• 한국버섯학회지
• /
• 제10권3호
• /
• pp.109-114
• /
• 2012

느타리 버섯류의 새로운 품종을 개발하기 위하여 고품질의 짙은 회색느타리 신품종을 육성하였다. 2003년부터 2004년까지 느타리 유전자원의 특성검정을 하였다. 2008년에 육종모본수한과 '농기201호'의 단핵체간 교잡하여 04-154 교잡주를 육성하였다. 이 교잡주 04-154와 품종 '청풍'의 단핵체와 다시 교잡하여 우수한 Po2008-275를 선발하여 특성검정, 확대재배를 실시하여 농작물 직무육성 신품종 선정심의회에서 '구슬'로 명명되었다. 주요특성으로 균사 생장 적온이 $25{\sim}30^{\circ}C$이며 버섯 원기형성 및 발생 온도는 $10{\sim}16^{\circ}C$이였다. 자실체의 갓 색깔은 짙은 회색으로 자연 상태에서 봄, 가을에 재배가 알맞은 특성을 가지고 있다. 균사체 배양기간은 25~30일이며 균 긁기 후 초발이소요일수는 3~5일로 온도가 높을수록 단축된다. 자실체 형태는 얕은 깔때기형이다. 대굵기는 $16.8{\pm}1.6mm$, 대길이는 $51.0{\pm}4.4mm$로 다른 느타리 종에 비해 자실체 대가 굵고 다소 짧은 편이다. 자실체 수량은 상자 당($43{\times}43{\times}11cm$) 1,545g으로 04-154 계통친이 100일 때 '구슬' 137, '청풍'이 146이었다. 가변특성으로는 감자배지와 버섯완전배지에서 균사를 배양한 결과 버섯완전배지에서 생장이 양호하였다. 또한 3종류의 primer를 이용하여 새로운 품종 '구슬'과 모균주에 대한 DNA profile을 분석한 결과 primer URP 1, primer URP 2, primer URP 5에서 양친주의 주요 밴드를 가지며 대조구인 '춘추2호'와는 뚜렷하게 구분되었다. 신품종 느타리 '구슬'은 소비자들이 가장 선호하는 짙은 회색의 갓을 나타내어 고품질을 요구하는 소비자를 만족시키는데 기여 할 것으로 기대된다.

• Journal of Microbiology and Biotechnology
• /
• 제15권5호
• /
• pp.1028-1038
• /
• 2005

To elucidate phylogenetic relationships of Phellinus and its related genera, nuclear internal transcribed spacer and mitochondrial small subunit ribosomal DNA sequences from 65 strains were determined and compared. The combined dataset of two sequences increased informative characters and led to the production of trees with higher levels of resolution. Phylogenetic analysis of the combined dataset revealed thirteen evolutionary lineages and several unresolved species that were together subdivided into two large clusters consisting of oligonucleate species and binucleate species. These results coincided with previous cytological, morphological, and molecular studies. It is newly recognized that the Phellinus linteus complex forms a sister clade to Inonotus, and that Fulvifomes is somehow related to Inocutis. The Phellinus linteus complex of dimitic perennial taxa made an independent clade from Inonotus and suggested that hyphal miticity and fruitbody permanence had enough phylogenetic significance to keep the complex within the traditional genus Phellinus. Taxa lacking setae were clustered into Fulvifomes, Phylloporia, Inocutis, and Fomitiporia, and the first three were closely related sister groups, but Fomitiporia was a genus distantly related to them. Several taxa with branched setae were shown among distantly related genera. Molecular evidence indicated that the ancestral nuclear type could be a binucleate feature, and that there might be parallel gains of branched setae and parallel losses of setae in the Hymenochaetales.

• Journal of Microbiology and Biotechnology
• /
• 제12권2호
• /
• pp.249-257
• /
• 2002

Pseudomonas fluorescens GL20 is a plant growth-promoting rhizobacterium that produces a large amount of hydroxamate siderophore under iron-limited conditions. The strain GL20 considerably inhibited the spore germination and hyphal growth of a plant pathogenic fungus, Fusarium solani, when iron was limited, significantly suppressed the root-rot disease on beans caused by F. solani, and enhanced the plant growth. The mechanism for the beneficial effect of strain GL20 on the disease suppression was due to the siderophore production, evidenced by mutant strains derived from the strain. Analysis of the outer membrane protein profile revealed that the growth of strain GL20 induced the synthesis of specific iron-regulated outer membrane proteins with molecular masses of 85- and 90 kDa as the high-affinity receptors for the ferric siderophore. In addition, a cross-feeding assay revealed the presence of multiple inducible receptors for heterologous siderophores in the strain. In order to induce increased efficacy and potential in biological control of plant disease, a siderophore-overproducing mutant, GL20-S207, was prepared by NTG mutagenesis. The mutant GL20-S207 produced nearly 2.3 times more siderophore than the parent strain. In pot trials of beans with F. solani, the mutant increased plant growth up to 1.5 times compared with that of the parent strain. These results suggest that the plant growth-promoting P. fluorescens GL20 and the genetically bred P. fluorescens GL20-S207 can play an important role in the biological control of soil-borne plant diseases in the rhizosphere.

• 약학회지
• /
• 제59권6호
• /
• pp.259-265
• /
• 2015

In recent, there are increasing reports about pharmacological activities of Crataegi Fructus which has been used for many centuries as medicinal and food sources in East Asia. However, its antifungal efficacy needs to be investigated. Thus, in the current study, we determined synergistic antifungal activity of the Crataegi Fructus extract (CFE) when combined with fluconazole (FLC) against disseminated candidiasis due to Candida albicans. This fungus is one of the most problematic fungal pathogens. Data resulting from a microdilution susceptibility test showed that CFE had a dose-dependent antifungal activity. When the extract was combined with FLC, the activity was synergistic. For example, the antifungal activity by the combination of CFE at $20{\mu}g/ml$ plus FLC at $0.1{\mu}g/ml$ was 4 times more effective than antifungal activity by FLC alone at the same concentration (P<0.05). In the murine model of disseminated candidiasis, the combination therapy potentiated resistance of mice, resulting in 80% of C. albicans-infected animals surviving the entire period of 40 days observation, whereas mice given CFE alone or FLC alone all died with 17 and 23 days, respectively, although they survived longer than the untreated control animals (P<0.05). The CFE's antifungal activity seemed to be related to the blockage of hyphal production of C. albicans yeast cells. In summary, CFE has a synergistic antifungal activity, which can be produced by combining CFE with FLC. Thus, our data strongly indicate that CFE may be a potential candidate as an antifungal agent for combination therapy.

• 한국미생물·생명공학회지
• /
• 제13권3호
• /
• pp.273-278
• /
• 1985

새로운 페니실린 발효방법으로서, Penicillin chrysogenum의 포자를 담체의 미세구멍 조직에 흡착시킨 후 배양하여 얻은 균사증식담체를 이용하여 페니실린 발효를 시도하였다. 고정화 담체로써는 Celite가 가장 효율적이었으며, 이때 균사는 담체의 내부에서부터 포자가 발아하여 담체의 표면에서 증식하기 때문에 매우 안정된 biofilm growth를 얻을 수 있었다. 프라스크 배양에서 담체의 양을 5-10% 첨가하였을 때 세포의 증식과 페니실린의 생산이 전통적인 dispersed filamentous growth 에 의한 발효방법보다 현저히 증가되었다. 그러나 두 경우 모두 세포의 활성은 1900 unit/mg-cellㆍhr로 일정하였다. 균사증식 담체를 이용하여 유동층 발효조에서 반연속식으로 발효를 진행시킨 결과 페니실린의 연속생산이 가능함을 발견하였다. 그러나 발효조내에서 biofilm growth시 film두께의 조절과 페니실린 생산성을 일정수준으로 오랫동안 유지시킬 수 있는 방법이 앞으로 연구되어야 할 것으로 판단되었다.

• Journal of Microbiology and Biotechnology
• /
• 제31권6호
• /
• pp.890-901
• /
• 2021

The 11α-hydroxylation of canrenone can be catalyzed by Aspergillus ochraceus in bioreactors, where the geometry of the impeller greatly influences the biotransformation. In this study, the effects of the blade number and impeller diameter of a Rushton turbine on the 11α-hydroxylation of canrenone were considered. The results of fermentation experiments using a 50 mm four-blade impeller showed that 3.40% and 11.43% increases in the conversion ratio were achieved by increasing the blade number and impeller diameter, respectively. However, with an impeller diameter of 60 mm, the conversion ratio with a six-blade impeller was 14.42% lower than that with a four-blade impeller. Data from cold model experiments with a large-diameter six-blade impeller indicated that the serious leakage of inclusions and a 22.08% enzyme activity retention led to a low conversion ratio. Numerical simulations suggested that there was good gas distribution and high fluid flow velocity when the fluid was stirred by large-diameter impellers, resulting in a high dissolved oxygen content and good bulk circulation, which positively affected hyphal growth and metabolism. However, a large-diameter six-blade impeller created overly high shear compared to a large-diameter four-blade impeller, thereby decreasing the conversion ratio. The average shear rates of the former and latter cases were 43.25 s^-1 and 35.31 s^-1, respectively. We therefore concluded that appropriate shear should be applied in the 11α-hydroxylation of canrenone. Overall, this study provides basic data for the scaled-up production of 11α-hydroxycanrenone.

• The Plant Pathology Journal
• /
• 제34권6호
• /
• pp.470-479
• /
• 2018

The rice blast pathogen Magnaporthe oryzae is a global threat to rice production. Here we characterized RHO2 gene (MGG_02457) that belongs to the Rho GTPase family, using a deletion mutant. This mutant ${\Delta}Morho2$ exhibited no defects in conidiation and germination but developed only 6% of appressoria in response to a hydrophobic surface when compared to the wild-type progenitor. This result indicates that MoRHO2 plays a role in appressorium development. Furthermore, exogenous cAMP treatment on the mutant led to appressoria that exhibited abnormal morphology on both hydrophobic and hydrophilic surfaces. These outcomes suggested the involvement of MoRHO2 in cAMP-mediated appressorium development. ${\Delta}Morho2$ mutation also delayed the development of appressorium-like structures (ALS) at hyphal tips on hydrophobic surface, which were also abnormally shaped. These results suggested that MoRHO2 is involved in morphological development of appressoria and ALS from conidia and hyphae, respectively. As expected, ${\Delta}Morho2$ mutant was defective in plant penetration, but was still able to cause lesions, albeit at a reduced rate on wounded plants. These results implied that MoRHO2 plays a role in M. oryzae virulence as well.

• Journal of Microbiology and Biotechnology
• /
• 제30권2호
• /
• pp.206-215
• /
• 2020

Trichoderma reesei is the major filamentous fungus used to produce cellulase and there is huge interest in promoting its ability to produce higher titers of cellulase. Among the many factors affecting cellulase production in T. reesei, the mycelial phenotype is important but seldom studied. Herein, a close homolog of the Neurospora crassa COT1 kinase was discovered in T. reesei and designated TrCOT1, which is of 83.3% amino acid sequence identity. Functional disruption of Trcot1 in T. reesei by RNAi-mediated gene silencing resulted in retarded sporulation on potato dextrose agar and dwarfed colonies on minimal medium agar plates containing glucose, xylan, lactose, xylose, or glycerol as the sole carbon source. The representative mutant strain, SUS2/Trcot1i, also displayed reduced mycelia accumulation but hyperbranching in the MM glucose liquid medium, with hyphal growth unit length values decreased to 73.0 ㎛/tip compared to 239.8 ㎛/tip for the parent strain SUS2. The hyperbranching phenotype led to slightly but significantly increased cellulase secretion from 24 to 72 h in a batch culture. However, the cellulase production per unit of mycelial biomass was much more profoundly improved from 24 to 96 h.

• 한국잠사곤충학회지
• /
• 제41권1호
• /
• pp.36-40
• /
• 1999

눈꽃 동총하초의 인공재배를 위한 최적배양조건을 구명하기 위해 본 시험을 수행하였으며 그 결과 colony는 직경 32 mm/14 days로 생장하였으며 분생포자는 불규칙한 장타원형으로 평균 4.07${\times}$1.56 ${\mu}$m 크기이며 분생자병은 투명다발의 분자형으로 발생하였다. 자실체는 지상부에서 30~50 mm로 다발형태로 발생하며 평균 55개의 분지를 형성한다. 종균배양 액체배지 선발결과 PD배지가 건중량 3.15${\pm}$0.16 mg/50 m/로 균사생장에 가장 효과가 우수하였다. 분생포자 생산 최적 환경조건은 산도 pH 5.0 온도는 24$^{\circ}C$에서 20$^{\circ}C$로 변온을 가한 경우 4.30${\pm}$0.35${\times}$10$^8$ conidia/m/로 기타 처리구에 비해 포자형성율이 가장 우수하였다.

• 생명과학회지
• /
• 제27권2호
• /
• pp.211-216
• /
• 2017

외화유출 감소와 버섯의 생산 단가를 절약하여 농가소득을 증대시킬 목적으로 폐 한방슬러지를 첨가한 배지에서 팽이버섯을 배양할 때 버섯재배를 위한 최적 생육환경 조건을 검토하였다. 그리고 최적 생육한경 조건에서 생산된 팽이버섯 자실체의 특성을 조사하였다. 폐 한방슬러지의 첨가농도는 10%가 적당하였고, 배지의 함수율은 폐 한방슬러지를 첨가하지 않은 대조구와 비슷한 약 65%가 적당하였다. 배양실 내의 온도는 $16^{\circ}C$, 습도는 75%~85%로 설정한 시험구에서 가장 왕성한 균사성장이 이루어졌다. 1,100 ml의 버섯재배용 병을 사용하여 현장실험을 행한 결과 병당 팽이버섯의 수확량은 대조구 및 시험구에서 약 275~282 g으로 거의 비슷하게 얻었다. 흰곰팡이 및 세균성 갈색무늬병 등 버섯질병의 발생은 전혀 관찰할 수 없었다. 그리고 기형버섯 및 2등품버섯 등이 약간 발생하기는 하였으나 전보에 비하여 그 편차가 줄어들어 상당히 균일한 버섯의 생육을 관찰하였다. 팽이버섯 자실체는 백색의 반구형으로 갓의 직경은 약 9.2~9.3 mm, 대의 길이는 약 12.7~12.8 cm, 뚜께는 3.3~3.4 mm로 대조구의 버섯품질과 거의 유사하였다. 버섯부위별 경도는 대조구와 시험구 모두 갓 부분($46.8{\sim}47.6g/cm^2$)보다는 대 부분의 경도($54.6{\sim}57.3g/cm^2$)가 약간 높은 것으로 나타났다. 트랜스지방 및 콜레스테롤은 검출되지 않았으며 100 g당의 열량 및 영양성분은 대조구와 거의 비슷하게 나타났다.