Growth Inhibition of Soil Fungi by Insecticides and Annulment of Inhibition by Yeast Extract or Nitrogenous Nutrients

ABSTRACT Identification of physiological and environmental factors that limit efficient growth of hyperthermophiles is important for practical application of these organisms to the production of useful enzymes or metabolites. During fed-batch cultivation of Sulfolobus solfataricus in medium containing l-glutamate, we observed formation of l-pyroglutamic acid (PGA). PGA formed spontaneously from l-glutamate under culture conditions (78°C and pH 3.0), and the PGA formation rate was much higher at an acidic or alkaline pH than at neutral pH. It was also found that PGA is a potent inhibitor of S. solfataricus growth. The cell growth rate was reduced by one-half by the presence of 5.1 mM PGA, and no growth was observed in the presence of 15.5 mM PGA. On the other hand, the inhibitory effect of PGA on cell growth was alleviated by addition of l-glutamate or l-aspartate to the medium. PGA was also produced from the l-glutamate in yeast extract; the PGA content increased to 8.5% (wt/wt) after 80 h of incubation of a yeast extract solution at 78°C and pH 3.0. In medium supplemented with yeast extract, cell growth was optimal in the presence of 3.0 g of yeast extract per liter, and higher yeast extract concentrations resulted in reduced cell yields. The extents of cell growth inhibition at yeast extract concentrations above the optimal concentration were correlated with the PGA concentration in the culture broth. Although other structural analogues ofl-glutamate, such as l-methionine sulfoxide, glutaric acid, succinic acid, and l-glutamic acid γ-methyl ester, also inhibited the growth of S. solfataricus, the greatest cell growth inhibition was observed with PGA. We also observed that unlike other glutamate analogues,N-acetyl-l-glutamate enhanced the growth of S. solfataricus. This compound was stable under cell culture conditions, and replacement of l-glutamate with N-acetyl-l-glutamate in the medium resulted in increased cell density.

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GROWTH INHIBITION OF TWO SAPROPHYTIC AND TWO PLANT PARASITIC SOIL FUNGI BY ANTIBIOTICS

Canadian Journal of Botany ◽

10.1139/b61-037 ◽

1961 ◽

Vol 39 (3) ◽

pp. 491-495

Author(s):

E. W. B. Ward ◽

A. W. Henry

Keyword(s):

Growth Inhibition ◽

Soil Fungi ◽

Agar Medium ◽

Trichoderma Viride ◽

Natural Soil ◽

Plant Parasitic

Comparisons were made of growth inhibition of two saprophytic (Trichoderma viride, Trichocladium asperum) and two plant parasitic soil fungi (Ophiobolus graminis, Fomes annosus) by antibiotics. The fungi were grown on an agar medium containing various concentrations of one of the antibiotics: acti-dione, gliotoxin, griseofulvin, patulin, or trichothecin. In general the two parasites tended to be more sensitive than the saprophytes, but there were several individual exceptions. Moreover, the comparative responses of the fungi at different antibiotic concentrations were frequently not proportionately related. The results are discussed in relation to the possible effects of antibiotics on fungi in natural soil.

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Antagonistic Potentiality of Some Soil Fungi Against Six Fungal Pathogens Isolated From Cotton (Gossypium Hirsutum L.) Seeds

Journal of the Asiatic Society of Bangladesh Science ◽

10.3329/jasbs.v46i2.54410 ◽

2021 ◽

Vol 46 (2) ◽

pp. 143-153

Author(s):

Amina Khatun ◽

Shamim Shamsi ◽

Abul Bashar

Keyword(s):

Gossypium Hirsutum ◽

Growth Inhibition ◽

Radial Growth ◽

Fungal Pathogens ◽

Soil Fungi ◽

The Other ◽

Dual Culture ◽

Gossypium Hirsutum L ◽

Volatile Metabolites ◽

Other Hand

The antagonistic potentials of four soil filamentous fungi viz., Aspergillus flavus Link, A. fumigatus Fresenius, A. niger van Tieghem and Trichoderma viride Pers. against six pathogens isolated from 14 varieties of cotton (Gossypium hirsutum L.) were evaluated by "dual culture colony interaction”, volatile and non-volatile metabolites. In dual culture colony interaction, out of four soil fungi, T. viride was found be the most effective to control the growth of the cotton pathogens. T. viride showed the highest growth inhibition against Curvularia lunata, Fusarium moniliforme, Mucor sp. and Rhizoctonia solani. On the other hand A. niger showed the highest growth inhibition against Fusarium nivale and A. fumigatus showed the maximum growth inhibition against C. gloeosporioides. The highest inhibition of radial growth of C. lunata, F. nivale and F. moniliforme was observed might be due to the secretion of volatile metabolites of T. viride whereas, the maximum inhibition of radial growth of C. gloeosporioides was observed because of the volatile metabolites of A. flavus. Mucor sp. and R. solani were inhibited due to the volatile metabolites of A. fumigatus. The greatest radial growth inhibition of C. lunata and F. moniliforme were noticed in case of T. viride owing to the effect of non-volatile metabolites. On the other hand, the radial growth of C. gloeosporioides and F. nivale were inhibited highest amount for the effect of non-volatile metabolites of A. niger, whereas highest growth inhibition of Mucor sp. and R. solani was observed due to the non-volatile effect of A. fumigatus. The present investigation suggests that the isolates of Aspergillus and Trichoderma may be further exploited as potential biocontrol agents against the fungal pathogens of cotton in field trial. Asiat. Soc. Bangladesh, Sci. 46(2): 143-153, December 2020

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THE APPLICATION OF A NUTRITIONAL GROUPING METHOD TO SOIL FUNGI

Canadian Journal of Botany ◽

10.1139/b55-022 ◽

1955 ◽

Vol 33 (3) ◽

pp. 281-288 ◽

Cited By ~ 6

Author(s):

R. G. Atkinson ◽

J. B. Robinson

Keyword(s):

Amino Acids ◽

Growth Factors ◽

Yeast Extract ◽

Soil Fungi ◽

Basal Medium ◽

Maximum Growth ◽

Potassium Nitrate ◽

Soil Extract ◽

Mineral Salts ◽

Soil Extracts

In tests with seven different liquid media in which the common nitrogen source was potassium nitrate and the carbohydrate substrate was glucose, at a concentration of only 0.1%, most of the 1914 soil fungi isolated fell into one of three nutritional groups requiring, respectively, for maximum growth amino acids, amino acids plus growth factors, or yeast extract. Relatively few isolates required growth factors alone or a combination of yeast and soil extracts. Most of the isolates grew poorly in the basal medium containing only mineral salts, and glucose, with or without soil extract. Although fungi requiring yeast extract were much less frequently isolated from soil on, rather than remote from, tubers grown in a soybean green-manured plot, isolates requiring amino acids, or yeast plus soil extracts, were correspondingly increased on immature and mature tubers, respectively. In a second plot, however, not specially treated, no differences were observed in the nutritional spectra of fungi isolated from the two kinds of soil environment.

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Evaluation of the heteroantagonism between Enterobacter agglomerans strains isolated from vulture (Coragyps atratus) for production and Pseudomonas aeruginosa as developed

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/s0102-09352011000300010 ◽

2011 ◽

Vol 63 (3) ◽

pp. 595-599

Author(s):

L.A. Lima ◽

C.D.L.C. Lima ◽

L.R. Carvalho ◽

M.E.B. Margutti-Pinto

Keyword(s):

Pseudomonas Aeruginosa ◽

Gastrointestinal Tract ◽

Growth Inhibition ◽

Yeast Extract ◽

Hospital Environment ◽

Enterobacter Agglomerans ◽

Experimental Conditions ◽

Positive Results

The heteroantagonism between Enterobacter agglomerans, isolated from the gastrointestinal tract of American vulture Coragyps atratus, and Pseudomonas aeruginosa isolated from a hospital environment was evaluated. The slow (layer) and the wells (direct) techniques were tested, using agar and soy tryptone broth pH 7.3 at 37ºC. Through the slow method from 196 tests, inhibition growth halos, related heteroantagonism phenomenon observed in 118, corresponding to 60.2% positive results. Equivalent positive results were detected using wells (direct) methodology. The seven samples of E. agglomerans tested were capable of revealing heteroantagonism in the experimental conditions; antagonism reveled by the presence of a clear growth inhibition halo. The added 1% yeast extract to media was adequate for revealing antagonisms best.

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Antagonistic potentials of some soil fungi against three post‐harvest pathogenic fungi of Carica papaya L.

Dhaka University Journal of Biological Sciences ◽

10.3329/dujbs.v28i1.46488 ◽

2019 ◽

Vol 28 (1) ◽

pp. 1-7

Author(s):

Rezuana Binte Helal ◽

Shamim Shamsi

Keyword(s):

Growth Inhibition ◽

Radial Growth ◽

Soil Fungi ◽

Carica Papaya ◽

Trichoderma Viride ◽

Pathogenic Fungi ◽

Dual Culture ◽

Volatile Metabolites ◽

Maximum Inhibition ◽

Fusarium Sp

Four antagonistic fungi were isolated from the papaya field soil by serial dilution and were identified as Aspergillus flavus Link., A. fumigatus Fresenius, A. niger van Tiegh. and Trichoderma viride Pers. The soil fungi were selected to evaluate their antagonistic potentiality against the three postharvest pathogenic fungi of Carica papaya L. following "dual culture colony interaction” and volatile and non-volatile metabolites. In dual culture colony interaction, out of four soil fungi, T. viride showed the highest growth inhibition on C. gloeosporioides (84.28%), F. nivale (95.23%) and Fusarium sp. (87.15%). On the other hand A. niger showed the highest growth inhibition on C. gloeosporioides (77.39%), F. nivale (98.63%) and Fusarium sp. (35.05%). The maximum inhibition of radial growth of C. gloeosporioides (77.64%), F. nivale (58.76%) and Fusarium sp. (79.37%). were observed in case of T. viride owing to the volatile metabolites. Whereas the maximum inhibition of radial growth of C. gloeosporioides (58.23%), F. nivale (37.43%) and Fusarium sp. (82.31%) were observed in case of A. niger owing to the volatile metabolites. The maximum inhibition of radial growth of C. gloeosporioides (90.90%), F. nivale (89.13%) and Fusarium sp. (76.84%) were observed in case of T. viride owing to the effect of non-volatile metabolites. The maximum inhibition of radial growth of C. gloeosporioides (92.42%), F. nivale (73.01%) and Fusarium sp. (68.67%) were observed in case of A. niger owing to the effect of non-volatile metabolites. Trichoderma viride and A. niger may be exploited commercially as a biocontrol agent against anthracnose and fruit rot pathogens of papaya. Dhaka Univ. J. Biol. Sci. 28(1): 1-7, 2019 (January)

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