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Amal H. Aly

Bio: Amal H. Aly is an academic researcher from University of Düsseldorf. The author has contributed to research in topics: Environmentally friendly & Geopolymer. The author has an hindex of 29, co-authored 51 publications receiving 3671 citations.

Papers published on a yearly basis

Papers
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Journal ArticleDOI
TL;DR: This overview will highlight the chemical potential of endophytic fungi with focus on the detection of pharmaceutically valuable plant constituents, e.g. paclitaxel, camptothecin and podophyllotoxin, as products of fungal biosynthesis, and new bioactive metabolites reported in recent years from fungal endophytes of terrestrial and mangrove plants.
Abstract: Bioactive natural products from endophytic fungi, isolated from higher plants, are attracting considerable attention from natural product chemists and biologists alike as indicated by the steady increase of publications devoted to this topic during recent years (113 research articles on secondary metabolites from endophytic fungi in the period of 2008–2009, 69 in 2006–2007, 36 in 2004–2005, 14 in 2002–2003, and 18 in 2000–2001). This overview will highlight the chemical potential of endophytic fungi with focus on the detection of pharmaceutically valuable plant constituents, e.g. paclitaxel, camptothecin and podophyllotoxin, as products of fungal biosynthesis. In addition, it will cover new bioactive metabolites reported in recent years (2008–2009) from fungal endophytes of terrestrial and mangrove plants. The presented compounds are selected based on their antimicrobial, antiparasitic, cytotoxic as well as neuroprotective activities. Furthermore, possible factors influencing natural product production in endophytes cultivated in vitro and hence the success of bioprospecting from endophytes are likewise discussed in this review.

558 citations

Journal ArticleDOI
TL;DR: The chemical potential of endophytic fungi for drug discovery will be discussed with focus on the detection of pharmaceutically valuable plant constituents as products of fungal biosynthesis.
Abstract: Fungal endophytes residing in the internal tissues of living plants occur in almost every plant on earth from the arctic to the tropics. The endophyte–host relationship is described as a balanced symbiotic continuum ranging from mutualism through commensalism to parasitism. This overview will highlight selected aspects of endophyte diversity, host specificity, endophyte–host interaction and communication as well as regulation of secondary metabolite production with emphasis on advanced genomic methods and their role in improving our current knowledge of endophytic associations. Furthermore, the chemical potential of endophytic fungi for drug discovery will be discussed with focus on the detection of pharmaceutically valuable plant constituents as products of fungal biosynthesis. In addition, selected examples of bioactive metabolites reported in recent years (2008–2010) from fungal endophytes residing in terrestrial plants are presented grouped according to their reported biological activities.

526 citations

Journal ArticleDOI
TL;DR: This protocol gives a detailed description of methods useful for the isolation and cultivation of fungi associated with various marine organisms for the extraction, characterization and structure elucidation of biologically active secondary metabolites produced by these marine-derived endophytic fungi.
Abstract: Marine-derived fungi have been shown in recent years to produce a plethora of new bioactive secondary metabolites, some of them featuring new carbon frameworks hitherto unprecedented in nature. These compounds are of interest as new lead structures for medicine as well as for plant protection. The aim of this protocol is to give a detailed description of methods useful for the isolation and cultivation of fungi associated with various marine organisms (sponges, algae and mangrove plants) for the extraction, characterization and structure elucidation of biologically active secondary metabolites produced by these marine-derived endophytic fungi, and for the preliminary evaluation of their pharmacological properties based on rapid 'in house' screening systems. Some results exemplifying the positive outcomes of the protocol are given at the end. From sampling in marine environment to completion of the structure elucidation and bioactivity screening, a period of at least 3 months has to be scheduled.

367 citations

Journal ArticleDOI
TL;DR: This review covers new biologically active natural products published recently and highlights the chemical potential of marine microorganisms, with focus on bioactive products as well as on their mechanisms of action.
Abstract: Summary Marine bacteria and fungi are of considerable importance as new promising sources of a huge number of biologically active products. Some of these marine species live in a stressful habitat, under cold, lightless and high pressure conditions. Surprisingly, a large number of species with high diversity survive under such conditions and produce fascinating and structurally complex natural products. Up till now, only a small number of microorganisms have been investigated for bioactive metabolites, yet a huge number of active substances with some of them featuring unique structural skeletons have been isolated. This review covers new biologically active natural products published recently (2007–09) and highlights the chemical potential of marine microorganisms, with focus on bioactive products as well as on their mechanisms of action.

299 citations

Journal ArticleDOI
TL;DR: This review highlights the power of co-cultivation for increasing the chemical diversity of bacteria and fungi drawing on published studies from the marine and from the terrestrial habitat alike.
Abstract: Marine-derived bacteria and fungi are promising sources of novel bioactive compounds that are important for drug discovery programs. However, as encountered in terrestrial microorganisms there is a high rate of redundancy that results in the frequent re-discovery of known compounds. Apparently only a part of the biosynthetic genes that are harbored by fungi and bacteria are transcribed under routine laboratory conditions which involve cultivation of axenic microbial strains. Many biosynthetic genes remain silent and are not expressed in vitro thereby seriously limiting the chemical diversity of microbial compounds that can be obtained through fermentation. In contrast to this, co-cultivation (also called mixed fermentation) of two or more different microorganisms tries to mimic the ecological situation where microorganisms always co-exist within complex microbial communities. The competition or antagonism experienced during co-cultivation is shown to lead to a significantly enhanced production of constitutively present compounds and/or to an accumulation of cryptic compounds that are not detected in axenic cultures of the producing strain. This review highlights the power of co-cultivation for increasing the chemical diversity of bacteria and fungi drawing on published studies from the marine and from the terrestrial habitat alike.

273 citations


Cited by
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Journal ArticleDOI
TL;DR: This review covers the literature published in 2014 for marine natural products, with 1116 citations referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms.

4,649 citations

Journal ArticleDOI
TL;DR: This work reviews strategies for natural product screening that harness the recent technical advances that have reduced technical barriers and assess the use of genomic and metabolomic approaches to augment traditional methods of studying natural products.
Abstract: Natural products have been a rich source of compounds for drug discovery. However, their use has diminished in the past two decades, in part because of technical barriers to screening natural products in high-throughput assays against molecular targets. Here, we review strategies for natural product screening that harness the recent technical advances that have reduced these barriers. We also assess the use of genomic and metabolomic approaches to augment traditional methods of studying natural products, and highlight recent examples of natural products in antimicrobial drug discovery and as inhibitors of protein-protein interactions. The growing appreciation of functional assays and phenotypic screens may further contribute to a revival of interest in natural products for drug discovery.

1,822 citations

Journal ArticleDOI
TL;DR: While the intrinsic complexity of natural product-based drug discovery necessitates highly integrated interdisciplinary approaches, the reviewed scientific developments, recent technological advances, and research trends clearly indicate that natural products will be among the most important sources of new drugs in the future.

1,760 citations

Journal ArticleDOI
TL;DR: This review addresses the concept of endophytism, considering the latest insights into evolution, plant ecosystem functioning, and multipartite interactions.
Abstract: All plants are inhabited internally by diverse microbial communities comprising bacterial, archaeal, fungal, and protistic taxa. These microorganisms showing endophytic lifestyles play crucial roles in plant development, growth, fitness, and diversification. The increasing awareness of and information on endophytes provide insight into the complexity of the plant microbiome. The nature of plant-endophyte interactions ranges from mutualism to pathogenicity. This depends on a set of abiotic and biotic factors, including the genotypes of plants and microbes, environmental conditions, and the dynamic network of interactions within the plant biome. In this review, we address the concept of endophytism, considering the latest insights into evolution, plant ecosystem functioning, and multipartite interactions.

1,677 citations

Journal ArticleDOI
28 Jul 2016-Nature
TL;DR: It is shown that nasal Staphylococcus lugdunensis strains produce lugdunin, a novel thiazolidine-containing cyclic peptide antibiotic that prohibits colonization by S. aureus, and a rare example of a non-ribosomally synthesized bioactive compound from human-associated bacteria.
Abstract: The nasal commensal bacterium Staphylococcus lugdunensis produces a novel cyclic peptide antibiotic, lugdunin, that inhibits colonization by S. aureus in animal models and is associated with a significantly reduced S. aureus carriage rate in humans, suggesting that human commensal bacteria could be a valuable resource for the discovery of new antibiotics. The vast majority of systemic bacterial infections are caused by facultative, often antibiotic-resistant, pathogens colonizing human body surfaces. Nasal carriage of Staphylococcus aureus predisposes to invasive infection, but the mechanisms that permit or interfere with pathogen colonization are largely unknown. Whereas soil microbes are known to compete by production of antibiotics, such processes have rarely been reported for human microbiota. We show that nasal Staphylococcus lugdunensis strains produce lugdunin, a novel thiazolidine-containing cyclic peptide antibiotic that prohibits colonization by S. aureus, and a rare example of a non-ribosomally synthesized bioactive compound from human-associated bacteria. Lugdunin is bactericidal against major pathogens, effective in animal models, and not prone to causing development of resistance in S. aureus. Notably, human nasal colonization by S. lugdunensis was associated with a significantly reduced S. aureus carriage rate, suggesting that lugdunin or lugdunin-producing commensal bacteria could be valuable for preventing staphylococcal infections. Moreover, human microbiota should be considered as a source for new antibiotics. The majority of systemic bacterial infections are caused by endogenous pathogens from human microbiota, and the opportunistic pathogen Staphylococcus aureus, commonly found in the external opening of the nostrils, is one of the most clinically important because of the prevalence of multi-drug resistant strains. The mechanisms that permit or interfere with pathogen colonization have remained unclear. This study shows that S. lugdunensis, a commensal bacterium that shares the nasal niche with S. aureus and is associated with a reduced S. aureus carriage rate in humans, produces a novel cyclic peptide antibiotic (lugdunin) that inhibits colonization by S. aureus in animal models. Lugdunin is bactericidal against major pathogens and not prone to causing development of resistance in S. aureus, suggesting that lugdunin or lugdunin-producing commensals could be valuable for preventing staphylococcal infections.

631 citations