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1.
Curr Microbiol ; 79(6): 159, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35416548

RESUMO

The role of the most fungal endophytes in the host plant growth and production of metabolites under stress conditions is still unknown. Fungal endophytes occur in almost all plants to benefit the host plants exposed to biotic and abiotic stress. In the present work, we investigated salt (NaCl) stress alleviation capability of a fungal endophyte (Porostereum spadiceum-AGH786). The culture filtrate (CF: 1.5 mL.) of P. spadiceum-AGH786 contained IAA (158 µg/ml), SA (29.3 µg/ml), proline (114.6 µg/ml), phenols (167.4 µg/ml), lipids (71.4 µg/ml), sugar (133.2 µg/ml), flavonoids (105.04 µg/ml). Smaller amounts of organic acids, such as butyric acid (5.8 µg/ml), formic acid (2.34 µg/ml), succinic acid (2.02 µg/ml), and quinic acid (2.25 µg/ml) were also found in CF of P. spadiceum-AGH786. Similarly, the CF displayed antioxidant activity in 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. Moreover, wheat plants colonized by P. spadiceum-AGH786 showed significantly (P = 0.05) higher polyphenol oxidases activity (2.2 mg/g DW) under normal conditions as compared to the NaCl-treated plants. We also observed that P. spadiceum-AGH786 improved biomass (0.30 g) of wheat plants subjected to 140 mM NaCl stress. The results conclude that the wheat plant colonization by P. spadiceum-AGH786 greatly improved the plant growth under 70 mM and 140 mM NaCl stress. Thus, the biomass of the P. Spadiceum-AGH786 can be used in saline soil to help the host plants.


Assuntos
Polyporales , Triticum , Estresse Salino , Cloreto de Sódio/metabolismo , Triticum/metabolismo
2.
Ecotoxicol Environ Saf ; 206: 111381, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33011512

RESUMO

Today's world needs to control the industrial pollution through smarter ways. Presently, we observed the capacity of soil borne fungi to digest Synozol Red HF-6BN and Synozol Black B. Initially, 86 fungal strains were isolated from soil samples randomly collected from industrial sites. Among these, 31 isolates were capable of dye decolorization on solid media, with SN12f and SN13a isolates showed the highest decolorization capacity. The dye decolorization by both strains was higher (80-95%), when incubated for 120 h under optimized conditions of pH, concentration, nutrient source and temperature. The dye (Synozol red HF-6BN and Synozol black B) decolorization by SN12f isolate was maximum (˃90%) at pH7, whereas the SN13a decolorized 90% of Synozol red HF-6BN and 89% of Synozol black B at pH3. The SN13a and SN12f isolates at 40 mg/L showed de-colorization of 94.71%, 81.4% (for Synozol red HF-6BN) and 90.5%, 84.4% (Synozol black B), respectively. Our isolates also mitigated the toxic effect of azo dyes on the growth of phosphate solubilizing soil bacteria. In fact, the untreated effluent showed toxic effects on the growth of beneficial bacterial by developing zone of inhibition (16.5 mm around Aeromonas spp., 14.5 mm around Sallmonella while 14.25 mm around Citrobacter spp). However, the fungal treated dye was unable to develop zone of inhibition. Laccase activity was positive for both of fungal isolates after incubation on Bassnell Hass Medium (0.0733 U/mL for SN12f and 0.0439 U/mL SN13a). Using molecular approaches (ITS region), SN12f was identified as Aspergillus nidulans, while SN13a as Aspergillus fumigatus. The current study showed that local fungal flora can reclaim the contaminated soils and support the agro-friendly micro-flora.


Assuntos
Compostos Azo/metabolismo , Fungos/metabolismo , Microbiologia do Solo , Descoloração da Água/métodos , Poluentes Químicos da Água/metabolismo , Aspergillus/isolamento & purificação , Aspergillus/metabolismo , Compostos Azo/toxicidade , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental , Fungos/isolamento & purificação , Concentração de Íons de Hidrogênio , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade
3.
Biochem J ; 475(18): 2893-2905, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30127090

RESUMO

Flooding is an abiotic stress that creates hypoxic conditions triggered by redox potential leading to restricted growth and grain yield in plants. In the current study, we have investigated the effect of exogenous gibberellins (GA4+7) on soybean under flooding stress. A regulatory role of GAs on biochemical changes in soybean plants [including chlorophyll contents, endogenous bioactive GA1 and GA4, endogenous jasmonic acid (JA) and abscisic acid (ABA)] has been elucidated after 3 and 6 h of flooding stress. The modulation of stress-related bio-chemicals and their genetic determinants [for instance, ABA (Timing of CAB expression1-TOC1, ABA-receptor-ABAR) and NO (S-nitrosoglutathione reductase-GSNOR1, NO overproducer1-NOX, and nitrite reductase-NR)] in response to short-term flooding stress were also explored. The current study showed that exogenous GAs rescued chlorophyll contents, enhanced endogenous bioactive GA1 and GA4 levels, endogenous jasmonic acid (JA) and checked the rate of ABA biosynthesis under short-term flooding. The exo-GAs induced the glutathione activity and reduced the resulting superoxide anion contents during short-term flooding in Pungsannamul soybean. Exo-GAs also triggered the endogenous S-nitrosothiols (precursor for increased NO production) that have been decreased over the time. Moreover, the exo-GAs could impinge a variety of biochemical and transcriptional programs that are ameliorative to plant growth during short-term flooding stress. The presence of GA1 and GA4 also confirms the presence of both C13-hydroxylation pathway and non-C13-hydroxylation pathway in soybean, respectively.


Assuntos
Giberelinas/farmacologia , Glycine max/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Ácido Abscísico/metabolismo , Clorofila/metabolismo , Ciclopentanos/metabolismo , Oxilipinas/metabolismo
4.
Arch Microbiol ; 199(5): 691-700, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28220202

RESUMO

Fungal endophytes establish an important niche within the host plant through the secretion of chemical constituents. Isolation of bioactive metabolites could be a vital source for inhibiting the function of enzymes such as α-glucosidase and urease. The present study aimed to elucidate the potential of endophytes associated with Boswellia sacra through bioassay-guided isolation and identification of secondary metabolites with enzyme inhibitory ability. Endophytic fungal strains viz. Penicillium citrinum, P. spinulosum, Fusarium oxysporum, Alternaria alternata and Aspergillus caespitosus were identified through genomic DNA extraction, PCR amplification, sequencing and phylogenetic analysis. The enzymes inhibition analysis of the ethyl acetate extract from pure cultures suggested that P. citrinum possess significantly higher enzyme inhibitory activities compared to other strains. The active strain was subjected to chromatographic isolation and nuclear magnetic resonance methods to identify bioactive compounds. The bioactive extracts resulted in the isolation of 11-oxoursonic acid benzyl ester (1), n-nonane (2), 3-decene-1-ol (3), 2-Hydroxyphenyl acetic acid (4), and Glochidacuminosides A (5). Among pure compound, 11-oxoursonic acid benzyl ester (1) showed significantly higher enzyme inhibition activity compared to other metabolites. Our results suggest that the endophytic microorganism associated with the arid-land tree can offer a rich source of biologically active chemical constituents that could help discover lead drugs for enzyme inhibition.


Assuntos
Alternaria/metabolismo , Aspergillus/metabolismo , Boswellia/microbiologia , Fusarium/metabolismo , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Penicillium/metabolismo , Urease/antagonistas & inibidores , alfa-Glucosidases/metabolismo , Alternaria/classificação , Alternaria/isolamento & purificação , Aspergillus/classificação , Aspergillus/isolamento & purificação , Endófitos/isolamento & purificação , Fusarium/classificação , Fusarium/isolamento & purificação , Penicillium/classificação , Penicillium/isolamento & purificação , Filogenia , Folhas de Planta/microbiologia , Caules de Planta/microbiologia , Metabolismo Secundário
5.
Microorganisms ; 11(2)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838475

RESUMO

Lipases are versatile biocatalysts and are used in different bioconversion reactions. Microbial lipases are currently attracting a great amount of attention due to the rapid advancement of enzyme technology and its practical application in a variety of industrial processes. The current review provides updated information on the different sources of microbial lipases, such as fungi, bacteria, and yeast, their classical and modern purification techniques, including precipitation and chromatographic separation, the immunopurification technique, the reversed micellar system, aqueous two-phase system (ATPS), aqueous two-phase flotation (ATPF), and the use of microbial lipases in different industries, e.g., the food, textile, leather, cosmetics, paper, and detergent industries. Furthermore, the article provides a critical analysis of lipase-producing microbes, distinguished from the previously published reviews, and illustrates the use of lipases in biosensors, biodiesel production, and tea processing, and their role in bioremediation and racemization.

6.
Microorganisms ; 11(3)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36985276

RESUMO

Industrial effluents result in water pollution and affect the biological activity of aquatic and terrestrial life. In this study, efficient fungal strains were isolated from the aquatic environment and identified as Aspergillus fumigatus (SN8c) and Aspergillus terreus (SN40b). The isolates were selected based on their potential to efficiently decolorize and detoxify Remazol brilliant blue (RBB) dye, which is extensively used in different industries. Initially, a total of 70 different fungal isolates were screened. Among these, 19 isolates demonstrated dye decolorization capabilities, and SN8c and SN40b revealed the highest decolorization capabilities in liquid medium. The maximum estimated decolorization for SN8c was 91.3% and for SN40b, 84.5% at 40 mg/L of RBB dye in the presence of glucose (1 gm/L), after 5 days of incubation at different levels of pH, temperature, nutrient source, and concentration. RBB dye decolorization using SN8c and SN40b isolates was at a maximum of 99% at pH 3-5, whereas minimum decolorization was recorded as 71.29% and 73.4% SN8c, respectively, at pH 11. The maximum decolorization of the dye was 93% and 90.9% in a defined glucose concentration of 1 gm/L, and a 63.01% decrease was recorded in the decolorization activity at a low level of glucose concentration (0.2 gm/L). Finally, the decolorization and degradation were detected using UV spectrometry and HPLC. Toxicity tests of pure dye and treated dye samples were checked against the seed germination of different plants and the larvae mortality of Artemia salina. This study revealed that indigenous aquatic fungal flora can recover contaminated sites and support aquatic and terrestrial life.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37999897

RESUMO

Microbial alkaline proteases are dominating the global enzyme market with a share of over 65% due to their multifarious catalytic potentials. Hence, production of proteases with novel properties of commercial significance is highly desirable to meet the global enzyme demand. Here, we report the purification, characterization, and pilot-scale application of a serine protease from the desert soil bacterium Bacillus subtilis ZMS-2 with novel properties as dehairing agent in leather processing. The enzyme was purified 16.5-fold with a specific activity of 1543.5 U mg-1 and recovery percentage of 33.6% using ammonium sulfate precipitation, ion exchange, and gel filtration chromatography. The purified enzyme was characterized as a metal ion-, surfactant-, and denaturant-compatible alkaline serine protease having a molecular weight of 36.1 kDa with an optimum activity at pH 8.5 and 60 °C. The catalytic activity of the enzyme was enhanced by Zn+2 (204%), Ag+ (110%), H2O2 (123%), Triton X-100 (110%), iso-octane (109%), chloroform (110%), ethanol (105%), ethyl acetate (110%), and acetonitrile (128%). During pilot-scale applications, the optimum condition was found to be a combination of enzyme (1.5%, 460 U mL-1), sodium sulfide (2%), and calcium hydroxide (lime) (3%). Under this condition, the time required for complete dehairing was 90 min. Chemoenzymatically processed skins exhibited better physical properties than chemically processed skin, including tensile strength (16.35 ± 6.68 N/mm), ball burst (452.88 ± 6.06 N/mm), percent elongation (38.85 ± 1.06 N), tear strength (50.16 ± 4.42 N/mm), and softness (6.5 mm). Electron microscopy analysis of the treated skin showed complete removal of hairs with roots, confirming the keratin specificity of the enzyme. Moreover, the enzyme-assisted dehairing process reduced chemical oxygen demand (COD), biochemical oxygen demand (BOD), total dissolved solids (TDS), and total suspended solids (TSS) by 68, 77, 34, and 39%, respectively. Thus, the alkaline serine protease from B. subtilis ZMS-2 is a potential dehairing agent for the eco-friendly processing of animal skins on industrial scales.

8.
Plants (Basel) ; 12(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37111926

RESUMO

Abiotic stressors are global limiting constraints for plant growth and development. The most severe abiotic factor for plant growth suppression is salt. Among many field crops, maize is more vulnerable to salt, which inhibits the growth and development of plants and results in low productivity or even crop loss under extreme salinity. Consequently, comprehending the effects of salt stress on maize crop improvement, while retaining high productivity and applying mitigation strategies, is essential for achieving the long-term objective of sustainable food security. This study aimed to exploit the endophytic fungal microbe; Aspergillus welwitschiae BK isolate for the growth promotion of maize under severe salinity stress. Current findings showed that salt stress (200 mM) negatively affected chlorophyll a and b, total chlorophyll, and endogenous IAA, with enhanced values of chlorophyll a/b ratio, carotenoids, total protein, total sugars, total lipids, secondary metabolites (phenol, flavonoids, tannins), antioxidant enzyme activity (catalase, ascorbate peroxidase), proline content, and lipid peroxidation in maize plants. However, BK inoculation reversed the negative impact of salt stress by rebalancing the chlorophyll a/b ratio, carotenoids, total protein, total sugars, total lipids, secondary metabolites (phenol, flavonoids, tannins), antioxidant enzyme activity (catalase, ascorbate peroxidase), and proline content to optimal levels suitable for growth promotion and ameliorating salt stress in maize plants. Furthermore, maize plants inoculated with BK under salt stress had lower Na+, Cl- concentrations, lower Na+/K+ and Na+/Ca2+ ratios, and higher N, P, Ca2+, K+, and Mg2+ content than non-inoculated plants. The BK isolate improved the salt tolerance by modulating physiochemical attributes, and the root-to-shoot translocation of ions and mineral elements, thereby rebalancing the Na+/K+, Na+/Ca2+ ratio of maize plants under salt stress.

9.
Curr Pharm Des ; 29(41): 3324-3339, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111115

RESUMO

INTRODUCTION: In the present study, we aimed to investigate the extraction and identification of the potential phytochemicals from the Methanolic Extract of Dryopteris ramosa (MEDR) using GC-MS profiling for validating the traditional uses of MEDR its efficacy in inflammations by using in-vitro, in-vivo and in silico approaches in anti-inflammatory models. METHODS: GC-MS analysis confirmed the presence of a total of 59 phytochemical compounds. The human red blood cells (HRBC) membrane stabilization assay and heat-induced hemolysis method were used as in-vitro anti-inflammatory activity of the extract. The in-vivo analysis was carried out through the Xylene-induced mice ear oedema method. It was found that MEDR at a concentration of 20 µg, 30 µg, and 40 µg showed 35.45%, 36.01%, and 36.33% protection to HRBC in a hypotonic solution, respectively. At the same time, standard Diclofenac at 30 µg showed 45.31% protection of HRBC in a hypotonic solution. RESULTS: The extract showed inhibition of 25.32%, 26.53%, and 33.31% cell membrane lysis at heating at 20 µg, 30 µg, and 40 µg, respectively. In comparison, standard Diclofenac at 30 µg showed 50.49% inhibition of denaturation to heat. Methanolic extract of the plant exhibited momentous inhibition in xylene-induced ear oedema in mice treated with 30 µg extract were 47.2%, 63.4%, and 78.8%, while inhibition in mice ear oedema treated with 60 µg extract was 34.7%, 43.05%, 63.21% and reduction in ear thickness of standard drug were 57.3%, 59.54%, 60.42% recorded at the duration of 1, 4 and 24 hours of inflammation. Molecular docking and simulations were performed to validate the anti-inflammatory role of the phytochemicals that revealed five potential phytochemicals i.e. Stigmasterol,22,23dihydro, Heptadecane,8methyl, Pimaricacid, Germacrene and 1,3Cyclohexadiene,_5(1,5dimethyl4hexenyl)-2methyl which revealed potential or significant inhibitory effects on cyclooxygenase-2 (COX-2), tumour necrosis factor (TNF-α), and interleukin (IL-6) in the docking analysis. CONCLUSION: The outcome of the study signifies that MEDR can offer a new prospect in the discovery of a harmonizing and alternative therapy for inflammatory disease conditions.


Assuntos
Dryopteris , Camundongos , Humanos , Animais , Xilenos/efeitos adversos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Simulação de Acoplamento Molecular , Diclofenaco/efeitos adversos , Soluções Hipotônicas/efeitos adversos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , Edema/induzido quimicamente , Edema/tratamento farmacológico , Metanol/efeitos adversos , Fator de Necrose Tumoral alfa
10.
World J Microbiol Biotechnol ; 28(4): 1483-94, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22805930

RESUMO

Little is known about the role of endophytic fungi against abiotic stresses and isoflavonoids (IF) contents of soybean. In current study, we investigated the role of fungal endophytes on the growth of soybean under salt stress conditions. Pure cultures of nine endophytic fungi were isolated from the roots of field-grown soybean plants, and their culture filtrates were screened on Waito-C and Dongjin-byeo rice cultivars; for identification of plant growth promoting fungal strains. It was observed that fungal isolate GMC-2B significantly promoted the growth of both Waito-C and Dongjin-byeo. GMC-2B was later identified as a new strain of Metarhizium anisopliae LHL07 on the basis of 18S rDNA sequences and phylogenetic analysis. Metarhizium anisopliae LHL07 inoculated soybean plants recorded significantly higher shoot length, shoot fresh and dry biomass, chlorophyll contents, transpiration rate, photosynthetic rate and leaf area; under sodium chloride induced salt stress as compared to non-inoculated control plants. An elevated proline and reduced superoxide dismutase and malondialdehyde contents in M. anisopliae LHL07 inoculated soybean plants demonstrated mitigation of salt induced oxidative stress. Furthermore, reduced abscisic acid and elevated jasmonic acid contents in soybean plants confirmed that lesser stress was convened to M. anisopliae inoculated-plants under salinity stress. We also assessed the role of M. anisopliae interaction on IF biosynthesis of soybean, and found significantly higher IF contents in M. anisopliae inoculated soybean plants. In conclusion, endophytic fungal interactions with soybean can be beneficial to improve soybean quality and quantity under salt affected agricultural systems.


Assuntos
Glycine max/crescimento & desenvolvimento , Glycine max/microbiologia , Metarhizium/crescimento & desenvolvimento , Pressão Osmótica , Sais/toxicidade , Biomassa , Clorofila/análise , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Endófitos/crescimento & desenvolvimento , Endófitos/metabolismo , Genes de RNAr , Malondialdeído/análise , Metarhizium/metabolismo , Dados de Sequência Molecular , Fotossíntese , Filogenia , Reguladores de Crescimento de Plantas/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Transpiração Vegetal , Prolina/análise , RNA Fúngico/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Glycine max/química , Glycine max/fisiologia , Superóxido Dismutase/análise
11.
Biomed Res Int ; 2022: 2461021, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36567913

RESUMO

Plant species are known to harbor large number of endophytes, which stays in plant tissues as symbionts. These endophytes secrete large array of bioactive compounds that have potency against certain diseases with no side effects. We have collected leaf samples of the Moringa oleifera plant from the Pakistan Forest Institute, Khyber Pakhtunkhwa, Pakistan for the isolation of beneficial endophytes. The strains isolated from the leaves of M. oleifera were coded with MOL and tested for antimicrobial, antifungal, germicidal, phytotoxic, insecticidal, cytotoxic, and anti-inflammatory activities. The isolates, MOL1, MOL16, MOL19, and MOL21, possessed antibacterial activity against Staphylococcus aureus, whereas MOL7 inhibited 55% of the growth of Escherichia coli. MOL3 inhibited the growth of E. coli, S. aureus, and Pseudomonas aeruginosa. The strains, MOL1 and MOL7, showed antifungal activity against Candida albicans and Saccharomyces cerevisiae, while the strains, MOL11 and MOL17, showed activity against Verticillium chlamydosporium. The isolates, MOL3, MOL7, MOL9, MOL15, MOL17, MOL18, and MOL19, inhibited the growth of Lemna minor (duckweed) at 100 µg/ml. MOL2 exhibited strong activity in the brine shrimp assay, while MOL1, MOL2, MOL5, MOL6, MOL12, MOL17, MOL19, and MOL20 showed insecticidal, and MOL3 demonstrated larvicidal and antileishmanial activity. The isolated potent endophytes were identified as Aspergillus, Penicillium, Fusarium, Tricoderma, Rhizoctonia, Mucor, Alternaria, Pestalotiopsis, Acremonium, and Cladosporium through morphological and microscopic characteristics of the colonies.


Assuntos
Anti-Infecciosos , Moringa oleifera , Antifúngicos/farmacologia , Staphylococcus aureus , Escherichia coli , Testes de Sensibilidade Microbiana , Fungos , Anti-Infecciosos/farmacologia , Folhas de Planta , Endófitos
12.
Microsc Res Tech ; 85(2): 755-766, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34570406

RESUMO

Rusts comprises the largest natural group of plant pathogens including approximately 8% of all described Fungi. Rust fungi are extremely plant pathogens responsible for great losses to agriculture productivity. Rust species belong to several genera among which more than half are Puccinia species. In Pakistan, rust causes severe damage to agriculture crops. Current study was carried out to identify and characterize different rust species common in the research area through microscopy and Scanning electron microscopy (SEM) in Khyber Pakhtunkhwa, Pakistan. Morpho-anatomical investigation of each collected rust species was carried out using different standard protocols. The dimensions of spores were measured and snapped under a stereomicroscope. SEM was used to examine the shape, size, and ornamentation of the spores of each rust fungus. Results revealed documentation of seven rust fungi, that is, Melampsora euphorbiae, Phragmidium barclayi, Puccinia nepalensis, P. exhausta, P. menthae, Uromyces capitatus, and Uromyces decorates belong to four different genera, were recorded. SEM revealed that spermogonia and Aecia were missing in most of the rust fungus studied. Uredinia was found in a scattered, irregular, lengthy, and epidermis-enclosed form. Urediniospores were found to be ovulating, elongated, echinulate, globose to sub-globose, ellipsoid to ovoid, and globose to sub-globose. Telia was found as sub-epidermal, amphigenous, dispersed, minute, and spherical cells. Teliospores ranged in form from cylindrical to oblong. The germ pores were detected in both apical (top cell) and basal (bottom cell) idiosyncratic and pedicel-attached cells. The techniques used in the current investigation will aid mycologists in rust identification and microscopic characterization.


Assuntos
Fungos , Doenças das Plantas , Microscopia Eletrônica de Varredura , Paquistão
13.
Microorganisms ; 10(7)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35889005

RESUMO

Among abiotic stresses, heat stress is described as one of the major limiting factors of crop growth worldwide, as high temperatures elicit a series of physiological, molecular, and biochemical cascade events that ultimately result in reduced crop yield. There is growing interest among researchers in the use of beneficial microorganisms. Intricate and highly complex interactions between plants and microbes result in the alleviation of heat stress. Plant-microbe interactions are mediated by the production of phytohormones, siderophores, gene expression, osmolytes, and volatile compounds in plants. Their interaction improves antioxidant activity and accumulation of compatible osmolytes such as proline, glycine betaine, soluble sugar, and trehalose, and enriches the nutrient status of stressed plants. Therefore, this review aims to discuss the heat response of plants and to understand the mechanisms of microbe-mediated stress alleviation on a physio-molecular basis. This review indicates that microbes have a great potential to enhance the protection of plants from heat stress and enhance plant growth and yield. Owing to the metabolic diversity of microorganisms, they can be useful in mitigating heat stress in crop plants. In this regard, microorganisms do not present new threats to ecological systems. Overall, it is expected that continued research on microbe-mediated heat stress tolerance in plants will enable this technology to be used as an ecofriendly tool for sustainable agronomy.

14.
PLoS One ; 17(10): e0273908, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36240136

RESUMO

Endophytic fungi from the Chilli were used to help okra plants exposed to cadmium (Cd) or chromium (Cr) stress. Initially, the strain Ch06 produced higher amounts of indole acetic acid (IAA) (230.5 µg/mL), sugar (130.7 µg/mL), proteins (128.2 µg/mL), phenolics (525.6 µg/mL) and flavonoids (98.4 µg/mL) in Czapek broth supplemented with Cd or Cr. The production of IAA and other metabolites in such a higher concentration suggested that Ch06 might improve plant growth under heavy metal stress. For this reason, an experiment was designed, in which biomass of Ch06 (at 2g/100g of sand) were applied to the okra plants exposed to Cd or Cr stress (at 100 or 500 µg/g). The results exhibited that Ch06 improved the total chlorophyll (36.4±0.2 SPAD), shoot length (22.6±0.2 cm), root length (9.1±0.6 cm), fresh weight (5±0.6 g), dry weight (1.25±0.01 g), sugars (151.6 µg/g), proteins (114.8 µg/g), proline (6.7 µg/g), flavonoids (37.9 µg/g), phenolics (70.7 µg/g), IAA (106.7 µg/g), catalase (0.75 enzyme units/g tissue) and ascorbic acid oxidaze (2.2 enzyme units/g tissue) of the associated okra plants. Similar observations have been recorded in Ch06 associated okra plants under Cd and Cr stress. Also, Ch06 association reduced translocation of Cd (35% and 45%) and Cr (47% and 53%) to the upper parts of the okra plants and thus reduced their toxicity. The internal transcribed spacer (ITS) region amplification of 18S rDNA (ribosomal deoxyribo nucleic acid) exhibited that the potent strain Ch06 was Aspergillus violaceofuscus. The results implied that A. violaceofuscus has the ability to promote host species growth exposed to Cd and Cr. Moreover, it helped the host plants to recover in Cd and Cr polluted soils, hence can be used as biofertilizer.


Assuntos
Abelmoschus , Metais Pesados , Ácidos Nucleicos , Poluentes do Solo , Abelmoschus/metabolismo , Ácido Ascórbico , Aspergillus , Biodegradação Ambiental , Cádmio/metabolismo , Cádmio/toxicidade , Catalase , Clorofila , Cromo/toxicidade , DNA Ribossômico , Flavonoides , Prolina/metabolismo , Areia , Poluentes do Solo/análise , Açúcares
15.
Front Plant Sci ; 13: 967672, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618664

RESUMO

Introduction: Drought has become more prevalent due to dramatic climate change worldwide. Consequently, the most compatible fungal communities collaborate to boost plant development and ecophysiological responses under environmental constraints. However, little is known about the specific interactions between non-host plants and endophytic fungal symbionts that produce growth-promoting and stress-alleviating hormones during water deficits. Methods: The current research was rationalized and aimed at exploring the influence of the newly isolated, drought-resistant, ACC deaminase enzyme-producing endophytic fungi Trichoderma gamsii (TP), Fusarium proliferatum (TR), and its consortium (TP+TR) from a xerophytic plant Carthamus oxycantha L. on Moringa oleifera L. grown under water deficit induced by PEG-8000 (8% osmoticum solution). Results: The current findings revealed that the co-inoculation promoted a significant enhancement in growth traits such as dry weight (217%), fresh weight (123%), root length (65%), shoot length (53%), carotenoids (87%), and chlorophyll content (76%) in comparison to control plants under water deficit. Total soluble sugars (0.56%), proteins (132%), lipids (43%), flavonoids (52%), phenols (34%), proline (55%), GA3 (86%), IAA (35%), AsA (170%), SA (87%), were also induced, while H2O2 (-45%), ABA (-60%) and ACC level (-77%) was decreased by co-inoculation of TP and TR in M. oleifera plants, compared with the non-inoculated plants under water deficit. The co-inoculum (TP+TR) also induced the antioxidant potential and enzyme activities POX (325%), CAT activity (166%), and AsA (21%), along with a lesser decrease (-2%) in water potential in M. oleifera plants with co-inoculation under water deficit compared with non-inoculated control. The molecular analysis for gene expression unraveled the reduced expression of ethylene biosynthesis and signaling-related genes up to an optimal level, with an induction of antioxidant enzymatic genes by endophytic co-inoculation in M. oleifera plants under water deficit, suggesting their role in drought stress tolerance as an essential regulatory function. Conclusion: The finding may alert scientists to consider the impacts of optimal reduction of ethylene and induction of antioxidant potential on drought stress tolerance in M. oleifera. Hence, the present study supports the use of compatible endophytic fungi to build a bipartite mutualistic symbiosis in M. oleifera non-host plants to mitigate the negative impacts of water scarcity in arid regions throughout the world.

16.
Mycologia ; 102(5): 989-95, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943499

RESUMO

Gibberellin (GA) production by soil fungi has received little attention, although substantial work has been carried out on other aspects of plant growth promoting fungi (PGPF). In our studies we investigated GA production and growth-promoting capacity of a novel fungal strain isolated from the roots of soil-grown cucumber. Pure cultures of 19 endophytic fungi were tested for shoot length promotion of Waito-C rice to identify the GA production capacity of these fungal isolates. Isolate MH-6 significantly increased shoot length (12.9 cm) of Waito-C, in comparison to control treatments. Bioassay with culture filtrate (CF) of MH-6 also significantly promoted growth attributes of cucumber plants. Analysis of MH-6 CF showed the presence of physiologically active (GA1, 1.97 ng/mL; GA3, 5.18 ng/mL; GA4, 13.35 ng/mL and GA7, 2.4 ng/ mL) in conjunction with physiologically inactive (GA9 [0.69 ng/mL], GA12 [0.24 ng/mL], GA15 [0.68 ng/ mL, GA19 [1.94 ng/mL and GA20 [0.78 ng/mL]) gibberellins. The CF of MH-6 produced greater amounts of GA3, GA4, GA7 and GA19 than wild type Fusarium fujikuroi, a fungus known for high production of GA. The fungal isolate MH-6 was identified as a new strain of Cladosporium sp. on the basis of sequence homology (99%) and phylogenetic analysis of 18S rDNA sequence.


Assuntos
Cladosporium/genética , Cucumis sativus/microbiologia , Giberelinas/biossíntese , Desenvolvimento Vegetal , Cladosporium/classificação , Cladosporium/crescimento & desenvolvimento , Cladosporium/isolamento & purificação , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Giberelinas/genética , Crescimento/fisiologia , Filogenia , Raízes de Plantas/microbiologia , RNA Fúngico/genética , RNA Ribossômico 16S/genética
17.
J Microbiol Biotechnol ; 20(1): 202-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20134253

RESUMO

Plant growth promoting fungi (PGPF) are well known for the production of useful secondary metabolites. However, limited information's are available on gibberellin (GA) production capacity of PGPF of endophytic origin. In current study, 15 fungal endophytes were isolated from the roots of Crown daisy, and then screened on Waito-c rice, in order to identify plant growth promoting fungi. The fungal isolate MH7 significantly increased shoot length (12.1 cm) of Waito-c in comparison to control treatment (7.9 cm). In a separate experiment, culture filtrate (CF) of MH7 significantly promoted growth attributes of Crown daisy. The MH7 CF was analyzed for gibberellins and it contained all physiologically active gibberellins (GA1, 1.37 ng/ml; GA3, 5.88 ng/ml; GA4, 8.62 ng/ml and GA7, 2.05 ng/ml) in conjunction with physiologically inactive GA9 (0.83 ng/ml), GA12 (0.44 ng/ml), GA15 (0.74 ng/ml), GA19 (1.16 ng/ml) and GA20 (0.98 ng/ml). The CF of MH7 produced higher amounts of GA3, GA4, GA7, GA9 and GA12 than wild type Fusarium fujikuroi, which was used as control for GA production. The fungal isolate MH7 was later identified as a new strain of Penicillium on the basis of morphological characteristics and phylogenetic analysis of 18S rDNA sequence.


Assuntos
Chrysanthemum/microbiologia , Giberelinas/biossíntese , Oryza/crescimento & desenvolvimento , Penicillium/isolamento & purificação , Penicillium/metabolismo , Reguladores de Crescimento de Plantas/biossíntese , Oryza/microbiologia , Penicillium/classificação , Penicillium/genética , Filogenia , Raízes de Plantas/microbiologia
18.
Biotechnol Lett ; 31(2): 283-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18931975

RESUMO

Plant growth-promoting endophytic fungi with gibberellin-producing ability were isolated from the roots of Carex kobomugi Ohwi, a common sand-dune plant, and bioassayed for plant growth-promotion. A new strain, Arthrinium phaeospermum KACC43901, promoted growth of waito-c rice and Atriplex gemelinii. Analysis of its culture filtrate showed the presence of bioactive GA(1) (0.5 ng/ml), GA(3) (8.8 ng/ml), GA(4) (4.7 ng/ml) and GA(7) (2.2 ng/ml) along with physiologically inactive GA(5) (0.4 ng/ml), GA(9) (0.6 ng/ml), GA(12) (0.4 ng/ml), GA(15) (0.4 ng/ml), GA(19) (0.9 ng/ml) and GA(24) (1.8 ng/ml). The fungal isolate was identified through sequence homology and phylogenetic analysis of 18S rDNA (internal transcribed region).


Assuntos
Ascomicetos/fisiologia , Atriplex/crescimento & desenvolvimento , Atriplex/microbiologia , Carex (Planta)/microbiologia , Giberelinas/biossíntese , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Raízes de Plantas/microbiologia , Especificidade da Espécie
19.
J Microbiol Biotechnol ; 19(6): 560-5, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19597313

RESUMO

We isolated nine endophytic fungi from the roots of saltstressed soybean cultivar Daewonkong and screened them for growth-promoting secondary metabolites. Of all fungal isolates, P-4-3 induced maximum growth promotion of waito-c rice and soybean. Analysis of the culture filtrate of P-4-3 showed the presence of physiologically active gibberellins GA1, GA3, GA4, and GA7, along with physiologically inactive GA15 and GA24. The plant growth promotion and gibberellinproducing capacity of P-4-3 was much higher than wildtype Gibberella fujikuroi, which was taken as the control during the present study. The fungal isolate P-4-3 was identified as a new strain of Scolecobasidium tshawytschae through the morphological characteristics and phylogenetic analysis of 18S rDNA sequence. Gibberellins production and plant growth promoting ability of genus Scolecobasidium was reported for the first time in the present study.


Assuntos
Ascomicetos/metabolismo , Giberelinas/biossíntese , Glycine max , Ascomicetos/classificação , Ascomicetos/genética , DNA Fúngico/análise , DNA Fúngico/genética , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Filogenia , RNA Ribossômico 18S/análise , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Glycine max/crescimento & desenvolvimento , Glycine max/microbiologia , Especificidade da Espécie , Simbiose
20.
J Microbiol Biotechnol ; 19(10): 1244-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19884787

RESUMO

Endophytic fungi are known for the production of valuable metabolites, but information on the gibberellin production capacity of this group is limited. We isolated 9 endophytic fungi from the roots of salt-stressed soybean plants and screened them on waito-c rice, in order to identify plant growth promoting fungal strains. The fungal isolate TK- 2-4 gave maximum plant length (20.35 cm) promotion in comparison with wild-type Gibberella fujikuroi (19.5 cm). In a separate experiment, bioassay of TK-2-4 promoted plant length and biomass of soybean cultivar Taegwangkong. The TK-2-4 culture filtrate was analyzed for the presence of gibberellins, and it was found that all physiologically active gibberellins, especially GA(4) and GA(7), were present in higher amounts (GA(1), 0.11 ng/ml; GA(3), 2.91 ng/ml; GA(4), 3.21 ng/ml; and GA(7), 1.4 ng/ml) in conjunction with physiologically inactive GA(9) (0.05 ng/ml), GA(12) (0.23 ng/ ml), GA(15) (0.42 ng/ml), GA(19) (0.53 ng/ml), and GA(20) (0.06 ng/ml). The fungal isolate TK-2-4 was later identified as a new strain of Phoma herbarum, through the phylogenetic analysis of 28S rDNA sequence.


Assuntos
Ascomicetos/isolamento & purificação , Giberelinas/metabolismo , Glycine max/microbiologia , Oryza/crescimento & desenvolvimento , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/metabolismo , Biomassa , Dados de Sequência Molecular , Oryza/microbiologia , Filogenia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Glycine max/crescimento & desenvolvimento
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