Isolation of a Novel Polyketide from Neodidymelliopsis sp.

Melissa M. Cadelis; Hugo Gordon; Alex Grey; Soeren Geese; Daniel R. Mulholland; Bevan S. Weir; Brent R. Copp; Siouxsie Wiles

doi:10.3390/molecules26113235

Isolation of a Novel Polyketide from Neodidymelliopsis sp.

Molecules ◽

10.3390/molecules26113235 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3235

Author(s):

Melissa M. Cadelis ◽

Hugo Gordon ◽

Alex Grey ◽

Soeren Geese ◽

Daniel R. Mulholland ◽

...

Keyword(s):

Antimicrobial Activity ◽

Natural Products ◽

Ambient Temperature ◽

Crude Extract ◽

Structure Elucidation ◽

Fungal Pathogens ◽

Spectroscopic Techniques ◽

Bioactive Natural Products

Fungi have become an invaluable source of bioactive natural products, with more than 5 million species of fungi spanning the globe. Fractionation of crude extract of Neodidymelliopsis sp., led to the isolation of a novel polyketide, (2Z)-cillifuranone (1) and five previously reported natural products, (2E)-cillifuranone (2), taiwapyrone (3), xylariolide D (4), pachybasin (5), and N-(5-hydroxypentyl)acetamide (6). It was discovered that (2Z)-cillifuranone (1) was particularly sensitive to ambient temperature and light resulting in isomerisation to (2E)-cillifuranone (2). Structure elucidation of all the natural products were conducted by NMR spectroscopic techniques. The antimicrobial activity of 2, 3, and 5 were evaluated against a variety of bacterial and fungal pathogens. A sodium [1-13C] acetate labelling study was conducted on Neodidymelliopsis sp. and confirmed that pachybasin is biosynthesised through the acetate polyketide pathway.

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Antimicrobial Metabolites against Methicillin-Resistant Staphylococcus aureus from the Endophytic Fungus Neofusicoccum australe

Molecules ◽

10.3390/molecules26041094 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1094

Author(s):

Melissa M. Cadelis ◽

Soeren Geese ◽

Benedict B. Uy ◽

Daniel R. Mulholland ◽

Shara J. van de Pas ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Antimicrobial Activity ◽

Natural Products ◽

Structure Elucidation ◽

Methicillin Resistant Staphylococcus Aureus ◽

Inhibitory Concentration ◽

Spectroscopic Methods ◽

Methicillin Resistant ◽

Bioassay Guided Fractionation ◽

Antimicrobial Metabolites

Antimicrobial bioassay-guided fractionation of the endophytic fungi Neofusicoccum australe led to the isolation of a new unsymmetrical naphthoquinone dimer, neofusnaphthoquinone B (1), along with four known natural products (2–5). Structure elucidation was conducted by nuclear magnetic resonance (NMR) spectroscopic methods, and the antimicrobial activity of all the natural products was investigated, revealing 1 to be moderately active towards methicillin-resistant Staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 16 µg/mL.

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New and bioactive natural products from an endophyte of Panax notoginseng

RSC Advances ◽

10.1039/c7ra07060h ◽

2017 ◽

Vol 7 (60) ◽

pp. 38100-38109 ◽

Cited By ~ 12

Author(s):

Jun Xie ◽

Ying-Ying Wu ◽

Tian-Yuan Zhang ◽

Meng-Yue Zhang ◽

Wei-Wei Zhu ◽

...

Keyword(s):

Antimicrobial Activity ◽

Natural Products ◽

Secondary Metabolites ◽

Antiviral Activity ◽

Cytotoxic Activity ◽

Endophytic Fungi ◽

Panax Notoginseng ◽

Bioactive Natural Products

Secondary metabolites with cytotoxic activity, antiviral activity and antimicrobial activity from the endophytic fungi of Panax notoginseng.

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Direct Stereospecific Synthesis of Unprotected N-H and N-Me Aziridines from Olefins

Science ◽

10.1126/science.1245727 ◽

2014 ◽

Vol 343 (6166) ◽

pp. 61-65 ◽

Cited By ~ 157

Author(s):

Jawahar L. Jat ◽

Mahesh P. Paudyal ◽

Hongyin Gao ◽

Qing-Long Xu ◽

Muhammed Yousufuddin ◽

...

Keyword(s):

Natural Products ◽

Ambient Temperature ◽

Building Block ◽

Direct Synthesis ◽

Stereospecific Synthesis ◽

Quantum Mechanical ◽

Quantum Mechanical Calculations ◽

One Pot ◽

Rhodium Catalysis ◽

Bioactive Natural Products

Despite the prevalence of the N-H aziridine motif in bioactive natural products and the clear advantages of this unprotected parent structure over N-protected derivatives as a synthetic building block, no practical methods have emerged for direct synthesis of this compound class from unfunctionalized olefins. Here, we present a mild, versatile method for the direct stereospecific conversion of structurally diverse mono-, di-, tri-, and tetrasubstituted olefins to N-H aziridines usingO-(2,4-dinitrophenyl)hydroxylamine (DPH) via homogeneous rhodium catalysis with no external oxidants. This method is operationally simple (i.e., one-pot), scalable, and fast at ambient temperature, furnishing N-H aziridines in good-to-excellent yields. Likewise, N-alkyl aziridines are prepared from N-alkylated DPH derivatives. Quantum-mechanical calculations suggest a plausible Rh-nitrene pathway.

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Wood-decaying fungi found in Ghana: A rich source of new anti-infective compounds

AAS Open Research ◽

10.12688/aasopenres.12957.1 ◽

2019 ◽

Vol 2 ◽

pp. 20

Author(s):

Samuel Yaw Aboagye ◽

Vincent Amarh ◽

Paul A. Lartey ◽

Patrick Kobina Arthur

Keyword(s):

Antimicrobial Activity ◽

Natural Products ◽

Drug Discovery ◽

Bacterial Infections ◽

Antimicrobial Agents ◽

Significant Proportion ◽

Microbial Pathogens ◽

Antimicrobial Compounds ◽

Bioactive Natural Products ◽

Test Organisms

Background: Discovery of bioactive natural products are instrumental for development of novel antibiotics. The discovery and development of natural products such as penicillin represented a major milestone in the treatment of bacterial infections. Currently, many antibiotics have lost their relevance in clinics due to the emergence of drug-resistant microbial pathogens. Hence, there is the need for continuous search of new compounds endowed with potent antimicrobial activity. Methods: In this study, wood-decaying fungi (WDF) from Ghana were explored for their potential as sources of novel antimicrobial compounds with intent of expanding the effort into a drug discovery programme in the near future. Extracts from cultures of 54 morphologically distinct WDF isolates were analyzed for the presence of antimicrobial agents. Results: The extracts from 40 out of the 54 WDF isolates exhibited significant antimicrobial activity against either Staphylococcus aureus, Escherichia coli or Candida albicans. Fractionation of these bioactive extracts, followed by bioassay of the organic fractions obtained, indicate that extracts exhibiting antimicrobial activity against more than one of the three test organisms could be attributed to the presence of different bioactive compounds. Analysis of the composition of the extracts revealed that terpenes were predominant. Conclusions: This study suggests that a significant proportion of WDF in Ghana produce antimicrobial compounds which could be potential sources of novel anti-infective agents and support the plans of developing a drug discovery programme in Ghana based on the fermentation of WDF.

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Bioactive natural products as a potential source of new pharmacophores. A theory of memory

Pure and Applied Chemistry ◽

10.1351/pac200173030555 ◽

2001 ◽

Vol 73 (3) ◽

pp. 555-560 ◽

Cited By ~ 73

Author(s):

◽

M. Iqbal Choudhary

Keyword(s):

Natural Products ◽

Hydrogen Bonding ◽

Bioactive Compounds ◽

Structure Elucidation ◽

Memory Storage ◽

Bioactive Natural Products ◽

Potential Source ◽

Glucosidase Inhibitors ◽

Bioassay Guided Fractionation ◽

The Brain

The plant kingdom offers a rich source of structural biodiversity in the form of a variety of natural products. Our work on new bioactive compounds from medicinal plants has led to the isolation and structure elucidation of a number of exciting new pharmacophores. Bioassay-guided fractionation has recently led to the discovery of a series of new acetylcholinesterase, urease and a-glucosidase inhibitors, antioxidants and other classes of bioactive compounds, which will be presented. A theory based on hydrogen bonding on the chemical basis of memory storage in the brain is presented.

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Isolation, Structure Elucidation and Anti-microbial potential of a New Sphingolipid from Salvadora oleoides

Journal of the chemical society of pakistan ◽

10.52568/000787/jcsp/41.05.2019 ◽

2019 ◽

Vol 41 (5) ◽

pp. 917-917

Author(s):

Hafiza Naila Khalid Hafiza Naila Khalid ◽

Ejaz Ahmed Ejaz Ahmed ◽

Ahsan Sharif Ahsan Sharif ◽

Sumra Amanat Sumra Amanat ◽

Faiza Arshed Faiza Arshed ◽

...

Keyword(s):

Antimicrobial Activity ◽

Ethyl Acetate ◽

Chemical Reactions ◽

Structure Elucidation ◽

Soluble Fraction ◽

2D Nmr ◽

Spectroscopic Techniques ◽

Whole Plant ◽

Microbial Potential

Salvadoramide (1) have been isolated from the ethyl acetate soluble fraction of the whole plant of Salvadora oleoides. The structure, (2R)-2-hydroxy-N-[(2S, 3S, 4R, 5E, 7E)-1, 3, 4-trihydroxy-5, 7-tetra decdiene-2-yl] tetradecanamide), was established by the use of sophisticated modern spectroscopic techniques (1D and 2D-NMR, EIMS, HREIMS, UV and IR) and chemical reactions. The compound was further evaluated for its antimicrobial activity.

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Antimicrobial Activity of the Leaf, Flower and Stem Extracts of Sphenoclea zeylanica

International Journal of Applied Sciences and Biotechnology ◽

10.3126/ijasbt.v4i3.15760 ◽

2016 ◽

Vol 4 (3) ◽

pp. 325-329 ◽

Cited By ~ 1

Author(s):

J. Gowri ◽

P.Arockia Sahayaraj ◽

M Amaladasan

Keyword(s):

Antimicrobial Activity ◽

Natural Products ◽

Secondary Metabolites ◽

Microbial Activity ◽

Leaf Extract ◽

Microbial Growth ◽

Zone Of Inhibition ◽

Bioactive Natural Products ◽

Antibacterial And Antifungal Activities ◽

Antibacterial And Antifungal

The present study was carried out with an objective to investigate the antimicrobial potentials of leaves, flowers and stem extracts of Sphenoclea zeylanica. The aim of the study was to evaluate the antimicrobial activity and to determine the zone of inhibition of extracts against medically important bacterial and fungal strains. The antimicrobial activity was determined in the extracts using zone of inhibition method. The antibacterial and antifungal activities of extracts (40, 50, 60 and 70) of Sphenoclea zeylanica were tested against B. subtilis, P. vulgaris, S.aureus, E.coli, C. albicans, A. niger, S. typhi and B. cereus. Zone of inhibition of extracts were compared with that of control for antimicrobial activity. The results showed that the leaf extract showed notable inhibition of the microbial growth against the tested organisms. The microbial activity of the Sphenoclea zeylanic a might be due to the presence of various secondary metabolites. Hence, this plant can be used to identify the specific bioactive natural products which may serve as leads in the development of new antimicrobial agents.Int J Appl Sci Biotechnol, Vol 4(3): 325-329

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