scholarly journals Entomotoxic Activity of the Extracts from the Fungus, Alternaria tenuissima and Its Major Metabolite, Tenuazonic Acid

2021 ◽  
Vol 7 (9) ◽  
pp. 774
Author(s):  
Dilara Salimova ◽  
Anna Dalinova ◽  
Vsevolod Dubovik ◽  
Igor Senderskiy ◽  
Elena Stepanycheva ◽  
...  

The study of fungal antibiotics in their competitive interactions with arthropods may lead to the development of novel biorational insecticides. Extracts of Alternaria tenuissima MFP253011 obtained using various methods showed a wide range of biological activities, including entomotoxic properties. Analysis of their composition and bioactivity allowed us to reveal several known mycotoxins and unidentified compounds that may be involved in the entomotoxic activity of the extracts. Among them, tenuazonic acid (TeA), which was the major component of the A. tenuissima extracts, was found the most likely to have larvicidal activity against Galleria mellonella. In the intrahaemocoel injection bioassay, TeA was toxic to G. mellonella and of Zophobas morio with an LT50 of 6 and 2 days, respectively, at the level of 50 µg/larva. Administered orally, TeA inhibited the growth of G. mellonella larvae and caused mortality of Acheta domesticus adults (LT50 7 days) at a concentration of 250 µg/g of feed. TeA showed weak contact intestinal activity against the two phytophages, Tetranychus urticae and Schizaphis graminum, causing 15% and 27% mortality at a concentration of 1 mg/mL, respectively. TeA was cytotoxic to the Sf9 cell line (IC50 25 µg/mL). Thus, model insects such as G. mellonella could be used for further toxicological characterization of TeA.

Author(s):  
Dilara Salimova ◽  
Anna Dalinova ◽  
Vsevolod Dubovik ◽  
Igor Sendersky ◽  
Elena Stepanycheva ◽  
...  

Study of fungal antibiotics in their competitive interactions with arthropods may lead to development novel biorational insecticides. Extracts of Alternaria tenuissima MFP253011 obtained by various methods showed a wide range of biological activity, including entomotoxic properties. Analysis of their composition and bioactivity allowed to reveal several known mycotoxins and unidentified compounds that may be involved in entomotoxic activity of the extracts. Among them, tenuazonic acid (TeA), which was the major component of the A. tenuissima extracts, was found the most likely to have larvicidal activity against Galleria mellonella. In the intrahaemocoel injection bioassay, TeA was toxic to G. mellonella and of Zophobas morio with LT50 6 and 2 days, respectively, at the level of 50 µg/larva. Administered orally, TeA inhibited growth of G. mellonella larvae and caused mortality of Acheta domesticus imagines (LT50 7 days) at a concentration of 250 µg/g of feed. TeA showed weak contact-intestinal activity against the two phytophages, Tetranychus urticae and Schizaphis graminum, causing the 12 and 40% of mortality at a concentration of 1 mg/mL. TeA was cytotoxic to Sf9 cell line (IC50 25 µg/mL). Thus, model insect G. mellonella and cell line Sf9 could be used for a further toxicological characterization of TeA.


2020 ◽  
pp. 004051752092551
Author(s):  
Javeed A Awan ◽  
Saif Ur Rehman ◽  
Muhammad Kashif Bangash ◽  
Fiaz Hussain ◽  
Jean-Noël Jaubert

Curcumin is a naturally occurring hydrophobic polyphenol compound. It exhibits a wide range of biological activities such as antibacterial, anti-inflammatory, anti-carcinogenic, antifungal, anti-HIV, and antimicrobial activity. In this research work, antimicrobial curcumin nanofibrous membranes are produce by an electrospinning technique using the Eudragit RS 100 (C19H34ClNO6) polymer solution enriched with curcumin. The morphology and chemistry of the membrane are analyzed using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Kirby Bauer disk diffusion tests are carried out to examine the antibacterial effectiveness of the membrane. Experimental results show that the nanofibers produced are of uniform thickness morphology and curcumin is successfully incorporated into the nanofibrous mat, while no chemical bonding was observed between curcumin and the polymer. The antimicrobial curcumin nanofibrous membranes can be effectively applied as antimicrobial barrier in a wide variety of medical applications such as wound healing, scaffolds, and tissue engineering.


Author(s):  
Nieves Baenas ◽  
Jenny Ruales ◽  
Diego A. Moreno ◽  
Daniel Alejandro Barrio ◽  
Carla M. Stinco ◽  
...  

Andean blueberries are wild berries grown and consumed in Ecuador which contain high values of bioactive compounds, mainly anthocyanins, with powerful antioxidant activity. The aim of this study was to evaluate the profile and contents of (poly)phenols and carotenoids in Andean blueberry by HPLC-DAD-MSn and determine a wide range of its biological activities. The antioxidant capacity of this fruit was evaluated in vitro by three different methods and in vivo using the zebrafish animal model, also the toxicity effect was determined by the zebrafish embryogenesis test. Besides, the antimicrobial activity and the capacity of Andean blueberry to produce hemagglutination in blood cells were evaluated. Finally, the bioaccessibility of (poly)phenols and related antioxidant capacity were determined in the different phases of an in vitro digestion. The global results indicated no toxicity of Andean blueberry, weakly bacteriostatic activity, and high contents of anthocyanins and antioxidant capacity, which were partially bioaccesible in vitro (~ 50 % at the final intestinal step), contributing to the knowledge of its health benefits for consumers and its potential use in the food and pharmaceutical industry as functional ingredient.


2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Abdolazim Behfar ◽  
Narges Aqajari ◽  
Mohammad Reza Shushizadeh ◽  
Zahra Ramezani ◽  
Ebrahim Rajabzadeh Ghatrami

Background: Brown seaweeds contain polysaccharides, minerals, proteins, pigments, polyphenols, and fatty acids. Several of these compounds show a wide range of biological activities, such as anticoagulant, anti-tumor, antiviral, and anti-cancer effects. Objectives: This study was designed to evaluate the extraction, purification, and characterization of alginate from Sargassum angustifolium simultaneous with fucoidan extraction and the effect of this process on the structure and properties of alginate. Methods: The extraction of alginate from S. angustifolium was carried out using defatting with organic solvents mixture, treatment with acid-base solutions, and purification with absolute ethanol. The novel characterization of this compound was carried out by the Fourier transform infrared spectroscopy (FT-IR), FT-NMR, energy dispersive X-ray (EDX), and florescent spectrophotometry methods. Results: The fluorescent emission of alginate showed 66.54% removal of impurities, such as phenolic compounds. The FT-IR analysis showed the carboxyl and hydroxyl groups as significant signals in the alginate structure. By analyzing the anomeric protons and other aspects of 1H-NMR, M/G ratio, FG, FM, FGG, FMM, FMG (or FGM) were determined to be 0.61, 0.62, 0.38, 0.31, 0.07, and 0.31, respectively. The intrinsic viscosity and molecular weight of alginate were 0.9 dL/g and 41.53 kDa, respectively. Conclusions: The total amount of alginate from the residual S. angustifolium was 17% of dried seaweed. The structure elucidation of alginate was performed with the FT-IR, FT-NMR, and EDX methods.


2021 ◽  
Author(s):  
Marina Kostić ◽  
◽  
Vera Divac ◽  
Sven Mangelinckx

The discovery that palladium complexes possess a wide range of biological activities (from antitumor, -viral, -malarial, -fungal to antimicrobial activities) encourages further research in this scientific field. Herein we describe the synthesis and characterization of a novel palladium (II) complex, using [Pd(dien)Cl]Cl and 2-(azidomethyl)cyclopropane-1,1-dicarboxylic acid (azmcpda) as a ligand. [Pd(dien)Cl]Cl was selected as a starting material taking into consideration its importance as a model for the investigation of the substitution reactions in coordination chemistry and a deeper understanding of the biological activities of some structurally similar compounds. The ligand compound was synthesized by the procedure described in the literature. It is noteworthy to mention that 2- (azidomethyl)cyclopropane-1,1-dicarboxylic acid presents the precursor for the synthesis of 2- (aminomethyl)cyclopropane-1,1-dicarboxylic acid, as an example of the constrained γ-amino dicarboxylic acids. The synthesis was achieved by the conversion of the ligand compound into the corresponding sodium dicarboxylate salt and subsequent treatment with [Pd(dien)Cl]Cl (pH maintained between 6-7). The IR and NMR spectra, as well as elemental analysis have confirmed that the Na[Pd(dien)(azmcpda)]. H2O species was formed and that coordination of the ligand compound to the metal ion was established through carboxylate oxygen donor atom.


Marine Drugs ◽  
2020 ◽  
Vol 18 (6) ◽  
pp. 326
Author(s):  
Dawrin Pech-Puch ◽  
Mar Pérez-Povedano ◽  
Marta Martinez-Guitian ◽  
Cristina Lasarte-Monterrubio ◽  
Juan Carlos Vázquez-Ucha ◽  
...  

The pyrrole-imidazoles, a group of alkaloids commonly found in marine sponges belonging to the genus Agelas, display a wide range of biological activities. Herein, we report the first chemical study of the secondary metabolites of the sponge A. dilatata from the coastal area of the Yucatan Peninsula (Mexico). In this study, we isolated eight known alkaloids from an organic extract of the sponge. We used NMR and MS analysis and comparison with existing databases to characterize the alkaloids: ageliferin (1), bromoageliferin (2), dibromoageliferin (3), sceptrin (4), nakamuric acid (5), 4-bromo-1H-pyrrole-2-carboxylic acid (6), 4,5-dibromopyrrole-2-carboxylic acid (7) and 3,7-dimethylisoguanine (8). We also evaluated, for the first time, the activity of these alkaloids against the most problematic multidrug-resistant (MDR) pathogens, i.e., the Gram-negative bacteria Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii. Bromoageliferin (2) displayed significant activity against P. aeruginosa. Comparison of the antibacterial activity of ageliferins 1–3 (of similar structure) against P. aeruginosa revealed some relationship between structure and activity. Furthermore, in in vitro assays, 2 inhibited growth and biofilm production in clinical strains of P. aeruginosa. Moreover, 2 increased the survival time in an in vivo Galleria mellonella model of infection. The findings confirm bromoageliferin (2) as a potential lead for designing new antibacterial drugs.


2012 ◽  
Vol 178-181 ◽  
pp. 1004-1007
Author(s):  
Xiu Bo Liu ◽  
Yan Shu Jia ◽  
Na Li ◽  
He Gong ◽  
Yan He Zhang ◽  
...  

The function of secondary metabolites has been a subject of debate since the first isolation and characterization of these often times structurally complex chemical compounds. By definition, secondary metabolites are naturally produced compounds that are not essential for the survival of the producing organism, as opposed to primary metabolites. Bioassays have revealed a wide range of biological activities, such as cytotoxicity, ichthyotoxicity, antimicrobial and antifeedant activity, antifoulant and anti-cancer activities. However, some of these activities are manifested against organisms that do not represent logical targets, since they would never be encountered by the producing organism in their natural habitat.


2017 ◽  
Vol 85 (9) ◽  
Author(s):  
Grant Mills ◽  
Amy Dumigan ◽  
Timothy Kidd ◽  
Laura Hobley ◽  
José A. Bengoechea

ABSTRACT Klebsiella pneumoniae causes a wide range of infections, from urinary tract infections to pneumonia. The lipopolysaccharide is a virulence factor of this pathogen, although there are gaps in our understanding of its biosynthesis. Here we report on the characterization of K. pneumoniae lpxL, which encodes one of the enzymes responsible for the late secondary acylation of immature lipid A molecules. Analysis of the available K. pneumoniae genomes revealed that this pathogen's genome encodes two orthologues of Escherichia coli LpxL. Using genetic methods and mass spectrometry, we demonstrate that LpxL1 catalyzes the addition of laureate and LpxL2 catalyzes the addition of myristate. Both enzymes acylated E. coli lipid A, whereas only LpxL2 mediated K. pneumoniae lipid A acylation. We show that LpxL1 is negatively regulated by the two-component system PhoPQ. The lipid A produced by the lpxL2 mutant lacked the 2-hydroxymyristate, palmitate, and 4-aminoarabinose decorations found in the lipid A synthesized by the wild type. The lack of 2-hydroxymyristate was expected since LpxO modifies the myristate transferred by LpxL2 to the lipid A. The absence of the other two decorations is most likely caused by the downregulation of phoPQ and pmrAB expression. LpxL2-dependent lipid A acylation protects Klebsiella from polymyxins, mediates resistance to phagocytosis, limits the activation of inflammatory responses by macrophages, and is required for pathogen survival in the wax moth (Galleria mellonella). Our findings indicate that the LpxL2 contribution to virulence is dependent on LpxO-mediated hydroxylation of the LpxL2-transferred myristate. Our studies suggest that LpxL2 might be a candidate target in the development of anti-K. pneumoniae drugs.


2020 ◽  
Vol 8 (9) ◽  
pp. 638
Author(s):  
Patrizia Pagliara ◽  
Amilcare Barca ◽  
Tiziano Verri ◽  
Carmela Caroppo

Marine cyanobacteria are a source of bioactive natural compounds, with a wide range of biotechnological applications. However, information on sponge-associated cyanobacteria are relatively scarce to date. In this paper, we carried out the morphological and molecular characterization of eight cyanobacterial strains, previously isolated from the Mediterranean sponge Petrosia ficiformis, and evaluated their biological activities on epithelial- and neuron-like cultured cells of human and murine origin. The new analysis allowed maintaining the assignment of three strains (Cyanobium sp., Leptolyngbya ectocarpi, and Synechococcus sp.), while two strains previously identified as Synechococcus sp. and Leptolyngbya sp. were assigned to Pseudanabaena spp. One strain, i.e., ITAC104, and the ITAC101 strain corresponding to Halomicronema metazoicum, shared extremely high sequence identity, practically representing two clones of the same species. Finally, for only one strain, i.e., ITAC105, assignment to a specific genus was not possible. Concerning bioactivity analyses, incubation of cyanobacterial aqueous cell supernatants induced variable responses in cultured cells, depending on cell type, with some of them showing toxic activity on human epithelial-like cells and no toxic effects on human and rat neuron-like cells. Future investigations will allow to better define the bioactive properties of these cyanobacteria strains and to understand if they can be useful for (a) therapeutic purpose(s).


Metabolites ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 444
Author(s):  
Téo Hebra ◽  
Nicolas Elie ◽  
Salomé Poyer ◽  
Elsa Van Elslande ◽  
David Touboul ◽  
...  

Microorganisms associated with termites are an original resource for identifying new chemical scaffolds or active metabolites. A molecular network was generated from a collection of strain extracts analyzed by liquid chromatography coupled to tandem high-resolution mass spectrometry, a molecular network was generated, and activities against the human pathogens methicillin-resistant Staphylococcus aureus, Candida albicans and Trichophyton rubrum were mapped, leading to the selection of a single active extract of Penicillium sclerotiorum SNB-CN111. This fungal species is known to produce azaphilones, a colorful family of polyketides with a wide range of biological activities and economic interests in the food industry. By exploring the molecular network data, it was shown that the chemical diversity related to the P. sclerotiorum metabolome largely exceeded the data already reported in the literature. According to the described fragmentation pathways of protonated azaphilones, the annotation of 74 azaphilones was proposed, including 49 never isolated or synthesized thus far. Our hypothesis was validated by the isolation and characterization of eight azaphilones, among which three new azaphilones were chlorogeumasnol (63), peniazaphilone E (74) and 7-deacetylisochromophilone VI (80).


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