Mining and identification of a biosynthetic gene cluster producing xanthocillin analogues from Penicillium chrysogenum MT-40, an endophytic fungus of Huperzia serrata / 生物工程学报

Xanthocillin is a unique natural product with an isonitrile group and shows remarkable antibacterial activity. In this study, the genome of an endophytic fungus Penicillium chrysogenum MT-40 isolated from Huperzia serrata was sequenced, and the gene clusters with the potential to synthesize xanthocillin analogues were mined by local BLAST and various bioinformatics analysis tools. As a result, a biosynthetic gene cluster (named for) responsible for the biosynthesis of xanthocillin analogues was identified by further heterologous expression of the key genes in Aspergillus oryzae NSAR1. Specifically, the ForB catalyzes the synthesis of 2-formamido-3-(4-hydroxyphenyl) acrylic acid, and the ForG catalyzes the dimerization of 2-formamido-3-(4-hydroxyphenyl) acrylic acid to produce the xanthocillin analogue N, N'-(1, 4-bis (4-hydroxyphenyl) buta-1, 3-diene-2, 3-diyl) diformamide. The results reported here provide a reference for further discovery of xanthocillin analogues from fungi.

Study on alkaloids of endophytic Trichoderma atroviride B7 from Colquhounia coccinea var. mollis / 药学学报

Nine compounds were isolated from the crude extract of the solid culture of endophyte Trichoderma atroviride B7 of Colquhounia coccinea var. mollis by silica gel column chromatography, Sephadex LH-20 gel column chromatography, and HPLC. They were identified as atroviridanol (1), 3-oxo-3-[(2-phenylethyl) amino]-propanoic acid (2), N-(2′-phenylethyl)-acetamide (3), neoechinulin A (4), echinulin (5), gancidin W (6), N-isobutyl-3-methylbutanamide (7), 5-acetamido-1-pentanol (8), and N-2-methylpropyl-2-methylbutenamide (9) by NMR, HR-MS, and so on. Among them, compound 1 is a new compound, and compounds 2-9 are firstly isolated from Trichoderma spp.

Secondary metabolites of endophytic fungus Aspergillus sp. J218 from Anectochilus roxburhii / 药学实践杂志

Objective To isolate the secondary metabolites of endophytic fungus Aspergillus sp. J218 from Anectochilus roxburhii. Methods Different chromatographic methods, including Sephadex LH-20 and silica gel chromatography as well as HPLC, were used to isolate compounds from the EtOAc fraction of the solid fermentation of J218, and their structures were identified by spectral methods. Results Ten compounds were isolated from the fermentation of J218 and their structures were individually identified as kotanin（1）, flavasperone（2）, aurasperone B（3）, fonsecinone B（4）, fonsecinone D（5）, ensidol A（6）, fonsecinone A（7）, fonsecinone C（8）, aurasperone A（9）, and fonsecinone F（10）. Conclusion Most compounds isolated from endophytic fungus Aspergillus sp. J218 in Anectochilus roxburhii were identified as dimeric naphthopyrones. These results suggest that this strain contains rich dimerization synthase, which could provide clues for the further exploration of the rational biosynthesis pathway of dimeric naphthopyrones in this strain.

Isolation and morphological identification of endophytic fungi from leaves and stems of Aquilaria malaccensis Lamk. originating from Java Island, Indonesia

Aims@#Endophytic fungi are the remarkable category of host-associated fungal community that invades the intercellular regions of host tissues, benefiting their host while obtaining an advantage. Fungal endophytes have lately attracted prominence as a source of active secondary metabolites. This investigation aimed to identify fungal endophytes that reside inside the leaves and stems of Aquilaria malaccensis.@*Methodology and results@#Healthy A. malaccensis stems and leaves samples were collected. Clean leaves and stems were cut to a size of 1 cm, followed by sterilization using 75% ethanol for 1 min, 3% sodium hypochlorite solution for 1 min, and finally, rinsing with sterile water 3 times for 1 min and drying with sterile paper. The sterile samples were put onto Potato Dextrose Agar (PDA) media containing chloramphenicol for 7-14 days until the mycelium grew for morphological identification under a light microscope. Five endophytic fungi were recovered from leaves, while nine endophytic fungi were obtained from stems. Using morphological approaches, nine of the endophytes had observed to produce conidia fungi, whereas the others did not. Neopestalotiopsis sp., Aspergillus sp., Arthrinium sp., Curvularia sp., Podospora sp., Mucor sp. and Verticillium sp. were identified as nine of the fourteen endophytes.@*Conclusion, significance and impact of study@#The number of endophytic fungi discovered in different organs varies. Not all endophytic fungi that grow can create sexual phages. Six genera of endophytic fungi were identified.

Filtrates from cultures of endophytic fungi isolated from leaves of Copaifera oblongifolia (Fabaceae) affect germination and seedling development differently / Fungos endofíticos isolados de folhas de Copaifera oblongifolia (Fabaceae) afetam diferentemente a germinação e o desenvolvimento das plântulas

Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.

As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.

Filtrates from cultures of endophytic fungi isolated from leaves of Copaifera oblongifolia (Fabaceae) affect germination and seedling development differently

Abstract Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.

Resumo As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.

Filtrates from cultures of endophytic fungi isolated from leaves of Copaifera oblongifolia (Fabaceae) affect germination and seedling development differently / Fungos endofíticos isolados de folhas de Copaifera oblongifolia (Fabaceae) afetam diferentemente a germinação e o desenvolvimento das plântulas

Abstract Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.

Resumo As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.

Screening and molecular identification of endophytic fungi promoting accumulation of flavonoids in callus of Scutellaria baicalensis / 中国中药杂志

To screen and identify the endophytic fungal strains that could promote the accumulation of flavonoids in the callus of Scutellaria baicalensis. Seventeen endophytic fungal strains from S. baicalensis were used to prepare mycelium elicitors and fermentation broth elicitors. Their effects on flavonoid accumulation in S. baicalensis callus were then determined. The results showed that the fermentation broth elicitors of two strains(CL79, CL105) promoted the accumulation of flavonoids. The fermentation broth elicitor of CL79 significantly promoted accumulation of baicalin, wogonoside, baicalein, and wogonin, with the maximum levels increased by 37.8%, 40.4%, 44.7%, and 42.2%(vs. blank), respectively. Similarly, the fermentation broth elicitor of CL105 significantly promoted the accumulation of baicalin, wogonoside, baicalein, and wogonin, with the maximum levels increased by 78.1%, 140.9%, 275.6%, and 208.5%(vs. blank), respectively. CL79 was identified as Alternaria alternata, and CL105 as Fusarium solani. The fermentation broth elicitors of A. alternata CL79 and F. solani CL105 were able to promote the flavonoid accumulation in the callus of S. baicalensis, which enriched the resources of endophytic fungi and provided candidate strains for the development of microbial fertili-zers for improving the quality of S. baicalensis.

Secondary metabolites of the endophytic fungus Aspergillus sp.Dq-25 from barnacle / 中国药科大学学报

@#The chemical constituents of solid rice culture of the endophytic fungus Aspergillus sp.Dq-25 from barnacle were isolated and purified by silica gel, Sephadex LH-20, C18 reversed silica gel column chromatography and recrystallization.Their structures were identified by the physical and chemical properties, and by various spectroscopic methods.Six compounds were isolated and identified as: demethyldihydropenicillic acid (1), dihydropenicillic acid (2), penicillic acid (3), fortisterol (4), 22E, 24R-3P, 5a-dihydroxyerogosta-7, 22-diene-6-one (5), and (22E, 24R)-ergosterol-7, 22-diene-3β, 5α, 9α-triol-6-one (6).Compound 1 was a new butyrolactone.MTT method was used to analyze cytotoxicity, and the result showed that compound 3 exhibited inhibitory activity on five cell lines, including K562, HeLa, SGC-7901, A542 and BEL-7402, with IC50 values of 38.0 ~ 105.0 μmol/L.

Isolation, Identification and Evaluation of the Plant Growth Promoting Activities of Endophytic Stenotrophomonas maltophilia to Stimulate Growth of Clover Plants under Salt Stress

Two endophytic bacterial isolates were obtained from root nodules of clover plants grown in salt affected clay soil of Egypt. The isolates were closely linked to Stenotrophomonas maltophilia strains IPR-Pv696 and 262XG2 based on the sequencing and phylogenetic analysis of 16S rRNA genes, and deposited in GenBank with accession numbers OM980221.1 (AM1) and OM980223.1 (AM2) respectively. The isolates were evaluated for their potential to promote plant growth. The results revealed that the two isolates of S. maltophilia strains (IPR-Pv696 and 262XG2) respectively exhibited production for indole-3- acetic acid (30.26 & 31.15 µg/ml), exopolysaccharides (13.57 & 13.68 g/l), nitrogen fixation activity and they solubilize the phosphate (278 & 208 mg/l) and potassium (33.5 & 32.9 µg/ml). In a field trial, these two isolates increased clover plant growth, chlorophyll, carbohydrates content and nutrients uptake while lowering proline levels. Hence this highlights its application to be exploited as biofertilizer by leading to sustainable agriculture. This could be a promising inoculant for many other crops.

Endophytic bacteria promote growth and increase the aloin content of Aloe vera / Las bacterias endofíticas promueven el crecimiento y aumentan el contenido de aloína del Aloe vera

Aloe vera is among the world's economically most important medicinal plants, but as the growth of this plant and, consequently, the accumulation of metabolites is slow, we tested the hypothesis that root endophytic bacteria isolated from A. vera plants can promote growth and increase the accumulation of aloin in the gel and latex. For this, we inoculate seedlings with four endophytic bacteria and a combination of them. We confirmed the hypothesis and identified two strains with potential for the formulation of inoculants to improve the cultivation of A. vera. The bacterium 149H Paraburkholderiasp. increases the number of leaves and the accumulation of biomass, but on the other hand, 35V Enterobacter ludwigii inoculation increased the content of aloin in the gel and in the latex. Further research should focus on the association of these two strains in a single inoculant, to both promote growth and increase the synthesis of metabolites.

Aloe vera se encuentra entre las plantas medicinales económicamente más importantes del mundo, pero como el crecimiento de esta planta y, en consecuencia, la acumulación de metabolitos es lento, probamos la hipótesis de que las bacterias endofíticas de raíces aisladas de las plantas de A. vera pueden promover el crecimiento y aumentar la acumulación de aloína en el gel y látex. Para ello, inoculamos plántulas con cuatro bacterias endofíticas y una combinación de ellas. Confirmamos la hipótesis e identificamos dos cepas con potencial para la formulación de inoculantes para mejorar el cultivo de A. vera. La bacteria 149H Paraburkholderia sp. aumenta el número de hojas y la acumulación de biomasa, pero, por otro lado, la inoculación con Enterobacter ludwigii 35V aumentó el contenido de aloína en el gel y en el látex. La investigación adicional debe centrarse en la asociación de estas dos cepas en un solo inoculante, tanto para promover el crecimiento como para aumentar la síntesis de metabolitos

Descripción morfológica y caracterización molecular de los hongos asociados a la raíz de Masdevallia coccinea Linden ex Lindl / Morphological description and molecular characterization of fungi associated with the root of Masdevallia coccinea Linden ex Lindl

RESUMEN Masdevallia coccinea es una orquídea llamativa, endémica de Colombia, empleada en la generación de híbridos ornamentales con más de una década, clasificada como una especie en peligro de extinción. Entre las técnicas usadas para la propagación in vitro y ex situ de especies de la familia Orchidaceae, se estudia la simbiosis micorrízica, debido a que esta familia micoheterótrofa depende de una correlación con estos hongos para subsistir en las primeras etapas de desarrollo en estado silvestre. Con el objetivo de caracterizar e identificar los hongos asociados a las raíces de M. coccinea, se realizó un estudio histológico en raíces y, a partir de micropreparados, se caracterizó morfológicamente micro, macroscópica y molecularmente diez aislamientos. Se identificó a M. coccinea como una orquídea que presenta diferentes patrones de colonización micorrízicos y con posibles efectos endófitos de los géneros Aspergillus, Scopulariopsis, Trichoderma, Ilyonectria y del orden Xylariales en condiciones ex situ.

ABSTRACT Masdevallia coccinea is a striking orchid, endemic to Colombia, used in the generation of ornamental hybrids, with more than a decade classified as an endangered species. Among the techniques used for in vitro and ex situ propagation of species of the Orchidaceae family, mycorrhizal symbiosis is studied, because this mycoheterotrophic family depends on a correlation with these fungi to survive in the early stages of development in the wild. In order to characterize and identify the fungi associated with the roots of M. coccinea, a histological study was carried out on roots and 10 isolates were morphologically, macroscopically and molecularly characterized from micropreparations. M. coccinea is identified as an orchid with different mycorrhizal colonization patterns and with possible endophytic effects of the genera Aspergillus, Scopulariopsis, Trichoderma, Ilyonectria and the order Xylariales under ex situ conditions.

Secondary metabolites from the dandelion-derived endophytic fungus Epicoccum sorghinum 1-2 / 药学学报

The secondary metabolites from the dandelion-derived Epicoccum sorghinum 1-2 were isolated by silica gel and Sephadex gel column chromatography, and semi-preparative high performance liquid chromatography (HPLC). Their structures were identified by comprehensive NMR and MS methods. Their antibacterial activities were determined by filter paper method. Finally, seven compounds were isolated and identified from the fermentation product of E. sorghinum 1-2, including (4R*,5R*,6S*)-4,5-dihydroxy-6-(6'-methylsalicyloxy)-2-methoxymethyl-2-cyclohexen-l-one (1), (4R*,5R*,6S*)-4,5-dihydroxy-6-(6′-methylsalicyloxy)-2-methyl-2-cyclohexen-1-one (2), (4R,5R,6S)-4,5-dihydroxy-6-(6'-methylsalicyloxy)-2-hydroxymethyl-2-cyclohexen-1-one (3), (-)-gabosine E (4), theobroxide (5), 3-chlorogentisyl alcohol (6), and 3-hydroxybenzyl alcohol (7), of which 1-5 are epoxydons, and 6 and 7 are phenolics. Compounds 1 and 2 are new structures reported for the first time. Compound 6 showed significant antibacterial activity against Staphylococcus aureus.

Mycosynthesis of thermostable silver nanoparticles by the endophytic Albifimbria verrucaria with antimicrobial and antiproliferative activities

Aims@#This study was aimed to screen and isolate soil and endophytic fungi with the ability to biosynthesize stable silver nanoparticles (SNPs) with antimicrobial and antiproliferative activities.@*Methodology and results@#A total of 60 fungal isolates isolated from soil and plant samples were screened for their ability to biosynthesize SNPs. Among which, 21 isolates have supported the biosynthesis of SNPs. Furthermore, the endophytic isolate PRR2.1 synthesized highly thermostable SNPs with long shelf life. The PRR2.1 isolate was identified as Albifimbria verrucaria by morphological and molecular means. The synthesis of SNPs was initially monitored by UV-Vis spectroscopy. Further characterization by transmission electron microscopy, X-ray diffraction and dynamic light scattering revealed well-dispersed spherical crystalline in nature SNPs with a mean size of 14 nm and zeta potential of –24.47 mV. Fourier transform infrared spectroscopy showed the presence of biomolecules adsorbed on the surface of biosynthesized SNPs responsible for their synthesis and stability. The mycosynthesized SNPs exhibited stronger antifungal activity against pathogenic strains of Aspergillus niger, A. flavus, A. fumigatus and Candida albicans with respect to its antibacterial activity against Escherichia coli, Staphylococcus aureus, Bacillus cereus and Klebsiella pneumoniae compared to standard antifungal itraconazole and antibiotic cefadroxil with mostly consistent minimum inhibitory concentration of 5.31 μg/mL. The biosynthesized SNPs demonstrated dose-dependent in vitro antiproliferative activity against cancerous HeLa cell line with IC50 value of 2.52 μg/mL and less cytotoxic activity against WI-38 (normal human lung fibroblasts) cell line with CC50 value of 10.2 μg/mL.@*Conclusion, significance and impact of study@#These results show the potential of endophytic fungi biosynthesized SNPs as possible biofriendly, safe and efficient antimicrobial agents with promising antiproliferative activity and low cytotoxicity, which can be furtherly implemented in various biomedical and biotechnological applications.

Effects of endophytic fungus SH09 on plant growth and accumulation of active components in Salvia miltiorrhiza / 药学实践杂志

Objective To study the effects of endophytic fungus Epichloë bromicola SH09 on the plant growth and accumulation of active components in Salvia miltiorrhiza, and improve the quality of medicinal plant S. miltiorrhiza. Methods E. bromicola SH09 solid bacterial fertilizer was prepared and co-cultured with S. miltiorrhiza for 60 d and 120 d. Four morphological indexes, fresh weight of roots, dry weight of roots, and the contents of four tanshinones and two phenolic acids in the roots of S. miltiorrhiza from treated group and control group were assayed, respectively. Results After 60 d and 120 d co-culture, E. Bromicola SH09 significantly increased the tiller number, plant height, leaf number, leaf area, fresh weight of roots, dry weight of roots, and the content of tanshinones and phenolic acids in S. miltiorrhiz. Conclusion The endophytic fungus E. bromicola SH09 can effectively promote the plant growth and improve the accumulation of active components in S. miltiorrhiza, which not only broadens the new ecological functions of endophytic fungi, but also improves the quality of medicinal plant S. miltiorrhiza.

A new polyketide of endophytic fungi Aspergillus sp. ZJ-58 from Coptis chinensis / 中国中药杂志

A new polyketide, coptaspin A(1), along with two known compounds 4-acetyl-3,4-dihydro-6,8-dihydroxy-3-methoxy-5-methylisocoumarin(2), and cytochalasin Z_(12)(3), was isolated from the endophytic fungi Aspergillus sp. ZJ-58, which was isolated from the genuine medicinal plant Coptis chinensis in Chongqing after solid-state fermentation on rice and silica gel, MCI, and HPLC-based separation. Their structures were elucidated by MS, NMR, IR, UV, and ECD. The newly isolated compound 1 showed moderate inhibitory activities against LPS-induced NO production in RAW264.7 macrophages with the IC_(50) value of 58.7 μmol·L~(-1), suggesting its potential anti-inflammatory activity.

Genome analysis and plant growth promoting activity of Pseudonocardia strain DR1-2 from the root of Dendrobium christyanum Rchb.f

Aims@#The objective of this study was to analyze the genome of endophytic actinomycete associated with orchids and evaluate its plant hormone activities, including phytohormone, siderophore, ammonia production, zinc and phosphate solubilization.@*Methodology and results@#Strain DR1-2 isolated from the roots of the Thai orchid, Dendrobium christyanum Rchb.f., was closely related to Pseudonocardia alni DSM 44104T, P. antarctica DSM 44749T and P. carboxydivorans Y8T (99.93-100% similarity) based 16S rRNA gene sequence. This strain exhibited IAA production (294.10 ± 12.17 μg/mL), phosphate solubilization (2.20 ± 0.08 solubilization Index, SI), positive for siderophore production and ammonia production (36.99 ± 2.24 μg/mL). It showed a maximum IAA of 489.73 ± 8.90 μg/mL, when optimized using 0.5% Ltryptophan, pH 6 and incubated at 30 °C for 7 days. The IAA of strain enhanced the root length, shoot length, number of roots and fresh weight of rice seedlings (Oryza sativa L. cv. RD49). The draft genome of strain DR1-2 was 6,077,423 bp in 23 contigs with G+C content of 74.6%. The average nucleotide identity-Blast (ANIb) and average nucleotide identity-MUMmer (ANIm) values of strain DR1-2 and related type strains were 95.81 to 97.25% and the digital DNA-DNA hybridization (dDDH) values were 72.60 to 74.00%, respectively. Genomic analysis of strain DR1-2 revealed that the gene encodes the enzyme involved in the phytohormones biosynthesis and gene clusters involved in the biosynthesis of bioactive metabolites.@*Conclusion, significance and impact of study@#Endophytic actinomycete, Pseudonocardia strain DR1-2 from Thai orchid, D. christyanum Rchb.f., exhibited significant IAA production and affected the growth of the plant, which was the potential source of plant hormones for agricultural applications.

In vitro screening of siderophore-producing rice root endophytic bacteria from up-land paddies in north-western Vietnam for plant growth-promoting activities

Aims@#Endophytic bacteria (EB) living inside plant tissues possess different beneficial traits including siderophore production and other plant growth-promoting (PGP) activities. Siderophore-producing EB promote host plant growth by secreting ferrum in iron-deficient conditions. This study screened 19 siderophore producers in vitro, isolated from upland rice roots grown in mountain farms of Tung Village, Nậm Có Commune, Mù Cang Chải District, Yên Bái Province, Vietnam, for PGP traits, including phosphate solubilisation, indole-3-acetic acid (IAA), ammonia, gelatinase, amylase and catalase production.@*Methodology and results@#The bacteria were identified by Matrix assisted Laser Desorption Ionization Time of Flight mass spectrometry (MALDI-TOF MS). All 19 isolates were identified as genera Pseudomonas, Enterobacter, Pantoe, Bacillus, Burkholderia, Staphylococcus, Ralstonia and Cronotacter. The isolates produced catalase and ammonia. The amount of ammonia ranged from 60.74 ± 0.14 to 466.72 ± 0.18 mg/L. Out of the 19 siderophore producers, 17 (89.47%) were able to solubilise phosphate with solubilisation index (PSI) ranging from 1.12 ± 0.07 to 2.14 ± 0.15. The qualitative assays identified 12 isolates (63.15%) positive for IAA production with a tryptophan concentration of 5 mM, whereas 15 (78.94%) and 17 (89.47%) isolates were positive for gelatin and starch hydrolysis, respectively. Especially, 7 isolates were found to be positive for all tested assays in vitro including Pseudomonas rhodesiae (NC2), Enterobacter asburiae (NC50), Pantoea ananatis (NC63), Bacillus cereus (NC64), Burkholderia cenocepacia (NC110), Staphylococcus sciuri (NC112) and Ralstonia pickettii (NC122).@*Conclusion, significance and impact of study@#This study serves as crucial findings of multi-trait plant growth-promoting endophytic bacteria isolated from upland rice root in north-western Vietnam. The seven potential isolates positive for all tested assays could be effective PGP bacteria for bio-inoculants.

Endophytic bacteria Bacillus safensis and Pseudomonas hibiscicola and their ability to increase rice seedling growth

Endophytic bacteria Bacillus safensis RS95 and Pseudomonas hibiscicola RS121 were evaluated for their ability to promote the growth of rice seedlings and produce indole-acetic acid (IAA) and siderophores and to solubilize phosphates. 'Guri' rice seeds were immersed in bacterial endophyte cell suspensions (separated and two-strain mixed), as well as in Escherichia coli DH5α, phosphate-buffered saline (PBS) and water treatments (negative controls). Seeds were sown on agar-water in Petri plates placed vertically at an angle of 65°. The ability of plant growth-promoting endophytic bacteria (PGPEB) to produce IAA and siderophores was determined by Salkowski colorimetric and chrome azurol S (CAS) assays, respectively. Mineral phosphate solubilization activity was calculated by inoculating the endophytes onto medium containing insoluble phosphate. PGPEB showed a positive effect on the growth of rice seedlings, causing a mean growth of shoots and primary-roots of 60 and 67%, respectively. Bacterial strains also showed positive traits for IAA and siderophore production, as well as phosphate-solubilization activity

Oxidative stress induction by crude extract of Xylaria sp. triggers lethality in the larvae of Aedes aegypti (Diptera: Culicidae)

ABSTRACT Background: Aedes aegypti is currently controlled with synthetic larvicides; however, mosquitoes have become highly resistant to these larvicides and difficult to eradicate. Studies have shown that insecticides derived from fungal extracts have various mechanisms of action that reduce the risk of resistance in these mosquitoes. One possible mechanism is uncontrolled production of reactive oxygen species (ROS) in the larvae, which can cause changes at the cellular level. Thus, the crude extract of Xylaria sp. was evaluated to investigate the oxidative effect of this extract in A. aegypti larvae by quantifying the oxidative damage to proteins and lipids. Methods: The larvicidal potential of the crude extract of Xylaria sp. Was evaluated, and the extract was subsequently tested in human lung fibroblasts for cytotoxicity and ROS production. ROS level was quantified in the larvae that were killed following exposure to the extract in the larvicide test. Results: The crude extract of Xylaria sp. Caused cytotoxicity and induced ROS production in human lung fibroblasts and A. aegypti larvae, respectively. In the larvicide trial, the extract showed an LC50 of 264.456 ppm and an LC90 of 364.307 ppm, and was thus considered active. The extract showed greater oxidative damage to lipids and proteins, with LC90 values of 24.7 µmol MDA/L and 14.6278 ×10-3 nmol carbonyl/ mg protein, respectively. Conclusions: Crude extracts of Xylaria sp. induced oxidative stress that may have caused the mortality of A. aegypti larvae.