehensive bioinformatics solution for an annotation-based functional analysis. According to the whole set of GO annotations, the AFLP technology generates thorough information for angiosperm gene products and shares common features across angiosperm species and families. The utility of this technology for structural and functional genomics in plants can be implemented by serial annotation analyses of genome-anchored fragments and organ/tissue-specific repertories of transcriptome-derived fragments. PMID:18652646

Botton, Alessandro; Galla, Giulio; Conesa, Ana; Bachem, Christian; Ramina, Angelo; Barcaccia, Gianni

2008-01-01

283

Characterization of sterols in refined borage oil by GC-MS  

Microsoft Academic Search

Borage oil sterols were isolated by TLC and characterized using GC and GC-MS. Several diunsaturated ?5-sterols, some of them not previously recorded in vegetable oils, were found. Of these, 24-methylcholesta-5,23-dienol and\\u000a 24-ethylcholesta-5,23-dienol could be useful markers for borage oil. Two other diunsaturated ?5-sterols that are rarely found in vegetable oils, 24-methylcholesta-5,24(25)-dienol and 24-ethylcholesta-5,24(25)-dienol,\\u000a were identified. The diunsaturated C-24(28)-sterol, isofucosterol, was

Inger Wretensjö; Bo Karlberg

2002-01-01

284

[Micromycetes metabolites--inhibitors of growth and sterol biosynthesis in yeasts].  

PubMed

Antifungal activity of micelial fungus metabolites (of genera Aspergillus, Penicillium, Fusarium, Stachybotris, Cladosporium, Alternaria, Gliocladium, Paecilomyces, Trichoderma etc.) was determined. It was shown that antifungal activity of some micromycetes is due to the formation of substances inhibiting sterols biosynthesis in eucaryote cells. Inhibitors of enzymes of sterols biosynthesis were isolated and their activity was investigated. It was shown, that isolated fungus inhibitors of sterols biosynthesis inhibited the growth of test-organism Rhodotorula rubra and decreased ergosterin level in yeast cells. The qualitative content of yeast cell sterols was not changed in the presence of fungus inhibitors. PMID:12077938

Baranova, N A; Kre?er, V G; Landau, N S; Egorov, N S

2002-01-01

285

Qualitative and quantitative analysis of anthraquinone derivatives in rhizomes of tissue culture-raised Rheum emodi Wall. plants.  

PubMed

This paper presents quantification of five anthraquinone derivatives (emodin glycoside, chrysophanol glycoside, emodin, chrysophanol and physcion) in rhizomes of hardened micro-propagated Rheum emodi plants using high-performance liquid chromatography (HPLC). Aseptic shoot cultures were raised using rhizome buds. Shoot multiplication occurred in both agar gelled and liquid Murashige and Skoog (MS) medium supplemented with 10.0 microM 6-benzylaminopurine (BAP) and 5.0 microM indole-3-butyric acid (IBA). Rooted plantlets obtained on plant growth regulator (PGR)-free medium were transferred to soil with 92% survival. HPLC analysis revealed the presence of five anthraquinone derivatives: emodin glycoside, chrysophanol glycoside, emodin, chrysophanol and physcion in rhizomes of tissue culture-raised plants. Only emodin glycoside (1) and chrysophanol glycoside (2) were present in 6-month-old hardened tissue cultured plants. In addition, the other three derivatives (emodin (3), chrysophanol (4) and physcion (5)) were also detected after 9 months. PMID:20144491

Malik, Sonia; Sharma, Nandini; Sharma, Upendra K; Singh, Narendra P; Bhushan, Shashi; Sharma, Madhu; Sinha, Arun K; Ahuja, Paramvir S

2010-06-15

286

Spreads enriched with three different levels of vegetable oil sterols and the degree of cholesterol lowering in normocholesterolaemic and mildly hypercholesterolaemic subjects  

Microsoft Academic Search

Objective: To investigate the dose-response relationship between cholesterol lowering and three different, relatively low intake levels of plant sterols (0.83, 1.61, 3.24 g\\/d) from spreads. To investigate the effects on lipid-soluble (pro)vitamins.Design: A randomized double-blind placebo controlled balanced incomplete Latin square design using five spreads and four periods. The five study spreads included butter, a commercially available spread and three

HFJ Hendriks; JA Weststrate; T van Vliet; GW Meijer

1999-01-01

287

Sterol-mediated regulation of mevalonic acid synthesis. Accumulation of 4-carboxysterols as the predominant sterols synthesized in a Chinese hamster ovary cell cholesterol auxotroph (mutant 215)  

SciTech Connect

Chinese hamster ovary-215 (CHO-215) mutant cells are auxotrophic for cholesterol. Berry and Chang (Berry, D. J., and Chang, T. Y. (1982) Biochemistry 21, 573-580) suggested that the metabolic lesion was at the level of 4-methyl sterol oxidation. However, the observed cellular accumulation of lanosterol was not consistent with a defect at this metabolic site. With the use of a novel Silica Sep Pak sterol separation procedure, we demonstrated that 60-80% of the acetonesoluble lipid radioactivity in (5-3H)mevalonate-labeled CHO-215 cells was incorporated into acidic sterols. 7(8),Cholesten-4 beta-methyl,4 alpha-carboxy,3 beta-ol was the dominant end product. In addition to this acidic sterol, 7(8),24-cholestadien,4 beta-methyl,4 alpha-carboxy,3 beta-ol and 7(8),24-cholestadien,4 alpha-carboxy,3 beta-ol were also isolated. Incubation of cell-free extracts with (3H)7(8)-cholesten-4 beta-methyl, 4 alpha-carboxy,3 beta-ol and pyridine nucleotides confirmed that CHO-215 4-carboxysterol decarboxylase activity was less than 1% of that for wild type cells. Thus, a correspondence between decreased 4-carboxysterol decarboxylase activity and the spectrum of accumulated sterol products by intact CHO-215 cells was demonstrated. No detectable cholesterol was synthesized by CHO-215 cells. 3H-Product accumulation studies demonstrated that 7(8),24-cholestadien, 4 beta-methyl,4 alpha-carboxy,3 beta-ol increased prior to its subsequent saturation at the delta 24 carbon. Furthermore, the steady state ratio for delta 24-saturated acidic sterols/unsaturated acidic sterols was dependent on media cholesterol source and amount. Finally, the accumulated acidic sterol(s) were not regulatory signal molecules for the modulation of 3-hydroxy-3-methyl-glutaryl coenzyme. A reductase activity in response to cholesterol availability.

Plemenitas, A.; Havel, C.M.; Watson, J.A. (Univ. of California, San Francisco (USA))

1990-10-05

288

Sterol-inhibiting fungicide impacts on soil microbial ecology in Atlantic Coastal Plain soils  

NASA Astrophysics Data System (ADS)

Seventy-five percent of the peanuts (Arachus hypogaia) produced in the United States are grown in the Atlantic Coastal Plain region. Portions of this area, including Alabama and Georgia, exhibit a subtropical climate that promotes soil-borne plant fungal diseases. Most fields receive repeated fungicide applications during the growing season to suppress the disease causing organisms, such as Sclerotium rolfsii, Rhizoctonia solani, and Cylindrocladium parasiticum. Information regarding fungicide effects on the soil microbial community, with components principally responsible for transformation and fate of fungicides and other soil-applied pesticides, is limited. The objectives of the study were to assess soil microbial community response to (1) varying rates of the sterol-inhibiting fungicide tebuconazole (0, single application, season max, 2x season max), and (2) field rates of the sterol-inhibitors cyproconazole, prothioconazole, tebuconazole, and flutriafol, and thiol-competitor chlorothalonil. The sterol-inhibitors exhibited different half lives, as listed in the FOOTPRINT database, ranging from <1 day to >1300 d. Chlorothalonil was chosen because it is the most frequently applied fungicide to peanut. Shifts in the fungi, gram positive and gram negative bacteria, were monitored during the experiments using phospholipid fatty acid (PLFA) profiles. Ergosterol levels and pesticide decay rates were also monitored to evaluate the effectiveness of the fungicide and soil residence time, respectively. In the rate study, the highest rate of tebuconazole reduced the fungal biomarker 18:2?6,9c to 2.6 nmol g-1 dry soil at 17 d, as compared to the control (4.1 nmol g-1 dry soil). However, levels of the fungal PLFA biomarker were similar regardless of rate at 0 and 32 d. The gram negative bacterial PLFA mole percent was greater at 17 d for the two highest rates of tebuconazole, but was similar at 0 and 32 d. Gram positive and fungal mole percents were not affected at any time point. Tebuconazole half life was approximately 10 d regardless of rate. A principle components analysis revealed negligible fungicide impact on PLFA. In the field rate study soil samples were collected immediately following fungicide application to peanut. A laboratory dissipation study, accompanied by PLFA and ergosterol analysis is currently being conducted. Results from the rate experiment indicate that tebuconazole's effect was transient due to rapid dissipation and suggest a gram negative bacterial role. Results obtained from both studies will be useful in predicting the environmental fate and impact of fungicides commonly used for production of peanut and other crops on soil microorganisms.

White, P. M.; Potter, T. L.; Strickland, T. C.

2008-12-01

289

Behavioral effects of plant-derived essential oils in the geller type conflict test in mice.  

PubMed

The present study was conducted to further explore plant-derived essential oils that possess an anticonflict effect using the Geller type conflict test in ICR mice. The benzodiazepine anxiolytic diazepam increased the response (lever pressing) rate during the alarm period (i.e., an anticonflict effect), but the 5-HT1A partial agonist buspirone did not. Oils of juniper, cypress, geranium and jasmine did not produce any effect in this test. Frankincense oil decreased the response rate during the safe period at 1600 mg/kg, but did not exhibit any effect on the response rate during the alarm period. In contrast, lavender oil increased the response rate during the alarm period in a dose-dependent manner in the same manner as diazepam. These results indicate that not only rose oil but also lavender oil possess an anticonflict effect in mice. PMID:10928328

Umezu, T

2000-06-01

290

Plant-derived differences in the composition of aphid honeydew and their effects on colonies of aphid-tending ants  

PubMed Central

In plant–ant–hemipteran interactions, ants visit plants to consume the honeydew produced by phloem-feeding hemipterans. If genetically based differences in plant phloem chemistry change the chemical composition of hemipteran honeydew, then the plant's genetic constitution could have indirect effects on ants via the hemipterans. If such effects change ant behavior, they could feed back to affect the plant itself. We compared the chemical composition of honeydews produced by Aphis nerii aphid clones on two milkweed congeners, Asclepias curassavica and Asclepias incarnata, and we measured the responses of experimental Linepithema humile ant colonies to these honeydews. The compositions of secondary metabolites, sugars, and amino acids differed significantly in the honeydews from the two plant species. Ant colonies feeding on honeydew derived from A. incarnata recruited in higher numbers to artificial diet, maintained higher queen and worker dry weight, and sustained marginally more workers than ants feeding on honeydew derived from A. curassavica. Ants feeding on honeydew from A. incarnata were also more exploratory in behavioral assays than ants feeding from A. curassavica. Despite performing better when feeding on the A. incarnata honeydew, ant workers marginally preferred honeydew from A. curassavica to honeydew from A. incarnata when given a choice. Our results demonstrate that plant congeners can exert strong indirect effects on ant colonies by means of plant-species-specific differences in aphid honeydew chemistry. Moreover, these effects changed ant behavior and thus could feed back to affect plant performance in the field. PMID:25505534

Pringle, Elizabeth G; Novo, Alexandria; Ableson, Ian; Barbehenn, Raymond V; Vannette, Rachel L

2014-01-01

291

Toxicology of a potential molluscicide derived from the plant Solanum xanthocarpum: a preliminary study.  

PubMed

A potential molluscicidal extract, obtained from the indigenous Chinese plant Solanum xanthocarpum (Schrad. and Wendl), was tested for toxicity against snails and fish in static, acute-toxicity tests. The extract had a significant effect on mature and young snails of the amphibious Asian freshwater prosobranch Oncomelania hupensis (Gredler) and also on mature specimens of the freshwater pulmonate snails Biomphalaria glabrata (Say) and Lymnaea stagnalis (Linnaeus). The minimum dose that produced 100% mortality of snails exposed for 48h, 4.321mg/litre, is much less than the threshold, of 100mg/litre, set for a potential molluscicide by the World Health Organization. In contrast, the minimum concentration producing 100% mortality in the fish Gobiocypris rarus (Ye and Fu) was 17.28mg/litre. The extract also limited the extent of water-leaving by snails exposed to it, an important feature for the control of amphibious snails. This extract thus represents a promising plant-derived molluscicide which is worthy of further investigation. PMID:12061979

Wei, F-H; Xu, X-J; Liu, J-B; Dai, Y-H; Dussart, G; Trigwell, J

2002-04-01

292

Proteomics analyses of Bacillus subtilis after treatment with plumbagin, a plant-derived naphthoquinone.  

PubMed

Infectious diseases and increasing antibiotic resistance among diverse classes of microbes are global health concerns and a prime focus of omics systems science applications in novel drug discovery. Plumbagin is a plant-derived naphthoquinone, a natural product that exhibits antibacterial activity against gram-positive bacteria. In the present study, we investigated the antimicrobial effects of plumbagin against Bacillus subtilis using two complementary proteomics techniques: two-dimensional electrophoresis (2-DE) and isobaric tag for relative and absolute quantification (iTRAQ). Comparative quantitative proteomics analysis of plumbagin treated and untreated control samples identified differential expression of 230 proteins (1% FDR, 1.5 fold-change and ?2 peptides) in B. subtilis after plumbagin treatment. Pathway analysis involving the differentially expressed proteins suggested that plumbagin effectively increases heme and protein biosynthesis, whereas fatty acid synthesis was significantly reduced. Gene expression and metabolic activity assays further corroborated the proteomics findings. We anticipate that plumbagin blocks the cell division by altering the membrane permeability required for energy generation. This is the first report, to the best of our knowledge, offering new insights, at proteome level, for the putative mode(s) of action of plumbagin and attendant cellular targets in B. subtilis. The findings also suggest new ways forward for the modern omics-guided drug target discovery, building on traditional plant medicine. PMID:25562197

Reddy, Panga Jaipal; Ray, Sandipan; Sathe, Gajanan J; Prasad, T S Keshava; Rapole, Srikanth; Panda, Dulal; Srivastava, Sanjeeva

2015-01-01

293

More good news about polymeric plant- and algae-derived biomaterials in drug delivery systems.  

PubMed

Natural polymers are continuously investigated for use in pharmaceutical and tissue engineering applications due to the renewability of their supply. Besides the conventional use of natural materials in dosage form design such as fillers, they are progressively investigated as functional excipients in specialised dosage forms. The hydrophilic nature of natural polymers together with their non-toxic and biodegradable properties make them useful in the design of modified release dosage forms. Matrix type tablets and beads made from natural gums and mucilages often exhibit sustained drug release through erosion in combination with swelling. Natural polymers are used to reach different pharmaceutical objectives, for instance, inulin and pectin are plant derived polymers that have suitable properties to produce colon-specific drug delivery. Alginate is an example of a natural polymer that has been used in the formulation of gastro-retentive dosage forms. Different cellulose derived polymers have been investigated as coating materials for dosage forms. Natural polymers can be chemically modified to produce molecules with specific properties and formation of co-polymers or polymer mixtures provide new opportunities to develop innovative drug delivery systems. PMID:24597532

Scholtz, Jacques; Van der Colff, Jaco; Steenekamp, Jan; Stieger, Nicole; Hamman, Josias

2014-05-01

294

Detection of contaminating enzymatic activity in plant-derived recombinant biotechnology products.  

PubMed

Residual impurities in recombinantly produced protein biologics, such as host cell proteins (HCP), can potentially cause unwanted toxic or immunogenic responses in patients. Additionally, undetected impurities found in recombinant proteins used in cell culture may adversely impact basic research and biotechnology applications. Currently, the enzyme-linked immunosorbent assay (ELISA) is the standard for detection of residual HCP contamination in recombinantly produced biologics. Alternatively, two-dimensional liquid chromatography coupled to mass spectrometry is being developed as a tool for assessing this critical quality attribute. Both of these methods rely on the direct detection of HCPs and some previous knowledge of the contaminant. For contaminating enzymes, the mass level of the impurity may fall below the threshold of detection of these methods and underestimate the true impact. To address this point, here we demonstrate facile detection and characterization of contaminating phytase activity in rice-derived recombinant human serum albumin (rHSA) using a sensitive, label-free nuclear magnetic resonance (NMR) spectroscopy assay. We observed varying degrees of phytase contamination in biotechnology-grade rHSA from various manufacturers by monitoring the degradation of adenosine-5'-triphosphate and myo-inositol-1,2,3,4,5,6-hexakisphosphate by (31)P NMR. The observed lot-to-lot variability may result in irreproducible cell culture results and should be evaluated as a possible critical quality attribute in plant-derived biotherapeutics. PMID:25393810

Brinson, Robert G; Giulian, Gary G; Kelman, Zvi; Marino, John P

2014-12-01

295

Plant-derived foods for the attenuation of allergic airway inflammation.  

PubMed

Asthma is an allergy-mediated inflammatory disease characterised by infiltration of the airway with mast cells, lymphocytes, and eosinophils. The disease is induced by co-ordination of T-helper cell type 2 (Th2) cytokines and inflammatory signal molecules. Fruits and vegetables are a rich source of polyphenolic bioactive compounds, which have been observed to have health-promoting properties when consumed by humans. In particular, fruit-derived proanthocyanins and anthocyanins have been found to attenuate lung inflammation. Epidemiological studies have revealed correlations between fruit consumption and a lower prevalence of respiratory symptoms and lower incidence of non-specific lung diseases. In this review we summarise the current understanding of the pathophysiologic mechanism(s) involved in the development of allergic airway disease. We also review evidence of the beneficial effects of plant-derived foods, their components and metabolites in allergic airway inflammation arising from in vitro and rodent studies, epidemiological studies and human intervention trials. The mechanism, biological relevance and functional benefits, such as immune modulation (e.g. reduction in cytokine and eotaxin production), antioxidant ability, tissue remodelling and tight junction function are also discussed. PMID:23701570

Nyanhanda, Tafadzwa; Gould, Elaine M; Hurst, Roger D

2014-01-01

296

The relative anthelmintic efficacy of plant-derived cysteine proteinases on intestinal nematodes.  

PubMed

We examined the in vitro and in vivo efficacy of plant cysteine proteinases (CPs) derived from pineapple (Ananas comosus) and kiwi fruit (Actinidia deliciosa), and compared their efficacy as anthelmintics to the known effects of CPs from the latex of papaya (Carica papaya) against the rodent intestinal nematode, Heligmosomoides bakeri. Both fruit bromelain and stem bromelain had significant in vitro detrimental effects on H. bakeri but in comparison, actinidain from kiwi fruit had very little effect. However, in vivo trials indicated far less efficacy of stem bromelain and fruit bromelain than that expected from the in vitro experiments (24.5% and 22.4% reduction in worm burdens, respectively) against H. bakeri. Scanning electron microscopy revealed signs of cuticular damage on worms incubated in fruit bromelain, stem bromelain and actinidain, but this was far less extensive than on those incubated in papaya latex supernatant. We conclude that, on the basis of presently available data, CPs derived from pineapples and kiwi fruits are not suitable for development as novel anthelmintics for intestinal nematode infections. PMID:24176056

Luoga, W; Mansur, F; Buttle, D J; Duce, I R; Garnett, M C; Lowe, A; Behnke, J M

2015-03-01

297

Antiproliferative activity of essential oils derived from plants belonging to the Magnoliophyta division.  

PubMed

The essential oils obtained from different officinal plants of Lebanon, belonging to the Magnoliophyta division, have been tested for their antiproliferative activity on human erythroleukemic K562 cells. Satureja montana showed the most interesting biological activity in inhibiting the cell growth and inducing erythroid differentiation of K562 cells. The essential oil of Satureja montana was therefore analyzed using a GC/MS (gas chromatography/mass spectrometry) system in order to identify the major constituents and compare them with analysis performed on Satureja hortensis. We demonstrated that the essential oil composition varied with the species, the major constituent of Satureja hortensis being carvacrol (50.61%) and that of Satureja montana being alpha-terpineol (12.66%). In order to identify molecules possibly responsible for the biological activity, commercially available derivatives have been assayed on the K562 cell line. Satureja montana essential oil displayed different natural derivatives characterized by higher activity than those present in Satureja hortensis. The common active principles are alpha-pinene, gamma-terpinene, 4-terpineol, alpha-terpineol, tau-cadinene, tau-cadinol and caryophyllene. Both caryophyllene and alpha-terpineol showed important antiproliferative effects on K562 cells. PMID:16964395

Lampronti, Ilaria; Saab, Antoine M; Gambari, Roberto

2006-10-01

298

Molecular characterization of geminivirus-derived small RNAs in different plant species  

PubMed Central

DNA geminiviruses are thought to be targets of RNA silencing. Here, we characterize small interfering (si) RNAs—the hallmarks of silencing—associated with Cabbage leaf curl begomovirus in Arabidopsis and African cassava mosaic begomovirus in Nicotiana benthamiana and cassava. We detected 21, 22 and 24 nt siRNAs of both polarities, derived from both the coding and the intergenic regions of these geminiviruses. Genetic evidence showed that all the 24 nt and a substantial fraction of the 22 nt viral siRNAs are generated by the dicer-like proteins DCL3 and DCL2, respectively. The viral siRNAs were 5? end phosphorylated, as shown by phosphatase treatments, and methylated at the 3?-nucleotide, as shown by HEN1 miRNA methylase-dependent resistance to ?-elimination. Similar modifications were found in all types of endogenous and transgene-derived siRNAs tested, but not in a major fraction of siRNAs from a cytoplasmic RNA tobamovirus. We conclude that several distinct silencing pathways are involved in DNA virus-plant interactions. PMID:16421273

Akbergenov, Rashid; Si-Ammour, Azeddine; Blevins, Todd; Amin, Imran; Kutter, Claudia; Vanderschuren, Herve; Zhang, Peng; Gruissem, Wilhelm; Meins, Frederick; Hohn, Thomas; Pooggin, Mikhail M.

2006-01-01

299

New cytotoxic oxygenated sterols from marine bryozoan Bugula neritina.  

PubMed

Two new oxygenated sterols, 3?,24(S)-dihydroxycholesta-5,25-dien-7-one and 3?,25-dihydroxycholesta-5,23-dien-7-one, were isolated from the marine bryozoan Bugula neritina. Their chemical structures were established on the basis of spectroscopic analysis. Both compounds exhibited cytotoxicity to three human cancer cell lines (HepG2, HT-29 and NCI-H460), with IC?? values between 22.58 and 53.41 µg mL?ą. PMID:20602282

Yang, Fan; Zhang, Hong-Jun; Chen, Jian-Tao; Tang, Hai-Feng; Piao, Shu-Juan; Chen, Wan-Sheng; Lin, Hou-Wen

2011-09-01

300

Inhaled tobacco sterols: uptake by the lungs and disposition to selected organs of rats  

SciTech Connect

Tobacco sterols (cholesterol, beta-sitosterol, campesterol, and stigmasterol) are present in tobacco smoke and appear in plasma of mammals exposed to cigarette smoke. Because tobacco sterols may be important in the pathogenesis of smoking-induced lung and vascular diseases, we studied the pattern of deposition of cigarette sterols in the lungs and appearance of cigarette sterols in plasma and body organs of rats. After exposure to twenty 5 ml puffs of smoke from tobacco labeled with (4-/sup 14/C)cholesterol or beta-(4-/sup 14/C)sitosterol, rats were killed just after exposure (day 0) and on days 2, 5, 8, 11, 15, and 30, and the lungs and selected body organs analyzed for activity. We found that cigarette sterols are associated with particulates in cigarette smoke, deposited mostly in distal airspaces and parenchyma of the lungs, and appear in plasma and several body organs for more than 30 days after this single exposure to cigarette smoke. Bronchoalveolar lavage fluid contained relatively small amounts of radiolabel for only the first few days, suggesting that most of the sterols were rapidly incorporated in lung parenchyma. Because disorders of sterol metabolism have been implicated in a variety of diseases including atherosclerosis and cancer, the significance of tobacco sterols to human smoking-induced diseases deserves further study.

Holden, W.E.; Maier, J.M.; Liebler, J.M.; Malinow, M.R.

1988-08-01

301

Serum albumin promotes ATP-binding cassette transporter-dependent sterol uptake in yeast.  

PubMed

Sterol uptake in fungi is a multistep process that involves interaction between external sterols and the cell wall, incorporation of sterol molecules into the plasma membrane, and subsequent integration into intracellular membranes for turnover. ATP-binding cassette (ABC) transporters have been implicated in sterol uptake, but key features of their activity remain to be elucidated. Here, we apply fluorescent cholesterol (NBD-cholesterol) to monitor sterol uptake under anaerobic and aerobic conditions in two fungal species, Candida glabrata (Cg) and Saccharomyces cerevisiae (Sc). We found that in both fungal species, ABC transporter-dependent uptake of cholesterol under anaerobic conditions and in mutants lacking HEM1 gene is promoted in the presence of the serum protein albumin that is able to bind the sterol molecule. Furthermore, the C. glabrata ABC transporter CgAus1p expressed in S. cerevisiae requires the presence of serum or albumin for efficient cholesterol uptake. These results suggest that albumin can serve as sterol donor in ABC transporter-dependent sterol uptake, a process potentially important for growth of C. glabrata inside infected humans. PMID:25331273

Marek, Magdalena; Silvestro, Daniele; Fredslund, Maria D; Andersen, Tonni G; Pomorski, Thomas G

2014-12-01

302

A potential biochemical mechanism underlying the influence of sterol deprivation stress on Caenorhabditis elegans longevity  

Technology Transfer Automated Retrieval System (TEKTRAN)

To investigate the biochemical mechanism for sterol-mediated alteration in aging in Caenorhabditis elegans, we established sterol depletion conditions by treating worms with azacoprostane, which reduced mean lifespan of adult C. elegans by 35%. Proteomic analyses of egg proteins from treated and un...

303

Life history consequences of sterol availability in the aquatic keystone species Daphnia  

Microsoft Academic Search

The absence of essential biochemical nutrients, such as polyunsaturated fatty acids or sterols, has been considered as a mechanism\\u000a determining trophic interactions between the herbivore Daphnia and its phytoplankton food source. Here, we experimentally quantify the sensitivity of two Daphnia species to decreasing amounts of dietary sterols by measuring variations in life history traits. The two species Daphnia magna and

Dominik Martin-Creuzburg; Alexander Wacker; Eric von Elert

2005-01-01

304

Phylogenetic and biochemical evidence for sterol synthesis in the bacterium Gemmata obscuriglobus  

E-print Network

operon. Phylogenetic trees constructed for both enzymes show that the sterol pathway in bacteria produced by Gemmata suggest that this genus could retain the most ancient remnants of the sterol completely absent in prokaryotes (1). As a result, the presence of diverse steranes in ancient rocks is used

Brocks, Jochen J.

305

Identification and Biosynthetic Origins of Sterols in the Marine Bryozoan Bugula neritina  

E-print Network

of dietary sterols, while others are exclusively of dietary origin. The sterols of marine invertebrates have common in the more primi- tive invertebrates, and that cholesterol is present in greater relative of marine invertebrates with key lipids leads to enhanced growth rates.5-8 This report describes

Kerr, Russell G.

306

Rates of sterol synthesis and uptake in the major organs of the rat in vivo  

Microsoft Academic Search

This study was undertaken to determine the rates of sterol synthesis and uptake in the major organs of the female rat in vivo. At the mid-dark phase of the light cycle, control animals, animals in which hepatic sterol synthesis had been selectively inhibited by chylomicron infusion and animals in which the small intestine and liver had been surgically removed, were

Stephen D. Turley; John M. Andersen; John M. Dietsch

307

Effect of biosolids-derived triclosan and triclocarban on the colonization of plant roots by arbuscular mycorrhizal fungi.  

PubMed

Arbuscular mycorrhizal fungi (AMF) form a symbiotic relationship with the majority of crop plants. AMF provide plants with nutrients (e.g., P), modulate the effect of metal and pathogen exposure, and increase tolerance to moisture stress. The benefits of AMF to plant growth make them important to the development of sustainable agriculture. The land application of biosolids is becoming an increasingly common practice in sustainable agriculture, as a source of nutrients. However, biosolids have been found to contain numerous pharmaceutical and personal care products including antimicrobial chemicals such as triclosan and triclocarban. The potential risks that these two compounds may pose to plant-AMF interactions are poorly understood. The current study investigated whether biosolids-derived triclosan and triclocarban affect the colonization of the roots of lettuce and corn plants by AMF. Plants were grown in soil amended with biosolids that contained increasing concentrations of triclosan (0 to 307 ?g/g dw) or triclocarban (0 to 304 ?g/g dw). A relationship between the concentration of triclosan or triclocarban and colonization of plants roots by AMF was not observed. The presence of biosolids did not have a significant (p>0.05) effect on percent colonization of corn roots but had a significant, positive effect (p<0.05) on lettuce roots. Biosolids-derived triclosan and triclocarban did not inhibit the colonization of crop plant roots by AMF. PMID:25497682

Prosser, R S; Lissemore, L; Shahmohamadloo, R S; Sibley, P K

2015-03-01

308

Biochemical and molecular analysis of plants derived from embryogenic tissue cultures of napier grass (Pennisetum purpureum K. Schum).  

PubMed

We have investigated the extent of biochemical and molecular variation in 63 plants of napier grass (Pennisetum purpureum K. Schum.) regenerated from 3- to 24-week-old embryogenic callus cultures. The calli were derived from cultured basal segments of young leaves and immature inflorescences obtained from a single fieldgrown donor plant. The entire population was analyzed for the activity of 14 isozyme systems, but no qualitative variation was found at any of the loci examined. Similarly, no restriction fragment length polymorphisms (RFLPs) were detected in the mitochondrial, plastid and nuclear genomes in a representative sample of regenerated plants. Our results confirm earlier reports of the genetic uniformity of plants derived from somatic embryos and highlight their value both for clonal propagation and for genetic transformation. PMID:24202918

Shenoy, V B; Vasil, I K

1992-05-01

309

The mechanism of radical-trapping antioxidant activity of plant-derived thiosulfinates.  

PubMed

It has long been recognized that garlic and petiveria, two plants of the Allium genus--which also includes onions, leeks and shallots--possess great medicinal value. In recent times, the biological activities of extracts of these plants have been ascribed to the antioxidant properties of the thiosulfinate secondary metabolites allicin and S-benzyl phenylmethanethiosulfinate (BPT), respectively. Herein we describe our efforts to probe the mechanism of the radical-trapping antioxidant activity of these compounds, as well as S-propyl propanethiosulfinate (PPT), a saturated analog representative of the thiosulfinates that predominate in non-medicinal alliums. Our experimental results, which include thiosulfinate-inhibited autoxidations of the polyunsaturated fatty acid (ester) methyl linoleate, investigations of their decomposition kinetics, and radical clock experiments aimed at obtaining some quantitative insights into their reactions with peroxyl radicals, indicate that the radical-trapping activity of thiosulfinates is paralleled by their propensity to undergo Cope elimination to yield a sulfenic acid. Since sulfenic acids are transient species, we complement our experimental studies with the results of theoretical calculations aimed at understanding the radical-trapping behaviour of the sulfenic acids derived from allicin, BPT and PPT, and contrasting the predicted thermodynamics and kinetics of their reactions with those of the parent thiosulfinates. The calculations reveal that sulfenic acids have among the weakest O-H bonds known (ca. 70 kcal mol(-1)), and that their reactions with peroxyl radicals take place by a near diffusion-controlled proton-coupled electron transfer mechanism. As such, it is proposed that the abundance of a thiosulfinate in a given plant species, and the ease with which it undergoes Cope elimination to form a sulfenic acid, accounts for the differences in antioxidant activity, and perhaps medicinal value, of extracts of these plants. Interestingly, while the Cope elimination of 2-propenesulfenic acid from allicin is essentially irreversible, the analogous reaction of BPT is readily reversible. Thus, in the absence of chain-carrying peroxyl radicals (or other appropriately reactive trapping agent), BPT is reformed. PMID:21445384

Lynett, Philip T; Butts, Krista; Vaidya, Vipraja; Garrett, Graham E; Pratt, Derek A

2011-05-01

310

Boosting Crop Yields with Plant Steroids[W  

PubMed Central

Plant sterols and steroid hormones, the brassinosteroids (BRs), are compounds that exert a wide range of biological activities. They are essential for plant growth, reproduction, and responses to various abiotic and biotic stresses. Given the importance of sterols and BRs in these processes, engineering their biosynthetic and signaling pathways offers exciting potentials for enhancing crop yield. In this review, we focus on how alterations in components of sterol and BR metabolism and signaling or application of exogenous steroids and steroid inhibitors affect traits of agronomic importance. We also discuss areas for future research and identify the fine-tuning modulation of endogenous BR content as a promising strategy for crop improvement. PMID:22438020

Vriet, Cécile; Russinova, Eugenia; Reuzeau, Christophe

2012-01-01

311

Fungal genomes mining to discover novel sterol esterases and lipases as catalysts  

PubMed Central

Background Sterol esterases and lipases are enzymes able to efficiently catalyze synthesis and hydrolysis reactions of both sterol esters and triglycerides and due to their versatility could be widely used in different industrial applications. Lipases with this ability have been reported in the yeast Candida rugosa that secretes several extracellular enzymes with a high level of sequence identity, although different substrate specificity. This versatility has also been found in the sterol esterases from the ascomycetes Ophiostoma piceae and Melanocarpus albomyces. Results In this work we present an in silico search of new sterol esterase and lipase sequences from the genomes of environmental fungi. The strategy followed included identification and search of conserved domains from these versatile enzymes, phylogenetic studies, sequence analysis and 3D modeling of the selected candidates. Conclusions Six potential putative enzymes were selected and their kinetic properties and substrate selectivity are discussed on the basis of their similarity with previously characterized sterol esterases/lipases with known structures. PMID:24138290

2013-01-01

312

Annual Variation in the Sterol Content of Digitalis purpurea L. Seedlings 1  

PubMed Central

Seedings from a single lot of Digitalis purpurea L. seeds were germinated in batches over a period of 13 months. A total lipid extract was made which was resolved into esterified and unconjugated plus glycosylated sterol fractions. The amounts of sterol in each fraction and in the total were compared for seedlings germinated at different times of the year. The amount of esterified sterols reached a maximum value from March until June, and a low value from July until January. In January, a sharp increase began which lasted until March. Amounts of unconjugated and glycosylated sterols were elevated from March until June, low from July until October, and on the rise from November until March. These data correlate with an annual cycle in seed germination. The phase of maximum sterol content of seedlings is followed by a period of null germination. PMID:16659713

Jacobsohn, Myra K.; Jacobsohn, Gert M.

1976-01-01

313

Annual Variation in the Sterol Content of Digitalis purpurea L. Seedlings.  

PubMed

Seedings from a single lot of Digitalis purpurea L. seeds were germinated in batches over a period of 13 months. A total lipid extract was made which was resolved into esterified and unconjugated plus glycosylated sterol fractions. The amounts of sterol in each fraction and in the total were compared for seedlings germinated at different times of the year. The amount of esterified sterols reached a maximum value from March until June, and a low value from July until January. In January, a sharp increase began which lasted until March. Amounts of unconjugated and glycosylated sterols were elevated from March until June, low from July until October, and on the rise from November until March. These data correlate with an annual cycle in seed germination. The phase of maximum sterol content of seedlings is followed by a period of null germination. PMID:16659713

Jacobsohn, M K; Jacobsohn, G M

1976-10-01

314

Molecular cloning and biochemical characterization of a recombinant sterol 3-O-glucosyltransferase from Gymnema sylvestre R.Br. catalyzing biosynthesis of steryl glucosides.  

PubMed

Gymnema sylvestre R.Br., a pharmacologically important herb vernacularly called Gur-Mar (sugar eliminator), is widely known for its antidiabetic action. This property of the herb has been attributed to the presence of bioactive triterpene glycosides. Although some information regarding pharmacology and phytochemical profiles of the plant are available, no attempts have been made so far to decipher the biosynthetic pathway and key enzymes involved in biosynthesis of steryl glucosides. The present report deals with the identification and catalytic characterization of a glucosyltransferase, catalyzing biosynthesis of steryl glycosides. The full length cDNA (2572 bp) contained an open reading frame of 2106 nucleotides that encoded a 701 amino acid protein, falling into GT-B subfamily of glycosyltransferases. The GsSGT was expressed in Escherichia coli and biochemical characterization of the recombinant enzyme suggested its key role in the biosynthesis of steryl glucosides with catalytic preference for C-3 hydroxyl group of sterols. To our knowledge, this pertains to be the first report on cloning and biochemical characterization of a sterol metabolism gene from G. sylvestre R.Br. catalyzing glucosylation of a variety of sterols of biological origin from diverse organisms such as bacteria, fungi, and plants. PMID:25250339

Tiwari, Pragya; Sangwan, Rajender Singh; Asha; Mishra, B N; Sabir, Farzana; Sangwan, Neelam S

2014-01-01

315

Molecular Cloning and Biochemical Characterization of a Recombinant Sterol 3-O-Glucosyltransferase from Gymnema sylvestre R.Br. Catalyzing Biosynthesis of Steryl Glucosides  

PubMed Central

Gymnema sylvestre R.Br., a pharmacologically important herb vernacularly called Gur-Mar (sugar eliminator), is widely known for its antidiabetic action. This property of the herb has been attributed to the presence of bioactive triterpene glycosides. Although some information regarding pharmacology and phytochemical profiles of the plant are available, no attempts have been made so far to decipher the biosynthetic pathway and key enzymes involved in biosynthesis of steryl glucosides. The present report deals with the identification and catalytic characterization of a glucosyltransferase, catalyzing biosynthesis of steryl glycosides. The full length cDNA (2572?bp) contained an open reading frame of 2106 nucleotides that encoded a 701 amino acid protein, falling into GT-B subfamily of glycosyltransferases. The GsSGT was expressed in Escherichia coli and biochemical characterization of the recombinant enzyme suggested its key role in the biosynthesis of steryl glucosides with catalytic preference for C-3 hydroxyl group of sterols. To our knowledge, this pertains to be the first report on cloning and biochemical characterization of a sterol metabolism gene from G. sylvestre R.Br. catalyzing glucosylation of a variety of sterols of biological origin from diverse organisms such as bacteria, fungi, and plants. PMID:25250339

Sangwan, Rajender Singh; Asha; Mishra, B. N.; Sangwan, Neelam S.

2014-01-01

316

A trial of production of the plant-derived high-value protein in a plant factory  

PubMed Central

One of the ultimate goals of plant science is to test a hypothesis obtained by basic science and to apply it to agriculture and industry. A plant factory is one of the ideal systems for this trial. Environmental factors affect both plant yield and the accumulation of recombinant proteins for industrial applications within transgenic plants. However, there have been few reports studying plant productivity for recombinant protein in closed cultivation systems called plant factories. To investigate the effects of photosynthetic photon flux (PPF) on tomato fruit yield and the accumulation of recombinant miraculin, a taste-modifying glycoprotein, in transgenic tomato fruits, plants were cultivated at various PPFs from 100 to 400 (µmol m?2 s?1) in a plant factory. Miraculin production per unit of energy used was highest at PPF100, although miraculin production per unit area was highest at PPF300. The commercial productivity of recombinant miraculin in transgenic tomato fruits largely depended on light conditions in the plant factory. Our trial will be useful to consider the trade-offs between the profits from production of high-value materials in plants and the costs of electricity. PMID:21791976

Hirai, Tadayoshi; Hiwasa-Tanase, Kyoko; Goto, Eiji

2011-01-01

317

Evaluation of bioactive potential of an Aloe vera sterol extract.  

PubMed

We prepared a crude gel material from Aloe vera succulent leaf tissues. The ethanolic extract of lyophilized A. vera gel was used for the GC-MS analysis. Hexadecanoic acid (22.22%) was identified as major compound. Sitosterol and stigmasterol were found to be 2.89% and 2.1% in the extract. HPLC analysis was carried out to confirm the presence of stigmasterol. The concentration of sterol extract needed to scavenge DPPH free radical by 50% was calculated as 5.2 mg mL(-1). In the FRAP assay, the sterol extract showed significant hydroxyl radical scavenging in a dose-dependent manner (IC50 value 1.17 µg mL(-1)). Concentration of the sample required to reduce lipid peroxidation was found to be 4.18 µg mL(-1), and the extract also possessed acetylcholinesterase activity (IC50 - 5.26 µg mL(-1)). Catalase activity was 0.196 ?M H2 O2 decomposed min(-1) µg(-1) protein, whereas the peroxidase activity was 17.01 ?M of pyragallol oxidized min(-1) µg(-1) protein. The extract recorded higher activity against growth of S. greseus and C. albicans in the experiments carried out to determine antibacterial and antifungal activity, respectively. PMID:22899575

Bawankar, Raksha; Deepti, V C; Singh, Pooja; Subashkumar, Rathinasamy; Vivekanandhan, Govindasamy; Babu, Subramanian

2013-06-01

318

Gracilariopsis persica from Persian Gulf Contains Bioactive Sterols  

PubMed Central

Gracilariopsis Persica (Rhodophyta) is one of the most abundant algae, introduced newly from the Indian Ocean. In this study, the main sterols of the algae have been isolated and identified. Separation and purification of the compounds was carried out on silica gel and sephadex LH20 column chromatography (CC) and high performance liquid chromatography (HPLC) to obtain five pure compounds 1-5. Structural elucidation of the compounds was based on the data obtained from H-NMR, 13C-NMR, DEPT and Mass spectroscopy. The separated compounds from Gp. Persica were identified as 22-dehydrocholesterol (1), cholesterol (2), stigmasterol (3), ?-sitosterol (4) and fucosterol (5) based on the spectral data compared to those reported in literatures. Most of these sterols are noteworthy for their effectiveness in decreasing the plasma cholesterol, glucose and inflammation. The results of Brine Shrimp Cytotoxicity Assay indicated that the ethyl acetate extract of Gp. Persica showed a high cytotoxic effect against A. salina nauplii (LC50 = 4 ?g/mL). The methanol extract was no effective but the aqueous methanol extract was moderately effective (LC50 = 40 ?g/mL) compared to berberine hydrochloride as a positive control (LC50 = 26 ?g/mL). PMID:24250511

Saeidnia, Soodabeh; Permeh, Parisa; Gohari, Ahmad Reza; Mashinchian-Moradi, Ali

2012-01-01

319

A cytotoxic hydroperoxy sterol from the brown alga, Nizamuddinia zanardinii  

PubMed Central

Background The marine environment is a unique source of bioactive natural products, of which Nizamuddinia zanardinii is an important brown algae distributed in Oman Sea. Literature revealed that there is no report on phytochemistry and pharmacology of this valuable algae. Methods Bioguided fractionation of the methanolic extract of Nizamuddinia zanardinii, collected from Oman Sea, led to the isolation of a hydroperoxy sterol. Its structure was determined by analysis of the spectroscopic data as 24-hydroperoxy-24-vinyl cholesterol (HVC). In vitro cytotoxic activity of this compound was evaluated against HT29, MCF7, A549, HepG2 and MDBK cell lines. Results Although 24(R)-hydroproxy-24-vinylcholesterol has been previously reported from Sargassum and Padina species, it is the first report on the presence of this compound from N. zanardinii. This compound exhibited cytotoxicity in all cell lines (IC50, 3.62, 9.09, 17.96, 32.31 and 37.31??g/mL respectively). HVC was also evaluated for apoptotic activity and demonstrated positive results in terminal deoxynucleotidyl transferase dUTP Nick End labeling (TUNEL) assay suggesting it a candidate for further apoptotic studies. Conclusions Nizamuddinia zanardinii, a remarkable brown algae of Oman Sea, is a good source of hydroproxy sterols with promising cytotoxic on various cell lines particularly human colon adenocarcinoma. PMID:23497504

2013-01-01

320

Evaluation of the anti-Listeria potentials of some plant-derived triterpenes  

PubMed Central

Background Listeriosis is a fatal disease caused by pathogenic Listeria bacteria and it is most prevalent in immune-compromised individuals. The increase in numbers of immune-compromised individuals against a background of Listeria antibiotic resistance, limits listeriosis treatment options. This therefore calls for research into substitute treatments, of which, medicinal plants derived compounds offer a viable alternative. Methods The broth microdilution assay was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of three plant triterpenes namely 3?-hydroxylanosta-9,24-dien-21-oic acid, methyl-3?-hydroxylanosta-9,24-dien-21-oate and 3?-acetylursolic acid, against Listeria monocytogenes, Listeria ivanovii and Listeria grayi species. The chequerboard method was used to assess the interactions between the triterpenes and conventional antibiotics: ampicillin, neomycin, gentamicin and penicillin G. The lactate dehydrogenase membrane damage method was used to assess the triterpenes’ membrane damaging potentials against the Listeria bacteria. Results The triterpenes’ MIC values were found to range from 0.185 to 1.67 mg/ml while, the MBC determination assay results revealed that the test triterpenes were bacteriostatic against the Listeria bacteria. The interactions involving 3?-hydroxylanosta-9,24-dien-21-oic acid were mainly additive with ampicillin and synergistic with neomycin, gentamicin and penicillin G. The interactions involving methyl-3?-hydroxylanosta-9,24-dien-21-oate were mainly antagonistic with ampicillin, indifferent with neomycin, ranging from synergistic to indifference with gentamicin and synergistic with penicillin G. The interactions involving 3?-acetylursolic acid were mainly indifferent with ampicillin, synergistic with neomycin and gentamicin while ranging between synergistic and additive with penicillin G. The low levels of cytosolic lactate dehydrogenase released from the cells treated with 4× MIC concentration of the triterpenes in comparison to that of cells treated with 3% Triton X-100 proved that membrane damage was not the mode of action of the triterpenes. Conclusion This study therefore shows the potential that these plant triterpenes have in listeriosis chemotherapy especially as shown by the favourable interactions they had with penicillin G, one of the antibiotics of choice in listeriosis treatment. PMID:25056181

2014-01-01

321

Fecal sterols, seasonal variability, and probable sources along the ring of cenotes, Yucatan, Mexico.  

PubMed

Rapid development in Yucatan has had a dramatic impact on the environment, especially the water supply. Groundwater is the only source of water in Yucatan, since surface water is virtually absent due to the karstic nature of the soil. The ring of cenotes (RC) is a geological feature which functions as a source of water and as nodes in the underground river system that canalizes water towards the coast. Numerous productive and domestic activities take place around the RC in the absence of wastewater treatment or sewage systems. Consequently, a number of researchers have hypothesized that pollutants could migrate from the land surface to the underlying aquifer and, eventually, to the coast. Therefore, the present study investigates the relationship among sources of fecal sterols and their levels in cenotes, using the expected levels of fecal sterols obtained by a spatial analysis of the sources and a Pollution Source Index. Accordingly, expected levels are compared with the detected levels of fecal sterols in 5 areas around the RC. Regarding levels, observed during a sampling campaign carried out along the RC during September 2011 (rainy season) and May 2012 (dry season), varied from low to high concentrations of sterols (0.5-2396.42 ?g g(-1)) and fecal sterols (0.3-1690.18 ?g g(-1)). These concentrations showed no relationship between neighboring cenotes, where similar fecal sterol concentrations or gradients were expected. When comparing expected fecal sterols levels with the detected ones, only two of the five analyzed areas concur, suggesting that no clear relationship exists among sources and fecal sterols levels at the regional scale. Multivariate analysis showed that fecal sterols were associated with sterols and fine grain particulates during the rainy season, which suggests co-transport. During the dry season, fecal sterols associated with fine grain particulate and organic matter, which indicates a change to a deposition phenomenon. These findings indicate that defining a relationship among sources and fecal sterols levels is highly difficult and this could be the result of the absorption or migration through an intricate conduit, crack, or fracture karst system. Nevertheless, the "source-levels approach", used in this study, was consistent for the northeast edge and the middle western part of the RC. New and more extensive research should be done to assess the environmental fate of fecal sterols, especially considering the intricate karstic system and its compound retention capacity. PMID:25282019

Arcega-Cabrera, F; Velázquez-Tavera, N; Fargher, L; Derrien, M; Noreńa-Barroso, E

2014-11-01

322

Fecal sterols, seasonal variability, and probable sources along the ring of cenotes, Yucatan, Mexico  

NASA Astrophysics Data System (ADS)

Rapid development in Yucatan has had a dramatic impact on the environment, especially the water supply. Groundwater is the only source of water in Yucatan, since surface water is virtually absent due to the karstic nature of the soil. The ring of cenotes (RC) is a geological feature which functions as a source of water and as nodes in the underground river system that canalizes water towards the coast. Numerous productive and domestic activities take place around the RC in the absence of wastewater treatment or sewage systems. Consequently, a number of researchers have hypothesized that pollutants could migrate from the land surface to the underlying aquifer and, eventually, to the coast. Therefore, the present study investigates the relationship among sources of fecal sterols and their levels in cenotes, using the expected levels of fecal sterols obtained by a spatial analysis of the sources and a Pollution Source Index. Accordingly, expected levels are compared with the detected levels of fecal sterols in 5 areas around the RC. Regarding levels, observed during a sampling campaign carried out along the RC during September 2011 (rainy season) and May 2012 (dry season), varied from low to high concentrations of sterols (0.5-2396.42 ?g g- 1) and fecal sterols (0.3-1690.18 ?g g- 1). These concentrations showed no relationship between neighboring cenotes, where similar fecal sterol concentrations or gradients were expected. When comparing expected fecal sterols levels with the detected ones, only two of the five analyzed areas concur, suggesting that no clear relationship exists among sources and fecal sterols levels at the regional scale. Multivariate analysis showed that fecal sterols were associated with sterols and fine grain particulates during the rainy season, which suggests co-transport. During the dry season, fecal sterols associated with fine grain particulate and organic matter, which indicates a change to a deposition phenomenon. These findings indicate that defining a relationship among sources and fecal sterols levels is highly difficult and this could be the result of the absorption or migration through an intricate conduit, crack, or fracture karst system. Nevertheless, the “source-levels approach”, used in this study, was consistent for the northeast edge and the middle western part of the RC. New and more extensive research should be done to assess the environmental fate of fecal sterols, especially considering the intricate karstic system and its compound retention capacity.

Arcega-Cabrera, F.; Velázquez-Tavera, N.; Fargher, L.; Derrien, M.; Noreńa-Barroso, E.

2014-11-01

323

Characterization of transgenic plants derived from hairy roots of Hyoscyamus muticus  

Microsoft Academic Search

Mature plants were regenerated via protoplasts fromAgrobacterium rhizogenes-transformed root cultures ofHyoscyamus muticus L., and chemical analyses were performed on 34 individual plants. The regenerated plants showed strong phenotypic differences from clone to clone as well as from the control plants. Polymerase chain reaction studies revealed that the plants exhibiting the strongest phenotypic alterations contained therol (A, B and C) genes,

N. Sevón; B. Dräger; R. Hiltunen; K.-M. Oksman-Caldentey

1997-01-01

324

Novel composition of mitochondrial genomes in Petunia somatic hybrids derived from cytoplasmic male sterile and fertile plants  

Microsoft Academic Search

The mitochondrial genomes of petunia somatic hybrid plants, which were derived from the fusion of male fertile P. hybrida protoplasts with cytoplasmic male sterile P. parodii protoplasts, were analyzed by endonuclease restriction and Southern blot hybridization analyses. We studied sterile and fertile somatic hybrids to address two main questions. First, is there any correlation between the mitochondrial DNA restriction banding

Maury L. Boeshore; Irit Lifshitz; Maureen R. Hanson; Shamay Izhar

1983-01-01

325

Toward a Quarter Century of Pathogen-Derived Resistance and Practical Approaches to Plant Virus Disease Control  

Microsoft Academic Search

The concept of pathogen-derived resistance (PDR) describes the use of genetic elements from a pathogen’s own genome to confer resistance in an otherwise susceptible host via genetic engineering [J. Theor. Biol. 113 (1985) 395]. Illustrated with the bacteriophage Q? in Escherichia coli, this strategy was conceived as a broadly applicable approach to engineer resistance against pathogens. For plant viruses, the

J. Gottula; M. Fuchs

2009-01-01

326

The Endocannabinoid System and Plant-Derived Cannabinoids in Diabetes and Diabetic Complications  

PubMed Central

Oxidative stress and inflammation play critical roles in the development of diabetes and its complications. Recent studies provided compelling evidence that the newly discovered lipid signaling system (ie, the endocannabinoid system) may significantly influence reactive oxygen species production, inflammation, and subsequent tissue injury, in addition to its well-known metabolic effects and functions. The modulation of the activity of this system holds tremendous therapeutic potential in a wide range of diseases, ranging from cancer, pain, neurodegenerative, and cardiovascular diseases to obesity and metabolic syndrome, diabetes, and diabetic complications. This review focuses on the role of the endocannabinoid system in primary diabetes and its effects on various diabetic complications, such as diabetic cardiovascular dysfunction, nephropathy, retinopathy, and neuropathy, particularly highlighting the mechanisms beyond the metabolic consequences of the activation of the endocannabinoid system. The therapeutic potential of targeting the endocannabinoid system and certain plant-derived cannabinoids, such as cannabidiol and ?9-tetrahydrocannabivarin, which are devoid of psychotropic effects and possess potent anti-inflammatory and/or antioxidant properties, in diabetes and diabetic complications is also discussed. PMID:22155112

Horváth, Béla; Mukhopadhyay, Partha; Haskó, György; Pacher, Pál

2012-01-01

327

Metabolism of a plant derived galactose?containing polysaccharide by Bifidobacterium breve UCC2003  

PubMed Central

Summary In this study, we describe the functional characterization of the Bifidobacterium breve UCC2003 gal locus, which is dedicated to the utilization of galactan, a plant?derived polysaccharide. Using a combination of molecular approaches we conclude that the galA gene of B. breve UCC2003 encodes a ??1,4?endogalactanase producing galacto?oligosaccharides, which are specifically internalized by an ABC transport system, encoded by galBCDE, and which are then hydrolysed to galactose moieties by a dedicated intracellular ??galactosidase, specified by galG. The generated galactose molecules are presumed to be fed into the fructose?6?phosphate phosphoketolase pathway via the Leloir pathway, thereby allowing B. breve UCC2003 to use galactan as its sole carbon and energy source. In addition to these findings we demonstrate that GalR is a LacI?type DNA?binding protein, which not only appears to control transcription of the galCDEGR operon, but also that of the galA gene. PMID:21375716

O'Connell Motherway, Mary; Fitzgerald, Gerald F.; van Sinderen, Douwe

2011-01-01

328

Plant-derived polysaccharide supplements inhibit dextran sulfate sodium-induced colitis in the rat.  

PubMed

Several plant-derived polysaccharides have been shown to have anti-inflammatory activity in animal models. Ambrotose complex and Advanced Ambrotose are dietary supplements that include aloe vera gel, arabinogalactan, fucoidan, and rice starch, all of which have shown such activity. This study was designed to evaluate these formulations against dextran sulfate sodium (DSS)-induced colitis in rats and to confirm their short-term safety after 14 days of daily dosing. Rats were dosed daily orally with vehicle, Ambrotose or Advanced Ambrotose. On day six groups of rats received tap water or 5% Dextran Sulfate sodium. Ambrotose and Advanced Ambrotose significantly lowered the disease scores and partially prevented the shortening of colon length. An increase in monocyte count was induced by dextran sulfate sodium and inhibited by Ambrotose and Advanced Ambrotose. There were no observable adverse effects after 14-day daily doses. The mechanism of action of the formulations against DSS-induced colitis may be related to its effect on monocyte count. PMID:19513840

Koetzner, Lee; Grover, Gary; Boulet, Jamie; Jacoby, Henry I

2010-05-01

329

The endocannabinoid system and plant-derived cannabinoids in diabetes and diabetic complications.  

PubMed

Oxidative stress and inflammation play critical roles in the development of diabetes and its complications. Recent studies provided compelling evidence that the newly discovered lipid signaling system (ie, the endocannabinoid system) may significantly influence reactive oxygen species production, inflammation, and subsequent tissue injury, in addition to its well-known metabolic effects and functions. The modulation of the activity of this system holds tremendous therapeutic potential in a wide range of diseases, ranging from cancer, pain, neurodegenerative, and cardiovascular diseases to obesity and metabolic syndrome, diabetes, and diabetic complications. This review focuses on the role of the endocannabinoid system in primary diabetes and its effects on various diabetic complications, such as diabetic cardiovascular dysfunction, nephropathy, retinopathy, and neuropathy, particularly highlighting the mechanisms beyond the metabolic consequences of the activation of the endocannabinoid system. The therapeutic potential of targeting the endocannabinoid system and certain plant-derived cannabinoids, such as cannabidiol and ?9-tetrahydrocannabivarin, which are devoid of psychotropic effects and possess potent anti-inflammatory and/or antioxidant properties, in diabetes and diabetic complications is also discussed. PMID:22155112

Horváth, Béla; Mukhopadhyay, Partha; Haskó, György; Pacher, Pál

2012-02-01

330

Dynamic molecular structure of plant biomass-derived black carbon (biochar)  

SciTech Connect

Char black carbon (BC), the solid residue of incomplete combustion, is continuously being added to soils and sediments due to natural vegetation fires, anthropogenic pollution, and new strategies for carbon sequestration ('biochar'). Here we present a molecular-level assessment of the physical organization and chemical complexity of biomass-derived chars and, specifically, that of aromatic carbon in char structures. BET-N{sub 2} surface area, X-ray diffraction (XRD), synchrotron-based Near-edge X-ray Absorption Fine Structure (NEXAFS), and Fourier transform infrared (FT-IR) spectroscopy are used to show how two plant materials (wood and grass) undergo analogous, but quantitatively different physical-chemical transitions as charring temperature increases from 100 to 700 C. These changes suggest the existence of four distinct categories of char consisting of a unique mixture of chemical phases and physical states: (i) in transition chars the crystalline character of the precursor materials is preserved, (ii) in amorphous chars the heat-altered molecules and incipient aromatic polycondensates are randomly mixed, (iii) composite chars consist of poorly ordered graphene stacks embedded in amorphous phases, and (iv) turbostratic chars are dominated by disordered graphitic crystallites. The molecular variations among the different char categories translate into differences in their ability to persist in the environment and function as environmental sorbents.

Keiluweit, M.; Nico, P.S.; Johnson, M.G.; Kleber, M.

2009-11-15

331

Electron Beam Lithography Using Highly Sensitive Negative Type of Plant-Based Resist Material Derived from Biomass on Hardmask Layer  

NASA Astrophysics Data System (ADS)

We investigated electron beam (EB) lithography using a novel highly sensitive negative type of plant-based resist material derived from biomass on a hardmask layer for trilayer processes. The chemical design concept for using the plant-based resist material with glucose and dextrin derivatives was first demonstrated in the EB lithography. The 1 µm line patterning images with highly efficient crosslinking properties and low film thickness shrinkage were provided under specific process conditions of EB lithography. The results shown reveal that the alpha-linked disaccharide formed by a 1,1-glucoside bond between two glucose units in dextrin derivatives was an important factor in controlling the highly sensitive EB patterning and developer properties.

Takei, Satoshi; Oshima, Akihiro; Sekiguchi, Atsushi; Yanamori, Naomi; Kashiwakura, Miki; Kozawa, Takahiro; Tagawa, Seiichi

2011-10-01

332

Evidence for metabolic and functional discrimination of sterols by Phytophthora cactorum  

PubMed Central

When fed 10 ppm of one of the following sterols: cholesterol (cholest-5-en-3?-ol), wingsterol (21-isopentylcholesterol), desmosterol [cholesta-5,24(25)-dien-3?-ol], 24-methylenecholesterol [ergosta-5,24(28)-dien-3?-ol], or fucosterol [stigmasta-5,24(28)-dien-3?-ol], the pathogenic fungus Phytophthora cactorum, which is naturally unable to epoxidize squalene, accumulated each of the test compounds to similar levels. Fucosterol, the only sterol metabolized, was reduced to yield 24-ethylcholesterol. All the sterols tested induced the formation of sex structures. Fertilization and subsequent maturation of oospores capable of germination occurred only with the naturally occurring sterols. Wingsterol treatments resulted in aborted oospores. None of the sterols tested was inhibitory to growth, measured as changes in the 21-day mycelial dry weight. The results are consistent with the view that the accumulated sterol functions to regulate the life cycle of P. cactorum. However, the metabolism and kinds of recognition of the sterol molecule, in terms of uptake and effects on growth and induction of the various sexual events, contrast sharply with what is known for other oomycetous fungi such as Achlya and Saprolegnia. This implies that the evolutionary histories of the Oomycetes may be different. Images PMID:16593322

Nes, W. David; Stafford, Allen E.

1983-01-01

333

Constitutive expression of transgenes encoding derivatives of the synthetic antimicrobial peptide BP100: impact on rice host plant fitness  

PubMed Central

Background The Biopeptide BP100 is a synthetic and strongly cationic ?-helical undecapeptide with high, specific antibacterial activity against economically important plant-pathogenic bacteria, and very low toxicity. It was selected from a library of synthetic peptides, along with other peptides with activities against relevant bacterial and fungal species. Expression of the BP100 series of peptides in plants is of major interest to establish disease-resistant plants and facilitate molecular farming. Specific challenges were the small length, peptide degradation by plant proteases and toxicity to the host plant. Here we approached the expression of the BP100 peptide series in plants using BP100 as a proof-of-concept. Results Our design considered up to three tandemly arranged BP100 units and peptide accumulation in the endoplasmic reticulum (ER), analyzing five BP100 derivatives. The ER retention sequence did not reduce the antimicrobial activity of chemically synthesized BP100 derivatives, making this strategy possible. Transformation with sequences encoding BP100 derivatives (bp100der) was over ten-fold less efficient than that of the hygromycin phosphotransferase (hptII) transgene. The BP100 direct tandems did not show higher antimicrobial activity than BP100, and genetically modified (GM) plants constitutively expressing them were not viable. In contrast, inverted repeats of BP100, whether or not elongated with a portion of a natural antimicrobial peptide (AMP), had higher antimicrobial activity, and fertile GM rice lines constitutively expressing bp100der were produced. These GM lines had increased resistance to the pathogens Dickeya chrysanthemi and Fusarium verticillioides, and tolerance to oxidative stress, with agronomic performance comparable to untransformed lines. Conclusions Constitutive expression of transgenes encoding short cationic ?-helical synthetic peptides can have a strong negative impact on rice fitness. However, GM plants expressing, for example, BP100 based on inverted repeats, have adequate agronomic performance and resistant phenotypes as a result of a complex equilibrium between bp100der toxicity to plant cells, antimicrobial activity and transgene-derived plant stress response. It is likely that these results can be extended to other peptides with similar characteristics. PMID:22947243

2012-01-01

334

Reliance on prey-derived nitrogen by the carnivorous plant Drosera rotundifolia decreases with increasing nitrogen deposition.  

PubMed

• Carnivory in plants is presumed to be an adaptation to a low-nutrient environment. Nitrogen (N) from carnivory is expected to become a less important component of the N budget as root N availability increases. • Here, we investigated the uptake of N via roots versus prey of the carnivorous plant Drosera rotundifolia growing in ombrotrophic bogs along a latitudinal N deposition gradient through Sweden, using a natural abundance stable isotope mass balance technique. • Drosera rotundifolia plants receiving the lowest level of N deposition obtained a greater proportion of N from prey (57%) than did plants on bogs with higher N deposition (22% at intermediate and 33% at the highest deposition). When adjusted for differences in plant mass, this pattern was also present when considering total prey N uptake (66, 26 and 26 ?g prey N per plant at the low, intermediate and high N deposition sites, respectively). The pattern of mass-adjusted root N uptake was opposite to this (47, 75 and 86 ?g N per plant). • Drosera rotundifolia plants in this study switched from reliance on prey N to reliance on root-derived N as a result of increasing N availability from atmospheric N deposition. PMID:22506640

Millett, J; Svensson, B M; Newton, J; Rydin, H

2012-07-01

335

Zinc Finger Transcription Factors Displaced SREBP Proteins as the Major Sterol Regulators during Saccharomycotina Evolution  

PubMed Central

In most eukaryotes, including the majority of fungi, expression of sterol biosynthesis genes is regulated by Sterol-Regulatory Element Binding Proteins (SREBPs), which are basic helix-loop-helix transcription activators. However, in yeasts such as Saccharomyces cerevisiae and Candida albicans sterol synthesis is instead regulated by Upc2, an unrelated transcription factor with a Gal4-type zinc finger. The SREBPs in S. cerevisiae (Hms1) and C. albicans (Cph2) have lost a domain, are not major regulators of sterol synthesis, and instead regulate filamentous growth. We report here that rewiring of the sterol regulon, with Upc2 taking over from SREBP, likely occurred in the common ancestor of all Saccharomycotina. Yarrowia lipolytica, a deep-branching species, is the only genome known to contain intact and full-length orthologs of both SREBP (Sre1) and Upc2. Deleting YlUPC2, but not YlSRE1, confers susceptibility to azole drugs. Sterol levels are significantly reduced in the YlUPC2 deletion. RNA-seq analysis shows that hypoxic regulation of sterol synthesis genes in Y. lipolytica is predominantly mediated by Upc2. However, YlSre1 still retains a role in hypoxic regulation; growth of Y. lipolytica in hypoxic conditions is reduced in a Ylupc2 deletion and is abolished in a Ylsre1/Ylupc2 double deletion, and YlSre1 regulates sterol gene expression during hypoxia adaptation. We show that YlSRE1, and to a lesser extent YlUPC2, are required for switching from yeast to filamentous growth in hypoxia. Sre1 appears to have an ancestral role in the regulation of filamentation, which became decoupled from its role in sterol gene regulation by the arrival of Upc2 in the Saccharomycotina. PMID:24453983

Maguire, Sarah L.; Wang, Can; Holland, Linda M.; Brunel, François; Neuvéglise, Cécile; Nicaud, Jean-Marc; Zavrel, Martin; White, Theodore C.; Wolfe, Kenneth H.; Butler, Geraldine

2014-01-01

336

Comparison of Sterol Biomarkers for Sewage with other Measures in Victoria Harbour, B.C., Canada  

NASA Astrophysics Data System (ADS)

A lipid biomarker survey was conducted in Victoria Harbour, Canada, to compare the distribution of sewage-derived organic matter with existing results from bacterial studies. Previous surveys [Miller (1993) Report prepared by Capital Regional District Engineering Department, Victoria, B.C. Canada and Miller et al. (1995) Report prepared by CRD Environmental Services Group and Aquatic Science Consultants Ltd., B.C., Canada] of sewage contamination in the harbour were based principally on infrequent faecal coliform counts. The use of lipid biomarkers to determine time-averaged concentrations of sewage components in sediments may be a more appropriate method for defining areas where sewage is causing environmental or human health risks. 5?-Coprostanol was measured together with other sterols, fatty acids and fatty alcohols. Generally, sewage contamination shown by these lipid biomarkers was coincident with high faecal coliform counts from previous studies. However, this survey suggests, contrary to faecal coliform counts, that Portage Inlet was a region where sewage had accumulated in the sediments, possibly due to nearby overflow facilities or tidal pumping. Although the bacterial counts were low, sewage-derived organic matter was accumulating in the slack areas. In sediments of the Gorge and West Bay there were low faecal biomarker concentrations; this was probably due to the strong tidal currents which do not allow faecal matter to settle in sediments. Faecal coliform counts, however, indicated poor water quality in these same regions but this probably reflects fresh discharges passing through this area without leading to settlement.

Mudge, S. M.; Lintern, D. Gwyn

1999-01-01

337

Effects of singlet oxygen on membrane sterols in the yeast Saccharomyces cerevisiae.  

PubMed

Photodynamic treatment of the yeast Saccharomyces cerevisiae with the singlet oxygen sensitizer toluidine blue and visible light leads to rapid oxidation of ergosterol and accumulation of oxidized ergosterol derivatives in the plasma membrane. The predominant oxidation product accumulated was identified as 5alpha, 6alpha-epoxy-(22E)-ergosta-8,22-dien-3beta,7a lpha-diol (8-DED). 9(11)-dehydroergosterol (DHE) was identified as a minor oxidation product. In heat inactivated cells ergosterol is photooxidized to ergosterol epidioxide (EEP) and DHE. Disrupted cell preparations of S. cerevisiae convert EEP to 8-DED, and this activity is abolished in a boiled control indicating the presence of a membrane associated enzyme with an EEP isomerase activity. Yeast selectively mobilizes ergosterol from the intracellular sterol ester pool to replenish the level of free ergosterol in the plasma membrane during singlet oxygen oxidation. The following reaction pathway is proposed: singlet oxygen-mediated oxidation of ergosterol leads to mainly the formation of EEP, which is enzymatically rearranged to 8-DED. Ergosterol 7-hydroperoxide, a known minor product of the reaction of singlet oxygen with ergosterol, is formed at a much lower rate and decomposes to give DHE. Changes of physical properties of the plasma membrane are induced by depletion of ergosterol and accumulation of polar derivatives. Subsequent permeation of photosensitizer through the plasma membrane into the cell leads to events including impairment of mitochondrial function and cell inactivation. PMID:10712590

Böcking, T; Barrow, K D; Netting, A G; Chilcott, T C; Coster, H G; Höfer, M

2000-03-01

338

Gas chromatography-mass spectrometry study of sterols from Pinus elliotti tissues.  

NASA Technical Reports Server (NTRS)

A comparative study of the sterol components of slash pine (Pinus elliotti) callus tissue cultures, seeds, and seedlings was carried out using GC-MS techniques. Cholesterol, desmosterol, campesterol, stigmasterol, sitosterol and cycloeucalenol were identified in all tissues while lophenol and 24-methylenelophenol were identified in only the seed and seedlings. 24-Ethylidenelophenol was detected in trace concentrations in only the seedlings. Sitosterol was the predominant sterol component, i.e., 80.8, 38.1 and 47.8% of the tissue culture, seed and seedling sterols, respectively.

Laseter, J. L.; Evans, R.; Weete, J. D.; Walkinshaw, C. H.

1973-01-01

339

Regulation of Sterol Transport between Membranes and NPC2†  

PubMed Central

Niemann-Pick disease type C (NPC) is caused by defects in either the NPC1 or NPC2 gene and is characterized by accumulation of cholesterol and glycolipids in the late endosome/lysosome compartment. NPC2 is an intralysosomal protein that binds cholesterol in vitro. Previous studies demonstrated rapid rates of cholesterol transfer from NPC2 to model membranes [Cheruku, S. R., et al. (2006) J. Biol. Chem. 281, 31594–31604]. To model the potential role of NPC2 as a lysosomal cholesterol export protein, in this study we used fluorescence spectroscopic approaches to examine cholesterol transfer from membranes to NPC2, assessing the rate, mechanism, and regulation of this transport step. In addition, we examined the effect of NPC2 on the rate and kinetic mechanism of intermembrane sterol transport, to model the movement of cholesterol from internal lysosomal membranes to the limiting lysosomal membrane. The results support the hypothesis that NPC2 plays an important role in endo/lysosomal cholesterol trafficking by markedly accelerating the rates of cholesterol transport. Rates of sterol transfer from and between membranes were increased by as much as 2 orders of magnitude by NPC2. The transfer studies indicate that the mechanism of NPC2 action involves direct interaction of the protein with membranes. Such interactions were observed directly using FTIR spectroscopy and protein tryptophan spectral shifts. Additionally, cholesterol transfer by NPC2 was found to be greatly enhanced by the unique lysosomal phospholipid lyso-bisphosphatidic acid (LBPA), suggesting an important role for LBPA in NPC2-mediated cholesterol trafficking. PMID:18823126

Xu, Zhi; Farver, William; Kodukula, Sarala; Storch, Judith

2015-01-01

340

Reduction of Salmonella on turkey breast cutlets by plant-derived compounds.  

PubMed

The foodborne illnesses associated with poultry meat due to Salmonella are a major concern in the United States. In this study, the antimicrobial efficacy of carvacrol, eugenol, thyme essential oil, and trans-cinnamaldehyde was determined against different Salmonella serotypes in vitro and on turkey breast cutlets. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of antimicrobial agents were determined using a microdilution colorimetric assay. Carvacrol was the most effective antimicrobial agent since it exhibited the lowest MIC and MBC (0.313??L/mL, respectively) in culture media against Salmonella. Turkey breast cutlets inoculated with Salmonella Enteritidis, Salmonella Heidelberg, and Salmonella Typhimurium were dip treated with different concentrations (0.5, 1, 2, and 5% vol/vol) of carvacrol, eugenol, thyme essential oil, and trans-cinnamaldehyde for 2?min. Samples were analyzed after 24-h storage at 4°C for recovery of Salmonella. Significant reductions of Salmonella (p?0.05) on turkey breast cutlets were obtained with 1, 2, and 5% treatments. These compounds exhibited a concentration-dependent response on turkey breast cutlets against Salmonella. For example, 1% carvacrol resulted in 1.0 log colony-forming units (CFU)/g reduction of Salmonella whereas 5% carvacrol caused 2.6 log CFU/g reduction. Based on its efficacy in the 2-min dip study, carvacrol was selected for 30-s and 60-s dip treatments of Salmonella-inoculated turkey breast cutlets. Dipping turkey breast cutlets in 5% carvacrol for 30?s and 60?s resulted in 1.0 and 1.8 log reductions of Salmonella (p?0.05), respectively. None of the antimicrobial agents caused any changes in the meat pH (p>0.05). In conclusion, this study revealed that plant-derived compounds such as carvacrol can reduce Salmonella on turkey breast cutlets without changing the pH of meat. PMID:25405806

Nair, Divek V T; Nannapaneni, Rama; Kiess, Aaron; Schilling, Wes; Sharma, Chander Shekhar

2014-12-01

341

Classification of Plant Associated Bacteria Using RIF, a Computationally Derived DNA Marker  

PubMed Central

A DNA marker that distinguishes plant associated bacteria at the species level and below was derived by comparing six sequenced genomes of Xanthomonas, a genus that contains many important phytopathogens. This DNA marker comprises a portion of the dnaA replication initiation factor (RIF). Unlike the rRNA genes, dnaA is a single copy gene in the vast majority of sequenced bacterial genomes, and amplification of RIF requires genus-specific primers. In silico analysis revealed that RIF has equal or greater ability to differentiate closely related species of Xanthomonas than the widely used ribosomal intergenic spacer region (ITS). Furthermore, in a set of 263 Xanthomonas, Ralstonia and Clavibacter strains, the RIF marker was directly sequenced in both directions with a success rate approximately 16% higher than that for ITS. RIF frameworks for Xanthomonas, Ralstonia and Clavibacter were constructed using 682 reference strains representing different species, subspecies, pathovars, races, hosts and geographic regions, and contain a total of 109 different RIF sequences. RIF sequences showed subspecific groupings but did not place strains of X. campestris or X. axonopodis into currently named pathovars nor R. solanacearum strains into their respective races, confirming previous conclusions that pathovar and race designations do not necessarily reflect genetic relationships. The RIF marker also was sequenced for 24 reference strains from three genera in the Enterobacteriaceae: Pectobacterium, Pantoea and Dickeya. RIF sequences of 70 previously uncharacterized strains of Ralstonia, Clavibacter, Pectobacterium and Dickeya matched, or were similar to, those of known reference strains, illustrating the utility of the frameworks to classify bacteria below the species level and rapidly match unknown isolates to reference strains. The RIF sequence frameworks are available at the online RIF database, RIFdb, and can be queried for diagnostic purposes with RIF sequences obtained from unknown strains in both chromatogram and FASTA format. PMID:21533033

Schneider, Kevin L.; Marrero, Glorimar; Alvarez, Anne M.; Presting, Gernot G.

2011-01-01

342

Suppression of allergic and inflammatory responses by essential oils derived from herbal plants and citrus fruits.  

PubMed

The aim of the present study was to investigate the biological activity of 20 essential oils (EOs) derived from herbal plants and citrus fruits. The in vitro anti-allergic and anti-inflammatory activities of these oils were investigated, and the EO which was found to have the strongest activity of the 20 EOs examined, was investigated further to identify its components and bioactive compounds. The in vitro anti-allergic activity was determined by measuring the release of ?-hexosaminidase from rat basophilic leukemia (RBL-2H3) cells treated with the calcium ionophore, A23187. The in vitro anti-inflammatory activity was determined by measuring the production of tumor necrosis factor-? (TNF-?) in RAW264.7 murine macrophages treated with lipopolysaccharide. Among the EOs examined, lemongrass [Cymbopogon citratus (DC.) Stapf] elicited the strongest anti-allergic and anti-inflammatory effects. A principal component of this EO is citral (3,7-dimethyl-2,6-octadien-1-al) (74.5%), a mixture of the stereoisomers, geranial (trans-citral, 40.16%) and neral (cis-citral, 34.24%), as determined by chromatography-mass spectrometry analysis. The activities of citral and geranial are similar to those of lemongrass EO. These compounds elicited significant in vivo anti-allergic and anti-inflammatory effects, suppressing an immunoglobulin E (IgE)-induced passive cutaneous anaphylactic reaction in mice and a 12-O-tetradecanoylphorbol-13-acetate-induced inflammatory mouse ear edema, respectively. Our data demonstrate that lemongrass EO and its constituents, citral and geranial, may be a therapeutic candidate for allergic and inflammatory diseases. PMID:24682420

Mitoshi, Mai; Kuriyama, Isoko; Nakayama, Hiroto; Miyazato, Hironari; Sugimoto, Keiichiro; Kobayashi, Yuko; Jippo, Tomoko; Kuramochi, Kouji; Yoshida, Hiromi; Mizushina, Yoshiyuki

2014-06-01

343

Unraveling sterol-dependent membrane phenotypes by analysis of protein abundance-ratio distributions in different membrane fractions under biochemical and endogenous sterol depletion.  

PubMed

During the last decade, research on plasma membrane focused increasingly on the analysis of so-called microdomains. It has been shown that function of many membrane-associated proteins involved in signaling and transport depends on their conditional segregation within sterol-enriched membrane domains. High throughput proteomic analysis of sterol-protein interactions are often based on analyzing detergent resistant membrane fraction enriched in sterols and associated proteins, which also contain proteins from these microdomain structures. Most studies so far focused exclusively on the characterization of detergent resistant membrane protein composition and abundances. This approach has received some criticism because of its unspecificity and many co-purifying proteins. In this study, by a label-free quantitation approach, we extended the characterization of membrane microdomains by particularly studying distributions of each protein between detergent resistant membrane and detergent-soluble fractions (DSF). This approach allows a more stringent definition of dynamic processes between different membrane phases and provides a means of identification of co-purifying proteins. We developed a random sampling algorithm, called Unicorn, allowing for robust statistical testing of alterations in the protein distribution ratios of the two different fractions. Unicorn was validated on proteomic data from methyl-?-cyclodextrin treated plasma membranes and the sterol biosynthesis mutant smt1. Both, chemical treatment and sterol-biosynthesis mutation affected similar protein classes in their membrane phase distribution and particularly proteins with signaling and transport functions. PMID:24030099

Zauber, Henrik; Szymanski, Witold; Schulze, Waltraud X

2013-12-01

344

Effects of phytoestrogens and other plant-derived compounds on mesenchymal stem cells, bone maintenance and regeneration.  

PubMed

Phytoestrogens and other plant-derived compounds and extracts have been developed for the treatment of menopause-related complaints and disorders, e.g. hot flushes and osteoporosis. Since estrogens have been discussed to enhance the risk for hormone-sensitive cancers, research activities try to find alternatives. Phytoestrogens like genistein and resveratrol as well as other plant-derived compounds are capable of substituting for estrogens to some extent. Their effects on mesenchymal stem cells and the tissues derived therefrom have been investigated in vitro and in preclinical settings. Besides their well-known estrogenic, i.e. mainly antiresorptive effects on bone via estrogen receptor (ER) signalling, they also directly or indirectly affect osteogenic and adipogenic pathways. As a novel mechanism, phytoestrogens and plant-derived saponins and flavonoids like kaempferol and xanthohumol have been described to reciprocally affect the osteogenic versus the adipogenic differentiation pathway. Both, ER-mediated and other pathways mediate a shift towards osteogenesis by inhibiting PPAR? and C/EBP?, the key adipogenic transcription factors (TFs), while stimulating the key osteogenic TFs Runx2 and Sp7. Besides ER signalling, the broad spectrum of molecular mechanisms supporting osteogenesis comprises the modulation of PPAR?, Wnt/?-catenin, and Sirt1 signalling, which inversely influence the transcription or transactivation of osteogenic versus adipogenic TFs. Preventing the age- and hormone deficiency-related shift towards adipogenesis without provoking adverse estrogenic effects represents a very promising strategy for treating bone loss and other metabolic diseases beyond bone. Research on plant-derived compounds will have to be pursued in vitro as well as in preclinical studies and controlled clinical trials in humans are urgently needed. This article is part of a Special Issue entitled 'Phytoestrogens'. PMID:23262262

Schilling, Tatjana; Ebert, Regina; Raaijmakers, Nadja; Schütze, Norbert; Jakob, Franz

2014-01-01

345

CHROMOPHORIC DISSOLVED ORGANIC MATTER (CDOM) DERIVED FROM DECOMPOSITION OF VARIOUS VASCULAR PLANT AND ALGAL SOURCES  

EPA Science Inventory

Chromophoric dissolved organic (CDOM) in aquatic environments is derived from the microbial decomposition of terrestrial and microbial organic matter. Here we present results of studies of the spectral properties and photoreactivity of the CDOM derived from several organic matter...

346

Development of Fly Ash Derived Sorbents to Capture CO2 from Flue Gas of Power Plants  

SciTech Connect

This research program focused on the development of fly ash derived sorbents to capture CO{sub 2} from power plant flue gas emissions. The fly ash derived sorbents developed represent an affordable alternative to existing methods using specialized activated carbons and molecular sieves, that tend to be very expensive and hinder the viability of the CO{sub 2} sorption process due to economic constraints. Under Task 1 'Procurement and characterization of a suite of fly ashes', 10 fly ash samples, named FAS-1 to -10, were collected from different combustors with different feedstocks, including bituminous coal, PRB coal and biomass. These samples presented a wide range of LOI value from 0.66-84.0%, and different burn-off profiles. The samples also spanned a wide range of total specific surface area and pore volume. These variations reflect the difference in the feedstock, types of combustors, collection hopper, and the beneficiation technologies the different fly ashes underwent. Under Task 2 'Preparation of fly ash derived sorbents', the fly ash samples were activated by steam. Nitrogen adsorption isotherms were used to characterize the resultant activated samples. The cost-saving one-step activation process applied was successfully used to increase the surface area and pore volume of all the fly ash samples. The activated samples present very different surface areas and pore volumes due to the range in physical and chemical properties of their precursors. Furthermore, one activated fly ash sample, FAS-4, was loaded with amine-containing chemicals (MEA, DEA, AMP, and MDEA). The impregnation significantly decreased the surface area and pore volume of the parent activated fly ash sample. Under Task 3 'Capture of CO{sub 2} by fly ash derived sorbents', sample FAS-10 and its deashed counterpart before and after impregnation of chemical PEI were used for the CO{sub 2} adsorption at different temperatures. The sample FAS-10 exhibited a CO{sub 2} adsorption capacity of 17.5mg/g at 30 C, and decreases to 10.25mg/g at 75 C, while those for de-ashed counterpart are 43.5mg/g and 22.0 mg/g at 30 C and 75 C, respectively. After loading PEI, the CO{sub 2} adsorption capacity increased to 93.6 mg/g at 75 C for de-ashed sample and 62.1 mg/g at 75 C for raw fly ash sample. The activated fly ash, FAS-4, and its chemical loaded counterparts were tested for CO{sub 2} capture capacity. The activated carbon exhibited a CO{sub 2} adsorption capacity of 40.3mg/g at 30 C that decreased to 18.5mg/g at 70 C and 7.7mg/g at 120 C. The CO{sub 2} adsorption capacity profiles changed significantly after impregnation. For the MEA loaded sample the capacity increased to 68.6mg/g at 30 C. The loading of MDEA and DEA initially decreased the CO{sub 2} adsorption capacity at 30 C compared to the parent sample but increased to 40.6 and 37.1mg/g, respectively, when the temperature increased to 70 C. The loading of AMP decrease the CO{sub 2} adsorption capacity compared to the parent sample under all the studied temperatures. Under Task 4 'Comparison of the CO{sub 2} capture by fly ash derived sorbents with commercial sorbents', the CO{sub 2} adsorption capacities of selected activated fly ash carbons were compared to commercial activated carbons. The CO{sub 2} adsorption capacity of fly ash derived activated carbon, FAS-4, and its chemical loaded counterpart presented CO{sub 2} capture capacities close to 7 wt%, which are comparable to, and even better than, the published values of 3-4%.

M. Mercedes Maroto-Valer; John M. Andresen; Yinzhi Zhang; Zhe Lu

2003-12-31

347

Rapid analytical method for the determination of aflatoxins in plant-derived dietary supplement and cosmetic oils.  

PubMed

Consumption of edible oils derived from conventional crop plants is increasing because they are generally regarded as healthier alternatives to animal-based fats and oils. More recently, there has been increased interest in the use of alternative specialty plant-derived oils, including those from tree nuts (almonds, pistachios, and walnuts) and botanicals (borage, evening primrose, and perilla) both for direct human consumption (e.g., as salad dressings) and for the preparation of cosmetics, soaps, and fragrance oils. This has raised the issue as to whether or not exposure to aflatoxins can result from such oils. Although most crops are subject to analysis and control, it has generally been assumed that plant oils do not retain aflatoxins due to the high polarity and lipophobicity of these compounds. There is virtually no scientific evidence to support this supposition, and available information is conflicting. To improve the safety and consistency of botanicals and dietary supplements, research is needed to establish whether or not oils used directly, or in the formulation of products, contain aflatoxins. A validated analytical method for the analysis of aflatoxins in plant-derived oils is essential to establish the safety of dietary supplements for consumption or cosmetic use that contain such oils. The aim of this research was therefore to develop an HPLC method applicable to a wide variety of oils from different plant sources spiked with aflatoxins, thereby providing a basis for a comprehensive project to establish an intra- and interlaboratory validated analytical method for the analysis of aflatoxins in dietary supplements and cosmetics formulated with plant oils. PMID:20235534

Mahoney, Noreen; Molyneux, Russell J

2010-04-14

348

A Rapid Analytical Method for Determination of Aflatoxins in Plant-Derived Dietary Supplement and Cosmetic Oils  

PubMed Central

Consumption of edible oils derived from conventional crop plants is increasing because they are generally regarded as more healthy alternatives to animal based fats and oils. More recently there has been increased interest in the use of alternative specialty plant-derived oils, including those from tree nuts (almonds, pistachios and walnuts) and botanicals (borage, evening primrose and perilla) both for direct human consumption (e.g. as salad dressings) but also for preparation of cosmetics, soaps, and fragrance oils. This has raised the issue as to whether or not exposure to aflatoxins can result from such oils. Although most crops are subject to analysis and control, it has generally been assumed that plant oils do not retain aflatoxins due to their high polarity and lipophobicity of these compounds. There is virtually no scientific evidence to support this supposition and available information is conflicting. To improve the safety and consistency of botanicals and dietary supplements, research is needed to establish whether or not oils used directly, or in the formulation of products, contain aflatoxins. A validated analytical method for the analysis of aflatoxins in plant-derived oils is essential, in order to establish the safety of dietary supplements for consumption or cosmetic use that contain such oils. The aim of this research was therefore to develop an HPLC method applicable to a wide variety of oils from different plant sources spiked with aflatoxins, thereby providing a basis for a comprehensive project to establish an intra- and inter-laboratory validated analytical method for analysis of aflatoxins in dietary supplements and cosmetics formulated with plant oils. PMID:20235534

Mahoney, Noreen; Molyneux, Russell J.

2010-01-01

349

Traditional beverages derived from wild food plant species in the Vhembe District, Limpopo Province in South Africa.  

PubMed

Beverages derived from wild plant species play an important role in local and traditional food systems in rural communities such as in the Vhembe District, South Africa. Conducting research on such foodstuffs may help to prevent loss of indigenous knowledge on potential dietary sources for needy households. Through surveys and focussed group discussions, 41 different beverage-making plant species were identified. Traditional beverage making processes are of three types. Preparing teas involve a boiling process while juices are manually extracted following overnight soaking of the fruit pulp mixture. Brewing traditional beer usually requires a spontaneous fermentation process lasting 2-3 days. PMID:23621486

Rampedi, Isaac T; Olivier, Jana

2013-01-01

350

Utilization of plant-derived recombinant human ?-defensins (hBD-1 and hBD-2) for averting salmonellosis.  

PubMed

We describe the use of plant-made ?-defensins as effective antimicrobial substances for controlling salmonellosis, a deadly infection caused by Salmonella typhimurium (referred to further as S. typhi). Human ?-defensin-1 (hBD-1) and -2 (hBD-2) were expressed under the control of strong constitutive promoters in tobacco plants, and bio-active ?-defensins were successfully extracted. In the in vitro studies, enriched recombinant plant-derived human ?-defensin-1 (phBD-1) and -2 (phBD-2) obtained from both T1 and T2 transgenic plants showed significant antimicrobial activity against Escherichia coli and S. typhi when used individually and in various combinations. The 2:1 peptide combination of phBD-1:phBD-2 with peptides isolated from T1-and T2-generation plants reduced the growth of S. typhi by 96 and 85 %, respectively. In vivo studies employing the mouse model (Balb/c) of Salmonella infection clearly demonstrated that the administration of plant-derived defensins individually and in different combinations enhanced the mean survival time of Salmonella-infected animals. When treatment consisted of the 2:1 phBD-1:phBD-2 combination, approximately 50 % of the infected mice were still alive at 206 h post-inoculation; the lowest number of viable S. typhi was observed in the liver and spleen of infected animals. We conclude that plant-made recombinant ?-defensins (phBD-1 and phBD-2) are promising antimicrobial substances and have the potential to become additional tools against salmonellosis, particularly when used in combination. PMID:25417183

Patro, Sunita; Maiti, Soumitra; Panda, Santosh Kumar; Dey, Nrisingha

2015-04-01

351

The lipids of the common house cricket, Acheta domesticus L. III. Sterols  

Microsoft Academic Search

Sterols constitute 1.95% of the total extractable lipids ofAcheta domesticus L., of which 18% are esterified. The free sterols consist of cholestane-3?-ol (0.5%), ?5-cholestene-3?-ol (83.5%), ?7-cholestene-3?-ol (2.3%) ?5,7-cholestadiene-3?-ol (3%), ?5,22-cholestadiene-3?-ol (4%), ?5,7,22-cholestatriene-3?-ol (0.2%), campestane-3?-ol (0.03%), ?5-campestene-3?-ol (1.0%), ?7-campestene-3?-ol (trace), ?5,7-campestadiene-3?-ol (0.2%), stigmastane-3?-ol (0.09%), ?5-stigmastene-3?-ol (2.1%), ?7-stigmastene-3?-ol (0.04%), ?5,7-stigmastadiene-3?-ol (0.4%), ?5,22-stigmastadiene-3?ol (0.1%). The same sterols are present in the esterified sterol

Michael M. Martin; Glen A. Carls

1968-01-01

352

The mannoprotein TIR3 (CAGL0C03872g) is required for sterol uptake in Candida glabrata.  

PubMed

Sterol uptake in the pathogenic fungus, Candida glabrata, occurs via the sterol transporter, CgAus1p. Azole inhibition of sterol biosynthesis can under certain circumstances be reversed by adding exogenously sterol. Here we demonstrate that the CgTIR3 (CAGL0C03872g) gene product is also required for sterol uptake, since Cgtir3? strains fail to take up sterol both aerobically and under hypoxic conditions. Western analysis using an HA-tagged TIR3 strain showed that CgTir3p localizes to the cell wall, and its expression is induced by serum. Semi-quantitative reverse transcriptase-PCR also showed that two transcription regulatory genes, CgUPC2A and CgUPC2B, control CgTIR3 as well as CgAUS1 gene expression. Interestingly, complementation studies using Cgtir3? showed that ScDAN1, a mannoprotein required for sterol uptake in Saccharomyces cerevisiae, could not complement the C. glabrata TIR3 function. Furthermore, sterol analyses, in which both the CgAUS1 and CgTIR3 genes were constitutively expressed, resulted in aerobic sterol uptake although the amount of uptake was considerably less than that of cells cultured aerobically with serum. These results suggest that additional factors other than CgAUS1 and CgTIR3 are required for sterol uptake in C. glabrata. PMID:25463012

Inukai, Tatsuya; Nagi, Minoru; Morita, Akihiro; Tanabe, Koichi; Aoyama, Toshihiro; Miyazaki, Yoshitsugu; Bard, Martin; Nakayama, Hironobu

2015-02-01

353

Potential applications of plant based derivatives as fat replacers, antioxidants and antimicrobials in fresh and processed meat products.  

PubMed

Growing concern about diet and health has led to development of healthier food products. In general consumer perception towards the intake of meat and meat products is unhealthy because it may increase the risk of diseases like cardiovascular diseases, obesity and cancer, because of its high fat content (especially saturated fat) and added synthetic antioxidants and antimicrobials. Addition of plant derivatives having antioxidant components including vitamins A, C and E, minerals, polyphenols, flavanoids and terpenoids in meat products may decrease the risk of several degenerative diseases. To change consumer attitudes towards meat consumption, the meat industry is undergoing major transformations by addition of nonmeat ingredients as animal fat replacers, natural antioxidants and antimicrobials, preferably derived from plant sources. PMID:24845336

Hygreeva, Desugari; Pandey, M C; Radhakrishna, K

2014-09-01

354

Sterols and fecal indicator microorganisms in sediments from Admiralty Bay, Antarctica  

Microsoft Academic Search

A B S T R A C T Sediments from the proximity of Ferraz station outfall, located in Admiralty Bay, Antarctica, were analyzed for fecal indicator microorganisms and sterols during the austral summer of 1999\\/2000 in order to assess human sewage input. Concentrations of total sterols and coprostanol ranged from 0.09 to 19.6 µg.g -1 and < 0.01 and 14.0

César de Castro Martins; Rosalinda Carmela Montone; Rosa Carvalho Gamba; Vivian Helena Pellizari

2005-01-01

355

Sterols, methylsterols, and triterpene alcohols in three Theaceae and some other vegetable oils  

Microsoft Academic Search

The unsaponifiables from threeTheaceae (Camellia japonica L.,Camellia Sasanqua Thunb., andThea sinensis L.) oils and alfalfa, garden balsam, and spinach seed oils and shea fat were separated into four fractions: sterols, 4-methylsterols,\\u000a triterpene alcohols, and less polar compounds by thin layer chromatography. While the sterol fraction was the major one for\\u000a the unsaponifiables from alfalfa and spinach seed oils, the triterpene

Toshihiro Itoh; Toshitake Tamura; Taro Matsumoto

1974-01-01

356

Independent Regulation of Sterol Regulatory Element-Binding Proteins 1 and 2 in Hamster Liver  

Microsoft Academic Search

Two sterol regulatory element-binding proteins (SREBPs, designated SREBP-1 and SREBP-2), each ≈1150 amino acids in length, are attached to membranes of the endoplasmic reticulum and nuclear envelope in human and hamster tissue culture cells. In the absence of sterols, soluble fragments of ≈470 amino acids are released from both proteins by proteolytic cleavage. The soluble fragments enter the nucleus, where

Zeqi Sheng; Hideo Otani; Michael S. Brown; Joseph L. Goldstein

1995-01-01

357

An efficient diethyl ether-based soxhlet protocol to quantify faecal sterols from catchment waters  

Microsoft Academic Search

A study was conducted to evaluate the efficiency and reproducibility of a diethyl ether-based soxhlet extraction procedure for faecal sterols occurring from catchment waters. Water samples spiked with a mixture of faecal sterols were filtered and analytes were extracted using the diethyl ether-based soxhlet method and the Bligh and Dyer chloroform extraction process. For diethyl ether-based soxhlet extraction procedure, solvent

Vikas Kumar G. Shah; Hugh Dunstan; Warren Taylor

2006-01-01

358

Sterol Resistance in CHO Cells Traced to Point Mutation in SREBP Cleavage–Activating Protein  

Microsoft Academic Search

Through expression cloning we have isolated a cDNA-encoding SREBP cleavage–activating protein (SCAP), which regulates cholesterol metabolism by stimulating cleavage of transcription factors SREBP-1 and -2, thereby releasing them from membranes. The cDNA was isolated from Chinese hamster ovary cells with a dominant mutation that renders them resistant to sterol-mediated suppression of cholesterol synthesis and uptake. Sterol resistance was traced to

Xianxin Hua; Axel Nohturfft; Joseph L Goldstein; Michael S Brown

1996-01-01

359

Fluconazole Binding and Sterol Demethylation in Three CYP51 Isoforms Indicate Differences in Active Site Topology  

SciTech Connect

14{alpha}-Demethylase (CYP51) is a key enzyme in all sterol biosynthetic pathways (animals, fungi, plants, protists, and some bacteria), catalyzing the removal of the C-14 methyl group following cyclization of squalene. Based on mutations found in CYP51 genes from Candida albicans azole-resistant isolates obtained after fluconazole treatment of fungal infections, and using site-directed mutagenesis, we have found that fluconazole binding and substrate metabolism vary among three different CYP51 isoforms: human, fungal, and mycobacterial. In C. albicans, the Y132H mutant from isolates shows no effect on fluconazole binding, whereas the F145L mutant results in a 5-fold increase in its IC{sub 50} for fluconazole, suggesting that F145 (conserved only in fungal 14{alpha}-demethylases) interacts with this azole. In C. albicans, F145L accounts, in part, for the difference in fluconazole sensitivity reported between mammals and fungi, providing a basis for treatment of fungal infections. The C. albicans Y132H and human Y145H CYP51 mutants show essentially no effect on substrate metabolism, but the Mycobacterium tuberculosis F89H CYP51 mutant loses both its substrate binding and metabolism. Because these three residues align in the three isoforms, the results indicate that their active sites contain important structural differences, and further emphasize that fluconazole and substrate binding are uncoupled properties.

Bellamine, A.; Lepesheva, Galina I.; Waterman, Mike (Vanderbilt)

2010-11-16

360

Exploiting plant virus-derived components to achieve in planta expression and for templates for synthetic biology applications.  

PubMed

This review discusses the varying roles that have been played by many plant-viral regulatory sequences and proteins in the creation of plant-based expression systems and virus particles for use in nanotechnology. Essentially, there are two ways of expressing an exogenous protein: the creation of transgenic plants possessing a stably integrated gene construction, or the transient expression of the desired gene following the infiltration of the gene construct. Both depend on disarmed strains of Agrobacterium tumefaciens to deliver the created gene construction into cell nuclei, usually through the deployment of virus-derived components. The importance of efficient mRNA translation in the latter process is highlighted. Plant viruses replicate to sustain an infection to promote their survival. The major product of this, the virus particle, is finding increasing roles in the emerging field of bionanotechnology. One of the major products of plant-viral expression is the virus-like particle (VLP). These are increasingly playing a role in vaccine development. Similarly, many VLPs are suitable for the investigation of the many facets of the emerging field of synthetic biology, which encompasses the design and construction of new biological functions and systems not found in nature. Genetic and chemical modifications to plant-generated VLPs serve as ideal starter templates for many downstream synthetic biology applications. PMID:23452220

Saunders, Keith; Lomonossoff, George P

2013-10-01

361

Degradation and Preservation of Vascular Plant-derived Biomarkers in Grassland and Forest Soils from Western Canada  

Microsoft Academic Search

The total solvent extracts (TSE) of mineral and organic horizons of selected soils and overlying vegetation were analyzed using gas chromatography–mass spectrometry (GC–MS) to determine the composition of solvent-extractable (‘free’) lipids in soils and to study the degradation and possible preservation of vascular plant-derived molecular markers (biomarkers) in soils. Major compound classes in the TSE of soils and vegetation included

Angelika Otto; Myrna J. Simpson

2005-01-01

362

New meroterpenoids from the endophytic fungus Aspergillus flavipes AIL8 derived from the mangrove plant Acanthus ilicifolius.  

PubMed

Four new meroterpenoids (2-5), along with three known analogues (1, 6, and 7) were isolated from mangrove plant Acanthus ilicifolius derived endophytic fungus Aspergillus flavipes. The structures of these compounds were elucidated by NMR and MS analysis, the configurations were assigned by CD data, and the stereochemistry of 1 was confirmed by X-ray crystallography analysis. A possible biogenetic pathway of compounds 1-7 was also proposed. All compounds were evaluated for antibacterial and cytotoxic activities. PMID:25574738

Bai, Zhi-Qiang; Lin, Xiuping; Wang, Junfeng; Zhou, Xuefeng; Liu, Juan; Yang, Bin; Yang, Xianwen; Liao, Shengrong; Wang, Lishu; Liu, Yonghong

2015-01-01

363

New Meroterpenoids from the Endophytic Fungus Aspergillus flavipes AIL8 Derived from the Mangrove Plant Acanthus ilicifolius  

PubMed Central

Four new meroterpenoids (2–5), along with three known analogues (1, 6, and 7) were isolated from mangrove plant Acanthus ilicifolius derived endophytic fungus Aspergillus flavipes. The structures of these compounds were elucidated by NMR and MS analysis, the configurations were assigned by CD data, and the stereochemistry of 1 was confirmed by X-ray crystallography analysis. A possible biogenetic pathway of compounds 1–7 was also proposed. All compounds were evaluated for antibacterial and cytotoxic activities. PMID:25574738

Bai, Zhi-Qiang; Lin, Xiuping; Wang, Junfeng; Zhou, Xuefeng; Liu, Juan; Yang, Bin; Yang, Xianwen; Liao, Shengrong; Wang, Lishu; Liu, Yonghong

2015-01-01

364

Quantitation of fatty acids, sterols, and tocopherols in turpentine (Pistacia terebinthus Chia) growing wild in Turkey.  

PubMed

The chemical composition (fatty acids, tocopherols, and sterols) of the oil from 14 samples of turpentine (Pistacia terebinthus L.) fruits is presented in this study. The oil content of the samples varied in a relatively small range between 38.4 g/100 g and 45.1 g/100 g. The dominating fatty acid of the oil is oleic acid, which accounted for 43.0 to 51.3% of the total fatty acids. The total content of vitamin E active compounds in the oils ranged between 396.8 and 517.7 mg/kg. The predominant isomers were alpha- and gamma-tocopherol, with approximate equal amounts between about 110 and 150 mg/kg. The seed oil of P. terebinthus also contained different tocotrienols, with gamma-tocotrienol as the dominate compound of this group, which amounted to between 79 and 114 mg/kg. The total content of sterols of the oils was determined to be between 1341.3 and 1802.5 mg/kg, with beta-sitosterol as the predominent sterol that accounted for more than 80% of the total amount of sterols. Other sterols in noteworthy amounts were campesterol, Delta5-avenasterol, and stigmasterol, which came to about 3-5% of the total sterols. PMID:17002437

Matthäus, Bertrand; Ozcan, Mehmet Musa

2006-10-01

365

Natural products as potential human ether-a-go-go-related gene channel inhibitors - screening of plant-derived alkaloids.  

PubMed

Inhibition of the cardiac human ether-a-go-go-related gene channel is a problematic off-target pharmacological activity and, hence, a major safety liability in clinical practice. Several non-cardiac drugs have been restricted in their use, or even removed from the market due to this potentially fatal adverse effect. Comparatively little is known about the human ether-a-go-go-related gene inhibitory potential of plant-derived compounds. In the course of an ongoing human ether-a-go-go-related gene in vitro study, a total of 32 structurally diverse alkaloids of plant origin as well as two semi-synthetically obtained protoberberine derivatives were screened by means of an automated Xenopus oocyte assay. Protopine, (+)-bulbocapnine, (+)-N-methyllaurotetanine, (+)-boldine, (+)-chelidonine, (+)-corynoline, reserpine, and yohimbine reduced the human ether-a-go-go-related gene current by ? 50% at 100 µM, and were submitted to concentration-response experiments. Our data show that some widely occurring plant-derived alkaloids carry a potential risk for human ether-a-go-go-related gene toxicity. PMID:24963621

Schramm, Anja; Saxena, Priyanka; Chlebek, Jakub; Cahlíková, Lucie; Baburin, Igor; Hering, Steffen; Hamburger, Matthias

2014-06-01

366

RELATIVE RESISTANCE OF TOBACCO EXPRESSING TWO PLANT-DERIVED RESISTANCE MECHANISMS TO REPRESENTATIVE INSECTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Tobacco plants expressing an active form of maize ribosome inactivating protein and overexpressing tobacco anionic peroxidase in homozygous state were crossed, and hybrid plants expressing both proteins were examined for insect resistance relative to a wild-type cross. Significant feeding rate redu...

367

DEVELOPMENT OF PLANT-DERIVED SUBUNIT VACCINE CANDIDATE AGAINST NEWCASTLE DISEASE VIRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plant viruses do not replicate in animals, providing significant safety advantages over the use of animal virus-based vectors for vaccine delivery. Many plant viral coat proteins have the ability to assemble into virus-like particles (VLPs) which can be used as a scaffold to display heterologous pep...

368

The Biological Activity of ?-Mangostin, a Larvicidal Botanic Mosquito Sterol Carrier Protein-2 Inhibitor  

PubMed Central

?-Mangostin derived from mangosteen was identified as a mosquito sterol carrier protein-2 inhibitor via high throughput insecticide screening. ?-Mangostin was tested for its larvicidal activity against third instar larvae of six mosquito species, and the median lethal concentration values range from 0.84 to 2.90 ppm. The residual larvicidal activity of ?-mangostin was examined under semifield conditions. The results indicated that ?-mangostin was photolytic with a half-life of 53 min in water under full sunlight exposure. The effect of ?-mangostin on activities of major detoxification enzymes such as P450, glutathione S-transferase, and esterase was investigated. The results showed that ?-mangostin significantly elevated activities of P450 and glutathione S-transferase in larvae, whereas it suppressed esterase activity. Toxicity of ?-mangostin against young rats was studied, and there was no detectable adverse effect at dosages as high as 80 mg/kg. This is the first multifaceted study of the biological activity of ?-mangostin in mosquitoes. The results suggest that ?-mangostin may be a lead compound for the development of a new organically based mosquito larvicide. PMID:20380307

LARSON, RYAN T.; LORCH, JEFFREY M.; PRIDGEON, JULIA W.; BECNEL, JAMES J.; CLARK, GARY G.; LAN, QUE

2010-01-01

369

Plant regeneration and biochemical accumulation of hydroxybenzoic and hydroxycinnamic acid derivatives in Hypoxis hemerocallidea organ and callus cultures.  

PubMed

Micropropagation of Hypoxis hemerocallidea Fisch. and C.A. Mey was used as a model system to study the influence of cytokinins (CKs) on plant regeneration and biochemical accumulation of hydroxybenzoic and hydroxycinnamic acid derivatives in organ and callus cultures and their antioxidant activity. Fourteen free phenolic acids were detected using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) while antioxidant activity was evaluated using oxygen radical absorbance capacity (ORAC) and 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity. Cytokinins had a significant effect on the biochemical accumulation of hydroxybenzoic and hydroxycinnamic acid derivatives in H. hemerocallidea organ cultures. In particular, meta-topolin-treated organ cultures produced high concentrations of gallic, protocatechuic, gentisic, p-hydroxybenzoic, m-hydroxybenzoic, salicylic, chlorogenic and trans-cinnamic acids. The isoprenoid CK, N(6)-(2-isopentenyl)-adenine significantly increased the accumulation of hydroxycinnamic acid derivatives, namely, caffeic, p-coumaric, sinapic and ferulic acids. Cytokinin-treated organ cultures exhibited a significant increase in antioxidant activity, particularly in the ORAC model. In callus cultures, CKs decreased the concentrations of hydroxycinnamic acid derivatives and antioxidant activity when compared to the control. Overall, both CK type and concentration had a significant effect on plant regeneration, callus proliferation, biochemical accumulation of free phenolic acids and antioxidant activity of the resultant extracts. PMID:25219317

Moyo, Mack; Amoo, Stephen O; Aremu, Adeyemi O; Gruz, Ji?í; Subrtová, Michaela; Doležal, Karel; Van Staden, Johannes

2014-10-01

370

Changes in bile acids, FGF-19 and sterol absorption in response to bile salt hydrolase active L. reuteri NCIMB 30242.  

PubMed

The size and composition of the circulating bile acid (BA) pool are important factors in regulating the human gut microbiota. Disrupted regulation of BA metabolism is implicated in several chronic diseases. Bile salt hydrolase (BSH)-active Lactobacillus reuteri NCIMB 30242, previously shown to decrease LDL-cholesterol and increase circulating BA, was investigated for its dose response effect on BA profile in a pilot clinical study. Ten otherwise healthy hypercholesterolemic adults, recruited from a clinical trial site in London, ON, were randomized to consume delayed release or standard release capsules containing L. reuteri NCIMB 30242 in escalating dose over 4 weeks. In another aspect, 4 healthy normocholesterolemic subjects with LDL-C below 3.4 mmol/l received delayed release L. reuteri NCIMB 30242 at a constant dose over 4 weeks. The primary outcome measure was the change in plasma BA profile over the intervention period. Additional outcomes included circulating fibroblast growth factor (FGF)-19, plant sterols and LDL-cholesterol as well as fecal microbiota and bsh gene presence. After one week of intervention subjects receiving delayed release L. reuteri NCIMB 30242 increased total BA by 1.13 ± 0.67 ?mol/l (P = 0.02), conjugated BA by 0.67 ± 0.39 ?mol/l (P = 0.02) and unconjugated BA by 0.46 ± 0.43 ?mol/l (P = 0.07), which represented a greater than 2-fold change relative to baseline. Increases in BA were largely maintained post-week 1 and were generally correlated with FGF-19 and inversely correlated with plant sterols. This is the first clinical support showing that a BSH-active probiotic can significantly and rapidly influence BA metabolism and may prove useful in chronic diseases beyond hypercholesterolemia. PMID:25612224

Martoni, Christopher J; Labbé, Alain; Ganopolsky, Jorge G; Prakash, Satya; Jones, Mitchell L

2015-01-01

371

Generation and Analysis of Novel Plant-Derived Antibody-Based Therapeutic Molecules against West Nile Virus  

PubMed Central

Previously, our group engineered a plant-derived monoclonal antibody (MAb) (pHu-E16) that efficiently treated West Nile virus (WNV) infection in mice. In this study, we developed several pHu-E16 variants to improve its efficacy. These variants included a single-chain variable fragment (scFv) of pHu-E16 fused to the heavy chain (HC) constant domains (CH1-3) of human IgG (pHu-E16scFv-CH1-3) and a tetravalent molecule (Tetra pHu-E16) assembled from pHu-E16scFv-CH1-3 with a second pHu-E16scFv fused to the light chain (LC) constant region. pHu-E16scFv-CH1-3 and Tetra pHu-E16 were efficiently expressed and assembled in plants. To assess the impact of differences in N-linked glycosylation on pHu-E16 variant assembly and function, we expressed additional pHu-E16 variants with various combinations of HC and LC components. Our study revealed that proper pairing of HC and LC was essential for the complete N-glycan processing of antibodies in both plant and animal cells. Associated with their distinct N-glycoforms, pHu-E16, pHu-E16scFv-CH1-3 and Tetra pHu-E16 exhibited differential binding to C1q and specific Fc? receptors (Fc?R). Notably, none of the plant-derived Hu-E16 variants showed antibody-dependent enhancement (ADE) activity in CD32A+ human cells, suggesting the potential of plant-produced antibodies to minimize the adverse effect of ADE. Importantly, all plant-derived MAb variants exhibited at least equivalent in vitro neutralization and in vivo protection in mice compared to mammalian cell-produced Hu-E16. This study demonstrates the capacity of plants to express and assemble a large, complex and functional IgG-like tetravalent mAb variant and also provides insight into the relationship between MAb N-glycosylation, Fc?R and C1q binding, and ADE. These new insights may allow the development of safer and cost effective MAb-based therapeutics for flaviviruses, and possibly other pathogens. PMID:24675995

He, Junyun; Lai, Huafang; Engle, Michael; Gorlatov, Sergey; Gruber, Clemens; Steinkellner, Herta; Diamond, Michael S.; Chen, Qiang

2014-01-01

372

Synthesis of Plant Auxin Derivatives and Their Effects on Ceratopteris Richardii  

ERIC Educational Resources Information Center

Bioassays are commonly used to test the biological activity of chemicals and other exercises are presented in which students synthesize plant hormones. Lab exercise is conducted using commercially available auxins and auxin regulating compounds.

Stilts, Corey E.; Fisher, Roxanne

2007-01-01

373

Plant regeneration from carrot ( Daucus carota L.) anther culture derived embryos  

Microsoft Academic Search

The research concerned of the regeneration of plants from embryos obtained from anther cultures of seven carrot (Daucus carota L.) cultivars. The aim was to determine the influence of the regeneration medium on the efficiency of the regeneration process.\\u000a The optimization of the adaptation of the obtained plants was also carried out. Embryogenesis occurred on four of the tested\\u000a media:

K. Górecka; D. Krzy?anowska; W. Kiszczak; U. Kowalska

2009-01-01

374

Genetic fidelity of organized meristem-derived micropropagated plants: A critical reappraisal  

Microsoft Academic Search

Summary  The commercial multiplication of a large number of diverse plant species represents one of the major success stories of urilizing\\u000a tissue culture technology profitably. Micropropagation has now become a multibillion dollar industry, practised all over the\\u000a world. Of the various methods used to micropropagate plants, somatic embryogenesis and enhanced axillary branching have become\\u000a the principal methods of multiplication. Long-term benefits

Vijay Rani; S. N. Raina

2000-01-01

375

Characterization of plant-derived lactococci on the basis of their volatile compounds profile when grown in milk.  

PubMed

A total of twelve strains of lactococci were isolated from grass and vegetables (baby corn and fresh green peas). Ten of the isolates were classified as Lactococcus lactis subsp. lactis and two as Lactococcus lactis subsp. cremoris based on 16S rDNA sequencing. Most of the plant-derived strains were capable of metabolising a wide range of carbohydrates in that they fermented D-mannitol, amygdalin, potassium gluconate, l-arabinose, d-xylose, sucrose and gentibiose. None of the dairy control strains (i.e. L. lactis subsp. cremoris HP, L. lactis subsp. lactis IL1403 and Lactococcus lactis 303) were able to utilize any of these carbohydrates. The technological potential of the isolates as flavour-producing lactococci was evaluated by analysing their growth in milk and their ability to produce volatile compounds using solid phase micro-extraction of the headspace coupled to gas chromatography-mass spectrometry (SPME GC-MS). Principal component analysis (PCA) of the volatile compounds clearly separated the dairy strains from the plant derived strains, with higher levels of most flavour rich compounds. The flavour compounds produced by the plant isolates among others included; fatty acids such as 2- and 3-methylbutanoic acids, and hexanoic acid, several esters (e.g. butyl acetate and ethyl butanoate) and ketones (e.g. acetoin, diacetyl and 2-heptanone), all of which have been associated with desirable and more mature flavours in cheese. As such the production of a larger number of volatile compounds is a distinguishing feature of plant-derived lactococci and might be a desirable trait for the production of dairy products with enhanced flavour and/or aroma. PMID:24361833

Alemayehu, Debebe; Hannon, John A; McAuliffe, Olivia; Ross, R Paul

2014-02-17

376

Tropane and nicotine alkaloid biosynthesis-novel approaches towards biotechnological production of plant-derived pharmaceuticals.  

PubMed

Many plants belonging to the Solanaceae family have been used as a source of pharmaceuticals for centuries because of their active principles, tropane and nicotine alkaloids. Tropane alkaloids, atropine, hyoscyamine and scopolamine, are among the oldest drugs in medicine. On the other hand nicotine, the addictive agent in tobacco, has only recently gained attention as a backbone for novel potential alkaloids to be used for certain neurological diseases. The biotechnological production of alkaloids utilizing plant cells as hosts would be an attractive option. However, to date very little success in this field has been gained because of the lack of understanding how these compounds are synthesized in a plant cell. Metabolic engineering attempts have already shown that when the rate-limiting steps of the biosynthetic pathway are completely known and the respective genes cloned, the exact regulation towards desired medicinal products will be possible in the near future. The new functional genomics tools, which combine transcriptome and metabolome data, will create a platform to better understand a whole system and to engineer the complex plant biosynthetic pathways. With the help of this technology, it is not only possible to produce known plant metabolites more effectively but also to make arrays of new compounds in plants and cell cultures. PMID:17691989

Oksman-Caldentey, Kirsi-Marja

2007-08-01

377

Sterol/steroid metabolism and absorption in a generalist and specialist caterpillar: Effects of dietary sterol/steroid structure, mixture and ratio  

E-print Network

Sterol/steroid metabolism and absorption in a generalist and specialist caterpillar: Effects caterpillars were reared on two tobacco lines e one expressing a typical phystosterol profile, the other expressing high amounts/ratios of stanols and 3-ketosteroids. Caterpillars reared on the control tobacco

Behmer, Spencer T.

378

Plant-Derived Anti-Inflammatory Compounds: Hopes and Disappointments regarding the Translation of Preclinical Knowledge into Clinical Progress  

PubMed Central

Many diseases have been described to be associated with inflammatory processes. The currently available anti-inflammatory drug therapy is often not successful or causes intolerable side effects. Thus, new anti-inflammatory substances are still urgently needed. Plants were the first source of remedies in the history of mankind. Since their chemical characterization in the 19th century, herbal bioactive compounds have fueled drug development. Also, nowadays, new plant-derived agents continuously enrich our drug arsenal (e.g., vincristine, galantamine, and artemisinin). The number of new, pharmacologically active herbal ingredients, in particular that of anti-inflammatory compounds, rises continuously. The major obstacle in this field is the translation of preclinical knowledge into evidence-based clinical progress. Human trials of good quality are often missing or, when available, are frequently not suitable to really prove a therapeutical value. This minireview will summarize the current situation of 6 very prominent plant-derived anti-inflammatory compounds: curcumin, colchicine, resveratrol, capsaicin, epigallocatechin-3-gallate (EGCG), and quercetin. We will highlight their clinical potential and/or pinpoint an overestimation. Moreover, we will sum up the planned trials in order to provide insights into the inflammatory disorders that are hypothesized to be beneficially influenced by the compound. PMID:24987194

Fürst, Robert; Zündorf, Ilse

2014-01-01

379

Plant growth in Arabidopsis is assisted by compost soil-derived microbial communities  

PubMed Central

Plants in natural and agricultural environments are continuously exposed to a plethora of diverse microorganisms resulting in microbial colonization of roots and the rhizosphere. This process is believed to be accompanied by an intricate network of ongoing simultaneous interactions. In this study, we examined Arabidopsis thaliana roots and shoots in the presence or absence of whole microbial communities extracted from compost soil. The results show a clear growth promoting effect on Arabidopsis shoots in the presence of soil microbes compared to plants grown in microbe-free soil under otherwise identical conditions. Element analyses showed that iron uptake was facilitated by these mixed microbial communities which also led to transcriptional downregulation of genes required for iron transport. In addition, soil microbial communities suppressed the expression of marker genes involved in nitrogen uptake, oxidative stress/redox signaling, and salicylic acid (SA)-mediated plant defense while upregulating jasmonate (JA) signaling, cell wall organization/biosynthesis and photosynthesis. Multi-species analyses such as simultaneous transcriptional profiling of plants and their interacting microorganisms (metatranscriptomics) coupled to metagenomics may further increase our understanding of the intricate networks underlying plant-microbe interactions. PMID:23847639

Carvalhais, Lilia C.; Muzzi, Frederico; Tan, Chin-Hong; Hsien-Choo, Jin; Schenk, Peer M.

2013-01-01

380

Active root-inhabiting microbes identified by rapid incorporation of plant-derived carbon into RNA  

PubMed Central

Plant roots harbor a large diversity of microorganisms that have an essential role in ecosystem functioning. To better understand the level of intimacy of root-inhabiting microbes such as arbuscular mycorrhizal fungi and bacteria, we provided 13CO2 to plants at atmospheric concentration during a 5-h pulse. We expected microbes dependent on a carbon flux from their host plant to become rapidly labeled. We showed that a wide variety of microbes occurred in roots, mostly previously unknown. Strikingly, the greatest part of this unsuspected diversity corresponded to active primary consumers. We found 17 bacterial phylotypes co-occurring within roots of a single plant, including five potentially new phylotypes. Fourteen phylotypes were heavily labeled with the 13C. Eight were phylogenetically close to Burkholderiales, which encompass known symbionts; the others were potentially new bacterial root symbionts. By analyzing unlabeled and 13C-enriched RNAs, we demonstrated differential activity in C consumption among these root-inhabiting microbes. Arbuscular mycorrhizal fungal RNAs were heavily labeled, confirming the high carbon flux from the plant to the fungal compartment, but some of the fungi present appeared to be much more active than others. The results presented here reveal the possibility of uncharacterized root symbioses. PMID:17939995

Vandenkoornhuyse, Philippe; Mahé, Stéphane; Ineson, Philip; Staddon, Phil; Ostle, Nick; Cliquet, Jean-Bernard; Francez, André-Jean; Fitter, Alastair H.; Young, J. Peter W.

2007-01-01

381

Immunomodulatory activity of a plant extract containing human papillomavirus 16-E7 protein in human monocyte-derived dendritic cells.  

PubMed

This study reports the immunomodulatory activity on human monocyte derived dendritic cells (MDDCs) of a vaccine preparation shown to be effective against an HPV16-related tumour in an animal model. The vaccine is composed of extract from Nicotiana benthamiana leaves containing HPV16 E7 protein expressed by a potato virus X-derived vector (NbPVX-E7). The effect of the extract was evaluated on MDDC differentiation and maturation by monitoring the phenotypic expression of specific markers. The results show that NbPVX-E7 does not induce monocyte differentiation to dendritic cells, but does induce MDDC maturation. Plant extract does not influence MDDC-uptake of E7-FITC while it significantly improves the Ovalbumin-FITC uptake, considered as a model antigen. Importantly, NbPVX-E7-pulsed MDDCs/PBMCs are able to prime human blood-derived lymphocytes from healthy individuals to induce HPV16 E7-specific cytotoxic activity. This is a propaedeutic study for a possible use of E7-containing plant extract in human immunotherapy of HPV-related lesions. PMID:20074460

Di Bonito, P; Grasso, F; Mangino, G; Massa, S; Illiano, E; Franconi, R; Fanales-Belasio, E; Falchi, M; Affabris, E; Giorgi, C

2009-01-01

382

PPAR? as a Transcriptional Regulator for Detoxification of Plant Diet-Derived Unfavorable Compounds  

PubMed Central

Plants contain potentially toxic compounds for animals and animals have developed physiological strategies to detoxify the ingested toxins during evolution. Feeding mice with various plant seeds and grains showed unexpected result that only sesame killed PPAR?-null mice but not wild-type mice at all. A detailed analysis of this observation revealed that PPAR? is involved in the metabolism of toxic compounds from plants as well as endobiotic substrates by inducing phase I and phase II detoxification enzymes. PPAR? plays a vital role in direct or indirect activation of the relevant genes via the complex network among other xenobiotic nuclear receptors. Thus, PPAR? plays its wider and more extensive role in energy metabolism from natural food intake to fat storage than previously thought. PMID:22577367

Ashibe, Bunichiro; Nakajima, Yu; Fukui, Yuka; Motojima, Kiyoto

2012-01-01

383

Plant Sunscreens in Nature: UV and IR Spectroscopy of Sinapate Derivatives  

NASA Astrophysics Data System (ADS)

Plants are exposed to prolonged amounts of UV radiation, with elevated levels of UV-B (280-320 nm) as the ozone layer is depleted. When UV-B radiation penetrates the leaf epidermis, substantial oxidative damage can occur to plant tissues and plant growth can be inhibited. Sinapate esters, particularly sinapoyl malate, have been shown to efficiently prevent such damaging effects. By studying a series of molecules in this unique class under the isolated, cold conditions of a supersonic expansion, the fundamental UV-spectroscopic properties and photophysical aspects following UV absorption can be interrogated in detail. Sinapic acid and neutral sinapoyl malate were brought into the gas phase by laser desorption and detected via resonant two-photon ionization (R2PI). IR-UV double resonance methods were employed to obtain single-conformation UV and IR spectra. As the UV chromophore of interest is the sinapoyl moiety, sinapic acid served as the simplest model to compare directly to the more functionalized sinapoyl malate. It has a spectrum much like most aromatics, with a strong {??}^* origin, and well-resolved vibronic structure. By contrast, the spectrum for sinapoyl malate displays a large, broad absorption with little resolved vibronic structure, reflecting its role in nature as a pivotal and efficient UV protectant for plants, serving as the plant's sunscreen. Using conformer-specific IR spectroscopy, the individual conformations of both species were assigned and used as the basis for further ab initio calculations of the excited states that give rise to the observed behavior. Landry, L.G.; Chapple, C.S.; Last, R.L. Plant Physiol. {1995}, 109, 1159-1166.

Dean, Jacob C.; Walsh, Patrick S.; Zwier, Timothy S.; Allais, Florent

2013-06-01

384

TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5  

SciTech Connect

TERESA (Toxicological Evaluation of Realistic Emissions of Source Aerosols) involves exposing laboratory rats to realistic coal-fired power plant and mobile source emissions to help determine the relative toxicity of these PM sources. There are three coal-fired power plants in the TERESA program; this report describes the results of fieldwork conducted at the first plant, located in the Upper Midwest. The project was technically challenging by virtue of its novel design and requirement for the development of new techniques. By examining aged, atmospherically transformed aerosol derived from power plant stack emissions, we were able to evaluate the toxicity of PM derived from coal combustion in a manner that more accurately reflects the exposure of concern than existing methodologies. TERESA also involves assessment of actual plant emissions in a field setting--an important strength since it reduces the question of representativeness of emissions. A sampling system was developed and assembled to draw emissions from the stack; stack sampling conducted according to standard EPA protocol suggested that the sampled emissions are representative of those exiting the stack into the atmosphere. Two mobile laboratories were then outfitted for the study: (1) a chemical laboratory in which the atmospheric aging was conducted and which housed the bulk of the analytical equipment; and (2) a toxicological laboratory, which contained animal caging and the exposure apparatus. Animal exposures were carried out from May-November 2004 to a number of simulated atmospheric scenarios. Toxicological endpoints included (1) pulmonary function and breathing pattern; (2) bronchoalveolar lavage fluid cytological and biochemical analyses; (3) blood cytological analyses; (4) in vivo oxidative stress in heart and lung tissue; and (5) heart and lung histopathology. Results indicated no differences between exposed and control animals in any of the endpoints examined. Exposure concentrations for the scenarios utilizing secondary particles (oxidized emissions) ranged from 70-256 {micro}g/m{sup 3}, and some of the atmospheres contained high acidity levels (up to 49 {micro}g/m{sup 3} equivalent of sulfuric acid). However, caution must be used in generalizing these results to other power plants utilizing different coal types and with different plant configurations, as the emissions may vary based on these factors.

Annette Rohr

2006-03-01

385

The strigolactone germination stimulants of the plant-parasitic Striga and Orobanche spp. are derived from the carotenoid pathway.  

PubMed

The seeds of parasitic plants of the genera Striga and Orobanche will only germinate after induction by a chemical signal exuded from the roots of their host. Up to now, several of these germination stimulants have been isolated and identified in the root exudates of a series of host plants of both Orobanche and Striga spp. In most cases, the compounds were shown to be isoprenoid and belong to one chemical class, collectively called the strigolactones, and suggested by many authors to be sesquiterpene lactones. However, this classification was never proven; hence, the biosynthetic pathways of the germination stimulants are unknown. We have used carotenoid mutants of maize (Zea mays) and inhibitors of isoprenoid pathways on maize, cowpea (Vigna unguiculata), and sorghum (Sorghum bicolor) and assessed the effects on the root exudate-induced germination of Striga hermonthica and Orobanche crenata. Here, we show that for these three host and two parasitic plant species, the strigolactone germination stimulants are derived from the carotenoid pathway. Furthermore, we hypothesize how the germination stimulants are formed. We also discuss this finding as an explanation for some phenomena that have been observed for the host-parasitic plant interaction, such as the effect of mycorrhiza on S. hermonthica infestation. PMID:16183851

Matusova, Radoslava; Rani, Kumkum; Verstappen, Francel W A; Franssen, Maurice C R; Beale, Michael H; Bouwmeester, Harro J

2005-10-01

386

Immunogenicity of a plant-derived edible rotavirus subunit vaccine transformed over fifty generations  

Microsoft Academic Search

Major efforts have been put forth for the development of effective rotavirus vaccines including transgenic plant vaccines. Previous studies have reported that rotavirus VP7 maintains its neutralizing immunity when it is transformed into the potato genome. The present study was aimed at investigating the hereditary stability of VP7-transformed potatoes over fifty generations. The VP7 gene was stably transcribed and expressed

Jin-Tao Li; Lei Fei; Zhi-Rong Mou; Jing Wei; Yan Tang; Hai-Yang He; Li Wang; Yu-Zhang Wu

2006-01-01

387

BIOPHYSICAL PROPERTIES OF CAY-1, A FUNGICIDAL PLANT-DERIVED SAPONIN  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background: CAY-1, a plant saponin, is lethal to several medically and agriculturally important fungi. CAY-1 displays synergy with amphotericin B and itraconzaole against fungi. To further elucidate its properties, we studied pH effect on CAY-1 activity and possible fungal wall and membrane binding ...

388

The influence of humic acids derived from earthworm-processed organic wastes on plant growth  

Microsoft Academic Search

Some effects of humic acids, formed during the breakdown of organic wastes by earthworms (vermicomposting), on plant growth were evaluated. In the first experiment, humic acids were extracted from pig manure vermicompost using the classic alkali\\/acid fractionation procedure and mixed with a soilless container medium (Metro-Mix 360), to provide a range of 0, 50, 100, 150, 200, 250, 500, 1000,

R. M. Atiyeh; S. Lee; C. A. Edwards; N. Q. Arancon; J. D. Metzger

2002-01-01

389

Plant-derived phenolic compounds impair the remediation of acid mine drainage using treatment wetlands  

Microsoft Academic Search

The use of wetlands to remediate acid mine drainage has expanded rapidly since the realisation that acid coal mine drainage running into natural sphagnum wetlands undergoes an increase in pH and a precipitation of metals. However, our study suggests that the inclusion of plants in the acid mine drainage treatment system may be questionable, due to inefficiencies caused by exudation

Rachel A. White; Chris Freeman; Hojeong Kang

2011-01-01

390

Screening of anti- Helicobacter pylori herbs deriving from Taiwanese folk medicinal plants  

Microsoft Academic Search

In this study, extracts from 50 Taiwanese folk medicinal plants were examined and screened for anti-Helicobacter pylori activity. Ninety-five percent ethanol was used for herbal extraction. Paederia scandens (Lour.) Merr. (PSM), Plumbago zeylanica L. (PZL), Anisomeles indica (L.) O. Kuntze (AIOK), Bombax malabaricum DC. (BMDC) and Alpinia speciosa (J. C. Wendl.) K. Schum. (ASKS) and Bombax malabaricum DC. (BMDC) all

Yuan-Chuen Wang; Tung-Liang Huang

2005-01-01

391

Using vegetative index and modified derivative for early detection of soybean plant injury from glyphosate  

Technology Transfer Automated Retrieval System (TEKTRAN)

Glyphosate is a non-selective, systemic herbicide highly toxic to sensitive plant species, and its use has seen a significant increase due to the increased adoption of genetically modified glyphosate-resistant crops since the mid-1990s. Glyphosate application for weed control in glyphosate-resistant...

392

TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5  

SciTech Connect

Determining the health impacts of different sources and components of fine particulate matter (PM2.5) is an important scientific goal, because PM is a complex mixture of both inorganic and organic constituents that likely differ in their potential to cause adverse health outcomes. The TERESA (Toxicological Evaluation of Realistic Emissions of Source Aerosols) study focused on two PM sources - coal-fired power plants and mobile sources - and sought to investigate the toxicological effects of exposure to realistic emissions from these sources. The DOE-EPRI Cooperative Agreement covered the performance and analysis of field experiments at three power plants. The mobile source component consisted of experiments conducted at a traffic tunnel in Boston; these activities were funded through the Harvard-EPA Particulate Matter Research Center and will be reported separately in the peer-reviewed literature. TERESA attempted to delineate health effects of primary particles, secondary (aged) particles, and mixtures of these with common atmospheric constituents. The study involved withdrawal of emissions directly from power plant stacks, followed by aging and atmospheric transformation of emissions in a mobile laboratory in a manner that simulated downwind power plant plume processing. Secondary organic aerosol (SOA) derived from the biogenic volatile organic compound {alpha}-pinene was added in some experiments, and in others ammonia was added to neutralize strong acidity. Specifically, four scenarios were studied at each plant: primary particles (P); secondary (oxidized) particles (PO); oxidized particles + secondary organic aerosol (SOA) (POS); and oxidized and neutralized particles + SOA (PONS). Extensive exposure characterization was carried out, including gas-phase and particulate species. Male Sprague Dawley rats were exposed for 6 hours to filtered air or different atmospheric mixtures. Toxicological endpoints included (1) breathing pattern; (2) bronchoalveolar lavage (BAL) fluid cytology and biochemistry; (3) blood cytology; (4) in vivo oxidative stress in heart and lung tissue; and (5) heart and lung histopathology. In addition, at one plant, cardiac arrhythmias and heart rate variability (HRV) were evaluated in a rat model of myocardial infarction. Statistical analyses included analyses of variance (ANOVA) to determine differences between exposed and control animals in response to different scenario/plant combinations; univariate analyses to link individual scenario components to responses; and multivariate analyses (Random Forest analyses) to evaluate component effects in a multipollutant setting. Results from the power plant studies indicated some biological responses to some plant/scenario combinations. A number of significant breathing pattern changes were observed; however, significant clinical changes such as specific irritant effects were not readily apparent, and effects tended to be isolated changes in certain respiratory parameters. Some individual exposure scenario components appeared to be more strongly and consistently related to respiratory parameter changes; however, the specific scenario investigated remained a better predictor of response than individual components of that scenario. Bronchoalveolar lavage indicated some changes in cellularity of BAL fluid in response to the POS and PONS scenarios; these responses were considered toxicologically mild in magnitude. No changes in blood cytology were observed at any plant or scenario. Lung oxidative stress was increased with the POS scenario at one plant, and cardiac oxidative stress was increased with the PONS scenario also at one plant, suggesting limited oxidative stress in response to power plant emissions with added atmospheric constituents. There were some mild histological findings in lung tissue in response to the P and PONS scenarios. Finally, the MI model experiments indicated that premature ventricular beat frequency was increased at the plant studied, while no changes in heart rate, HRV, or electrocardiographic intervals were observed. Overall, the

Annette C. Rohr; Petros Koutrakis; John Godleski

2011-03-31

393

Evidence for lateral gene transfer (LGT) in the evolution of eubacteria-derived small GTPases in plant organelles  

PubMed Central

The genomes of free-living bacteria frequently exchange genes via lateral gene transfer (LGT), which has played a major role in bacterial evolution. LGT also played a significant role in the acquisition of genes from non-cyanobacterial bacteria to the lineage of “primary” algae and land plants. Small GTPases are widely distributed among prokaryotes and eukaryotes. In this study, we inferred the evolutionary history of organelle-targeted small GTPases in plants. Arabidopsis thaliana contains at least one ortholog in seven subfamilies of OBG-HflX-like and TrmE-Era-EngA-YihA-Septin-like GTPase superfamilies (together referred to as Era-like GTPases). Subcellular localization analysis of all Era-like GTPases in Arabidopsis revealed that all 30 eubacteria-related GTPases are localized to chloroplasts and/or mitochondria, whereas archaea-related DRG and NOG1 are localized to the cytoplasm and nucleus, respectively, suggesting that chloroplast- and mitochondrion-localized GTPases are derived from the ancestral cyanobacterium and ?-proteobacterium, respectively, through endosymbiotic gene transfer (EGT). However, phylogenetic analyses revealed that plant organelle GTPase evolution is rather complex. Among the eubacterium-related GTPases, only four localized to chloroplasts (including one dual targeting GTPase) and two localized to mitochondria were derived from cyanobacteria and ?-proteobacteria, respectively. Three other chloroplast-targeted GTPases were related to ?-proteobacterial proteins, rather than to cyanobacterial GTPases. Furthermore, we found that four other GTPases showed neither cyanobacterial nor ?-proteobacterial affiliation. Instead, these GTPases were closely related to clades from other eubacteria, such as Bacteroides (Era1, EngB-1, and EngB-2) and green non-sulfur bacteria (HflX). This study thus provides novel evidence that LGT significantly contributed to the evolution of organelle-targeted Era-like GTPases in plants. PMID:25566271

Suwastika, I. Nengah; Denawa, Masatsugu; Yomogihara, Saki; Im, Chak Han; Bang, Woo Young; Ohniwa, Ryosuke L.; Bahk, Jeong Dong; Takeyasu, Kunio; Shiina, Takashi

2014-01-01

394

Field determination of optimal dates for the discrimination of invasive wetland plant species using derivative spectral analysis  

USGS Publications Warehouse

Mapping invasive plant species in aquatic and terrestrial ecosystems helps to understand the causes of their progression, manage some of their negative consequences, and control them. In recent years, a variety of new remote-sensing techniques, like Derivative Spectral Analysis (DSA) of hyperspectral data, have been developed to facilitate this mapping. A number of questions related to these techniques remain to be addressed. This article attempts to answer one of these questions: Is the application of DSA optimal at certain times of the year? Field radiometric data gathered weekly during the summer of 1999 at selected field sites in upstate New York, populated with purple loosestrife (Lythrum salicaria L.), common reed (Phragmites australis (Cav.)) and cattail (Typha L.) are analyzed using DSA to differentiate among plant community types. First, second and higher-order derivatives of the reflectance spectra of nine field plots, varying in plant composition, are calculated and analyzed in detail to identify spectral ranges in which one or more community types have distinguishing features. On the basis of the occurrence and extent of these spectral ranges, experimental observations suggest that a satisfactory differentiation among community types was feasible on 30 August, when plants experienced characteristic phenological changes (transition from flowers to seed heads). Generally, dates in August appear optimal from the point of view of species differentiability and could be selected for image acquisitions. This observation, as well as the methodology adopted in this article, should provide a firm basis for the acquisition of hyperspectral imagery and for mapping the targeted species over a broad range of spatial scales. ?? 2005 American Society for Photogrammetry and Remote Sensing.

Laba, M.; Tsai, F.; Ogurcak, D.; Smith, S.; Richmond, M.E.

2005-01-01

395

High frequency plant regeneration from zygotic-embryo-derived embryogenic cell suspension cultures of watershield ( Brasenia schreberi )  

Microsoft Academic Search

An improved protocol for high frequency plant regeneration via somatic embryogenesis from zygotic embryo-derived cell suspension\\u000a cultures of watershield (Brasenia schreberi) was developed. Zygotic embryos formed pale-yellow globular structures and white friable callus at a frequency of 80% when\\u000a cultured on half-strength MS medium supplemented with 0.3 mg l?1 2,4-D. However, the frequency of formation of pale-yellow globular structures and white friable

Myung Jin Oh; Hye Ryun Na; Hong-Keun Choi; Jang Ryol Liu; Suk Weon Kim

2008-01-01

396

Structure-Activity Relationship Study of the Plant-Derived Decapeptide OSIP108 Inhibiting Candida albicans Biofilm Formation  

PubMed Central

We performed a structure-activity relationship study of the antibiofilm plant-derived decapeptide OSIP108. Introduction of positively charged amino acids R, H, and K resulted in an up-to-5-fold-increased antibiofilm activity against Candida albicans compared to native OSIP108, whereas replacement of R9 resulted in complete abolishment of its antibiofilm activity. By combining the most promising amino acid substitutions, we found that the double-substituted OSIP108 analogue Q6R/G7K had an 8-fold-increased antibiofilm activity. PMID:24913176

Delattin, Nicolas; De Brucker, Katrijn; Craik, David J.; Cheneval, Olivier; De Coninck, Barbara; Thevissen, Karin

2014-01-01

397

Comparison and analysis of fatty acids, sterols, and tocopherols in eight vegetable oils.  

PubMed

The similarities and differences of eight vegetable oils produced in China were investigated in terms of their fatty acid, sterol, and tocopherol compositions and subsequent data processing by hierarchical clustering analysis and principal component analysis. The lipid profiles, acquired by analytical techniques tailored to each lipid class, revealed great similarities among the fatty acid profiles of corn and sesame oil as well as few differences in their sterol profiles. It turns out that not only was there great similarity between the fatty acid profiles of corn oil and sesame oil but also there were not too many differences for the sterol profiles. Sunflower and tea-seed oil showed similar sterol compositions, while the tea-seed oil tocopherol was very similar to palm oil. The results demonstrated that the use of only one of these profiles was unreliable for indentifying oil origin and authenticity. In contrast, the use of the sterol or tocopherol profile together with the fatty acid profile more accurately discriminates these oils. PMID:22054411

Li, Changmo; Yao, Yunping; Zhao, Guozhong; Cheng, Wen; Liu, Huilin; Liu, Chunyang; Shi, Zhen; Chen, Yao; Wang, Shuo

2011-12-14

398

LXR signaling couples sterol metabolism to proliferation in the acquired immune response  

PubMed Central

Summary We demonstrate here that LXR–dependent sterol homeostasis is a physiologically-regulated determinant of cell proliferation and acquired immune responses. T cell activation triggers simultaneous suppression of the LXR pathway for cholesterol transport and induction of the SREBP pathway for cholesterol synthesis. This coordinated program is engaged in part through induction of the sterol-metabolizing enzyme SULT2B1, expression of which in T cells blocks LXR signaling. Forced induction of LXR target genes during T cell activation markedly inhibits mitogen-driven expansion, whereas loss of LXR? confers a proliferative advantage. Inactivation of the sterol transporter ABCG1 in T cells uncouples LXR signaling from proliferation, directly linking sterol homeostasis to the anti-proliferative action of LXR. Mice lacking LXR? exhibit lymphoid hyperplasia and enhanced responses to antigenic challenge, indicating that proper regulation of LXR-dependent sterol metabolism is important for immune responses. These data implicate LXR signaling in a metabolic checkpoint that modulates cell proliferation and immunity. PMID:18614014

Bensinger, Steven J.; Bradley, Michelle N.; Joseph, Sean B.; Zelcer, Noam; Janssen, Edith M.; Hausner, Mary Ann; Shih, Roger; Parks, John S.; Edwards, Peter A.; Jamieson, Beth D.; Tontonoz, Peter

2009-01-01

399

A Novel Sterol Desaturase-Like Protein Promoting Dealkylation of Phytosterols in Tetrahymena thermophila?  

PubMed Central

The gene TTHERM_00438800 (DES24) from the ciliate Tetrahymena thermophila encodes a protein with three conserved histidine clusters, typical of the fatty acid hydroxylase superfamily. Despite its high similarity to sterol desaturase-like enzymes, the phylogenetic analysis groups Des24p in a separate cluster more related to bacterial than to eukaryotic proteins, suggesting a possible horizontal gene transfer event. A somatic knockout of DES24 revealed that the gene encodes a protein, Des24p, which is involved in the dealkylation of phytosterols. Knocked-out mutants were unable to eliminate the C-24 ethyl group from C29 sterols, whereas the ability to introduce other modifications, such as desaturations at positions C-5(6), C-7(8), and C-22(23), were not altered. Although C-24 dealkylations have been described in other organisms, such as insects, neither the enzymes nor the corresponding genes have been identified to date. Therefore, this is the first identification of a gene involved in sterol dealkylation. Moreover, the knockout mutant and wild-type strain differed significantly in growth and morphology only when cultivated with C29 sterols; under this culture condition, a change from the typical pear-like shape to a round shape and an alteration in the regulation of tetrahymanol biosynthesis were observed. Sterol analysis upon culture with various substrates and inhibitors indicate that the removal of the C-24 ethyl group in Tetrahymena may proceed by a mechanism different from the one currently known. PMID:21257793

Tomazic, Mariela L.; Najle, Sebastián R.; Nusblat, Alejandro D.; Uttaro, Antonio D.; Nudel, Clara B.

2011-01-01

400

Stimulation of hepatic biogenesis of sterols on administration of adenosine compounds.  

PubMed Central

1. Re-feeding starved rats increased the biogenesis of sterols in livers, with highest activity at 6h after the start of food intake. 2. Complete deficiency of protein or fat and partial deficiency of carbohydrate in the diet had no effect on sterol biogenesis. 3. Glucose, citrate or pyruvate, when administered intraperitoneally to starved rats, stimulated the biogenesis of sterols only at high concentrations. 4. ATP given intraperitoneally at low concentrations (10mg/rat) stimulated biogenesis of sterols, but not of fatty acids, from [1-14C]acetate. This effect was also obtained with other adenosine compounds, but not with adenine or guanosine. 5. Administration of adenosine compounds to starved rats also increased the incorporation of [1-14C]acetate into sterols in liver slices and also the activity of microsomal 3-hydroxy-3-methylglutaryl-CoA reductase. The results suggest a regulatory role for adenosine compounds in the hepatic biogenesis of isoprenoid compounds. PMID:942390

Rao, G S; George, R; Ramasarma, T

1976-01-01

401

Characterization of the Saccharomyces cerevisiae ERG27 gene encoding the 3-keto reductase involved in C-4 sterol demethylation  

PubMed Central

The last unidentified gene encoding an enzyme involved in ergosterol biosynthesis in Saccharomyces cerevisiae has been cloned. This gene, designated ERG27, encodes the 3-keto sterol reductase, which, in concert with the C-4 sterol methyloxidase (ERG25) and the C-3 sterol dehydrogenase (ERG26), catalyzes the sequential removal of the two methyl groups at the sterol C-4 position. We developed a strategy to isolate a mutant deficient in converting 3-keto to 3-hydroxy-sterols. An ergosterol auxotroph unable to synthesize sterol or grow without sterol supplementation was mutagenized. Colonies were then selected that were nystatin-resistant in the presence of 3-ketoergostadiene and cholesterol. A new ergosterol auxotroph unable to grow on 3-ketosterols without the addition of cholesterol was isolated. The gene (YLR100w) was identified by complementation. Segregants containing the YLR100w disruption failed to grow on various types of 3-keto sterol substrates. Surprisingly, when erg27 was grown on cholesterol- or ergosterol-supplemented media, the endogenous compounds that accumulated were noncyclic sterol intermediates (squalene, squalene epoxide, and squalene dioxide), and there was little or no accumulation of lanosterol or 3-ketosterols. Feeding experiments in which erg27 strains were supplemented with lanosterol (an upstream intermediate of the C-4 demethylation process) and cholesterol (an end-product sterol) demonstrated accumulation of four types of 3-keto sterols identified by GC/MS and chromatographic properties: 4-methyl-zymosterone, zymosterone, 4-methyl-fecosterone, and ergosta-7,24 (28)-dien-3-one. In addition, a fifth intermediate was isolated and identified by 1H NMR as a 4-methyl-24,25-epoxy-cholesta-7-en-3-one. Implications of these results are discussed. PMID:10535978

Gachotte, D.; Sen, S. E.; Eckstein, J.; Barbuch, R.; Krieger, M.; Ray, B. D.; Bard, M.

1999-01-01

402

System of handling refuse derived fuel utilizing same to fire power plants  

Microsoft Academic Search

This patent describes an apparatus for supplying refuse derived fuel, that has been shredded to a predetermined nominal size to a furnace fuel supply chute that is open to the furnace fire chamber, in a continuous and uninterrupted flow, for heating the furnace boiler. The apparatus consists of: a large primary surge capacity bin. The bin includes an upper intake

Dumbaugh

1988-01-01

403

Plant-derived triterpenoids and analogues as antitumor and anti-HIV agents†  

PubMed Central

This article reviews the antitumor and anti-HIV activities of naturally occurring triterpenoids, including the lupane, ursane, oleanane, lanostane, dammarane, and miscellaneous scaffolds. Structure–activity relationships of selected natural compounds and their synthetic derivatives are also discussed. PMID:19779642

Kuo, Reen-Yen; Qian, Keduo; Morris-Natschke, Susan L.; Lee, Kuo-Hsiung

2013-01-01

404

Characterization of Plant-derived Dissolved Organic Matter by Multiple Spectroscopic Techniques  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dissolved organic matter (DOM) derived from fresh or early-stage decomposing soil amendment materials may play an important role in the process of organic matter accumulation. In this study, eight DOM samples from alfalfa, corn, crimson clover, hairy vetch, lupin, soybean, wheat and dairy manure wer...

405

Observing plants dealing with soil water stress: Daily soil moisture fluctuations derived from polymer tensiometers  

NASA Astrophysics Data System (ADS)

Periods of soil water deficit often occur within a plant's life cycle, even in temperate deciduous and rain forests (Wilson et al. 2001, Grace 1999). Various experiments have shown that roots are able to sense the distribution of water in the soil, and produce signals that trigger changes in leaf expansion rate and stomatal conductance (Blackman and Davies 1985, Gollan et al. 1986, Gowing et al. 1990 Davies and Zhang 1991, Mansfield and De Silva 1994, Sadras and Milroy 1996). Partitioning of water and air in the soil, solute distribution in soil water, water flow through the soil, and water availability for plants can be determined according to the distribution of the soil water potential (e.g. Schröder et al. 2013, Kool et al. 2014). Understanding plant water uptake under dry conditions has been compromised by hydrological instrumentation with low accuracy in dry soils due to signal attenuation, or a compromised measurement range (Whalley et al. 2013). Development of polymer tensiometers makes it possible to study the soil water potential over a range meaningful for studying plant responses to water stress (Bakker et al. 2007, Van der Ploeg et al. 2008, 2010). Polymer tensiometer data obtained from a lysimeter experiment (Van der Ploeg et al. 2008) were used to analyse day-night fluctuations of soil moisture in the vicinity of maize roots. To do so, three polymer tensiometers placed in the middle of the lysimeter from a control, dry and very dry treatment (one lysimeter per treatment) were used to calculate water content changes over 12 hours. These 12 hours corresponded with the operation of the growing light. Soil water potential measurements in the hour before the growing light was turned on or off were averaged. The averaged value was used as input for the van Genuchten (1980) model. Parameters for the model were obtained from laboratory determination of water retention, with a separate model parameterization for each lysimeter setup. Results show daily fluctuations in water content changes, with both root water uptake and root water excretion. The magnitude of the water content change was in the same order for all treatments, thus suggesting compensatory uptake. References Bakker G, Van der Ploeg MJ, de Rooij GH, Hoogendam CW, Gooren HPA, Huiskes C, Koopal LK and Kruidhof H. New polymer tensiometers: Measuring matric pressures down to the wilting point. Vadose Zone J. 6: 196-202, 2007. Blackman PG and Davies WJ. Root to shoot communication in maize plants of the effects of soil drying. J. Exp. Bot. 36: 39-48, 1985. Davies WJ and Zhang J. Root signals and the regulation of growth and development of plants in drying soil. Annu. Rev. Plant Physiol. Plant Mol. Biol. 42: 55-76, 1991. Gollan T, Passioura JB and Munns R. Soil water status affects the stomatal conductance of fully turgid wheat and sunflower leafs. Aust. J. Plant Physiol. 13: 459-464, 1986. Gowing DJG, Davies WJ and Jones HG. A Positive Root-sourced Signal as an Indicator of Soil Drying in Apple, Malus x domestica Borkh. J. Exp. Bot. 41: 1535-1540, 1990. Grace J. Environmental controls of gas exchange in tropical rain forests. In: Press, M.C, J.D. Scholes and M.G. Barker (ed.). Physiological plant ecology: the 39th Symposium of the British Ecological Society. Blackwell Science, United Kingdom, 1999. Kool D, Agam N, Lazarovitch N, Heitman JL, Sauer TJ, Ben-Gal A. A review of approaches for evapotranspiration partitioning. Agricultural and Forest Meteorology 184: 56- 70, 2014. Mansfield TA and De Silva DLR. Sensory systems in the roots of plants and their role in controlling stomatal function in the leaves. Physiol. Chem. Phys. & Med. 26: 89-99, 1994. Sadras VO and Milroy SP. Soil-water thresholds for the responses of leaf expansion and gas exchange: a review. Field Crops Res. 47: 253-266, 1996. Schröder N, Lazarovitch N, Vanderborcht J, Vereecken H, Javaux M. Linking transpiration reduction to rhizosphere salinity using a 3D coupled soil-plant model. Plant Soil 2013, doi: 10.1007/s11104-013-1990-8 Van der Ploeg MJ, Gooren HPA, Bakker G and de Rooij GH.

van der Ploeg, Martine; de Rooij, Gerrit

2014-05-01

406

Evaluation of the Leishmanicidal and Cytotoxic Potential of Essential Oils Derived From Ten Colombian Plants  

PubMed Central

Background The leishmanicidal and cytotoxic activity of ten essential oils obtained from ten plant specimens were evaluated. Methods Essential oils were obtained by the steam distillation of plant leaves without any prior processing. Cytotoxicity was tested on J774 macrophages and leishmanicidal activity was assessed against four species of Leishmania associated with cutaneous leishmaniasis. Results Seven essential oils exhibited activity against Leishmania parasites, five of which were toxic against J774 macrophages. Selectivity indices of >6 and 13 were calculated for the essential oils of Ocimum basilicum and Origanum vulgare, respectively. Conclusion The essential oil of Ocimum basilicum was active against promastigotes of Leishmania and innocuous to J774 macrophages at concentrations up to 1600 µg/mL and should be further investigated for leishmanicidal activity in others in vitro and in vivo experimental models. PMID:23682270

Sanchez-Suarez, JF; Riveros, I; Delgado, G

2013-01-01

407

Liquiritigenin is a plant-derived highly selective estrogen receptor ? agonist  

PubMed Central

After the Women’s Health Initiative found that the risks of hormone therapy outweighed the benefits, a need for alternative drugs to treat menopausal symptoms has emerged. We explored the possibility that botanical agents used in Traditional Chinese Medicine for menopausal symptoms contain ER?-selective estrogens. We previously reported that an extract containing 22 herbs, MF101 has ER?-selective properties. In this study we isolated liquiritigenin, the most active estrogenic compound from the root of Glycyrrhizae uralensis Fisch, which is one of the plants found in MF101. Liquiritigenin activated multiple ER regulatory elements and native target genes with ER? but not ER?. The ER?-selectivity of liquiritigenin was due to the selective recruitment of the coactivator steroid receptor coactivator-2 to target genes. In a mouse xenograph model, liquiritigenin did not stimulate uterine size or tumorigenesis of MCF-7 breast cancer cells. Our results demonstrate that some plants contain highly selective estrogens for ER?. PMID:18177995

Mersereau, Jennifer E.; Levy, Nitzan; Staub, Richard E.; Baggett, Scott; Zogric, Tetyana; Chow, Sylvia; Ricke, William A.; Tagliaferri, Mary; Cohen, Isaac; Bjeldanes, Leonard F.; Leitman, Dale C.

2008-01-01

408

Conventional Therapy and Promising Plant-Derived Compounds Against Trypanosomatid Parasites  

PubMed Central

Leishmaniasis and trypanosomiasis are two neglected and potentially lethal diseases that affect mostly the poor and marginal populations of developing countries around the world and consequently have an important impact on public health. Clinical manifestations such as cutaneous, mucocutaneous, and visceral disorders are the most frequent forms of leishmaniasis, a group of diseases caused by several Leishmania spp. American trypanosomiasis, or Chagas disease, is caused by Trypanosoma cruzi, a parasite that causes progressive damage to different organs, particularly the heart, esophagus, and lower intestine. African trypanosomiasis, or sleeping sickness, is caused by Trypanosoma brucei and is characterized by first presenting as an acute form that affects blood clotting and then becoming a chronic meningoencephalitis. The limited number, low efficacy, and side effects of conventional anti-leishmania and anti-trypanosomal drugs and the resistance developed by parasites are the major factors responsible for the growth in mortality rates. Recent research focused on plants has shown an ingenious way to obtain a solid and potentially rich source of drug candidates against various infectious diseases. Bioactive phytocompounds present in the crude extracts and essential oils of medicinal plants are components of an important strategy linked to the discovery of new medicines. These compounds have proven to be a good source of therapeutic agents for the treatment of leishmaniasis and trypanosomiasis. This work highlights some chemotherapeutic agents while emphasizing the importance of plants as a source of new and powerful drugs against these widespread diseases. PMID:22888328

Alviano, Daniela Sales; Barreto, Anna Léa Silva; Dias, Felipe de Almeida; Rodrigues, Igor de Almeida; Rosa, Maria do Socorro dos Santos; Alviano, Celuta Sales; Soares, Rosangela Maria de Araújo

2012-01-01

409

Ion-Channel Genosensor for the Detection of Specific DNA Sequences Derived from Plum Pox Virus in Plant Extracts  

PubMed Central

A DNA biosensor for detection of specific oligonucleotides sequences of Plum Pox Virus (PPV) in plant extracts and buffer is proposed. The working principles of a genosensor are based on the ion-channel mechanism. The NH2-ssDNA probe was deposited onto a glassy carbon electrode surface to form an amide bond between the carboxyl group of oxidized electrode surface and amino group from ssDNA probe. The analytical signals generated as a result of hybridization were registered in Osteryoung square wave voltammetry in the presence of [Fe(CN)6]3?/4? as a redox marker. The 22-mer and 42-mer complementary ssDNA sequences derived from PPV and DNA samples from plants infected with PPV were used as targets. Similar detection limits of 2.4 pM (31.0 pg/mL) and 2.3 pM (29.5 pg/mL) in the concentration range 1–8 pM were observed in the presence of the 22-mer ssDNA and 42-mer complementary ssDNA sequences of PPV, respectively. The genosensor was capable of discriminating between samples consisting of extracts from healthy plants and leaf extracts from infected plants in the concentration range 10–50 pg/mL. The detection limit was 12.8 pg/mL. The genosensor displayed good selectivity and sensitivity. The 20-mer partially complementary DNA sequences with four complementary bases and DNA samples from healthy plants used as negative controls generated low signal. PMID:25302809

Malecka, Kamila; Michalczuk, Lech; Radecka, Hanna; Radecki, Jerzy

2014-01-01

410

The role of carbon starvation in the induction of enzymes that degrade plant-derived carbohydrates in Aspergillus niger  

PubMed Central

Fungi are an important source of enzymes for saccharification of plant polysaccharides and production of biofuels. Understanding of the regulation and induction of expression of genes encoding these enzymes is still incomplete. To explore the induction mechanism, we analysed the response of the industrially important fungus Aspergillus niger to wheat straw, with a focus on events occurring shortly after exposure to the substrate. RNA sequencing showed that the transcriptional response after 6 h of exposure to wheat straw was very different from the response at 24 h of exposure to the same substrate. For example, less than half of the genes encoding carbohydrate active enzymes that were induced after 24 h of exposure to wheat straw, were also induced after 6 h exposure. Importantly, over a third of the genes induced after 6 h of exposure to wheat straw were also induced during 6 h of carbon starvation, indicating that carbon starvation is probably an important factor in the early response to wheat straw. The up-regulation of the expression of a high number of genes encoding CAZymes that are active on plant-derived carbohydrates during early carbon starvation suggests that these enzymes could be involved in a scouting role during starvation, releasing inducing sugars from complex plant polysaccharides. We show, using proteomics, that carbon-starved cultures indeed release CAZymes with predicted activity on plant polysaccharides. Analysis of the enzymatic activity and the reaction products, indicates that these proteins are enzymes that can degrade various plant polysaccharides to generate both known, as well as potentially new, inducers of CAZymes. PMID:24792495

van Munster, Jolanda M.; Daly, Paul; Delmas, Stéphane; Pullan, Steven T.; Blythe, Martin J.; Malla, Sunir; Kokolski, Matthew; Noltorp, Emelie C.M.; Wennberg, Kristin; Fetherston, Richard; Beniston, Richard; Yu, Xiaolan; Dupree, Paul; Archer, David B.

2014-01-01

411

The role of carbon starvation in the induction of enzymes that degrade plant-derived carbohydrates in Aspergillus niger.  

PubMed

Fungi are an important source of enzymes for saccharification of plant polysaccharides and production of biofuels. Understanding of the regulation and induction of expression of genes encoding these enzymes is still incomplete. To explore the induction mechanism, we analysed the response of the industrially important fungus Aspergillus niger to wheat straw, with a focus on events occurring shortly after exposure to the substrate. RNA sequencing showed that the transcriptional response after 6h of exposure to wheat straw was very different from the response at 24h of exposure to the same substrate. For example, less than half of the genes encoding carbohydrate active enzymes that were induced after 24h of exposure to wheat straw, were also induced after 6h exposure. Importantly, over a third of the genes induced after 6h of exposure to wheat straw were also induced during 6h of carbon starvation, indicating that carbon starvation is probably an important factor in the early response to wheat straw. The up-regulation of the expression of a high number of genes encoding CAZymes that are active on plant-derived carbohydrates during early carbon starvation suggests that these enzymes could be involved in a scouting role during starvation, releasing inducing sugars from complex plant polysaccharides. We show, using proteomics, that carbon-starved cultures indeed release CAZymes with predicted activity on plant polysaccharides. Analysis of the enzymatic activity and the reaction products, indicates that these proteins are enzymes that can degrade various plant polysaccharides to generate both known, as well as potentially new, inducers of CAZymes. PMID:24792495

van Munster, Jolanda M; Daly, Paul; Delmas, Stéphane; Pullan, Steven T; Blythe, Martin J; Malla, Sunir; Kokolski, Matthew; Noltorp, Emelie C M; Wennberg, Kristin; Fetherston, Richard; Beniston, Richard; Yu, Xiaolan; Dupree, Paul; Archer, David B

2014-11-01

412

TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5  

SciTech Connect

This report documents progress made on the subject project during the period of March 1, 2004 through August 31, 2004. The TERESA Study is designed to investigate the role played by specific emissions sources and components in the induction of adverse health effects by examining the relative toxicity of coal combustion and mobile source (gasoline and/or diesel engine) emissions and their oxidative products. The study involves on-site sampling, dilution, and aging of coal combustion emissions at three coal-fired power plants, as well as mobile source emissions, followed by animal exposures incorporating a number of toxicological endpoints. The DOE-EPRI Cooperative Agreement (henceforth referred to as ''the Agreement'') for which this technical progress report has been prepared covers the analysis and interpretation of the field data collected at the first power plant (henceforth referred to as Plant 0, and located in the Upper Midwest), followed by the performance and analysis of similar field experiments at two additional coal-fired power plants (Plants 1 and 2) utilizing different coal types and with different plant configurations. Significant progress was made on the Project during this reporting period, with field work being initiated at Plant 0. Initial testing of the stack sampling system and reaction apparatus revealed that primary particle concentrations were lower than expected in the emissions entering the mobile chemical laboratory. Initial animal exposures to primary emissions were carried out (Scenario 1) to ensure successful implementation of all study methodologies and toxicological assessments. Results indicated no significant toxicological effects in response to primary emissions exposures. Exposures were then carried out to diluted, oxidized, neutralized emissions with the addition of secondary organic aerosol (Scenario 5), both during the day and also at night when primary particle concentrations in the sampled stack emissions tended to be slightly higher. Exposure concentrations were about 249 {micro}g/m{sup 3} PM, of which 87 {micro}g/m{sup 3} was sulfate and approximately 110 {micro}g/m{sup 3} was secondary organic material ({approx}44%). Results indicated subtle differences in breathing pattern between exposed and control (sham) animals, but no differences in other endpoints (in vivo chemiluminescence, blood cytology, bronchoalveolar lavage fluid analysis). It was suspected that primary particle losses may have been occurring in the venturi aspirator/orifice sampler; therefore, the stack sampling system was redesigned. The modified system resulted in no substantial increase in particle concentration in the emissions, leading us to conclude that the electrostatic precipitator at the power plant has high efficiency, and that the sampled emissions are representative of those exiting the stack into the atmosphere. This is important, since the objective of the Project is to carry out exposures to realistic coal combustion-derived secondary PM arising from power plants. During the next reporting period, we will document and describe the remainder of the fieldwork at Plant 0, which we expect to be complete by mid-November 2004. This report will include detailed Phase I toxicological findings for all scenarios run, and Phase II toxicological findings for one selected scenario. Depending upon the outcome of the ongoing fieldwork at Plant 0 (i.e. the biological effects observed), not all the proposed scenarios may be evaluated. The next report is also expected to include preliminary field data for Plant 1, located in the Southeast.

Annette Rohr

2004-12-02

413

Saccharomyces cerevisiae membrane sterol modifications in response to growth in the presence of ethanol  

SciTech Connect

Membranes isolated from yeasts grown in the presence of ethanol do not display the thermally induced transition in diphenylhexatriene anisotropy that is seen in control cells when they are exposed to ethanol in vitro. The total sterol content of the cells that were exposed to ethanol during growth is reduced, with no steryl esters being detected. A greater proportion of the total sterol pool is ergosterol in cells grown in the presence of alcohol. The activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase is reduced by ethanol in vitro. Ethanol-exposed cells take up more exogenous sterol under aerobic conditions than do control cells. The presence of ethanol during growth reduces the activity of the plasma membrane enzyme, chitin synthase, as well as increasing the thermosensitivity of this enzyme.

Walker-Caprioglio, H.M.; Casey, W.M.; Parks, L.W. (North Carolina State Univ., Raleigh (USA))

1990-09-01

414

The major cellular sterol regulatory pathway is required for Andes virus infection.  

PubMed

The Bunyaviridae comprise a large family of RNA viruses with worldwide distribution and includes the pathogenic New World hantavirus, Andes virus (ANDV). Host factors needed for hantavirus entry remain largely enigmatic and therapeutics are unavailable. To identify cellular requirements for ANDV infection, we performed two parallel genetic screens. Analysis of a large library of insertionally mutagenized human haploid cells and a siRNA genomic screen converged on components (SREBP-2, SCAP, S1P and S2P) of the sterol regulatory pathway as critically important for infection by ANDV. The significance of this pathway was confirmed using functionally deficient cells, TALEN-mediated gene disruption, RNA interference and pharmacologic inhibition. Disruption of sterol regulatory complex function impaired ANDV internalization without affecting virus binding. Pharmacologic manipulation of cholesterol levels demonstrated that ANDV entry is sensitive to changes in cellular cholesterol and raises the possibility that clinically approved regulators of sterol synthesis may prove useful for combating ANDV infection. PMID:24516383

Petersen, Josiah; Drake, Mary Jane; Bruce, Emily A; Riblett, Amber M; Didigu, Chukwuka A; Wilen, Craig B; Malani, Nirav; Male, Frances; Lee, Fang-Hua; Bushman, Frederic D; Cherry, Sara; Doms, Robert W; Bates, Paul; Briley, Kenneth

2014-02-01

415

The Major Cellular Sterol Regulatory Pathway Is Required for Andes Virus Infection  

PubMed Central

The Bunyaviridae comprise a large family of RNA viruses with worldwide distribution and includes the pathogenic New World hantavirus, Andes virus (ANDV). Host factors needed for hantavirus entry remain largely enigmatic and therapeutics are unavailable. To identify cellular requirements for ANDV infection, we performed two parallel genetic screens. Analysis of a large library of insertionally mutagenized human haploid cells and a siRNA genomic screen converged on components (SREBP-2, SCAP, S1P and S2P) of the sterol regulatory pathway as critically important for infection by ANDV. The significance of this pathway was confirmed using functionally deficient cells, TALEN-mediated gene disruption, RNA interference and pharmacologic inhibition. Disruption of sterol regulatory complex function impaired ANDV internalization without affecting virus binding. Pharmacologic manipulation of cholesterol levels demonstrated that ANDV entry is sensitive to changes in cellular cholesterol and raises the possibility that clinically approved regulators of sterol synthesis may prove useful for combating ANDV infection. PMID:24516383

Riblett, Amber M.; Didigu, Chukwuka A.; Wilen, Craig B.; Malani, Nirav; Male, Frances; Lee, Fang-Hua; Bushman, Frederic D.; Cherry, Sara; Doms, Robert W.; Bates, Paul; Briley, Kenneth

2014-01-01

416

Enantioseparation and plant virucidal bioactivity of new quinazoline derivatives with ?-aminophosphonate moiety  

Microsoft Academic Search

Enantiomers of some new quinazoline derivatives bearing ?-aminophosphonate moiety were separated under normal-phase conditions on two immobilized polysaccharide-based chiral stationary phases (Chiralpak IA and Chiralpak IC). The role of two chiral stationary phases (CSPs), polar modifier and column temperature on retention time and separation factor was studied. Apparent thermodynamic parameters were deduced from Van’t Hoff plots and plausible mechanism of

Yuping Zhang; Song Bai; Baoan Song; Pinaki S. Bhadury; Deyu Hu; Song Yang; Xiaoyan Zhang; Huitao Fan; Ping Lu

2010-01-01

417

Effect of single and binary combinations of plant-derived molluscicides on reproduction and survival of the snail Achatina fulica.  

PubMed

The effects of sublethal treatments (20% and 60% of LC(50)/24 h) with plant-derived molluscicides on the reproduction of the giant African snail Achatina fulica were studied. Azadirachta indica oil, Cedrus deodara oil, Allium sativum bulb powder, and Nerium indicum bark powder singly and binary combinations on reproduction and survival of A. fulica were investigated. Repeated treatment occurred on day 0, day 15, and day 30. These plant-derived molluscicides significantly reduced fecundity, egg viability, and survival of A. fulica within 15 days. Discontinuation of the treatments after day 30 did not lead to a recovery trend in the next 30 days. Day 0 sublethal