Root-associated endophytic fungi modulate endogenous auxin and cytokinin levels to improve plant biomass and root morphology of trifoliate orange

Root-associated endophytic fungi like Serendipita indica and arbuscular mycorrhizal(AM) fungi can improve plant growth and root construction, but the potential mechanism is unclear. In this study, Funneliformis mosseae(an AM fungus) and S. indica, singly or in combination were inoculated into trifoliate orange(Poncirus trifoliata) seedlings, to assess changes in biomass and root morphological traits, coupled with auxins and cytokinins concentrations in leaves and roots and the expression of auxin synthesis and transporter protein genes. After 20 weeks of inoculation with these fungi, shoot and root biomass, root total length, taproot length, average diameter, surface area, volume, and the number of lateral roots in 1st-, 2nd-, and 3rd-order were improved, and S. indica showed a relatively greater effect than F. mosseae and dual inoculation. Endophytic fungal inoculation also significantly increased the concentration of indoleacetic acid, indole butyric acid, trans-zeatin,dihydrozeatin, and isopentenyl adenine in leaves and roots, whilst F. mosseae and S. indica exhibited relatively greater effects on leaves and roots, respectively. Correlation analysis revealed that both biomass and root morphological traits(except root projected area) were significantly positively associated with endogenous auxins and cytokinins. In addition, the inoculated plants recorded comparatively higher expression levels of indoleacetic acid synthesis genes(PtTAA1, PtTAR2, PtYUC3, PtYUC4, PtYUC6, and PtYUC8) and indoleacetic acid transporter protein genes(PtAUX1, PtLAX1, PtLAX2, PtLAX3, PtPIN1, PtPIN3, PtPIN4, PtABCB1, and PtABCB19) than the non-inoculated plants, among which F. mosseae and S. indica showed better effects in leaves and roots, respectively. These results suggest that root-associated endophytic fungi improved plant growth and root architecture, which were associated with changes in endogenous auxins and cytokinins.

Identification and Bioactivities of Secondary Metabolites Derived from Endophytic Fungi Isolated from Ethnomedicinal Plants of Tujia in Hubei Province:A Review

Tujia is a national minority,inhabiting in the mountainous Wuling area in China.Since 1978,Tujia medicine has been studied,summarized and developed,leading to numerous achievements by Chinese researchers,such as the publishing of approximately 30 monographs of Tujia medicine.These publications are focused on summarizing and improving the theory of Tujia medicine and developing clinical therapies from this system of medicine.The shortage of natural medicinal plants used in Tujia medicine has created the need to discover new resources to replace them and protect endangered natural plant species.Endophytic fungi are one of the conservation options,are considered a source of new bioactive natural products,and are a renewable and inexhaustible source of new drugs and agrochemicals.This review summarizes 260 compounds from endophytic fungi that have been previously isolated from the medicinal plants of Tujia.These compounds include steroids,terpenoids,meroterpenoids,polyketides,alkaloids,peptides,aliphatic compounds,aromatic compounds,and heterocyclic compounds.

A pilot study of antioxidant potential of endophytic fungi from some Sudanese medicinal plants

Objective: To evaluate the total phenolic content and total antioxidant capacity of ethyl acetate extracts of 21 endophytic fungi isolated from five Sudanese medicinal plants: Calotropis procera, Catharanthus roseus, Euphorbia prostrate, Vernonia amygdalina and Trigonella foenumgraecum. Methods: Crude extracts of endophytic fungi and their host plants were tested by classical Folin-Ciocalteu colorimetric method to determine the total phenolic content, also total antioxidant capacity was estimated using 1,1-diphenyl-2-picrylhydrazyl free radical scavenging in vitro method. Results: Among the endophytes, endophytic fungus Aspergillus sp. from Trigonella foenum-graecum seeds demonstrated the highest both total phenolic content in term of gallic acid equivalent(GAE) [(89.9±7.1 mg GAE/g)] and antioxidant activity for 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay [IC50:(18.0±0.1 μg/m L)]. A high positive linear correlation(R2=0.999 1) was found between total antioxidant capacity and total phenolic content of endophytic fungi isolated from Vernonia amygdalina. Conclusions: The present study revealed that some endophytic fungi from the five Sudanese medicinal plants could be a potential source of novel natural antioxidant compounds.

Levels of rhizome endophytic fungi fluctuate in Paris polyphylla var.yunnanensis as plants age

Paris polyphylla var. yunnanensis is an important medicinal plant with abundant saponins that are widely used in the pharmaceuticals industry. It is unclear why the levels of active ingredients increase as these plants age. We speculated that the concentrations of those components in the rhizomes are mediated by fungal endophytes. To test this hypothesis, we took both culture-dependent and-independent(metagenomics) approaches to analyze the communities of endophytic fungi that inhabit those rhizomes in plants of different age classes(four, six, and eight years old). In all, 147 isolates representing 18 fungal taxa were obtained from 270 segments(90 per age class). Based on morphological and genetic characteristics, Fusarium oxysporum(46.55% frequency of occurrence) was the predominant endophyte,followed by Leptodontidium sp.(8.66%) and Trichoderma viride(6.81%). Colonization of endophytic fungi was maximized in the eight-year-old rhizomes(33.33%) when compared with four-year-old(21.21%) and six-year-old(15.15%) rhizomes. Certain fungal species were present only at particular ages. For example,Alternaria sp., Cylindrocarpon sp., Chaetomium sp., Paraphaeosphaeria sporulosa, Pyrenochaeta sp., Penicillium swiecickii, T. viride, and Truncatella angustata were found only in the oldest plants. Analysis of(metagenomics) community DNA extracted from different-aged samples revealed that, at the class level,the majority of fungi had the highest sequence similarity to members of Sordariomycetes, followed by Eurotiomycetes and Saccharomycetes. These results were mostly in accord with those we obtained using culture methods. Fungal diversity and richness also changed over time. Our investigation is the first to show that the diversity of fungi in rhizomes of P. polyphylla var. yunnanensis is altered as plants age, and our findings provide a foundation for future examinations of useful compounds.

Purification of four strains of endophytic fungi from Astragalus and their optimized liquid fermentations

This study was designed to isolate endophytic fungi from A. mongholicus （growing in northeast China） to determine whether they can produce bioactive metabolites. Four strains of endophytic fungi （strains 16, 17, 23 and 75） were successfully isolated from A. mongholicus using the surface disinfection method. According to ITS-rDNA sequences analysis, strains 16 and 75 were identified as Fusarium oxysporum, and strains 17 and 23 were identified as Bionectria ochroleuca. We applied the Box-Behnken design （BBD） to optimize the liquid fermentation conditions and obtain the maximum cell dry weight （CDW） yield. Opti-mal parameters were obtained under the following experimental condi-tions：temperature of 28＆#176;C, potato dextrose agar （PDA） liquid medium of 80 mL and rotation speed of 150 rpm. The four isolated endophytic fungi did not produce astragalosides I-IV, flavonoids or polysaccharides. Iso-lation of additional species of endophytic fungi from A. mongholicus and determination of their capacity to produce biologically active substances are subjects in need of further research.

Three Novel Endophytic Fungi as Potential Candidates Producing Bioactive Metabolites Isolated from Metasequoia glyptostroboides

[Objectives]This study was conducted to isolate and investigate the endophytic fungi with antimicrobial activity from the healthy leaves and bark of Metasequoia glyptostroboides Hu&W.C.Cheng regarded as an important medicinal plant in China.[Methods]Endophytic fungi with visible antimicrobial activity were isolated from the healthy leaves and bark of M.glyptostroboides,and primarily screened using Escherichia coli and Staphylococcus aureus as test microorganisms.[Results]Three isolates with relatively higher antimicrobial activity,labeled as MG-01,MG-02,MG-09,were selected for study.Molecular and morphological analysis indicated that the three isolated endophytes belong to Penicillium sp.The ethyl acetate(EtOAc)extracts of the three endophytes were obtained and subjected to the disk diffusion assay,using E.coil,S.aureus,Pseudomonas aeruginosa,Enterococcus faecalis,Monilia albicanas,and Bacillus subtilis as test microorganisms.The minimum inhibitory activity(MIC)of the endophyte with relatively highest antimicrobial activity was determined using two-fold broth micro-dilution method.All the endophytes showed a broad spectrum antimicrobial activity.Among the three endophytes,the strain MG-09 exhibited relatively highest antimicrobial activity with the zones of inhibition(ZOI)ranging from 14.15 to 24.07 mm and MIC ranging from 416.67 to 65.11μg/ml.[Conclusions]The endophytic fungi colonized in M.glyptostroboides are capable of producing effective antimicrobial compounds which may be a potential source for drug discovery and biocide production.

Anticancer activity test of ethyl acetate extract of endophytic fungi isolated from soursop leaf(Annona muricata L.)

Objective: To analyze anticancer activity of an ethyl acetate extract of endophytic fungi isolated from soursop leaf(Annona muricata L.). Methods: Anticancer activity of fungal extracts was determined by observing its toxicity against MCF-7(Michigan Cancer Foundation-7) cells in vitro by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay method. At an extract concentration of 100 μg/m L, 4 isolates out of 12 showed high activity against the cancer cell growth. The four isolates were then selected for further IC50 determination, by measuring the inhibition of cancer cell proliferation at extract concentration of 25 μg/m L, 50 μg/m L, 100 μg/m L, 200 μg/m L and 400 μg/m L. Results: Results showed that isolate Sir-G5 had the highest anticancer activity with an IC50 of 19.20 μg/m L. The best isolates were screened again using a normal cell(Chang cells) to determine its toxicity against normal cells. Results indicated that the extracts do not affect the proliferation of normal cells. Molecular identification showed that the fungal isolate Sir-G5 has a close relationship with Phomopsis sp. Conclusions: The endophytic fungi isolated from soursop leaf has the potential to be used as a source of anticancer agents.

Community Structure of Endophytic Fungi in Ginseng and Its Correlation Analysis with Active Components

[Objectives]The paper was to explore the correlation between active components of ginseng and community structure of endophytic fungi in ginseng under different cultivation methods.[Methods]Using ginsengs under two main planting patterns in Huanren County,Liaoning Province as the samples,the community structure of endophytic fungi was studied by molecular means,and the chemical components were identified and the content of chemical markers was measured via LC-MS.Moreover,the correlation between medicinal components of ginseng and diversity of endophytic fungal flora was analyzed.[Results]The diversity and active components of endophytic fungi of ginseng were different.The diversity analysis showed that the medicinal components of ginseng were positively correlated with some fungal groups in ginseng.[Conclusions]Artificial intervention in the planting process would affect the endophytic fungi in medicinal materials,and further affect the chemical components of ginseng medicinal materials.

Endophytic Fungi Associated with a Holoparasitic Plant, Balanophora japonica (Balanophoraceae)

Holoparasitism is a special life cycle of flowering plants. All carbon resources are provided by photosynthetic host plants. A recent study revealed the presence of endophytic fungi in holoparasitic plants, but their ecological and evolutionary roles are still unknown. In this study, we examined endophytic fungi isolated from the holoparasitic plant Balanophora japonica (Balanophoraceae), collected from Kochi, Shikoku in western Japan. We isolated 23 fungal strains on inflorescences and tubers from three B. japonica plants at two locations and on one sample of the host plant (Symplocos lancifolia, Symplocaceae). Predominant isolates were Trichoderma-Hypocrea, Penicillium and Phialemonium. The first group was also predominant in the host plant. Fungal composition revealed in this study differed from the composition on B. harlandii or other root holoparasites with endophytic fungal (Rafflesia cantleyi) data. Those differences might be caused by various factors, including growth habits, location, phylogenetic position or host-parasite relationship.

Isolation, Identification and Pharmacological Activities of Endophytic Fungi from <i>Aponogeton undulatus</i>Roxb.

The objective of this study is to isolate, identify and investigate the pharmacological activities of the endophytic fungi from an aquatic plant Aponogeton undulatus Roxb. (A. undulatus). Endophytic fungi were isolated and identified based on morphological characters. The molecular identification of the fungal isolates was performed using by analyzing the DNA sequence based on mega BLAST program. Spectrums of antibacterial and antifungal activities were studied by Agar diffusion methods. Extracts of the endophytic fungal strains isolated from the plant A. undulatus were screened for probable cytotoxic activities using brine shrimp lethality bioassay. Six endophytic fungi, namely AULE-1, AULE-2, AULE-3, AURE-1, AURE-3 and AURE-4 were isolated and purified from the leaves and roots of the plant such as strains AULE-1 as Trichooderma sp., AULE-2 as Carvularia sp. AULE-3 as Penicillium sp. strains AURE-1 and AURE-4 as Fusarium sp. and AURE-3 as Mucor sp. Strain AURE-4 was further identified as Fusarium solani. At 300 μg/disc concentration, six ethyl acetate extracts of endophytic fungi of the plant A. undulates showed moderate to significant activities against most of the test bacteria and pathogenic fungi. The strain AURE-4 exhibited strong cytotoxic activities (10.18 μg/mL) compared to the standard antitumor agent vincristine sulphate and this positive result suggests that fungal extracts may contain antitumor or pesticidal compounds. This is the first study to report the isolation, identification, antimicrobial and cytotoxic properties of endophytic fungi of Aponogeton undulatus Roxb. in Bangladesh.

Diversity of endophytic fungi associated with the medicinally important aromatic plant Gaultheria fragrantissima

A total of thirty three(33)endophytic fungi including sterile mycelia were isolated from the leaf,stem and roots of medicinally important aromatic plant Gaultheria fragrantissima.Majority of the fungi belonged to the phylum Ascomycota.The total percentage colonization frequency(%CF)of each endophytic fungal species was calculated of which Juxtiphoma eupyrena showed highest colonization frequency(20.14%)in the leaf whereas Globisporangium irregulare was found to have highest colonization frequency in the stem(14.58%)and in the roots,Trichoderma viride was observed to have the highest colonization frequency of 21.43%.Diversity of endophytic fungi in the roots was found to be higher as compared to the other plant tissues.

Potential use of cucumber (Cucumis sativus L.) endophytic fungi as seed treatment agents against root-knot nematode Meloidogyne incognita

Seed treatment with endophytic fungi has been regarded as an effective method for plant parasitic nematode control.Endophytic fungi from cucumber seedlings were isolated and screened for their potential to be used as seed treatment agents against Meloidogyne incognita.Among the 294 isolates screened,23 significantly reduced galls formed by M.incognita in greenhouse test.The 10 most effective isolates were Fusarium(5),Trichoderma(1),Chaetomium(1),Acremonium(1),Paecilomyces(1),and Phyllosticta(1) .Their control efficacies were repeatedly tested and their colonizations as well as in vitro activity against M.incognita were studied.They reduced the number of galls by 24.0%-58.4%in the first screening and 15.6%-44.3%in the repeated test,respectively.Phyllosticta Ph511 and Chaetomium Ch1001 had high colonizations on both the roots and the aboveground parts of cucumber seedlings.Fusarium isolates had colonization preference on the roots,their root colonizations ranging from 20.1%to 47.3%of the total root area.Trichoderma Tr882,Paecilomyces Pa972,and Acremonium Ac985 had low colonizations on both the roots and the aboveground parts.Acremonium Ac985,Chaetomium Ch1001,Paecilomyces Pa972,and Phyllosticta Ph511 produced compounds affecting motility of the second stage juveniles of M.incognita.Based on these results,Chae-tomium Ch1001 was considered to have the highest potential as a seed treatment agent for M.incognita biocontrol.

Antitumor and antimicrobial activities of endophytic fungi from medicinal parts of Aquilaria sinensis

The purpose of this study was to isolate and characterize endophytic fungi from the stem tissue which can produce fragrant ingredients in Aquilaria sinensis(also called agarwood) to determine their antitumor and antimicrobial activities.Twenty-eight fungal endophytes were isolated from agarwood by strict sterile sample preparation and were classified into 14 genera and 4 taxonomic classes(Sordariomycetes,Dothideomycetes,Saccharomycetes,and Zy-gomycetes) based on molecular identification.Of the 28 isolates,13(46.4%) showed antimicrobial activity against at least one of the test strains by the agar well diffusion method,and 23 isolates(82.1%) displayed antitumor activity against at least one of five cancer cell lines by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay.The diameters of inhibition zones of YNAS07,YNAS14,HNAS04,HNAS05,HNAS08,and HNAS11 were equal to or higher than 14.0 mm against Staphylococcus aureus,Escherichia coli,Bacillus subtilis,B.subtilis,Aspergillus fumigatus,and B.subtilis,respectively.The inhibition rates of YNAS06,YNAS08,and HNAS06 were not less than 60% to 293-T,293-T,and SKVO3 cells,respectively.These results suggest that the endophytic fungi associated with agarwood will provide us with not only useful micro-ecological information,but also potential antimicrobial and anti-tumor agents.

Endophytic fungi harbored in Cannabis sativa L.:diversity and potential as biocontrol agents against host plant-specific phytopathogens

The objective of the present work was isolation,phylogenetic characterization,and assessment of biocontrol potential of endophytic fungi harbored in various tissues(leaves,twigs,and apical and lateral buds)of the medicinal plant,Cannabis sativa L.A total of 30 different fungal endophytes were isolated from all the plant tissues which were authenticated by molecular identification based on rDNA ITS sequence analysis(ITS1,5.8S and ITS2 regions).The Menhinick’s index revealed that the buds were immensely rich in fungal species,and Camargo’s index showed the highest tissue-specific fungal dominance for the twigs.The most dominant species was Penicillium copticola that could be isolated from the twigs,leaves,and apical and lateral buds.A detailed calculation of Fisher’s log series index,Shannon diversity index,Simpson’s index,Simpson’s diversity index,and Margalef’s richness revealed moderate overall biodiversity of C.sativa endophytes distributed among its tissues.The fungal endophytes were challenged by two host phytopathogens,Botrytis cinerea and Trichothecium roseum,devising a dual culture antagonistic assay on five different media.We observed 11 distinct types of pathogen inhibition encompassing a variable degree of antagonism(%)on changing the media.This revealed the potential chemodiversity of the isolated fungal endophytes not only as promising resources of biocontrol agents against the known and emerging phytopathogens of Cannabis plants,but also as sustainable resources of biologically active and defensive secondary metabolites.

Factors shaping community structure of endophytic fungi–evidence from the Pinus-Viscum-system

Endophytic fungal communities have been shown to be highly diverse in almost every host plant species analyzed so far.However,the factors shaping their compositions are largely unknown.To elucidate the impact of various factors,10 independent replicates of DNA extracts from each of 17 surface-sterilized leaf and stem samples were analyzed by pyrosequencing of fungal ITS1 rRNA gene amplicons.Altogether,154 fungal OTUs(operational taxonomic units),represented by 953,385 sequences,were found in at least 2 samples from Viscum album ssp.austriacum and/or its host Pinus sylvestris.Deviating from earlier,cultivation-based assessments,the communities were dominated by OTUs related to the genus Mortierella and OTUs not assignable to a certain fungal phylum.However,Ascomycota were still the most diverse group in terms of OTU richness and already hypothesized organ and host preferences of certain endophytic Xylariaceae isolated from the Pinus-Viscum-system could be confirmed.Host species and organ type were also the major factors shaping the detected fungal communities.The two plant species clearly differed according to the endophytic fungal communities,but only stems and needles of Pinus were inhabited by significantly different fungal assemblages.Interestingly,only the 1 and 3 year old stem sections differed according to the endophytic fungal community,while differently aged leaves of both plants were indistinguishable in this regard.Size of the organs had no impact on fungal communities in Pinus,but shorter internodes and smaller leaves showed at least a tendency to differ from the corresponding larger organs in Viscum.Fungal communities also differed slightly between the two sampling sites,lying 200 km apart,and between the three sampling campaigns.Because the samples were drawn within 15 days,this finding indicates that seasonal shifts clearly outweigh aging effects in host plant with perennial leaves.The results therefore provide strong evidence against a linear development of the endophytic fungal communities in Pinus sylvestris and Viscum album over the years.The communities seem to establish themselves already in the year the respective organs emerge.Further study is required to clarify whether they predominantly establish anew each year,or if the core community persists throughout subsequent years.The most abundant endophytic OTUs are known from soil and/or dead plant material and are supposed to represent latent decomposers.The study reveals for the first time that host and/or organ preferences of putatively saprotrophic fungi are predominantly responsible for compositional differences in the endophytic fungal communities between host plants and organs.While the analyses are shown to provide rather robust results,the significance of genetic abundance,as revealed by high-throughput sequencing analyses,remains an unsettled issue.This is discussed in detail,as well as the challenges in assigning taxonomic names to OTUs.

Distribution and diversity of endophytic fungi in Gentiana rigescens and cytotoxic activities

Objective:In the present study,Gentiana rigescens was screened for fungi communities to clarify their diversity and community assemblage in hosts.Meanwhile,the identification and activity assays of the strains were also conducted.Methods:By culture-dependent(endophytic fungi isolations from plant sections)and culture-independent(metagenomic library and cloning from plant sections)techniques,fungi communities were studied.The metagenomic library was generated using direct DNA isolation of whole plants,plant radixes,plant stems,plant leaves,plant flowers and soils around the plant.Meanwhile,endophytes were isolated from all parts ofG.rigescens plants.After fermentation of the fungi isolations,all the isolates were evaluated for their cytotoxicity against four kinds of human cancer cell lines(HCT116,BEL7404,A549,MDA-MB-231).Results:Eventually,200 strains were isolated and 103 strains were further identified through the internal transcribed spacer(ITS,ITS1 and ITS2 regions)sequence by using the universal primers ITS5 and ITS4.A total of 59,106 fungal sequences corresponding to 374 putative operational taxonomic units(OTU)were identified by 454 pyrosequencing.Through 454 pyrosequencing,the main fungal genera were Sebacina,Botrytis,Mycosphaerella,Boletus and Gibberella,and the major fungal genera which were directly isolated were Aspergillus,Fusarium,Penicillium and Alternaria.Activity assays showed strains 5-26(Aspergillus sp.)and 6-2(Fusarium avenaceum)had the outstanding cytotoxicity to all the tested cell lines with IC5o values<5μg/mL.Conclusion:This study revealed the abundance of endogenetic fungal resources and a variety of genetic information in G.rigescens by high-throughput 454 sequencing technology and fungi isolation methods.Activity assays indicated that endophytes were a promising natural source of potential anticancer agents.

Antioxidant compounds produced by Pseudocercospora sp.ESL 02,an endophytic fungus isolated from Elaeocarpus sylvestris

Objective: To isolate endophytic fungi from Elaeocarpus sylvestris(E. sylvestris) and to isolate antioxidant compounds from a potential source fungus.Methods: Endophytic fungi were isolated from fresh leaves and stems of E. sylvestris and identified based on DNA analysis. 1,1-Diphenyl-2-picrylhydrazyl(DPPH) radical scavenging activity was used to evaluate the antioxidant activity of the fungi. The potential antioxidant fungus was further studied to isolate antioxidant compounds. The isolated compounds were identified by melting point analysis, optical rotation, spectral analysis using a UV spectrophotometer, high resolution fast atom bombardment mass spectrometry, X-ray crystallography analysis,~1H nuclear magnetic resonance analysis and ^(13)C nuclear magnetic resonance analysis. The isolated compounds were evaluated with DPPH radical scavenging, reducing power, and b-carotene bleaching assays.Results: Seven endophytic fungi were successfully isolated from E. sylvestris and identified as Pestalotiopsis sp. EST 01, Pestalotiopsis sp. EST 02, Diaporthales sp. EST03, Meyerozyma sp. EST 04, Diaporthales sp. EST 05, Pestalotiopsis sp. ESL 01, and Pseudocercospora sp. ESL 02. Of the seven fungi, Pseudocercospora sp. ESL 02 had the highest antioxidant activity [IC50=(30.54 ± 0.88) mg/mL]. From that fungus, two compounds identified as terreic acid(1) and 6-methylsalicylic acid(2) were isolated with an IC50 of DPPH radical scavenging activity of(0.22 ± 0.02) mmol/L and(3.87 ± 0.27)mmol/L, respectively. The compounds also had good activities from the reducing power and b-carotene bleaching assays.Conclusions: The Pseudocercospora sp. ESL 02 fungus isolated from E. sylvestris looks promising as a novel source of terreic acid.

Drimane Sesquiterpenoids and Isochromone Derivative from the Endophytic Fungus Pestalotiopsis sp. M-23

Three new drimane sesquiterpenoids(1–3)together with the known 2a-hydroxyisodrimeninol(4),and a new isochromone derivative(5),were obtained from the solid cultures of fungal strain Pestalotiopsis sp.M-23,an endophytic fungus isolated from the leaves of Leucosceptrum canum(Labiatae).Their structures were determined by comprehensive 1D and 2D NMR,and MS analyses.The metabolites were evaluated for their antibacterial activities,and compound 3 showed weak inhibitory activity against Bacillus subtilis.

α-Glucosidase inhibitor produced by an endophytic fungus, Xylariaceae sp. QGS 01 from Quercus gilva Blume

Xylariaceae sp.QGS 01,an endophytic fungus isolated from the stem of Quercus gilva Blume showed high-glucosidase inhibitory activity.α-Glucosidase inhibitor have the role as one of carbohydrate-hydrolyzing enzymes to postpone absorption of glucose in the digestive organs.The α-glucosidase inhibitor constituents were isolated from the ethyl acetate extract of the mycellium of endophytic fungi Xylariaceae sp.QGS 01 using a bioassay-guided fractionation technique.Further separation and purification of the active fraction led to the isolation of constituents with strong inhibitory activities against-glucosidase:8-hydroxy-6,7-dimethoxy-3-methylisocoumarine(1)with inhibitory concentration(IC50)values against-glucosidase from Saccharomyces cerevisiae of 41.75μg/mL,while quercetin as the standard had an IC50 value of 4.80g/mL.The results of the present study showed that the endophytic fungus Xylariaceae sp.QGS 01 is potentially a rich source of antidiabetic medicine.

Evaluation of the Antimicrobial Activity of Endophytic Fungus Isolated from <i>Cocos nucifera</i>(L.) Cotyledon against Medically-Important Pathogens

The study aimed to evaluate the endophytic fungi isolated from Cocos nucifera (L.) cotyledon for their possible antimicrobial activity. A total of twelve endophytic fungal species were successfully isolated, from which five were selected and presumptively identified, including Aspergillus niger, Raffaelea sp., Aspergillus flavus, Cladosporium sp. and Pseudallescheria spp. based on their macro and microscopic characters. The agar blocks of actively growing pure culture were assessed for antibacterial activity against five human pathogenic bacterial and fungal strains: Escherichia coli (BIOTECH 1634), Bacillus subtilis (BIOTECH 1697), Staphylococcus aureus (BIOTECH 1592), Serratia marcescens (BIOTECH 1748), and Candida tropicalis (BIOTECH 2085). Among the selected five endophytic used for antimicrobial activity screening, the Raffaelea sp. (CN-EF 2) has shown a high zone of inhibition of 11 mm against Bacillus subtilis, 18 mm against Escherichia coli, 15 mm against Staphylococcus aureus, and 11 mm against Candida tropicalis. Correspondingly, Aspergillus niger (CN-EF 1) has shown a zone of inhibition of 16 mm against C. tropicalis. The endophytic fungus Raffaelea sp. was effective against all test organisms except for Serratia marcescens, while Aspergillus niger was only effective for pathogenic fungi C. albicans. Hence, further in-depth studies of the isolated endophytic fungi are needed to determine the mechanisms behind the endophytes’ inhibitory effects.