• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.569-575
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• 1988

Storage stabilities of ramyons fried in palm oil and beef tallow with added antioxidants and their synergists were investigated by comparing the changes in physicochemical parameters and n-hexanal concentrations of oils extracted from ramyons during storage. Ramyons fried in palm oil and beef tallow with added ${\delta}-tocopherol$ $({\delta}-toc)$ showed an enhanced storage stabilities when compared to those fried in the oils with ${\alpha}-tocopherol$ $({\alpha}-toc)$. Ascorbyl palmitate was found to be a better synergist than citric acid for the antioxidant activity of both ${\delta}-toc\;and\;{\alpha}-toc$. Phenolic antioxidants gave a better storage stability than tocopherol when ramyon was fried in beef tallow, while a mixture of BHA and BHT gave an inferior storage stability than${\alpha}-toc$ when ramyon was fried in palm oil. The effectiveness of the antioxidants tested on storage stability of stored ramyon had a close relationship to the n-hexanal concentration. On the other hand, the paramenters such as peroxide value, carbonly value, and conjugated diene concentration showed inconsistency during the course of the storage experiment.

• Bulletin of Food Technology
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• v.8 no.1
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• pp.132-139
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• 1995

이미 조리된 상태의 냉동 즉석 육제품의 수요가 연회부문에서나 소매부문에서 모두 증가될 것으로 전망된다. 이러한 제품들에 있어 warmed-over flavour(WOF)의 발생속도는 종종 그 제품들의 저장수명을 결정하기도 한다. WOF는 소비자들에게 '뒷맛' 또는 산패된 맛으로 인식되는 것으로서, 조리된 육류를 냉장저장할 때 쉽게 발생되며 육류의 산화적 변패와 연관이 되어 있다. 몇가지 시도들이 그러한 WOF의 발생을 지연시키는 데 응용될 수 있다. 이 보문의 목적은 어떻게 하면 WOF의 발생을 지연시킬 수 있는가에 있으며, 산화방지제의 사용이나 가공 조건의 최적화에 그 강조점을 두고 있다.

• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.195-198
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• 2004

실리콘 산화막 위에 구리 확산 방지막으로서 W-N 박막을 $NH_3$ 펄스 플라즈마를 이용한 원자층 증착방법으로 형성하였다. 플라즈마 원자층 증착방법 (PPALD)은 일반적인 원자층 증착방법(ALD)의 성장 기구를 그대로 따라 간다. 그러나 일반적인 ALD 방법에 의해 증착한 W-N 박막에 비해 PPALD 방법으로 증착한 W-N 박막은 F 함유량과 비저항이 감소하였고 열적 안정성에 대한 특성도 향상되었다. 또한 $WF_6$ 가스는 실리콘 산화막과 반응을 하지 않기 때문에 $WF_6$ 가스와 $NH_3$ 가스를 사용해서 ALD 증착방법으로 실리콘 산화막 위에 W-N 박막을 증착하기 어려운 문제점(8,9)을 $NH_3$ 반응종으로 실리콘 산화막 표면을 먼저 변형시켜 $WF_6$ 가스가 산화막과 반응을 할 수 있게 함으로써 ALD 방법으로 W-N 박막을 실리콘 산화막 위에 증착 할 수 있었다.

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.785-791
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• 2014

The antioxidative activities of beverages with water or ethanol extracts from Maegmundong (Liriope platyphylla) were investigated with free amino acid and mineral analysis, as well as saponin, total phenolics and flavonoid determination. Antioxidative activity was evaluated by electron donating ability and ABTS radical scavenging activity. There was only a small difference between water extract beverages and ethanol-extract beverages with respect to their electron donating ability and ABTS radical scavenging activity, although the total saponin, total phenolics and flavonoid were found to be greater in the ethanol extract beverages than in the water extract beverages. Three major free amino acids of the Magemundong beverages with water- or ethanol extract were asparagine (58.30, 60.68 mg%), methionine (15.10, 13.95 mg%, respectively) and proline (12.31, 14.00 mg%, respectively). The most abundant mineral in the Maegmundong beverage with water and ethanol extract was potassium (238.68, 244.32 mg%, respectively).

• Membrane Journal
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• v.33 no.6
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• pp.416-426
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• 2023

In this study, hindered amine-grafted graphene oxide (HA-GO) with antioxidant properties was prepared and incorporated into Nafion-based composite membranes as an effective filler material for polymer electrolyte membrane fuel cell applications. HA-GO was synthesized via a ring-opening reaction between amine groups in 4-amino-2, 2, 6, 6-tetramethyl piperidine and epoxy groups on the surface of GO. Nafion-based composite membranes containing different weight contents of HA-GO were fabricated to compare the polymer electrolyte membrane properties with those of the pure Nafion membrane. The composite membranes with HA-GO were found to have better mechanical properties, chemical stability, and proton conductivity than the pure Nafion membrane. In particular, the conductivity retention behavior confirmed by the decrease in proton conductivity after Fenton's test of the composite membranes was better than that of the pure Nafion membrane due to the incorporation of HA-GO with effective antioxidant properties.

• Tribology and Lubricants
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• v.7 no.2
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• pp.28-35
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• 1991

3원통/링 마모시험기를 사용하여 윤활유 공급하에서 미끄럼 마모시험을 수행하였다. 엔진유에 첨가되는 대표적 첨가제인 ZDDP, 청정제, 분산제의 첨가제 3종과 모델 산호물로서 유성제인 스테아린산을 선택하여, 그 배합유의 마모방지특성을 조사하였다. 청정제 및 분산제 각각의 첨가에 의해 마모방지특성은 향상되었으나, 청정제 및 분산제를 동시에 첨가할 경우 마모방지성능의 향상효과는 없어졌다. 또한, 모델산화물인 스테아린산의 첨가로 인하여 ZDDP의 마모방지작용은 나빠지나, 청정분산제가 그 악영향을 억제하는 작용을 한다.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.283-288
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• 1997

The antioxidant activities of Korean Red Ginseng Extract(RGE) and ${\alpha}-tocopherol$, as reference compound, were tested with HPLC and fluorometry which measure the MDA after reacting an aqueous 1% linoleic acid buffer solution, and LDL(1 mg protein/ml) buffer solution with $H_2O_2{\;}and{\;}FeCl_2$. The generation of conjugated-diene in LDL(0.25 mg protein/ml) was also measured by spectrometry. MDA determination showed the antioxidant effect on linoleic acid oxidation with oxidation inhibition ratio of 71.8% and 76.1%, respectively, by addition of 1000 ppm RGE and 100 ppm ${\alpha}-tocopherol$. LDL(1 mg protein/ml) oxidation was inhibited by 25.2% and 21.2%, respectively, by addition of 200 ppm REG and 100 ppm ${\alpha}-tocopherol$. The generation of conjugated diene in LDL(0.25 mg protein/ml) was also inhibited by 44.2%, by addition of 50 ppm RGE.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.419-424
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• 2015

The objective of this study was to investigate the physicochemical and antioxidant properties of a variety of commonly consumed commercial green tea. Green tea samples with the same commercial name produced at different regions were analyzed. High-grade tea samples showed higher values of lightness (L) and greenness (-a). Additionally, compared to other varieties of teas, high-grade tea samples showed higher levels of catechin, gallocatechin gallate (GCg), epicatechin gallate (ECg), theanine, and methylxanthines and a lower level of epigallocatechin (EGC). The antioxidant activity of green tea was also investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical assays. High-grade teas were observed to have higher antioxidant activities. The results of this study indicate that the catechin content, such as EGCg, GCg, and ECg levels, was found to positively influence the total antioxidant activity of green tea.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.413-418
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• 2015

This study was conducted to analyze the functional component contents and antioxidant activities of Cedrela sinensis extracts hydrolyzed using four different enzymes. The yield of Viscozyme extract was the highest among the samples, and all enzymatic extracts, except for the commercial glucoamylase (AMG) extract, had significantly higher total polyphenol and flavonoids contents compared to the non-enzymatic extract (p<0.05). Viscozyme extract showed the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and $Fe^{2+}$ chelating ability among the samples. All enzymatic extracts showed high>90% 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, and there was no significant difference between the enzymatic and non-enzymatic extracts. The reducing power of the extracts using Shearzyme or Viscozyme was significantly higher than that of the other samples (p<0.05). Therefore, the results indicated that all enzymatic extracts (especially Viscozyme extract), except for the AMG extract, showed high antioxidant activity compared to the non-enzymatic extract. These result suggested that the enzymatic extracts of C. sinensis can be used in functional foods.

• Journal of Food Hygiene and Safety
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• v.36 no.1
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• pp.86-92
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• 2021

In order to utilize edible insect larvae as a functional material, the antioxidant components and activities of Tenebrio molitor larvae extracts were evaluated. The total phenolic content of the extract by ethanol concentration (95%, 70%, 50%, water) of T. molitor larvae powder was the highest in the 50% ethanol extract at 459.23 ± 1.05 mg%, and the total flavonoid content was the highest in the water extract at 19.86 ± 0.69 mg%. The DPPH radical scavenging activity of T. molitor larvae powder extract was the highest in 70% ethanol extract at 82.60 ± 0.00%, followed by water, 50% ethanol, and 95% ethanol extract. The ABTS radical scavenging activity in 50% ethanol and water extract was highest at 97.57 ± 0.16% and 95.33 ± 0.41%, respectively, with no significant difference. Significantly, the reducing power was the highest in water extracts, followed by 50%, 70%, and 95% ethanol extract. The results confirmed the antioxidant components and antioxidant activities of T. molitor larvae have been identified, indicating that it is worth using as a functional material.