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1.
Several strains of the genusPenicillium isolated from swabs from uranium miners working environment were screened for production of known mycotoxins; and embryotoxicity of chloroform extracts from the isolates was investigated in chick embryos.Penicillium aurantiogriseum was found to produce chaetoglobosin A. ED50 of this mycotoxin for 2-, 3- and 4-day-old chick embryos was found 0.040 (0.031–0.052), 0.074 (0.051–0.107), and 0.180 (0.113–0.229) µg/embryo, respectively. The effect was purely embryolethal with no signs of teratogenicity recorded. This is the first report on the isolation of chaetoglobosin A from the genusPenicillium. 相似文献
2.
A correlation was established between species specificity and synthesis of specific secondary metabolites by the Penicillium fungi. Strains of the subgenus Aspergilloides usually synthesize metabolites of polyketide nature. Most strains of the subgenus Furcatum produce clavine ergot alkaloids and metabolites of diketopiperazine nature. The only clavine ergot alkaloids and diketopiperazine
alkaloids produced by strains of the subgenus Biverticillium are rugulovasines and rugulosuvines, respectively. Species designations of the strains of the subgenus Penicillium isolated from permafrost soil, the Mir orbital complex, and sites undergoing anthropogenic load were refined based on the marker secondary metabolites. Changes
in the taxonomic position of some strains in the genus Penicillium are suggested. 相似文献
3.
A number of Penicillium isolates were recovered in association to Rhizoctonia solani strains pathogenic on tobacco and from soil on plates pre-colonized by the pathogen itself. Their antagonism toward R. solaniAG-2-1 was evaluated in dual cultures in vitro. Inhibition of growth was evident to some extent in most pairings, while hyphal interactions referable to mycoparasitic relationships
were not observed. However, the occurrence of plasmolysis and/or vacuolisation and the induction of monilioid cells were indicative
of the release of bioactive compounds. Therefore, production of fungitoxic metabolites was tested by adding concentrated culture
filtrates of each Penicillium isolate to the growth medium of R. solani. Complete and lasting inhibition was incited by culture filtrates of some isolates belonging to P. brevicompactum, P. expansum, and P. pinophilum. Three purified compounds, respectively mycophenolic acid, patulin and 3-O-methylfunicone, which were extracted from culture filtrates, were able to inhibit R. solani
in vitro. Their production was also detected in dual cultures of the same Penicilliumstrains with R. solani prepared in sterilized soil and when the Penicilliumstrains were cultured directly on R. solani mycelium harvested from liquid cultures. The possible role of such metabolites in antagonism of the above-mentioned Penicilliumspecies against R. solani is discussed. 相似文献
4.
Leathers TD Nunnally MS Côté GL 《Journal of industrial microbiology & biotechnology》2002,29(4):177-180
Four strains identified as Penicillium spp. were isolated from soil samples based on their capacity to modify the unique polysaccharide, alternan. Spores from these
isolates germinated in medium containing alternan and reduced the apparent molecular weight of alternan as determined by high-performance
size exclusion chromatography and viscometry. However, the fungi exhibited limited growth on alternan and did not consume
the substrate. The rheological properties of the modified alternan resembled those of commercial gum arabic. Thus, treatment
of native alternan with spores from these Penicillium spp. strains constitutes a simple bioconversion method to quantitatively produce novel and potentially useful modified alternan.
Journal of Industrial Microbiology & Biotechnology (2002) 29, 177–180 doi:10.1038/sj.jim.7000272
Received 14 February 2002/ Accepted in revised form 13 May 2002 相似文献
5.
Fifty-two aerobic and facultative anaerobic and 57 anaerobic bacterial isolates were obtained from an acidogenic phase digestion system. These isolates were characterized and the similarities between the different strains were calculated using Sokal and Michener's similarity coefficient. The aerobic and facultative anaerobic strains clustered in two major groups with the strains of the first main group being gram-negative fermentative rods, representing the generaKlebsiella, Enterobacter, Escherichia andAeromonas. Isolates of the second group were gram-positive streptococci similar toStreptococcus lactis. The strict anaerobic isolates also clustered into two main groups with strains of cluster A being identified as members of the genusFusobacterium while strains in cluster B were members of the genusBacteroides. Hypothetical mean organisms were calculated for each cluster and used in further culture studies. The major products of the continuously fed acidogenic phase reactor were ethanol and acetic, propionic, and butyric acids. In batch cultures, ethanol, acetic acid, diacetyl, and 2,3-butanediol were formed by the strains as major products both under aerobic and anaerobic conditions. The ability of the aerobic and facultative anaerobic strains to be metabolically active under anaerobic conditions indicates a prominent role in acidogenic reactors. 相似文献
6.
Fortina MG Ricci G Foschino R Picozzi C Dolci P Zeppa G Cocolin L Manachini PL 《Journal of applied microbiology》2007,103(2):445-453
AIMS: To characterize Lactococcus garvieae strains of dairy origin and to determine their technological properties and safety for their possible use in starter culture preparation. METHODS AND RESULTS: Forty-seven L. garvieae isolates, recovered from two artisanal Italian cheeses were studied, in comparison with 12 fish isolates and the type strain of the species. Phenotypic typing revealed that the strains could be differentiated on the basis of their ecological niche of origin in lactose positive strains (all isolated from dairy sources) and lactose negative strains (all isolated from fish). Furthermore, the strains exhibited a high degree of physiological variability, showing the presence of 26 different biotypes. The strains possessed moderate acidifying and proteolytic activities and did not produce bacteriocins. A safety investigation revealed that all strains were sensitive to vancomycin and moderately resistant to kanamycin; some biotypes were tetracycline resistant. Production of biogenic amines or presence of genes encoding virulence determinants occurred in some isolates. CONCLUSIONS: The prevalence of L. garvieae in some artisanal Italian cheeses can be linked to the typicity of the products. Although in a few cases an antimicrobial resistance or a presence of virulence determinants may imply a potential hygienic risk, most of the strains showed positive properties for their possible adjunction in a starter culture preparation, to preserve the natural bacterial population responsible for the typical sensorial characteristics of the traditional raw milk cheeses. SIGNIFICANCE AND IMPACT OF THE STUDY: L. garvieae strains can be considered an important part of the microbial population associated with the natural fermentation of artisanal Italian cheeses. A deepened characterization of the strains may aid in understanding the functional and ecological significance of their presence in dairy products and in selecting new strains for the dairy industry. 相似文献
7.
Selection criteria for lactic acid bacteria to be used as starter cultures for various food commodities 总被引:14,自引:0,他引:14
Herbert J. Buckenhüskes 《FEMS microbiology reviews》1993,12(1-3):253-271
Abstract: Lactic acid bacteria (LAB) are the most important bacteria used in food fermentations. Apart from general demands for starter cultures from the view of safety, technological effectiveness and economics, numerous specific aspects have to be considered when selecting strains for the different food fermentations. Therefore selection criteria for LAB depend on the type and the desired characteristics of the final product, the desired metabolic activities, the characteristics of the raw materials and the applied technology. Special selection criteria for LAB for use in the fermentation of sausages and vegetables as well as for the malolactic fermentation in wine are discussed. 相似文献
8.
Sobia Mushtaq Ghazala Nasim Ibatsam Khokhar Irum Mukhtar 《Archives Of Phytopathology And Plant Protection》2013,46(8):932-937
Penicillium spp. are well known to produce a variety of beneficial metabolites for plant growth and survival, as well as they defend their hosts from attack of certain pathogens. In this study, effects of culture filtrate of different Penicillium spp. were tested on tomato seeds. On the whole, presoaking of seeds in the filtrates of the nine Penicillium isolates tested significantly increased seed germination when compared with the control seeds. Cultural extracts of P. expansum and P. bilaii were highly effective in growth promotion up to 90%. It was also observed that P. implicatum and P. oxalicum significantly enhanced the root growth in tomato seedling as compared to other species. In case of shoot length, P. verrucosum (3.38 cm), P. granulatum (2.81 cm) and P. implicatum (2.62 cm) were effective. P. implicatum was quite promising in increasing shoot and root length in tomato seedlings, while P. simplicissimum and P. citrinum were less effective on seedling growth. The plant growth-promoting ability of Penicillium strains may help in growth promotion in other plants and crops. Penicillium spp. are already known for producing various mycotoxins and enzymes. Plant growth-promoting ability of Penicillium spp. will open new aspects of research and investigations. The role of Penicillium spp. in tomato plant growth requires further exploration. 相似文献
9.
Trichoderma species are commonly used as biological control agents against phytopathogenic fungi and some strains are able to produce metabolites that enhance plant growth. In the current study we evaluated the production of potential growth-promoting metabolites, rhizosphere competence and endophytism for 101 isolates of Trichoderma from Colombia, and assessed the relationship of these factors to the enhancement of early stages of growth on bean seedlings. Twenty percent of these Trichoderma strains were able to produce soluble forms of phosphate from phosphoric rock. Only 8% of the assessed strains showed consistent ability to produce siderophores to convert ferric iron to soluble forms by chelation. Sixty percent of isolates produced indole-3-acetic acid (IAA) or auxin analogues. The production of any of these metabolites was a characteristic of specific strains, as the ability to produce these metabolites varied greatly within species. Moreover, the production of these substances did not correlate with enhanced growth on bean seedlings, measured as the combined increase in length of roots and aerial parts in the V3 stage of growth. Seven Trichoderma isolates significantly improved the growth of bean seedlings. However, metabolite production varied widely in these seven strains, and some isolates did not produce any of the assessed growth-promoting metabolites. Results indicated that growth was enhanced in the presence of rhizosphere competent and endophytic strains of Trichoderma, and these characteristics were strain-specific and not characteristic for species. 相似文献
10.
Seymour FA Cresswell JE Fisher PJ Lappin-Scott HM Haag H Talbot NJ 《Fungal genetics and biology : FG & B》2004,41(7):721-734
The relationship between metabolite production and genotypic diversity in two endophytic fungi was investigated. We selected populations of Cylindrocarpon destructans and Heliscus lugdunensis from the roots of a single tree. A total of 49 isolates of both species were selected and classified by simple genotypic tests (random amplified polymorphic DNA analysis and rDNA-ITS sequencing). In a blind test, the ability of these fungi to produce natural products was tested by ethyl acetate extraction of hyphae and culture filtrates, followed by high-performance liquid chromatography analysis (HPLC). A positive relationship was found between genotype classification and the pattern of natural products produced by a given isolate. To test the robustness of this correlation, a discriminate selection procedure was carried out by collecting fungal isolates from a second site and selecting a sub-set of the population, on the basis of genotypic variability. This sub-set of fungal isolates produced greater numbers of unique metabolites than those selected indiscriminately. 相似文献
11.
T. V. Antipova V. P. Zhelifonova B. P. Baskunov S. M. Ozerskaya N. E. Ivanushkina A. G. Kozlovsky 《Applied Biochemistry and Microbiology》2011,47(3):288-292
Screening of producers of secondary metabolites was carried out among 25 fungal strains of Penicillium genus isolated from permafrost in Arctic and Antarctic regions and Kamchatka. Nearly 50% of the investigated strains synthesize
biologically active substances of alkaloid nature: ergot alkaloids, diketopiperazinees, and quinoline derivatives. A large
group of the identified metabolites belongs to mycotoxins. A strain of Penicillium waksmanii was found producing epoxyagroclavine-I and quinocitrinines. The main physiological and biochemical characteristics of this
producer were investigated. 相似文献
12.
红曲菌次生代谢产物生物合成途径及相关基因的研究进展 总被引:1,自引:0,他引:1
红曲菌(Monascus spp.)是我国重要的药食两用微生物资源之一,能够产生天然食品添加剂红曲色素、降血酯活性物质Monacolin K等有益次生代谢产物,但也能分泌真菌毒素桔霉素(Citrinin),红曲菌及其相关产品的安全性由此受到质疑.因此,如何促进红曲菌有益代谢产物的产生,减少或抑制桔霉素的产生成为广大科研工作者研究的重点方向.近年来,红曲菌的分子生物学研究有了较快的发展,红曲菌次生代谢产物生物合成及其调控的研究是热点.本文重点介绍红曲色素、Monacolin K和桔霉素生物合成途径及相关基因的研究进展,以期为有效调控红曲菌次生代谢产物的产生、提高红曲产品的安全性提供参考和借鉴. 相似文献
13.
S. S. M. El-Maraghy 《Folia microbiologica》1996,41(1):53-60
Fungi of 19 genera, 30 species, and one variety were isolated from 25 samples of sheep-, cattle- and camel feedstuffs collected
from different farms in the Beida Governorate, Libya.Aspergillus, Penicillium andFusarium were the most common genera in the three substrates tested. TLC was used to establish the identity of aflatoxins in the chloroform
extract of all samples and the ability to produce aflatoxins byAspergillus flavus in a synthetic liquid medium. Twenty samples out of 25 tested were naturally contaminated and 21 isolates ofA. flavus out of 30 produced at least one of the following aflatoxins: B1; B1, G1; and B1, B2, G1, G2. This is the first report about the natural occurrence of aflatoxins and aflatoxin-producers of the genusAspergillus in Libya. 相似文献
14.
Hiroshi Hitokoto Satoshi Morozumi Tomoaki Wauke Senzo Sakai Hiroshi Kurata 《Mycopathologia》1981,73(1):33-38
A total of 604 samples of about 7 different types of beans was examined to determine their mycological profiles, and suitability for use as solid substrates for mycotoxin production.All of the samples were collected from bean jam makers in Tokyo by the official food examiners.Genera Penicillium and Aspergillus were predominant, and genus Wallemia was also found commonly in all types of beans.Mycotoxin-producing Aspergillus strains were isolated from 52 samples of beans, approximately 9% of the total. The highest incidence of toxigenic Aspergillus (14.1%) was found in kidney beans. Red beans and peas inoculated with Aspergillus ochraceus were found to produce about 7 to 8 times more toxin than was obtained in a liquid medium, and red beans inoculated with A. versicolor produced more toxin than was obtained in yeast extract sucrose broth. Green peas inoculated with Fusarium graminearum produced about 8 times more T-2 toxin than was obtained in 1% peptone containing Czapek solution under comparable culture conditions. 相似文献
15.
Imazalil tolerant isolates ofPenicillium spp. were recovered from sampling natural spore populations in storage rooms and apples collected from packinghouses in Lleida (Spain). ThePenicillium resistant strains belong to the speciesP. cyaneofulvum, P. variabile, P. rugulosum, P. minioluteum andP. pinophilum. 85% of the tested strains were resistant to imazalil in final concentrations of imazalil ranging from 4,500 µg/ml to 11,000 µg/ml. The resistance of these moulds to this fungicide was constant during successive subcultures. 89% ofPenicillium studied strains produced decay in the determination of parasitic fitness at 10 days. 相似文献
16.
Samira Badri Aziz Fassouane Ingrid Filliol Mohammed Hassar Nozha Cohen 《Journal of microbiology (Seoul, Korea)》2010,48(2):184-187
In order to develop other molecular method useful for typing of motile and non motile Escherichia coli strains, a total of 207 strains of E. coli (133 reference strains, 74 food strains) were characterized by analysis of sequences of their amplified flagellin-encoding
(fliC) gene products. The collection of reference strains was used for database building of fliC gene sequences. Application of this identification system to 74 E. coli food isolates revealed a reproducible and clear cut classification with very good correlation to results obtained by HhaI restriction of the amplified flagellin gene. The proposed determination of fliC sequences variations should be helpful for epidemiological studies. 相似文献
17.
Aims: To assess the ability of fungi isolated from grapes to produce patulin and citrinin. Methods and Results: A total of 446 Aspergillus isolates belonging to 20 species and 101 Penicillium isolates were inoculated in Czapek yeast extract agar and yeast extract sucrose agar and incubated for 7 days at 25°C. Extracts were analysed for patulin and citrinin by thin‐layer chromatography. None of the isolates of Aspergillus spp. produced either patulin or citrinin. Patulin was produced by three isolates of Penicillium expansum and two of Penicillium griseofulvum. Citrinin was produced by five isolates of P. expansum, two of Penicillium citrinum and one of Penicillium verrucosum. Conclusions: Our results show that the Aspergillus and Penicillium species commonly isolated from grapes are not a source of the mycotoxins, patulin and citrinin. Significance and Impact of the Study: The possibility of co‐occurrence of patulin and citrinin with ochratoxin A in grapes and grape products remain low, owing to the low frequency of isolation of potentially producing species. 相似文献
18.
Johan L. F. Kock Dennis J. Coetzee Martie S. van Dyk Michelle Truscott Alfred Botha Ockert P. H. Augustyn 《Antonie van Leeuwenhoek》1992,62(4):251-259
By using specific inhibitors of the lipoxygenase and cyclo-oxygenase pathways, arachidonic acid metabolites with similar sensitivities towards these inhibitors as in humans, were detected inDipodascopsis uninucleata. The taxonomic value of aspirin sensitive arachidonic acid metabolites in the Lipomycetaceae was next assessed. No metabolites of which the production is inhibited by aspirin were detected in strains representing the following species:Lipomyces starkeyi, Lipomyces kononenkoae, Lipomyces tetrasporus, Myxozyma melibiosi, Myxozyma mucilagina, Myxozyma kluyveri, Waltomyces lipofer, Zygozyma oligophaga andZygozyma arxii. The detection of such aspirin sensitive arachidonic acid metabolites in representative strains ofLipomyces anomalus and the genusDipodascopsis, emphasises the isolated position of these taxa in the genusLipomyces and the family Lipomycetaceae, respectively. Finally using long chain fatty acid analyses, electrophoretic karyotyping and other phenotypic characters, a phylogenetic scheme is proposed for some genera in the Lipomycetaceae. 相似文献
19.
20.
Tom van den Brule Maarten Punt Wieke Teertstra Jos Houbraken Han Wösten Jan Dijksterhuis 《Environmental microbiology》2020,22(3):986-999
Fungi colonize habitats by means of spores. These cells are stress-resistant compared with growing fungal cells. Fungal conidia, asexual spores, formed by cosmopolitan fungal genera like Penicillium, Aspergillus and Peacilomyces are dispersed by air. They are present in places where food products are stored and as a result, they cause food spoilage. Here, we determined the heterogeneity of heat resistance of conidia between and within strains of Paecilomyces variotii, a spoiler of foods such as margarine, fruit juices, canned fruits and non-carbonized sodas. Out of 108 strains, 31 isolates showed a conidial survival >10% after a 10-min-heat treatment at 59°C. Three strains with different conidial heat resistance were selected for further phenotyping. Conidia of DTO 212-C5 and DTO 032-I3 showed 0.3% and 2.6% survival in the screening respectively, while survival of DTO 217-A2 conidia was >10%. The decimal reduction times of these strains at 60°C (D60 value) were 3.7 ± 0.08, 5.5 ± 0.35 and 22.9 ± 2.00 min respectively. Further in-depth analysis revealed that the three strains showed differences in morphology, spore size distributions, compatible solute compositions and growth under salt stress. Conidia of DTO 217-A2 are the most heat-resistant reported so far. The ecological consequences of this heterogeneity of resistance, including food spoilage, are discussed. 相似文献