• 한국미생물·생명공학회지
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• 제23권6호
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• pp.641-646
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• 1995

During the screening of inhibitors of melanin biosynthesis from microbial secondary metabolites, a fungal strain MR304 which was capable of producing high level of an inhibitor was selected. Based on taxonomic studies, this fungus could be classified as Trichoderma harzianum. The active compound (MR304-1) was purified from culture broth by Diaion HP-20 column chromatography, ethylacetate extraction, Sephadex LH-20 column chromatographv and HPLC. The inhibitor was identified as 3-(1,5-dihvdroxy-3-isocyanocyclopent-(E)-3-envl)prop-2-enoate by spectroscopic methods of UV, ESIMS, $^{1}$H-NMR, $^{13}$C-NMR, NOE, HMQC and HMBC. MR304-1 showed strong mushroom tyrosinase inhibitory activity with IC$_{50}$ value of 0.25 $\mu $g/ml. It inhibited melanin biosynthesis with 15 mm inhibition zone at 30 $\mu $g/paper disc in Streptomyces bikiniensis, a bacterium used as an indicator organism in this work. It also inhibited melanin biosynthesis in B16 melanoma cells with a niinimum inhibitory concentration of 0.05 $\mu $g/ml.

• KSBB Journal
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• 제10권2호
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• pp.166-169
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• 1995

감 자 Rhizoctoηia stem canker 방 제 용 의 Trichoderma harzianum A Tee 52445 의 포자를 각종 천연담체에 고정화시킨 후 발아율과 강도 벚 점착성 등의 물성을 조사하였다. 천연담체 중 gelatin과 감자 전분 젤에 포자를 고정화시켰을 때 각각 2.81 % 와 2.90%의 발아율을 보였고 강도와 점착성은 감자 전분 고정화 겔보다 gelatin 고정화 겔이 우수하였 다 .. Gelatin에 몇 종의 물성 이 우수한 담체를 섞 어 서 만든 혼합담체에 포자를 고정화시 켰을 경우 물성 은 개선이 되었으냐 발아율은 오히려 낮아졌고 1% 의 corn steep liquor를 gelatin에 첨가하여 포자를 고정화시켰을 때 말아율이 약 0.6% 상승되었다.

• Mycobiology
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• 제38권2호
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• pp.113-117
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• 2010

Trichoderma strains were evaluated under field conditions to assay their efficacy in suppressing Alternaria fruit rot disease and promoting chili plant growth. The experiment was conducted at the Botanical Garden, Rajshahi University, Bangladesh from July 2006 to March 2007. Application of Trichoderma harzianum IMI 392432 significantly (p = 0.05) suppressed the disease compared to Alternaria tenuis (T2) treatment and improved both growth and yield. The treatment T4 (T. harzianum IMI-392432 + A. tenuis) was most effective in reducing disease percentage (72.27%) compared to A. tenuis (T1) treatment. The highest seed germination rate (85.56%) and the highest growth and yield (12.5 g/plant) was also recorded in the same treatment (T4), followed by T5 (T. harzianum IMI-392433 + A. tenuis), T6 (T. harzianum IMI-392434 + A. tenuis), T2 (T. virens IMI-392430 + A. tenuis), and T3 (T. pseudokoningii IMI-392431 + A. tenuis) treatment, while single treatment with A. tenuis significantly decreased these values.

• The Plant Pathology Journal
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• 제21권3호
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• pp.221-228
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• 2005

A total of 179 isolates of Trichoderma spp. were collected from oyster mushroom substrates in Korea. On the basis of morphological and cultural characteristics, Trichoderma isolates were divided into seven groups, namely T. atroviride, T. citrinoviride, T. harzianum, T. longibrachiatum, T. virens, and two unidentified species, referred to as Trichoderma sp. 1 and 2. The predominant species was Trichoderma sp. 2 (n=86) followed by Trichoderma sp. 1 (n=52). Trichoderma sp. 1 and 2 were morphologically distinct not only from the other species of Trichoderma reported but also from each other in the characteristics such as mycelial growth rate, colony appearance, shape of conidia and conidiophores and branching pattern of phialides, although branching pattern of phialides of Trichoderma sp. 1 was similar to that of T. harzianum. In virulence test, the degree for compost colonization of Trichoderma sp. 2 was significantly greater than that of the other Trichoderma species. Trichoderma sp. 2 was found to be the main cause of green mold disease in oyster mushroom production. More work including molecular characterization is needed to confirm the species of Trichoderma sp. 1 and 2.

• 한국미생물·생명공학회지
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• 제31권3호
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• pp.257-263
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• 2003

고체상태배양에서 섬유소분해효소의 고 생산을 위해 기질로서 다양한 섬유순폐기물을 검토한 결과, 주정박과 볏짚을 1:1의 혼합기질로 사용하였을 때 13.98 FPA를 얻었다. 효소생산을 높이기 위해 주정박과 볏짚의 혼합기질에 질소원으로서 콩비지를 1:1:1로 혼합하였을 때 15.22 FPA의 효소활성을 얻을 수 있었다. 이때의 최적의 함수율, pH, 온도는 각각 70%, 5.0, 3$0^{\circ}C$이었다. 최적배양조건에서 배양 5일째 FPA, CMCase, Xylanase, $\beta$-glucosidase 및 Avicelase의 효소활성은 각각 15.22, 69.1, 83.9, 29.2 및 4.2 unit/g-SDW이었다. T. harzianum FJI의 섬유소폐기물을 이용한 고체상 태배양의 경제적인 효소생산은 섬유소폐기물의 생물학적 당화기술에 크게 기여할 것이다.

• The Plant Pathology Journal
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• 제35권6호
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• pp.674-683
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• 2019

Some species of the Trichoderma genus are reported as the major problem in oak wood mushroom production in Korea. In spite of economic loss by the fungi, scientific information on airborne Trichoderma species is not much available. To generate information for disease management development we analyzed airborne Trichoderma. A total of 1,063 fungal isolates were purely obtained from indoor air sampling of cultivation houses used for oak wood mushroom using sawdust media. Among the obtained isolates, 248 isolates were identified as Trichoderma fungi including T. harzianum, T. atroviride, T. citrinoviride, and T. pseudokoningii, by morphological and molecular analysis. T. harzianum was dominant among the four identified species. All the four Trichoderma species grew fast on solid nutrient media tested (potato dextrose agar [PDA], malt extract agar [MEA], Czapek's Dox + yeast extract agar [CYA] and cornmeal dextrose agar). Compact mycelia growth and mass spore production were better on PDA and CYA. In addition, T. harzianum and T. citrinoviride formed greenish and yellowish mycelium and spores on PDA and CYA. Greenish and yellowish pigment was saturated into PDA only by T. pseudokoningii. These four Trichoderma species could produce extracellular enzymes of sawdust substrate degradation such as β-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, and protease. Their mycelia inhibited the growth of oak wood mushroom mycelia of two tested cultivars on dual culture assay. Among of eleven antifungal agents tested, benomyl was the best to inhibit the growth of the four Trichoderma species. Our results demonstrate that the airborne Trichoderma fungi need to be properly managed in the cultivation houses for safe mushroom production.

• 아시안잔디학회지
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• 제12권4호
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• pp.211-220
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• 1998

Cellulose-degrading fungi were idenfied as Rhizoctonia solani AG2-2(IV), T. harzianum and C. cochliodes. Rhizoctonia solani AG2-2(IV) grows better in the acidified media of pH 4 and 5 than pH 6 and 7. Mycelial growth of T. harzianum and C. cochliodes was also higher in pH 4 and 5 than in pH 6 and 7. In order to relate the above findings to nutrient utilization, mycelial growth of R. solani AG2-2(IV) are evaluated with various carbon sources. R. solani AG2-2(IV) grows well in the order of mannose, cellobiose, glucose, xylose and arabinose. However, mycelial dry weights of T. harzianum were 98.7, 78.0, 72.3, 43.7 and 32.3mg in glucose, mannose, cellobiose, xylose, and arabinose, respectively. Mycelial dry weight of C. cochilodes was 118, 65, 57, 49, and 16mg in mannose, cellobiose, xylose, glucose, and arabinose, respectively. Result of cellulase assay of R. solani AG2-2(IV) and soil fungi was reffered as, R. solani AG2-2(IV) produced more cellulase on CMC substrate than on CEL and secretes more enzyme in floated condition than in water-immersed condition. T. harzianum secreted less amount of cellulase than R. solani AG2-2 and C. cochliodes. T. harzianum produced no enzyme on CEL under water-immersed condition. C. cochliodes produced similar amounts of cellulase on either CMC or CEL under both water-immersed and floated condition.

• Journal of Microbiology and Biotechnology
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• 제18권9호
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• pp.1537-1543
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• 2008

We tested Trichoderma harzianum as a biocontrol agent for Rhizoctonia solani AG2-1, using six natural antifungal materials to improve its efficacy. Among the six materials tested, peony (Paeonia suffruticosa) root bark (PRB) showed the strongest antifungal activity against R. solani AG2-1, and was not antagonistic to T. harzianum. Scanning electron microscopy showed that treatment with PRB extract resulted in shortened and deformed R. so/ani AG2-1 hyphal cells. The control of radish damping-off caused by R. so/ani AG2-1 was greatly increased by combined treatments of T. harzianum and PRB, as compared with either of the two treatments alone, with the control effect increased from 42.3-51.5% to 71.4-87.6%. The antifungal compound in PRB, which was isolated in chloroform and identified as paeonol by mass spectrometry, $^1H$ NMR, and $^{13}C$ NMR analyses, inhibited the growth of R. so/ani AG2-1 but not that of T. harzianum. Thus, PRB powder or extract may be used as a safe additive to T. harzianum to improve the control of the soil borne diseases caused by R. so/ani AG2-1.

• Journal of Microbiology and Biotechnology
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• 제7권3호
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• pp.161-166
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• 1997

Nuclei were isolated from the protoplasts of Trichoderma harzianum T95 and treated with colchicine, a polyploid inducer. The nuclei were transferred into the protoplast of multi-auxotrophic Gliocladium virens G88 which cannot grow in minimal medium. The protoplast of G. virens G88 carrying the transferred nuclei were regenerated in a regeneration minimal medium containing $17{\mu}g/ml$ of chloroneb as a haploid inducer. Six intergeneric hybrids between G. virens and T. harzianum were isolated from the regeneration minimal medium. The hybrids could be classified into three types according to morphology, those with an isozyme pattern, those with an protein band and those with an randomly amplified polymorphic DNA(RAPD) pattern produced by random primers and repetitive sequences. The first group was identified to be a haploid recombinant, the second group a heterokaryon, and the third appeared to be petite.

• Journal of Microbiology and Biotechnology
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• 제18권7호
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• pp.1335-1341
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• 2008

The cell wall material from fruiting bodies of Laetporus sulphureus has been suggested as a new alternative to mutan for the mutanase induction in Trichoderma harzianum. Structural analyses revealed that the cell wall fraction from this polypore fungus contained 56.3% of (1$\rightarrow$3)-linked $\alpha$-glucans. When the strain T. harzianum F-340 was grown on a cell wall preparation from L. sulphureus, the maximal enzyme productivity obtained after 3 days of cultivation was 0.71 U/ml. This yield was about 1.8-fold higher than that achieved on mutan, known so far as the best, but expensive and inaccessible, inducer of mutanase production. Cell-wall-induced mutanase showed a high hydrolytic potential in reaction with a dextranase-pretreated mutan, where maximal degrees of saccharification and solubilization of this biopolymer (80% and 100%, respectively) were reached in 3 h at 45$^{\circ}C$. The mutanase preparation was also effective in degradation of streptococcal mutan and its removal from oral biofilms, especially in a mixture with dextranase.