Secondary Metabolites Of Endophytic Fungi Research Articles

Antimicrobial and Cytotoxic Activities of the Secondary Metabolites of Endophytic Fungi Isolated from the Medicinal Plant Hyssopus officinalis.

According to the World Health Organization, it is estimated that by 2050, drug-resistant infections could cause up to 10 million deaths annually. Therefore, finding a new generation of antibiotics is crucial. Natural compounds from endophytic fungi are considered a potential source of new-generation antibiotics. The antimicrobial and cytotoxic effects of ethyl acetate extracts of nine endophytic fungal isolates obtained from Hyssopus officinalis were investigated for bioassay-guided isolation of the natural compounds. An extract of isolate VII showed the highest antimicrobial activities against Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus (30.12 ± 0.20 mm and 35.21 ± 0.20 mm) and Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa (30.41 ± 0.23 mm and 25.12 ± 0.25 mm) among the tested extracts of isolates. Molecular identification of isolate VII confirmed it as Chaetomium elatum based on sequencing of its ITS genes, and it was discovered that this was the first time C. elatum had been isolated from H. officinalis. This isolate was cultured at a large scale for the isolation and identification of the active compound. Penicillic acid was isolated for the first time from C. elatum and its chemical structure was established by NMR spectroscopy. The penicillic acid showed strong antibacterial activities against Bacillus subtilis and Staphylococcus aureus with 20.68 mm and 25.51 mm inhibition zones, respectively. In addition, MIC and MBC values and antibiofilm activities of penicillic acid were determined. It was found that penicillic acid reduced the level of biofilms in proportion to antibacterial activity.

Diversity of Fungal Communities on Diseased and Healthy Cinnamomum burmannii Fruits and Antibacterial Activity of Secondary Metabolites.

The composition and structure of fungal communities on healthy and diseased fruits of Cinnamomum burmannii (Nees and Nees) Blume were characterized, with evaluation of the antibacterial activity of secondary metabolites from culturable fungi following the first identification of secondary metabolites in the fungus Medicopsis romeroi (Esf-14; GenBank accession number OK242756). These results are significant for understanding the functional variation in bioactivity in fungal communities and developing a broader range of bioactive resources. High-throughput sequencing results indicated that the fungal community in diseased fruit differed from that in healthy fruit at the phylum, class, order, or genus level, with significant differences in the species and relative abundance of the dominant flora. A total of 49 (healthy fruit) and 122 (diseased fruit) artificially cultivable endophytic fungi were isolated, and 41 different strains (11 from healthy fruit and 30 from diseased fruit) were successfully identified by morphological and molecular biological analyses, which were classified into 8 groups and 23 genera by phylogenetic tree analysis, with Pleosporales, Glomerellales, and Hypocreales being the dominant groups at the order level and Colletotrichum being the dominant group at the genus level. The results of the antibacterial assay demonstrated that the secondary metabolites of all strains had different degrees of antibacterial activity, while the secondary metabolites of endophytic fungi from diseased fruit were generally stronger than those of fungi from healthy fruit, with the active secondary metabolites dominated by small and moderately polar compounds. Combined analysis of fungal communities, phylogenetic tree analysis, and bioactivity analysis of culturable strains revealed strong antibacterial activity of both upregulated and downregulated flora in diseased fruit. Five compounds, including two new (5,6-dimethoxy-[1',1:4,1″-terphenyl]-2-ol [compound 1] and 5-(methoxycarbonyl)-2-methylbenzo[d][1,3]dioxole-2-carboxylic acid [compound 2]) and three known compounds (3,7-dihydroxy-1,9-dimethyldibenzofuran [compound 3], methyl 3-hydroxybenzoate [compound 4], and uracil [compound 5]), were isolated and identified for the first time from the endophytic fungus Medicopsis romeroi. In general, the diversity of fungal communities on diseased fruit was lower than that on healthy fruits, while the antibacterial activity of artificially cultured endophytic fungi on diseased fruits was generally stronger than that on healthy fruits, suggesting excellent promise for the development of secondary metabolites from active strains on diseased fruit as antibacterial agents. IMPORTANCE Powdery fruit disease is a notorious disease of Cinnamomum burmannii that causes severe loss in fruit production. Studies on the function of endophytic fungal communities in healthy plant tissues are not new, while little is known about the functional changes of fungal communities in disease-causing plant tissues. Our results demonstrate that fungal communities in diseased fruits differ from those in healthy fruits at the level of phylum, class, order, or genus, with significant differences in the species and relative abundance of dominant groups. Endophytic fungi in diseased fruits appeared to produce secondary metabolites with stronger antibacterial properties, although the community diversity was not as varied as that in healthy fruits. In addition, secondary metabolites of the Medicopsis romeroi strain from diseased fruits were identified for the first time. These results have important implications for understanding the functional variation of bioactivity in fungal communities and for developing a broader resource of bioactivity.

Evaluating the antioxidant activity of secondary metabolites of endophytic fungi from Hypericum perforatum L. by an electrochemical biosensor based on AuNPs/AC@CS composite

Due to the variety and activity of secondary metabolites of endophytic fungi (SMEF) from medicinal plants, and the operation cumbersome of existing methods for evaluating the activity, there is urgent to establish a simple, efficient and sensitive evaluation and screening technology. In this study, the prepared chitosan functionalized activated carbon (AC@CS) composite as the electrode substrate material was used to modify glassy carbon electrode (GCE), and the gold nanoparticles (AuNPs) was deposited on AC@CS/GCE by cyclic voltammetry (CV). A ds-DNA/AuNPs/AC@CS/GCE electrochemical biosensor for evaluating the antioxidant activity of SMEF from Hypericum perforatum L. (HP L.) was fabricated using the method of layer by layer assembly. The experimental conditions affecting the evaluation results of the biosensor were optimized by square wave voltammetry (SWV) using Ru(NH3)63+ as the probe, and the antioxidant activity of various SMEF from HP L. was evaluated by the proposed biosensor. Meanwhile, the results of the biosensor were also verified by UV–vis. According to the optimized experimental results, the biosensors had a high levels of oxidative DNA damage at pH 6.0 and Fenton solution system with Fe2+ to OH− ratio of 1:3 for 30 min. Among the crude extracts of SMEF from roots, stems and leaves of HP L., the crude extracts from stems presents a high antioxidant activity, but it was weaker than l-ascorbic acid. This result was consistent with the evaluation results of UV–vis spectrophotometric method, also the fabricated biosensor presents high stability and sensitivity. This study not only provides a novel, convenient and efficient way for rapid evaluating the antioxidant activity of a wide variety of SMEF from HP L., but also provides a novel evaluation strategy for the SMEF from medicinal plants.

Endophyte Extract From Nattle (Urtica dioica L.) Against Staphylococcus aureus and Escherichia coli

Endophytes are microorganisms that colonize the plant host tissue. Endophytic colonies are able to produce secondary metabolites in accordance with their host plants, endophytes have been found in every plant species studied to date and are recognized as a source of new natural compounds that have the potential to be exploited in medicine. This study aims to isolate and obtain endophytic fungi and to test secondary metabolites that have the potential as antibacterial against Staphylococcus aureus and Escherichia coli. Plant samples were taken around the village of Mamben, Wanasaba. The research method used is experimental laboratory. This research was conducted by isolating and identifying endophytic fungi from nettle stems. Obtained a type of endophytic fungal strain using Potato Dextrose Agar (PDA) media. The production of secondary metabolites of endophytic fungi was obtained by fermentation method using brown rice for a month then macerated for 3 days using methanol solvent and tested for secondary metabolites and antibacterial activity. The endophytic fungal extract of nettle stem contains alkaloids and flavonoids and is able to inhibit the growth of Staphylococcus aureus bacteria with the highest concentration of 60% with an inhibition zone of 18 mm. whereas, the extract of nettle stem endophytic fungus on Escherichia coli has not an inhibition zone.

Antimicrobial Activity of Secondary Metabolites Isolated from Endophytic Fungi Associated with Rubiaceae Species

The effectiveness of antibiotics has declined significantly due to development of drug resistance. Consequently, it results in millions of deaths due to infectious diseases. Many studies have suggested that bioactive compounds produced by endophytes could be an alternative to discover new antimicrobial compounds. Endophytes are microorganisms that reside within the tissues of living plants that cause no apparent harm to the host. Fungal endophytes may biosynthesize the same or similar compounds as their host plant and other diverse bioactive compounds, which provide various pharmacological activities. Therefore, this study aimed to conduct literature search on the antimicrobial properties of the isolated compounds produced by fungal endophytes associated with Rubiaceae. Literature was conducted on secondary metabolites of endophytic fungi via four databases; EBSCOhost, Google Scholar, PubMed, and Scopus. A search filter was performed to include only research articles from 2007 to 2021. The search was restricted to publications in English only. Overall, 29 publications were selected for full-text evaluation and were included in the study. Results showed that sixteen antimicrobial metabolites were isolated from six fungal endophytes of ten different plant species were identified. These compounds were classified as alkaloid, phenol, coumarin, steroid, diterpene, and meroterpene.

Evaluation of the antimicrobial and cytotoxic potential of endophytic fungi extracts from mangrove plants Rhizophora stylosa and R. mucronata

Mangrove endophytic fungi are tolerant to numerous stresses and are inevitably capable of exhibiting excellent biological activity by producing impressive numbers of metabolites with special biological functions, based on previous work on the biological potential of mangrove-derived endophytic fungi. To obtain marked antimicrobial and cytotoxic fermentation products of culturable endophytic fungi from mangrove forests, our research evaluated the antimicrobial and cytotoxic activities of crude extracts of endophytic fungi from Rhizophora stylosa and Rhizophora mucronata. Forty-six fungal isolates were cultured on four different media, 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 the gram-negative bacteria Pseudomonas adaceae (PA), gram-positive bacteria Enterococcus faecalis (EF), methicillin-resistant Staphylococcus aureus (MRSA) and pathogenic fungus Monilia albicans (MA). The cytotoxic activity of the extracts was evaluated by MTT assay using A549 human lung cancer cells, HeLa human cervical carcinoma cells, and HepG2 human hepatocellular cells. The results showed that rice medium could promote the secretion of antimicrobial and antitumour secondary metabolites of endophytic fungi in comparison with other cultivation media. Seventeen strains (68%) from R. stylosa exhibited inhibitory effects on indicators, especially N. protearum HHL46, which could inhibit the growth of four microbes with MIC values reaching 0.0625 mg/mL. Fifteen strains (71.4%) from R. mucronata displayed activities against human pathogenic microbes; in particular, Pestalotiopsis sp. HQD6 and N. protearum HQD5 could resist the growth of four microbes with MIC values ranging from 0.015 to 1 mg/mL. In the cytotoxicity assay, the extracts of 10 strains (40%), 9 strains (40%) and 13 strains (52%) of R. stylosa and 13 strains (61.9%), 10 strains (47.6%) and 10 strains (47.6%) of R. mucronata displayed cytotoxicity against A549, HeLa and HepG2 cancer cells with cell viability values ≤ 50%. Neopestalotiopsis protearum HHL46, Phomopsis longicolla HHL50, Botryosphaeria fusispora HQD83, Fusarium verticillioides HQD48 and Pestalotiopsis sp. HQD6 displayed significant antitumour activity with IC50 values below 20 μg/mL. These results highlighted the antimicrobial and antitumour potential of endophytic fungi from R. stylosa and R. mucronata and the possibility of exploiting their antimicrobial and cytotoxic agents.

Antibacterial activity of endophytic fungi isolated from the stem bark of jambu mawar (Syzygium jambos)

Abstract. ‘Aini K, Elfita, Widyajanti H, Setiawan A, Kurniawati AR. 2021. Antibacterial activity of endophytic fungi isolated from the stem bark of jambu mawar (Syzygium jambos). Biodiversitas 23: 521-532. Syzygium jambos (jambu mawar) is widely used in South Sumatra as a traditional medicine to treat various diseases, including pathogenic bacterial infections. Literature studies report that parts of S. jambos have been used worldwide for treating diarrhea accompanied by fever, dysentery, sore throat, diabetes, and other infectious diseases. Endophytic fungi isolated from medicinal plants have high diversity, and the biological activity of their secondary metabolites is associated with their host. Therefore, this study aimed to determine the diversity of endophytic fungi from the stem bark of S. jambos and the antibacterial activity of secondary metabolites of endophytic fungi. Fungal isolates with high antibacterial activity were identified to obtain fungal species, and the structure of their compounds was determined. The disc diffusion method carried the antibacterial activity test against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli and Salmonella typhi) bacteria. Characteristics of endophytic fungi were identified microscopically and macroscopically. Active endophytic fungi were identified by molecular analysis of the internal transcribed region (ITS) of the ribosomal DNA. Isolation of antibacterial compounds using chromatographic techniques and determination of chemical structures using spectroscopy was performed. Eight endophytic fungi were obtained from the stem bark of S. jambos, namely SJ1–SJ8. The endophytic fungus SJ6 showed the highest activity and base on phylogenetic analysis, was identified as Fusarium verticillioides. Pure compounds isolated as yellowish-white solids showed good antibacterial activity against S. aureus and S. typhi with minimum inhibitory concentration values of 64 g/mL each. Based on 1D and 2D nuclear magnetic resonance spectroscopic analysis, compound 1 was identified as 3-hydroxy-4-(hydroxy(4-hydroxyphenyl)methyl)dihydrofuran-2-on.

Natural imidazole alkaloids as antibacterial agents against Pseudomonas syringae pv. actinidiae isolated from kiwi endophytic fungus Fusarium tricinctum

Kiwi (Actinidia chinensis) plants are severely destroyed by canker disease which is caused by the bacterium Pseudomonas syringae pv. actinidiae (Psa). This program tries to find anti-Psa agents among secondary metabolites of endophytic fungi from kiwi plant itself. The chemical investigation on one kiwi endophytic fungi, Fusarium tricinctum, resulted in the isolation of nine new imidazole alkaloids, fusaritricines A-I (1–9) together with seven known analogues (10–16). The structures of new compounds were established by extensive spectroscopic methods. Compounds 2, 3, 9, and 13 showed good antibacterial activity against Psa with MIC values between 25 and 50 μg/mL. It is suggested that imidazole alkaloids should be potential anti-Psa agents.

Susceptibility Studies of Vancomycin Resistant Staphylococcus aureus (VRSA), Extended ?-lactamase Producing Escherichia coli and P. falciparum to Ethylacetate Extract of Endophytic Fungal Metabolites from Annona senegalensis

Search for novel compounds can impact positively in the development of action plans in the control of existing and emerging antimicrobial drug-resistance (ADR). This study, aimed at assessing the susceptibility of vancomycin resistant Staphylococcus aureus (VRSA), extended ?- lactamase (ES?L) producing Escherichia coli and Plasmodium falciparum to ethyl acetate extract of secondary metabolites of endophytic fungi isolated from the leaves and root of Annona senegalensis Pers. Seven endophytic fungi were isolated from cultured, freshly collected root and leaves of A. senegalensis. Six (Root(RT)1, Root (RT)2, Root(RT)3, Leaf-Blade(LB)1, Mid-Rib(MR)1 and Mid-Rib(MR)2) out of the seven isolates whose toxicity profiles had been ascertained in our previous study were selected for antibacterial and antimalarial studies. The antibacterial activities of the endophytic fungal extracts were tested using the agar well diffusion technique. The activities were tested against VRSA and ES?L E. coli and ciprofloxacin- (5 µg) was used as the positive controls. In vitro anti-malarial activity was also carried out with the extracts. The result showed that out of the six isolates, RT1 metabolite had marked activities against ES?L E. coli and P. falciparum. Similarly, RT2, had an impressive activity against VRSA, ES?L E. coli and P. falciparum. The highest concentration of RT2 gave 58 % inhibition of the parasite whereas that of the control was 66 %. This impressive susceptibility of VRSA, ES?L E. coli and P. falciparum to these fungal metabolites call for further studies on these metabolites to purify and elucidate the bioactive component of each compound.

Secondary metabolites of endophytic fungi from Newbouldia laevis and Cassia tora leaves: prospecting for new antimicrobial agents.

This study tries to prospect for new antimicrobial agents using some Nigerian plants Background: Antimicrobial compounds from fungi endophytes have shown great promise in mitigating the threats of resistant pathogens. The study evaluated the in vitro antimicrobial property of secondary metabolites of endophytic fungi isolated from Newbouldia laevis and Cassia tora leaves. Ten endophytic fungi were isolated from the two plants' leaves and later fermented on local rice for 21 days. Thereafter, their secondary metabolites were extracted using ethyl acetate. The antibacterial activity of the extracts on the test organisms were determined using agar diffusion and agar dilution methods, while the bioactive constituents were identified using High performance liquid chromatography coupled to diode array detector. Nine of the crude extracts (NL1, NL3, NL6, NL10, NL12, CT2, CT7, CT9 and CT10) of the fungi isolates inhibited at least one of the microorganisms studied with maximum and minimum Inhibition-Zone-Diameter of 14 mm and 2 mm respectively while CT1 did not inhibit any of the tested microorganisms at tested concentrations. The extracts exhibited good antifungal activity, inhibiting the growth of both C. albicans and Trichophyton tested with an InhibitionZone-Diameter ranging between 4-8 mm and 7-14 mm respectively. The endophytic fungi extracts- CT2 and NL1- exhibited the best antimicrobial activity, inhibiting most of the tested microorganisms. HPLC-DAD analysis of the endophytic fungal extracts identified some classes of compounds such as catechin derivatives, benzoic acid derivatives and apigenin, which were previously reported to have antimicrobial potentials. Newbouldia laevis and Cassia tora leaves house endophytic fungi capable of yielding secondary metabolites with potential as anti-infective agents.

Challenges in the Use of Secondary Metabolites of Endophytic Fungi for the Control of Aedes Aegypti (Linnaeus, 1762)

Challenges in the Use of Secondary Metabolites of Endophytic Fungi for the Control of Aedes Aegypti (Linnaeus, 1762)

Anti-cervical cancer activity of secondary metabolites of endophytic fungi from Ginkgo biloba.

The purpose of this study was to isolate the secondary metabolites of endophytic fungi from Ginkgo biloba (SMEFGB) and investigate their anti-cervical cancer activity. SMEFGB were cultured. The secondary metabolites of endophytic fungi was extracted, purified and identified. The effects of secondary metabolites on proliferation, apoptosis and migration of human cervical cancer HeLa cells were determined. In addition, the effects of SMEFGB on growth of Hela implanted tumor in mice were investigated. In 9 stains of endophytic fungi successfully isolated from the leaves of Ginkgo biloba, the stain J-1, J-2 and J-3 could produce podophyllotoxin. These 3 stains were identified by molecular biology. The secondary metabolites of stain J-1, J-2 and J-3 markedly inhibited the proliferation of HeLa cells, promoted their apoptosis and blocked their migration. In addition, the secondary metabolites of stain J-1, J-2 and J-3 significantly attenuated the growth of HeLa implanted tumor in mice. Our results indicated that SMEFGB had obvious anti-cervical cancer activity in vitro and in vivo.

Characterization of Biomolecules with Antibiotic Activity from Endophytic Fungi Phomopsis Species

Recently, growing interest is devoted to investigation of bioactive secondary metabolites of endophytic fungi. Thus, as an extension to our previous achievements related to antimicrobial potential of endophytic fungi, Phomopsis species isolated from conifer needles was selected as appropriately promising natural source for drug discovery. Its dichloromethane and ethanol extracts considerably inhibited growth of Escherichia coli and Staphylococcus aureus. Moreover, the individual compounds of dichloromethane extract have been separated, collected and purified using semi preparative liquid chromatographic analysis and comprehensively characterized using mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). Based on their antimicrobial activity and unique structural characteristics in comparison with well-established drugs from the same therapeutic category, two dominant compounds (Z)-(Z)-2-acetoxyprop-1-en-1-yl-3-(3-((E)-3,4-dihydroxypent-1-en-1-yl)oxiran-2-yl)acrylate (denoted as 325-3) and (Z)-(Z)-2-acetoxyprop-1-en-1-yl 3-(3-((E)-4-hydroxy-3-oxopent-1-en-1-yl)oxiran-2-yl)acrylate (denoted as 325-5) were recognized as valuable leading structures for future discovery of novel antibiotics.

The anti-pseudomonal potentials of metabolites from some endophytic fungi isolated from Garcinia kola leaves

The morbidity and mortality rates from Pseudomonas aeruginosa infections are increasing, due to the development of drug-resistant strains. This study aimed to explore the secondary metabolites of endophytic fungi of Garcinia kola for their antibacterial activities against P. aeruginosa. The endophytic fungi associated with healthy leaves of G. kola were isolated using the standard methods. These fungi were subjected to solid-state fermentation on rice media at 28oC for 21 d. The fungal secondary metabolites were extracted using ethyl acetate, and then concentrated under vacuum. The fungal crude extracts were screened for their antibacterial activities against clinical and laboratory strains of P. aeruginosa, using the agar diffusion method. The bioactive components of the fungal extracts were identified using High-Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD) analysis. Three endophytic fungi mainly; Aspergillus sp., Fusarium sp. and Colletotrichum sp. were isolated. At concentration of 1 mg/ml, extracts of the three fungi displayed anti-pseudomonal activities against all the isolates, except for a P. aeruginosa isolate recovered from urine. Results of the HPLC-DAD analysis revealed the presence of several active compounds such as; indole-3-acetic acid, p-hydroxybenzoic acid, and protocatechuic acid, among others in the fungal extracts. These compounds have been previously reported to have significant antimicrobial properties. This study reveals that endophytic fungi associated with G. kola leaves possess promising anti-pseudomonal potential.

Isolation, identification and antimicrobial activity of secondary metabolites of endophytic fungi from annona leaves (Annona squamosa L.) growing in dry land

Research on isolation, identification, and antimicrobial activity of secondary metabolites of endophytic fungi from leaves of Annona squamosa growing in dryland had been undertaken. The work includes the isolation of endophytic fungi, cultivation, and extraction of fungal extract and identification of chemical metabolites together with the antibacterial test. The pure colony of endophytic fungi was grown on solid rice media using 1 L Erlenmeyer flask. The grown fungi were extracted with ethyl acetate. The ethyl acetate crude extract was then further subjected to chemical analysis and its antibacterial properties. Endophytic fungi species was identified as Aspergillus niger based on macroscopic and microscopic analysis. Analysis LC-MS/MS had revealed the presence of five metabolites including ephedradine A, ergosine, Ia, mudanpioside H, and trichosanic acid. The extract showed strong inhibition against Staphyloccus aureus with diameter of zone inhibition of 16.1 mm and moderate inhibition against Escherichia coli 0175H7 and Salmonella enteritidis ATCC 6939 with the observed diameter of zone inhibition of 9.6 mm and 11.3 mm, respectively.

Phylogenetic Analysis Of Endophytic Fungi Isolate from Bellucia pentamera Naudin Based On ITS rDNA

Endophytic fungi can produce secondary metabolites of endophytic fungi isolated from host plants. The purpose of this study is to identify and analyze the sequencing of endophytic fungi isolates with ITS and Beta-tubulin markers and phylogenetic trees. The endophytic fungi isolate DKJ1, DKJ3a, DKJ3c and DKJ4 were successfully isolated from the cardia plant (Bellucia pentamera Naudin) indicated by Aspergillus niger group, Aspergillus fumigatus group and Penicillium sp. The results of the sequencing analysis of isolates DKJ1, DKJ3a, DKJ3c, and DKJ4 were successfully amplified with an annealing temperature of 54ºC with a pair of ITS1-ITS4 primers with a molecular weight of 570 bp and a Beta-Tubulin primer with an annealing temperature of 56.1ºC molecular weight of 550 bp. From the results of identification and analysis of DNA sequencing of endophytic fungi DKJ1, DKJ3a, DKJ3c and DKJ4 with the primary pair of ITS and Beta-tubulin shows that the phylogenetic tree is different from the species obtained. ITS DKJ1 isolates have similarities with the species Aspergillus piperis CBS 112811, ITS DKJ3c has similarities with the species Aspergillus flavus var flavus strain ATCC 16833, ITS DKJ3a has similarities with Penicillium rolfsii strain NRRL 1078 species and ITS DKJ4 has similarities with Penicillium oxalicum NRRL 787 species. Whereas isolate from DKJ1 Beta-Tubulin has similarities with NRRL 4875 Aspergillus tubingensis species, DKJ3c has similarities with species of Aspergillus novoparasiticus strain DTO 223-C4 and DKJ4 has a similarity with Penicillium guaibinensis species. But there are similarities based on Cluster A (Aspergillus Group) and Cluster B (Penicillium Group) on phylogenetic trees.

Aktivitas Metabolit Sekunder Cendawan Endofit terhadap Colletotrichum acutatum pada Cabai Merah

Activity of Fungal Endophyte Secondary Metabolites against Colletotrichum acutatum on Chili PepperColletotrichum acutatum is one of anthracnose causal agents on chili pepper that has been reported to be predominant species in a some regions of Java Island. Secondary metabolites of endophytic fungi have been reported to have a potency as antifungal agents against plant pathogen. However, its antifungal activity against C. acutatum has not been reported yet. This study was aimed to evaluate the antifungal activity of fungal endophyte secondary metabolite against C. acutatum at in vitro and in vivo assay. In vitro assay was conducted to evaluate antifungal activity of fungal endophyte CBR1D14 isolate culture filtrate (FCBR) and mycelia extract (MCBR) in inhibiting conidial germination of C. acutatum. The results of in vitro assay showed that ethyl acetate extract of FCBR (EA FCBR) had the highest activity in inhibiting C. acutatum conidial germination. Methanol fraction from the partition of EA FCBR (FM FCBR) and from the partition of MCBR ethyl acetate extract (FM MCBR) showed the ability in inhibiting C. acutatum conidial germination. In vivo assay to chili pepper fruit showed that the treatment of FM FCBR (IC95 609.9 µg mL-1) and FM MCBR (IC95 1178.27 µg mL-1) decreased anthracnose disease incidence and lesion diameter. The efficacy rate of FM FCBR and FM MCBR treatments against anthracnose was 36.72 and 48.68%, respectively. Bioautography test was done on silica gel thin layer chromatogram. Methanol fraction of FCBR and MCBR were separated into 3 bioautographic spots respectively (Rf 0.04, 0.07, 0.7 for FM FCBR and Rf 0.06, 0.52, 0.7 for FM MCBR).

Polyketides from Marine-Derived Aspergillus porosus: Challenges and Opportunities for Determining Absolute Configuration

Fungal natural products have inspired and enabled countless modern therapeutics. During a survey of the secondary metabolites of endophytic fungi, we found that Aspergillus porosus produces new polyketides with interesting structural features named porosuphenols A-D (1, 2, 3a, and 3b). The structural elucidation of these metabolites was performed with 1D and 2D NMR techniques, Mosher ester analysis, J-based conformational analysis, and isotope exchange studies. The absolute configuration of these compounds was determined using typical approaches including comparative analysis of experimental NMR and electronic circular dichroism spectra with DFT calculations. However, these efforts did not provide conclusive results for porosuphenol A (1). To resolve this issue, we applied a strategy in which NMR data guide the conformer search. Herein are presented the structure elucidation of porosuphenols A-D as a case study in the challenges and opportunities for determination of absolute configuration. Lastly, bioassay-guided fractionation of cytotoxic fractions resulted in the additional isolation of pimarane diterpenes, sphaeropsidin A (4), and aspergiloid E (5).

Screening of metabolites from endophytic fungi of some Nigerian medicinal plants for antimicrobial activities

Abstract Endophytic fungi associated with Nigerian plants have recently generated significant interest in drug discovery programmes due to their immense potential to contribute to the discovery of new bioactive compounds. This study was carried out to investigate the secondary metabolites of endophytic fungi isolated from leaves of Newbouldia laevis, Ocimum gratissimum, and Carica papaya The plants were collected from Agulu, Anambra State, South-East Nigeria. Endophytic fungal isolation, fungal fermentation; and extraction of secondary metabolites were carried out using standard methods. The crude extracts were screened for antimicrobial activities using the agar well diffusion method, and were also subjected to high performance liquid chromatography (HPLC) analysis to identify their constituents. A total of five endophytic fungi was isolated, two from N. laevis (NL-L1 and NL-L2), one from O. gratissimum (SL-L1), and two from C. papaya (PPL-LAC and PPL-LE2). In the antimicrobial assay, the extracts of NL-L2, SL-L1, and PPL-LE2 displayed mild antibacterial activity against both Gram negative and Gram positive test bacteria. PPL-LAC extract showed mild activity only against S. aureus, while no antimicrobial activity was recorded for NL-L1 extract. All the endophytic fungal extracts showed no activity against the test fungi C. albicans and A. fumigatus HPLC analysis of the fungal extracts revealed the presence of ethyl 4-hydroxyphenyl acetate and ferulic acid in NL-L1; ruspolinone in NL-L2; protocatechuic acid, scytalone, and cladosporin in SL-L1; indole-3-acetic acid and indole-3-carbaldehyde in PPL-LE2; and indole-3-acetic acid in PPL-LAC. The findings of this study revealed the potentials possessed by these plants as source of endophytes that express biological active compounds. These endophytes hold key of possibilities to the discovery of novel molecules for pharmaceutical, agricultural and industrial applications.

In vitro assessment of antimicrobial and anti-inflammatory potential of endophytic fungal metabolites extracts

Endophytes are endosymbiotic microorganisms that act as reservoir of novel bioactive secondary metabolites with antimicrobial, cytotoxic and anti-cancer activities. In the present study, the extracts of 26 different endophytic fungal strains were screened for their antimicrobial and anti-inflammatory activities. The results showed a wide variety of antimicrobial activities against 12 target microorganisms including three Gram (+) bacteria, three Gram (-) bacteria, 3 yeasts, 2 dermatophytic fungi and one keratinophilic fungus. Four fungal extracts ( Aspergillus versicolor , A. awamori , A. niger and Penicillium funiculosum ) displayed a broader antibacterial spectrum and inhibited the growth of all Gram (+) and Gram (-) bacterial species. The extracts of 8 endophytic fungi inhibited the growth of the two tested dermatophytic strains ( Trichophyton mentagrophytes and T. rubrum ). Only eight fungal extracts have an inhibition activity against the keratinophilic fungal strain ( Chrysosporium tropicum ). The anti-inflammatory assay showed that the extracts of Emericella nidulans , Pleospora tarda and Penicillium funiculosum had good activities in inhibition of protein denaturation reached to 83%, 82.5% and 81.4%, respectively. Also, Emericella nidulans and Pleospora tarda recorded the maximum inhibition effect on bovine serum albumin denaturation reached to 95% and 90.7%, respectively. On the other side, Emericella nidulans showed the maximum inhibition activity (69.5%) out of all tested endophytic strains against humun red blood cells membrane stabilization assay. In conclusion some secondary metabolites of endophytic fungi have a promising potential as antimicrobial and anti-inflammatory compounds.