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This work was performed to dig into the phytochemical composition and bioactivities of Nocardiopsis sp. UR67 associated with the marine sponge Callyspongia sp. It was fermented in suspension and immobilised in calcium alginate bead cultures. The ethyl acetate extracts, afforded from the broth in each case named EG-49 and J-48g, respectively, revealed 16 chemical principles mostly belonging to polyketides, macrolides, and peptides. EG-49 and J-48g displayed anti-Candida albicans activity with IC50 values of 8.1 and 8.3 µg/mL, and a substantial cytotoxic effect against lung adenocarcinoma H1650 at IC50 12.6 and 13.7 µg/mL, respectively. However, only EG-49 exhibited a noteworthy anti-trypanosomal activity at 7.5 µg/mL. Molecular docking of the characterised compounds against Trypanosoma brucei trypanothione reductase demonstrated the highest binding models of griseochelin-methyl ester (9) and filipin-II (11), which drew considerable significance of the metabolites derived from Nocardiopsis sp. UR67 developing potential T. brucei trypanothione reductase inhibitors. [ABSTRACT FROM AUTHOR]

In this work, three fungal endophytes identified as Aspergillus terreus (AFL, AFSt and AFR), were studied for their antioxidant potential. LC-MS-based metabolomics, followed by multivariate statistical analysis were then applied to comprehensively profile their extracts. The three fungal endophytes revealed interesting antioxidant potential, in particular, the strain isolated from the Artemisia annua leaves (AFL), which was rich in different types of phenolic metabolites. Additionally, all fungal-derived ethyl acetate extracts showed potent inhibition against the prooxidant xanthine oxidase. Multivariate analysis (PCA and PLS-DA) demonstrated a unique chemical fingerprint for each strain, where phenolics, coumarins, and polyketides were the discriminative metabolites of the three fungal strains. The present findings highlighted the power of metabolomics in the chemotaxonomical classification of closely related strains. It also asserted the role of fungal endophytes in the management of oxidative stress, particularly when they are utilized in the production of fermented food products. [ABSTRACT FROM AUTHOR]

Depression is a common mental disturbance that can be categorized as mild, moderate or severe. Mesemberine alkaloids, the main recognized phytoconstituents of some plants belonging to family Mesembryanthemaceae, are well-known as serotonin reuptake inhibitors. Therefore, the objective of this study is to evaluate the antidepressant activity of the alkaloidal fraction of Mesembryanthemum cordifolium L.f. (Aptenia cordifolia) roots, family Mesembryanthemaceae using forced swimming test, assisted by metabolomic analysis and in silico ligand-based and structure-based screening. Results showed that the alkaloidal fraction displayed an antidepressant activity superior to imipramine hydrochloride, a standard antidepressant agent. Nine alkaloids were annotated from the metabolomic analysis. Interestingly, among the dereplicated constituents, mesembrane (5) displayed strong binding affinity to SERT protein, which is slightly higher than the antidepressant drug venlafaxine. In conclusion, the alkaloidal fraction of the M. cordifolium (A. cordifolia) root exhibits an antidepressant activity which can be attributed in part to mesembrane (5). [ABSTRACT FROM AUTHOR]

Both ethyl acetate and aqueous fractions of Tabebuia aurea leaves exhibited noteworthy antioxidant and nephroprotective activities against carbon tetrachloride (CCl4)-induced nephrotoxicity in rats, as evidenced by the remarkable improvements of renal serum biomarkers and histopathological features. Additionally, the ethyl acetate fraction displayed a prominent in vitro antitrypanosomal activity against Trypanosoma brucei; consequently, the leaves were subjected to LC-HR-ESI-MS metabolomic profiling to discover the constituents that possibly underlie their bioactivities. Therefore, ten metabolites were characterized, mostly dominated by flavonoids. Interestingly, two identified constituents viz., 3,9,12,15-octadecatetraenoic acid (9) and 9,11,13-octadecatrienoic acid (10) are reported firstly herein from the genus Tabebuia. Furthermore, among the dereplicated constituents, rutin (5) and kaempferol 3-O-rutinoside (6) exhibited the highest docking scores as effective antitrypanosomal compounds. [ABSTRACT FROM AUTHOR]

Fungal endophytes are a major source of anti-infective agents and other medically relevant compounds. However, their classical blinded-chemical investigation is a challenging process due to their highly complex chemical makeup. Thus, utilizing cheminformatics tools such as metabolomics and computer-aided modelling is of great help deal with such complexity and select the most probable bioactive candidates. In the present study, we have explored the fungal endophytes associated with the well-known antimalarial medicinal plant Artemisia annua for their production of further antimalarial agents. Based on the preliminary antimalarial screening of these endophytes and using LC-HRMS-based metabolomics and multivariate analyses, we suggested different potentially active metabolites (compounds 1–8). Further in silico investigation using the neural-network-based prediction software PASS led to the selection of a group of quinone derivatives (compounds 1–5) as the most possible active hits. Subsequent in vitro validation revealed emodin (1) and physcion (2) to be potent antimalarial candidates with IC50 values of 0.9 and 1.9 µM, respectively. Our approach in the present investigation therefore can be applied as a preliminary evaluation step in the natural products drug discovery, which in turn can facilitate the isolation of selected metabolites notably the biologically active ones. [ABSTRACT FROM AUTHOR]

• Six endophytic fungi isolated from medicago sativa were studied for their antimicrobial activity and their ability for production of extracellular oxidative enzymes. • Aspergillus ochraceus MSEF6 displayed the most remarkable inhibitory potentials using potato dextrose broth liquid culture medium. • Chemical profiling for the PDB culture of A. ochraceus MSEF6, using LC-HR-ESI-MS, was accessed. • Various metabolites with reported antimicrobial activities were characterized. • Almost all isolates could be considered as peroxidase producers, while only the A. ochraceus MSEF 6 showed considerable laccase activity. Six endophytic fungi were isolated from the healthy roots, stems, and leaves of alfalfa (Medicago sativa L.), usually renowned as "father of all foods". The isolated fungi were cultured on agar dual plates to investigate their antimicrobial potential against five pathogenic fungi, namely Candida albicans, Aspergillus flavus, Fusarium oxysporum, Fusarium solani, and Fusarium sp., and two pathogenic bacteria; Bacillus cereus and Serratia marcescens. Out of the isolated fungi, only Aspergillus ochraceus MSEF6 inhibited the growth of all the tested micro-organisms except S. marcescens. Therefore, such strain was cultured using OSMAC (one strain many compounds) approach to find out the most convenient medium for production of its antimicrobial components, of which only potato dextrose broth (PDB) displayed remarkable antimicrobial activity with MICs values of 15–30 mg/mL. Accordingly, the recovered ethyl acetate extract of the potato dextrose broth (PDB) culture of A. ochraceus MSEF6 was subjected to chemical profiling using liquid chromatography-high resolution-mass spectroscopy (LC-HR-MS). A number of structurally diverse metabolites, mainly phenolics, quinones, benzofurans, and isochromanones, with reported antimicrobial properties were therefore characterized for the first time from A. ochraceus MSEF6. Moreover, the ability of the isolated fungi to produce extracellular oxidative enzymes was also screened, where most of them displayed important peroxidase activity, while the production of laccase enzyme was exclusively shown by A. ochraceus MSEF6. These results highlight the endophytic fungus, A. ochraceus MSEF6 as a promising supply of natural antimicrobial leads and microbial enzymes, which are of pharmaceutical and industrial importance. [ABSTRACT FROM AUTHOR]