Evaluation of the Antibacterial Activity of Crude Extracts Obtained From Cultivation of Native Endophytic Fungi Belonging to a Tropical Montane Rainforest in Colombia

Bioactive secondary metabolite production from endophytic fungi has gained a recurring research focus in recent decades as these microorganisms represent an unexplored biological niche for their diverse biotechnological potential. Despite this focus, studies involving tropical endophytes remain scarce, particularly those isolated from medicinal plants of these ecosystems. In addition, the state of the art of the pharmaceutical industry has experienced stagnation in the past 30years, which has pushed pathogenic infections to get one step ahead, resulting in the development of resistance to existing treatments. Here, five fungal endophytes were isolated from the medicinal plant Otoba gracilipes (Myristicaceae), which corresponded to the genera Xylaria and Diaporthe, and screened to demonstrate the promissory potential of these microorganisms for producing bioactive secondary metabolites with broad-spectrum antibacterial activities. Thus, the evaluation of crude organic extracts obtained from the mycelia and exhaust medium allowed the elucidation of Xylaria sp. and Diaporthe endophytica potential toward providing crude extracellular extracts with promising bioactivities against reference strains of Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923), according to the determined half-maximum inhibitory concentration (IC50) with values down to 3.91 and 10.50mg/ml against each pathogen, respectively. Follow-up studies provided insights into the polarity nature of bioactive compounds in the crude extracts through bioactivity guided fractionation using a polymeric resin absorbent alternative extraction procedure. In addition, evaluation of the co-culturing methods demonstrated how this strategy can enhance endophytes biosynthetic capacity and improve their antibacterial potential with a 10-fold decrease in the IC50 values against both pathogens compared to the obtained values in the preliminary evaluations of Xylaria sp. and D. endophytica crude extracts. These results support the potential of Colombian native biodiversity to provide new approaches concerning the global emergence of antibiotics resistance and future production of undiscovered compounds different from the currently used antibiotics classes and simultaneously call for the value of preserving native habitats due to their promising ecosystemic applications in the biotechnological and pharmaceutical industries.

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Isolation and antimicrobial effects of endophytic fungi from Edgeworthia chrysantha

Bangladesh Journal of Pharmacology ◽

10.3329/bjp.v10i3.23575 ◽

2015 ◽

Vol 10 (3) ◽

pp. 529 ◽

Cited By ~ 4

Author(s):

Huawei Zhang ◽

Chuanfeng Ruan ◽

Xuelian Bai

Keyword(s):

Ethyl Acetate ◽

Endophytic Fungi ◽

Fermentation Broth ◽

Fungal Endophytes ◽

Antimicrobial Effect ◽

Antibacterial Activities ◽

Antimicrobial Activities ◽

Human Pathogens ◽

Antimicrobial Effects ◽

Staphyloccocus Aureus

Ten fungal strains isolated from Edgeworthia chrysantha, one of traditional medicinal plants in China, were evaluated their antimicrobial activities against three human pathogens, Escherichia coli, Staphyloccocus aureus and Candida albicans, and two phytopathogens, Rhizoctonia cerealis and Colletotrichum gloeosporioides. The results indicated that most ethyl acetate extracts of fermentation broth of these fungal endophytes had stronger antimicrobial activities than their fermentation broth. Among these endophytic strains, both fermentation broth and the ethyl acetate extract of strain D showed the strongest inhibitory effects on all pathogens. Strains 5-19 and BZ also exhibited potent antibacterial activities. However, other strains had weak or no antimicrobial effect. This was the first report on the isolation and antimicrobial effects of endophytic fungi from E. chrysantha.

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Production of eugenol from fungal endophytesNeopestalotiopsissp. andDiaporthesp. isolated fromCinnamomum loureiroileaves

PeerJ ◽

10.7717/peerj.6427 ◽

2019 ◽

Vol 7 ◽

pp. e6427 ◽

Cited By ~ 5

Author(s):

Chutima Tanapichatsakul ◽

Sarunpron Khruengsai ◽

Sakon Monggoot ◽

Patcharee Pripdeevech

Keyword(s):

Antimicrobial Activity ◽

Antioxidant Activity ◽

Endophytic Fungi ◽

Antioxidant Activities ◽

Chemical Constituents ◽

Fungal Endophytes ◽

Biologically Active ◽

Crude Extracts ◽

Antioxidant Agents ◽

Fungal Extracts

Endophytic fungi, which colonize within a host plant without causing any apparent diseases, have been considered as an important source of bioactive secondary metabolites containing antimicrobial and antioxidant activities. The aim of this research was to isolate the endophytic fungi ofCinnamomum loureiroiand then to screen their antimicrobial and antioxidant activities. A total of 11 fungal endophytes were isolated from healthy leaves ofCinnamomum loureiroibelonging to six genera:Botryosphaeria,Colletotrichum,Diaporthe,Fusarium,Neopestalotiopsis, andPestalotiopsis. All isolated strains were cultured and further extracted with ethyl acetate solvent. Antimicrobial activity of all crude endophytic fungal extracts was analyzed using disc diffusion assay against six bacterial and two fungal pathogens. Crude extracts of strains MFLUCC15-1130 and MFLUCC15-1131 showed broad-spectrum antimicrobial activity against all tested pathogens. Activity againstBacillus cereusandStaphylococcus epidermidiswas notable, showing the lowest minimum inhibitory concentration at 3.91 μg/mL. Antioxidant activity of all crude endophytic fungal extracts was also evaluated based on 2,2-diphenyl-1-picrylhydrazyl assay. Significant antioxidant activity was detected in the crude extracts of fungus MFLUCC15-1130 and MFLUCC15-1131 with IC50of 22.92 ± 0.67 and 37.61 ± 0.49 μg/mL, respectively. Using molecular identification, MFLUCC15-1130 and MFLUCC15-1131 were identified asNeopestalotiopsissp. andDiaporthesp., respectively. The major chemical constituents produced by both crude extracts were identified by gas chromatography-mass spectrometry. Eugenol, myristaldehyde, lauric acid, and caprylic acid were the primary antimicrobial and antioxidant compounds in both crude extracts. This is the first report of eugenol being a biologically active compound ofNeopestalotiopsissp. andDiaporthesp. fungal endophytes. Eugenol has been reported as antimicrobial and antioxidant agents with agronomic applications. Thus the two newly-isolated endophytes may be used for eugenol production, which in turn can be used in a variety of applications.

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Production of Extracellular Enzymes, Antimicrobial and other Agriculturally Important Metabolites by Fungal Endophytes of Litsea glutinosa (Lour.) C.B.Rob. a Medicinal Plant

Journal of Pure and Applied Microbiology ◽

10.22207/jpam.15.4.56 ◽

2021 ◽

Author(s):

Abhinesh Madasi ◽

Aruna Ajmeera ◽

Gudepu Renuka ◽

Bhavani Vemireddy ◽

Krishna Reddy Vanteru

Keyword(s):

Medicinal Plant ◽

Root Growth ◽

Endophytic Fungi ◽

Fungal Endophytes ◽

Trichoderma Viride ◽

Hydrolytic Enzymes ◽

Enhancement Effect ◽

Antifungal Metabolites ◽

Crude Extracts ◽

Litsea Glutinosa

The present paper deals with the endophytic fungi of Litsea glutinosa, a medicinal plant highly valued in Ayurvedic system. A total of 21 fungal endophytes were extracted from different parts of the plant. The following eight species viz, Aspergillus oryzae, A. terreus, Curvularia sp, Fusarium oxysporum, Gliocladium solani, Penicillium citrinum, Trichoderma viride and Verticillium dahliae were selected for testing the production of secondary metabolites including hydrolytic enzymes. All the eight endophytic fungal species produced amylase, cellulase, protease and lipase. Except for Curvularia species, others did not elaborate laccase. All the test fungi produced antibacterial and antifungal metabolites; however, the crude extracts exhibited poor antimicrobial activity. The present endophytic fungi also produced IAA, ammonia and phosphate solubilizing substances. They were also capable to produce IAA with or without adding the tryptophan. An affect was also made to assess the influence of crude extracts on the root growth of maize seedlings. These studies revealed the enhancement effect of extracts on root growth. Based on these observations, discussions and conclusions were made.

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Antibacterial activity of endophytic fungi from some medicinal plants of Biligirirangana hill, India

Journal of Applied and Natural Science ◽

10.31018/jans.v10i4.1923 ◽

2018 ◽

Vol 10 (4) ◽

pp. 1286-1290

Author(s):

Sushma K.S ◽

Jayashankar M. ◽

Mohammed Ali Saeed ◽

Vinu A.K.

Keyword(s):

Antibacterial Activity ◽

Medicinal Plants ◽

Endophytic Fungi ◽

Fungal Endophytes ◽

Inhibition Zone ◽

Phytochemical Analysis ◽

Crude Extracts ◽

Aspergillus Sp ◽

And Staphylococcus Aureus ◽

Positive Results

Twenty fungal endophytes were isolated from different medicinal plants of Biligirirangana Hill, Chamarajanagar dist. Phytochemical analysis of ethyl acetate extract showed positive results for tanins, flavonoids, steroids, terpenoids, glycosides, saponins and alkaloids except saponin and flavonoid tests. The crude extracts of the fungal endophytes were tested against two gram positive and two gramnegetive bacteria for its antibacterial activity. The highest zone of inhibition was produced by Fusarium sps (AB9)35mm. All the crude extracts were found to be effective against Escherichia coli, Bacillus subtilis and Staphylococcus aureus rather in Pseudomonas aerogenosa. Among them the highest inhibition zone was produced in Penicillium sp (AB11) 24mm, Cladosporium sp(AB3) 21mm, and Aspergillus sp(AB12) 30mm. Therefore, endophytic fungi can be a good source to inhibit the growth of harmful pathogens.

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Biodiversity, Ecology, and Secondary Metabolites Production of Endophytic Fungi Associated with Amaryllidaceae Crops

Agriculture ◽

10.3390/agriculture10110533 ◽

2020 ◽

Vol 10 (11) ◽

pp. 533 ◽

Cited By ~ 1

Author(s):

Gianluca Caruso ◽

Nadezhda Golubkina ◽

Alessio Tallarita ◽

Magdi T. Abdelhamid ◽

Agnieszka Sekara

Keyword(s):

Endophytic Fungi ◽

Fungal Endophytes ◽

Market Potential ◽

Plant Diseases ◽

In Vitro Synthesis ◽

Pharmaceutical Industries ◽

Fungal Microbiome ◽

Antagonistic Potential ◽

Metabolites Production

Amaryllidaceae family comprises many crops of high market potential for the food and pharmaceutical industries. Nowadays, the utilization of plants as a source of bioactive compounds requires the plant/endophytic microbiome interactions, which affect all aspects of crop’s quantity and quality. This review highlights the taxonomy, ecology, and bioactive chemicals synthesized by endophytic fungi isolated from plants of the Amaryllidaceae family with a focus on the detection of pharmaceutically valuable plant and fungi constituents. The fungal microbiome of Amaryllidaceae is species- and tissue-dependent, although dominating endophytes are ubiquitous and isolated worldwide from taxonomically different hosts. Root sections showed higher colonization as compared to bulbs and leaves through the adaptation of endophytic fungi to particular morphological and physiological conditions of the plant tissues. Fungal endophytes associated with Amaryllidaceae plants are a natural source of ecofriendly bioagents of unique activities, with special regard to those associated with Amarylloidae subfamily. The latter may be exploited as stimuli of alkaloids production in host tissues or can be used as a source of these compounds through in vitro synthesis. Endophytes also showed antagonistic potential against fungal, bacterial, and viral plant diseases and may find an application as alternatives to synthetic pesticides. Although Amaryllidaceae crops are cultivated worldwide and have great economic importance, the knowledge on their endophytic fungal communities and their biochemical potential has been neglected so far.

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Antimicrobial and Cytotoxic Potential of Crude Extracts from Culturable Fungal Endophytes Associated with the Mangrove Species Rhizophora stylosa and R. mucronata in the South China Sea

10.21203/rs.3.rs-249721/v1 ◽

2021 ◽

Author(s):

Jing Xu ◽

Jing Zhou

Keyword(s):

Cancer Cells ◽

Endophytic Fungi ◽

Pathogenic Fungus ◽

Fungal Endophytes ◽

Cytotoxic Agents ◽

Human Lung Cancer ◽

Cytotoxic Activities ◽

Rhizophora Stylosa ◽

Crude Extracts ◽

Rice Medium

Abstract Our research evaluated the antimicrobial and cytotoxic activities of crude extracts of endophytic fungi from R. stylosa and R. mucronate. 46 fungal isolates were cultured on the four different mediums, namely Dextrose Agar (PDA), Czapek’s Agar (CZA), Rice Medium (RM) and Grain Medium (GM), and harvested by ethyl acetate solvent at 40 days. The extracts were tested for antimicrobial activity by the microdilution method against Gram-negative bacteria Pseudomons adaceae (PA), Gram-positive bacteria Enterococcus faecalis (EF), Methicillin-resistant Staphylococcus aureus (MRSA) and pathogenic fungus Monilia albican (MA). Cytotoxic activity of the extracts was evaluated by MTT assay using human lung cancer cells A549, human cervical carcinoma cells Hela, and human hepatocellular cells HepG2. The results showed that rice medium could promote the secretion of antimicrobial and anti-tumor secondary metabolites of endophytic fungi in comparison with the other cultivation media. 17 strains (68%) from R. stylosa exhibited inhibition effects on indicators, especially N. protearum HHL46 which could inhibit the growth of four microbes with the MIC values reaching 0.0625 mg/mL. 15 strains (71.4%) from R. mucronata displayed activities against human pathogenic microbes, especially Pestalotiopsis sp. HQD6 and N. protearum HQD5 which could resist the growth of four microbial with MIC values ranging from 0.015 to 1 mg/mL. In cytotoxic assay, the extracts of 10 strains (40%), 9 strains (40%) and 13 strains (52%) from R. stylosa and 13 strains (61.9%), 10 stains (47.6%) and 10 stains (47.6%) in R. mucronata displayed the cytotoxicity against A549, Hela and HepG2 cancer cells with cells viability value ≤50%, respectively. Neopestalotiopsis protearum HHL46, Phomopsis longicolla HHL50, Botryosphaeria fusispora HQD83, Fusarium verticillioides HQD48 and Pestalotiopsis sp. HQD6 displayed significant antitumor activity with IC50 values below the 20 μg/mL. These results highlighted the antimicrobial and anti-tumor potential of endophytic fungi from R. stylosa and R. mucronata and the possibility to be exploited for their antimicrobial and cytotoxic agents.

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Isolation and Characterization of Fungal Endophytes Isolated from Medicinal Plant Ephedra pachyclada as Plant Growth-Promoting

Biomolecules ◽

10.3390/biom11020140 ◽

2021 ◽

Vol 11 (2) ◽

pp. 140 ◽

Cited By ~ 2

Author(s):

Ahmed Mohamed Aly Khalil ◽

Saad El-Din Hassan ◽

Sultan M. Alsharif ◽

Ahmed M. Eid ◽

Emad El-Din Ewais ◽

...

Keyword(s):

Medicinal Plants ◽

Plant Growth ◽

Aspergillus Flavus ◽

Endophytic Fungi ◽

Fungal Endophytes ◽

Penicillium Crustosum ◽

Plant Growth Promoting ◽

Penicillium Commune ◽

Maize Plants ◽

Growth Promoting

Endophytic fungi are widely present in internal plant tissues and provide different benefits to their host. Medicinal plants have unexplored diversity of functional fungal association; therefore, this study aimed to isolate endophytic fungi associated with leaves of medicinal plants Ephedra pachyclada and evaluate their plant growth-promoting properties. Fifteen isolated fungal endophytes belonging to Ascomycota, with three different genera, Penicillium, Alternaria, and Aspergillus, were obtained from healthy leaves of E. pachyclada. These fungal endophytes have varied antimicrobial activity against human pathogenic microbes and produce ammonia and indole acetic acid (IAA), in addition to their enzymatic activity. The results showed that Penicillium commune EP-5 had a maximum IAA productivity of 192.1 ± 4.04 µg mL−1 in the presence of 5 µg mL−1 tryptophan. The fungal isolates of Penicillium crustosum EP-2, Penicillium chrysogenum EP-3, and Aspergillus flavus EP-14 exhibited variable efficiency for solubilizing phosphate salts. Five representative fungal endophytes of Penicillium crustosum EP-2, Penicillium commune EP-5, Penicillium caseifulvum EP-11, Alternaria tenuissima EP-13, and Aspergillus flavus EP-14 and their consortium were selected and applied as bioinoculant to maize plants. The results showed that Penicillium commune EP-5 increased root lengths from 15.8 ± 0.8 to 22.1 ± 0.6. Moreover, the vegetative growth features of inoculated maize plants improved more than the uninoculated ones.

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The Influence of the Grapevine Bacterial and Fungal Endophytes on Biomass Accumulation and Stilbene Production by the In Vitro Cultivated Cells of Vitis amurensis Rupr.

Plants ◽

10.3390/plants10071276 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1276

Author(s):

Olga A. Aleynova ◽

Andrey R. Suprun ◽

Nikolay N. Nityagovsky ◽

Alexandra S. Dubrovina ◽

Konstantin V. Kiselev

Keyword(s):

Cell Culture ◽

Cell Suspension ◽

Endophytic Fungi ◽

Endophytic Bacteria ◽

Fungal Endophytes ◽

Biomass Accumulation ◽

Vitis Amurensis ◽

Grape Cell ◽

Stilbene Biosynthesis

Plant endophytes are known to alter the profile of secondary metabolites in plant hosts. In this study, we identified the main bacterial and fungal representatives of the wild grape Vitis amurensis Rupr. microbiome and investigated a cocultivation effect of the 14 endophytes and the V. amurensis cell suspension on biomass accumulation and stilbene biosynthesis. The cocultivation of the V. amurensis cell culture with the bacteria Agrobacterium sp., Bacillus sp., and Curtobacterium sp. for 2 weeks did not significantly affect the accumulation of cell culture fresh biomass. However, it was significantly inhibited by the bacteria Erwinia sp., Pantoea sp., Pseudomonas sp., and Xanthomonas sp. and fungi Alternaria sp., Biscogniauxia sp., Cladosporium sp., Didymella sp. 2, and Fusarium sp. Cocultivation of the grapevine cell suspension with the fungi Didymella sp. 1 and Trichoderma sp. resulted in cell death. The addition of endophytic bacteria increased the total stilbene content by 2.2–5.3 times, while the addition of endophytic fungi was more effective in inducing stilbene accumulation by 2.6–16.3 times. The highest content of stilbenes in the grapevine cells cocultured with endophytic fungi was 13.63 and 13.76 mg/g of the cell dry weight (DW) after cultivation with Biscogniauxia sp. and Didymella sp. 2, respectively. The highest content of stilbenes in the grapevine cells cocultured with endophytic bacteria was 4.49 mg/g DW after cultivation with Xanthomonas sp. The increase in stilbene production was due to a significant activation of phenylalanine ammonia lyase (PAL) and stilbene synthase (STS) gene expression. We also analyzed the sensitivity of the selected endophytes to eight antibiotics, fluconazole, and trans-resveratrol. The endophytic bacteria were sensitive to gentamicin and kanamycin, while all selected fungal strains were resistant to fluconazole with the exception of Cladosporium sp. All endophytes were tolerant of trans-resveratrol. This study showed that grape endophytes stimulate the production of stilbenes in grape cell suspension, which could further contribute to the generation of a new stimulator of stilbene biosynthesis in grapevine or grape cell cultures.

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Diversity and Antimicrobial Activity of Culturable Fungal Endophytes in Solanum mauritianum

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17020439 ◽

2020 ◽

Vol 17 (2) ◽

pp. 439 ◽

Cited By ~ 1

Author(s):

Sharon Pelo ◽

Vuyo Mavumengwana ◽

Ezekiel Green

Keyword(s):

Deoxyribonucleic Acid ◽

Fungal Endophytes ◽

Antimycobacterial Activity ◽

Great Activity ◽

Isolation And Identification ◽

Gram Positive Bacteria ◽

Crude Extracts ◽

Solanum Mauritianum ◽

Fusarium Sp ◽

Respective Host

Plant endophytes are microbial sources of bioactive secondary metabolites, which mimic the natural compounds chemistry of their respective host plants in a similar manner. This study explored the isolation and identification of fungal endophytes, and investigated the antibacterial and antimycobacterial activity of their crude extracts. Fungal endophytes were isolated from Solanum mauritianum, identified using morphological traits and internal transcribed spacer ribosomal-deoxyribonucleic acid (ITS-rDNA) sequence analysis. Eight fungal endophytes were identified as Aureobasidium pullulans, Paracamarosporium leucadendri, Cladosporium sp., Collectotrichum boninense, Fusarium sp., Hyalodendriella sp., and Talaromyces sp., while Penicillium chrysogenum was isolated from the leaves and unripe fruits. Good activity was observed for the crude extracts of Paracamarosporium leucadendri inhibiting Mycobacterium bovis, Klebsiella pneumoniae, and Pseudomonas aeruginosa at 6 µg/mL. Crude extracts of Fusarium sp., showed activity at 9 μg/mL against M. bovis, M. smegmatis and K. pneumonia. In general, the crude extracts showed great activity against Gram-negative and Gram-positive bacteria and novel results for two mycobacteria species M. bovis and M. smegmatis. The results provide evidence of diverse fungal endophytes isolated from Solanum mauritianum, and evidence that fungal endophytes are a good source of bioactive compounds with pharmaceutical potential, particularly against Mycobacterium tuberculosis.

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Revealing the endophytic mycoflora in tea (Camellia sinensis) leaves in Sri Lanka: the first comprehensive study

Phytotaxa ◽

10.11646/phytotaxa.514.3.5 ◽

2021 ◽

Vol 514 (3) ◽

pp. 247-260

Author(s):

KASUN THAMBUGALA ◽

DINUSHANI DARANAGAMA ◽

SAGARIKA KANNANGARA ◽

THENUKA KODITUWAKKU

Keyword(s):

Sri Lanka ◽

Camellia Sinensis ◽

Endophytic Fungi ◽

Sequence Data ◽

Fungal Endophytes ◽

Fungal Endophyte ◽

Tea Leaves ◽

Molecular Sequence Data ◽

Molecular Sequence ◽

Rdna Sequence Data

Endophytic fungi are a diverse group of microorganisms that live asymptomatically in healthy tissues of host and they have been reported from all kinds of plant tissues such as leaves, stems, roots, flowers, and fruits. In this study, fungal endophytes associated with tea leaves (Camellia sinensis) were collected from Kandy, Kegalle, and Nuwara Eliya districts in Sri Lanka and were isolated, characterized, and identified. A total of twenty endophytic fungal isolates belonging to five genera were recovered and ITS-rDNA sequence data were used to identify them. All isolated endophytic fungal strains belong to the phylum Ascomycota and the majority of these isolates were identified as Colletotrichum species. Phyllosticta capitalensis was the most commonly found fungal endophyte in tea leaves and was recorded in all three districts where the samples were collected. This is the very first investigation on fungal endophytes associated with C. sinensis in Sri Lanka based on molecular sequence data. In addition, a comprehensive account of known endophytic fungi reported worldwide on Camellia sinensis is provided.

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