Growth and spore production of Plectosporium tabacinum

2001 ◽  
Vol 79 (11) ◽  
pp. 1297-1306 ◽  
Author(s):  
Wenming Zhang ◽  
Michelle Sulz ◽  
Karen L Bailey

Plectosporium tabacinum (van Beyma) M.E. Palm, W. Gams, et Nirenberg has been evaluated as a bioherbicide for the control of Galium spurium L. (false cleavers). Little is known, however, about the specific culture and sporulation requirements of this fungus on standard agar media. In addition, information on submerged liquid culture spore production is not available. This information is important for the successful culture and further development of this fungus as a biocontrol agent. This study characterized mycelial growth and sporulation of Plectosporium tabacinum on 14 different standard agar media over a range of light regimes, pH, and temperatures. Conditions required for submerged liquid culture spore production and resulting weed control efficacy were also assessed. This included the effect of liquid culture medium and pH and the effect of carbon source, nitrogen source, carbon concentration, and carbon–nitrogen (C:N) ratio. Potato dextrose agar is the best agar medium for growth and spore production. On standard agar media, growth and spore production was not influenced by light regime. Medium pH did not affect mycelial growth and spore germination but the optimal pH for spore production was 7.0. The optimal temperature for the mycelial growth was between 22 and 25°C, but the optimal temperature for spore production was at either 20 or 30°C, depending upon the nutrient medium. Temperatures above 20°C were required to achieve greater than 90% spore germination. For submerged liquid culture spore production, Richard's solution (RS) is the best liquid medium for spore production. The optimal pH was 7.0 for RS but varied with culture media. Potassium nitrate and corn starch were the best nitrogen source and carbon source, respectively. A medium with a carbon concentration of 12.6 g/L and a C:N ratio of 7.5:1 is optimum for spore production and weed control efficacy.Key words: Plectosporium tabacinum, bioherbicide, mass production, fermentation, false cleavers, Galium spurium.

1976 ◽  
Vol 39 (3) ◽  
pp. 170-174 ◽  
Author(s):  
M. D. NORTHOLT ◽  
C. A. H. VERHULSDONK ◽  
P. S S. SOENTORO ◽  
W. E. PAULSCH

The effect of water activity (aw) on growth and aflatoxin production by Aspergillus parasiticus NRRL 2999 was determined using submerged cultures in which the aw was adjusted by addition of glycerine, glucose, or a mixture of salts. At a sub-optimal aw aflatoxin production was low in the glycerol and glucose media while no strong inhibition of mycelial growth occurred. A similar effect was obtained in surface cultures on agar media in which the aw was adjusted by addition of glycerine or sucrose. The effect of a sub-optimal temperature was the reverse; compared to inhibition of mycelial growth in surface cultures, the effect on aflatoxin production was slight. No detectable quantities of aflatoxin B1 were formed at 0.83 aw and at 10 C nor at four combinations of higher aw and temperature. The aw was measured by a recently developed device using the dewpoint principle.


2019 ◽  
Vol 7 (2) ◽  
pp. 31 ◽  
Author(s):  
Tatiane Araujo Gonzales ◽  
Lucielen Oliveira dos Santos ◽  
Beatriz Torsani Ubeda ◽  
Ranulfo Monte Alegre ◽  
Rosana Goldbeck

In this work, the effects of different carbon:nitrogen (C:N) ratios, carbon source and initial carbon concentration, in liquid medium used for submerged fermentation, on biomass growth, succinic acid production and yield of product in substrate (YP/S) were studied. It was used three carbon sources as substrate such as glucose, xylose and sucrose and the C:N ratios studied were in the range of 2.5-35. The succinic acid production was best at a C:N ratio of 12.5:1, as much for the succinic acid production as for the yield of product in relation to the substrate (YP/S). For the biomass growth the C:N ratios of 2.5:1, 5:1 and 10:1 had only presented significant difference with regards to the too much assays. The substrate that presents the best results was the glucose with succinic acid concentrations up to 7.5 g.L-1.


Weed Science ◽  
1992 ◽  
Vol 40 (3) ◽  
pp. 497-502 ◽  
Author(s):  
Michael K. Kawate ◽  
Susan C. Kawate ◽  
Alex G. Ogg ◽  
John M. Kraft

The effect of glyphosate on growth and reproduction of two pathogenic fungi of green peas was evaluated in laboratory studies. Liquid and agar media containing 0 to 50 mM glyphosate were inoculated with two isolates each ofFusarium solanif. sp.pisiandPythium ultimum.Mycelial growth and spore production of the fungi were inhibited or stimulated by glyphosate, depending on concentration. Glyphosate did not affect pathogenicity ofF. solanif. sp.pisi.The effect of glyphosate on pathogenicity ofP. ultimumwas not determined. Under field conditions, glyphosate probably would not affect pathogenicity or survival of either fungus.


2003 ◽  
Vol 81 (12) ◽  
pp. 1285-1292 ◽  
Author(s):  
Takefumi Hattori ◽  
Akira Ohta ◽  
Masayuki Itaya ◽  
Mikio Shimada

We have investigated growth of ectomycorrhizal (ECM) fungi (i.e., 55 strains of 32 species in 15 genera) on saturated (palmitate), monounsaturated (oleate), diunsaturated (linoleate), triunsaturated (linolenate) fatty acids, and the triacylglyceride of oleate (triolein) lipid to elucidate an ability to utilize the fatty acids and lipid as a carbon source for growth. Relative utilization ratios (URs, %) based on mycelial growth on glucose suggest that ECM fungi belonging to the family Thelephoraceae have an ability to utilize palmitate. On the other hand, ECM fungi in the genus Laccaria can utilize at least either palmitate or oleate. Furthermore, Hygropharus russula grows on palmitate, oleate, and slightly on triolein. Lactarius chrysorrheus grows only on palmitate. These fatty-acid- and lipid-utilizing fungi may be promising as model fungi for further elucidation of the metabolic ability to utilize the fatty acids and lipid as a carbon source. On the contrary, the fungi in the genus Suillus were shown to scarcely utilize the fatty acids and lipid. Furthermore, most ECM fungi did not grow on either linoleate or linolenate.Key words: carbon source, ectomycorrhizal fungi, fatty acid, lipid, mycelial growth.


2009 ◽  
Vol 3 (2) ◽  
pp. 41-52
Author(s):  
Rasha T. Abdullah ◽  
Abdulkareem J. Hashim ◽  
JASIM M. Karhout

The keratinase produced from local isolate Bacillus licheniformis was purified by two steps included precipitation by ammonium sulphate with 40% saturation; followed by ion exchange using CM-Cellulose column. The enzyme was purified to 12.6 times in the last step with an enzyme yield of 17%. Enzyme characterization results indicated that: The optimal pH for enzyme activity was 7.5 and it was stable at 7-9.5. The optimal temperature for enzyme activity was 50°C and it was stable for 30 min at 25-45 °C. Substrate specifity was tested using casein, Bovine serum albumin, gelatin, hooves, human hair, chicken feathers and wool; higher specifity was recorded using casein gave 0.6 unit /ml. The enzyme was inhibited by PMSF and metal ions like Hg+2, Fe+2, Cu+2 and Mn+2, and activated by Ca+2, Mg+2, Zn+2and Al+3.


2020 ◽  
Vol 31 (1) ◽  
pp. 15
Author(s):  
Dr.Neihaya Heikmat Zaki

Twenty five samples were collected from the soil around the Tigris River from different locations in Iraqi cities, and 45 bacterial isolates were obtained. Three of these isolates were further tested for their degrading capacity of Bisphenol A (BPA) in Basal Mineral Medium, included: Pseudomonas orizohibtanis, Escherishia coli and Proteus penneri. The optimal temperature for the removal of BPA was determined at 20˚C, 37˚ and 45˚C for 1, 5, and 15 days, and the degradation increased up to a temperature of 37°C. Growth test was performed on isolated bacteria with BisPhenol A as the sole carbon source, and with increasing incubation time, the culture grew almost linearly to 24 hours. BPA decreased after 1days after incubating with tested bacterial isolates, and almost broken after 5 days, while it disappeared after 15 days at 37C, and Pseudomonas orizohibtanis exhibited the best degradation of BPA. The absorbance peaks in the UV region appeared at 222 and 276 nm and attributed to the benzene ring and triazine ring respectively. The end products of BPA degradation were analyzed by GCMS after 15 days of incubation. The chromatogram for Pseudomanas orizohibtanis showed three peaks at retention times of 70, 210 and 280 min, and referred to hexasiloxane, heptasiloxane, and Octasiloxane respectively. The present study was aimed to isolate bacteria from the soil of the Tigris River, and determined the ability to degrade Bisphenol-A, and characterized the environmental conditions of bacterial growth, and then analysis the products of the degradation by GC-MS.


1988 ◽  
Vol 34 (6) ◽  
pp. 818-822 ◽  
Author(s):  
V. Juillard ◽  
M. J. Desmazeaud ◽  
H. E. Spinnler

In Streptococcus thermophilus CNRZ 404, the presence of urease activity was demonstrated by means of a specific colorimetric method for ammonium ions. The main physicochemical properties of the enzyme were determined. The Km with urea as substrate was 1.19 mM and the optimal pH was approximately 7.5. Because both thermolability and enzyme activity increased as the temperature was increased to 70 °C, the optimal temperature could not be determined with precision. Urease activity was maximal at the beginning of the stationary growth phase; it was stimulated by the presence of urea and of certain amino acids such as arginine and glutamic acid in the culture medium. This activity has been detected in several other strains of Streptococcus thermophilus. [Translated by the journal]


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Carlos Alfonso Frías-Quintana ◽  
Emyr Saul Peña-Marín ◽  
Carlos David Ramírez-Custodio ◽  
Rafael Martínez-García ◽  
Luis Daniel Jiménez-Martínez ◽  
...  

ABSTRACT In the Southeast of Mexico, there are many native cichlids with commercial interest such as redhead cichlid (Vieja melanurus) and twoband cichlid (V. bifasciata), which have a great local demand and excellent meat quality. However, it is necessary to implement their culture based on nutrition studies and digestive biochemistry. This study’s objective was to characterize these two cichlids’ digestive proteases (pH, temperature, and inhibitors) through biochemistry techniques. Results showed that V. melanurus and V. bifasciata have a digestive capacity analogous to other omnivore fishes, where the optimal pH values of stomach proteases (4 and 2, respectively) and intestinal proteases (6 and 12, respectively), the optimal temperature of acid (35°C and 55°C, respectively) and alkaline proteases (45°C and 55°C, respectively) are quite similar. Both species presented high thermal and pH stabilities. Inhibition showed that V. melanurus is more sensitive to specific inhibitors for alkaline proteases than V. bifasciata. In conclusion, V. bisfasciata and V. melanurus have different digestive protease patterns. Both species can hydrolyze different protein ingredients to formulate a specific diet. Nevertheless, V. bifasciata is more resistant to the presence of inhibitors, which allow it to include vegetable proteins in its diet.


2010 ◽  
Vol 56 (12) ◽  
pp. 979-986 ◽  
Author(s):  
E. Tang ◽  
C.B. Hill ◽  
G.L. Hartman

Fusarium virguliforme is the cause of sudden death syndrome in soybean. Physiological variability among isolates of the fungus is unknown. One way to measure physiologic variability is to analyze growth on different carbon sources. The carbon source utilization profiles of 18 F. virguliforme isolates were examined using the Biolog FF 96-well microplate, which contains 95 different carbon sources. The utilization of dextrin, d-mannitol, maltotriose, d-lactic acid methyl ester, N-acetyl-d-galactosamine, salicin, d-trehalose, and l-alanine differed significantly among isolates (P = 0.05). Carbon sources were grouped into 3 clusters based on their ability to promote growth of F. virguliforme, after calculating Euclidean distances among them. About 12% of the carbon sources promoted a high amount of mycelial growth, 39% promoted a medium amount of growth, and 49% promoted a low amount of mycelial growth; the latter was not significantly different from the water blank control. A hierarchical tree diagram was produced for the 18 isolates based on their carbon source utilization profiles using Ward’s hierarchical analysis method. Two main clusters of isolates were formed. One cluster represented greater average mycelial growth on all of the carbon sources than the other cluster. In this study, variability in carbon source utilization among F. virguliforme isolates was evident, but the results were not associated with geographic origin of the isolates, year collected, or published data on aggressiveness. Additional research is needed to determine if these carbon utilization profiles are associated with other biological characteristics, like spore germination, propagule formation, and saprophytic competitiveness.


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