scholarly journals Comparative Ergot Alkaloid Elaboration by Selected Plectenchymatic Mycelia of Claviceps purpurea through Sequential Cycles of Axenic Culture and Plant Parasitism

Biology ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 41
Author(s):  
Peter Mantle
Keyword(s):  
Present Report ◽  
Axenic Culture ◽  
Ergot Alkaloids ◽  
Culture Conditions ◽  
Claviceps Purpurea ◽  
Classical Concept ◽  
Industrial Fermentation ◽  
Plant Parasitism ◽  
Key Factor ◽  
Selection Of

Ergot alkaloids have an established place in plant pathology and toxicology. As pharmaceuticals, their sourcing is via natural or managed agricultural occurrence of sclerotia of Claviceps purpurea (Fr.) Tul. or through industrial fermentation processes with other Claviceps. The key factor for biosynthesis is differentiation of a particular mycelial anatomy. Previous study of these fungi from two disparate English grass genera, Spartina and Phragmites, has shown that only mycelia expressing a plectenchymatic sclerotium-like anatomy in specific axenic culture conditions elaborated ergot alkaloids, and then only as far as lysergic acid. The present report describes sequential cycles of axenic and parasitic cultivation for wild isolates from Dactylis and Alopecurus with intervention of a single ascospore step. This confirms the homozygous character of C. purpurea and defines several potential experimental axenic and parasitic conditions within the species for comparing genomic aspects of partial or full biosynthesis of cyclic tri-peptide alkaloids. Whereas Alopecurus ergot isolates readily parasitized rye, use of Dactylis isolates as inoculum for rye ovaries failed to cause the usual sphacelial fructification but supported growth of exceptionally thin sclerotia, sometimes two in a floret, with low alkaloid content attributed to reduced medullary component. However, after two cycles of axenic and rye-parasitic cultivation, and consistent re-selection of the plectenchymatic character in axenic mycelia, typical growth of ergot sclerotia occurred on rye. Caution thus seems necessary in tests for putative host specificity in any taxonomic realignments within the classical concept of C. purpurea. A Dactylis ergot isolate was also uniquely shown to parasitise the plumule of germinating rye seeds confirming the susceptibility of apical tissues. A key biosynthetic feature of a mycelial glyceride oil, rich in ricinoleic acid, as a prelude to axenic and parasitic formation of ergot alkaloids by C. purpurea is emphasised.

IN VITRO PRODUCTION OF ERGOT ALKALOIDS BY CULTURES OF CLAVICEPS PURPUREA (FR.) TUL.

1957 ◽  
Vol 3 (1) ◽  
pp. 55-60 ◽  
Author(s):  
W. A. Taber ◽  
L. C. Vining
Keyword(s):  
Liquid Medium ◽  
Incubation Period ◽  
Ergot Alkaloids ◽  
Claviceps Purpurea ◽  
In Vitro Production ◽  
Factors Influencing ◽  
Ammonium Succinate ◽  
Vitro Production ◽  
Selection Of

Stationary cultures of Claviceps purpurea (Fr.) Tul. grown 50 days on a liquid medium containing mannitol, ammonium succinate, and salts produced small amounts of ergot alkaloids.Ergometrine, ergometrinine, ergotamine, ergotaminine, ergocornine, ergocorninine, ergocryptine, agroclavine, and penniclavine were identified by paper chromatography of culture extracts. The selection of strains, the composition of the medium, and the length of the incubation period appeared to be important factors influencing the production of alkaloids.

scholarly journals Alkaloid Cluster Gene ccsA of the Ergot Fungus Claviceps purpurea Encodes Chanoclavine I Synthase, a Flavin Adenine Dinucleotide-Containing Oxidoreductase Mediating the Transformation of N-Methyl-Dimethylallyltryptophan to Chanoclavine I

2010 ◽  
Vol 76 (6) ◽  
pp. 1822-1830 ◽  
Author(s):  
Nicole Lorenz ◽  
Jana Olšovská ◽  
Miroslav Šulc ◽  
Paul Tudzynski
Keyword(s):  
Flavin Adenine Dinucleotide ◽  
Axenic Culture ◽  
Ergot Alkaloids ◽  
Claviceps Purpurea ◽  
Alkaloid Biosynthesis ◽  
Fusion Construct ◽  
Knockout Mutants ◽  
Clavine Alkaloids ◽  
Functional Analyses ◽  
Layer Chromatography

ABSTRACT Ergot alkaloids are indole-derived secondary metabolites synthesized by the phytopathogenic ascomycete Claviceps purpurea. In wild-type strains, they are exclusively produced in the sclerotium, a hibernation structure; for biotechnological applications, submerse production strains have been generated by mutagenesis. It was shown previously that the enzymes specific for alkaloid biosynthesis are encoded by a gene cluster of 68.5 kb. This ergot alkaloid cluster consists of 14 genes coregulated and expressed under alkaloid-producing conditions. Although the role of some of the cluster genes in alkaloid biosynthesis could be confirmed by a targeted knockout approach, further functional analyses are needed, especially concerning the early pathway-specific steps up to the production of clavine alkaloids. Therefore, the gene ccsA, originally named easE and preliminarily annotated as coding for a flavin adenine dinucleotide-containing oxidoreductase, was deleted in the C. purpurea strain P1, which is able to synthesize ergot alkaloids in axenic culture. Five independent knockout mutants were analyzed with regard to alkaloid-producing capability. Thin-layer chromatography (TLC), ultrapressure liquid chromatography (UPLC), and mass spectrometry (MS) analyses revealed accumulation of N-methyl-dimethylallyltryptophan (Me-DMAT) and traces of dimethylallyltryptophan (DMAT), the first pathway-specific intermediate. Since other alkaloid intermediates could not be detected, we conclude that deletion of ccsA led to a block in alkaloid biosynthesis beyond Me-DMAT formation. Complementation with a ccsA/gfp fusion construct restored alkaloid biosynthesis. These data indicate that ccsA encodes the chanoclavine I synthase or a component thereof catalyzing the conversion of N-methyl-dimethylallyltryptophan to chanoclavine I.

The benefits of applied research: 37 years of discoveries, adaptations and solutions

2015 ◽  
pp. 209-216 ◽  
Author(s):  
Eduardo P. Borges ◽  
Mário L. Lopes ◽  
Claudemir Bernardino ◽  
Alexandre Godoy ◽  
Fernando E. Ré ◽  
...  
Keyword(s):  
Mitochondrial Dna ◽  
Statistical Analysis ◽  
Applied Research ◽  
Sugar Production ◽  
Industrial Fermentation ◽  
Yeast Strains ◽  
Aconitic Acid ◽  
Key Factor ◽  
Cane Quality ◽  
Dry Substance

The authors’ work started in fermentation in 1977 and in the 1980’s into sugar production and cane quality. Statistical analysis was a key factor for the success of improving yield in ethanol and sugar production as well as cane quality. Adaption of methods for industrial laboratories also was very important in relation to yield and in reduction of sugar losses in the factory. Methodologies to measure sugar losses occurring through degradation in the factory (evaporation) using ion chromatography and dry substance content with a digital density meter were adapted. The fermentation yield improved from 75% in 1977 to 92% in 2014, which was possible by adapting methods for live bacterial counting within 20 min, and by controlling contamination using antimicrobial products through research in the laboratory and the industry. Since 1990 yeasts for industrial fermentation were selected by karyotyping analysis of the nuclear chromosomes and in the last seven years based on mitochondrial DNA. The last technique made the “Process Driven Selection” possible, i.e. one or several yeast strains which fit each distillery. Floc formation in carbonated beverages is not only due to the Indicator Value (discovery by SPRI research group) but also to aconitic acid and calcium under Brazilian conditions.

scholarly journals Procedure for the Selection of Rubber Compound in Rubber-Metal Springs for Vibration Isolation

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1737
Author(s):  
Milan Banić ◽  
Dušan Stamenković ◽  
Aleksandar Miltenović ◽  
Dragan Jovanović ◽  
Milan Tica
Keyword(s):  
Numerical Simulation ◽  
Constitutive Model ◽  
Vibration Isolation ◽  
Correct Selection ◽  
Virtual Experiment ◽  
Rubber Compound ◽  
Key Factor ◽  
Railway Engineering ◽  
Selection Of

The selection of a rubber compound has a determining influence on the final characteristics of rubber-metal springs. Therefore, the correct selection of a rubber compound is a key factor for development of rubber-metal vibration isolation springs with required characteristics. The procedure for the selection of the rubber compound for vibration isolation of rubber-metal springs has been proposed, so that the rubber-metal elements have the necessary characteristics, especially in terms of deflection. The procedure is based on numerical simulation of spring deflection with Bergström-Boyce constitutive model in virtual experiment, with a goal to determine which parameters of the constitutive model will lead to spring required deflection. The procedure was verified by case study defined to select rubber compound for a rubber–metal spring used in railway engineering.

scholarly journals Ergot Alkaloids in Wheat and Rye Derived Products in Italy

Foods ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 150 ◽  
Author(s):  
Francesca Debegnach ◽  
Simona Patriarca ◽  
Carlo Brera ◽  
Emanuela Gregori ◽  
Elisa Sonego ◽  
...  
Keyword(s):  
Durum Wheat ◽  
Middle Ages ◽  
Plant Pathogen ◽  
Ergot Alkaloids ◽  
Cereal Grains ◽  
Wheat Bread ◽  
Claviceps Purpurea ◽  
Eu Commission ◽  
Ongoing Monitoring ◽  
The Eu

Genus Claviceps is a plant pathogen able to produce a group of toxins, ergot alkaloids (EAs), whose effects have been known since the Middle Ages (ergotism). Claviceps purpurea is the most important representative specie, known to infect more than 400 monocotyledonous plants including economically important cereal grains (e.g., rye, wheat, triticale). EAs are not regulated as such. Maximum limits are in the pipeline of the EU Commission while at present ergot sclerotia content is set by the Regulation (EC) No. 1881/2006 in unprocessed cereals (0.05% as a maximum). This study aimed to investigate the presence of the six principal EAs (ergometrine, ergosine, ergocornine, α-ergocryptine, ergotamine and ergocristine) and their relative epimers (-inine forms) in rye- and wheat-based products. Of the samples, 85% resulted positive for at least one of the EAs. Wheat bread was the product with the highest number of positivity (56%), followed by wheat flour (26%). Rye and wheat bread samples showed the highest values when the sum of the EAs was considered, and durum wheat bread was the more contaminated sample (1142.6 μg/kg). These results suggest that ongoing monitoring of EAs in food products is critical until maximum limits are set.

scholarly journals Assessment of ergot (Claviceps purpurea) exposure in pregnant and postpartum beef cows

2018 ◽  
Vol 98 (4) ◽  
pp. 688-700 ◽  
Author(s):  
T. Grusie ◽  
V. Cowan ◽  
J. Singh ◽  
J. McKinnon ◽  
B. Blakley
Keyword(s):  
Ergot Alkaloid ◽  
Post Partum ◽  
Ergot Alkaloids ◽  
Maximum Size ◽  
Beef Cows ◽  
Plasma Prolactin ◽  
Claviceps Purpurea ◽  
Ambient Temperatures ◽  
Beef Cow ◽  
The Impact

Cows were fed ration for 9 wk containing 5, 48, 201, and 822 μg kg−1 ergot alkaloids. The objective was to evaluate the impact of ergot consumption in beef cow–calf operations. Ergot alkaloids up to 822 μg kg−1 did not alter the weight of peripartum and postpartum beef cows (P = 0.93) or nursing calves (P = 0.08), rectal temperature (P = 0.16), or plasma prolactin concentrations (P = 0.30) at moderate ambient temperatures. Ergot did not influence the time (>1 ng mL−1; P = 0.79) or the progesterone concentration (P = 0.38) at the time of first postpartum rise or the size of the first (14 ± 0.6 mm; P = 0.40) and second (13 ± 0.5 mm; P = 0.41) follicles to ovulate. The maximum size of the first postpartum corpus luteum (CL) was 4 mm larger in the 822 μg kg−1 ergot group compared with the control (P = 0.03) for the first ovulation post partum, but not for the second (P = 0.11). There was no effect of ergot exposure on the number of days until the appearance of the first (43 ± 4 d; P = 0.95) or second (52 ± 4 d; P = 0.98) CL post partum. Ergot alkaloid concentrations up to 822 μg kg−1 did not affect pregnancy rates (X2 = 0.36). In conclusion, ergot alkaloid exposure for 9 wk to concentrations as high as 822 μg kg−1 did not alter performance in pregnant and postpartum beef cattle at moderate ambient temperatures.

scholarly journals Selection of Adequate Species for Degraded Areas by Oil‐Exploitation Industry as a Key Factor for Recovery Forest in the Ecuadorian Amazon

2016 ◽  
Vol 27 (7) ◽  
pp. 1771-1780 ◽  
Author(s):  
Jaime Villacís ◽  
Cristina Armas ◽  
Susana Hang ◽  
Fernando Casanoves
Keyword(s):  
Oil Exploitation ◽  
Ecuadorian Amazon ◽  
Key Factor ◽  
Selection Of

scholarly journals COMPARATIVE ANALYSIS OF THE LEVEL OF STUDENTS` ACADEMIC MOTIVATION TO SOFIA UNIVERSITY „ST. KLIMENT OHRIDSKI” AND NATIONAL ACADEMIA OF SPORT „VASIL LEVSKI”

2019 ◽  
Vol 34 (2) ◽  
pp. 571-578
Author(s):  
Georgi Ignatov ◽  
Iliana Petkova
Keyword(s):  
Comparative Analysis ◽  
Physical Education ◽  
Young People ◽  
Learning Process ◽  
Academic Motivation ◽  
Present Report ◽  
Theoretical Background ◽  
Active Involvement ◽  
Additional Information ◽  
Key Factor

The present report addresses a topic that is a key factor for the quality of the education in universities. The outcome this education depends on the degree of students’ academic motivation and results in their readiness for certain profession. The material presents the results from a study conducted in the period 2016-2019 among 45 students in their second and third year of studies in the subject „Physical Education and Sport“ at the Sofia University „St. Kliment Ohridski“ Faculty of Science, Education and Arts and 39 students also studying „Physical Education“ but at the National Sports Academy „Vasil Levski“ Faculty of Pedagogy. As a research tool, was used a questionnaire designed for determining the academic motivation, developed by Angel Velichkov. The questionnaire contained 11 questions, of which 7 with positive and 4 with negative direction. The assessment was done through the 4-point Likert scale, where 0 is „completely disagree” and 3 is „completely agree”. In his work A. Velichkov places the degree of academic motivation within the following limits: 0-11 points – lack of academic motivation; 12-18 points – weak motivation; 19-24 points – moderate motivation, 25-33 points – strong academic motivation. The summaries are made both on universities and on each individual indicator for academic motivation, including: „Active attitude to the learning process“, „Internal self-discipline“ and „Strive to complement and broaden the obtained knowledge“. To determine the priorities of young people, we divided their statements that received the highest percentage of opinions „agree“ on the positively formulated questions and „disagree“ on the negative ones. The comparative analysis shows that the overall degree of academic motivation is not high among students from both Universities. However, students in both universities are convinced that active involvement in the learning process is required. Students are aware of the importance of the theoretical background they need to acquire during their studies. They are motivated to gain lasting knowledge and excellence in all subjects studied. Young people indicate that they complement and broaden their knowledge by seeking additional information and by consultations with university professors.

scholarly journals Screening of Amazonian bacillus strains for lipase production using glycerol as substrate

ScientiaTec ◽  
2020 ◽  
Vol 7 (03) ◽  
Author(s):  
Giandra Volpato ◽  
Victória Furtado Migliavacca ◽  
Bruna Coelho de Andrade ◽  
Júlio Xandro Heck ◽  
Marco Antônio Záchia Ayub
Keyword(s):  
Organic Synthesis ◽  
Culture Medium ◽  
Lipolytic Activity ◽  
Gum Arabic ◽  
Lipase Production ◽  
Culture Conditions ◽  
Search And Selection ◽  
Triton X ◽  
Potential Use ◽  
Selection Of

The industrial application of lipolytic enzymes has been studied mainly due to the ability of these enzymes in catalyze reactions of synthesis and their stability in various organic solvents. One possibility is the use of lipase the organic synthesis, taking advantage as the generation of waste and difficult recovery of sub bioproducts. In this work, we carried out a selection of eighty-four isolates of Bacillus amazonian for lipase production, of which 30 strains showed lipolytic activity. The study of the culture conditions was performed through a Plackett-Burman experimental design using the strain that presented the highest lipolytic activity in a culture medium using glycerol as substrate.  The studied conditions were: concentration of soybean oil, olive oil, triton X-100, gum arabic, glycerol, and (NH4)2SO4, pH, temperature and concentration of inoculums. The best result obtained were 27 U/L in 48 h of cultivation by Bacillus circulans BL53. This work shows that the search and selection of microorganism with lipolytic activities can facilitate the discovery of new lipases, with potential use as by-product surplus.

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