High resolution Fourier transform mass spectrometry (HRFTMS) and nuclear magnetic resonance (NMR) spectroscopy were employed as complementary metabolomic tools to dereplicate the chemical profile of the new and antitrypanosomally active sponge-associated bacterium Actinokineospora sp. EG49 extract. Principal Component (PCA), hierarchical clustering (HCA), and orthogonal partial least square-discriminant analysis (OPLS-DA) were used to evaluate the HRFTMS and NMR data of crude extracts from four different fermentation approaches. Statistical analysis identified the best culture one-strain-many-compounds (OSMAC) condition and extraction procedure, which was used for the isolation of novel bioactive metabolites. As a result, two new O-glycosylated angucyclines, named actinosporins A (1) and B (2), were isolated from the broth culture of Actinokineospora sp. strain EG49, which was cultivated from the Red Sea sponge Spheciospongia vagabunda. The structures of actinosporins A and B were determined by 1D- and 2D-NMR techniques, as well as high resolution tandem mass spectrometry. Testing for antiparasitic properties showed that actinosporin A exhibited activity against Trypanosoma brucei brucei with an IC50 value of 15 µM; however no activity was detected against Leishmania major and Plasmodium falciparum, therefore suggesting its selectivity against the parasite Trypanosoma brucei brucei; the causative agent of sleeping sickness.

Marine invertebrate-associated symbiotic bacteria produce a plethora of novel secondary metabolites which may be structurally unique with interesting pharmacological properties. Selection of strains usually relies on literature searching, genetic screening and bioactivity results, often without considering the chemical novelty and abundance of secondary metabolites being produced by the microorganism until the time-consuming bioassay-guided isolation stages. To fast track the selection process, metabolomic tools were used to aid strain selection by investigating differences in the chemical profiles of 77 bacterial extracts isolated from cold water marine invertebrates from Orkney, Scotland using liquid chromatography-high resolution mass spectrometry (LC-HRMS) and nuclear magnetic resonance (NMR) spectroscopy. Following mass spectrometric analysis and dereplication using an Excel macro developed in-house, principal component analysis (PCA) was employed to differentiate the bacterial strains based on their chemical profiles. NMR 1H and correlation spectroscopy (COSY) were also employed to obtain a chemical fingerprint of each bacterial strain and to confirm the presence of functional groups and spin systems. These results were then combined with taxonomic identification and bioassay screening data to identify three bacterial strains, namely Bacillus sp. 4117, Rhodococcus sp. ZS402 and Vibrio splendidus strain LGP32, to prioritize for scale-up based on their chemically interesting secondary metabolomes, established through dereplication and interesting bioactivities, determined from bioassay screening.

Metabolomic methods can be utilized to screen diverse biological sources of potentially novel and sustainable sources of antibiotics and pharmacologically-active drugs. Dereplication studies by high resolution Fourier transform mass spectrometry coupled to liquid chromatography (LC-HRFTMS) and nuclear magnetic resonance (NMR) spectroscopy can establish the chemical profile of endophytic and/or endozoic microbial extracts and their plant or animal sources. Identifying the compounds of interest at an early stage will aid in the isolation of the bioactive components. Therefore metabolite profiling is important for functional genomics and in the search for new pharmacologically active compounds. Using the tools of metabolomics through the employment of LC-HRFTMS as well as high resolution NMR will be a very efficient approach. Metabolomic profiling has found its application in screening extracts of macroorganisms as well as in the isolation and cultivation of suspected microbial producers of bioactive natural products.Metabolomics is being applied to identify and biotechnologically optimize the production of pharmacologically active secondary metabolites. The links between metabolome evolution during optimization and processing factors can be identified through metabolomics. Information obtained from a metabolomics dataset can efficiently establish cultivation and production processes at a small scale which will be finally scaled up to a fermenter system, while maintaining or enhancing synthesis of the desired compounds. MZmine (BMC Bioinformatics 11:395-399, 2010; http://mzmine.sourceforge.net/download.shtml ) and SIEVE ( http://www.vastscientific.com/resources/index.html ; Rapid Commun Mass Spectrom 22:1912-1918, 2008) softwares are utilized to perform differential analysis of sample populations to find significant expressed features of complex biomarkers between parameter variables. Metabolomes are identified with the aid of existing high resolution MS and NMR records from online or in-house databases like AntiMarin, a merger database of Antibase (Laatsch H. Antibase Version 4.0 - The Natural Compound Identifier. Wiley-VCH Verlag GmbH & Co. KGaA, 2012) for microbial secondary metabolites as well as higher fungi and MarinLit for marine natural products (Blunt J. MarinLit. University of Canterbury, New Zealand, 2012). This is further validated through available reference standards and NMR experiments. Metabolomics has become a powerful tool in systems biology which allows us to gain insights into the potential of natural isolates for synthesis of significant quantities of promising new agents and allows us to manipulate the environment within fermentation systems in a rational manner to select a desired metabolome.

Metabolomics and genomics are two complementary platforms for analyzing an organism as they provide information on the phenotype and genotype, respectively. These two techniques were applied in the dereplication and identification of bioactive compounds from a Streptomyces sp. (SM8) isolated from the sponge Haliclona simulans from Irish waters. Streptomyces strain SM8 extracts showed antibacterial and antifungal activity. NMR analysis of the active fractions proved that hydroxylated saturated fatty acids were the major components present in the antibacterial fractions. Antimycin compounds were initially putatively identified in the antifungal fractions using LC-Orbitrap. Their presence was later confirmed by comparison to a standard. Genomic analysis of Streptomyces sp. SM8 revealed the presence of multiple secondary metabolism gene clusters, including a gene cluster for the biosynthesis of the antifungal antimycin family of compounds. The antimycin gene cluster of Streptomyces sp. SM8 was inactivated by disruption of the antimycin biosynthesis gene antC. Extracts from this mutant strain showed loss of antimycin production and significantly less antifungal activity than the wild-type strain. Three butenolides, 4,10-dihydroxy-10-methyl-dodec-2-en-1,4-olide (1), 4,11-dihydroxy-10-methyl-dodec-2-en-1,4-olide (2), and 4-hydroxy-10-methyl-11-oxo-dodec-2-en-1,4-olide (3) that had previously been reported from marine Streptomyces species were also isolated from SM8. Comparison of the extracts of Streptomyces strain SM8 and its host sponge, H. simulans, using LC-Orbitrap revealed the presence of metabolites common to both extracts, providing direct evidence linking sponge metabolites to a specific microbial symbiont.

This version is available at https://strathprints.strath.ac.uk/59826/ Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Please check the manuscript for details of any other licences that may have been applied. You may not engage in further distribution of the material for any profitmaking activities or any commercial gain. You may freely distribute both the url (https://strathprints.strath.ac.uk/) and the content of this paper for research or private study, educational, or not-for-profit purposes without prior permission or charge.Any correspondence concerning this service should be sent to the Strathprints administrator: strathprints@strath.ac.ukThe Strathprints institutional repository (https://strathprints.strath.ac.uk) is a digital archive of University of Strathclyde research outputs. It has been developed to disseminate open access research outputs, expose data about those outputs, and enable the management and persistent access to Strathclyde's intellectual output. mellein. Cladospirone B and desmethyl-lasiodiplodin were among the predictive compounds generated by the S-plot, and these compounds exhibited good activity against Trypanosoma brucei brucei with MICs of 17.8 µM and 22.5 µM, respectively.Therefore, HR-LCMS and NMR-based metabolomics proved to be a powerful decisionmaking tool in mining active metabolites of L. theobromae against T. b. brucei.3

Endophytic fungi associated with medicinal plants are a potential source of novel chemistry and biology that may find applications as pharmaceutical and agrochemical drugs. In this study, a combination of metabolomics and bioactivity-guided approaches were employed to isolate secondary metabolites with cytotoxicity against cancer cells from an endophytic Aspergillus aculeatus. The endophyte was isolated from the Egyptian medicinal plant Terminalia laxiflora and identified using molecular biological methods. Metabolomics and dereplication studies were accomplished by utilizing the MZmine software coupled with the universal Dictionary of Natural Products database. Metabolic profiling, with aid of multivariate data analysis, was performed at different stages of the growth curve to choose the optimized method suitable for up-scaling. The optimized culture method yielded a crude extract abundant with biologically-active secondary metabolites. Crude extracts were fractionated using different high-throughput chromatographic techniques. Purified compounds were identified by HR-ESI-MS, 1D- and 2D-NMR. This study introduced a new method of dereplication utilizing both high-resolution mass spectrometry and NMR spectroscopy. The metabolites were putatively identified by applying a chemotaxonomic filter. We also present a short review on the diverse chemistry of terrestrial endophytic strains of Aspergillus, which has become a part of our dereplication work and this will be of wide interest to those working in this field.

The marine sponge Haliclona simulans collected from the Irish Sea yielded two new steroids: 24-vinyl-cholest-9-ene-3β,24-diol and 20-methyl-pregn-6-en-3β-ol,5α,8α-epidioxy, along with the widely distributed 24-methylenecholesterol. One of the steroids possesses an unusually short hydrocarbon side chain. The structures were elucidated using nuclear magnetic resonance spectroscopy and confirmed using electron impact- and high resolution electrospray-mass spectrometry. All three steroids possess antitrypanosomal and anti-mycobacterial activity. All the steroids were found to possess low cytotoxicity against Hs27 which was above their detected antitrypanosomal potent concentrations.

Background: The leaves of Alchornea laxiflora are traditionally used in the south of Nigeria to prevent preterm births. Aim: This study was designed to investigate the activity of A. laxiflora on uterine contractility. Setting: The leaves of the plant were collected from forests in Egor, Benin City, Nigeria. Methods: The leaves were cleaned and extracted in methanol. The extract (0.005 mg/mL–3.5 mg/mL) was tested on spontaneous uterine contraction and on oxytocin-induced contraction in normal and Ca2+-free media. The plant extract (0.0035 mg/mL, 0.035 mg/mL, 0.35 mg/mL and 3.5 mg/mL) was tested on high KCl-induced uterine contractions (80 mM). The plant extract (3.5 mg/mL) was also studied in the presence of amiodarone and glibenclamide in separate experiments. Mass spectrometric analysis was additionally performed on the plant extract in order to identify significant secondary metabolites that may have contributed to the activity of the plant. Results: The plant extract inhibited spontaneous, oxytocin and high KCl-induced uterine contractions and also significantly inhibited (p < 0.01) oxytocin-induced uterine contraction in Ca2+-free medium. The plant extract significantly inhibited (p < 0.01 and p < 0.05) oxytocin’s amplitude in the presence of amiodarone and glibenclamide, respectively. Secondary metabolites belonging to classes of fatty acids, glycols, terpenes, flavonoid glycosides and porphyrins were identified. Conclusion: Alchornea laxiflora inhibited mouse uterine contractility possibly through interaction with potassium and calcium channels. Of the known metabolites identified, 3-deoxy-arabino-hept-2-ulosonic acid, 17-hydroxyingenol and phaeophorbide-a methyl inhibit uterine contractility and may contribute to the activity of A. laxiflora in utero.