The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 11,493 M/T in 2014. This study examined changes in decomposition-related enzyme activity secreted by the microorganisms isolated from button mushroom composts. Among the isolated microorganisms, bacterial strains CY-36 were the most dominant and had the highest enzyme activities. 16S rDNA sequencing analysis showed 99% similarity of CY-36 to Bacillus amyloliquefaciens. To define the optimum conditions for the mass production of CY-36, we have investigated optimum culture conditions and effects of various nutrient source on the bacterial growth. The optimum initial pH and temperature were determined as pH 5.0~8.0 and 30°C, respectively. The optimal culture medium for the growth was determined as follows: 2.0% dextrin, 1.0% yest extract, 0.5% NaNO3, 3 mM MgSO4, and 0.6% valine. Enzymatic activities of CMCase and PGase secreted by CY-36 were the most prominent and CMCase activity were optimal at 40°C and pH 7.0, and PGase activity were 50°C and pH 6.0. The activity of CMCase was rapidly decreased at more than 4°C and pH 5.0, and the activity of PGase was rapidly decreased at more than 30°C but didn’t affect as pH change. Accordingly, Bacillus amyloliquefaciens CY-36 was potentially useful on the fermentation stimulation and softening of rice straw in the process of fermentation for mushroom cultivation.
This study examined changes in decomposition-related enzyme activity secreted by the microorganisms isolated from button mushroom composts. Among the isolated microorganisms, bacterial strains CY-24 were the most dominant and had the highest enzyme activities. 16S rDNA sequencing analysis showed 97% similarity of CY-24 to Bacillus licheniformis. To define the optimum conditions for the mass production of CY-24, we have investigated optimum culture conditions and effects of various nutrient source on the bacterial growth. The optimum initial pH and temperature were determined as pH 6.0 and 30°C, respectively. The optimal culture medium for the growth was determined as follows: 0.3% mannose, 1.5% yest extract, 0.8% (NH4)2HPO4, 2 mM MnSO4, and 0.5% asparatic acid. Enzymatic activities of CMCase and PGase secreted by CY-24 were the most prominent and CMCase activity were optimal at 50~60°C and pH 6.0, and PGase activity were 60°C and pH 6.0. The activity of CMCase was inhibited by metal ions including Ca+ and Cu+, while the activity of PGase didn’t affect. The activity of CMCase was rapidly decreased at more than 30°C and pH 7.0, and the activity of PGase didn’t affect as temperature change but was rapidly decreased at more than pH 5.0. Accordingly, This strain was potentially useful on the fermentation stimulation and softening of rice straw in the process of fermentation for mushroom cultivation.
‘Nongjin-go’ is a new breed strain of Lentinula edodes, saw-dust bag variety. It is a cross combination of dikaryonLentinula edodes ASI 3305mut and monokaryon L5-16 of L. edodes ASI 3305(Sanjo701ho). We crossbred them by 2011 andverified productive capacity from 2012 to 2013 in Rural Development Administration. Optimum temperature of mycelial growthis 30oC and it of fruit-body primodium formation is range from 15 to 23oC. Nongjigo is agricultured at mid-high temperaturewell. Fruiting body is platy-hemisphere, light brown and centralizing. And bast is formed around edge of pileus. Yield productionsper period is regular than ‘Sanjo701’. Plastic bag culture medium is 1.5 kilogram and culture periods are 90~100 days. As itsbrowning of pileus in culture is a little slow, Light and ventilation is needed a lot in light-culturing. Humidity is controlled properlyfor its color in fruit-body growing. Tested culture medium is consisted of 80% Oak-Tree saw-dust and 20% rice-bran.
수집한 46개의 균주를 배양하여 rDNA의 ITS 염기서열 분석으로 유전적 계통분류 한 결과, Heiricum속이 아닌 균 주가 2균주가 있었음을 확인하였다. 본 결과를 바탕으로 효능이 있는 것으로 밝혀진 H.erinaceus와 가까운 유연관 계를 지니는 종들을 위주로 계통별로 균사 생장실험, 자실 체 발생조사 등을 연구할 예정이다. 또한 H.erinaceus은 아니지만, 생리활성효능이 뛰어난 종의 유무를 테스트하여 기존의 품종보다 효능 면에서 뛰어난 균주를 선발 교잡할 예정이다. 이와 같은 연구를 통해 우수품종을 선발하여 최 적 환경조건 테스트까지 거친다면 노루궁뎅이 버섯 소비 시장 구축에 도움이 되리라 생각된다.