본 연구는 어린이집 급식설비 손잡이의 식중독 세균 오 염도를 측정하고, 분리 균주의 독소 유전자와 항생제 내 성을 분석하여 급식설비 손잡이에 의한 집단식중독을 예 방을 위한 과학적 기반을 마련하고자 하였다. 실험 대상 은 전라남도 일부 지역 어린이집 101곳의 냉장고, 냉동고, 자외선 살균기 손잡이, 총 303개를 대상으로 하였다. 어린 이집 냉장고, 냉동고 손잡이에서 B. cereus 4 균주(1.3%) 가 검출되었고 어린이집 냉장고 손잡이에서 S. aureus 2 균주(0.7%)가 검출되었다. B. cereus와 S. aureus의 독소유 전자를 분석한 결과 B. cereus 4개 균주 모두에서 nheA, nheB, nheC, entFM, cytK가 검출되었으나, S. aureus의 2 개 균주의 경우 모두 sea, seb, sec, sed, see, seg, seh, sei, sej 독소유전자가 불검출되었다. B. cereus에서 설사를 유 발하는 장독소가 검출되어 B. cereus에 의한 식중독 발생 가능성이 상존하는 것으로 판단되었다. B. cereus와 S. aureus의 항생제 감수성을 실험한 결과 B. cereus 4 균주 에서 AM, FEP 등 β-lactam계 항생제에 내성을 나타내었 고 S. aureus 균주 모두 AM, P 항생제에 내성을 나타내 었다. S. aureus 균주는 OX 항생제에 각각 중간 내성 1 균주와 감수성 1 균주를 나타내었으나 MRSA는 검출되지 않았다. 이러한 결과를 종합하여 볼 때 어린이집 급식설 비 손잡이의 교차오염으로 인한 식중독 발생을 예방하기 위해 급식설비 손잡이에 대한 주기적인 살균 등 위생관리 방안을 강화해야할 것으로 판단되었다.

박새는 도시생태계 내 환경변화를 측정할 수 있는 생물지표종이자 대표적인 식충성 조류로 건전성 유지와 같은 중요한 역할을 맡고 있다. 연구자들은 박새과 조류의 번식생태 파악을 위해 인공새집 조사방법을 활용하고 있으나, 공간적･시간적 한계로 거시적 관점의 연구를 진행하기에는 어려움이 있다. 본 연구는 전문가 중심으로 수행된 기존 인공새집 모니터링이 갖는 한계를 벗어나고자 시민참여 인공새집 모니터링 프로젝트를 설계하였다. ‘수원시 앞마당 조류 모니터링단’은 시민조사원 들의 자발적인 참여를 통해 경기도 수원시 내 녹지공간에 인공새집을 설치하고 박새과 조류의 번식생태를 관찰하는 프로젝트이 다. 2021년 2월 9일부터 2월 22일까지 온라인 설문조사를 통해 참가자를 모집하였고, 시민조사원은 2021년 2월 23일부터 8월 31일까지 인공새집 설치부터 관찰까지 직접 수행하였다. 비전문가인 시민조사원들의 진입장벽을 낮추고 일관된 데이터를 수집하기 위해 모니터링 과정 전반에 대한 온라인 교육을 수행하였고 모바일 애플리케이션을 이용하여 인공새집 관찰기록을 수집하였다. 시민참여 인공새집 모니터링 프로젝트에는 98명의 시민조사원이 참여하였고 배포된 206개의 인공새집 중 175(84.95%)개가 수원시 내 녹지공간에 설치되었다. 설치된 인공새집 중 위치 좌표 생성 오류가 발생한 2건을 제외한 173(83.98%)개를 대상으로 시민과학 프로젝트 결과를 확인했다. 시민조사원으로부터 수집한 인공새집 관찰기록은 총 987회 이며, 최솟값은 1회, 최댓값은 26회, 평균은 5.71±4.37회로 나타났다. 월별 인공새집 관찰 횟수는 2월 70회(7.09%), 3월 444회(44.98%), 4월 284회(28.77%), 5월 133회(13.48%), 6월 46회(4.66%), 7월 6회(0.61%), 8월 4회(0.41%)로 조사되었 다. 설치된 173개의 인공새집 중 57개(32.95%)에서 조류의 이용을 관찰할 수 있었고 박새 12개소(21.05%), 곤줄박이 7개소 (12.28%), 미동정 조류 38개소(66.67%)로 확인되었다. 본 연구는 박새과 조류의 번식생태를 조사방법으로 활용되는 인공새집 모니터링에 시민의 참여 가능성을 처음으로 검토한 연구로 향후 시민과학을 접목한 생태모니터링 설계의 기초자료로 활용될 수 있을 것으로 판단된다.

To confirm the applicability of crab apple, the composition and content of amino acids and minerals with ‘Fuji’ apple were measured. Apple and crab apple were extracted with water, 70% and 100% ethanol, respectively. The contents of polyphenols, flavonoids, and ascorbic acid, antioxidant activities of these extracts were measured. The amino acid composition of apples comprised a total of 17 amino acids. The total amino acid contents of apple and crab apple were 2,050.45 mg/kg and 900.05 mg/kg, respectively. For minerals, the total mineral content of apple and crab apple were 489.14 mg%, 529.77 mg%, respectively. The contents of polyphenols, flavonoids, and ascorbic acid of apple and crab apple extracts were highest in 70% ethanol extracts. The content of polyphenols, the crab apple extract, showed a generally higher content than the apple extract. The content of flavonoids, apple and crab apple extracts revealed no difference between extracts. The content of ascorbic acid, apple extract showed a generally higher content than the crab apple extract, but there was no significant difference between extracts. In the case of DPPH and ABTS radical scavenging abilities, 70% ethanol extract showed the highest antioxidant activity, and crab apple showed higher activity than apple extracts.

In this study, we compared the microbial reduction effects of drying, hot water, and microwave sterilization in scourers and dishcloths to suggest a most suitable sterilization method. Three scourer types (silver, copper, and mesh) were used, and three dishcloth types (silver, bamboo, and cotton) were used. Drying time dependent reduction in Escherichia coli was high in silver and copper scourers, but minimal bacterial reduction was obtained against Bacillus cereus in all scourers and dishcloths. In scourers, E. coli was not detected after ≥30 s of hot water sterilization at 77oC, and B. cereus was not detected after ≥60 s of hot water sterilization at 100oC. In dishcloths, E. coli was not detected after hot water sterilization at 77oC for ≥30 s, but B. cereus was detected after hot water sterilization at 100oC for ≥60 s. In scourers, E. coli was not detected after microwave sterilization at 700 W for 3 min, but B. cereus was detected. In dishcloths, E. coli was not detected after microwave sterilization with 700 W for ≥1 min, but B. cereus was detected in the cotton dishcloth even after sterilization for 3 min. In conclusion, the use of antimicrobial scourers (silver and copper) and dishcloths (silver and bamboo) are not sufficient to reduce the microbial contamination. The guideline provided by the Ministry of Food and Drug Safety suggesting dishcloth sterilization via hot water at 100oC for 30 s was also found to be insufficient. Based on our research, we suggest that the most effective methods of microbial management are submerging scourers in hot water at 100oC for ≥1 min, and sterilizing dishcloths for ≥3 min using a 700 W microwave.

To increase the utilization of Centella asiatica (CA), enzymes such as cellulase and pectinase were added and the physicochemical properties of the treated CA were analyzed. In addition, apple-CA jam was prepared using the enzyme-treated CA, which had the best antioxidant properties, and the physicochemical and sensory qualities of the jam were measured. There was a high content of ascorbic acid, polyphenols, flavonoids, reducing sugar, amino acid, minerals and DPPH radical scavenging activity in the enzyme-treated group. The antioxidant component and activity in the jam prepared by adding enzyme-treated CA increased with an increase in the amount of enzyme-treated CA. In the soluble solids, the higher the amount of enzyme-treated CA, the higher the value, but there was no significant difference in pH. The sensory evaluation of the jam, in particular the taste, showed that the highest preference was observed when the enzyme-treated CA was added in the range of 5.0~6.7%, and the control group showed the lowest preference. There was no significant difference in flavor and spreadability among the treatment groups, however, the control group showed the highest color preference. In the overall acceptability, when 5.0% of enzyme-treated CA was added, the highest acceptability was shown.

Centella asiatica (CA) is a vegetable that has been used for medicinal purposes for a long time, but it is not well known in Korea. In this study, the approximate analysis, physicochemical properties, free sugars, free amino acids and minerals of native and improved CA cultivated in Chungju area were measured. And the antioxidant contents and activities of CA solvent extracts were measured. There was no significant difference between native and improved species. As for the characteristics of CA, it was confirmed that the improved species had a large weight, size and a tough texture. Glucose was detected in native CA, fructose, glucose and sucrose were detected in improved species. A total of 15 free amino acids were detected and the content was slightly higher in improved species than in native species. The mineral content in CA was slightly higher in the improved species, and the detected minerals were Na, P, Ca, K, Mg and Fe. Polyphenols, ascorbic acid and flavonoids in each extraction solvent (water, 70% and 100% ethanol) were all higher in the improved species than in native species. And it was found that the antioxidant activities of ethanol extracts were higher than that of water.

Cr-Si based alloys are not only excellent in corrosion resistance at high temperatures, but also have good wear resistance due to the formation of Cr3Si phase, therefore they are promising as metallic coating materials. Aluminum is often added to Cr-Si alloys to improve the oxidation resistance through which stable alumina surface film is formed. On the other hand, due to the addition of aluminum, various Al-containing phases may be formed and may negatively affect the heat resistance of the Cr-Si-Al alloys, so detailed investigation is required. In this study, two Cr-Si-Al alloys (high-Si & high-Al) were prepared in the form of cast ingots through a vacuum arc melting process and the microstructural changes after high temperature heating process were investigated. In the case of the cast high-Si alloy, a considerable amount of Cr3Si phase was formed, and its hardness was significantly higher than that of the cast high-Al alloy. Also, Al-rich phases (with the high Al/ Cr ratio) were not found much compared to the high-Al alloy. Meanwhile, it was observed that the amount of the Al-rich phases reduced by the annealing heat treatment for both alloys. In the case of the high temperature heating at 1,400 oC, no significant microstructural change was observed in the high Si alloy, but a little more coarse and segregated AlCr phases were found in the high Al alloy compared to the cast state.

To analyze the quality characteristics of soybean (Glycine max), the approximate analysis, physical properties, mineral and free sugar content of domestic soybean cultivars were analyzed. The moisture content was about 9.15~11.84%. The fat content of Cheonga, Taekwang, and Jinpung cultivars were 17.93~18.37%, which was significantly higher than that of others. Protein content of Cheonga and Seonyu were 36.15~36.70%, significantly higher than that of others. As for the weight and shape of soybeans, the Daewon was the largest allele, and the seed cover ratio was the highest in the Seonyu. In terms of water absorption rate, the Seonyu showed the highest absorption rate at 246.19%, and the Daewon showed the lowest absorption rate. Soaked soybeans had a hardness of 2.80~4.73 kg/cm2, which did not show low hardness in the sample with high moisture absorption. The grinded soybeans showed higher lightness and yellowness values than the raw soybeans, and the redness was decreased. Soybean minerals contained high K, P, Mg, and Ca content. Overall, The Taekwang contained more minerals than others. Stachyose, sucrose, glucose and fructose were detected as free sugars in soybeans. The total free sugar content of Taekwang was the lowest at 3.47%, and the Cheonga (6.80%) was the highest.

The purpose of current study is to investigate the beneficial effect of enzyme (Alcalase) hydrolysates of silk protein in rat. Alcalase-treated silk protein hydrolysate (ATSH) itself did not show any cytotoxicity on the hepatic tissues and blood biochemistry, similar to the normal condition. ATSH played a protective role in tert-butyl hydroperoxide (t-BHP)-induced hepatotoxicity and liver damage. The values of AST (aspartate aminotransferase) and ALT (alanine aminotransferase), which are the indicators of the liver function, were effectively alleviated with the ATSH treatment in a dose dependent manner. The level of Lactate dehydrogenase (LDH) and Malondialdehyde (MDA), which were increased with t-BHP treatment, were significantly reduced by ATSH. High dose of ATSH (2 g/kg) reduced the t-BHP-induced LDH release by 48%. Antioxidant and antioxidant enzymes in liver cells were significantly increased by ATSH treatment in their level and activities. ATSH (2 g/kg) increased glutathione (GSH), an intracelluar antioxidant, by 2.5-fold compared with the t-BHP treated group. The activities of glutathione-s-transferase (GST), superoxide dismutase (SOD), and catalase were also elevated by 38%, 60%, and 45%, respectively, with ATSH (2 g/kg) treatment. The antioxidative effect of ATSH was recapitulated to the protection from t-BHP induced liver damages in hematoxylin and eosin (H&E) staining. Thus, ATSH might be used as a hepatoprotective agent.