In this study, we investigated the microbial community of oyster mushrooms at different growth stages at the species level. Gram-positive bacteria were predominant in the presterilized medium. On the other hand, Gram-negative bacteria were predominant in the culture-completed medium, post-harvest medium, and fruiting bodies. In addition, Pseudomonas tolaasii, which is known to cause disease in mushrooms, was confirmed in the cultured medium, post-harvest medium, and fruiting bodies, and it was determined that the mycelium culture stage was contaminated, and the reason why no disease occurred was Sphingobacterium psychroaquaticum. It was confirmed that this was because the growth of Pseudomonas tolaasii was suppressed by producing a component called tolacin. As a result of confirming the diversity of microorganisms, it was confirmed that the presterilization medium contains a variety of microorganisms compared to other growth stages, and the diversity decreases in the order of culture completion medium, fruiting body, and post-harvest medium. showed a trend. As a result of microbial similarity analysis, it was confirmed that the cultured medium and the post-harvest medium showed similar microbial communities, and in the case of fruiting bodies, there were some similarities but overall differences.
This study analyzed the effects of different nitrogen sources in substrate composition on the growth of Pleurotus ostreatus, as well as the subsequent changes in flavor and antioxidant activity. The T2, composed of poplar sawdust, beet pulp, cotton seed dregs, and cotton seed coat in a ratio of 40:20:20:20, exhibited the highest yield at 156.6 g. The total polyphenol content and ABTS and DPPH radical scavenging activities were 8.25 mg GAE/g, 70%, and 49%, respectively, showing higher radical scavenging activity compared to the Control and T1. Additionally, varying nitrogen content resulted in distinct aroma patterns and is presumed to influence taste profiles such as sourness, umami, and saltiness.
생태계서비스 상쇄 효과(Trade-off) 규명과 같이 서비스 간 상호관계를 측정하는 것은 한정된 환경자원을 관리하는 측면에서 매우 중요하다. 이에, 본 연구에서는 약 30여 년간 토지 피복이 변화함에 따라 파생된 생태계서비스 우세경향 및 증감을 파악하고, 시간의 경과에 따라 발생한 생태계서비스 상호 간 관계 변화를 추적하였다. 이를 통해 토지 피복 변화와 생태계서비스 변화 간의 관계 및 지역마다 상이한 서비스 변화의 특성을 규명하였다. 연구는 생태계서비스 평가 모델인 InVEST Model을 주로 활용하였고, 평가결과를 0-1사이로 표준화한 후 차원축소기법 중 하나인 주성분 분석을 거쳐 시계열변화를 관찰하고 서비스 상호 간 관계를 파악하였다. 연구 결과, 시가화 지역 면적은 1989년에서 2019년 사이 급격하게 증가했으며, 산림은 2009년에서 2019년 사이 크게 증가하는 양상을 나타냈다. 1989년에서 2019년 사이에 생태계서비스 공급량에 있어 전국적으로 수량 공급은 13.9% 감소, 질소 저류는 10.5% 감소, 인 저류는 2.6% 증가, 탄소 저장은 0.9% 감소, 대기정화는 1.2% 증가, 서식처 질은 3.4% 감소하였다. 우리나라는 지난 30여 년간 시가화 지역이 증가하고, 농경지가 감소하며, 산림이 증가하는 동안 인 저류 기능과 서식처 질 사이에 상쇄 효과를 보였다. 본 연구는 우리나라의 환경관리 정책이 도시화로 인해 하락한 생태계 질을 향상시키고 생태계서비스를 극대화하는데 기여했다는 결론을 도출하였다. 이러한 연구 결과는 정책결정자들이 지속 가능한 자연환경 보전과 생태계 서비스 제공에 중점을 둔 조림 정책을 수립하고 추진하는 데 도움을 줄 수 있다.
Yuzu (Citrus junos) undergoes traditional processing to create preserved yuzu with a sugar content of 50%. This study aimed to produce low-sugar yuzu syrup using artificial or natural sweeteners instead of sugar. Among artificial sweeteners, maltitol showed minimal browning and lack of deposition at high temperatures. The addition of xanthan gum (0.2%) and carboxymethyl cellulose (0.2%) resolved the issue of layer separation and viscosity decrease of yuzu syrup. Alternatively, grain syrup, a natural sweetener, improved viscosity and homogeneity without the additives. Yuzu syrups were developed using yuzu juice and preserved yuzu, with maltitol (20~40%) or grain syrup (50~70%) as the sweetener. Yuzu syrups containing 35% maltitol (M35) or 55% grain syrup (G55) had less than 5% and 10% free sugar, respectively. These syrups exhibited taste patterns similar to commercial yuzu syrup in analysis using an electronic tongue. Furthermore, M35 and G55 contained yuzu flavonoids at concentrations of 19.82 mg/g and 24.09 mg/g, respectively. Antioxidant activity (DPPH, ABTS radical scavenging) of M35 and G55 was equivalent to 10.55, 17.59 mg/100 g of Vitamin C and 97.39, 33.92 mg/100 g of Vitamin C, respectively. Consequently, M35 and G55 offer promising alternatives to preserved yuzu, providing low-sugar yuzu syrups enriched with functional ingredients.
Black chestnut (BC) was obtained through aging of fresh chestnut (FC) at 80℃ for 15 days. Proximate and mineral compositions along with colors of FC and BC were evaluated. With aging, moisture contents decreased by 50%, whereas sugar contents, carbohydrate contents, and calories increased. Contents of minerals (Fe, P, Ca, Na, Mg, K) were significantly higher in FC than in BC, showing an order of Mg < Ca < P < K in both FC and BC. Using a Hunter color system, it was found that lightness (L), redness (a), and yellowness (b) values of FC were higher than those of BC. Antioxidant and cytotoxic activities of hot water and ethanol (50, 80, 100%) extracts prepared from FC and BC were evaluated. Extraction yields were lower with FC than with BC. Among water and ethanol extracts, water extract showed the highest DPPH radical scavenging activity for both FC and BC. IC50 values for ABTS+ radical scavenging activities increased after aging. Cytotoxicities of FC and BC extracts were similar to each other. They were different against various cell lines (3T3, HeLa, and Sarcoma-180). These results suggest that BC could be used as a new processed food using chestnut.
This study developed an IoT-based agricultural well control system and demonstrated it through a control system in the current state of domestic open-field smart farms where systematic management is insufficient due to the difficulty of collecting accurate data such as agricultural water intake and usage. As a result, it was possible to derive the optimal control system test results according to the watering conditions for each schedule by conducting automatic control focusing on periods when there is no precipitation. This means that irrigation can be carried out smoothly during the time when irrigation is needed to improve crop quality and secure farm income, and as a result, it is possible to systematically manage and operate among demonstration farms connected to irrigation, resulting in a shortage of agricultural water and a resolution of supply imbalances.
Biocide dichlofluanid breaks down quickly and accumulates easily in sediment, potentially causing a persistent impact on various marine organisms. We analyzed the potential toxicity of dichlofluanid on major aquaculture species in Korea, Undaria pinnatifida. Female gametophytes of U. pinnatifida were exposed to dichlofluanid at concentrations of 0, 1, 2, 4, 8, 16, and 32 mg L-1, and their survival and relative growth rate were analyzed. The no observed effect concentration (NOEC), lowest observed effect concentration (LOEC), and median lethal concentration (LC50) for female gametophyte survival were determined as 1, 2, and 10.82 (95% CI: 8.87-13.23) mg L-1, respectively. The NOEC, LOEC, and median effective concentration (EC50) for relative growth rate were 1, 2, and 6.58 (95% CI: 6.03-7.17) mg L-1, respectively. Female gametophytes of U. pinnatifida were expected to experience toxic effects at concentrations above 2 mg L-1 of dichlofluanid. These research findings are expected to serve as important reference data for evaluating the toxicity effects of U. pinnatifida in its early life stages when exposed to dichlofluanid.
In this study, we examined the effects of gamma irradiation dosage on the mycelial growth of Auricularia auriculajudae and performed analyses of fruiting body yield, growth characteristics, taste, fragrance, and mineral composition. Assessments of mycelial growth in response to gamma irradiation at different intensities revealed an enhancement in the growth of fungi exposed to irradiation at 200 Gy. Fruiting body yield was also highest at 200 Gy, followed by 800 Gy and the control group. On the basis of these observations, we subsequently applied gamma ray doses of 200 and 800 Gy to examine the effects of irradiation on fungal quality characteristics. In terms of the taste of fruiting bodies, we detected no significant differences among the control, 200 Gy, and 800 Gy groups. Contrastingly, with respect to fragrance, we found that fungi treated with 200 Gy were characterized by a pattern that differed from those of the control and other treatment groups. Furthermore, whereas we detected no significant difference among treatments with respect total dietary fiber content, calcium content was found to be higher in the treatment groups compared with the control group, with the highest content being measured in fungi exposed to 800 Gy irradiation. Copper content was confirmed to be higher in the control group, whereas there were no significant differences between the fungi irradiated with 200 and 800 Gy. Contrastingly, the highest levels of zinc were detected in response to 200 Gy irradiation, followed by 800 Gy. Collectively, our findings thus indicate that gamma irradiation can contribute to promoting increases in the fruiting body yield and mineral contents of mushrooms.
우리나라 여러 해양환경 지역으로부터 확보한 370주의 해양세균, 균류, 미세조류로부터 기초생 리활성(항산화, 항염, 항균, 항암, 항바이러스)을 조사하여 채집지, 분리원, 종(種) 수준에서의 활성결과를 비교하였다. 해양세균의 경우, 일반적으로 유용성이 많이 알려진 Streptomyces 속 과 Bacillus 속에 속하는 균주들이 두드러진 강한 효능이 관찰되었고, 주로 해양퇴적물로부터 유용한 자원을 분리할 수 있었다. 해양균류와 미세조류의 경우에도 종 특이적으로 활성이 강 하게 나타나는 결과를 확인할 수 있었고, 효능 특이적으로 활성을 보이는 결과도 얻을 수 있었 다. 이러한 결과를 바탕으로 추후 특정질병에 선택적으로 효능을 보이는 화학물질 연구 또는 자원 기반 연구 수행 시 유용성을 전제로 한 자원 확보 전략 수립과 산업 활성화를 위한 전 략소재로 우선적 접근이 용이할 수 있는 연구결과라 생각된다. 또한, 이들 결과를 해양바이오 뱅크를 통한 분양소재로 활용함으로써 학계, 산업계에서 활용하여 해양바이오산업 활성화에 좀 더 빠른 접근을 도울 수 있다고 생각한다.
This study explores strategies to address the variability of heat energy using renewable energy and heat grids to achieve carbon neutrality. Renewable energy source introduce fluctuations that can impact the stability of power systems, while heat grids provide a systematic infrastructure for efficient supply of heat energy and power generation. Jeju Island is chosen as a case study, focusing on balance control based on groundwater-based geothermal energy to optimize the distribution of heat energy. The results demonstrate that the 3rd control method is the most effective in maintaining the target temperature in greenhouses, and specific temperature settings and objectives are proposed for each control method based on crop requirements. These research findings contribute to achieving carbon neutrality and reducing power consumption.
Chlorothalonil is continuously introduced into the marine environment and has significant toxic effects on various marine organisms, however, research on its effect on seaweed is limited. Therefore, we analyzed the impact of chlorothalonil on the early life stages of major aquaculture species in Korea, Undaria pinnatifida. U. pinnatifida female gametophytes were exposed to different concentrations of chlorothalonil (0, 0.03, 0.05, 0.10, 0.20, and 0.40 mg L-1), and their survival rate and relative growth rate were analyzed. The no observed effect concentration (NOEC), lowest observed effect concentration (LOEC), and median lethal concentration (LC50) for female gametophyte survival were determined as 0.05, 0.10, and 0.141 (0.121-0.166) mg L-1. NOEC, LOEC, and median effective concentration (EC50) for relative growth rate were 0.10, 0.20, and 0.124 (0.119-0.131) mg L-1. Therefore, female gametophytes of U. pinnatifida are expected to experience toxic effects at concentrations above 0.05-0.10 mg L-1 of chlorothalonil. These research findings are anticipated to serve as crucial reference data for evaluating the effects of chlorothalonil on the health of U. pinnatifida in the early life stages.
In this study, the growth characteristics of Lentinula edodes were confirmed by bean sprout waste(BW) as an alternative raw material for rice bran. The mycelium growth of Sanjo701, a major cultivation variety of L. edodes, was compared between a medium mixed with 8:2(v/v) of oak sawdust and a medium mixed with BW 50% and BW 100%. The mycelium growth in BW 50% was 13.5 cm. Compared to the control, BW 50% increased the diameter of the pileus by 1.6 cm. Additionally, the length of the pileus decreased by 0.4 cm when comparing the growth of the fruit body. In contrast, at BW 50%, the diameter of the pileus decreased by 9.6 cm and the length of the stipe decreased by 1.4 cm. According to analysis of the constituent amino acids, BW 50% showed a lower overall nutritional content than the control, whereas BW 100% had a lower amino acid content than the control. However, glutamic acid and aspartic acid, which are flavor-enhancing ingredients, were observed at levels of 3.954 mg/g and 1.436 mg/g, respectively, in BW 100%. Therefore, if bean sprout by-products are efficiently processed and utilized, it is believed that they will be beneficial to farmers as a substitute for rice bran and reduce the cost of manufacturing substrate
본 연구는 혈중 엽산농도와 대사증후군의 관련성을 살펴보고자 한다. 분석에 사용한 자료는 국 민건강영양조사 2018년도 자료(제7기 3차)를 사용하였으며 본 연구는 만 19세 이상인 성인을 대상으로 혈 중 엽산농도를 측정한 대상자 중 남자 495명, 여자 706명, 총 1,201명을 최종 분석하였다. 자료의 분석은 일반적 특성에 따른 혈중 엽산 차이는 Chi-square와 t- test로, 대사증후군 하부요인들간의 관계는 Pearson 상관관계, 혈중엽산농도와 대사증후군 지표는 로지스틱 회귀분석을 사용하였다. 본 연구 결과에 의하면 혈중 엽산농도와 대사증후군의 하부요인인 허리둘레(r=-0.113, p<0.05), 중성지방(r=-0.086, p<0.05)과 유의미한 음의 상관관계, HDL-cholesterol(r=0.086, p<0.05)은 유의미한 양의 상관관계를 보였 으며 회귀분석결과 HDL-cholesterol의 경우 혈중엽산농도가 정상인 군이 낮은 군에 비하여 유의미하게 높 았다(p<0.05). 따라서 본 연구를 통하여 대사증후군 예방을 위한 적절한 식습관 및 건강 교육프로그램 개 발을 제안한다.
본 연구는 혈중 비타민 E 농도와 대사증후군의 관련성을 살펴보고 비타민 E의 신체에 미치는 영향을 살펴보고자 한다. 분석 자료는 질병관리본부에서 시행한 국민건강영양조사 제7기 3차 (2018년도) 자료를 사용하였으며 본 연구에서는 만 19세 이상 성인은 대상으로 혈중 비타민 E의 농도를 검사한 대상 자 중 남자 944명, 여자 1,080명을 최종 분석하였다. 자료 분석은 일반적 특성에 따른 혈중 비타민 E 농도 차이는 Chi-square와 t- test로, 혈청 비타민 E 농도와 대사증후군 하부요인들 간의 관계는 Pearson 상관 관계로, 혈중 비타민 E 농도와 관련된 대사증후군 지표는 로지스틱 회귀분석을 하였다. 대사증후군의 하부 요인과 혈중 비타민 E의 회귀분석 결과 HDL-cholesterol이 정상군이 과잉군에 비해 높았으며(OR:1.042, CI:1.028-1.056), 중성지방도 정상군에 비해 유의미하게 높았다(OR:1.010, CI:1.009-1.012)(p<0.01). 따 라서 본 연구를 통하여 환자의 연령에 맞는 영양 및 건강프로그램을 개발할 것을 제안한다.
Caldecott medal winners have been recognized as best picture books, and they become one of the most predominantly selected literary works for children. Impacts they have on children’s emotional, social, and linguistic development are well-recognized in various areas such as literacy, literature, and sociology. As educational philosophies embedded in Caldecott medal winners may contribute to their ‘didactic’, sociocultural, and linguistic impacts, this study explores what educational philosophies are embodied in 85 Caldecott medal winners from 1938 to 2022. It classifies them in terms of five major educational philosophies (progressivism, essentialism, perennialism, existentialism, and postmodernism including multiculturalism, feminism, ecology, and metafictive devices). Finally, it traces their prevailing trends from the chronological order in which they are introduced. The findings of this study are as follows: 1) Some educational philosophies such as essentialism and multiculturalism have appeared most frequently while perennialism and progressivism are no longer prevalent modes presented in Caldecott winners; 2) The changes in overall chronological flows of educational philosophies are made from essentialism to postmodernism, especially promoting picture books of metafictive devices. This study assumes that using appropriate Caldecott winners that can meet children’s different educational needs would better result in their emotional, sociocultural, and linguistic development.
In this study, we aimed to compare the mycelial growth of Pleurotus ostreatus after medium supplementation with various amino acids at different concentrations to select the optimal medium nutrient composition for mycelial growth. The mycelial growth of P. ostreatus was investigated after adding four amino acids (tryptophan, threonine, methionine, and lysine) at 0.5% or 1% to the medium.The rate of P. ostreatus mycelial growthwas faster in the potato dextrose agar (PDA) medium supplemented with threonine at 0.5% or 1% than that of the control, whereas it was inhibited by tryptophan treatment. Supplementation of sawdust mediumwith all amino acids, except tryptophan, at 0.5% did not alter the mycelial growth, compared to the controls. However, addition of any amino acid to sawdust medium at a higher concentration (1%) inhibited the mycelial growth. The laccase acitivity of P. ostreatus mycelium cultured in PDA medium was the highest when threonine was added, and the lowest when tryptophane was added, consistent with the results of the mycelial growth. Therefore, the addition of threonine, methionine, or lysine to PDA medium at a concentration of 0.5-1%was effective for increasing the mycelial growth of P. ostreatus; however, it inhibited mycelial growth insawdust medium, suggesting that the effects of amino acids dependedon the medium nutrient composition.
본 연구는 학원강사들이 지각하는 조직지원인식(학원지원, 상사지원, 동료지원), 직무열의(활력, 전념, 몰두), 조직시민 행동(학원지향, 동료지향, 고객지향)에 대한 인식과 개인배경에 따른 차이를 살펴보고, 조직지원인식과 직무열의가 조직 시민행동에 영향을 미치는 요인을 알아보는 것을 목적으로 하였다. 이를 통해 학원 내 조직지원의 수준을 높이고, 학원 강사의 직무열의 및 조직시민행동의 수준을 높이는 방안을 모색함으로써 학원의 경영 안정화 및 교육적 기능 강화에 도 움이 되고자 하였다. 이상의 연구목적을 달성하기 위하여 학원에서 초·중·고등학생들을 지도하는 학원강사들을 대상으로 구글(Google) 설문지를 활용하여 총 357부의 설문지를 회수하였으며, IBM SPSS Statistics 24 활용하여 수집된 자료를 분석하였다. 주요 연구결과는 다음과 같다. 첫째, 학원강사가 지각하는 조직지원인식, 직무열의, 조직시민행동의 수준은 보통이었다. 다만 학원강사의 조직시민행동은 조직지원인식과 직무열의보다 상대적으로 높게 나타났다. 둘째, 개인 배경 에 따른 조직지원인식, 직무열의, 조직시민행동에 대한 인식은 성별, 연령, 근무기간, 소속계열에서는 차이가 없는 반면, 학력, 직급, 지역에 따라 차이가 있었다. 셋째, 직무열의에 영향을 미치는 요인은 조직지원인식의 학원지원, 상사지원, 동 료지원이었고, 조직시민행동에 영향을 미치는 요인은 조직지원인식의 동료지원과 직무열의의 전념, 몰두였다. 결론적으 로 학원강사의 직무열의를 높이기 위해서는 경영자 및 상사가 학원강사들에게 물질적, 정서적 지원을 하여야 하고, 동료 간에 상호이해 증진을 위해 노력하여야 한다. 또한 조직시민행동의 수준을 높이기 위해서는 동료지원이 중요하고, 학원 강사가 직무에 전념하고 몰두할 수 있는 ‘행복한 일터’ 환경의 조성이 요구된다.
미역(Undaria pinnatifida) 포자를 사용한 생태독성 시험법은 연중 상시 이용하기에 어렵다. 미역 의 암배우체는 실험실에서 배양할 수 있기 때문에, 포자의 단점을 보완하고 상시 생태독성 시 험에 사용할 수 있다. 따라서 미역의 암배우체를 생태독성 시험에 활용하기 위해 다양한 환경 조건에 노출된 미역의 암배우체 생존율과 상대성장률의 변화를 분석하였다. 미역 암배우체는 염분(5~40 psu), 온도(5~30℃), pH (2~10), 광량(0~120 μmol photon m-2 s-1)에 노출되었다. 암배 우체의 생존율은 최고 평균값을 기준으로 온도 20℃, 염분 27.5 psu, pH 8, 광량 30 μmol photon m-2 s-1에서 가장 높았다. 상대성장률은 최고 평균값을 기준으로 온도 15℃, 염문 35 psu, pH 9, 광량 60 μmol photon m-2 s-1에서 가장 높았다. 본 연구결과를 통해 미역 암배우체의 생존율과 상대성장률을 활용하여 연안환경을 상시 신속하게 평가하기 위한 효율적인 방법으로 활용이 기대된다.