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Hazem A Fahim, Waleed M A El Rouby, Ahmed O El-Gendy, Ahmed S Khairalla, Ibrahim A Naguib, Ahmed A Farghali
Herein, enhancements of the yield and antimicrobial activity duration of the bacteriocin avicin A were accomplished using fractional factorial design (FFD) and layered double hydroxide (LDH) nanoparticles. Firstly, potential factors affecting bacteriocin production were selected for preliminary study. By a 2(5-1) FFD, high pH was shown to have a positive effect on avicin A yield, while temperature and duration of incubation, as well as peptone nitrogen sources all had negative effects. The highest bacteriocin production and activity (2560 BU/ml) were observed after 30 h of incubation at 30 °C, with pH adjustment at 7, and in the presence of 2 g mannitol as carbon source and 2...
September 6, 2017: Scientific Reports
Christopher J Pino, Michael A Scherer, V Prasad Shastri
Percutaneous absorption and transdermal delivery of water-soluble drugs have proven to be challenging due to their low permeability through skin. Avicins which are triterpene saponin glycosides (TSGs) derived from the desert plant Acacia victoriae have not been investigated to date as chemical penetration enhancers due to their higher molecular weight (MW 2,000 Da). It was recently shown that avicins exhibit remarkable mobility across skin lipids in spite of their large size due to their unique chemical structure...
April 2014: Drug Delivery and Translational Research
Denis Castillo, Michel Sauvain, Marion Rivaud, Valérie Jullian
Seven benzo[c]phenanthridines, synthetic or isolated from Zanthoxylum rhoifolium root bark, were evaluated against Leishmania amazonensis axenic amastigotes. Five of them were considered leishmanicidal, with IC50 values ranging from 0.03 to 0.54 µM, and were evaluated on intramacrophagic amastigotes of L. amazonensis. Chelerythrine displayed the best activity (IC50=0.5 µM), which was in the same range as the reference compound amphotericin B (IC50=0.4 µM). In vivo studies with chelerythrine, avicine, and fagaridine on a model of mice cutaneous leishmaniasis resulted in the identification of fagaridine as the most active compound...
July 2014: Planta Medica
Luciana de C Tavares, Graciane Zanon, Andréia D Weber, Alexandre T Neto, Clarice P Mostardeiro, Ivana B M Da Cruz, Raul M Oliveira, Vinicius Ilha, Ionara I Dalcol, Ademir F Morel
Zanthoxylum rhoifolium (Rutaceae) is a plant alkaloid that grows in South America and has been used in Brazilian traditional medicine for the treatment of different health problems. The present study was designed to evaluate the antimicrobial activity of the steam bark crude methanol extract, fractions, and pure alkaloids of Z. rhoifolium. Its stem bark extracts exhibited a broad spectrum of antimicrobial activity, ranging from 12.5 to 100 µg/mL using bioautography method, and from 125 to 500 µg/mL in the microdilution bioassay...
2014: PloS One
Renu Nandakumar, Kesh Talapatra
Bacteriocins are a heterogeneous group of ribosomally synthesized peptides or proteins with antimicrobial activity, produced predominantly by lactic acid bacteria, with potential applications as biopreservatives and probiotics. We describe here a novel strategy based on a bottom-up, shotgun proteomic approach using nanoliquid chromatography-tandem mass spectrometry (nanoLC-MS/MS) with multiple fragmentation techniques for the quantitative profiling of bacteriocins present in the probiotic preparations of Lactobacillus acidophilus...
2014: Journal of Dairy Science
Christopher J Pino, Jordan U Gutterman, Daniel Vonwil, Samir Mitragotri, V Prasad Shastri
Stratum corneum, the outermost layer of skin, allows transport of only low-molecular weight (<500) lipophilic solutes. Here, we report a surprising finding that avicins (Avs), a family of naturally occurring glycosylated triterpenes with a molecular weight > 2,000, exhibit skin permeabilities comparable to those of small hydrophobic molecules, such as estradiol. Systematic fragmentation of the Av molecule shows that deletion of the outer monoterpene results in a 62% reduction in permeability, suggesting an important role for this motif in skin permeation...
December 26, 2012: Proceedings of the National Academy of Sciences of the United States of America
Dagim Jirata Birri, Dag Anders Brede, Girum Tadesse Tessema, Ingolf F Nes
The objective of this study was to characterise lactic acid bacteria (LAB) isolated from faecal samples of healthy Ethiopian infants, with emphasis on bacteriocin production and antibiotic susceptibility. One hundred fifty LAB were obtained from 28 healthy Ethiopian infants. The isolates belonged to Lactobacillus (81/150), Enterococcus (54/150) and Streptococcus (15/150) genera. Lactobacillus species were more abundant in the breast-fed infants while Enterococcus dominated the mixed-fed population. Bacteriocin-producing LAB species were isolated from eight of the infants...
February 2013: Microbial Ecology
Valsala Haridas, Zhi-Xiang Xu, Doug Kitchen, Anna Jiang, Peter Michels, Jordan U Gutterman
Avicins, a family of apoptotic triterpene electrophiles, are known to regulate cellular metabolism and energy homeostasis, by targeting the mitochondria. Having evolved from "ancient hopanoids," avicins bear a structural resemblance with glucocorticoids (GCs), which are the endogenous regulators of metabolism and energy balance. These structural and functional similarities prompted us to compare the mode of action of avicin D with dexamethasone (Dex), a prototypical GC. Using cold competition assay, we show that Avicin D competes with Dex for binding to the GC receptor (GR), leading to its nuclear translocation...
2011: PloS One
Vivek R Yadav, Sahdeo Prasad, Bokyung Sung, Ramaswamy Kannappan, Bharat B Aggarwal
Traditional medicine and diet has served mankind through the ages for prevention and treatment of most chronic diseases. Mounting evidence suggests that chronic inflammation mediates most chronic diseases, including cancer. More than other transcription factors, nuclear factor-kappaB (NF-κB) and STAT3 have emerged as major regulators of inflammation, cellular transformation, and tumor cell survival, proliferation, invasion, angiogenesis, and metastasis. Thus, agents that can inhibit NF-κB and STAT3 activation pathways have the potential to both prevent and treat cancer...
October 2010: Toxins
Pei Lv, Kanglun Huang, Longguan Xie, Xiaohua Xu
A concise and efficient synthesis of benzo[c]phenanthridines was accomplished by the palladium-catalyzed ring-opening coupling of azabicyclic alkene with o-iodobenzoates, followed by tandem cyclization. The strategy was successfully applied in the total synthesis of benzo[c]phenanthridine alkaloids such as sanguinarine, chelerythrine, nitidine and avicine.
May 7, 2011: Organic & Biomolecular Chemistry
Huibo Wang, Valsala Haridas, Jordan U Gutterman, Zhi-Xiang Xu
Avicins, a family of plant-derived triterpenoids, have been shown to possess pro-apoptotic, anti-mutagenic and anti-inflammatory properties in mammalian cells. Through thiol binding, avicins can also mediate antioxidant defense. Accumulating evidence uncovered during the past several years suggests that avicins induce tumor cell death via multiple mechanisms. This review will focus on recent studies that provide insights into the cellular and molecular processes and pathways by which avicins induce tumor cell death, including the canonical intrinsic mitochondrial and the Fas-mediated apoptosis cascades as well as autophagy-associated non-apoptotic programmed cell death...
May 2010: Communicative & Integrative Biology
Shuli Man, Wenyuan Gao, Yanjun Zhang, Luqi Huang, Changxiao Liu
Saponins are a group of naturally occurring plant glycosides, characterized by their strong foam-forming properties in aqueous solution. The presence of saponins has been reported in more than 100 families of plants out of which at least 150 kinds of natural saponins have been found to possess significant anti-cancer properties. There are more than 11 distinguished classes of saponins including dammaranes, tirucallanes, lupanes, hopanes, oleananes, taraxasteranes, ursanes, cycloartanes, lanostanes, cucurbitanes and steroids...
October 2010: Fitoterapia
Mauricio Arias, Jairo C Quijano, Valsala Haridas, Jordan U Gutterman, Victor V Lemeshko
Plasma membrane permeabilization by saponin and anticancer avicins was studied using light dispersion measurements, since high correlation between light dispersion changes and hemolysis has been demonstrated. Nevertheless, we observed that rat red blood cell swelling in moderately hypotonic media was accompanied by up to 20% decrease of light dispersion, when hemolysis was not yet detectable. Avicin G and avicin D were significantly more efficient than saponin in inducing cytotoxicity in PC3 human prostate cancer cells...
June 2010: Biochimica et Biophysica Acta
Zhi-Xiang Xu, Tian Ding, Valsala Haridas, Fiona Connolly, Jordan U Gutterman
Avicins, a family of triterpene electrophiles originally identified as potent inhibitors of tumor cell growth, have been shown to be pleiotropic compounds that also possess antioxidant, anti-mutagenic, and anti-inflammatory activities. We previously showed that Jurkat cells, which express a high level of Fas, are very sensitive to treatment with avicins. Thus, we hypothesized that avicins may induce cell apoptosis by activation of the Fas pathway. By using a series of cell lines deficient in cell death receptors, we demonstrated that upon avicin D treatment, Fas translocates to the cholesterol- and sphingolipid-enriched membrane microdomains known as lipid rafts...
December 31, 2009: PloS One
Dagim Jirata Birri, Dag A Brede, Torunn Forberg, Helge Holo, Ingolf F Nes
Enterococci are among the most common human intestinal lactic acid bacteria, and they are known to produce bacteriocins. In this study, fecal enterococci were isolated from infants and screened for bacteriocin production. Bacteriocin-producing Enterococcus avium isolates were obtained, and a new pediocin-like bacteriocin was purified and characterized. This bacteriocin, termed avicin A, was found to be produced by isolates from two healthy infants. It was purified to homogeneity from culture supernatant by ion-exchange and reversed-phase chromatography, and part of its amino acid sequence was obtained...
January 2010: Applied and Environmental Microbiology
Alessia Petronelli, Gaetano Pannitteri, Ugo Testa
Triterpenoids are structurally diverse organic compounds, characterized by a basic backbone modified in multiple ways, allowing the formation of more than 20 000 naturally occurring triterpenoid varieties. Several triterpenoids, including ursolic and oleanolic acid, betulinic acid, celastrol, pristimerin, lupeol, and avicins possess antitumor and anti-inflammatory properties. To improve antitumor activity, some synthetic triterpenoid derivatives have been synthesized, including cyano-3,12-dioxooleana-1,9 (11)-dien-28-oic (CDDO), its methyl ester (CDDO-Me), and imidazolide (CDDO-Im) derivatives...
November 2009: Anti-cancer Drugs
Valsala Haridas, Goshi Nishimura, Zhi-Xiang Xu, Fiona Connolly, Margaret Hanausek, Zbigniew Walaszek, Robert Zoltaszek, Jordan U Gutterman
Avicins, a class of electrophilic triterpenoids with pro-apoptotic, anti-inflammatory and antioxidant properties, have been shown to induce redox-dependant post-translational modification of cysteine residues to regulate protein function. Based on (a) the cross-talk that occurs between redox and phosphorylation processes, and (b) the role of Stat3 in the process of apoptosis and carcinogenesis, we chose to study the effects of avicins on the processes of phosphorylation/dephosphorylation in Stat3. Avicins dephosphorylate Stat3 in a variety of human tumor cell lines, leading to a decrease in the transcriptional activity of Stat3...
2009: PloS One
Christopher Bachran, Silke Bachran, Mark Sutherland, Diana Bachran, Hendrik Fuchs
Saponins are plant glycosides with favorable anti-tumorigenic properties. Several saponins inhibit tumor cell growth by cell cycle arrest and apoptosis with IC50 values of up to 0.2 microM. We discuss diverse groups of saponins (dioscins, saikosaponins, julibrosides, soy saponins, ginseng saponins and avicins) investigated in relation to tumor therapy and focus on cellular and systemic mechanisms of tumor cell growth inhibition both in vitro and in vivo. The review also describes saponins in combination with conventional tumor treatment strategies, which result in improved therapeutic success...
June 2008: Mini Reviews in Medicinal Chemistry
Chunlei Zhang, Baoqiang Li, Amos S Gaikwad, Valsala Haridas, Zhixiang Xu, Jordan U Gutterman, Madeleine Duvic
Avicin D, a natural triterpenoid saponin, inhibits cell growth and induces apoptosis in transformed tumor cell lines in vitro and mouse skin carcinogenesis models in vivo. To investigate the anti-tumor effects of avicin D in cutaneous T-cell lymphomas (CTCL), we compared three CTCL cell lines and Sézary cells from three Sézary syndrome (SS) patients with normal CD4+ and activated CD4+ T cells from three healthy donors. Avicin D at 0.5-5 mug ml(-1) induced apoptosis in a time- and dose-dependent manner in three cell lines: MJ (-0...
November 2008: Journal of Investigative Dermatology
Z-X Xu, J Liang, V Haridas, A Gaikwad, F P Connolly, G B Mills, J U Gutterman
Avicins, a family of plant triterpene electrophiles, can trigger apoptosis-associated tumor cell death, and suppress chemical-induced carcinogenesis by its anti-inflammatory, anti-mutagenic, and antioxidant properties. Here, we show that tumor cells treated with benzyloxycarbonylvalyl-alanyl-aspartic acid (O-methyl)-fluoro-methylketone, an apoptosis inhibitor, and Bax(-/-)Bak(-/-) apoptosis-resistant cells can still undergo cell death in response to avicin D treatment. We demonstrate that this non-apoptotic cell death is mediated by autophagy, which can be suppressed by chloroquine, an autophagy inhibitor, and by specific knockdown of autophagy-related gene-5 (Atg5) and Atg7...
November 2007: Cell Death and Differentiation
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