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1.
Fitoterapia ; 173: 105793, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158161

RESUMO

Two novel fungal polyketides, phometides A (1) and B (2), together with four known compounds (3-6), were isolated from the endophytic fungus Phoma sp. YUD17001 obtained from Gastrodia elata Blume. The structures were elucidated based on spectroscopic analyses, X-ray crystal diffraction, and time-dependent density functional theory/electronic circular dichroism (TDDFT/ECD) calculations. Structurally, phometide A (1) represented the first example of C12 polyketide characterized by an unusual tetrahydrobenzofuran-3(2H)-one core with an α,ß-unsaturated ketone functionality, while phometide B (2) was an unprecedented molecule containing a 2-pentylcycloheptan-1-one scaffold. In an antimicrobial activity assay, phometide A (1) exhibited significant inhibitory activity against Staphylococcus aureus with MIC value of 4 µg/mL. Phometide B (2) showed moderate antifungal activity against Candida albicans with an MIC value of 16 µg/mL. Furthermore, compounds 1 and 2 were evaluated for their acetylcholinesterase inhibitory and cytotoxic activities.


Assuntos
Gastrodia , Policetídeos , Estrutura Molecular , Phoma , Acetilcolinesterase , Dicroísmo Circular
2.
Appl Microbiol Biotechnol ; 107(16): 4991-5001, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37401998

RESUMO

The genus Phoma has been explored for a wide range of secondary metabolites signifying a huge range of bioactivities. Phoma sensu lato is a major group that secretes several secondary metabolites. The genus Phoma mainly includes Phoma macrostoma, P. multirostrata, P. exigua, P. herbarum, P. betae, P. bellidis, P. medicaginis, P. tropica, and many more species from the genus that are continuously being identified for their potential secondary metabolites. The metabolite spectrum includes bioactive compounds like phomenon, phomin, phomodione, cytochalasins, cercosporamide, phomazines, and phomapyrone reported from various Phoma spp. These secondary metabolites show a broad range of activities including antimicrobial, antiviral, antinematode, and anticancer. The present review is aimed to emphasize the importance of Phoma sensu lato fungi, as a natural source of biologically active secondary metabolites, and their cytotoxic activities. So far, cytotoxic activities of Phoma spp. have not been reviewed; hence, this review will be novel and useful for the readers to develop Phoma-derived anticancer agents. KEY POINTS: • Different Phoma spp. contain a wide variety of bioactive metabolites. • These Phoma spp. also secrete cytotoxic and antitumor compounds. • The secondary metabolites can be used for the development of anticancer agents.


Assuntos
Antineoplásicos , Phoma , Phoma/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo
3.
Fitoterapia ; 168: 105546, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37217021

RESUMO

Phoma fungi are known to produce a diverse range of natural products which possess various biological activities such as antifungal, antimicrobial, insecticidal, cytotoxic, and immunomodulatory effects. In our present study, we have isolated two novel polyketides (1 and 3), one new sesquiterpenoid (2), and eight known compounds (4-11) from the culture of Phoma sp. 3A00413, a deep-sea sulphide-derived fungus. The structures of compounds 1-3 were elucidated using NMR, MS, NMR calculation, and ECD calculation. In vitro antibacterial activities of all the isolated compounds were evaluated against Escherichia coli, Vibrio parahaemolyticus vp-HL, Vibrio parahaemolyticus, Staphylococcus aureus, Vibrio vulnificus, and Salmonella enteritidis. Compounds 1, 7, and 8 exhibited weak inhibition against Staphylococcus aureus growth, while compounds 3 and 7 showed weak inhibition against Vibrio vulnificus growth. Importantly, compound 3 demonstrated exceptional potency against Vibrio parahaemolyticus, with a minimum inhibitory concentration (MIC) of 3.1 µM.


Assuntos
Phoma , Policetídeos , Sesquiterpenos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Phoma/química , Policetídeos/química , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Bactérias/efeitos dos fármacos
4.
Arch Virol ; 168(4): 103, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36892708

RESUMO

Here, we report a novel mycotombus-like mycovirus, tentatively named "Phoma matteucciicola RNA virus 2" (PmRV2), derived from the phytopathogenic fungus Phoma matteucciicola strain HNQH1. The complete PmRV2 genome is comprised of a positive-sense single-stranded RNA (+ssRNA) of 3,460 nucleotides (nt) with a GC content of 56.71%. Sequence analysis of PmRV2 indicated the presence of two noncontiguous open reading frames (ORFs) encoding a hypothetical protein and an RNA-dependent RNA polymerase (RdRp), respectively. PmRV2 contains a metal-binding 'GDN' triplet in motif C of RdRp, while most +ssRNA mycoviruses contained a 'GDD' motif in the same region. A BLASTp search showed that the RdRp amino acid sequence of PmRV2 was most closely related to the RdRp of Macrophomina phaseolina umbra-like virus 1 (50.72% identity) and Erysiphe necator umbra-like virus 2 (EnUlV2, 44.84% identity). Phylogenetic analysis indicated that PmRV2 grouped together with EnUlV2 within the recently proposed family "Mycotombusviridae".


Assuntos
Micovírus , Vírus de RNA , Phoma , Filogenia , Vírus de RNA/genética , Sequência de Aminoácidos , Micovírus/genética , RNA Polimerase Dependente de RNA/genética , Fases de Leitura Aberta , Genoma Viral , RNA Viral/genética
5.
Phytochemistry ; 201: 113264, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35679970

RESUMO

Ten diphenyl ethers (DPEs), including nine undescribed analogs named betaethrins A-I, were isolated from the desert plant endophytic fungus Phoma betae A.B. Frank (Didymellaceae). Their structures were determined mainly by NMR, HR-ESI-MS spectral and X-ray diffraction experiments. Betaethrins D-I possessed different fatty acid chains connected with the B-ring, which was the first report in all DPEs. The shielding effect of the B-ring on H-6 (A-ring) in methyl barceloneate, betaethrin A and betaethrins D-F (asterric acid analogs) was first observed and analyzed, which could differentiate the 1H-NMR chemical shift values of H-4/H-6 without the assistance of 3-OH. An empirical rule was then suggested: the steric hindrance between the A- and B-rings in asterric acid analogs might prevent these two aromatic rings from rotating freely, which led to the 1H-NMR chemical shift value of H-6 being in the high field zone due to the shielding effect of the B-ring on H-6. Based on the empirical rule, the chemical shift values of the A-ring in methyl barceloneate were revised. The possible biosynthesis of these isolates was postulated. Betaethrin H showed moderate cytotoxicity against MCF-7 and HepG2 cancer cell lines. Betaethrins A-F, H and I displayed strong antioxidant activities. These results further implied that endophytic fungi from unique environments, such as desert plants, with few chemical studies are an important resource of undescribed and bioactive metabolites.


Assuntos
Ascomicetos , Endófitos , Ascomicetos/química , Endófitos/química , Éteres Fenílicos/química , Phoma , Plantas
6.
J Immunol Res ; 2022: 2574964, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35155686

RESUMO

BACKGROUNDS: Infection and inflammation play an important role in prostate cancer (PCa) etiology and pathogenesis. However, the environmental drivers for PCa are not fully understood. METHODS: In a cross-sectional study, we analyzed circulating fungal microbiome in plasma samples from age and race-matched healthy control men (n = 34) and preoperative PCa patients (n = 31). RESULTS: The fungal community in the plasma exhibited differences between individuals with PCa and healthy controls according to the beta diversity; there was no difference in the alpha diversity. Moreover, the relative abundance of several fungi differed between the two study groups from the class to species levels. The most significant differences were Filobasidiales family, Pyronemataceae family, and Cryptococcus ater species, which were enriched in PCa patients compared to controls. The increased Bipolaris genus was associated with low prostate-specific antigen (PSA) levels, increased Sordariomycetes class was associated with severe pathological stage, and decreased Phoma herbarum species was associated with disease relapse, compared to corresponding controls. Several fungi from class to species levels were increased in the controls compared to patients. CONCLUSION: This is the first study to show plasma distinct fungal microbiome and its associations with PSA levels, relapse, and pathology stages in PCa patients.


Assuntos
Bipolaris/fisiologia , Cryptococcus/fisiologia , Phoma/fisiologia , Neoplasias da Próstata/microbiologia , Idoso , Estudos Transversais , Voluntários Saudáveis , Humanos , Masculino , Microbiota/genética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Antígeno Prostático Específico/sangue
7.
Molecules ; 27(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35208971

RESUMO

The aim of our study was to examine the different concentrations of AuNPs as a new antimicrobial substance to control the pathogenic activity. The extracellular synthesis of AuNPs performed by using Phoma sp. as an endophytic fungus. Endophytic fungus was isolated from vascular tissue of peach trees (Prunus persica) from Baft, located in Kerman province, Iran. The UltraViolet-Visible Spectroscopy (UV-Vis spectroscopy) and Fourier transform infrared spectroscopy provided the absorbance peak at 526 nm, while the X-ray diffraction and transmission electron microscopy images released the formation of spherical AuNPs with sizes in the range of 10-100 nm. The findings of inhibition zone test of Au nanoparticles (AuNPs) showed a desirable antifungal and antibacterial activity against phytopathogens including Rhizoctonia solani AG1-IA (AG1-IA has been identified as the dominant anastomosis group) and Xanthomonas oryzae pv. oryzae. The highest inhibition level against sclerotia formation was 93% for AuNPs at a concentration of 80 µg/mL. Application of endophytic fungus biomass for synthesis of AuNPs is relatively inexpensive, single step and environmentally friendly. In vitro study of the antifungal activity of AuNPs at concentrations of 10, 20, 40 and 80 µg/mL was conducted against rice fungal pathogen R. solani to reduce sclerotia formation. The experimental data revealed that the Inhibition rate (RH) for sclerotia formation was (15, 33, 74 and 93%), respectively, for their corresponding AuNPs concentrations (10, 20, 40 and 80 µg/mL). Our findings obviously indicated that the RH strongly depend on AuNPs rates, and enhance upon an increase in AuNPs rates. The application of endophytic fungi biomass for green synthesis is our future goal.


Assuntos
Antibacterianos , Antifúngicos , Biomassa , Endófitos/química , Ouro , Nanopartículas Metálicas/química , Phoma/química , Rhizoctonia/crescimento & desenvolvimento , Xanthomonas/crescimento & desenvolvimento , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Ouro/química , Ouro/farmacologia
8.
Arch Microbiol ; 204(3): 171, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35157131

RESUMO

Melanins are high molecular weight hydrophobic pigments which have gained popularity for their role in virulence against different pathogens. In the present study, we isolated and characterized the melanin pigment produced by a dark septate endophyte fungus Phoma sp. RDSE17, which was associated with the roots of an indigenous Oryza sativa cv. 'Chakhao amubi' in Manipur, Northeast India. The biological properties of purified melanin from the fungus were evaluated for their antioxidant, antimicrobial and anticancerous activities. The pigment was extracted from Phoma sp. by alkaline-acid hydrolysis method and confirmed as melanin through physico-chemical tests and spectral (UV, FTIR, and EPR) analysis. The analyses of the elemental composition indicated that the pigment possessed a low percentage of nitrogen (N) contents, and therefore, would not fall under DOPA class of melanin. Exposure of the fungus to melanin pathway inhibitors revealed a positive melanin inhibition by tricyclazole, but not by kojic acid. Thus, the melanin from Phoma sp. may be a member of the DHN family. Moreover, the purified melanin showed high DPPH (1, 1-Diphenyl-2-picrylhydrazyl) free radical-scavenging activity with an EC50 of 69 µg/mL and inhibited human lung cancer cell (A549 cells) proliferation at 80 µg/mL. The present study demonstrates that melanin from Phoma sp. RDSE17 could be employed as a potential biological (antioxidant) and antimicrobial agent for inhibiting the growth of humans and phytopathogens.


Assuntos
Melaninas , Phoma , Fungos , Humanos , Índia , Pigmentação
9.
Environ Sci Pollut Res Int ; 29(30): 46049-46063, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35157200

RESUMO

Water pollution caused by heavy metals poses a serious threat to the ecosystem and human health. Among the various treatment techniques for water remediation, adsorption is an efficient method due to its high capacity, low cost, and simplicity. Thallium (Tl) is highly toxic to mammals and its removal from water is gaining increasingly prominent attention. In this study, three fungal strains (Fusarium sp. FP, Arthrinium sp. FB, and Phoma sp. FR) were tested for removal of Tl (I) from aqueous solutions and showed excellent removal performance. The prepared inactive fungal strains were characterized by XRD, FT-IR, SEM, and XPS analyses. The effects of pH, contact time, biomass dosage, and reaction temperature on the removal efficiency of Tl (I) were systematically investigated. The results indicated that the adsorption isotherm data fit well with the Langmuir model, and the pseudo-second-order model was more consistent with the kinetic data description. The maximum adsorption capacity of the fungal strain (Fusarium sp. FP, Arthrinium sp. FB, and Phoma sp. FR) for Tl (I) was found to be 94.69 mg/g, 66.97 mg/g, and 52.98 mg/g, respectively. The thermodynamic data showed that the sorption process was spontaneous and endothermic. The present study showed that the inactive fungal strains could be a promising adsorbent material for Tl (I) removal.


Assuntos
Fusarium , Poluentes Químicos da Água , Adsorção , Ecossistema , Humanos , Concentração de Íons de Hidrogênio , Íons , Cinética , Phoma , Espectroscopia de Infravermelho com Transformada de Fourier , Tálio , Água , Poluentes Químicos da Água/análise
10.
Plant Dis ; 106(7): 1857-1866, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35072508

RESUMO

Disease caused by Neocamarosporium betae (syn. Phoma betae, Pleospora betae) results in reductions in plant populations, foliar disease (Phoma leaf spot [PLS]), and root disease and decay in table beet. Disease caused by N. betae has reemerged as prevalent in organic table beet production in New York. The disease can also cause substantial issues in conventional table beet production. To evaluate in-field control options for conventional and organic table beet production, small-plot, replicated trials were conducted in each of two years (2019 and 2021). The fungicides, propiconazole and difenoconazole, and premixtures, pydiflumetofen + fludioxonil or pydiflumetofen + difenoconazole, provided excellent PLS and root decay control. Azoxystrobin provided excellent (69.9%) control of PLS in 2019 and lesser (40%) control in 2021. Field trial results complemented in vitro sensitivity testing of 30 New York N. betae isolates that were all highly sensitive to azoxystrobin (mean effective concentration to reduce mycelial growth by 50%, EC50 = 0.0205 µg/ml) and propiconazole (mean EC50 = 0.0638 µg/ml). Copper octanoate and microbial biopesticides containing either Bacillus amyloliquefaciens D747 or B. mycoides strain J provided moderate (68.5 to 74.6%) PLS control as reflected in epidemic progress. The Gompertz model provided the best fit to PLS epidemics reflecting a polycyclic epidemic. Reductions in PLS severity were associated with significant decreases in Phoma root decay and increases in canopy health and the time-to-death of leaves compared with nontreated control plots. Prolonging leaf survival is critical for mechanical harvest of roots. These findings underpin the design of programs for foliar disease control in conventional and organic table beet production. Assessment of PLS severity in the field will better inform postharvest management decisions.


Assuntos
Beta vulgaris , Ascomicetos , New York , Phoma , Doenças das Plantas/prevenção & controle
11.
Nat Prod Res ; 36(21): 5584-5590, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34965790

RESUMO

A new oxazole-type compound (1), named macrooxazole E, and three known macrooxazoles A-C (2-4), were isolated from ethyl acetate (EtOAc) extracts of Phoma sp. JS0228 cultures, an endophytic fungus of Morus alba (M. alba). Structures of the isolated compounds were determined using spectroscopic methods, such as 1 D- and 2 D-nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). Macrooxazole E (1) differed from macrooxazole C only in the presence of methyl carboxylate instead of free carboxylic acid. Macrooxazole C showed moderate anti-proliferative activities against human breast cancer (MCF-7) and prostate cancer (LNCaP) cell lines with IC50 values of 0.29 mM and 0.36 mM, respectively. This study presents the possibility of the endophytic fungus Phoma sp. JS0228 to produce new bioactive natural compounds.


Assuntos
Morus , Phoma , Humanos , Fungos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Estrutura Molecular
12.
Chem Biodivers ; 19(1): e202100608, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34786852

RESUMO

A new globoscinic acid derivative, aspertubin A (1) along with four known compounds, were obtained from the co-culture of Aspergillus tubingensis S1120 with red ginseng. The chemical structures of compounds were characterized by using spectroscopic methods, the calculated and experimental electronic circular dichroism. Panaxytriol (2) from red ginseng, and asperic acid (4) showed significant antifeedant effect with the antifeedant rates of 75 % and 80 % at the concentrations of 50 µg/cm2 . Monomeric carviolin (3) and asperazine (5) displayed weak attractant activity on silkworm. All compounds were assayed for antifungal activities against phytopathogens A. tubingensis, Nigrospora oryzae and Phoma herbarum and the results indicated that autotoxic aspertubin A (1) and panaxytriol (2) possessed selective inhibition against A. tubingensis with MIC values at 8 µg/mL. The co-culture extract showed higher antifeedant and antifungal activities against P. herbarum than those of monoculture of A. tubingensis in ordinary medium. So the medicinal plant and endophyte showed synergistic effect on the plant disease resistance by active compounds from the coculture of A. tubingensis S1120 and red ginseng.


Assuntos
Antifúngicos/química , Aspergillus/química , Repelentes de Insetos/química , Panax/química , Animais , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Bombyx/efeitos dos fármacos , Bombyx/crescimento & desenvolvimento , Enedi-Inos/química , Enedi-Inos/isolamento & purificação , Enedi-Inos/farmacologia , Álcoois Graxos/química , Álcoois Graxos/isolamento & purificação , Álcoois Graxos/farmacologia , Repelentes de Insetos/isolamento & purificação , Repelentes de Insetos/farmacologia , Testes de Sensibilidade Microbiana , Conformação Molecular , Panax/crescimento & desenvolvimento , Panax/metabolismo , Phoma/efeitos dos fármacos , Plantas Medicinais/química , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/metabolismo
13.
Nat Prod Res ; 36(15): 4003-4008, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33719740

RESUMO

A new tyrosine derivative (1), and two new terezine derivatives (2 and 3) were discovered from a marine-sponge-derived fungus Phoma herbarum YG5839. Those compounds were identified by comprehensive spectroscopic analysis, and antifungal activities were conducted against Fusarium oxysporum, Fusarium graminearum, Penicillium italicum, Colletotrictum gloeosporioides and Colletotrichum musae.


Assuntos
Phoma , Tirosina , Antifúngicos/química , Antifúngicos/farmacologia
14.
Lett Appl Microbiol ; 73(4): 515-528, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34263965

RESUMO

The process parameters were optimized to obtain enhanced enzyme activity from the fungus Phoma herbarum isolate KU4 using rice straw and saw dust as substrate under solid-state fermentation using Response surface methodology (RSM). Genetic algorithm was used to validate the RSM for maximum laccase production. Six variables, viz., pH of the media, initial moisture content, copper sulphate concentration, concentration of tannic acid, inoculum concentration and incubation time were found to be effective and optimized for enhanced production. Maximum laccase production was achieved by RSM at pH 5·0 and 86% of initial moisture content of the culture medium, 150 µmol l-1 of CuSO4 , 1·5% tannic acid and 0·128 g inoculum g-1 dry substrate inoculum size on the fourth day of fermentation. The highest laccase activity was observed as 79 008 U g-1 , which is approximately sixfold enhanced production compared to the unoptimized condition (12 085·26 U g-1 ).


Assuntos
Lacase , Phoma , Algoritmos , Meios de Cultura , Fermentação
15.
Sci Rep ; 11(1): 7637, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33828138

RESUMO

Global warming has led to frequent droughts, posing challenges for afforestation in arid and semiarid regions. In search of labor-saving and money-saving methods to improve the survival and growth rates of trees in these regions, we isolated and identified fungal endophytes that can potentially enhance the drought-resistance abilities of seedlings. We isolated 93 endophytic strains from the roots of Pinus tabulaeformis trees grown on an arid cliff. Three isolates increased the drought resistance of the tree seedlings. Using morphological, molecular, and physiological-biochemical methods, we identified three isolates as different clones of a strain of Phoma spp. and studied the strain's effect on stress resistance-related substances in the seedlings. The results showed that the strain improved drought tolerance and increased the seedlings' proline levels and antioxidant enzyme activities. The strain also secreted abundant extracellular abscisic acid, which likely triggered the seedlings' protective mechanisms. This endophytic strain may provide a cheaper labor-saving, sustainable alternative to traditional methods of enhancing drought resistance.


Assuntos
Phoma/metabolismo , Pinus/microbiologia , Estresse Fisiológico/fisiologia , China , Secas , Endófitos/metabolismo , Micoses , Pinus/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Plântula/microbiologia , Simbiose/fisiologia , Árvores/microbiologia
16.
Appl Microbiol Biotechnol ; 105(8): 3009-3018, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33770245

RESUMO

Modern agriculture has been facing new challenges and fostering innovations to establish sustainable plant production. An integral part of these strategies is implementing new eco-friendly technologies in plant protection for better human health and a safer environment by minimizing the use of hazardous chemicals and also encouraging innovations such as the use of bio-based strategies for weed control. This specific strategy addresses the need to reduce the use and risk of pesticides, replacing conventional chemical herbicides with new bio-based solutions. In response to these issues, biocontrol strategies are gaining increased attention from stakeholders such as farmers, seed companies, agronomists, breeders, and consumers. Among these, bioherbicides have huge potential for the management of harmful weeds without affecting the natural quality of the environment and human health. In this context, this review is devoted to present an overview of the mycoherbicidal potential of Phoma sensu lato group of fungi, examining the advances in this field, including technological and scientific challenges and outcomes achieved in recent years. The mycoherbicides are eco-friendly and economically viable. KEY POINTS: • Some Phoma species have demonstrated herbicide activity. • These species secrete secondary metabolites responsible for the control of weeds. • They can be used as non-chemical, cost-effective, and eco-friendly bioherbicides.


Assuntos
Herbicidas , Phoma , Agricultura , Humanos , Plantas Daninhas , Controle de Plantas Daninhas
17.
Planta ; 253(4): 78, 2021 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-33715081

RESUMO

MAIN CONCLUSION: The in vitro application of rhizosphere microorganisms led to a higher rooting percentage in Pyrus Py12 rootstocks and increased plant growth of Pyrus Py170 and Prunus RP-20. The rooting of fruit tree rootstocks is the most challenging step of the in vitro propagation process. The use of rhizosphere microorganisms to promote in vitro rooting and plant growth as an alternative to the addition of chemical hormones to culture media is proposed in the present study. Explants from two Pyrus (Py170 and Py12) rootstocks and the Prunus RP-20 rootstock were inoculated with Pseudomonas oryzihabitans PGP01, Cladosporium ramotenellum PGP02 and Phoma sp. PGP03 following two different methods to determine their effects on in vitro rooting and plantlet growth. The effects of the microorganisms on the growth of fully developed Py170 and RP-20 plantlets were also studied in vitro. All experiments were conducted using vermiculite to simulate a soil system in vitro. When applied to Py12 shoots, which is a hard-to-root plant material, both C. ramotenellum PGP02 and Phoma sp. PGP03 fungi were able to increase the rooting percentage from 56.25% to 100% following auxin indole-3-butyric acid (IBA) treatment. Thus, the presence of these microorganisms clearly improved root development, inducing a higher number of roots and causing shorter roots. Better overall growth and improved stem growth of treated plants was observed when auxin treatment was replaced by co-culture with microorganisms. A root growth-promoting effect was observed on RP-20 plantlets after inoculation with C. ramotenellum PGP02, while P. oryzihabitans PGP01 increased root numbers for both Py170 and RP-20 and increased root growth over stem growth for RP-20. It was also shown that the three microorganisms P. oryzihabitans PGP01, C. ramotenellum PGP02 and Phoma sp. PGP03 were able to naturally produce auxin, including indole-3-acetic acid (IAA), at different levels. Overall, our results demonstrate that the microorganisms P. oryzihabitans PGP01 and C. ramotenellum PGP02 had beneficial effects on in vitro rooting and plantlet growth and could be applied to in vitro tissue culture as a substitute for IBA.


Assuntos
Cladosporium/fisiologia , Raízes de Plantas/fisiologia , Prunus/fisiologia , Pseudomonas/fisiologia , Pyrus/fisiologia , Phoma/fisiologia , Raízes de Plantas/microbiologia , Prunus/microbiologia , Pyrus/microbiologia , Rizosfera , Microbiologia do Solo
18.
Chem Biodivers ; 18(3): e2000964, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33533151

RESUMO

Endophytic fungi play important roles for host's stress tolerance including invasion by pathogenic microbes. Small molecules are common weapons in the microbe-microbe interactions. Panax notoginseng is a widely used traditional Chinese medicinal plant and harbors many endophytes, some exert functions against pathogens. Here, we report six new compounds named myrothins A-F (1-6) produced by Myrothecium sp. BS-31, an endophyte isolated from P. notoginseng, and their antifungal activities against pathogenic fungi causing host root-rot disease. Their structures were elucidated with analysis of spectroscopic data including 1D and 2D NMR, HR-ESI-MS. Myrothins B (2) and E (5) showed the weak activity against Fusarium oxysporum and Phoma herbarum, and myrothins F (6) showed weak activity against F. oxysporum.


Assuntos
Antifúngicos/farmacologia , Endófitos/química , Hypocreales/química , Panax notoginseng/microbiologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Relação Dose-Resposta a Droga , Fusarium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Phoma/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
19.
Sci Rep ; 11(1): 3810, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589671

RESUMO

Phoma stem canker (caused by the ascomycetes Leptosphaeria maculans and Leptosphaeria biglobosa) is an important disease of oilseed rape. Its effect on endophyte communities in roots and shoots and the potential of endophytes to promote growth and control diseases of oilseed rape (OSR) was investigated. Phoma stem canker had a large effect especially on fungal but also on bacterial endophyte communities. Dominant bacterial genera were Pseudomonas, followed by Enterobacter, Serratia, Stenotrophomonas, Bacillus and Staphylococcus. Achromobacter, Pectobacter and Sphingobacterium were isolated only from diseased plants, though in very small numbers. The fungal genera Cladosporium, Botrytis and Torula were dominant in healthy plants whereas Alternaria, Fusarium and Basidiomycetes (Vishniacozyma, Holtermaniella, Bjerkandera/Thanatephorus) occurred exclusively in diseased plants. Remarkably, Leptosphaeria biglobosa could be isolated in large numbers from shoots of both healthy and diseased plants. Plant growth promoting properties (antioxidative activity, P-solubilisation, production of phytohormones and siderophores) were widespread in OSR endophytes. Although none of the tested bacterial endophytes (Achromobacter, Enterobacter, Pseudomonas, Serratia and Stenotrophomonas) promoted growth of oilseed rape under P-limiting conditions or controlled Phoma disease on oilseed rape cotyledons, they significantly reduced incidence of Sclerotinia disease. In the field, a combined inoculum consisting of Achromobacter piechaudii, two pseudomonads and Stenotrophomonas rhizophila tendencially increased OSR yield and reduced Phoma stem canker.


Assuntos
Brassica napus/microbiologia , Endófitos/crescimento & desenvolvimento , Doenças das Plantas/genética , Raízes de Plantas/genética , Achromobacter/genética , Achromobacter/crescimento & desenvolvimento , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Brassica napus/genética , Brassica napus/crescimento & desenvolvimento , Resistência à Doença/genética , Endófitos/genética , Micobioma/genética , Phoma/genética , Phoma/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Stenotrophomonas/genética , Stenotrophomonas/crescimento & desenvolvimento
20.
Prep Biochem Biotechnol ; 51(9): 901-918, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33586595

RESUMO

Production of an extracellular thermophilic and alkali stable laccase from Phoma herbarum isolate KU4 was reported for the first time, both in submerged fermentation (SmF, highest 1590 U/mL) and solid state fermentation (SSF, highest 2014.21 U/mL) using agro-industrial residues. The laccase was partially purified to 7.93 fold with the apparent molecular weight of 298 kDa. The enzyme had pH optimum at 5.0 and temperature optimum at 50 °C, with maximum stability at pH 8.0. It showed activity towards various phenolic and non-phenolic compounds. The kinetic parameters, Km, Vmax and Kcat of the laccase for DMP were 0.216 mM, 270.27 U/mg and 506.69 s-1, respectively. Laccase activity was inhibited by various metal ions and conventional inhibitors, however, it was slightly increased by Zn2+. The laccase showed good decolorization efficiency towards four industrial dyes, namely, methyl violet (75.66%), methyl green (65%), indigo carmine (58%) and neutral red (42%) within 24 h. FTIR analysis of the decolorized products confirmed the degradation of the dyes. The decolorization efficiency of the enzyme suggests that the partially purified laccase could be used to decolorize synthetic dyes present in industrial effluents and for waste water treatments. The thermophilic and alkali stable laccase may also have wider potential industrial applications.


Assuntos
Corantes/química , Proteínas Fúngicas , Temperatura Alta , Lacase , Phoma/enzimologia , Estabilidade Enzimática , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Concentração de Íons de Hidrogênio , Lacase/química , Lacase/isolamento & purificação
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