• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.944-951
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• 2004

The influences of inoculum size, pH, and medium composition on mycelial growth and exopolysaccharides (EPS) production were investigated in shake flasks and in a bioreactor. The optimum inoculum size for both mycelial growth and EPS production was identified to be 10% (v/v) in shake flask cultures. The optimal initial pH for mycelial growth and EPS production in shake flask cultures were found to be 5.0 and 7.0, respectively. However, the optimal pH was 5.0 for both mycelial growth and EPS production in bioreactor cultures where the pH was regulated. The optimal mass ratio of the two major carbon sources, glucose to dextrin, was 1:4. The optimal mass ratio of the two major nitrogen sources, yeast extract to soy tone peptone, was 2:1. When 500 mg $1^{-1}$ of $MnSO_4-5H_2O$ was added to the bioreactor culture, both mycelial growth and EPS production were enhanced by approximately 10%. Under the optimized conditions, a mycelial biomass of 9.85 g $1^{-1}$ and an EPS concentration of 4.92 g $1^{-1}$ were obtained in 4 days.

• The Korean Journal of Mycology
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• v.30 no.1
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• pp.1-5
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• 2002

Cultural characteristics of Cordyceps militaris preserved in EFCC, Kangwon National University were investigated for the mass production. The higher mycelial density of C. militaris was observed in Sabouraud's yeast and Yeast Malt agars, but the higher mycelial growth in Mushroom Minimal agar than other agars. The mycelium of C. militaris was observed to grow well at $25^{\circ}C$ and pH 6.0 respectively. The dextrose was found the best suitable energy source among the carbohydrates used for its mycelial growth, while the fructose or lactose observed to be well for mycelial growth. Hemoglobin was observed to be the best among the protein sources used for mycelial growth, while tryptone found to be the best in the spore formation. Similarly, the mycelial growth was best in mineral salts of $KH_2PO_4$ or $K_2HPO_4$ and the optimum C/N ratio was 100 : 1.

• Plant Resources
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• v.3 no.2
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• pp.110-117
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• 2000

The recycling method of enokitake cultural waste and the potentiality of second flush for enokitake were determined, because this fungus is not as prolific as the more commonly cultivated white rot fungi in the conversion of sawdust to mycelial mass. The mycelial growth of F. velutipes on several substrates, variously treated with rice bran was promoted at ratios of 10-20% (w/w) on all substrates, but suppressed at above ratios, although some difference was there. The mycelial densities generally increased correlated to the supplementation contents of rice bran. It could be concluded that F. velutipes preferred mild acidic to acidic conditions for mycelial growth, considering that the mycelial growth rate was highest on waste of pH 6.01, treated with 0.1 % Ca(OH)$_2$ and on populus mixed waste of pH 6.02, non treated. The ranges of substrate bulk densities, which was pertinent for mycelial linear growth were from B.D. (g/cc) 0.17 to 0.23 on waste and populus mixed waste all. The pertinent contents of rice bran supplementation in bottle cultivation was from 20 to 30% on waste and 20% on populus mixed waste, considering the requried duration for pinheading and fruiting yields. Standard bulk density for filling and utilizing the waste and populus mixed waste for commercial f. velutipes cultivation were B.D.(g/cc) 0.19 ~ 0.23, and 0.23~ 0.25, which could be conversed to 510~ 540g/900m1 and 520~ 570g/900m1, respectively, The second flush of F. velutipes was tried and the re-inoculation by sawdust and liquid spawn showed somewhat good results, indicating the potentiality of second crop and suggesting further research for it.

• 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 Korean Journal of Mycology
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• v.37 no.2
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• pp.167-172
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• 2009

Mycelia of Pleurotus ostreatus, Phellinus linteus, Ganoderma lucidum and Lentinus edodes were cultured in the selected cereals to generate functionally active cereals. The optimum water contents for the mycelial growth were 50%(wt/wt) for brown rice, barley and soybean and 75% for wheat and corn, respectively. P. ostreatus grew well in the most cereals while the mycelial growth of P. linteus, G. lucidum and L. edodes in soybean were siginificantly retarded. The contents of β-glucan and glucosamine in the mycelial cereals were determined. Wheat cultured with mushroom mycelia showed high ß-glucan content. Especially, wheat with G. lucidum contained the highest value of 26.16%. Soybean cultured with G. lucidum showed two-fold increase in glucosamine content with 9.63% of total mass while wheat showed 7.91%. Overall, wheat cultured with G. lucidum was the best functional cereal in terms of β-glucan and glucosamine contents.

• Mycobiology
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• v.35 no.2
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• pp.54-61
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• 2007

Two isolates of Tricholoma matsutake T-008 and T-034, preserved in Entomopathogenic Fungal Culture Collection (EFCC) of Korea, were used in the present study. The isolates had 100% Bootstrap homology with Tricholoma matsutake U62964 and T. matsutake AB188557 and AF309538 preserved in Gene Bank of NCBI. Mycelial growth of T. matsutake was highest in TMM and MYA at $25^{\circ}C$. The highest dry wt. of mycelium was obtained after 65 days of culture, when 6 mycelial discs were inoculated in 100 ml of broth in 250 ml shaking flask. Mycelial mats were observed in clumped condition at the inoculation sites of pine forest after two weeks of inoculation. After 5 months of inoculation, mycelia mats were observed growing inside soil and walls of a few inoculation sites, while mycelial mats growth up to $5{\sim}8$ cm were observed in the roots of pine tree after 6 months. The survival rate of the inoculum was about 40% of the total inoculation sites. The survival rate was found below 20% when the mycelium was inoculated in the summer. The reasons for low survival rates of the mycelium were mainly due to dry season and the soil-borne small animals such as earthworm and mole. After one year of inoculation, no external difference was observed between the artificially inoculated mycelia and the naturally existing mycelia of T. matsutake. The present study showed that fruiting bodies of T. matsutake could be produced by artificial inoculation under the appropriate environmental conditions.

• Journal of Mushroom
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• v.2 no.4
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• pp.192-199
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• 2004

The mycelial mass of K. mutabilis greatly increased at pH 5.5~6.0 but decreased pH 6.0. The linear mycelial growth wsa mostly supported on sawdust of Quercus accutisima and the mycelial density wsa high on sawdust of Q. accutisima and corn cob. Much mycelial distribution could be showen in ray parenchyma cell and ray tracheid. Severe degradation of ray parenchyma cell was found but little degradation of ray tracheid cell was found. The dry weight loss wsa 5.9% after agar-block test. And the pH wsa acidified from 6.07 to 4.31 and hot water extractives was decreased after degradation of Q. serrata sawdust by K. mutabilis.

• Mycobiology
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• v.32 no.1
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• pp.1-5
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• 2004

The present study was carried out to investigate morphological characteristics of pseudosclerotia of Grifola umbellata formed by artificial cultures. Isolate G. umbellata DUM GUS-01 was obtained from sclerotium cultivated in field. The fungal isolate was cultured on PDYM broth, PDYMA(potato dextrose yeast malt agar) and oak sawdust media at $20^{\circ}C$ under the dark condition. G. umbellata DUM GUS-01 showed a volumetric increment of fungal lumps rather than mycelial growth. Particularly, G. umbellata DUM GUS-01 produced a large amount of melanin pigments in all culture treatments. The color of the fungal mass has been changed into grey gradually, and then formed melanized rind-like structure on its superficial part. The fungal structures which were covered with melanized rind-like layer were named as pseudosclerotia of G. umbellata. The pseudosclerotia of G. umbellata DUM GUS-01 formed a new white mycelial mass, which was swollen out of the melanized rind structure for its volumetric increment. When the pseudosclerotia were sectioned, their structure was discriminated from two structures such as a melanized rind-like structure layer formed by aggregation of aged mycelia and a white mycelial mass with high density. As results of scanning electron microscopic examination, the pseudosclerotia of G. umbellata DUM GUS-01 which were formed in in vitro conditions were similar to the sclerotia of G. umbellata cultivated in natural conditions except for the crystals formed in medula layer of natural sclerotia. Although size, solidity of rind structure and mycelial compactness of pseudosclerotia were more poor than those of natural sclerotia, the morphological structure and growth pattern of pseudosclerotia were very similar to those of natural sclerotia. Therefore, it is probable to induce pseudosclerotia to sclerotia of G. umbellata in in vitro conditions. Consequently, it seems that the induced pseudosclerotia can be used as inoculum sources to substitute natural sclerotia in field cultivation.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.355-358
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• 2001

Selection of optima] nutrient sources and cultural methods for liquid spawn culture of Flammulina velutipes were carried out. The optimal temperature and pH for mycelial growth of F. velutipes were $20^{\circ}C$ and 6.0 to 7.5. respectively. In the 250ml ${Delta}$-flask culture. the amount of inoculum and culture period for the optimal mycelial growth of F. velutipes were 3 mycelial disks(diametcr 6mm) and 6 days, respectively. For the mass production of submerged culture. the optimal inoculum amount and aeration rate of F. velutipes were 5%(inoculum vol/medium vol.) and l.0vvm(vol of air/vol. of medium/min), respectively.

• The Plant Pathology Journal
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• v.23 no.2
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• pp.97-102
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• 2007

A total of 39 essential oils were tested for antifungal activities as volatile compounds against five phytopathogenic fungi at a dose of 1 ${\mu}l$ per plate. Five essential oils showed inhibitory activities against mycelial growth of at least one phytopathogenic fungus. Origanum vulgare essential oil inhibited mycelial growth of all of the five fungi tested. Both Cuminum cyminum and Eucalyptus citriodora oils displayed in vitro antifungal activities against four phytopathogenic fungi except for Colletotrichum gloeosporioides. The essential oil of Thymus vulgaris suppressed the mycelial growth of C. gloeosporioides, Fusarium oxysporum and Rhizoctonia solani and that of Cymbopogon citratus was active to only F. oxysporum. The chemical compositions of the five active essential oils were determined by gas chromatography-mass spectrometry. This study suggests that both E. citriodora and C. cyminum oils have a potential as antifungal preservatives for the control of storage diseases of various crops.