• KSBB Journal
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• v.26 no.4
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• pp.357-364
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• 2011

This study was carried out to investigate the effects of agitation, aeration and scale-up on the mycelial growth, exo-polysaccharide (EPS) production, and mycelial morphology in the liquid culture of Ganoderma lucidum. A correlation between roughness and operating variables was also studied to scale-up the liquid culture of G. lucidum in a jar fermenter. When the agitation speed or aeration rate increased, the morphological form was changed from rough pellet to smooth pellet form. Increase of the agitation and aeration reduced the mycelial roughness. On the other hand, in the case of pellet size, it was not affected by aeration. The higher EPS production was obtained at approximately 17% of roughness and mycelial pellet size of 3~5 mm. The morphology at each fermenter was closely correlated with kLa value, and it was found that similarity of morphology would be used as a criteria of scale-up for liquid culture of G. lucidum.

• Journal of Industrial Technology
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• v.21 no.A
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• pp.337-341
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• 2001

This study was carried out to screen the effective polymeric additives preventing wall growth during mycelial submerged cultivation of Ganoderma. lucidum. Effects of additives on mycelial growth and exo-polysaccharide (EPS) production in flask culture and jar fermenter system under 3 different pH processes were investigated, and changes of mycelial morphology were also examined. From flask culture of G. lucidum with additives of different concentrations, 0.1%(w/v) polyacrylic acid was effective for EPS production. As the polyacrylic acid of 0.1%(w/v) was added in medium, wall growth of G. lucidum mycelium grown in jar fermenter system could be protected. The addition of 0.1%(w/v) polyacrylic acid to medium was also improved the mycelial growth and EPS production in the later of submerged culture G. lucidum and no changes of mycelial morphology were observed.

• Microbiology and Biotechnology Letters
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• v.19 no.2
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• pp.193-199
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• 1991

The effects of pH on the cell growth, the elaboration of pullulan, and the morphology of Aureobasidium pullulans IFO 4464 were examined. A. pulluans grew in yeast-like form at constant pH7.5 and in mycelial form at constant pH2.5. At the both pH conditions, the elaboration of pullulan was very low, about 6.0~6.5g/l. The mixture of yeast-like form and mycelial form of cells was found at the constant pH4.5, at which condition, the elaboration of pullulan was high, about 24.5g/l. The pH shift experimemts showed that the specific production rates of pullulan were 0.048($hr^{-1}$)for the mycelial form and 0.058($hr^{-1}$)for the yeast like form, which indicated that the yeast-like form has the similar, only slightly higher, biosynthetic activity of pullulan to the mycelial form at pH4.5 and the pH of culture broth is more important factor for the elaboration of pullulan than the morphology of A. pullulans.

• The Korean Journal of Mycology
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• v.29 no.2
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• pp.91-98
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• 2001

The mycelial morphology during submerged cultivation of Ganoderma ludium using by air-lift fermenter system were analyzed by image processing system and the characterization of mycelial morphology were investigated. In submerged culture using medium with different ammonium phosphate concentrations, the various morphological forms of G. lucidum mycelium were observed. The filamentous forms such as non-branched long filamentous mycelium, non-branched short mycelium, branched long filamentous mycelium, branched short mycelium, entangled mycelium and clump were observed, and also, and also, the pelleted forms such as smooth pellet, rough pellet and hollow rough pellet were observed. The mycelial morphology was changed from the filamentous to the pelleted forms by addition of ammonium phosphate. The fractal dimensions of pelleted and filamentous forms were 1.05 and 1.3, respectively, while the fractal dimension of mixtures of pelleted and filamentous forms was 1.16. Therefore, the fractal dimension was found to be more effective index for the detection of the mycelial morphology and morphological change during batch cultivation. The circularity was also found to be useful for evaluating the surface growth of pelleted mycelium.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.726-731
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• 1999

It was discovered that ammonium phosphate in the medium played an important role in both growing mycelium and producing exopolysaccharides (EPS) from G. lucidum. In lower concentration levels of ammonium phosphate (0-3 g/l), an improved mycelial growth was observed by maintaining more filamentous morphology than in high concentrations (5-11 g/l). In addition, it was confirmed by comparing the factual dimension and frequency of the area regarding the mycelial pellets. This must be attributed to limitations of nutrient transfer by maintaining filamentous mycelium during the cultivation in a low ammonium phosphate containing medium. On the other hand, the best EPS production was observed in medium with the absence or low concentration of ammonium phosphate. The shear stress of the culture broth was greatly affected by the shear rate, as compared with that of the culture broth with high ammonium phosphate concentration. The rheological characteristics of the fermentation broth and filtrate worked well according to the Herschel-Bulkley model. It was also found that the morphological changes of the mycelium resulting from the ammonium phosphate concentration directly affected the rheological characteristics of the system and resulted in reversely affecting the EPS production levels. Based on these results, it can be concluded that delicate regulation of the ammonium phosphate concentration in the culture media should be provided in order to obtain optimal mycelial growth and/or EPS production.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.3
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• pp.161-166
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• 2001

The influence of the consumed carbon to nitrogen (C/N) ratio on mycelial morphology was investigated in cultures of Mortierella alpina using shake flasks. The consumed C/N ratio was varied from 5 to 32 under the condition that the total initial amount of the carbon and nitrogen sources was 50g/L. The whole mycelia and filamentous mycelia exhibited no relationship with the consumed C/N ratio below a consumed C/N ratio of 20 in the presence of either excess carbon or excess nitrogen. However, when the consumed C/N ratio increased higher than 20, the mycelial sizes increased in proportion to the consumed C/N ratio. However, the area ratio of filamentous mycelia to total mycelia was found to be independent of the consumed C/N ratio, and remained constant at 0.82. In the case of a fixed consumed C/N ratio of 20, the whole mycelia and filamentous mycelia increased in proportion to the degree of the medium strength, yet the area ratio of filamentous mycelia to total mycelia remained unchanged at 0.76. Accordingly, these results show that fungal morphology and mycelial size are both affected by the ratio of carbon to nitrogen. The findings of the current study will be helpful in obtaining the efficient production of useful bioproducts from fungal cultures.

• KSBB Journal
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• v.21 no.2
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• pp.103-109
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• 2006

For the study of Hericium erinaceum as a useful functional foods and materials, liquid cultivation under two different bioreactors(air-lift fermenter and jar fermenter) which was not studied systematically until now, was conducted as a method of mass cultivation for H. erinaceum. A batch cultivation in an air-lift fermenter and a jar fermenter was examined for enhancing the productivity because of small amounts of mycelial weight and slow growth in case of a liquid culture for H. erinaceum. We found that air lift fermenter system was more effective than jar fermenter for mycelial production of H. erinaceum, and mycelial morphology was a critical factor of the growth. By scale-up and cultivation based on morphological analysis, the conditions for mass production with 30 L and 500 L jar fermenter was 200 and 150 rpm of agitation speed at 1 vvm of aeration rate, respectively, and mycelial dry weight under these conditions was enhanced to about $13{\sim}14g/L$.

• The Plant Pathology Journal
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• v.32 no.5
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• pp.388-395
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• 2016

The most serious aerial disease of garlic is leaf blight caused by Stemphylium spp. Geographical variation in the causal agent of this disease is indicated. Stemphylium vesicarium has been reported in Spain, whereas S. solani is the most prevalent species recorded in China. In this study, Stemphylium isolates were obtained from symptomatic garlic plants sampled from the main Spanish production areas. Sequence data for the ITS1-5.8S-ITS2 region enabled assignation of the isolates to the Pleospora herbarum complex and clearly distinguished the isolates from S. solani. Conidial morphology of the isolates corresponded to that of S. vesicarium and clearly discriminated them from S. alfalfae and S. herbarum on the basis of the size and septation pattern of mature conidia. Conidial morphology as well as conidial length, width and length:width ratio also allowed the Spanish isolates to be distinguished from S. botryosum and S. herbarum. Control of leaf blight of garlic is not well established. Few studies are available regarding the effectiveness of chemical treatments to reduce Stemphylium spp. incidence on garlic. The effectiveness of nine fungicides of different chemical groups to reduce Stemphylium mycelial growth in vitro was tested. Boscalid + pyraclostrobin (group name, succinate dehydrogenase inhibitors + quinone outside inhibitors), iprodione (dicar-boximide), and prochloraz (demethylation inhibitors) were highly effective at reducing mycelial growth in S. vesicarium with $EC_{50}$ values less than 5 ppm. In general, the effectiveness of the fungicide was enhanced with increasing dosage.

• Journal of Mushroom
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• v.11 no.2
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• pp.63-68
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• 2013

The fruiting body of honey mushroom, Armillaria gallica, was collected from Gastrodia elata cultivated fields. Pure cultures were isolated from fruiting body tissue of the mushrooms, and cultured on MCM (mushroom complete medium) or PDA (potato dextrose agar) medium. Then, 12 different types of mycelial growth characteristics such as growth rate, colony morphology and rhizomorph formation were obtained. The vitality of the mycelial growth and rhizomorph formation of the fruiting body culture isolates were better on MCM than PDA, suggesting that the optimal culture medium for A. gallica mycelia was MCM. To observe the feature of colony morphology, the subculture of isolates were incubated on MCM. Consequently, we could find the segregated or differentiated colony morphology from isolate type 11 that was similar morphology to isolate type 12. For phylogenetic analysis of the 12 isolates, RAPD (Random Amplified Polymorphic DNA) were performed. The isolate type 12 was not only shown different band patterns of RAPD variation in other 11 isolates, but also commercial strain known as Chunmagyun No. 1. Among the tissue culture isolates of fruiting, strains with better mycelial growth characteristics than Chunmagyun No. 1 were selected. We expect that the new strain can be substituted to commercial strain Chunmagyun No. 1.

• Korean Journal of Agricultural Science
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• v.19 no.1
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• pp.33-39
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• 1992

Effects of buprofezin, a chitin synthesis inhibitor of insects, on mycelial growth, protoplast formation and reversion of Coriolus versicolor, Ganoderma applanatum and G. lucidum were investigated. The mycelial growth of C. versicolor, G, applanatum and G, lucidum was severely inhibited by buprofezin treatment, and the inhibition rate severely as the concentration of the buprofezin increased. Aerial mycelia and oidia formation of the mushrooms were increased by buprofezin treatment, but mycelial morphology was not changed. The rate of protoplast formation and reversion of G, applanatum was greatly increased by the treatment of the buprofezin, while that of G. lucidium was decreased. The rate of protoplast formation of C. versicolor was also increased when buprofezin was added to the medium, but the rate of protoplast reversion was not affected by the treatment, From the results obtained in this experiment, we found that the rate of protoplast. formation and reversion was increased by the treatment of the buprofezin in the mushrooms such as C, versicolor and G, applanatum, whose mycelial growth was fast on the medium, while that of G. lucidum, whose mycelial growth was relatively slow, was decreased by the treatment.