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Liquid-liquid fractionation was performed for two samples of honey, and the fractions were nanoencapsulated in microemulsions using the method of water dilution. The microemulsions were characterized for particle size, zeta potential, polydispersity, and physicochemical stability under refrigeration conditions. The antiproliferative activity of extracts and their microemulsions was tested on HepG2 and MCF-7 cancer cells (liver and breast cancer cell lines, respectively). Results revealed successful preparation of the honey-loaded microemulsions with suitable particle sizes within 14 – 16 nm, homogenous dispersion with polydispersity index (PDI) ranging within 0.13 – 0.34, and neutral surface charge. Microemulsions displayed insignificant changes in their physicochemical properties after storage for 3 months. The nanoencapsulation of honey in microemulsion formulations led to significant decrease in the IC50 values (or up to 104 times increase in antiproliferative potency). Therefore it can be concluded that nanoencapsulation of honey extracts significantly potentiates their antiproliferative activity, thus presenting a possible powerful tool for cancer treatment.

Chromatographic analysis of a crude ethyl acetate (EtOAc) extract derived from a solid rice culture incubated at 40°C to mimic the natural ecological niche of the extremophilic fungus Botryotrichum piluliferum strain WESH19 yielded a new natural butenolide compound (1) together with three known metabolites (2–4). Chemical structures of the isolated metabolites were confirmed by HR-ESI-MS along with 1D and 2D NMR spectroscopic analyses. Compounds 1–3 revealed pronounced antimicrobial activities against Staphylococcus aureus (ATCC 700699), Enterococcus faecalis (ATCC 29212), and Enterococcus faecium (ATCC 35667), while their antifungal activities were assessed against the extremophilic fungus Penicillium simplicissimum strain WSH17 (GenBank Acc. No. MN055685). This study adds another example of how extreme environmental conditions may influence secondary metabolism of the inhabiting fungi.

Endophytic fungi including black aspergilli have the potential to synthesize multiple bioactive secondary metabolites. Therefore, the search for active metabolites from endophytic fungi against pathogenic microbes has become a necessity for alternative and promising strategies. In this study, 25 endophytic fungal isolates associated with Malusdomestica were isolated, grown, and fermented on a solid rice medium. Subsequently, their ethyl acetate crude extracts were pretested for biological activity. One endophytic fungal isolate demonstrated the highest activity and was chosen for further investigation. Based on its phenotypic, ITS ribosomal gene sequences, and phylogenetic characterization, this isolate was identified as Aspergillus tubingensis strain AN103 with the accession number (KR184138). Chemical investigations of its fermented cultures yielded four compounds: Pyranonigrin A (1), Fonsecin (2), TMC 256 A1 (3), and Asperazine (4). Furthermore, 1H-NMR, HPLC, and LC-MS were performed for the identification and structure elucidation of these metabolites. The isolated pure compounds showed moderate-to-potent antibacterial activities against Pseudomonas aeruginosa and Escherichiacoli (MIC value ranged from 31 and 121 to 14.5 and 58.3 μg/mL), respectively; in addition, the time–kill kinetics for the highly sensitive bacteria against isolated compounds was also investigated. The antifungal activity results show that (3) and (4) had the maximum effect against Fusarium solani and A. niger with inhibition zones of 16.40 ± 0.55 and 16.20 ± 0.20 mm, respectively, and (2) had the best effect against Candida albicans, with an inhibition zone of 17.8 ± 1.35 mm. Moreover, in a cytotoxicity assay against mouse lymphoma cell line L5178Y, (4) exhibited moderate cytotoxicity (49% inhibition), whereas (1–3) reported weak cytotoxicity (15, 26, and 19% inhibition), respectively. Our results reveal that these compounds might be useful to develop potential cytotoxic and antimicrobial drugs and an alternative source for various medical and pharmaceutical fields.

Endophytic fungi including black aspergilli have the potential to synthesize multiple bioactive secondary metabolites. Therefore, the search for active metabolites from endophytic fungi against pathogenic microbes has become a necessity for alternative and promising strategies. In this study, 25 endophytic fungal isolates associated with

Fine chromatographic fractionation of the EtOAc (ethyl acetate) extract of a solid rice culture of the endophytic fungus Aspergillus versicolor strain Eich.5.2.2 from the petals of flowers of the Egyptian water hyacinth Eichhornia crassipes revealed the isolation of a new quinolone derivative (1) along with its known isomer aniduquinolone A (2). Structure elucidation of the isolated compounds was unambiguously determined through HRESIMS (High-Resolution Electrospray Ionization Mass Spectrometry) and extensive 1D and 2D NMR (Nuclear Magnetic Resonance) spectroscopy. The relative and absolute configurations of the new compound are deduced through ROESY (Rotational Overhauser Effect SpectroscopY), optical rotation as well as biogenetic consideration. Interestingly, the epimers (1/2) altogether exhibited a significant antibacterial activity against the bacterium Staphylococcus aureus (ATCC700699) with a MIC (Minimum Inhibitory Concentration) of 0.4 µg/mL and fortunately with no cytotoxic effects highlighting a specificity of the antibacterial effect.

Chemical exploration of mangrove-rhizosphere-associated fungus Emericella sp. strain SWR1718 (Aspergillaceae) was performed through various chromatographic workup procedures. The achieved results afforded one new natural compound, emericelactone E (1) in addition to known compounds (2–7). The planar structures of the purified compounds were unambiguously carried out using several spectroscopic methods. Both relative and absolute configurations of compound 1 were carefully determined based on NOESY experiments, coupling constants and comparing its optical rotation with related congeners. Moreover, a plausible biosynthetic pathway of 1 and its related derivatives is reported for the first time in our study. The cytotoxic potential of isolated metabolites was assessed toward three human tumor cell lines where some of them exhibited moderate activities compared to paclitaxel as a standard anticancer.

Co-cultivation of viable cells of the human pathogenic bacterium Pseudomonas aeruginosa with the endophytic fungus Fusarium tricinctum induced silent bacterial biosynthetic gene clusters. Visual and chemical inspection of the co-cultures by comparison with the axenic cultures showed a clear reaction of P. aeruginosa towards its fungal competitor which was reflected by the deep greenish coloration of the co-cultures. Inspection of the HPLC chromatograms of the co-cultures revealed the induction of the pseudomonal quorum sensing molecule 2-heptyl-4-hydroxy-quinolone (HHQ) along with the antifungal phenazine alkaloids, phenazine-1-carboxylic acid (PCA) and phenazine-1-carboxamide (PCN), which are well-known metabolites of P. aeruginosa. The latter compounds were not detected in axenic bacterial cultures. In contrast to P. aeruginosa, no metabolic responses were detected for F. tricinctum which is in sharp contrast to previous co-culture experiments with this fungus using other bacteria.

Chromatographic refining of the EtOAc extract of a solid rice culture of the hypersaline lake-derived fungus Penicillium simplicissimum strain WSH17 afforded a new linear antibacterial peptide quinoisobutyride A (1) along with three known metabolites (2-4). The chemical structure of 1 was unambiguously determined based on extensive 1D and 2D NMR spectroscopic analyses together with HRESIMS. In addition, Marfey’s derivatization method along with biogenetic considerations were used to determine the absolute configuration of its amino acids’ entities. Interestingly, in this study we distinguished a new unusual heterocyclic amino acid which is comprised as a unit of compound 1. Among the isolated compounds, only 1 revealed a promising antibacterial activity against Staphylococcus aureus (ATCC700699) with a MIC value of 2.72 μM (2.0 μg/mL). Moreover, citrinamide A (3) was the only isolated compound that showed a cytotoxic activity against human epithelial colorectal adenocarcinoma (Caco-2) cell line with an IC50 value of 12.76 μM (5.5 μg/mL).

The Alternaria species are considered to produce a plethora of several mycotoxins constituting a risk factor for both human and animal health. This work aimed mainly to explore the cytotoxicity of a combined mixture of altenuene (ALT), alternariol (AOH), tenuazonic acid (TeA), and altenuisol (AS) toxins produced by pathogenic A. alternata toward human oral epithelial cells (PCS-200-014), lung fibroblast cells (WI-38), and male albino rats. The sequencing of the multi-locus, RNA polymerase second largest subunit (rpb2), glyceraldehyde-3-phosphate dehydrogenase (gapdh), and Alternaria major allergen gene (Alt a 1) was performed to infer relationships among isolated Alternaria species. The phylogenetic analysis of gapdh, rpb2, and Alt-a 1 sequence data indicated that all isolates resided in A. alternata. The pathogenic potentiality of A. alternata was investigated on tomato plants cv. super strain B under greenhouse conditions, and all isolates were pathogenic to tomato plants, with significant (p < 0.05) variations. The ability of A. alternata isolates to produce mycotoxins was also explored using high-performance liquid chromatography (HPLC). All tested isolates were able to produce at least one of the assessed mycotoxins—ALT, AOH, TeA, and AS—and ALT was reported as the dominant mycotoxin, produced by 80% of A. alternata isolates. The cytotoxic properties of the combined mixture of ALT, AOH, TeA, and AS at concentrations of 31.25, 62.50, 125, 250, and 500 µg/mL were assessed via the MTT assay method after exposure for 24 h versus the control. The treatment of both cell lines with combined mixtures of ALT, AOH, TeA, and AS showed a dose-dependent decrease in cell viability. The highest concentrations tested at 62.50, 125, 250, and 500 µg/mL significantly decreased cell viability and caused cell damage compared to the lowest concentration of 31.25 µg/mL and the control. The cytotoxicity and genotoxicity of the combined mixtures of ALT, AOH, TeA, and AS on male albino rats were also investigated via the gene expression of (TNF-α) and using hematological (CBC), chemical (alanine aminotransferase (ALT), aspartate aminotransferase (AST) and urea and creatinine), and histopathological analyses. A marked increase was observed in the levels of ALT, AST, urea and creatinine, TNF-α gene expression, red blood cells (RBCs), white blood cells (WBCs), hemoglobin (Hb), and packed cell volume % (PCV) after 28 days of exposure relative to the untreated control. Pathological alterations were also observed in the liver and kidney tissues of rats. Conclusively, this work provides a new understanding on the cytotoxicity and genotoxicity of mycotoxins of pathogenic A. alternata from tomatoes.

Chemical investigation of aerial parts of Helichrysum italicum yielded two new pyrone derivatives (1 and 2) along with ten known compounds. The structures of the new compounds were established by 1D and 2D NMR spectra as well as by HRESIMS data. Compound 1 represented a rare dimer of substituted α- and γ-pyrone units. DFT-NMR and TDDFT-ECD calculations were carried out to determine the absolute configuration of 1 but failed, representing the limitation of TDDFT-ECD calculation for the configurational assignment. All compounds were measured for their antibacterial and cytotoxic activity but proved to be inactive.

Chemical investigation of the mangrove-derived fungus Aspergillus sp. AV-2 following fermentation on solid rice medium led to the isolation of a new phenyl pyridazine derivative (1) and a new prenylated benzaldehyde derivative, dioxoauroglaucin (2), together with fourteen known compounds (3-16). Chemical structures of the new compounds were unambiguously determined based on HRESIMS and extensive 1D and 2D NMR spectroscopic analyses. Compounds 2-7, 8 and 13 were assessed for their antiproliferative activity against Caco-2 cell lines, where flavoglaucin (6) revealed the most potent cytotoxicity with IC50 of 2.87 μM.

A new cyclic pentapeptide, cotteslosin C (1), a new aflaquinolone, 22-epi-aflaquinolone B (3), and two new anthraquinones (9 and 10), along with thirty known compounds (2, 4 – 8, 11 – 34) were isolated from a co-culture of the sponge-associated fungus Aspergillus versicolor with Bacillus subtilis. The new metabolites were only detected in the co-culture extract, but not when the fungus was grown under axenic conditions. Furthermore, the co-culture extract exhibited an enhanced accumulation of the known constituents versicolorin B (14), averufin (16), and sterigmatocyctin (19) by factors of 1.5, 2.0, and 4.7, respectively, compared to the axenic fungal culture. The structures of the isolated compounds were elucidated on the basis of 1D and 2D NMR spectra and mass spectrometry as well as by comparison with literature data. The absolute configuration of compounds 3, 9, and 10 was determined by ECD (electronic circular dichroism) analysis aided by TDDFT-ECD (time-dependent density functional theory electronic circular dichroism) calculations. Compounds 15, 18 – 21, and 26 exhibited strong to moderate cytotoxic activity against the mouse lymphoma cell line L5178Y, with IC50 values ranging from 2.0 to 21.2 µM, while compounds 14, 16, 31, 32, and 33 displayed moderate inhibitory activities against several gram-positive bacteria, with MIC values ranging from 12.5 to 50 µM.

Phytochemical analysis of a crude ethyl acetate (EtOAc) extract derived from endophytic fungus Fusarium verticillioides strain WF18 afforded one new polyketide metabolite, fusaisocoumarin A (1), along with two known compounds, emodin (2) and sesquiterpenoid phytohormone (+)-abscisic acid (ABA) (3). Chemical structures of isolated compounds were elucidated based on HRESIMS together with 1Dand 2D-NMR spectroscopic analyses. Interestingly, all isolated compounds revealed pronounced antifungal activity against certain endophytic fungal strains namely; Aspergillus austroafricanus strain Eis.1, Aspergillus versicolor strain EIS2, Phoma fungicola strain AT100, Aspergillus tubingensis strain AN103 along with Candida albicans ATCC 90029 with MIC (minimum inhibitory concentration) range from 0.3 to 1.3 mu g/mL. the biosynthesis of anti fungal compounds and the phytohormone (+)-abscisic acid (ABA) illustrates an example of the crosstalks between the host plant and its endophyte in which the endophytic fungus produces metabolites defending the host plant against environmental stresses and also against other fungal phytopathogens. (C) 2020 SAAB. Published by Elsevier B.V. All rights reserved.

Two new cryptic 3,4-dihydronaphthalen-(2H)-1-one (1-tetralone) derivatives, aspvanicin A (1) and its epimer aspvanicin B (2), as well as several known cryptic metabolites (3–8), were obtained from the ethyl acetate extract of the co-culture of the endophytic fungus Aspergillus versicolor KU258497 with the bacterium Bacillus subtilis 168 trpC2 on solid rice medium. When A. versicolor was cultured axenically in liquid Wickerham medium supplemented with 3.5% DMSO, an additional three known secondary metabolites (9–11) were isolated that were lacking when the fungus was fermented on rice medium. The structures of the new compounds were elucidated using one- and two-dimensional NMR spectroscopy as well as HRESIMS. The relative and absolute configurations of 1 and 2 were determined by the combination of NMR and electronic circular dichroism (ECD) analysis aided by DFT conformational analysis and TDDFT-ECD calculations. The ECD calculations revealed that although the sign of the blue-shifted overlapping n-π∗ ECD transition follows the helicity rule of cyclic aryl ketones, the calculation of low-energy conformers and ECD spectra was necessary to determine the stereochemistry. All metabolites were assessed for their antibacterial and cytotoxic activities; one of the new diastereomers, compound 2, showed moderate cytotoxic activity against the mouse lymphoma cell line L5178Y.

Chemical investigation of a freshwater sediment-derived fungus, Penicillium sp. (S1a1), led to the isolation of three new tanzawaic acid derivatives, including penitanzchroman (1), tanzawaic acids Y (2) and Z (3), along with six known tanzawaic acid analogues (4-9), three known isochromans (10-12) and two known benzoquinones (13 and 14). The structures of the new compounds were established based on high-resolution mass spectrometry, and detailed analysis of one- and two-dimensional NMR spectroscopy. The relative configuration of the new compounds was assigned on the basis of NMR spectroscopic data including ROESY spectra. The absolute configuration was determined based on the specific optical rotation, in addition to biogenetic considerations in comparison with related co-isolated known metabolites. Penitanzchroman (1) constitutes a hitherto unprecedented skeleton, formed of tanzawaic acid A (5) and (3S)-6-hydroxy-8-methoxy-3,5-dimethylisochroman (10) linked by a C C bond. Moreover, all compounds were evaluated for their antibacterial and cytotoxic activities.

Ten new germacrane-type sesquiterpenoids (1–10) were isolated from a whole plant extract of Eupatorium chinense. The structures were elucidated by analysis of their NMR and MS data as well as by comparison with literature values. The absolute configuration of eupachinsin A (1) was determined by single-crystal X-ray diffraction analysis. Compounds 3 and 4 exhibited cytotoxicity against a human breast cancer cell line (MDA-MB-231), with IC50 values of 0.8 and 3.4 μM, respectively. In addition, compounds 3–5 showed cytotoxicity against the human hepatocellular carcinoma cell line (HepG2), with IC50 values ranging from 3.6 to 7.6 μM.

From the seeds of the traditional medicinal plant Ziziphus jujuba growing in Uzbekistan, the fungal endophyte Alternaria sp. was isolated. Extracts of this fungus grown on solid rice and liquid Wickerham culture media yielded 21 natural products. These natural products include the new phthalide natural product (±)7-methoxyphthalide-3-acetic acid (1) in addition to 20 known compounds including 19 polyketides and one alkaloid. Moreover, the OSMAC (One Strain MAny Compounds) approach is applied in this study. The unambiguous structure of the new compound was elucidated on the basis of one- and two-dimensional NMR spectroscopy in addition to HR-ESI-MS. Compounds 2, 3, 4, and 7 exhibited a cytotoxic activity against mouse lymphoma cell lines (L5178Y) with IC50 values of 1.7, 7.8, 6.8, and 6.2 μM, respectively when compared with the positive control kahalalide F (IC50 4.3 μM).

The mixed fermentation of the fungal endophyte Chaetomium sp. with an autoclaved culture of the bacterium Pseudomonas aeruginosa on solid rice medium led to an up to 33-fold increase in the accumulation of constitutively present fungal secondary metabolites (3–10), which included four new butenolide derivatives (3–5 and 7). In addition, two further shikimic acid analogues (1 and 2) were obtained from mixed cultures that were neither detected in axenic cultures of the fungus nor of the bacterium. Chaetoisochorismin (1) possesses an unusual (3-methoxycarbonylphenyl)pyruvate core structure. The structures of the new compounds were unequivocally elucidated by HRESIMS, one- and two-dimensional NMR analysis as well as by comparison with literature data. The absolute configurations of the structures of the new derivatives 1 and 2 were established by ECD calculations as well as by the modified Mosher's method. Compounds 1–3 and 5–7 were subjected to antimicrobial and cytotoxicity assays but were shown to be inactive.

Chemical investigation of the sponge derived fungus Arthrinium sp. following fermentation on solid rice medium led to the isolation of two new meroterpenoidal alcohols spiroarthrinols A (1) and B (2) together with eighteen known compounds (3-20). The structures and relative configuration of the new compounds were unambiguously determined based on HRESIMS and extensive 1D and 2D NMR spectroscopic analyses. In addition, a plausible biosynthetic pathway for the new compounds spiroarthrinols A (1) and B (2) was postulated encompassing a mixed polyketide/terpenoid pathway. When assessed for their antiproliferative activity against Caco-2 cell lines, none of the isolated compounds showed significant cytotoxicity.

Eight new hydroquinone derivatives, gliomastins A–D (1–4), 9-O-methylgliomastin C (5), acremonin A 1-O-β-D-glucopyranoside (6), gliomastin E 1-O-β-D-glucopyranoside (7), and 6′-O-acetyl-isohomoarbutin (8), together with seven known analogues were isolated from the marine-derived fungus Gliomastix sp. Their structures were elucidated by extensive spectroscopic analysis including 1D and 2D NMR measurements aided by DFT NMR calculations as well as MS data. TDDFT-ECD and OR calculations were performed to determine the absolute configurations of 1 and the aglycones of 6 and 7. Compound 1 features a novel skeleton, biogenetically derived from a Diels–Alder reaction between derivatives of 11 and 13. Compound 2 represents a rare sulfur-containing alkaloid derived from the known hydroquinone 13. Compounds 1, 10 and 12 showed strong cytotoxicity against the L5178Y mouse lymphoma cell line with IC50 values of 1.8, 1.0 and 1.1 μM, respectively. Compound 3 exhibited moderate antitubercular activity against Mycobacterium tuberculosis with a MIC value of 12.5 μM.

Co-cultivation of the endophytic fungus Fusarium tricinctum with Streptomyces lividans on solid rice medium led to the production of four new naphthoquinone dimers, fusatricinones A–D (1–4), and a new lateropyrone derivative, dihydrolateropyrone (5), that were not detected in axenic fungal controls. In addition, four known cryptic compounds, zearalenone (7), (−)-citreoisocoumarin (8), macrocarpon C (9) and 7-hydroxy-2-(2-hydroxypropyl)-5-methylchromone (10), that were likewise undetectable in extracts from fungal controls, were obtained from the co-culture extracts. The known antibiotically active compound lateropyrone (6), the depsipeptides enniatins B (11), B1 (12) and A1 (13), and the lipopeptide fusaristatin A (14), that were present in axenic fungal controls and in co-culture extracts, were upregulated in the latter. The structures of the new compounds were elucidated by 1D and 2D NMR spectra as well as by HRESIMS data. The relative and absolute configuration of dihydrolateropyrone (5) was elucidated by TDDFT-ECD calculations.

Endophytic microorganisms constitute a prolific source of bioactive compounds mainly in the field of antineoplastic compounds and anti-infective agents. This chapter provides an overview on bioactive secondary metabolites from endophytes that were reported within the last five years (2013-2018), highlighting their often-unique chemical structures and/or their mechanism(s) of action.

Two new xanthone derivatives, 12-dimethoxypinselin ( 1 ) and 12- O -acetyl-AGI-B4 ( 2 ), as well as two new phenolic bisabolane-type sesquiterpenes, 11,12-dihydroxysydonic acid ( 15 ) and 1-hydroxyboivinianic acid ( 16 ), together with one new alkaloid, scopulamide ( 21 ) and one new α-pyrone derivative, scopupyrone ( 26 ), in addition to twenty-three known compounds ( 3 – 14 , 17 – 20 , 22 – 25 , 27 – 29 ) were isolated from solid rice cultures of the marine-derived fungus Scopulariopsis sp. obtained from the Red Sea hard coral Stylophora sp. All compounds were unambiguously identified through extensive NMR spectroscopic analyses, and by comparison with the literature. Marfey's reaction was performed to determine the absolute configuration of scopulamide ( 21 ) and TDDFT-ECD calculations were used to assign the configuration of AGI-B4 ( 3 ) and scopupyrone ( 26 ). All isolated compounds were evaluated for their cytotoxicity against L5178Y mouse lymphoma cells and the structure-activity relationships were discussed.

Chemical investigation of the aerial parts of Iris lactea afforded three new flavone C -glycosides including 4‴- O -acetyl-embinin ( 1 ), 2‴,4‴- O -diacetyl-embinin ( 2 ) and 6″,4‴- O -diacetyl-embinin ( 3 ) along with the known analogue embinin ( 4 ). Their structures were elucidated by 1D and 2D NMR spectroscopic analysis as well as by HRESIMS data. The sugars were characterized following acid hydrolysis of the respective glycosides and TLC analysis compared to known standards. Duplicated signals can be observed in the NMR spectra, indicating the presence of rotamers caused by rotational hindrance around the glycosyl-flavone C C linkage. All isolated compounds were tested for their antimicrobial and cytotoxic activities but found to be inactive.

Co-cultivation of the endophytic fungus

A comparative study on the metabolic profile of the sponge-associated fungus Aspergillus carneus using the OSMAC approach was conducted. The fungal strain was fermented on three different media including solid rice medium with or without sea salt and modified Czapek medium. Three new natural products, isopropylchaetominine (1), isoterrelumamide A (2) and 5′-epi-averufanin (3), together with fourteen known compounds (4–17) were isolated. The structures of the new compounds were established by 1D and 2D NMR spectroscopic analysis as well as by HRESIMS. Compound 2 was only found when the fungus was cultivated on modified Czapek medium, whereas compounds 4, 7, 11, 12, and 14 were only detected in fungal extracts from solid rice media lacking sea salt. Compounds 8 and 13 on the other hand were only found when A. carneus was cultured on solid rice with sea salt. The cytotoxic and antimicrobial activities of all isolated compounds were evaluated. Compounds 1, 9 and 17 showed strong cytotoxicity against the mouse lymphoma cell line L5178Y with IC50 values of 0.4, 0.3 and 0.2 μM, respectively. In addition, compounds 3, 5 and 6 showed inhibitory activity against different Gram-positive bacterial strains with MIC values ranging from 2.3 to 18.4 μg/mL.

A new depsidone derivative botryorhodine I (1), along with eight known compounds (2-9) were obtained from solid rice cultures of the fungal strain, Lasiodiplodia theobromae M4.2-2 isolated from a mangrove sediment sample. The structures of the isolated compounds were elucidated on the basis of 1 D and 2 D NMR analysis as well as by HRESIMS. All compounds were evaluated for their cytotoxic potential against the mouse lymphoma cell line L5178Y as well as for their antibacterial activities against a panel of Gram-positive and Gram-negative bacterial strains. Compound 3 revealed potent cytotoxic activity with an IC50 of 7.3 µM whereas compound 7 showed selective anti-bacterial activity against different S. aureus and E. faecium bacterial strains with MIC value of 25 µg/ml.

Two new isocoumarin dimers (1 and 2) and one new dihydroquinolone derivative (3) were isolated from Aspergillus versicolor, an endophyte derived from leaves of the Egyptian water hyacinth Eichhornia crassipes (Pontederiaceae), together with ten other known metabolites. Chemical structures of the isolated metabolites were determined based on HRESIMS, extensive 1D and 2D NMR spectroscopy. The relative and absolute configurations of the new natural products were established by ROESY and electronic circular dichroism (ECD) spectroscopy, respectively. The axial chirality of the isocoumarin 7,7′-homodimers (1 and 2) was deduced by TDDFT-ECD calculations. All isolated compounds were assessed for their antimicrobial, antitubercular and cytotoxic activities. Several tested compounds revealed significant cytotoxic activity against mouse lymphoma L5178Y cell line with IC50 values ranging from

The marine environment is a prolific source of bioactive compounds. During the last decades, research on marine-derived plants, animals, and microbes has provided an impressive number of structurally diverse anti-infective agents with antibacterial, antifungal, antiprotozoal, or antiviral activities. Moreover, several of these compounds possess novel mechanisms of action, which underlines their potential as leads in drug discovery. The present chapter provides an overview on marine-derived anti-infective agents, covering the literature between 2010 and 2016, with special focus on their structural features and mechanisms of action.

Chromatographic analysis of the ethyl acetate extract of the fungus Penicillium sp., which was isolated from the sediment of the hyper saline lake Wadi El-Natrun in Egypt, afforded two new isochromans (1 and 2) and a new isocoumarin derivative (3), along with six known compounds (4–9). The planar structures of new compounds were unequivocally elucidated on the basis of extensive 1D- and 2D-NMR spectroscopy as well as HRESIMS. The relative configurations of the new compounds were established by analysis of the coupling constants as well as through ROESY experiments, while the absolute configurations were determined by comparison of the [α]D values and by plausible biosynthetic considerations. Compounds (1–6) were found to share (3S) configuration. All compounds demonstrated a weak to moderate cytotoxic activity against the murine lymphoma L5178Y cell line.

Two new epidithiodiketopiperazines, pretrichodermamide C (1) and N-methylpretrichodermamide B (2) were isolated from the fungus Penicillium sp., derived from the sediment of a hyper saline lake located at Wadi El-Natrun in Egypt. The structures of 1 and 2 were unambiguously determined on the basis of one- and two-dimensional NMR spectroscopy and by high-resolution mass spectrometry, as well as by comparison with the literature. Compound 2 showed pronounced cytotoxicity against the murine lymphoma L5178Y cell line with an IC50 value of 2 μM.

The marine-derived fungus Talaromyces rugulosus isolated from the Mediterranean sponge Axinella cannabina and cultured on solid rice medium yielded seventeen lactone derivatives including five butenolides (1–5), seven (3S)-resorcylide derivatives (6–12), two butenolide-resorcylide dimers (13 and 14), and three dihydroisocoumarins (15–17). Among them, fourteen compounds (1–3, 6–16) are new natural products. The structures of the isolated compounds were elucidated by 1D and 2D NMR (Nuclear Magnetic Resonance) spectroscopy as well as by ESI-HRMS (ElectroSpray Ionization-High Resolution Mass Spectrometry). TDDFT-ECD (Time-Dependent Density Functional Theory-Electronic Circular Dichroism) calculations were performed to determine the absolute configurations of chiral compounds. The butenolide-resorcylide dimers talarodilactones A and B (13 and 14) exhibited potent cytotoxicity against the L5178Y murine lymphoma cell line with IC50 values of 3.9 and 1.3 µM, respectively.

This chapter provides an overview of successful examples that highlight the power of the one strain many compounds (OSMAC) approach or of microbial cocultivation for an elicitation of bioactive fungal natural products that resulted either in an enhanced accumulation of constitutively present compounds, and/or in an accumulation of new natural compounds missing in axenic control cultures. The OSMAC concept is applied to explore changes of microbial metabolite profiles influenced by changing fermentation conditions, such as different media, different temperature regimes, different culture vessels, and other factors. Another approach that has proven highly successful in triggering the activation of silent biosynthetic gene clusters is the cocultivation of two or more different microbes together in one culture vessel rather than maintaining pure cultures. This strategy mimics the natural microbial ecosystem, defined as microbiome, where the microorganisms interact with each other in synergistic and/or antagonistic relationships, which are the driving ecological forces for triggering secondary metabolite biosynthesis.

Fourteen new natural products, namely, 2-[(Z)-styryl]-5-geranylresorcin-1-carboxylic acid (1), amorfrutin D (2), 4-O-demethylamorfrutin D (3), 8-geranyl-3,5,7-trihydroxyflavanone (4), 8-geranyl-5,7,3′-trihydroxy-4′-methoxyisoflavone (5), 6-geranyl-5,7,3′-trihydroxy-4′-methoxyisoflavone (6), 8-geranyl-7,3′-dihydroxy-4′-methoxyisoflavone (7), 3-O-demethyldalbinol (8), 6a,12a-dehydro-3-O-demethylamorphigenin (9), (6aR,12aR,5′R)-amorphigenin (10), amorphispironones B and C (11 and 12), resokaempferol 3-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside-7-O-α-l-rhamnopyranoside (13), and daidzein 7-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside (14), together with 40 known compounds, were isolated from the fruits of Amorpha fruticosa. The structures of the new compounds were elucidated by 1D and 2D NMR spectroscopic analysis as well as from the mass spectrometry data. ECD calculations were performed to determine the absolute configurations of 11 and 15. Compounds 1, 4–6, and 16–23 showed potent to moderate antibac...

The anti-neuroinflammatory meroterpenoid citreohybridonol was isolated for the first time from a sponge-derived fungus Penicillium atrovenetum. In this study, in addition to isolation and structure featuring, its unambiguous absolute configuration was determined exclusively by single crystal X-ray diffraction. The C-17-keto tautomer was clearly observed in X-ray analysis. The substance crystallises in the monoclinic space group P21 with a = 10.7496(5) A, b = 14.3286(7) A, c = 17.4909(8) A, β = 103.235(2)°, V = 2622.5(2) A3, Z = 2, Dcalcd = 1.280 g/cm3. The chirality of the asymmetric carbon atoms was as follows: C3 (S), C5 (R), C6 (S), C8 (S), C9 (R), C10 (R), C13 (R), C14 (R).

The anti-neuroinflammatory meroterpenoid citreohybridonol was isolated for the first time from a sponge-derived fungus Penicillium atrovenetum. In this study, in addition to isolation and structure featuring, its unambiguous absolute configuration was determined exclusively by single crystal X-ray diffraction. The C-17-keto tautomer was clearly observed in X-ray analysis. The substance crystallises in the monoclinic space group P21 with a = 10.7496(5) Å, b = 14.3286(7) Å, c = 17.4909(8) Å, β = 103.235(2)°, V = 2622.5(2) Å3, Z = 2, Dcalcd = 1.280 g/cm3. The chirality of the asymmetric carbon atoms was as follows: C3 (S), C5 (R), C6 (S), C8 (S), C9 (R), C10 (R), C13 (R), C14 (R).

Two new eremophilane-type sesquiterpenes, carperemophilanes A and B (1–2), three new maleimide-bearing compounds, carpesiumaleimides A–C (3–5), along with a known sesquiterpene, carabrol (6), were isolated from the ethanol extract of Carpesium abrotanoides L. Their structures were elucidated by analysis of their NMR and MS data as well as by comparison with the literature. The absolute configuration of carperemophilane A (1) was determined by single-crystal X-ray diffraction analysis. All isolated compounds (1–6) were evaluated in vitro for cytotoxicity against two human cancer cell lines MDA-MB-231 and HGC-27 using the MTT method. Compounds 1, 2 and 6 showed cytotoxic activities with IC50 values ranging from 7.45 to 37.35 μM.

Chemical investigation of the EtOAc extract of the mangrove-derived endophyte Corynespora cassiicola , isolated from Laguncularia racemosa (Combretaceae), afforded five new secondary metabolites, named coryoctalactones A–E ( 1 – 5 ). The structures of the new compounds were determined on the basis of 1D- and 2D-NMR spectroscopy as well as high-resolution mass spectrometry. The absolute configuration of the side chain in 1 – 3 and 5 were tentatively deduced based on biogenetic consideration in comparison with xestodecalactones, previously isolated from C. cassiicola . All isolated compounds were evaluated for their antimicrobial, cytotoxic, and antitrypanosomal activities.

The endophytic fungus Penicillium citrinum was isolated from a fresh stem of the Moroccan plant Ceratonia siliqua. Extracts of P. citrinum grown on rice and white bean media yielded five new compounds, namely, citriquinochroman (1), tanzawaic acids G and H (2 and 3), 6-methylcurvulinic acid (4), 8-methoxy-3,5-dimethylisoquinolin-6-ol (5), and one new natural product, 1,2,3,11b-tetrahydroquinolactacide (6), which had previously been described as a synthetic compound. In addition, 13 known compounds including seven alkaloids and six polyketides were isolated. The structures of the new compounds were unambiguously determined on the basis of one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. Citriquinochroman (1) features a new skeleton, consisting of quinolactacide and (3S)-6-hydroxy-8-methoxy-3,5-dimethylisochroman linked by a C-C bond. 1,2,3,11b-Tetrahydroquinolactacide (6) may be a biogenetic precursor of quinolactacide. Citriquinochroman (1) showed cytotoxicity against the murine lymphoma L5178Y cell line with an IC50 value of 6.1 μM, while the other compounds were inactive (IC50 >10 μM) in this assay.

Two new metabolites, embellicines A and B (1 and 2), were isolated from the EtOAc extract of the fungus Embellisia eureka , an endophyte of the Moroccan plant Cladanthus arabicus (Asteraceae). The structures of these new compounds were determined on the basis of extensive one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configuration of embellicine A (1) was determined by TDDFT ECD calculations of solution conformers, whereas that of embellicine B (2) was deduced based on ROESY correlations and on biogenetic considerations in comparison to 1. Both embellicines (1 and 2) are cytostatic, cytotoxic, and inhibit NF-κB transcriptional activity, indicating that inhibition of NF-κB may be a possible mechanism of action of these compounds. Embellicine B (2) was the most active compound encountered in this study and acts at nanomolar concentrations without affecting tumor microenvironment.

Three new polyketides (-)-1, (+)-1, and 2) were isolated from the EtOAc extract of the fungus Embellisia eureka, an endophyte of the Moroccan plant Cladanthus arabicus (Asteraceae). The structures of these new compounds were determined on the basis of one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configurations of (-)-1, (+)-1, and 2 were determined by TDDFT ECD calculations of solution conformers, online HPLC-ECD analysis, and the modified Mosher method. Chirality 25:250–256, 2013. © 2013 Wiley Periodicals, Inc.

Background: Over the last two decades, deep-sea-derived fungi are considered to be a new source of pharmacologically active secondary metabolites for drug discovery mainly based on the underlying assumption that the uniqueness of the deep sea will give rise to equally unprecedented natural products. Indeed, up to now over 200 new metabolites have been identified from deep-sea fungi, which is in support of the statement made above. Results: This review summarizes the new and/or bioactive compounds reported from deepsea- derived fungi in the last six years (2010 – October 2016) and critically evaluates whether the data published so far really support the notion that these fungi are a promising source of new bioactive chemical entities.

Scopulariopsis sp. isolated from the Red Sea hard coral Stylophora sp. yielded two new triterpenoids (1–2) and a new naphthoquinone derivative (8) when cultured on white beans. In addition, fourteen known compounds including three triterpene analogues (3–5), two sesquiterpenoids (6–7), two polyketides (9–10) and seven nitrogenous compounds (11–17) were isolated. All structures were determined through extensive analysis of the NMR and MS data as well as by comparison with literature data. All isolated compounds were evaluated for their cytotoxic, antibacterial and antitubercular activities. However, none of them showed significant activity.

Chemical investigation of the MeOH extract of the sponge Acanthostrongylophora ingens afforded the new manzamine derivative ircinal E (1), in addition to six known metabolites (2-7). The structure of the new compound was unequivocally elucidated using one- and two-dimensional NMR spectroscopy, as well as high-resolution mass spectrometry. Compounds 1-6 exhibited strong to moderate cytotoxicity against the murine lymphoma L5178Y cell line with IC50 values ranging from 2.8 to 21.7 µM.