Steroid Derivatives Research Articles

ADMET profiles of selected anabolic steroid derivatives

There is control over steroids use and marketing, but also new compounds that mimic their effects, steroid derivatives, are being synthesized. They are frequently produced as dietary supplements intended to improve physical activity, and usually no information is provided regarding their composition, dosages, and efficacy or safety. In this study, a computational approach was used to evaluate the absorption, distribution, metabolism, excretion and toxicity (ADMET) profiles of several steroid derivatives: methasterone, methyl-1-testosterone, 4-hydroxytestosterone, methyldienolone, methyltrienolone and 19-nor-5-androstenedione. The following computational prediction tools were applied: admetSAR2.0, ADMETLab2.0, Endocrine Disruptome, PredSkin3.0. All investigated compounds showed good human intestinal absorption, are not able to penetrate the blood-brain barrier and inhibit cytochrome P450 enzymes involved in the metabolism of xenobiotics. These compounds have potential for skin sensitisation, induce reproductive toxicity and endocrine disruption, and have a low potential for hepatotoxicity and respiratory toxicity. It is important that the results of the study are known by those exposed at workplaces where these compounds are produced and packed as well as by consumers. These predictions can also guide the experimental evaluation of the possible toxicity of the investigated compounds, the results of which can be further used for purposes of regulating the use of these steroid derivatives.

Breaking boundaries in diabetic nephropathy treatment: design and synthesis of novel steroidal SGLT2 inhibitors.

The activity of sodium glucose co-transporter 2 (SGLT2) has always been an important parameter influencing chronic kidney disease in type-2 diabetic patients. Herein, we have meticulously designed, synthesized, and evaluated several novel steroidal pyrimidine molecules that possess the capability to successfully bind to the SGLT2 protein and inhibit its activity, thereby remedying kidney-related ailments in diabetic patients. The lead steroidal pyrimidine compounds were selected after virtually screening from a library of probable N-heterocyclic steroidal scaffolds. A nano-catalyzed synthetic route was also explored for the synthesis of the steroidal pyrimidine analogs demonstrating an environmentally benign protocol. Extensive in vitro investigations encompassing SGLT2 screening assays and cell viability assessments were conducted on the synthesized compounds. Among the steroidal pyrimidine derivatives evaluated, compound 9a exhibited the highest SGLT2 inhibition activity and underwent further scrutiny. Western blot analysis was employed to determine the impact of 9a on inflammatory and fibrotic proteins, aiming to elucidate its mechanism of action. Additionally, in silico analyses were performed to illuminate the structural dynamics and molecular interaction mechanism of 9a. The overall investigation is crucial for advancing the development of the next generation of anti-diabetic drugs.

Exploring 7β-amino-6-nitrocholestens as COVID-19 antivirals: in silico, synthesis, evaluation, and integration of artificial intelligence (AI) in drug design: assessing the cytotoxicity and antioxidant activity of 3β-acetoxynitrocholestane.

In light of the ongoing pandemic caused by SARS-CoV-2, effective and clinically translatable treatments are desperately needed for COVID-19 and its emerging variants. In this study, some derivatives, including 7β-aminocholestene compounds, and 3β-acetoxy-6-nitrocholesta-4,6-diene were synthesized, in quantitative yields from 7β-bromo-6-nitrocholest-5-enes (1-3) with a small library of amines. The synthesized steroidal products were then thoroughly characterized using a range of physicochemical techniques, including IR, NMR, UV, MS, and elemental analysis. Next, a virtual screening based on structures using docking studies was conducted to investigate the potential of these synthesized compounds as therapeutic candidates against SARS-CoV-2. Specifically, we evaluated the compounds' binding energy of the reactants and their products with three SARS-CoV-2 functional proteins: the papain-like protease, 3C-like protease or main protease, and RNA-dependent RNA polymerase. Our results indicate that the 7β-aminocholestene derivatives (4-8) display intermediate to excellent binding energy, suggesting that they interact strongly with the receptor's active amino acids and may be promising drug candidates for inhibiting SARS-CoV-2. Although the starting steroid derivatives; 7β-bromo-6-nitrocholest-5-enes (1-3) and one steroid product; 3β-acetoxy-6-nitrocholesta-4,6-diene (9) exhibited strong binding energies with various SARS-CoV-2 receptors, they did not meet the Lipinski Rule and ADMET properties required for drug development. These compounds showed either mutagenic or reproductive/developmental toxicity when assessed using toxicity prediction software. The findings based on structure-based virtual screening, suggest that 7β-aminocholestaines (4-8) may be useful for reducing the susceptibility to SARS-CoV-2 infection. The docking pose of compound 4, which has a high score of -7.4 kcal mol-1, was subjected to AI-assisted deep learning to generate 60 AI-designed molecules for drug design. Molecular docking of these AI molecules was performed to select optimal candidates for further analysis and visualization. The cytotoxicity and antioxidant effects of 3β-acetoxy-6-nitrocholesta-4,6-diene were tested in vitro, showing marked cytotoxicity and antioxidant activity. To elucidate the molecular basis for these effects, steroidal compound 9 was subjected to molecular docking analysis to identify potential binding interactions. The stability of the top-ranked docking pose was subsequently assessed using molecular dynamics simulations.

COMPUTATIONAL STUDIES AND GREEN SYNTHESIS OF BENZIMIDAZOLES THROUGH SEQUENTIAL OXIDATIVE CYCLISATION OF ARYLDIAMINES IN SOLVENT-FREE CONDITIONS

Benzimidazoles were synthesized under solvent-free conditions using Ionic Liquids (IL), specifically 1-Pentyl-3- methylimidazolium bromide ([pmim]Br), derived from aryl aldehydes and phenylenediamine. A comparative study of yields was conducted by reacting aryl aldehydes with both electron-donating and electron-withdrawing groups with substituted o-phenylenediamines, resulting in the formation of 2-phenylbenzimidazoles via cyclization. The yield of final products, optimum reaction conditions, plausible mechanism of the reaction, and the effect of substitutions at various positions of either of the reactants are presented in this paper. Computational studies have been done to explore the possibility of synthesized compounds for anticancer activity. Molecular docking studies were conducted to explore the inhibitory effects of steroidal derivatives against the estrogen receptor-derived Mutants [PDB ID: 2ITO]. The docking results of all compounds revealed significant inhibitory activity against the estrogen receptor 2ITO, with binding energy (ΔG) values for compounds 3a, 3b, 3c, 3d, 3e, 3f, and 3g against protein 2ITO recorded as -7.1 Kcal/mole, -7.3 Kcal/mole, -7.2 Kcal/mole, -7.8 Kcal/mole, -7.5 Kcal/mole, -7.6 Kcal/mole, and -7.6 Kcal/mole respectively.

Design and synthesis of a potential candidate molecule designated as Diosgenin-Aceclofenac ester as an anticancer agent on SiHa cell line, it's spectroscopic, DFT and molecular docking studies

In the present study a new steroidal derivative i.e. Diosgenin-Aceclofenac conjugate was synthesized using Steglich esterification. The ester derivative obtained was purified through column chromatography and its structure was confirmed using various spectroscopic techniques like 1H NMR, 13C NMR, IR and mass spectrometry. Computational data was obtained using Gaussian 09 program using B3LYP function and 6-31G (d, p) basic set and the molecular structure was visualized with the help of Gauss View. The energy for the optimized compound 3 was found to be -3096.35 au which possessed a C1 point group symmetry. The pymol and discovery studio softwares were used for Molecular Docking. The results show increase in first static hyperpolarizability and activity with incorporated acceptors being responsible for structural variation. The synthesized compound was evaluated for anti-cancer activity on SiHa cell line which demonstrated an appreciable activity as indicated by the IC50 values. The computational analysis data and experimental data were in conformation with each other.

Biotransformation of Δ1-Progesterone Using Selected Entomopathogenic Filamentous Fungi and Prediction of Its Products' Bioactivity.

This research aimed at obtaining new derivatives of pregn-1,4-diene-3,20-dione (Δ1-progesterone) (2) through microbiological transformation. For the role of catalysts, we used six strains of entomopathogenic filamentous fungi (Beauveria bassiana KCh J1.5, Beauveria caledonica KCh J3.3, Isaria fumosorosea KCh J2, Isaria farinosa KCh KW1.1, Isaria tenuipes MU35, and Metarhizium robertsii MU4). The substrate (2) was obtained by carrying out an enzymatic 1,2-dehydrogenation on an increased scale (3.5 g/L) using a recombinant cholest-4-en-3-one Δ1-dehydrogenase (AcmB) from Sterolibacterium denitrificans. All selected strains were characterized by the high biotransformation capacity for the used substrate. As a result of the biotransformation, six steroid derivatives were obtained: 11α-hydroxypregn-1,4-diene-3,20-dione (3), 6β,11α-dihydroxypregn-1,4-diene-3,20-dione (4), 6β-hydroxypregn-1,4-diene-3,11,20-trione (5), 6β,17α-dihydroxypregn-1,4-diene-3,20-dione (6), 6β,17β-dihydroxyandrost-1,4-diene-3-one (7), and 12β,17α-dihydroxypregn-1,4-diene-3,20-dione (8). The results show evident variability of the biotransformation process between strains of the tested biocatalysts from different species described as entomopathogenic filamentous fungi. The obtained products were tested in silico using cheminformatics tools for their pharmacokinetic and pharmacodynamic properties, proving their potentially high biological activities. This study showed that the obtained compounds may have applications as effective inhibitors of testosterone 17β-dehydrogenase. Most of the obtained products should, also with a high probability, find potential uses as androgen antagonists, a prostate as well as menopausal disorders treatment. They should also demonstrate immunosuppressive, erythropoiesis-stimulating, and anti-inflammatory properties.

Antiproliferative activity of the novel CYP17A1 inhibitor alsevirone

BACKGROUND: Prostate cancer is the most frequently diagnosed type of cancer in men in developed countries. It is dependent upon androgens and could be effectively combated by androgen deprivation therapy. Reduction of androgen synthesis can be accomplished through the inhibition of the enzyme 17α-hydroxylase/17.20-lyase (CYP17A1), which catalyzes two sequential reactions in the production of androgens. Steroid derivatives modified with nitrogen-containing heterocycles attract attention as antineoplastic agents for prostate cancer treatment due to their inhibitory potential against CYP17A1.
 AIM: Evaluate cytotoxic activity and antitumor effects of the synthesized alsevirone in comparison with abiraterone.
 METHODS: Cytotoxicity was evaluated using MTT test. Anticancer effect was researched in vivo in prostate cancer xenograft models 22Rv1 and DU145 in Balb/c nude mice. Testosterone concentration was determined using an enzyme-linked immunosorbent assay in blood serum of BDF1 mice.
 RESULTS: Alsevirone demonstrated cytotoxic activity in prostate cancer cells: DU145 (23.8±1.2 µM vs 151.4±23.7 µM for abiraterone), 22Rv1 (35.9±5.6 µM vs 109.9±35.2 µM for abiraterone) and LNCaP (22.9±0.5 µM vs 28.8±1.6 µM for abiraterone). Testosterone concentration in blood serum of BDF1 mice reduced by 80% after 10-day treatment. Inhibition of the tumors’ growth in 22Rv1 xenograft model was statistically significant when using alsevirone in comparison with the control group: average tumor volume was 171.6±50.1 mm3 (р=0.022) vs 424.2±70.3 mm3 in control, with tumor growth inhibition index of 59%.
 CONCLUSIONS: Alsevirone has a higher cytotoxic potential against prostate cancer cells (DU145, LNCaP and 22Rv1) compared to abiraterone. Alsevirone demonstrated the ability to reduce the concentration of testosterone in the blood serum of BDF1 mice, and statistically significant antitumor activity in 22Rv1 xenograft models.

Comparative Metabolomics Study of Four Kinds of Xihu Longjing Tea Based on Machine Fixing and Manual Fixing Methods.

China Xihu Longjing tea is famous for its good flavor and quality. However, information on its related metabolites, except for flavonoids, is largely deficient. Different processing methods for China Xihu Longjing tea fixing-by machines at both the first and second step (A1), first step by machine and second step by hand (A2), first step by hand and second step by machine (A3), and by hand at both the first and second step (A4)-were compared using a UHPLC-QE-MS-based metabolomics approach. Liquid chromatography-mass spectrometry was used to analyze the metabolic profiles of the processed samples. A total of 490 metabolites (3 alkaloids, 3 anthracenes, 15 benzene and substituted derivatives, 2 benzopyrans, 13 coumarins and derivatives, 128 flavonoids, 4 furanoid lignans, 16 glycosides and derivatives, 5 indoles and derivatives, 18 isocoumarins and derivatives, 4 chalcones and dihydrochalcones, 4 naphthopyrans, 3 nucleosides, 78 organic acids and derivatives, 55 organooxygen compounds, 5 phenols, 109 prenol lipids, 3 saccharolipids, 3 steroids and steroid derivatives, and 17 tannins) were identified. The different metabolic profiles were distinguished using PCA and OPLS-DA. There were differences in the types and contents of the metabolites, especially flavonoids, furanoid lignans, glycosides and derivatives, organic acids and derivatives, and organooxygen compounds. There was a positive correlation between flavonoid metabolism and amino acid metabolism. However, there was a negative correlation between flavonoid metabolism and amino acid metabolism, which had the same trend as prenol lipid metabolism and tannins. This study provides new valuable information regarding differences in the metabolite profile of China Xihu Longjing tea processed based on machine fixing and on manual fixing methods.

Synthesis of Sulfonyl Arenes via Hydroxy/Amino‐Benzannulation of Sulfonyl Enynals

AbstractAn assorted set of sulfonyl arenes such as β‐naphthylamines, β‐naphthols, phenols and naphthalenes could be accessed in a divergent manner by base‐mediated annulation of sulfonyl enynals. The strategy is extended to the synthesis of heterocycles such as carbazole, quinoline and benzothiophene. Benzannulation is demonstrated on derivatives of natural steroids like estrone and cholesterol.

Two new steroids from the medicinal plant Physalis peruviana L.

Two new steroid derivatives [Withaperuvin O: (20S, 22R)−5α, 6β, 14α, 17β, 20α-pentahydroxy-1-oxowithan-24-en-22,26-olide (1) and Withaperuvinoside: (24E, 22R)−1α,3β-dihydroxyergosta-5,24-dienolide-26-O-β-D-glucopyranosyl (1→2)-β-D-glucopyrano-side] (2) were isolated from the methanolic extract of the whole plant of Physalis peruviana together with six known compounds: saringosterol (3), physalindicanol B (4), physalindicanol A (5), perulactone (6), β-sitosterol (7), and β-sitosterol-3-O-β-D-glucopyranoside (8). Their structures were established on the basis of spectroscopic (1D and 2D NMR) and spectrometric evidence and by comparison with data described in the literature. Compounds 1 and 2 are closely related to compounds previously isolated from the same plant. The antibacterial activity of the crude extract, EtOAc and n-BuOH fractions as well as compounds 1-6 was assessed by determining the minimum inhibitory concentration (MIC) using the broth microdilution method against five pathogenic bacterial strains. The methanolic extract and the EtOAc fraction showed a weak activity against all the tested bacterial strains with MICs values between 128 and 512 µg/mL, except for Staphylococcus aureus. Compounds 1 and 2 were inactive against the tested microorganisms.

Promiscuity and Selectivity of Hydroxysteroid Dehydrogenases in the Biocatalyzed Reduction of 1,2‐Diketones

AbstractHydroxysteroid dehydrogenases (HSDHs) are NAD(P)H‐dependent alcohol dehydrogenases (ADHs) known for their exceptional stereo‐ and regioselectivity when acting on natural substrates, including neutral steroids, bile acids, and various steroid derivatives. Notably, in recent studies this specific subfamily of oxidoreductases has displayed intriguing substrate promiscuity, exhibiting the capacity to accommodate a diverse array of substrates, such as sterically hindered ketones and even α‐keto esters. Herein, the promiscuous nature of HSDHs was further explored by investigating their catalytic activity with representative 1,2‐diketones. This set encompasses symmetric aliphatic/aromatic diketones – namely, 3,4‐hexandione and benzil – as well as the asymmetric synthon 1‐phenyl‐1,2‐propanedione. In the case of 3,4‐hexandione, substrate conversion and selectivity closely resembled that previously observed with aliphatic α‐keto esters. On the contrary, a more heterogeneous behavior was observed in the case of aromatic substrates, with diverse performances in terms of conversions and stereo‐ or regioselectivity. Additionally, docking studies were carried out to get a deeper insight in the stereochemistry of 1,2‐diketones reduction catalyzed by the broad substrate scope and steroid‐active ketoreductase Is2‐SDR.

New Steroidal Selenides as Proapoptotic Factors.

Cytostatic and pro-apoptotic effects of selenium steroid derivatives against HeLa cells were determined. The highest cytostatic activity was shown by derivative 4 (GI50 25.0 µM, almost complete growth inhibition after three days of culture, and over 97% of apoptotic and dead cells at 200 µM). The results of our study (cell number measurements, apoptosis profile, relative expression of apoptosis-related APAF1, BID, and mevalonate pathway-involved HMGCR, SQLE, CYP51A1, and PDHB genes, and computational chemistry data) support the hypothesis that tested selenosteroids induce the extrinsic pathway of apoptosis by affecting the cell membrane as cholesterol antimetabolites. An additional mechanism of action is possible through a direct action of derivative 4 to inhibit PDHB expression in a way similar to steroid hormones.

Molecular Cloning, Heterologous Expression, Purification, and Evaluation of Protein-Ligand Interactions of CYP51 of Candida krusei Azole-Resistant Fungal Strain.

Due to the increasing prevalence of fungal diseases caused by fungi of the genus Candida and the development of pathogen resistance to available drugs, the need to find new effective antifungal agents has increased. Azole antifungals, which are inhibitors of sterol-14α-demethylase or CYP51, have been widely used in the treatment of fungal infections over the past two decades. Of special interest is the study of C. krusei CYP51, since this fungus exhibit resistance not only to azoles, but also to other antifungal drugs and there is no available information about the ligand-binding properties of CYP51 of this pathogen. We expressed recombinant C. krusei CYP51 in E. coli cells and obtained a highly purified protein. Application of the method of spectrophotometric titration allowed us to study the interaction of C. krusei CYP51 with various ligands. In the present work, the interaction of C. krusei CYP51 with azole inhibitors, and natural and synthesized steroid derivatives was evaluated. The obtained data indicate that the resistance of C. krusei to azoles is not due to the structural features of CYP51 of this microorganism, but rather to another mechanism. Promising ligands that demonstrated sufficiently strong binding in the micromolar range to C. krusei CYP51 were identified, including compounds 99 (Kd = 1.02 ± 0.14 µM) and Ch-4 (Kd = 6.95 ± 0.80 µM). The revealed structural features of the interaction of ligands with the active site of C. krusei CYP51 can be taken into account in the further development of new selective modulators of the activity of this enzyme.

Investigation of corticosteroid-NSAID prodrugs for TNF-α and IL6 receptors, their characterization, single crystal XRD and DFT studies: A combined experimental and theoretical approach

In continuation of our research towards the synthesis of steroidal derivatives, we have synthesized corticosteroids-NSAIDs derivatives 3i-3p as potent anti-inflammatory agents. The products obtained have been characterized using elemental analysis, spectroscopic techniques (FT-IR, 1H NMR, 13C NMR, UV–Vis and mass spectrometry) and product 3k has also been characterized with the help of single crystal X-ray crystallography. The inhibition of pro-inflammatory cytokines is a key approach to abate severe inflammation. In this work a series of corticosteroids-NSAIDs derivatives are reported whose activity were performed on RAW264.7 cell line and have been identified as potential TNF alpha and IL6 inhibitors. Our work demonstrates that these corticosteroid derivatives may be useful for the development of anti-inflammatory agents. Among these derivatives, 11,17-dihydroxy-3,20-diketo-pregn-1,4-diene-21-yl-2-(1,8‑diethyl-1,3,4,9-tetrahydropyrano[3,4-β]indol-1-yl)acetate (3j) was identified as the most potent anti-inflammatory agent, which showed significant anti-inflammatory activity by inhibiting the LPS-induced pro-inflammatory mediator TNF-α and IL6 in a dose-dependent manner without any cytotoxicity.

The oxidation of steroid derivatives by the CYP125A6 and CYP125A7 enzymes from Mycobacterium marinum

The members of the bacterial cytochrome P450 (CYP) monooxygenase family CYP125, catalyze the oxidation of steroid derivatives including cholesterol and phytosterols, as the initial activating step in their catabolism. However, several bacterial species contain multiple genes encoding CYP125 enzymes and other CYP enzymes which catalyze cholesterol/cholest-4-en-3-one hydroxylation. An important question is why these bacterium have more than one enzyme with overlapping substrate ranges capable of catalyzing the terminal oxidation of the alkyl chain of these sterols. To further understand the role of these enzymes we investigated CYP125A6 and CYP125A7 from Mycobacterium marinum with various cholesterol analogues. These have modifications on the A and B rings of the steroid and we assessed the substrate binding and catalytic activity of these with each enzyme. CYP125A7 gave similar results to those reported for the CYP125A1 enzyme from M. tuberculosis. Differences in the substrate binding and catalytic activity with the cholesterol analogues were observed with CYP125A6. For example, while cholesteryl sulfate could bind to both enzymes it was only oxidized by CYP125A6 and not by CYP125A7. CYP125A6 generated higher levels of metabolites with the majority of C-3 and C-7 substituted cholesterol analogues such 7-ketocholesterol. However, 5α-cholestan-3β-ol was only oxidized by CYP125A7 enzyme. The cholest-4-en-3-one and 7-ketocholesterol-bound forms of the CYP125A6 and CYP125A7 enzymes were modelled using AlphaFold. The structural models highlighted differences in the binding modes of the steroid derivatives within the same enzyme. Significant changes in the binding mode of the steroids between these CYP125 enzymes and other bacterial cholesterol oxidizing enzymes, CYP142A3 and CYP124A1, were also seen. Despite this, all these models predicted the selectivity for terminal methyl hydroxylation, in agreement with the experimental data.

Synthesis and Antiproliferative Activity Evaluation of B-norcholesterol-6- amide Compounds.

The structure modification of steroids is commonly used to change the biological activity of steroids in medicinal chemistry. In recent years, it has been found that some derivatives derived from the structural modification of cholesterol display good inhibitory activity against tumor cell proliferation in vitro</i>. Using cholesterol as the starting material, different types of B-norcholesterol-6-amide derivatives were synthesized by the reaction of 6-carboxyl-B-norcholesterol with different alkyl amines or 6-amino-B-norcholesterol with different acyl chlorides. The inhibitory activity of compounds on the proliferation of tumor cell lines was investigated by the MTT method. The results showed that the B-norcholesterol-6-amide compounds displayed distinct cytotoxicity against Sk-Ov-3 cells but caused no obvious damage against HEK-293T cells. Additionally, the steroidal amide derivatives formed from 6-amino-B-norcholesterol showed stronger cytotoxicity than those produced from 6-carboxyl-B-norcholesterol. Specially, compounds with chloroalkyl structure displayed significant inhibitory activity against all tumor cells tested. Among them, compounds 19-21 showed cytotoxicity like 2-methoxyestradiol as a positive control, and the IC</i>₅₀ value of compound 20 on HeLa cells was 3.9 μM. After introducing chloroalkyl acyl groups into 6-position of 6-amino-B-norcholesterol, the cytotoxicity of resulting B-norcholesterol-6-amide compounds can be greatly enhanced.

Cholesterol based mesogenic Schiff’s base derivatives with carbonate linkage: Synthesis, characterisation and photoluminescence study

ABSTRACT The steroidal derivatives have been found to be extremely good mesogens since their origin. Due to their inherent chirality, they have the potential to induce a wide variety of liquid crystalline phases, including frustrated phases, depending on the structure of the steroidal skeleton and the substituents attached. In this report, thirteen new homologous Schiff’s base derivatives were synthesised by condensing 4-n-alkoxy aniline with 4-formyl phenyl cholesteryl carbonate. All the compounds were characterised using elemental analysis, FT-IR, 1H-NMR and 13C-NMR. In order to study the liquid crystalline behaviour of the synthesised compounds, optical texture studies were carried out using polarising optical microscope in heating and cooling cycles. The derivatives showed a variety of mesophases, including chiral nematic (N*), twist grain boundary-A (TGBA), smectic A (SmA) and chiral smectic C (SmC*) phases. The thermal behaviour was determined using a differential scanning calorimeter and thermogravimetric analysis. All the synthesised compounds are UV-active and show photoluminescence in the blue emission region with good quantum yield.

Screening of Anti-Inflammatory Activity and Metabolomics Analysis of Endophytic Fungal Extracts; Identification and Characterization of Perylenequinones and Terpenoids from the Interesting Active Alternaria Endophyte.

Patients suffering from inflammatory chronic diseases are classically treated with anti-inflammatory drugs but unfortunately are highly susceptible to becoming resistant to their treatment. Finding new drugs is therefore crucial and urgent and research on endophytic fungi is a promising way forward. Endophytic fungi are microorganisms that colonize healthy plants and live within their intercellular tissues. They are able to produce a large variety of secondary metabolites while allowing their host to stay healthy. A number of these molecules are endowed with antioxidant or antimicrobial as well as cytotoxic properties, making them very interesting/promising in the field of human therapy. The aim of our study was to investigate whether extracts from five endophytic fungi isolated from plants are endowed with anti-inflammatory activity. Extracts of the endophytic fungi Alternaria alternata from Calotropis procera leaves and Aspergillus terreus from Trigonella foenum-graecum seeds were able to counteract the lipopolysaccharide (LPS) pro-inflammatory effect on THP-1 cells differentiated into macrophages. Moreover, they were able to induce an anti-inflammatory state, rendering them less sensitive to the LPS pro-inflammatory stimulus. Taken together, these results show that these both endophytic fungi could be interesting alternatives to conventional anti-inflammatory drugs. To gain more detailed knowledge of their chemical richness, phytochemical analysis of the ethyl acetate extracts of the five endophytic fungi studied was performed using HPTLC, GC-MS and LC-MS with the Global Natural Products Social (GNPS) platform and the MolNetEnhancer tool. A large family of metabolites (carboxylic acids and derivatives, steroid derivatives, alkaloids, hydroxyanthraquinones, valerolactones and perylenequinones) were detected. The purification of endophytic fungus extract of Alternaria alternate, which diminished TNF-α production of 66% at 20 µg/mL, incubated one hour before LPS addition, led to the characterization of eight pure compounds. These molecules are altertoxins I, II, III, tricycloalternarenes 3a, 1b, 2b, anthranilic acid, and o-acetamidobenzoic acid. In the future, all these pure compounds will be evaluated for their anti-inflammatory activity, while altertoxin II has been shown in the literature as the most active mycotoxin in terms of anti-inflammatory activity.

Comprehensive profiling of the metabolome in corn silage inoculated with or without Lactiplantibacillus plantarum using different untargeted metabolomics analyses

ABSTRACTSilage fermentation is a complicated biochemical process involving interactions between microbes and metabolites. However, the overall metabolome feature of ensiled forage and its response to lactic acid bacteria inoculation is poorly understood. Hence, in this study metabolome profiles of whole-plant corn silage inoculated with or without Lactiplantibacillus plantarum were characterised via solid-phase microextraction/gas chromatography/mass spectrometry (SPME-GC-MS), gas chromatography/time-of-flight mass spectrometry (GC-TOF-MS), and Liquid chromatography/Q Exactive HFX mass spectrometry (LC-QE-MS/MS) analysis. There were 2087 identified metabolites including 1143 reliably identified metabolites in fresh and ensiled whole-plant corn. After ensiling, the increased metabolites in whole-plant corn were mainly composed of organic acids, volatile organic compounds (VOC), benzene and substituted derivatives, carboxylic acids and derivatives, fatty acyls, flavonoids, indoles and derivatives, organooxygen compounds (including amines and amides), phenols, pyridines and derivatives, and steroids and steroid derivatives, which includes neurotransmitters and metabolites with aromatic, antioxidant, anti-inflammatory, and antimicrobial activities. Phenylacetaldehyde was the most abundant aromatic metabolite after ensiling. L-isoleucine and oxoproline were the major free amino acids in silage. Ensiling markedly increased the relative abundances of 3-phenyllactic acid, chrysoeriol, 6-O-acetylaustroinulin, acetylcholine, γ-aminobutyric acid, pyridoxine, and alpha-linoleic acid. Inoculation with L. plantarum remarkably changed silage VOC composition, and essential amino acids, 3-phenyllactic acid, and cinnamaldehyde compared with untreated silage. The present study does not only provide a deeper insight into metabolites of the ensiled whole-plant corn but also reveals metabolites with specific biological functions that could be much helpful in screening novel lactic acid bacteria to well ensile forages. Inoculation with L. plantarum significantly affects the metabolome in ensiled whole-plant corn.

Seasonal Monitoring of Volatiles and Antioxidant Activity of Brown Alga Cladostephus spongiosus.

Cladostephus spongiosus was harvested once a month during its growing season (from May to August) from the Adriatic Sea. Algal volatile organic compounds (VOCs) were obtained by headspace solid-phase microextraction (HS-SPME) and hydrodistillation (HD) and analysed by gas chromatography and mass spectrometry (GC-MS). The effects of air drying and growing season on VOCs were determined. Two different extraction methods (ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE)) were used to obtain ethanolic extracts of C. spongiosus. In addition, the seasonal antioxidant potential of the extracts was determined, and non-volatile compounds were identified from the most potent antioxidant extract. Aliphatic compounds (e.g., pentadecane) were predominantly found by HS-SPME/GC-MS. Hydrocarbons were more than twice as abundant in the dry samples (except in May). Aliphatic alcohols (e.g., hexan-1-ol, octan-1-ol, and oct-1-en-3-ol) were present in high percentages and were more abundant in the fresh samples. Hexanal, heptanal, nonanal, and tridecanal were also found. Aliphatic ketones (octan-3-one, 6-methylhept-5-en-2-one, and (E,Z)-octa-3,5-dien-2-one) were more abundant in the fresh samples. Benzene derivatives (e.g., benzyl alcohol and benzaldehyde) were dominant in the fresh samples from May and August. (E)-Verbenol and p-cymen-8-ol were the most abundant in dry samples in May. HD revealed aliphatic compounds (e.g., heptadecane, pentadecanal, (E)-heptadec-8-ene, (Z)-heptadec-3-ene), sesquiterpenes (germacrene D, epi-bicyclosesquiphellandrene, gleenol), diterpenes (phytol, pachydictyol A, (E)-geranyl geraniol, cembra-4,7,11,15-tetraen-3-ol), and others. Among them, terpenes were the most abundant (except for July). Seasonal variations in the antioxidant activity of the ethanolic extracts were evaluated via different assays. MAE extracts showed higher peroxyl radical inhibition activity from 55.1 to 74.2 µM TE (Trolox equivalents). The highest reducing activity (293.8 µM TE) was observed for the May sample. Therefore, the May MAE extract was analysed via high-performance liquid chromatography with high-resolution mass spectrometry and electrospray ionisation (UHPLC-ESI-HRMS). In total, 17 fatty acid derivatives, 9 pigments and derivatives, and 2 steroid derivatives were found. The highest content of pheophorbide a and fucoxanthin, as well as the presence of other pigment derivatives, could be related to the observed antioxidant activity.