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1.
The method proposed in this study was used to isolate fungi grown under anaerobic conditions and to reveal distinctions in their abundance and species composition in different habitats. The ability of micromycetes of different taxa to grow under anaerobic conditions and ensure alcohol fermentation was determined for a representative sample (344 strains belonging to more than 60 species). The group of fungi growing under anaerobic conditions included species with high, moderate, and low fermentation activity. The ability for anaerobic growth and fermentation depended on the taxonomic affiliation of fungi. In some cases, the expression of these characteristics depended on the habitat from which the strain was isolated. The maximum level of ethanol accumulation in culture liquid (1.2–4.7%) was detected for Absidia spinosa, Aspergillus sp. of group flavus, Aspergillus terreus, Acremonium sp., Mucor circinelloides, Mucor sp., Fusarium oxysporum, F. solani, F. sambucinum, Rhizopus arrhizus var. arrhizus, Trichoderma atroviride, and Trichoderma sp.  相似文献   

2.
用组织分离法从采集于广东鼎湖山的腐殖质中分离得到一株枝顶孢属真菌(Acremonium sp. SC0105),其固体发酵物的乙醇提取物对金黄色葡萄球菌(Staphylococcus aureus)有较强的抑制作用。经多种柱层析,从固体发酵物中分离得到5个化合物。通过光谱分析,分别鉴定为姜糖脂B (1)、姜糖脂C (2)、D-甘露醇(3)、酒渣碱(4)、枝顶孢素F(5)。其中酒渣碱是首次从枝顶孢属真菌中分离得到。  相似文献   

3.
The aim of this work was to select endophytic fungi from mangrove plants that produced antimicrobial substances. Minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) or minimal fungicidal concentrations (MFC) of crude extracts from 150 isolates were determined against potential human pathogens by a colorimetric microdilution method. Ninety-two isolates (61.3%) produced inhibitory compounds. Most of the extracts (28–32%) inhibited Staphylococcus aureus (MIC/MBC 4–200/64–200 μg ml−1). Only two extracts inhibited Pseudomonas aeruginosa (MIC/MBC 200/>200 μg ml−1). 25.5 and 11.7% inhibited Microsporum gypseum and Cryptococcus neoformans (MIC/MFC 4–200/8–200 μg ml−1 and 8–200/8–200 μg ml−1, respectively), while 7.5% were active against Candida albicans (MIC/MFC 32–200/32–200 μg ml−1). None of the extracts inhibited Escherichia coli. The most active fungal extracts were from six genera, Acremonium, Diaporthe, Hypoxylon, Pestalotiopsis, Phomopsis, and Xylaria as identified using morphological and molecular methods. Phomopsis sp. MA194 (GU592007, GU592018) isolated from Rhizophora apiculata showed the broadest antimicrobial spectrum with low MIC values of 8–32 μg ml−1against Gram-positive bacteria, yeasts and M. gypseum. It was concluded that endophytic fungi from mangrove plants are diverse, many produce compounds with antimicrobial activity and could be suitable sources of new antimicrobial natural products.  相似文献   

4.
The production of cellulolytic enzymes by Aspergillus niger on lignocellulosic substrates groundnut fodder, wheat bran, rice bran and sawdust in solid state fermentation in a laboratory scale was compared. Czapek Dox liquid broth amended with cellulose (0.5%) was used to moisten lignocellulosic solid supports for cultivation of Aspergillus niger. The production of filter paperase, carboxymethyl cellulase and -glucosidase were monitored at daily intervals for 5 days. The peak production of the enzymes occurred within 3 days of incubation. Among solid supports used in the study, wheat bran was the best solid matrix followed by groundnut fodder in production of cellulolytic enzymes in solid state fermentation. Groundnut fodder supported significant production of FPase (2.09 FPU/g), CMCase (1.36 U/g) and -glucosidase activity (0.0117 U/g) in solid state fermentation. Considerable secretion of protein (5.10 mg/g) on groundnut fodder at peak time interval 1st day of incubation was recorded.  相似文献   

5.
India is the highest producer of Cicer arietinum, however the crop is susceptible to plant fungal diseases i.e. Sclerotinia sclerotiorum, Botrytis cinerea, Fusarium oxysporum and Rhizoctonia solani. For a sustainable alternative, anti-plant pathogenic efficacy of fungal endophytes were investigated. Endophytic fungi of Mentha piperita were investigated for biodiversity, biocontrol potential towards these phytopathogens and their metabolite profiling. Sixty three fungal isolates were recovered from peppermints sampled in different seasons from distinct regions of India. Endophytic fungi were identified by ITS-rDNA sequence process. PCA divulged seasonal variability with exclusive presence of Colletotrichum sp., D. phaseolorum, Alternaria sp., Hypocrea sp. and R. oryzae in second sampling season. Shannon diversity index (H′) was found to be highest in leaf (1.253) from Mukteshwar. Acremonium sp. (MPM-2.1) extract exhibited anti-plant pathogenic activity with < 1 mg/ml IC50 value towards phytopathogens. GC-MS chromatography of potent biocontrol fungus Acremonium sp. (MPHSS-2.1) confirmed presence of antifungal compounds 1-heptacosanol and 1-nonadecane.  相似文献   

6.
Two fungal pathogens of the mantis shrimp (Oratosquilla oratoria) in Yamaguchi and Aichi Prefectures, Japan are described as the new species Plectosporium oratosquillae and Acremonium sp. (a member of the Emericellopsis marine clade). Both fungi infect the gills of the mantis shrimp, which become brown or black due to melanization. The former species is characterized by its slow growth on artificial seawater yeast extract peptone glucose (PYGS) agar, pale yellow to pale orange or grayish yellow colonies, short cylindrical solitary phialides with a wavy tip, and one-celled ellipsoidal conidia. Although lacking the two-celled conidia demonstrated by the type species Plectosporium tabacinum, the taxonomic placement of the new species was confirmed by DNA sequence analysis of the internal transcribed spacer (ITS) region of ribosomal DNA (ITS1, 5.8S rDNA and ITS2). Acremonium sp., the other causal pathogen, differs from P. oratosquillae by its fast growth on PYGS agar, pale orange to salmon-colored colonies, long, slender conidiophores consisting of solitary phialides with tips lacking an undulate outline, and typically cylindrical conidia. Analysis of ITS and β-tubulin gene sequences placed this fungus within the phylogenetically distinct Emericellopsis (anam. Acremonium) marine clade. Various physiological characteristics of both pathogens were also investigated. This is the first report of a fungal infection found on the mantis shrimp in Japan.  相似文献   

7.
A new antagonistic Burkholderia strain, designated MP-1 and producing antifungal activities against various filamentous plant pathogenic fungi, was isolated from the rhizoshere in the Naju area. Cultural characteristic studies strongly suggested that this strain belongs to the genus Burkholderia. The nucleotide sequence of the 16S rRNA gene (1491 pb) of strain MP-1 exhibited close similarity (99% to 100%) with other Burkholderia 16S rRNA genes. Extraction of fermentation broth of Burkholderia sp. MP-1 and various separations and purification steps led to isolation of four pure active molecules. The chemical structure of these four compounds—named phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid, and 4-hydroxyphenylacetate methyl ester—was established on the basis on their gas chromatography–electron impact–mass spectrometry (GC-EI-MS) and trimethylsilation GC-EI-MS data. The four isolated compounds inhibited filamentous fungal growth on potato dextrose agar medium supplemented with 100 mg/L of phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid and 4-hydroxyphenylacetate methyl ester individually.  相似文献   

8.
A total of 250 endophytic fungal isolates, representing 30 morphotaxa, were isolated and characterised, they were collected from the different living symptomless parts of date palm trees of orchards of six Egyptian governorates. Colonisation was greater in samples from the midrib than in those from laminar tissue and slightly greater at the tip of the lamina compared with the base of the leaf. Acremonium spp. were frequently isolated as date palm root endophytes. Acremonium isolates were screened in Petri dishes to select the highest antagonistic one against an Algerian isolate of Fusarium oxysporum f.sp. albedinis. Two-week-old axenically reared date palm seedlings grown in Petri dishes were directly injected with spore suspension (1.5?×?107 spores/ml) of a pure culture of the virulent antagonistic isolate of Acremonium sp. One week after endophytic colonisation, date palm seedlings were then challenged with the pathogen, Fusarium albedinis. The challenged seedlings exhibited a significant reduction in wilt symptom percentage (by 87.0%), while the seedlings exposed to Fusarial toxin without pathogen exhibited the wilt disease symptoms. This indicates that the endophyte ably depresses any toxic action of F. albedinis. The endophytic fungus was recovered from sites distant from the point of inoculation after six?months from the application, indicating that the Acremonium sp. has the potential to move throughout the tissue plant, even the end time of trial. The Acremonium mode of action, as a biocontrol agent, was discussed.  相似文献   

9.
Summary A saprophytic filamentous fungus, Monilia sp., isolated from bagasse compost was found to utilize many polysaccharides (including cellulose) and to produce cellulases and hemicellulases. Monilla sp. also fermented glucose, xylose and cellulosic materials to ethanol. Over 60% of the solid cellulose substrate added to Monilia sp. cultures was converted to ethanol as the major fermentation product. These results indicate that Monilia sp. is a potential organism for the direct conversion of cellulosic biomass to ethanol.  相似文献   

10.
We investigated the ectomycorrhizal (ECM) fungal colonization status of Pinus thunbergii mature trees and regenerating seedlings varying in age in coastal pine forests on the east coast of Korea. We established one 20 × 20-m plot at each of two study sites at P. thunbergii coastal forests in Samcheok. Fifty soil blocks (5 × 5 × 15 cm) were sampled at regular intervals, and ten P. thunbergii seedlings of age 0, 1–3, 3–5, and 5–10 years were sampled in each study plot. In total of 27 ECM fungal taxa, Cenococcum geophilum was dominant, followed by Russula sp., Sebacina sp., and unidentified Cortinuris sp. in mature trees. In 0-year-old seedlings, some fungal species such as Sebacina sp., C. geophilum, and unidentified Cortinarius sp. were dominant whereas only C. geophilum was dominant after 1 year, and there were no apparent succession patterns in ECM fungal compositions beyond a host age of 1 year. Most ECM fungal taxa that had colonized seedlings of each age class were also observed in roots of mature trees in each site. These taxa accounted for 86.7–100% and 96.4–98.4% of ECM abundance in seedlings and mature trees, respectively. The results indicate that the species composition of ECM fungal taxa colonizing seedlings of different age in forests is similar to that of surrounding mature trees. Our results also showed that C. geophilum is a common and dominant ECM fungus in P. thunbergii coastal forests and might play a significant role in their regeneration.  相似文献   

11.
 Root pathogens cause considerable loss of tree seedlings in nurseries and are generally difficult to control using conventional methods. Inoculation with ectomycorrhizal fungi may provide some suppression of pathogens. Bacteria (so-called mycorrhization helper bacteria) have been isolated that stimulate mycorrhiza formation on seedling roots and enhance seedling growth; however, their role in pathogen inhibition has not been explored. Four strains of helper bacteria were inoculated together with the ectomycorrhizal fungal species Laccaria bicolor, L. proxima and Suillus granulatus on culture plates to determine inhibition of the pathogens Fusarium oxysporum and Cylindrocarpon sp. Buffered medium was used to rule out acidification of the medium as a mechanism of inhibition. None of the ectomycorrhizal fungal species alone inhibited the growth of Fusarium but all showed slight inhibition of Cylindrocarpon growth. Helper bacterium strain MB3 (Bacillus subtilis) was effective in inhibiting both pathogens and, when inoculated with either L. proxima or S. granulatus, inhibition of Fusarium growth was enhanced over MB3 alone. With Cylindrocarpon, however, only S. granulatus inoculated along with MB3 showed enhanced inhibition over MB3 alone. The other three bacterial strains had little effect on the growth of Fusarium or Cylindrocarpon. More research is necessary to determine if these inhibitory effects are reproducible in situ. Accepted: 23 October 1996  相似文献   

12.
Aims: To characterize and identify a novel Huperzine A (HupA)‐producing fungal strain Slf14 isolated from Huperzia serrata (Thunb. ex Murray) Trev. in China. Methods and Results: The isolation, identification and characterization of a novel endophytic fungus producing HupA specifically and consistently from the leaves of H. serrata were investigated. The fungus was identified as Shiraia sp. Slf14 by molecular and morphological methods. The HupA produced by this endophytic fungus was shown to be identical to authentic HupA analysed by thin layer chromatographic, High‐performance liquid chromatography (HPLC), LC‐MS, 1H NMR and acetylcholinesterase (AChE) inhibition activity in vitro. The amount of HupA produced by Shiraia sp. Slf14 was quantified to be 327·8 μg l?1 by HPLC, which was far higher than that of the reported endophytic fungi, Acremonium sp., Blastomyces sp. and Botrytis sp. Conclusions: The production of HupA by endophyte Shiraia sp. Slf14 is an enigmatic observation. It would be interesting to further study the HupA production and regulation by the cultured endophyte in H. serrata and in axenic cultures. Significance and Impact of the Study: Although the current accumulation of HupA by the endophyte is not very high, it could provide a promising alterative approach for large‐scale production of HupA. However, further strain improvement and the fermentation process optimization are required to result in the consistent and dependable production.  相似文献   

13.
【目的】探讨碳源和甲烷菌对厌氧真菌碳代谢的影响。【方法】利用体外批次厌氧发酵法,比较厌氧真菌纯培养(Orpinomyces sp.和Neocallimastix sp.)及其与甲烷菌共培养(F1:Orpinomyces sp.+Methanobrevibacter sp.和N3:Neocallimastix sp.+Methanobrevibacter sp.)发酵不同类型碳水化合物代谢产物的差异。【结果】对厌氧真菌和甲烷菌共培养F1和N3的研究显示,F1发酵木薯粉[(26.44±0.22)mmol/L]的乳酸产量是发酵玉米芯[(1.31±0.04)mmol/L]的20.18倍,是N3发酵木薯粉[(1.59±0.03)mmol/L]的16.63倍,玉米芯[(0.79±0.08)mmol/L]的33.47倍。当F1和N3中的厌氧真菌纯培养时,各组乳酸产量均1.90 mmol/L。对F1进一步研究,结果显示发酵体系中木薯粉添加量在0.8%–2.0%之间时,乳酸产量随木薯粉添加量增加而增加。当含量在1.0%–2.4%之间时,随木薯粉添加量增加,甲烷和乙酸产量逐渐降低。比较F1发酵大米粉、木薯粉、玉米粉、小麦粉和土豆粉的发酵结果,发现乳酸产量与底物中支链淀粉的含量成正相关(R2=0.9554)。当F1发酵葡萄糖和麦芽糖时,乳酸产量5.00 mmol/L。当以麦芽糊精为底物时,乳酸产量高达(28.00±0.95)mmol/L。【结论】本文首次报道碳源和甲烷菌能够增强厌氧真菌的乳酸代谢途径并且这种增强存在种属特异性。  相似文献   

14.
The biochemical kinetic of direct fermentation for lactic acid production by fungal species of Rhizopus arrhizus 3,6017 and Rhizopus oryzae 2,062 was studied with respect to growth pH, temperature and substrate. The direct fermentation was characterized by starch hydrolysis, accumulation of reducing sugar, and production of lactic acid and fungal biomass. Starch hydrolysis, reducing sugar accumulation, biomass formation and lactic acid production were affected with the variations in pH, temperature, and starch source and concentration. A growth condition with starch concentration approximately 20 g/l at pH 6.0 and 30°C was favourable for both starch saccharification and lactic acid fermentation, resulting in lactic acid yield of 0.87–0.97 g/g starch associated with 1.5–2.0 g/l fungal biomass produced in 36 h fermentation. R. arrhizus 3,6017 had a higher capacity to produce lactic acid, while R. oryzae 2,062 produced more fungal biomass under similar conditions.  相似文献   

15.
Endophytic fungi can be beneficial to plant growth. However, the molecular mechanisms underlying colonization of Acremonium spp. remain unclear.In this study, a novel endophytic Acremonium strain was isolated from the buds of Panax notoginseng and named Acremonium sp. D212. The Acremonium sp. D212 could colonize the roots of P. notoginseng,enhance the resistance of P. notoginseng to root rot disease, and promote root growth and saponin biosynthesis in P. notoginseng. Acremonium sp. D212 could secrete indole-3-acetic acid(IAA) and jasmonic acid(JA), and inoculation with the fungus increased the endogenous levels of IAA and JA in P. notoginseng. Colonization of the Acremonium sp. D212 in the roots of the rice line Nipponbare was dependent on the concentration of methyl jasmonate(Me JA)(2–15 μmol/L) and 1-naphthalenacetic acid(NAA)(10–20 μmol/L). Moreover, the roots of the JA signaling-defective coi1-18 mutant were colonized by Acremonium sp. D212 to a lesser degree than those of the wild-type Nipponbare and mi R393 boverexpressing lines, and the colonization was rescued by Me JA but not by NAA. It suggests that the cross-talk between JA signaling and the auxin biosynthetic pathway plays a crucial role in the colonization of Acremonium sp. D212 in host plants.  相似文献   

16.
Unexpected pathogens from the environment represent considerable risk for humans with impaired health. We examined the occurrence of itraconazole tolerant micromycetes in soil and in maize products. Five concentrations of itraconazole (2.5–12.5 μg/mL) selected according to known treatment schedules for human patients were incorporated into Sabouraud agar with chloramphenicol and Rose Bengal and diluted samples were inoculated onto the agar surface. After 7-d growth at 22°C colonies ofAlternaria sp.,Aspergillus clavatus. A. glaucus group,A. flavus. A, fumigatus, A. niger group,A. ochraceus group,A. ochraceus, Chœtomium sp.,Cladosporium cladosporioides. Cylindrocarpon sp.Doratomyces sp.,Fusarium sp.,F. moniliforme. F. oxysporum. F. solani, F. subglutinans. Marianaea elegans, Mortierella sp.,Mucor sp.,Myrothecium sp.,Penicillium sp.,Rhizopus sp.,Scopulariopsis brevicaulis. Sepedonium sp.,Stachybotrys chartarum. Stemphylium sp.,Torula humicola andTrichoderma viride were isolated.  相似文献   

17.
Culture media and fermentation conditions for cultivation of an endophytic fungus Phomopsis sp. Hant25 were investigated in order to improve the yield of mycoepoxydiene, a novel fungal metabolite having potent cytotoxic activity against many cancer cell lines. Mycoepoxydiene accumulated in the culture broth during the stationary phase of fungal growth. Modified M1D medium was superior to malt Czapek, and Czapek yeast autolysate broths in supporting mycoepoxydiene production. Pellet growth was the morphological form that favored biosynthesis of mycoepoxydiene. This could be achieved by incubating the culture statically for 6 days before shaking at 120 rpm. Incorporation of a cellulose paper disc into the culture flask promoted fungal growth at the liquid surface, which accelerated mycoepoxydiene production and maximized the final yield to a level of 354 mg l−1, though fungal attachment to the solid support was not required. Since the peak concentration of mycoepoxydiene in the culture broth was followed by a steeply declining phase, the harvest time had to be precisely determined for maximum product yield. Understanding the factor(s) involved in rapid degradation of mycoepoxydiene could lead to improved final yields.  相似文献   

18.
The biological delignification of lignocellulosic feedstocks, Prosopis juliflora and Lantana camara was carried out with Pycnoporus cinnabarinus, a white rot fungus, at different scales under solid-state fermentation (SSF) and the fungal treated substrates were evaluated for their acid and enzymatic saccharification. The fungal fermentation at 10.0 g substrate level optimally delignified the P. juliflora by 11.89% and L. camara by 8.36%, and enriched their holocellulose content by 3.32 and 4.87%, respectively, after 15 days. The fungal delignification when scaled up from 10.0 g to 75.0, 200.0 and 500.0 g substrate level, the fungus degraded about 7.69–10.08% lignin in P. juliflora and 6.89–7.31% in L. camara, and eventually enhanced the holocellulose content by 2.90–3.97 and 4.25–4.61%, respectively. Furthermore, when the fungal fermented L. camara and P. juliflora was hydrolysed with dilute sulphuric acid, the sugar release was increased by 21.4-42.4% and the phenolics content in hydrolysate was decreased by 18.46 and 19.88%, as compared to the unfermented substrate acid hydrolysis, respectively. The reduction of phenolics in acid hydrolysates of fungal treated substrates decreased the amount of detoxifying material (activated charcoal) by 25.0–33.0% as compared to the amount required to reduce almost the same level of phenolics from unfermented substrate hydrolysates. Moreover, an increment of 21.1–25.1% sugar release was obtained when fungal treated substrates were enzymatically hydrolysed as compared to the hydrolysis of unfermented substrates. This study clearly shows that fungal delignification holds potential in utilizing plant residues for the production of sugars and biofuels.  相似文献   

19.
The properties of intracellular β-glucosidases produced from two yeast isolates identified as Hanseniaspora sp. BC9 and Pichia anomala MDD24 were characterized. β-Glucosidase from Hanseniaspora sp. BC9 was not inhibited by both 20% w/v fructose and 20% w/v sucrose and was slightly inhibited by glucose (> 40% relative β-glucosidase activity with 10% w/v glucose). β-Glucosidase from P. anomala MDD24 was inhibited by glucose, fructose and sucrose. In the presence of 4–12% v/v ethanol, β-glucosidase from P. anomala MDD24 was stimulated in range 110–130% relative activity whereas β-glucosidase from Hanseniaspora sp. BC9 was substantially inhibited in the presence of ethanol. Finally, juice and wine of the Muscat-type grape variety, Traminette, were selected to determine sugar-bound volatile aroma release, particularly terpenes, by the activity of those β-glucosidases. The results showed that high concentration of free aroma compounds were detected from Traminette juice treated with β-glucosidase from Hanseniaspora sp. BC9 and Traminette wine treated with β-glucosidase from P. anomala MDD24. The preliminary results with proposed an application of these enzymes in commercial wine production lead to more efficient of β-glucosidase from Hanseniaspora sp. BC9 in releasing desirable aromas during an early stage of alcoholic fermentation while β-glucosidase from P. anomala MDD24 is suitable at the final stage of alcoholic fermentation.  相似文献   

20.
A custom-made stainless steel column was designed to contain various materials that would trap the hydrocarbons and hydrocarbon derivatives during the processes of fungal fermentation ultimately yielding preparative amounts of volatile organic substances (VOCs). Trapping materials tested in the column were Carbotrap materials A and B (Supelco) as well as bentonite-shale from the oil bearing areas of Eastern Montana, the former allowed for the effective and efficient trapping of VOCs from purged cultures of Hypoxylon sp. Trapping efficiencies of various materials were measured by both gravimetric as well as proton transfer reaction mass spectroscopy with the Carbotraps A and B being 99% efficient when tested with known amounts of 1,8-cineole. Trapped fungal VOCs could effectively be removed and recovered via controlled heating of the stainless steel column followed by passage of the gases through a liquid nitrogen trap at a recovery rate of ca 65–70%. This method provides for the recovery of mg quantities of compounds normally present in the gas phase that may be needed for spectroscopy, bioassays and further separation and analysis and may have wide applicability for many other biological systems involving VOCs. Other available Carbotraps could be used for other applications.  相似文献   

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