• Preventive Nutrition and Food Science
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• 제22권3호
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• pp.216-222
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• 2017

Antioxidant rich green leafy vegetables including garden spinach leaf, water spinach leaf, Indian spinach leaf, and green leaved amaranth were selected to evaluate the effects of water boiling and oil frying on their total phenolic content (TPC), total flavonoid content (TFC), reducing power (RP), and antioxidant capacity. The results revealed that there was a significant increase in TPC, TFC, and RP in all the selected vegetables indicating the effectiveness of the cooking process on the antioxidant potential of leafy vegetables. Both cooking processes enhanced significantly (P<0.05) the radical scavenging ability, especially the oil fried samples showed the highest values. There is a significant reduction in the vitamin C content in all the vegetables due to boiling and frying except in the Indian spinach leaf. However, the present findings suggest that boiling and frying can be used to enhance the antioxidant ability, by increasing the bioaccessibility of health-promoting constituents from the four vegetables investigated in this study.

• 산업식품공학
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• 제14권4호
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• pp.342-345
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• 2010

The purpose of current study was to examine bioaccessibility of antioxidant activity and total phenolic content in each part of water spinach (Ipomoea aquatic Forsk.). In vitro biomimicking system simulated human digestive fluid was employed in order to measure bioavailable anti-oxidative effect and phenolic content. Antioxidant activity and total phenolic content was measured by using the DPPH method and the Folin-Ciocalteu assay, respectively. Stem of water spinach had a higher DPPH free radical scavenging effect (5.43 mg/mL for $IC_{50}$) than leaf (5.95 mg/mL for $IC_{50}$), while leaf had a greater level of total phenolic content (287.45 ${\mu}g$ GAE/mL) than stem (216.45 ${\mu}g$ GAE/mL). Bioaccessible antioxidant capacity and digestive stability of total phenolic content showed a similar pattern to what found in raw materials. Our result also indicated that total phenolic content was not found to be a major marker for prediction of antioxidant activity. It is plausible that other constituents such as vitamin E and C in water spinach could be contributors for antioxidant activities.

• 공업화학
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• 제31권4호
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• pp.360-367
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• 2020

본 연구에서는 미세플라스틱의 토양 내 축적경로와 분포현황에 대해 살펴보고, 토양시료 내 미세플라스틱 분석기법을 요약 제시하였다. 토양으로부터 미세플라스틱을 분리해내는 밀도차 선별 및 방해물질 제거과정과 정성/정량분석 기법으로써 pyrolysis gas chromatography mass spectrometry, µ-Raman spectrometry, fourier transform infrared spectrometry와 microscope 방법의 기본원리 및 분석의 한계점에 대해 살펴보았다. 미세플라스틱 매개 유해물질(첨가제 및 흡착물질)의 분석을 위한 화학적 추출방법을 인체 경구 섭취경로에 대한 in vitro 생물학적접근성 평가법을 중심으로 조사하였다. 본 연구에서 제시한 토양 중 미세플라스틱 분석기법의 원리를 바탕으로 매질상태, 오염수준 및 시료수량 등을 고려한 합리적인 분석기법의 선정이 가능하리라 기대된다.

• Advances in environmental research
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• 제1권1호
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• pp.15-35
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• 2012

Mercury (Hg) is a global environmental pollutant that has been the cause of many public concerns. One particular concern about Hg in aquatic systems is its trophic transfer and biomagnification in food chains. For example, the Hg concentration increases with the increase of food chain level. Fish at the top of food chain can accumulate high concentrations of Hg (especially the toxic form, methylmercury, MeHg), which is then transferred to humans through seafood consumption. Various biological and physiochemical conditions can significantly affect the bioaccumulation of Hg-including both its inorganic (Hg(II)) and organic (MeHg) forms-in fish. There have been numerous measurements of Hg concentrations in marine and freshwater fish worldwide. Many of these studies have attempted to identify the processes leading to variations of Hg concentrations in fish species from different habitats. The development of a biokinetic model over the past decade has helped improve our understanding of the mechanisms underlying the bioaccumulation processes of Hg in aquatic animals. In this review, I will discuss how the biokinetic modeling approach can be used to reveal the interesting biodynamics of Hg in fish, such as the trophic transfer and exposure route of Hg(II) and MeHg, as well as growth enrichment (the increases in Hg concentration with fish size) and biomass dilution (the decreases in Hg concentration with increasing phytoplankton biomass). I will also discuss the relevance of studying the subcellular fates of Hg to predict the Hg bioaccessibility and detoxification in fish. Future challenges will be to understand the inter- and intra-species differences in Hg accumulation and the management/mitigation of Hg pollution in both marine and freshwater fish based on our knowledge of Hg biodynamics.

• 한국식품과학회지
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• 제47권2호
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• pp.184-190
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• 2015

양배추를 각기 다른 방법(blanching, steaming, microwaving)으로 가열하면서 열처리 시간에 따른 glucosinolates와 SMM의 함량 변화 및 항산화 활성을 양배추 에탄올 추출물의 농도별로 측정하였다. 신선한 양배추 추출물에는 glucoraphanin, sinigrin, 4-methoxyglucobrassicin 및 glucobrassicin의 4종의 glucosinolates를 HPLC 분석방법으로 확인하였다. 양배추는 SMM 함량이 건조중량 100 g 당 192.85 mg으로 다른 십자화과 채소들에 비해 풍부하였다. 끓는 물에 데치는 조리법에 비해 스팀을 이용하여 찌거나 전자레인지로 가열하였을 때 glucosinolates와 SMM 함량이 높게 나타났으며 이는 다량의 물을 사용하여 끓이는 경우, 수용성이 강한 이들 물질들이 조리수로 용출되기 때문으로 사료된다. 소량의 물을 붓고 찌거나 전자레인지로 가열하는 경우는 glucosinolates 나 SMM이 조리수로 용출되는 것을 최소화하는 동시에 활성물질들이 열처리를 하는 동안 양배추 조직으로부터 분리되어 표면으로 노출되었기 때문으로 해석된다. DPPH와 ABTS 라디칼 소거능력을 통해 양배추 에탄올 추출물의 항산화 활성을 측정한 결과, 가열시간이 길어질수록 항산화 성분이 파괴되어 신선한 양배추에 비해 항산화 활성이 감소하는 것을 확인하였다. 따라서 양배추를 포함한 십자화과 채소의 주요 생리활성 물질인 glucosinolates나 SMM의 파괴를 최소화하기 위해서는 가열 방법과 가열시간을 적절히 선택하는 것이 중요하며, 가급적이면 장시간 동안 물에 끓이는 방법보다는 스팀을 이용하여 찌거나 전자레인지를 이용한 가열방법을 선택하는 것이 바람직할 것으로 사료된다.