• Mycobiology
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• v.37 no.2
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• pp.89-93
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• 2009

The effect of fermentation parameters and medium composition on the simultaneous mycelial growth and exo-polymer production from submerged cultures of Ganoderma applanatum was investigated in shake-flask cultures. The optimum initial pH for mycelial growth and exo-polymer production was 5.0 and 6.0, respectively. The optimum temperature was $25^{\circ}C$ and the optimum inoculum content was 3.0% (v/v). The optimal carbon and nitrogen sources were glucose and corn steep powder, respectively. After 12 days fermentation under these conditions, the highest mycelial growth was 18.0 g/l and the highest exo-polymer production was 3.9 g/l.

• 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.

• Mycobiology
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• v.31 no.4
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• pp.205-208
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• 2003

The production of polysaccharide according to various developmental stages(mycelium growth, primordium appearance, and fruiting-body formation) in the edible mushroom Grifola frondosa was studied. The cap of the mature mushroom showed the highest amount of polysacchride. Mycelial growth and polysaccharide synthesis were optimal at pH 5 and $20^{\circ}C$. Polysaccharide synthesis was maximal after 12 days of cultivation, whereas maximum mycelial growth was shown after 18 days. Mannose, cellobiose and starch increased the level of polysaccharide as well as growth in submerged culture. Glucose and sucrose appeared to be good substrates for fruiting of Grifola frondosa.

• Journal of Life Science
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• v.14 no.1
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• pp.51-56
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• 2004

The polysaccharide isolated from Phellinus species has been known as a folk remedy, including antitumor and immune-stimulating activities. However, there are lacks of knowledge about mycelial growth and exopolysaccharide (EH) production in its submerged culture. We investigated the optimal conditions on mycelial growth and EPS production in Phellinus baumii. The optimal temperature and initial pH for mycelial growth and EPS production in shake flask culture of P. baumii were proved to be 3$0^{\circ}C$ and pH 5.0, respectively. In case of carbon source, cellobiose and maltose were highly efficient for mycelial growth and fructose and mannitol were also relatively favorable for EPS production. Yeast extract was the most suitable nitrogen source for mycelial growth and EPS production. The composition of optimal culture medium was determined to be fructose 20 g/L, yeast extract 20 g/L, and $CaCl_2$ 0.55 g/L, respectively. Under the optimal culture condition, the maximum mycelial biomass and EPS achieved in a 5-L stirred-tank fermenter were 17.43 g/L and 3.6 g/L, respectively. It was found that the EPS was a glycoprotein onsisted of mainly arginine (14.1%) and glycine (12.0 %) in protein moiety and mainly mannose (48.7%) and arabinose (38.4%) in carbohydrate moiety.

• Journal of Microbiology
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• v.44 no.2
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• pp.233-242
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• 2006

The objectives of this study were to optimize submerged culture conditions of a new fungal isolate, Ganorderma resinaceum, and to enhance the production of bioactive mycelial biomass and exopolysaccharides (EPS) by fed-batch culture. The maximum mycelial growth and EPS production in batch culture were achieved in a medium containing 10 g/l glucose, 8 g/l soy peptone, and 5 mM $MnCl_2$ at an initial pH 6.0 and temperature $31^{\circ}C$. After optimization of culture medium and environmental conditions in batch cultures, a fed-batch culture strategy was employed to enhance production of mycelial biomass and EPS. Five different EPS with molecular weights ranging from 53,000 to 5,257,000 g/mole were obtained from either top or bottom fractions of ethanol precipitate of culture filtrate. A fed-batch culture of G. resinaceum led to enhanced production of both mycelial biomass and EPS. The maximum concentrations of mycelial biomass (42.2 g/l) and EPS (4.6 g/l) were obtained when 50 g/l of glucose was fed at day 6 into an initial 10 g/l of glucose medium. It may be worth attempting with other mushroom fermentation processes for enhanced production of mushroom polysaccharides, particularly those with industrial potential.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.477-483
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• 1999

For Trametes sp. CJ-105, a kind of white-rot fungi which was collected from the mountain of Korea and was proven to be effective in decolorizing a wide range of structurally different synthetic dyes, the optimum conditions for mycelial growth and laccase(E.C. 1.10.3.2) production were investigated. Among various carbon sources, glucose showed the highest potential for the mycelial growth and laccase production, the optimum concentration being 2% glucose. For the nitrogen source, asparagine was good for the mycelial growth, while ammonium tartrate for laccase production(optimum concentration: 0.04%). The addition of thiamine and biotin increased both th emycelial growth and laccase production. When 2,5-xylidine was added as an inducer after the first day of culture, the production of alccase was seven-times higher than that in the absence of the inducer. The optimum pH and temperature conditions for laccase production by Trametes sp. CJ-105 were pH 5.0 and $25^{\circ}C$, respectively. In the 5L fermentation, the production of laccase reached a maximum of 340U/ml at the time when the ammonium ion was being rapidly depleted.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.29-29
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• 2018

Sparassis latifolia is called "Cauliflower Mushroom" and is known as an edible mushroom that has high content of ${\beta}$-glucan. Recently, artificial cultivation of S. latifolia has been done by bottle, plastic bag and wood cultivation in Korea. However it is not widely used because there are low incubation ratio and yield. For the high efficiency of production, we aim to find the superior strains and media for better mycelial and fruit body growth. First, we analyzed the genetic relationship among 31 strains and divided five groups with three kinds of URP primers. And then ten strains were selected from five groups based on the experiment of mycelial growth. The suitability of media for mycelial growth was different according to media type. The suitable solid and liquid media for mycelial growth of S. latifolia isolates were PDA and M2, respectively. In addition, with regard to C/N ratio, the mycelial growth increased even until C/N 160. Second, we investigated the production of fruitbody of the strains by plastic bag cultivation. The substrate was mixed with larch sawdust, corn flour, and wheat flour (8:1:1, v/v). Moisture content of substrate was controlled by about 60% with 10% molasses solution. Out of 31 strains, 19 strains formed primordia. The eight strains produced more than 140g/1kg in fresh weight. Third, molasses culture media was selected for the mycelial growth. And molasses suitable sugar content and input aeration were around 8Brix% and 0.3~0.6vvm, respectively. The longer the incubation period is, the more dried weight of mycelia increased, but medium volume decreased. Therefore, the best incubation period was 9 to 11 days depending on strains. In the future, research project entitled development of culture system and new variety for stable production of S. latifolia will be considered as a new item.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.219-232
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• 2019

Chemicals related to hydrogen peroxide ($H_2O_2$) and nitric oxide (NO) generations were exogenously applied to Fusarium oxysporum f. sp. fragariae (Fof) causing Fusarium wilt disease in strawberry plants, and regulations of in vitro conidial germination and mycelial growth of the fungus by the chemical treatments were evaluated. $H_2O_2$ drastically reduced the conidial germination of Fof in a dose-dependent manner, and treatment with 3-amino-1,2,4-triazole (3-AT) catalase inhibitor also led to dose-dependent inhibition of conidial germination but relatively moderately. Gradual decreases in mycelial growth of Fof were found by high concentrations of $H_2O_2$, whilst exogenous 3-AT slightly increased the mycelial growth. Increasing sodium nitroprusside (SNP) NO donor, $N^G$-nitro-l-arginine methyl ester (L-NAME) NO synthase (NOS)-inhibitor and tungstate nitrate reductase (NR) inhibitor led to dose-dependent reductions in conidial germination of Fof in quite different levels. SNP conversely increased the mycelial growth but increasing L-NAME moderately decreased the mycelial growth. Tungstate strongly enhanced mycelial growth. Differentially regulated in vitro mycelial growths of Fof were demonstrated by SNP, L-NAME and tungstate with or without $H_2O_2$ supplement. Superoxide anion production was also regulated during the mycelial growth of Fof by nitric oxide. These results show that $H_2O_2$ and NO-associated enzymes can be suggested as fungal growth regulators of Fof as well as eco-friendly disease-managing agents in strawberry production fields.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.560-567
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• 2008

An efficient method to produce water-soluble polysaccharides from Lentinus lepideus is described. The productivity of both endopolysaccharides (PPS) and exopolysaccharides (EPS) was compared under various culture conditions. The effect of treating their own PPS and EPS on immune cytokine production was also studied in relation to culture factors. High yield production of EPS required a moderate culture temperature $(25^{\circ}C)$ as well as long culture period (16-20 days). In contrast, PPS production required a high culture temperature $(30^{\circ}C)$ and short culture period (8 days). Most of the carbon sources did not affect polysaccharides and mycelial production except for sucrose. Immune cytokine levels in the EPS treatment varied among carbon sources or culture periods. PPS did not appear to affect much on the production of cytokines, regardless of the culturing factors, except for the culture period. These results suggest that the optimal culture conditions for L. lepideus vary according to culture purposes, and different culture conditions should be used for different targets including mycelial biomass, EPS, and PPS. Whereas the immunomodulating activitiy of EPS appeared to be affected by culture conditions in L. lepideus, that of PPS did not.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.200-204
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• 1997

The effect of water potential ($\psi_W$) and temperature on mycelial growth and sclerotial production of Sclerotium cepivorum was determined in potato dextrose agar(PDA) and potato dextrose broth (PDB) adjusted to different $\psi_W$ with NaCI, KCI, sucrose or polyethylene glycol (PEG) at 15, 20 and $25^{\circ}C$. the growth of mycellium was not significantly af. fected by $\psi_W$ values between -1,970 and -2,240J/Kg, but severely decreased lower than -2,240J/Kg. Dry weight was slightly increased at $\psi_W$values between -450 and -2,240 J/Kg. The reduction of dry weight wasslower than the reduction of mycelial growth as the $\psi_W$ decreased. The mycelial growth and dry weight were more severely influenced on PEG amended media than on other osmotica amended media. About 50% reduction of mycelial growth and dry weight was occurred about -1,000 and -2240 J/Kg, respectively. The production of sclerotion of sclerotial production occurred between -450 and -810 J/Kg. Sclerotium was not produced lower than -2,240 J/Kg. Mycelial growth and sclerotial production was better at $25^{\circ}C$ as the $\psi_W$ decreased than at $20^{\circ}C$ which is optimal temperaturein the undmended media. The influence of $\psi_W$ on mycelial growth and sclerotial production of S. cepivorum adjusted with NaCl, KCI sucrose or polyethylene glycol showed similar patterns.