노란달걀버섯은(Amanita javanica) 국내에서 산림법으 로 보호받고 있는 식용 가능한 외생균근성 버섯이나, 중요한 산림자원으로서 활용하기 위한 기초적인 특성 연구에 대한 자료는 부족한 실정이다. 이에 본 연구는 국내 채집 야생버섯 자실체로부터 분리한 노란달걀버섯 NIFoS 1267 균주를 이용하여 PDA 배지 상에서 물리적 요인(온도, pH, 광)과 화학적인 요인(염분, 중금속, 농약)에 따른 균사생장 특성을 조사하였다. 최적의 물리적 환경은 온도가 30oC, pH가 5-6, 암조건으로 배양이었을 때 노란달걀 버섯 균주의 균사생장이 가장 좋은 것으로 나타났다. 화학적 요인으로서 염분은 2.0% 농도 조건까지 버섯균주의 균사 생장이 가능하였다. 50 ppm 농도의 중금속 이온 환경에서 비소(As) 이온은 노란달걀버섯 균주의 균사생장에 영향을 주지 않았으나 카드뮴(Cd)와 납(Pb) 이온은 균사 생장이 불가능하게 하였다. 국내 산림에 사용되고 있는 2가지 농약의 경우, Abamectin 첨가 배지에서는 노란달걀 버섯 균주의 균사 생장에 영향이 없었으나 Acetamiprid, Emamectin benzoate, Thiacloprid가 첨가된 배지 환경에서는 균사 생장이 모두 다 저해 되었다. 본 연구 결과는 향후 상업적 생산을 위한 새로운 자원으로서 노란달걀버섯의 인공재배 연구에 도움이 될 것으로 기대된다.

The use of air cleaners has become popular to quickly remove contaminants present in indoor air such as fine dust and fungi. However, fungal information is rarely available in the filters equipped in the air cleaners. This study was conducted in winter to examine fungal concentration and species in the air cleaner filters of ten residential houses located in Incheon, Seoul, Hwaseong, and Gimpo cities. Fungi were detected in nine out of eleven filters from the ten houses. The level of fungi in the filters ranged from 0 CFU/cm2 to 2,370 CFU/cm2. There were differences in the fungal concentration among the eleven filters. Filters from three houses revealed levels over 1,000 CFU/cm2. The operation time of air cleaners did not seem directly related to the level of fungal concentration. A total of 326 isolates were obtained and classified as six genera belonging to Alternaria, Aspergillus, Cladosporium, Fusarium, Penicillium, and Trichoderma. Among these six genera, 20 species including one Alternaria, one Aspergillus, three Cladosporium spp., two Fusarium spp., eleven Penicillium spp., and two Trichoderma were identified. There were species that cause allergic reaction, pneumoniae, mycosis, and plant disease. Three species were known species of mycotoxin producers. Aspergillus niger, Cladosporium cladosporioides, and Penicillium brevicompactum were the most frequently detected fungi both in the air and in the air cleaner filters. This is the first report of fungal communities present in the air cleaner filters of residential houses in Korea.

Fungus has been regulated as an air contaminant in indoor environments in Korea. To remove the contaminant, air purifiers have been used in houses. However, not much information on the status of fungal contamination in the indoor air of houses is available. The present study was carried out to investigate fungal concentration and species in the indoor air of houses using air purifiers in winter. The results of indoor air sampling of ten houses located in the cities of Incheon, Seoul, Hwaseong, and Gimpo showed that the level of fungi ranged from 9 CFU/ m3 to 782 CFU/m3. Eight out of ten houses showed a level of less than 165 CFU/m3 indicating that the fungal level is generally low. Only one house exceeded the Korean regulatory standard value of 500 CFU/m3. A total of 175 isolates were obtained and classified as three genera belonging to Aspergillus, Cladosporium, and Penicillium. Among these three genera, 15 species including four Aspergillus spp., two Cladosporium spp., and nine Penicillium spp. were identified. Regarding the detection rate of the 15 identified fungal species, A. niger was the most detected species and followed by Cladosporium cladosporioides. Three to six species were present in the individual house that was investigated. Overall, our results showed that the level of fungal concentration and species diversity are low in the indoor air of houses that use air purifiers in winter.

기후 변화에 따른 표고 재배사내 온도와 습도의 변화추이를 알아보기 위하여 5년 동안 봄, 여름, 가을 기간에 걸쳐 국내 49곳의 표고버섯 재배사에서 온도와 습도를 측정 분석하였다. 톱밥배지 재배사의 5년간 평균 온도와 습도는 24.7℃와 60.5%이었다. 원목 재배사의 5년간 평균 온도는 24.4℃, 평균 습도는 60.0%로 나타났다. 여름철 기간 중 온도 평균은 원목재배사의 경우는 2016년 29.8℃, 2017년 29.1℃, 2018년 33.3℃이었으며 톱밥배지 재배사의 경우는 2016년 26.8℃, 2017년 20.4℃, 2018년 24.2℃이었다. 조사 기간 중 30℃가 넘는 고온으로 측정된 재배사는 봄철에 1곳, 여름철에 5곳이었으며 원목 재배사가 5곳을 차지하였다. 원목재배에서 온도가 20℃를 넘지 않는 재배사는 4곳으로 모두 가을에 조사된 온도였다. 본 연구 조사는 기후변화에 대비해 표고 재배사의 경우 원목 재배사 관리에 우선적으로 대비해야 함을 시사하였다.

봄철 천식환자 가정집 9곳에서 실내 공기를 포집하여 부유진균의 농도 및 다양성을 조사하였다. 조사된 천식환자 가정집의 평균 부유진균 농도는 거실 143 CFU/m³, 방 142 CFU/m³ 이었으며 외기보다 낮았다. 이는 다중이용시설 실내공기질 기준법의 권고기준 기준치 500 CFU/m³를 초과하지 않았음을 보여준다. 총 59균주를 분리하였으며 5속 33종으로 동정하였다. 이 중 병원균으로서 인체에 위해성을 가지고 있는 진균은 4속 12종이었다. 동정된 종 중 Cladosporium crousii, Penicillium maximae, Aspergillus protuberus는 국내에 보고되지 않은 미기록 진균 종으로 확인하였다. 이 중 A. protuberus는 국외에서 인체에 질병을 유발시키는 균으로 알려진 진균이다. 이상의 결과는 천식환자 가정에서 진균의 관리는 정량적 수준에서뿐만 아니라 유해종을 파악하여 관리하는 정성적인 수준에서도 이루어져야 함을 제시한다. 본 연구는 봄철 천식환자 가정집에 존재하는 실내 공기 중 부유진균의 농도 및 다양성에 대한 최초의 연구이다.

To obtain basic data on bioaerosols in the indoor environments of houses located adjacent to Gwangyang Iron Works, the concentration and diversity of indoor air molds were comparatively investigated in 33 houses in September of 2016 and 2017, respectively. In areas both adjacent to and nonadjacent to Gwangyang Iron Works, house temperature and humidity ranged from 24~28oC and 47~57%, respectively. Airborne mold concentration was higher in the houses located nonadjacent than in the ones adjacent to the iron works. Interestingly, the level of airborne mold concentration exceeded 500 CFU/m3 in all houses nonadjacent to the iron works. A total of 12 mold species including five pathogenic species were indentified from the investigation. Among the five pathogenic species, the causal agents of otomycosis, Alternaria alternata, Aspergillus fumigatus, and A. niger were present. Overall, Cladosporium cladosporioides was the dominant species. This is the first report on the concentration and diversity of airborne mold in houses located adjacent and nonadjacent to Gwangyang bay industrial complex in Korea.

The potential risk of heavy metals and residual pesticides in imported sawdust media inoculated with oak mushroom cultures is a concern for safe mushroom production in Korea. To obtain preliminary data for a sound analysis of this risk, this study was undertaken to analyze the presence of heavy metals and residual pesticides in the oak mushroom media imported from six different regions in China, between 2013 and 2015. Lead, arsenic, chrome, mercury, and cadmium were analyzed; arsenic, chrome, and mercury were not detected. Lead was detected in the imported oak mushroom media from Jinlin, Shandong, Liaoning, and Tianjin. The detection level of lead ranged from 1.7 to 3.2 mg/kg. Cadmium was detected at a level of 0.028 to 0.037 mg/kg in the media from Shandong and Liaoning. No residual pesticides were detected in any of the samples.

To gather information on the indoor air quality of the greenhouses used for edible oakwood mushroom cultivation, temperature, humidity, and bacterial concentration and species were investigated in 2015 and 2016 in 21 mushroom greenhouses located in ten different regions in Korea. Temperature and humidity of all the mushroom greenhouses ranged from 16.2 to 30.8°C and from 28.2 to 85.6%, respectively. Bacterial concentration exceeded the Korean indoor air quality standard value (800 cfu/m3) in 15 of the 21 mushroom greenhouses. A total of 33 genera and 76 species were identified in the indoor air of the mushroom greenhouses investigated. Of the identified bacteria, 10 genera and 15 species including Acidovorax oryzae, Bacillus infantis, B. licheniformis, Cellulosimicrobium funkei, Ewingella Americana, Exiguobacterium sibiricum, Leclercia adecarboxylata, Lysinibacillus sphaericus, Pseudomonas fulva, Raoultella terrigena, Staphylococcus cohnii, S. haemolyticus, S. saprophyticus, S. sciuri, and Streptomyces sindenensis are among those known to have a harmful effect on human health. These bacteria have been reported to cause sepsis, skin infection, bloodstream infection, bacteremia, spondylitis, peritonitis, acute meningitis, endocarditis and urinary tract infection. The results of this study indicate that continuous hygiene management of indoor air is necessary in the greenhouses used for oakwood mushroom cultivation.

To study the behavior of structures subject to blast loads it is important to calculate the loads due to the explosives accurately, especially in the case of interior explosions. It is known that numerical method based on computational fluid dynamics can estimate relatively accurate blast load due to the interior explosion including reflection effect. However, the numerical method has disadvantages that it is difficult to model the analysis and it takes much time to analyze it. Therefore, in this study, the analytical method which can include the reflection effect of the interior explosion was studied. The target structures were set as the slabs of residential buildings subject to interior explosion that could lead to massive casualties and progressive collapses. First, the numerical method is used to investigate the interior explosion effect and the maximum deflection of the slab which was assumed to be elastic, and compared with the analytical method proposed in this study. In the proposed analytical method, we determine the weighting factor of the reflection effect using the beam theory so that the explosion load calculation method becomes more accurate.