Inhibition of symbiote fungus of the leaf cutter ant Atta sexdens by secondary metabolites from the bacterium Xenorhabdus szentirmaii associated with entomopathogenic nematodes

ABSTRACT: Leaf-cutter ants (Hymenoptera: Formicidae) have evolved as dominant herbivores on the American continent. These social insects remove the leaves of economically important plant species to maintain their colony’s food reserves, the symbiotic fungus Leucocoprinus gongylophorus, a basidiomycete. Such fungus can be used for applications of fungicide molecules from metabolites generated by symbiont bacteria (Xenorhabdus and Photorhabdus) from entomopathogenic nematodes (Steinernema and Heterorhabditis). Through isolation and multiplication in tryptic soy broth (TSB) medium of the bacteria Xenorhabdus szentirmaii isolated PAM 25, we conducted laboratorial tests using treatments with 10, 25, and 50% of the metabolites obtained in the sixth day of cultivation. The treatments were centrifuged and filtered to generate a supernatant, which was diluted in potato + dextrose + agar (PDA), to verify the consequences of exposure to the fungus L. gongylophorus in Petri dishes. To confirm metabolite efficiency, the control treatments in PDA only and mixed (PDA+TSB) media were conducted simultaneously for 14 days. We observed total inhibition of the symbiont fungus in both the 25 and 50% dilutions during the first days of the tests. Our results support that these metabolites have inhibitory effect on the development of symbiont fungus of leaf-cutter ants.

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Fungal Tolerance: An Alternative for the Selection of Fungi with Potential for the Biological Recovery of Precious Metals

Applied Sciences ◽

10.3390/app10228096 ◽

2020 ◽

Vol 10 (22) ◽

pp. 8096

Author(s):

Rosalba Argumedo-Delira ◽

Mario J. Gómez-Martínez ◽

Ramiro Uribe-Kaffure

Keyword(s):

Filamentous Fungi ◽

Precious Metals ◽

Inhibitory Effect ◽

Potato Dextrose Agar ◽

Simple Test ◽

Biotechnological Applications ◽

Secondary Sources ◽

Fungal Tolerance ◽

Petri Dishes ◽

Selection Of

The behavior of various filamentous fungi in the presence of metals such as Cu, Zn, Ni, Fe, Mn, and V has been widely reported. However, there is little information regarding metals such as Au, Ag and Pt that are not in the form of nanoparticles. The growth of eight filamentous fungi was evaluated at increasing doses of Au, Ag and Pt. The fungi were reactivated in Petri dishes with potato dextrose agar. Subsequently, individual mycelial disks from each strain were inoculated in PDA plates with the following doses of AuCl3, Ag2SO4 and PtCl4: 0, 50, 150 and 300 mg L−1, respectively. The plates were then incubated for 20 days—a period in which the diameter of the colony was measured every 24 h. Au showed the highest toxicity for the tested fungi. All silver doses decreased the growth of most of the fungi, while platinum did not cause any inhibitory effect on the growth of the eight tested fungi. With a simple test, it was possible to observe the effect of precious metals (PMs) on the growth of filamentous fungi and consider their possible biotechnological applications in the recovery of PMs from primary or secondary sources.

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Activity of sesame leaf extracts against the symbiotic fungus of Atta sexdens L.

Anais da Sociedade Entomológica do Brasil ◽

10.1590/s0301-80591998000300010 ◽

1998 ◽

Vol 27 (3) ◽

pp. 421-426 ◽

Cited By ~ 9

Author(s):

Stelamaris B. Ribeiro ◽

Fernando C. Pagnocca ◽

Sandra R. Victor ◽

Odair C. Bueno ◽

Maria J. Hebling ◽

...

Keyword(s):

Leaf Tissue ◽

Inhibitory Effect ◽

Sesamum Indicum ◽

Atta Sexdens ◽

Leaf Extracts ◽

Symbiotic Fungus ◽

Single Substance ◽

Total Inhibition ◽

Leaf Cutting ◽

Leucoagaricus Gongylophorus

The symbiotic fungus Leucoagaricus gongylophorus (Möller) Singer (syn. Rozites gongylophora Möller) cultivated by the leaf-cutting ant Atta sexdens L. had its development strongly inhibited by crude extracts obtained from leaves of sesame, Sesamum indicum L. (Pedaliaceae). With most of the fractions from these extracts total inhibition was observed at 2.5 mg/ml, whereas inhibition of 50% was observed with some fractions at 1.25 mg/ml. Chromatographic analysis of the hexane extract showed that it was composed by a mixture of fatty acids, of which tetradecanoic, hexadecanoic, octadecanoic, icosanoic, docosanoic and 9,12,15 octadecatrienoic acids were the major components. The separation of these compounds during the different steps of purification resulted in no or lower inhibitory effect for most of these fractions, indicating that the inhibitory activity observed could be due to the joint action of these compounds present in the leaf tissue, rather than to the action of a single substance.

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Secondary Metabolites from Saccharomyces cerevisiae Species with Anticancer Potential

10.5772/intechopen.95067 ◽

2021 ◽

Author(s):

Muhammad Jahangeer ◽

Areej Riasat ◽

Zahed Mahmood ◽

Muhammad Numan ◽

Naveed Munir ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Secondary Metabolites ◽

Apoptotic Cell ◽

Inhibitory Effect ◽

Chemotherapeutic Agents ◽

Chemotherapeutic Drugs ◽

Central Metabolism ◽

Biotic Stresses ◽

Micro Organisms ◽

New Chemotherapeutic Agents

Chemotherapeutic agents produce from numerous sources such as animals, plants and micro-organisms are derived from the natural products. Although the existing therapeutic pipeline lacks fungal-derived metabolites, but hundreds of secondary metabolites derived from fungi are known to be possible chemotherapies. Over the past three decades, several secondary metabolites such as flavonoids, alkaloids, phenolic and polyketides have been developed by Saccharomyces cerevisiae species with exciting activities that considered valued for the growth of new chemotherapeutic agents. Many secondary metabolites are protective compounds which prevent abiotic and biotic stresses, i.e. predation, infection, drought and ultraviolet. Though not taking part in a living cell’s central metabolism, secondary metabolites play an important role in the function of an organism. Nevertheless, due to slow biomass build-up and inadequate synthesis by the natural host the yield of secondary metabolites is low by direct isolation. A detailed comprehension of biosynthetic pathways for development of secondary metabolites are necessary for S. cerevisiae biotransformation. These metabolites have higher inhibitory effect, specificity among cancer and normal cells, and the mechanism of non-apoptotic cell killing. This study shows the significance of bioactive compounds produced by S. cerevisiae species with their possible activity and value in chemotherapeutic drugs pipeline. The isolation and alteration of these natural secondary metabolites would promote the development of chemotherapeutic drugs.

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Hormone control in regeneration: effects of somatostatin on appendage regeneration, blood glucose and liver glycogen in Diemictylus viridescens

Development ◽

10.1242/dev.40.1.115 ◽

1977 ◽

Vol 40 (1) ◽

pp. 115-124

Author(s):

S. Vethamany-Globus ◽

M. Globus ◽

J. A. Hartford ◽

I. Fraser ◽

D. Weber

Keyword(s):

Blood Glucose ◽

Liver Glycogen ◽

Inhibitory Effect ◽

Thyroid Stimulating Hormone ◽

Present Communication ◽

Tail Regeneration ◽

Experimental Animals ◽

Total Inhibition ◽

Daily Dose ◽

Hormone Control

In the present communication, synthetic somatostatin, a hypothalamic factor which has a known inhibitory effect on the release of growth hormone, thyroid-stimulating hormone, prolactin, insulin and glucagon in man and other mammals, was found to have an inhibitory effect on limb and tail regeneration in adult Diemictylus viridescens, when the newts were treated with a daily dose of 3·5 or 15 µg/animal for a period of 34 days post-amputation. At the higher dose, the animals exhibited total inhibition of appendage regeneration in a few cases and the remainder showed a considerable delay compared to the controls; none of the experimental animals reached the advanced four-digit stage achieved by the controls. Furthermore, the blood glucose and liver glycogen values in the somatostatin-treated animals were significantly lower than the control values. Mechanisms in the storage, mobilization and utilization of glucose (involving hormones) are discussed in relation to appendage regeneration in the newt and possible controls of regeneration at the level of the hypothalamus are suggested.

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Dissemination of Isaria fumosorosea Spores by Steinernema feltiae and Heterorhabditis bacteriophora

Journal of Fungi ◽

10.3390/jof6040359 ◽

2020 ◽

Vol 6 (4) ◽

pp. 359

Author(s):

Jiří Nermuť ◽

Jana Konopická ◽

Rostislav Zemek ◽

Michal Kopačka ◽

Andrea Bohatá ◽

...

Keyword(s):

Entomopathogenic Nematodes ◽

Heterorhabditis Bacteriophora ◽

Potato Dextrose Agar ◽

Steinernema Feltiae ◽

Soil Organisms ◽

Isaria Fumosorosea ◽

Second Stage ◽

Glass Tubes ◽

First Time ◽

Globally Distributed

Entomopathogenic nematodes and fungi are globally distributed soil organisms that are frequently used as bioagents in biological control and integrated pest management. Many studies have demonstrated that the combination of biocontrol agents can increase their efficacy against target hosts. In our study, we focused on another potential benefit of the synergy of two species of nematodes, Steinernema feltiae and Heterorhabditis bacteriophora, and the fungus Isaria fumosorosea. According to our hypothesis, these nematodes may be able to disseminate this fungus into the environment. To test this hypothesis, we studied fungal dispersal by the nematodes in different arenas, including potato dextrose agar (PDA) plates, sand heaps, sand barriers, and glass tubes filled with soil. The results of our study showed, for the first time, that the spreading of both conidia and blastospores of I. fumosorosea is significantly enhanced by the presence of entomopathogenic nematodes, but the efficacy of dissemination is negatively influenced by the heterogeneity of the testing arena. We also found that H. bacteriophora spread fungi more effectively than S. feltiae. This phenomenon could be explained by the differences in the presence and persistence of second-stage cuticles or by different foraging behavior. Finally, we observed that blastospores are disseminated more effectively than conidia, which might be due to the different adherence of these spores (conidia are hydrophobic, while blastospores are hydrophilic). The obtained results showed that entomopathogenic nematodes (EPNs) can enhance the efficiency of fungal dispersal.

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Pubinernoid A and Apo-9′-fucoxanthinone, Secondary Metabolites from a Gorgonian Coral Pinnigorgia sp

Natural Product Communications ◽

10.1177/1934578x1601100601 ◽

2016 ◽

Vol 11 (6) ◽

pp. 1934578X1601100

Author(s):

Hsin-Huan Chang ◽

Yu-Chia Chang ◽

Wu-Fu Chen ◽

Tsong-Long Hwang ◽

Lee-Shing Fang ◽

...

Keyword(s):

Secondary Metabolites ◽

Spectroscopic Data ◽

Spectroscopic Analysis ◽

Inhibitory Effect ◽

Human Neutrophils ◽

Gorgonian Coral ◽

First Report ◽

Significant Inhibitory Effect ◽

Animal Source

The structures of pubinernoid A (1) and apo-9′-fucoxanthinone (2), isolated from a gorgonian coral Pinnigorgia sp., were elucidated on the basis of spectroscopic analysis and by comparison of their spectroscopic data with those of known compounds. This is the first report of 1 and 2 from an animal source. Apo-9′-fucoxanthinone (2) displayed a significant inhibitory effect on the release of elastase by human neutrophils, with an IC50 value of 5.75 μM.

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Bacteria from the Midgut of Common Cockchafer (Melolontha melolontha L.) Larvae Exhibiting Antagonistic Activity Against Bacterial Symbionts of Entomopathogenic Nematodes: Isolation and Molecular Identification

International Journal of Molecular Sciences ◽

10.3390/ijms21020580 ◽

2020 ◽

Vol 21 (2) ◽

pp. 580 ◽

Cited By ~ 2

Author(s):

Marcin Skowronek ◽

Ewa Sajnaga ◽

Małgorzata Pleszczyńska ◽

Waldemar Kazimierczak ◽

Magdalena Lis ◽

...

Keyword(s):

Gut Microbiota ◽

Entomopathogenic Nematodes ◽

Insect Pests ◽

Entomopathogenic Nematode ◽

Acinetobacter Calcoaceticus ◽

Inhibitory Effect ◽

Antagonistic Activity ◽

Reca Gene ◽

Melolontha Melolontha ◽

Insect Gut

The mechanisms of action of the complex including entomopathogenic nematodes of the genera Steinernema and Heterorhabditis and their mutualistic partners, i.e., bacteria Xenorhabdus and Photorhabdus, have been well explained, and the nematodes have been commercialized as biological control agents against many soil insect pests. However, little is known regarding the nature of the relationships between these bacteria and the gut microbiota of infected insects. In the present study, 900 bacterial isolates that were obtained from the midgut samples of Melolontha melolontha larvae were screened for their antagonistic activity against the selected species of the genera Xenorhabdus and Photorhabdus. Twelve strains exhibited significant antibacterial activity in the applied tests. They were identified based on 16S rRNA and rpoB, rpoD, or recA gene sequences as Pseudomonas chlororaphis, Citrobacter murliniae, Acinetobacter calcoaceticus, Chryseobacterium lathyri, Chryseobacterium sp., Serratia liquefaciens, and Serratia sp. The culture filtrate of the isolate P. chlororaphis MMC3 L3 04 exerted the strongest inhibitory effect on the tested bacteria. The results of the preliminary study that are presented here, which focused on interactions between the insect gut microbiota and mutualistic bacteria of entomopathogenic nematodes, show that bacteria inhabiting the gut of insects might play a key role in insect resistance to entomopathogenic nematode pressure.

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Chemical Composition and Biological Activities of Metabolites from the Marine Fungi Penicillium sp. Isolated from Sediments of Co To Island, Vietnam

Molecules ◽

10.3390/molecules24213830 ◽

2019 ◽

Vol 24 (21) ◽

pp. 3830

Author(s):

Hong Le ◽

Quynh Do ◽

Mai Doan ◽

Quyen Vu ◽

Mai Nguyen ◽

...

Keyword(s):

Minimum Inhibitory Concentration ◽

Secondary Metabolites ◽

Inhibitory Concentration ◽

Biological Activities ◽

2D Nmr ◽

Inhibitory Effect ◽

Marine Microorganisms ◽

Penicillium Species ◽

E Coli ◽

Strong Inhibitory Effect

Marine microorganisms are an invaluable source of novel active secondary metabolites possessing various biological activities. In this study, the extraction and isolation of the marine sediment Penicillium species collected in Vietnam yielded ten secondary metabolites, including sporogen AO-1 (1), 3-indolecarbaldehyde (2), 2-[(5-methyl-1,4-dioxan-2-yl)methoxy]ethanol (3), 2-[(2R-hydroxypropanoyl)amino]benzamide (4), 4-hydroxybenzandehyde (5), chrysogine (6), 3-acetyl-4-hydroxycinnoline (7), acid 1H-indole-3-acetic (8), cyclo (Tyr-Trp) (9), and 2’,3’-dihydrosorbicillin (10). Their structures were identified by the analysis of 1D and 2D NMR data. Among the isolated compounds, 2-[(5-methyl-1,4-dioxan-2-yl)methoxy]ethanol (3) showed a strong inhibitory effect against Enterococcus faecalis with a minimum inhibitory concentration value of 32 µg/mL. Both 2-[(2R-hydroxypropanoyl)amino]benzamide (4) and 4-hydroxybenzandehyde (5) selectively inhibited E. coli with minimum inhibitory concentration values of 16 and 8 µg/mL, respectively. 2’,3’-Dihydrosorbicillin (10) potentially inhibited α-glucosidase activity at a concentration of 2.0 mM (66.31%).

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Toxicity of sesame extracts to the symbiotic fungus of leaf-cutting ants

Bulletin of Entomological Research ◽

10.1017/s0007485300050550 ◽

1990 ◽

Vol 80 (3) ◽

pp. 349-352 ◽

Cited By ~ 27

Author(s):

Fernando Carlos Pagnocca ◽

Osvaldo Aulino da Silva ◽

Maria Jose Hebling-Beraldo ◽

Odair Correa Bueno ◽

João Batista Fernandes ◽

...

Keyword(s):

Sesamum Indicum ◽

Atta Sexdens ◽

Symbiotic Fungus ◽

Atta Sexdens Rubropilosa ◽

Leaf Cutting ◽

Leucocoprinus Gongylophorus

AbstractExtracts of different sesame plant (Sesamum indicum) Linnaeus organs inhibited the in vitro growth of the fungus Leucocoprinus gongylophorus (Möller) (=Rozites gongylophora Möller), which is cultivated by the leaf-cutting ants of the species Atta sexdens rubropilosa Forel (Hymenoptera: Formicidae). The presence of the factor responsible for this inhibition was detected in methanol or chloroform extracts and is constant in the plant.

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The Influence of Sucralose on Bacterial Metabolism

Journal of Dental Research ◽

10.1177/00220345900690080601 ◽

1990 ◽

Vol 69 (8) ◽

pp. 1480-1484 ◽

Cited By ~ 14

Author(s):

D.A. Young ◽

W.H. Bowen

Keyword(s):

Agar Medium ◽

Sucrose Concentration ◽

Inhibitory Effect ◽

Oral Bacteria ◽

Streptococcus Sobrinus ◽

Streptococcus Sanguis ◽

Inhibition Of Growth ◽

Total Inhibition ◽

Glucose Agar ◽

Enzyme Ratio

Sucralose (1',4',6' trideoxy-trichloro-galactosucrose) is a nontoxic, intensely sweet sucrose derivative that has been shown to be non-cariogenic in experimental animals. The purpose of this study was to determine whether certain oral bacteria could utilize sucralose. Sucralose, as a sole carbon source, was unable to support growth of ten strains of oral bacteria and dental plaque. When sucralose was incorporated into a liquid medium containing glucose or sucrose, all organisms tested displayed similar pH falls, compared with controls. The incorporation of 126 mmol/L sucralose into glucose agar medium caused total inhibition of growth of Streptococcus sobrinus 6715-17, Streptococcus sanguis 10904, Streptococcus sanguis Challis, Streptococcus salivarius, and Actinomyces viscosus WVU627. Sucralose had no effect on IPS production. Sucralose was not bound to, nor taken up by, cells. Sucralose inhibited the formation of glucan and fructan polymers in proportion to the sucralose-to-enzyme ratio, but independent of the sucrose concentration in the assay mixture. No radioactive polymer was formed from 14C-U-sucralose added to mixtures containing glucosyltransferase (GTF) or fructosyltransferase (FTF). Inhibition of GTF and FTF by sucralose was removed following dialysis of the enzyme/sucralose mixture. These results show that sucralose was not utilized by the oral bacteria tested and that the inhibitory effect of sucralose on GTF and FTF was non-competitive and reversible. The results further support the concept that sucralose is non-cariogenic.

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