• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.206-211
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• 2001

This experiment was conducted to investigate the effects of mixed culture with mycotoxigenic and non-mycotoxigenic fungi on mycotoxin production. For this work, Aspegillus flavus (aflatoxin producing strain), Aspegillus niger (non-mycotoxigenic strain) and Penicillium griseofulvum (patulin producing strain)were cultured in 5 ml SLS medium for 15 days under single or mixed culture. Aflatoxin was determined by direct competitive ELISA, whereas, patulin was measured by HPLC. The mycelial growth, pH and total acidity were also observed by general methods. The mycelial growth was slightly decreased in the mixed culture, meanwhile total acidity was increased and pH was shown lower than that in single culture. Aspergillus flavus produced 145 $\mu\textrm{g}$/ml of aflatoxin for 12 days single culture, but in mixed culture, aflatoxin was decreased to 93%, and was shown as 10.16$\mu\textrm{g}$/ml level. Patulin production in mixed culture was also decreased to 69.3% and was shown only 23.72$\mu\textrm{g}$/ml level as compared with in single culture.

• Applied Biological Chemistry
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• v.24 no.1
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• pp.7-14
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• 1981

Among the Basidiomycetes, Pleurotus ostreatus 301 and Lentinus edodes 3-1 were chosen because of their good enzyme productivity and rapid mycelial growth in rice straw medium. Their cultural conditions adequate for the enzymes production and effects of various materials and inorganic salts added to thd rice straw media were investigated. L. edodes 3-1 was excellent in productivity of cellulase and xylanase, and P. ostreatus 301 in protease. The optimum conditions for enzyme production were at $30^{\circ}C$ in cellulase production and at $25^{\circ}C$ in xylanase and protease production, with 75% moisture content and 5.0-6.0 initial pH. The appropriate cultural periods, for enzyme production were 30 days and 35 days for P. ostreatus 301 and L. edodes 3-1, respectively. Among the various materials added, defatted soybean, defatted rape seed, or defatted sesame were all effective to enzyme production but reduced mycelial growth. Rice bran was also effective, particularly at 30% concentration. The addition of inorganic salts showed effective to enzyme production. Among inorganic salts, optimum concentration of $CaCO_3$ was 5%, and that of $CaSO_4$ was 2%.

• The Korean Journal of Mycology
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• v.34 no.1
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• pp.1-6
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• 2006

In order to select a suitable bioreactor type for the submerged cultivation of Ganoderma applanatum, both growth characteristics and polysaccharides production were compared among four different types of bioreactor. These include an external-loop type air-lift bioreactor (ETAB), a balloon type air bubble bioreactor (BTBB), a column type air bubble bioreactor (CTBB) and a stirrer type bioreactor (STB). The mycelial biomass produced from the reactors were in decreasing order: ETAB ($7\;g/{\ell}$) > BTBB ($6.2\;g/{\ell}$) > STB ($6\;g/{\ell}$) > CTBB ($5\;g/{\ell}$). Maximal soluble exopolysaccharides ($1\;g/{\ell}$) and endopolysaccharides (2.7%) were also obtained from ETAB. Thus, the ETAB was most suitable for submerged culture of G applanatum mycelium. Based on the results, ETAB was chosen for further detailed study. The most effective aeration rate for the mycelial growth in ETAB ranged from 0.05 to 0.1 vvm. For the maximal production, the mycelium at the initial growth stage needed low aeration rate to reduce cell damages by fluid flow. However, as the mycelia grew, the culture became viscous and thus needed higher aeration. The molecular weight of exopolysaccharides obtained from the culture grown in ETAB was higher than that from the culture grown in other bioreactors.

• The Korean Journal of Mycology
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• v.33 no.1
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• pp.11-17
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• 2005

To increase the fibrinolytic activity and production of mycelium, extracts of 7 plant species were supplemented to the growth media of Armillaria mellea, and mycelial growth and enzymatic activity in the mycelium extracts of A. mellea were estimated. The mycelial production of A. mellea was slightly increased by adding ASH-R, UDVN or RGR extract, whereas KG extract significantly affected the growth. Supplement of ASH-S, UDVN and RGR extracts increased proteolytic activity from 36.8 to 46.1% Fibrinolytic activity was increased to $50{\sim}65%$ by supplement with RVS, ASH-S and RGR extracts, respectively. Enzyme extracts of the fungus grown with RGR extract supplement degraded all chains of fibrinogen within 2 hours, whereas control was required 3 hours. Degradation of fibrin fragments by the enzyme extracts was also observed through microscopy.

• Korean Journal of Microbiology
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• v.26 no.2
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• pp.143-147
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• 1988

The effect of ginseng saponin on aflatoxin(AF) production by Aspergillus parasiticus NRRL2999 and the mutagenicity of produced aflatoxin. The production of aflatoxin were decreased by the addition of ginseng saponin and the most effective concentration was 0.05%. The ratio of aflatoxin $B_{1}$ and aflatoxin $G_{1}$ were not changed by the addition of ginseng saponin. For the nutagenicity test, Ames method were adopted. Mutagenicity of mycelial aflatoxin was decreased by the addition of ginseng saponin on TA98, but not changed on TA100. Mutagenicity of excreted aflatoxin to broth was slightly increased by the saponin on TA98, but decreased on TA100.

• Journal of Industrial Technology
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• v.8
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• pp.13-21
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• 1988

For the improvement of productivity of Pleurotus ostreatus, the production of liquid spawn was studied. The highest liquid spawn production was obtained after shaking culture for 4 days in the culture medium containing 5%(W/V) wheat flour, 0.2%(W/V) yeast extract, 0.1%(W/V)$KNO_3$ 0.05% (W/V) $MgSO_4{\cdot}7H_2O$, 0.05%(W/V) $KH_2PO_4$. The optimum pH and temperature was 7.0 ana $30^{\circ}C$. The period required to complete the mycelial growth after spawning were 28, 22, 10 and 9 days, respectively, when the 2%(V/V) of solid spawn and 2%(V/V), 5% (V/V) and 10%(V/V) of liquid spawn were inoculated. The days required from spawning to fruiting bodies were 38, 34, 28 and 27 days.

• Korean Journal of Microbiology
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• v.21 no.4
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• pp.213-220
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• 1983

Conditions for isolation of protoplasts from conidiospores of Trichoderma koningii ATCC 26113 were tested. Maximum production of conidial protoplasts was obtained by preincubation of conidiospores on liquid minimal medium for 8 1/2 hrs. and by reaction with cell wall lytic enzyme for 3 hrs. Among effective cell wall lytic enzymes (Driselase, p-Glucuronidase, Novozyme and Zymolyase), Driselase was the most effective one on the production of conidial protoplasts. The production of conidial protoplasts was also enhanced by addition of 2-Deoxy-D-Glucose $(25{\mu}g/ml)$ into liquid minimal medium. Over 70% of the initial swollen conidia, preincubated in liquid minimal medium supplemented with 2-Deoxy-D-Glucose $(25{\mu}g/ml)$, were converted to protoplasts by incubation with 2% (w/v) commercial lytic enzyme Driselase at $28^{\circ}C$ for 3 hrs. The reversion frequency of the conidial protoplasts was about 30 times (25-50%) higher than that of mycelial protoplasts (0.6-1.3%).

• KSBB Journal
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• v.13 no.4
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• pp.364-368
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• 1998

The optimum conditions of the production of exo-polymer by Ganoderma lucidum WK-003 and it's hepatoprotective effect was studied. Optimum conditions for the production of exo-polymer (3.18 g/$\ell$) by using shaken flask culture of G. lucidum WK-003 were pH 4.5, 30$^{\circ}C$, 120 rpm for 18 days cultivation. Also exo-polymer productio (7.15 g/$\ell$) was optimized by 5$\ell$ jar fermenter cultivation with condition of pH 4.5, 30$^{\circ}C$, 200 rpm, 1.0 vvm for 6 days cultivation. Glutamic pyruvic transaminase(GPT) activities in serum of intoxicated Sprague-Dawley rat were decreased from 704 IU/L to 330 IU/L by oral administration of the exo-polymer (20mg/kg$.$day)f or 4 consecutive days.

• Mycobiology
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• v.36 no.3
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• pp.167-172
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• 2008

Beef luncheon meat is one of the most popular meals in several countries in the world including Egypt. Thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in Qena. Alternaria, Aspergillus, Emericella, Mucor, Mycosphaerella, Penicillium and Rhizopus were the most common genera on the two types of media. From the above genera, the most prevalent species were Alternaria alternate, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emericella nidulans, Mucor racemosus, Mycosphaerella tassiana, Penicillium chrysogenum and Rhizopus stolonifer. Screening of fungi for their abilities to produce lipase enzyme showed that, ten isolates represented 32.26% of total isolates appeared high lipase production, while sixteen isolates (51.61%) were moderate and 5 isolates (16.13%) were low producers. Aspergillus niger, Fusarium oxysporum and Nectria haematococca produced the highest amount of lipase enzyme, so these fungi were used in further studies. The incorporation of five food preservatives (Disodium phosphate, sodium benzoate, citric acid, potassium sorbate and sodium citrate) individually in the culture medium of lipase production exhibited an inhibitive effect on the mycelial growth and enzyme production by Aspergillus niger, Fusarium oxysporum and Nectria haematococca.

• Journal of Mushroom
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• v.2 no.2
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• pp.69-75
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• 2004

This study was carried out to investigate effect of $CaCO_3$ treatment on cultivation of oyster mushroom for suppression of green mold disease and for promotion of mycelial growth to stabilize mushroom production in field and laboratory experiment. Treatment of $CaCO_3$ in PDA media promoted mycelial growth of mushroom and suppressed that of green mold. Addition of $CaCO_3$ in rice straw substrate increased mushroom mycelial growth compared with control. In that case, growth of green mold increased up to treated 0.6% $CaCO_3$ but decreased in treatment beyond 0.8% $CaCO_3$. There were some differences on effect of $CaCO_3$ treatment according to green mold species. Trichoderma longibrachiatum was effected but T. virens was not effected by treated $CaCO_3$. Differences among mushroom strains by treated $CaCO_3$ were not shown. It is confirmed that treatment of $CaCO_3$ can promote mushroom mycelial growth but it's not clear in the field. In the result of field test, treatment of $CaCO_3$ in rice straw substrates tended to increase yield and decrease incidence of disease compared with non-treatment. These results suggest that $CaCO_3$ treatment on cultivation of oyster mushroom can be applied to take preventive steps against of green mold disease.