Ethyl formate (EF) is a potent fumigant replacing methyl bromide. The use of EF is limited to a quarantine process. Appling EF to agricultural field as a safe insecticide in greenhouse give us valuable benefits including less residual concern. In this regard, residual pattern after EF fumigation in greenhouse should be undertaken. In the previous study, we have established agricultural control concentration of EF to control pests in a greenhouse. EF was fumigated at 5 g m-3 level for 2 h. The concentration of EF inside a greenhouse was analyzed to be 4.1-4.3 g m-3 at 30 min after fumigation. To prepare an analytical method for residues in cucumber crops and soil in the greenhouse, the limit of detection (LOD) of the method was 100 ng g-1 and the limit of quantitation (LOQ) of this method was 300 ng g-1. R2 values of calibration curves for crops and soil were 0.991-0.997. In samples collected immediately after ventilation, EF concentration was determined to be below LOQ level. In addition, EF level was below LOQ in samples collected at 3 h after ventilation except that leaf samples of melon during the flowering period showed a level of 1,068.9 ng g-1. Taken together, these results indicate that EF used in quarantine can be applied to agricultural fields without residual issue as an effective fumigant for insect pest control.

본 연구에서 흰목이버섯의 추출조건별 추출수율과 기능성 성분의 함량을 비교하여 최적 추출조건을 분석하였으며, 모든 분석에서 R²이 0.9331~0.9462로 유의성을 보이는 것을 확인하였다. 각 독립변수에 따른 추출수율과 ergothioneine, β-glucan 성분을 분석한 결과 추출수율은 추출온도와 추출시료농도에 반비례했으며, 추출시간에는 큰 영향이 없었다. Ergothioneine 성분은 온도가 증가할수록 증가하며, 추출시간은 4.33 h가 가장 높았고 시료량에 큰 영향이 없었다. β-glucan 성분은 온도가 증가할수록 감소했으며, 추출시간에 큰 영향이 없었고 시료량이 21.2 mg/mL에서 가장 높았다. 모든 종속변수의 최대 독립변수는 온도 60 o C, 추출시간 4.33 h, 추출시료농도 16.6 mg/mL에서 추출수율 24.9%, ergothioneine 성분함량 66.8 ug/g, β-glucan 성분함량 34.9 g/100 g으로 나타났다.

This study was designed to evaluate the improvement in exercise endurance by Hovenia dulcis fruit hot water extract (HDWE) for the potential application as a functional food material. The effect was based on the evaluation of the forced-swimming capacity and changes in biochemical parameters in mice. Six-week-old mice were classified into four groups based on a randomized block design: the negative control group, the HDWE 50 mg/kg body weight group, the HDWE 200 mg/kg body weight group, and the 1-octacosanol 50 mg/kg body weight group (n=8 mice per group). The swimming exercise time in the HDWE-50 group was increased at 545±43 sec compared to the control group at 263±28 sec. The HDWE-200 fatigue indicators, lactate acid and ammonia content, decreased to 4.99±0.33 mg/mL and 0.63±0.05 mg/mL, respectively. In addition, the content of glycogen in the liver and muscle tended to increase in the group administered HDWE but was not significant. Likewise, the LDH and glucose contents were increased compared to the control group. The muscle damage indicators ALT (52.7±2.6 U/L) and AST (42.5±5.2 U/L) tended to decrease compared to the control group (76.4±10.2 U/L).

에틸포메이트는 살충 효과가 빠르고 환경에 무해하며 특히 인축독성이 낮아 검역용 훈증제로 등록되어 있다. 이러한 에틸포메이트를 이용하여 훈증 챔버 (0.275 m3) 내에서 4종의 농업 해충 (오이총채벌레, 담배가루이, 복숭아혹진딧물, 점박이응애)과 4종의 작물 (참외, 오이, 토마토, 고추) 유묘기를 대상으로 12시간 훈증 처리하여 약효와 약해를 평가하였다. 에틸포메이트 1.5 g/m3의 약량으로 12시간 훈증 했을 때 담배가루이와 복숭아혹진딧물은 93.3% 이상의 높은 살충력를 나타내었으나, 점박이응애는 2.0 g/m3 약량에서도 20% 미만의 낮은 살충력을 나타내었다. 그리고 에틸포메이트의 CT값(농도ⅹ시간)이 훈증 처리 온도 20 ± 1.5℃에서 8.9 g･h/m3 이상일 때 점박이응애를 제외한 나머지 3종의 해충에 대해서 90% 이상의 살충 효과를 얻을 수 있었다. 에틸포메이트 1.5 g/m3의 약량으로 상기 4작물을 12시간 훈증했을 때 약해 증상은 나타나지 않았다. 따라서 에틸포메이트 훈증기술은 시설 내 해충방제를 위한 새로운 방식이 될 수 있으며 관행적인 살충제의 사용을 줄일 수 있을 것으로 생각된다. 그러나 해충의 충태별, 작물의 생육 시기별 에틸포메이트 약효 및 약해에 대한 많은 연구가 이루어져야 할 것으로 생각된다.

Oxidative DNA damage negatively affects humans and the research is currently ongoing to find ways to reduce oxidative stress. Oxidative stress has been identified as a key factor in triggering various diseases. Thus, its alleviation is important for human health. Broussonetia kazinoki (B. kazinoki) has been used in traditional Korean medicine as a dermatological therapy to treat burns, pruritus, and acne. B. kazinoki is generally segregated into peeled root (PR), root bark (RB), peeled stem (PS), and stem bark (SB). To assess these components for their antioxidant activity and protection against DNA damage, their ethyl acetate fractions were examined by 1,1-diphenyl-2-picryl hydrazyl (DPPH) and 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assay. As a result of confirming the expression of factors involved in attenuating DNA damage, the protective effect of SB on oxidative stress suppressed the expression of p-p53 and γ-H2AX. Additionally, the levels of p53 and H2AX mRNA were significantly downregulated. In conclusion, these results indicated that the SB component of B. kazinoki had the potential to be used as an effective natural antioxidant compared to the other parts of the plant.

This study aimed to investigate the various biological activities of Geranium thunbergii such as antimicrobial activity and protective effect against oxidative damage. To evaluate its antioxidant and antimicrobial activities, we first performed methanol extraction; this methanol extract was further partitioned using various solvents. And then, its antioxidant activity was measured using various assays including total phenolic content and protection against oxidative DNA damage, and antimicrobial activities were examined using minimum inhibiting concentration (MIC) test, and paper disc method. In addition, high-performance liquid chromatography was performed to analyze the major chemical components of ethyl acetate fraction. The G. thunbergii fraction with ethyl acetate exhibited higher antioxidant and antimicrobial activities than the other fractions. The results showed that G. thunbergii ethyl acetate fraction at 50 μg/mL had strong DPPH and ABTS radical scavenging activities of 80.88% and 80.12%, respectively. In addition, the ethyl acetate fraction protected DNA from the oxidative damage induced by ferrous ion and hydroxyl radicals and showed high antimicrobial activity with diameter of inhibition zones ranging from 13.33 to 15.67 mm. High-performance liquid chromatography analysis revealed the major phenolic compounds of G. thunbergii to be ellagic acid and gallic acid. These results suggest that G. thunbergii might protect DNA against oxidative stress induced by reactive oxygen species and can be utilized as a natural source of antioxidant and antimicrobial agent in the food industry.