• Mycobiology
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• v.30 no.3
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• pp.166-169
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• 2002

Protein productivity by the cellulolytic fungi, Trichoderma viride(MTCC 800), Chaetomium globosum and Aspergillus terreus was compared in co-culture and mixed culture fermentations of cashewnut bran. Co-cultures were more effective in substrate saccharification, which ranged between $85{\sim}88%$ compared to the $62{\sim}67%$ saccharification shown by the monocultures. Maximum saccharification was induced by T. viride and C. globosum co-culture resulting in the highest 34% release of reducing sugars. The maximum 16.4% biomass protein and the highest protein productivity(0.58%) were shown by T. viride and A. terreus co-culture. A. terreus performed better in co-culture in the presence of T. viride rather than with C. globosum. Among the cellulolytic enzymes, FPase(Filter Paper Cellulase) activity was significantly higher in all the co-cultures and in the mixed culture than in their respective monocultures. Mixed culture fermentation involving all the three fungi was not effective in increasing the per cent saccharification or the biomass protein content over the co-cultures.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1120-1123
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• 2001

Screening tests against six plant pathogenic fungi were performed in order to develop biopesticides. Actinomycetes were used to discriminate Bacillus thuringiensis for wide use as a microbial pesticide. From more than 100 actinomycetes tested, twelve strains showed potent antifungal activities. We report in vivo screening results from fermentation broths of these twelve strains and identification of the strain taxa.

• Natural Product Sciences
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• v.5 no.3
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• pp.151-153
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• 1999

(+)-Hernandulcin is a sweet bisabolane-type sesquiterpene first isolated from Lippia dulcis Trev. (Verbenaceae). This oily compound is 1000-1500 times sweeter than sucrose but with poor solubility in water. Microbial transformation was employed to improve its water solubility, and a variety of microorganisms were screened for their ability to convert (+)-hernandulcin to more polar metabolites. Scale-up fermentation with Glomerella cinguiata, a fungal strain, has resulted in the isolation of a more polar metabolite (2).

• Archives of Pharmacal Research
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• v.8 no.2
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• pp.67-75
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• 1985

To find emylase inhibitors produced by microorganisms from soil, a strain which had a strong inhibitory activity against bacteria .alpha.-amylase was isolated from the soil smaple collected in Seoul. The morphological and physiological characteristics of this strain on several media and its utilization of carbon sources showed that it was one of Streptomyces specties according to the international Streptomyces Project method. The amylase inhibitor of this strain was purified by means of acetone precipitation, adsorption on Amberlite XAD-2, and column chromatography on Amberlite CG-50 and SP-Sephadex C-25. The inhibitor was stable at the pH range of 1-10 and at 100.deg.C for half an hour, and had inhibitory activities against other amylases such as salivary .alpha.-amylase, pancreatic .alpha.-amylase, fungal .alpha.-amylase and glucoamylase. The kinetic studies of the inhibitor showed that its inhibitory effect on starch hydrolysis by .alpha.-amylase was non-competitive.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.208-213
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• 2007

The objective of the experiment was to determine the optimum cultural [moisture levels (55, 60 and 70%), days of fermentation (7, 14 and 21), temperature (25 and $35^{\circ}C$) of incubation)] and nutritional parameters (urea addition (0 and 2%) and variable levels of single super phosphate (0.25 and 0.50% SSP)) for bio-processing of the mustard (Brassica campestris) straw (MS) under solid-state fermentation (SSF) system. The performance of SSF was assessed in terms of favorable changes in cell wall constituents, protein content and in vitro DM digestibility of the MS. Sorghum based inoculum (seed culture) of Ganoderma lucidum to treat the MS was prepared. The 50 g DM of MS taken in autoclavable polypropylene bags was mixed with a pre-calculated amount of water and the particular nutrient in the straw to attained the desired levels of water and nutrient concentration in the substrate. A significant progressive increase in biodegradation of DM (p<0.001), NDF (p<0.01) and ADF (p<0.05) was observed with increasing levels of moisture. Among the cell wall constituents the loss of ADF fraction was greatest compared to that of NDF. The loss of DM increased progressively as the fermentation proceeded and maximum DM losses occurred at 28 days after incubation. The protein content of the treated MS samples increased linearly up to the day $21^{th}$ of the incubation and thereafter declined at day $28^{th}$, whereas the improvement in in vitro DM digestibility were apparent only up to the day $14^{th}$ of the incubation under SSF and there after it declined. The acid detergent lignin (ADL) degradation was slower during the first 7 days of SSF and thereafter increased progressively and maximum ADL losses were observed at the day $28^{th}$ of the SSF. The biodegradation of DM and ADL was not affected by the variation in incubation temperature. Addition of urea was found to have inhibitory effect on fungal growth. The effect of both the levels (0.25 and 0.50) of SSP addition in the substrate, on DM, NDF, ADF, cellulose and ADL biodegradation was similar. Similarly, the protein content and the in vitro DM digestibility remain unaffected affected due to variable levels of the SSP inclusion in the substrate. From the results it may be concluded that the incubation of MS with 60 percent moisture for 21 days at $35^{\circ}C$ with 0.25 percent SSP was most suitable for MS treatment with Ganoderma lucidum. Maximum delignification, enrichment in the protein content and improvement in in vitro DM digestibility were achieved by adopting this protocol of bioprocessing of MS.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.424-434
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• 1989

The rationale for the use of fungi in treating waste streams from food processing plants I~as been that of incorporating the dissolved and suspending nutrients into a macroscopic organism which can be filtered out readily. In order for a process using fungi to meet these objectives we examined a strain of fungi, Aspergillus fumigatus, which grew well on a variety of polysaccharide-containing materials and showed both efficient BOD removal and high quality protein recovery. In this experiment the fungal choice was based on the laboratory screening studies where the criteria used was BOD and COD reduction, growth response, mycelial yield, and the ability to compete with the natural flora. In the fermentation system used far the continuous culture of Aspergillus fumigatus the best combination of operating variables, inoculum ratio, temperature, initial pH, fermentation time and agitation rate was 5%(v/v), $35{\sim}40^{circ}C,\;pH\;4.5{\sim}5.0$, 2days and 150rpm, respectively. The fungus reduced BOD and COD to 94.0 and 90.4%, respectively and 3.15g of dry mycelium per liter of alcohol waste was harvested during 48hr of incubation time. The protein efficiency ratios for the control diet and the experimental diet containing the fungal protein were $3.42{\pm}0.15$ and $3.40{\pm}0.43$, respectively.

• Microbiology and Biotechnology Letters
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• v.45 no.2
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• pp.162-167
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• 2017

For the production of bioethanol by the synchronous saccharification and fermentation (SSF) process, bio-capsule formation was attempted. Many saccharifying fungal strains and fermentative yeast strains were first screened. Aspergillus sp. BCNU 6200, Penicillium sp. BCNU 6201, and P. chrysogenum KACC 44363 were found to be excellent producers of saccharifying enzymes such as ${\alpha}$-amylase and glucoamylase. Saccharomyces cerevisiae IFO-M-07 showed the highest ethanol productivity among the tested strains. Secondly, we determined the optimal conditions for pellet formation, and those for bio-capsule formation. All the tested fungal strains formed pellets, and the optimal conditions for bio-capsule formation were $28^{\circ}C$ and 120 rpm. Lastly, SSF process was performed using a bio-capsule. An ethanol yield of 3.9% was achieved by using the Aspergillus sp. BCNU 6200 bio-capsule (Aspergillus sp. BCNU 6200 + S. cerevisiae IFO-M-07) at $30^{\circ}C$ with shaking at 120 rpm during the 10 days of incubation. The results provide useful information on the application of a bio-capsule in bioethanol production under the SSF process.

• The Korean Journal of Mycology
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• v.15 no.3
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• pp.187-195
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• 1987

Two kinds of heat treatment method for the selective isolation of soil fungi to eliminate the commonest fungi and also to examine the vertical and seasonal distributions of the fungal population were applied to soil samples from two plots around Seoul area. The incubation method at $42^{\circ}C$ and heat treatment at $70^{\circ}C$ were used in this experiment. In the incubation method, the almost all the fungi isolated from two plots were mesophile, while the thermotolerant fungi was Aspergillus fumigatus and thermophilic fungi were Sporotrichum thermophile and Malbranchea pulchella var. sulfrea. The most dominant species isolated by this method was A. fumigatus. Nine genera and fourteen species were isolated from the two plots, and S. thermophile, Talaromyces ucrainicus,Malbranchea pulchella var. sulfrea were new to Korea. From the selection method by heat treatment at $70^{\circ}C$, ten genera and twenty species were isolated. Among these, the most fungi were also mesophile and thermotolerant fungus was A. fumigatus. The most dominant species isolated by this method was T. stipitatus, Talaromyces helicus var. major, Emericella nidulans var. nidulans, Chaetomium subspirale and Neosartorya fisheri var. fisheri were new to Korea. From the two isolation methods, it was found that the total number of soil fungi and frequency of species appeared including dominant ones were the highest at the soils of upper layer while the lowest at the soils of lower layer in its vertical distribution.

• Journal of Mushroom
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• v.14 no.4
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• pp.162-167
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• 2016

Lactic acid bacteria (LAB) producing phenyllactic acid (PLA), which is known as antimicrobial compound, was isolated from button mushroom bed and the isolated LAB was identified to Lactobacillus casei by 16 rRNA gene sequence analysis. Cell-free supernatant (CFS) from L. casei was assessed for both the capability to produce the antimicrobial compound PLA and the antifungal activity against three fungal pathogens (Rhizoctonia solani, Botrytis cinerea, and Collectotricum aculatum). PLA concentration was investigated to be 3.23 mM in CFS when L. casei was grown in MRS broth containing 5 mM phenylpyruvic acid as precursor for 16 h. Antifungal activity demonstrated that all fungal pathogens were sensitive to 5% CFS (v/v) of L. casei with average growth inhibitions ranging from 34.58% to 65.15% (p < 0.005), in which R. solani was the most sensitive to 65.15% and followed by C. aculatum, and B. cinerea. The minimum inhibitory concentration (MIC) for commercial PLA was also investigated to show the same trend in the range of 0.35 mg mL-1 (2.11 mM) to 0.7 mg mL-1 (4.21 mM) at pH 4.0. The inhibition ability of CFS against the pathogens were not affected by the heating or protease treatment. However, pH modification in CFS to 6.5 resulted in an extreme reduction in their antifungal activity. These results may indicate that antifungal activities in CFS was caused by acidic compounds like PLA or organic acids rather than protein or peptide molecules.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1687-1695
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• 2016

Ochratoxin A (OTA), a mycotoxin, contaminates agricultural products and poses a serious threat to public health worldwide. Microbiological methods are known to be a promising approach for OTA biodegradation because physical and chemical methods have practical limitations. In the present study, a total of 130 fungal isolates obtained from 65 traditional Korean meju (a fermented starter for fermentation of soybeans) samples were examined for OTA-biodegradation activity using thin-layer chromatography. Two fungal isolates were selected for OTA-biodegradation activity and were identified as Aspergillus tubingensis M036 and M074 through sequence analysis of the beta-tubulin gene. After culturing both A. tubingensis isolates in Soytone-Czapek medium containing OTA (40 ng/ml), OTA-biodegradation activity was analyzed using high-performance liquid chromatography (HPLC). Both A. tubingensis strains degraded OTA by more than 95.0% after 14 days, and the HPLC analysis showed that the OTA biodegradation by the A. tubingensis strains led to the production of ochratoxin α, which is much less toxic than OTA. Moreover, crude enzymes from the cultures of A. tubingensis M036 and M074 led to OTA biodegradation of 97.5% and 91.3% at pH 5, and 80.3% and 75.3% at pH 7, respectively, in a buffer solution containing OTA (40 ng/ml) after 24 h. In addition, the OTA-biodegrading fungi did not exhibit OTA production activity. Our data suggest that A. tubingensis isolates and their enzymes have the potential for practical application to reduce levels of OTA in food and feed.