• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.482-487
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• 2000

Optimization of submerged culture conditions for the production of exo-biopolymer from Paecilomyces japonica ws studied. Maltose, yeast extract, and potassium phosphate were the most suitable sources of carbon, nitrogen, and inorganic salt, respectively, for both production of the exo-biopolymer and mycelial growth. The optimal culture conditions in a flask culture were pH 5.0, $25^{\circ}C$, and 150 rpm in a medium containing (as in g/l) 30 maltose, 6 yeast extruct, 2 polypeptone, $0.5{\;}K_3HPO_4,{\;}0.2{\;}KH_2PO_4,{\;}0.2{\;}MnSO_4{\cdot}5H_2O,{\;}0.2{\;}MgSO_4{\cdot}7H_2O$. Exo-biopolymer production and mycelial growth in the above suggested medium were significantly increased in a 2.5-1 jar fermentor, where the maximum biopolymer concentration was 8 g/l. The morphological changes of the mycelium in the submerged culture were observed within pH ranges from 4.0 to 9.0; i.e., growth of the filamentous form was optimal at culture pHs of 5.0 and 6.0, whereas pellet was formed at other pHs.

• 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.

• Mycobiology
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• v.35 no.3
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• pp.145-149
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• 2007

The Elfvingia applanata (EA), Hericium erinaceum (HE), Grifola frondosa (GF), Pholiota nameko (PN), Pleurotus eryngii (PE), Trametes suaveolens (TS), Fomes fomentarius (FF), and Inonotus obliquus (IO) could produce the endo- (EN) and exo-biopolymer (EX) in submerged culture. The highest anti-complementary activity of the EN was exhibited by PN (49.1%), followed by HE (38.6%), TS (37.0%), and FF (33.0%), whereas the high activity of the EX was found with GF (59.8%), followed by HE (36.3%), TS (30.8%), and IO (28.8%). The EN of P. nameko (EN-PN) and EX of G. frondosa (EX-GF) were found to contain 78.6% and 41.2% carbohydrates, while 21.4% and 58.8% protein, respectively. The sugar and amino acid compositions of EN-PN and EX-GF were also analyzed in detail.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.972-977
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• 2004

The hypoglycemic effect of an exo-biopolymer (EXO) and endo-biopolymer (ENDO) produced from submerged mycelial culture of Ganoderma lucidum was investigated in streptozotocin (STZ)-induced diabetic rats. Both the EXO and ENDO showed hypoglycemic potential, however, the former proved to be more potent than the latter. The administration of the EXO at the dose of 100 mg/kg body weight (BW) significantly reduced the plasma glucose level (23.5%) and increased the plasma insulin level (2.2 fold) in the diabetic animals. The EXO also lowered the plasma total cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, and athrogenic index by 14.7, 31.4, 24.1, and 45.4%, respectively, and reduced the liver total cholesterol and triglyceride levels by 6.7 and 25.8%, respectively. It increased the plasma high-density lipoprotein (HDL) cholesterol (37.7%), compared to the control group. Furthermore, the alanine transaminase (ALT) and aspartate transaminase (AST) showed lower activities in the EXO administered groups than the other experimental groups. Taken together, these results suggest that the exo-biopolymer may alleviate the blood glucose level by increased insulin secretion.

• 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.

• 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 Microbiology and Biotechnology
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• v.8 no.5
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• pp.536-539
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• 1998

The anti-complementary activity (immuno-stimulating activity) was tested for the exo-polymers (extra-cellular polymer) produced from submerged mycelial cultures of 21 types of higher fungi. Anti-complementary activity of the exo-polymer from Cordyceps militaris showed the highest (69.0%) followed by Pleurotus ostreatus (63.7%) and Trametes suaveolens (61.4%). The mycelial growth rate and biomass doubling time of C. militaris in a 5 I air-lift fermenter were 0.0255 $h^{-1}$ and 27.2 h, respectively. The yield of the exo-polymer produced from the culture broth of C. militaris was 2.95 mg of dry weight/ml of culture broth. Sugar and amino acid compositions of this exo-polymer were analyzed.

• 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.42 no.1
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• pp.64-67
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• 2004

The pellets from a culture of Streptomyces coelicolor A3(2) that were submerged shaken were disintegrated into numerous hyphal fragments by DNase treatment. The pellets were increasingly dispersed by hyaluronidase treatment, and mycelial fragments were easily detached from the pellets. The submerged mycelium grew by forming complexes with calcium phosphate precipitates or kaolin, a soil particle. Therefore, the pellet formation of Streptomyces coelicolor A3(2) can be considered a biofilm formation, including the participation of adhesive extracellular polymers and the insoluble substrates.

• The Korean Journal of Mycology
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• v.35 no.1
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• pp.37-42
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• 2007

The mushroom Lentinus lepideus was used to produce mycelial as well as soluble polysaccharides in bioreactor cultures. To determine optimal submerged culture conditions, both growth characteristics and water soluble polysaccharides production were compared among four different types of bioreactor and culture conditions. For the production of mycelial biomass, the following bioreactors were proven to be effective in decreasing order: an external-loop type air-lift bioreactor (ETAB; 7g/l), a balloon type air bubble bioreactor (BTBB; 6.2g/l), a stirrer type bioreactor (STB; 6g/l), and a column type air bubble bioreactor (CTBB; 5g/l). Maxiaml production of water soluble exopolysaccharides (EPS; 0.62g/l) and endopolysaccharides (PPS; 7.7%) could also be obtained from BTBB. The mycelial biomass increased with increase in glucose concentration from 15g/l to 75g/l in the media. In contrast, PPS contents in the cells decreased with increase in glucose concentration in the media, showing the highest PPS content (7%) at 15g/l. Among different medium feeding types, fed-batch culture based on concentration control in media (10g/l) produced higher mycelia than fed-batch culture based on volume control of media (5.8g/l) or batch culture (3.4g/l). EPS production was also higher in fed-batch culture based on medium concentration control than that in other feeding types.