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Usama Ramadan Abdelmohsen - One of the best experts on this subject based on the ideXlab platform.
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antifungal potential of Marine Natural Products
Social Science Research Network, 2021Co-Authors: Ebaa M Elhossary, Usama Ramadan Abdelmohsen, Cheng Cheng, Mostafa M Hamed, Ashraf Hamed, Knut Ohlsen, Ute HentschelAbstract:Fungal diseases represent an increasing threat to human health worldwide which in some cases might be associated with substantial morbidity and mortality. However, only few antifungal drugs are currently available for the treatment of life-threatening fungal infections. Furthermore, plant diseases caused by fungal pathogens represent a worldwide economic problem for the agriculture industry. The Marine environment continues to provide structurally diverse and biologically active secondary metabolites, several of which have inspired the development of new classes of therapeutic agents. Among these secondary metabolites, several compounds with noteworthy antifungal activities have been isolated from Marine microorganisms, invertebrates, and algae. During the last fifteen years, around 65% of Marine Natural Products possessing antifungal activities have been isolated from sponges and bacteria. This review gives an overview of Natural Products from diverse Marine organisms that have shown in vitro and/or in vivo potential as antifungal agents, with their mechanism of action whenever applicable. The Natural Products literature is covered from January 2000 until June 2015, and we are reporting the chemical structures together with their biological activities, as well as the isolation source.
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Marine Natural Products from sponges porifera of the order dictyoceratida 2013 to 2019 a promising source for drug discovery
RSC Advances, 2020Co-Authors: Enas R Abdelaleem, Mamdouh Nabil Samy, Samar Yehia Desoukey, Miaomiao Liu, Ronald J Quinn, Usama Ramadan AbdelmohsenAbstract:Marine organisms have been considered an interesting target for the discovery of different classes of secondary Natural Products with wide-ranging biological activities. Sponges which belong to the order Dictyoceratida are distinctly classified into 5 families: Dysideidae, Irciniidae, Spongiidae, Thorectidae, and Verticilliitidae. In this review, compounds isolated from Dictyoceratida sponges were discussed with their biological potential within the period 2013 to December 2019. Moreover, analysis of the physicochemical properties of these Marine Natural Products was investigated and the results showed that 78% of the compounds have oral bioavailability potential. This review highlights sponges of the order Dictyoceratida as exciting source for discovery of new drug leads.
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potential of Marine Natural Products against drug resistant bacterial infections
Lancet Infectious Diseases, 2019Co-Authors: Miaomiao Liu, Ronald J Quinn, Ebaa M Elhossary, Tobias A Oelschlaeger, Mohamed Abou S Donia, Usama Ramadan AbdelmohsenAbstract:Natural Products have been a rich source of compounds with structural and chemical diversity for drug discovery. However, antibiotic resistance in bacteria has been reported for nearly every antibiotic once it is used in clinical practice. In the past decade, pharmaceutical companies have reduced their Natural product discovery projects because of challenges, such as high costs, low return rates, and high rediscovery rates. The largely unexplored Marine environment harbours substantial diversity and is a large resource to discover novel compounds with novel modes of action, which is essential for the treatment of drug-resistant bacterial infections. In this Review, we report compounds derived from Marine sources that have shown in-vivo and in-vitro efficacy against drug-resistant bacteria. Analysis of the physicochemical properties of these Marine Natural Products with activity against drug-resistant bacteria showed that 60% of the compounds have oral bioavailability potential. Their overall distribution pattern of drug characteristics agrees with the observation that marketed antibacterial drugs have a polar distribution, with a lower median calculated logP. The aim of this Review is to summarise the diversity of these Marine Natural Products, with a special focus on analysis of drug bioavailability. Such biologically active compounds, with high degrees of bioavailability, have the potential to be developed as effective drugs against infectious diseases.
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antifungal potential of Marine Natural Products
European Journal of Medicinal Chemistry, 2017Co-Authors: Ebaa M Elhossary, Usama Ramadan Abdelmohsen, Cheng Cheng, Mostafa M Hamed, Ashraf Hamed, Knut Ohlsen, Ute HentschelAbstract:Highlights: • Fungal infections represent an increasing threat to human health. • Fungal infections in plants are a worldwide problem to the agricultural industry. • Diverse antifungal compounds were isolated from different Marine organisms. • The number of new antifungal Marine Natural Products is rapidly developing. • Marine sponges and bacteria are the predominant sources for antifungal compounds. Abstract: Fungal diseases represent an increasing threat to human health worldwide which in some cases might be associated with substantial morbidity and mortality. However, only few antifungal drugs are currently available for the treatment of life-threatening fungal infections. Furthermore, plant diseases caused by fungal pathogens represent a worldwide economic problem for the agriculture industry. The Marine environment continues to provide structurally diverse and biologically active secondary metabolites, several of which have inspired the development of new classes of therapeutic agents. Among these secondary metabolites, several compounds with noteworthy antifungal activities have been isolated from Marine microorganisms, invertebrates, and algae. During the last fifteen years, around 65% of Marine Natural Products possessing antifungal activities have been isolated from sponges and bacteria. This review gives an overview of Natural Products from diverse Marine organisms that have shown in vitro and/or in vivo potential as antifungal agents, with their mechanism of action whenever applicable. The Natural Products literature is covered from January 2000 until June 2015, and we are reporting the chemical structures together with their biological activities, as well as the isolation source.
Alison Butler - One of the best experts on this subject based on the ideXlab platform.
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vanadium bromoperoxidase catalyzed biosynthesis of halogenated Marine Natural Products
Journal of the American Chemical Society, 2004Co-Authors: Jayme N Carterfranklin, Alison ButlerAbstract:Marine red algae (Rhodophyta) are a rich source of bioactive halogenated Natural Products. The biogenesis of the cyclic halogenated terpene Marine Natural Products, in particular, has attracted sustained interest in part because terpenes are the biogenic precursors of many bioactive metabolites. The first enzymatic asymmetric bromination and cyclization of a terpene, producing Marine Natural Products isolated from red algae, is reported. Vanadium bromoperoxidase (V-BrPO) isolated from Marine red algae (species of Laurencia, Plocamium, Corallina) catalyzes the bromination of the sesquiterpene (E)-(+)-nerolidol producing R-, ‚-, and A-snyderol and (+)-3‚-bromo-8-epicaparrapi oxide. R-Snyderol, ‚-snyderol, and (+)- 3‚-bromo-8-epicaparrapi oxide have been isolated from Laurencia obtusa, and each have also been isolated from other species of Marine red algae. A-Snyderol is a proposed intermediate in other bicyclo Natural Products. Single diastereomers of ‚-snyderol, A-snyderol, and mixed diastereomers of (+)-3‚-bromo-8- epicaparrapi oxide (de ) 20-25%) are produced in the enzyme reaction, whereas two diastereomers of these compounds are formed in the synthesis with 2,4,4,6-tetrabromocyclohexa-2,5-dienone (TBCO). V-BrPO likely functions by catalyzing the two-electron oxidation of bromide ion by hydrogen peroxide producing a bromonium ion or equivalent in the active site that brominates one face of the terminal olefin of nerolidol. These results establish V-BrPO's role in the biosynthesis of brominated cyclic sesquiterpene structures from Marine red algae for the first time.
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vanadium bromoperoxidase catalyzed biosynthesis of halogenated Marine Natural Products
Journal of the American Chemical Society, 2004Co-Authors: Jayme N Carterfranklin, Alison ButlerAbstract:Marine red algae (Rhodophyta) are a rich source of bioactive halogenated Natural Products. The biogenesis of the cyclic halogenated terpene Marine Natural Products, in particular, has attracted sustained interest in part because terpenes are the biogenic precursors of many bioactive metabolites. The first enzymatic asymmetric bromination and cyclization of a terpene, producing Marine Natural Products isolated from red algae, is reported. Vanadium bromoperoxidase (V-BrPO) isolated from Marine red algae (species of Laurencia, Plocamium, Corallina) catalyzes the bromination of the sesquiterpene (E)-(+)-nerolidol producing α-, β-, and γ-snyderol and (+)-3β-bromo-8-epicaparrapi oxide. α-Snyderol, β-snyderol, and (+)-3β-bromo-8-epicaparrapi oxide have been isolated from Laurencia obtusa, and each have also been isolated from other species of Marine red algae. γ-Snyderol is a proposed intermediate in other bicyclo Natural Products. Single diastereomers of β-snyderol, γ-snyderol, and mixed diastereomers of (+)-3β...
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the role of vanadium bromoperoxidase in the biosynthesis of halogenated Marine Natural Products
Natural Product Reports, 2004Co-Authors: Alison Butler, Jayme N CarterfranklinAbstract:Covering: 1998–2003 Halogenated Natural Products are frequently reported metabolites in Marine seaweeds. These compounds span a range from halogenated indoles, terpenes, acetogenins, phenols, etc., to volatile halogenated hydrocarbons that are produced on a very large scale. In many cases these halogenated Marine metabolites possess biological activities of pharmacological interest. Given the abundance of halogenated Marine Natural Products found in Marine organisms and their potentially important biological activities, the biogenesis of these compounds has intrigued Marine Natural product chemists for decades. Over a quarter of a century ago, a possible role for haloperoxidase enzymes was first suggested in the biogenesis of certain halogenated Marine Natural Products, although this was long before haloperoxidases were discovered in Marine organisms. Since that time, FeHeme- and Vanadium-haloperoxidases (V-HPO) have been discovered in many Marine organisms. The structure and catalytic activity of vanadium haloperoxidases is reviewed herein, including the importance of V-HPO-catalyzed bromination and cyclization of terpene substrates.
Jayme N Carterfranklin - One of the best experts on this subject based on the ideXlab platform.
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vanadium bromoperoxidase catalyzed biosynthesis of halogenated Marine Natural Products
Journal of the American Chemical Society, 2004Co-Authors: Jayme N Carterfranklin, Alison ButlerAbstract:Marine red algae (Rhodophyta) are a rich source of bioactive halogenated Natural Products. The biogenesis of the cyclic halogenated terpene Marine Natural Products, in particular, has attracted sustained interest in part because terpenes are the biogenic precursors of many bioactive metabolites. The first enzymatic asymmetric bromination and cyclization of a terpene, producing Marine Natural Products isolated from red algae, is reported. Vanadium bromoperoxidase (V-BrPO) isolated from Marine red algae (species of Laurencia, Plocamium, Corallina) catalyzes the bromination of the sesquiterpene (E)-(+)-nerolidol producing R-, ‚-, and A-snyderol and (+)-3‚-bromo-8-epicaparrapi oxide. R-Snyderol, ‚-snyderol, and (+)- 3‚-bromo-8-epicaparrapi oxide have been isolated from Laurencia obtusa, and each have also been isolated from other species of Marine red algae. A-Snyderol is a proposed intermediate in other bicyclo Natural Products. Single diastereomers of ‚-snyderol, A-snyderol, and mixed diastereomers of (+)-3‚-bromo-8- epicaparrapi oxide (de ) 20-25%) are produced in the enzyme reaction, whereas two diastereomers of these compounds are formed in the synthesis with 2,4,4,6-tetrabromocyclohexa-2,5-dienone (TBCO). V-BrPO likely functions by catalyzing the two-electron oxidation of bromide ion by hydrogen peroxide producing a bromonium ion or equivalent in the active site that brominates one face of the terminal olefin of nerolidol. These results establish V-BrPO's role in the biosynthesis of brominated cyclic sesquiterpene structures from Marine red algae for the first time.
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vanadium bromoperoxidase catalyzed biosynthesis of halogenated Marine Natural Products
Journal of the American Chemical Society, 2004Co-Authors: Jayme N Carterfranklin, Alison ButlerAbstract:Marine red algae (Rhodophyta) are a rich source of bioactive halogenated Natural Products. The biogenesis of the cyclic halogenated terpene Marine Natural Products, in particular, has attracted sustained interest in part because terpenes are the biogenic precursors of many bioactive metabolites. The first enzymatic asymmetric bromination and cyclization of a terpene, producing Marine Natural Products isolated from red algae, is reported. Vanadium bromoperoxidase (V-BrPO) isolated from Marine red algae (species of Laurencia, Plocamium, Corallina) catalyzes the bromination of the sesquiterpene (E)-(+)-nerolidol producing α-, β-, and γ-snyderol and (+)-3β-bromo-8-epicaparrapi oxide. α-Snyderol, β-snyderol, and (+)-3β-bromo-8-epicaparrapi oxide have been isolated from Laurencia obtusa, and each have also been isolated from other species of Marine red algae. γ-Snyderol is a proposed intermediate in other bicyclo Natural Products. Single diastereomers of β-snyderol, γ-snyderol, and mixed diastereomers of (+)-3β...
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the role of vanadium bromoperoxidase in the biosynthesis of halogenated Marine Natural Products
Natural Product Reports, 2004Co-Authors: Alison Butler, Jayme N CarterfranklinAbstract:Covering: 1998–2003 Halogenated Natural Products are frequently reported metabolites in Marine seaweeds. These compounds span a range from halogenated indoles, terpenes, acetogenins, phenols, etc., to volatile halogenated hydrocarbons that are produced on a very large scale. In many cases these halogenated Marine metabolites possess biological activities of pharmacological interest. Given the abundance of halogenated Marine Natural Products found in Marine organisms and their potentially important biological activities, the biogenesis of these compounds has intrigued Marine Natural product chemists for decades. Over a quarter of a century ago, a possible role for haloperoxidase enzymes was first suggested in the biogenesis of certain halogenated Marine Natural Products, although this was long before haloperoxidases were discovered in Marine organisms. Since that time, FeHeme- and Vanadium-haloperoxidases (V-HPO) have been discovered in many Marine organisms. The structure and catalytic activity of vanadium haloperoxidases is reviewed herein, including the importance of V-HPO-catalyzed bromination and cyclization of terpene substrates.
Mark T. Hamann - One of the best experts on this subject based on the ideXlab platform.
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role of Marine Natural Products in the genesis of antiviral agents
Chemical Reviews, 2015Co-Authors: Vedanjali Gogineni, Raymond F Schinazi, Mark T. HamannAbstract:Mammals have complex biological systems and are constantly prone to infections by a wide array of bacteria, fungi, viruses, and parasites, a significant challenge to the constant development of disease-strains resistance to current drugs.1 As a result, there is always a need to identify new anti-infective agents against these organisms. An anti-infective agent is defined by Webster as “an agent capable of acting against an infection, by inhibiting the spread of an infectious agent or by killing the infectious agent outright”.2 Some of the emerging and drug-resistant infectious diseases having research priority are human immunodeficiency virus (HIV) or AIDS, hepatitis B and C viruses, respiratory infections such as influenza and respiratory syncytial virus (RSV), and dengue fever.1 Figures 1 and and22 provide us with the data in regards to the mortality and incidence rates, respectively, of people with viral diseases.3–5 Figure 1 Mortality versus viral diseases.3–5 Figure 2 Incidence rates versus viral diseases.3–5 Search engines utilized to identify the literature reviewed here include Google scholar, Scifinder, Pubmed, government documents from the CDC, NIH, and the World Health Organization (WHO), academic journals, and books.
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indole alkaloid Marine Natural Products an established source of cancer drug leads with considerable promise for the control of parasitic neurological and other diseases
Life Sciences, 2005Co-Authors: Waseem Gul, Mark T. HamannAbstract:The Marine environment produces Natural Products from a variety of structural classes exhibiting activity against numerous disease targets. Historically Marine Natural Products have largely been explored as anticancer agents. The indole alkaloids are a class of Marine Natural Products that show unique promise in the development of new drug leads. This report reviews the literature on indole alkaloids of Marine origin and also highlights our own research. Specific biological activities of indole alkaloids presented here include: cytotoxicity, antiviral, antiparasitic, anti-inflammatory, serotonin antagonism, Ca-releasing, calmodulin antagonism, and other pharmacological activities.
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Marine Natural Products as novel antioxidant prototypes
Journal of Natural Products, 2003Co-Authors: Satoshi Takamatsu, Mark T. Hamann, William H. Gerwick, Tyler W Hodges, Ira Rajbhandari, Dale G NagleAbstract:Pure Natural Products isolated from Marine sponges, algae, and cyanobacteria were examined for antioxidant activity using a 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) solution-based chemical assay and a 2‘,7‘-dichlorodihydrofluorescein diacetate (DCFH-DA) cellular-based assay. The DCFH system detects only antioxidants that penetrate cellular membranes. Potent antioxidants were identified and the results from each system compared. The algal metabolites cymopol (1), avrainvilleol (3), and fragilamide (4), and the invertebrate constituent puupehenone (5) showed strong antioxidant activity in both systems. Several compounds were active in the DPPH assay but significantly less active in the DCFH system. The green algal metabolite 7-hydroxycymopol (2) was isolated from Cymopolia barbata and its structure determined. Compound 2 was significantly less active in the DCFH system than cymopol (1). The sponge metabolites (1S)-(+)-curcuphenol (6), aaptamine (7), isoaaptamine (8), and curcudiol (9) and the cyanobacte...
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Marine Natural Products and their potential applications as anti-infective agents.
The Lancet. Infectious diseases, 2003Co-Authors: Marwa S. Donia, Mark T. HamannAbstract:The oceans are a unique resource that provide a diverse array of Natural Products, primarily from invertebrates such as sponges, tunicates, bryozoans, and molluscs, and from Marine bacteria and cyanobacteria. As infectious diseases evolve and develop resistance to existing pharmaceuticals, the Marine environment provides novel leads against fungal, parasitic, bacterial, and viral diseases. Many Marine Natural Products have successfully advanced to the late stages of clinical trials, including dolastatin 10, ecteinascidin-743, kahalalide F, and aplidine, and a growing number of candidates have been selected as promising leads for extended preclinical assessment. Although many Marine-product clinical trials are for cancer chemotherapy, drug resistance, emerging infectious diseases, and the threat of bioterrorism have all contributed to the interest in assessing Natural ocean Products in the treatment of infectious organisms. In this review, we focus on the pharmacologically tested Marine leads that have shown in-vivo efficacy or potent in-vitro activity against infectious and parasitic diseases.
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Marine Natural Products as antituberculosis agents
Tetrahedron, 2000Co-Authors: Khalid El A Sayed, Piotr Bartyzel, Xiaoyu Shen, Tony L Perry, Jordan K Zjawiony, Mark T. HamannAbstract:Abstract In an attempt to characterize additional structural classes that could serve as lead antituberculosis agents, 48 structurally diverse Marine-derived Natural and semisynthetic compounds were examined for in vitro activity against Mycobacterium tuberculosis . Three new classes of compounds including C-19 hydroxy steroids, scalarin sesquiterpenoids and tetrabromo spirocyclohexadienylisoxazolines have been identified as having potential as leads for continued investigations as new antituberculosis agents. New additions to the established antituberculosis structural classes quinone-methide and peptide are also reported.
Hiroyuki Konno - One of the best experts on this subject based on the ideXlab platform.
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total synthesis of callipeltin b and m peptidyl Marine Natural Products
ChemInform, 2015Co-Authors: Mari Kikuchi, Hiroyuki KonnoAbstract:The total synthesis of linear callipeltin M (I) and cyclic callipeltin B (II) by the combination of Fmac solid-phase peptide synthesis and cyclization and deprotection in solution phase is described.
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total synthesis of callipeltin b and m peptidyl Marine Natural Products
Organic Letters, 2014Co-Authors: Mari Kikuchi, Hiroyuki KonnoAbstract:Total synthesis of callipeltins B and M, peptidyl cytotoxic agents isolated from Marine sponges, by the combination of Fmoc solid-phase peptide synthesis and cyclization and global deprotection in the solution phase is described. Eight amino acids, including several unusual amino acids, were assembled on a solid support, and effective TFA-mediated deprotection was employed to reach callipeltin M. Callipeltin B was accomplished via the macrolactonization between the side chain of d-aThr and the C-terminus carboxylic acid of protected callipeltin M.
