• Journal of Ginseng Research
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• 제19권3호
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• pp.244-248
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• 1995

Water-soluble browning pigments were artily purified from Korean red ginseng through the several procedures such as fractionation by n-butanol, precipitation by ethanol, dialysis and gel filtration. At least four kinds of water-soluble browning pigment were separated from each other, two kinds of low-molecular-weight and two kinds of high-molecular-weight pigments.

• Journal of Ginseng Research
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• 제19권3호
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• pp.249-253
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• 1995

In the browning reaction of Korean ginseng, it appears that enzymatic and non-enzymatic browning reaction occurred in the initial stage of heating fresh ginseng at low temperature, and then non-enzymatic browning reaction followed in the drying period after heating. Activation energy of the browning reaction for red ginseng was about 9.0 kcal/mol. Browning reaction of red ginseng was accede- rated with an increase in steaming time, and a great extent of browning reaction occurred between 60-90 min of steaming at 10$0^{\circ}C$. Browning pigments of red ginseng were mostly water soluble subset.

• 한국수산과학회지
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• 제6권1_2호
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• pp.37-43
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• 1973

In this paper, non-enzymatic browning reactions as a factor of self stability of boiled and dried anchovy were studied to discuss the effect of water activity to the discoloring reaction and the preservative moisture content. The development of rancidity of the fish meat was also mentioned since the fish is fatty and the lipid oxidation is a functional deteriorative reaction. Fresh anchovies were boiled in $10\%$ salt solution immediately after the catch, sun dried, and stored at room temperature ($20^{\circ}C$) for two months in humidistat chambers maintaining different levels of water activity as described in Table 1. The pigments formed by non-enzymatic browning reations were extracted in two fractions, those were chloroform-methanol soluble and water dialyzed fraction, and analyzed spectrophotometrically at the wavelength of 460 nm. These two fractions were considered, respectively to be the brown pigments formed by lipid oxidation reactions for the formler and for the latter, to be the pigments developed by sugar-amino or Maillard reaction. The oxidation of lipid in anchovy meat during the storage was measured as the changes in Peroxide value and the color development of thiobarbituric acid reaction. It is summarized from the results that the rate of both reactions, lipid oxidation and browning, was affected by water activity levels. In regard to the changes in peroxide and TBA value during the storage, the propagation of lipid oxidation was obviously accelerated at lower humidities whereas the development of browning progressed at the higher. These two reactions occurring simultaneously and contrary in activity resulted in that the rate of deterioration occurring oxidatively or by browning, was the minimum at the water activity of 0.32-0.45 which were $7-9\%$ as moisture content and slightly higher value than that of monolayer (Aw=0.21, $5.11\%$ as moisture content). It is also noted that the lipid oxidative browning was presumed to dominate sugar-amino reactions so that the rate of browning of the meat was ultimately depended on the development of rancidity although sugar-amino reactions initiated earlier than the other at the first ten days of storage, particulary at higher humidity. At the lower humidity sugar-amino reactions were occurred gradually but lower levels in color development in contrast to the consistent increase in lipid oxidative browning.

• 한국수산과학회지
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• 제20권4호
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• pp.273-281
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• 1987

In this work the antioxidant effects of browning reaction products prepared by xylose-tryrtophan reaction system were discussed. The antioxygenic brown pigments were separated by solvent extraction, and column chromatography and isolated by gel filteration. The functional groups of the brown pigments which had antioxidant activity were examined. The brown pigments extracted with methanol showed antioxidant effect and were fractionated in 5portions on DEAE-cellulose column. The elutes with methanol: acetic acid(10:30 v/v sol n(A), methanol: chloroform(95:5 v/v) sol n(C), and chloroform: acetic acid(10:30 v/v) sol n(E) only showed antioxidant activity and their compositions were 22.43, 21.51 and $34.43\%$ respectively. When each fraction on DEAE-cellulose column was reseparated on Sephadex LH-20 column, 2 fractions were obtained from portion A and C respectively. Molecular weights of A, C and E fraction of brown pigments were from 2,600 to 3,700. By elucidation of IR spectra, the pigment fractions which showed a strong antioxidant activity were tearing the indole group. It is suggested that the antioxidant function of the brown pigment is due to hydroxy and amino group. A higher activity of the brown pigment fraction E might be attributed to carboxylic acid or carboxylic ester compounds.

• Food Science and Biotechnology
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• 제18권3호
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• pp.682-688
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• 2009

Changes in lipophillic pigments concentration and its relation to color of fresh green tea liquor during heat treatment were studied. The results showed liquor greenness decreased markedly with extension of incubation time at $55^{\circ}C$, while the brightness and yellowness changed a little. Significant increase in 'a' and 'b' values of tea liquor was observed at $95^{\circ}C$. Color change of liquor at $55^{\circ}C$ was accompanied by a decrease in the level of chlorophylls, lutein and neoxanthin, and an increase in the pheophytins and ${\beta}-carotene$ levels. However, all pigments except ${\beta}-carotene$ decreased with time extension at $95^{\circ}C$. Significant correlation was found between pigments and color difference index. The browning of fresh green tea liquor was attributed to vicissitudes of lipophillic pigments during heat treatment, especially to the change of chlorophylls/pheophytins ratio. Result also showed addition of $Zn^{2+}$ at 1.6 ${\mu}mol/L$ could partially alleviate the decrease in greenness during heat treatment.

• Journal of Ginseng Research
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• 제5권2호
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• pp.122-131
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• 1981

An aqueous extract s of fresh ginseng roots was heated at loot for 64 hrs. and the changes of color intensity, pH and the amount of free sugars and amino acids during the various intervals of the heating time were investigated. Color intensity and absorbance of the solution at 490nm were increased in proportion to the length of the heating time. Most of brown pigments produced during the treatment were water soluble, and pH 5.1 at initial stage of the solution, was slightly decreased at the final stages of the reaction. Sucrose, glucose and fructose were major free sugars in ginseng roots, and the amounts of sucrose was over 90 % of total free sugars. Sucrose. was largely decreased approximately 50%, by 64 hrs of the treatment, whereas sharp increase in the amount of glucose and fructose was observed during the reaction in the solution. The observed increase in reducing sugars, glucose and fructose was presumed due to hydrolysis of sucrose. Evidently, glucose and fructose were not important factor to control the browning reaction of the solution. Most of free amino acids and peptides except alanine and isoleucine especially arginine, serine and threonine, were sharply decreased up to 40 : 50% of the original concentration within 2 hrs. Accordingly, the content of free amino acids and peptides seems to be extremely important factor to control the browning reaction in ginseng. A free amino acid, presumed to be nor-leucine, was found in fresh ginseng root on the basis of re mention on liquid chromatography. Kinetic analysis of the browning reaction indicated a pseudo second order with respect to amino acid concentration at the initial stage.

• ALGAE
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• 제36권3호
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• pp.195-206
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• 2021

Increasing inputs of dissolved organic matter (DOM) to northern lakes is resulting in 'lake browning.' Lake browning profoundly affects phytoplankton community composition by modifying two important environmental drivers-light and nutrients. The impact of increased DOM on native isolates of red and green-pigmented cyanobacteria identified as Pseudanabaena, which emerged from a Dolichospermum bloom (Dickson Lake, Algonquin Provincial Park, Ontario, Canada) in 2015, were examined under controlled laboratory conditions. The genomes were sequenced to identify phylogenetic relatedness and physiological similarities, and the physical and chemical effects of increased DOM on cellular performance and competitiveness were assessed. Our study findings were that the isolated red and green phenotypes are two distinct species belonging to the genus Pseudanabaena; that both isolates remained physiologically unaffected when grown independently under defined DOM regimes; and that neither red nor green phenotype achieved a competitive advantage when grown together under defined DOM regimes. While photosynthetic pigment diversity among phytoplankton offers niche-differentiation opportunities, the results of this study illustrate the coexistence of two distinct photosynthetic pigment phenotypes under increasing DOM conditions.

• Journal of Ginseng Research
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• 제30권1호
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• pp.41-48
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• 2006

우리나라의 건강기능식품법에서는 인삼 또는 홍삼의 기능성이 자양강장, 면역증진 및 원기회복으로 한정되어 있다. 지금까지 홍삼에 함유된 갈변물질과 산성다당체에 대해서 많은 연구가 수행되었는데, 갈변물질은 항산화 활성과 면역증진기능, 그리고 산성다당체는 소화기관암의 증상개선, 면역기능 증진, 혈압개선, 혈액응고방지, 조혈기능, 알콜해독(간기능 회복, 고지혈 개선 등) 등의 효능이 우수하다고 보고되었다. 이러한 관점에서 현재 인삼과 홍삼의 3가지 기능성외에 항산화활성이라든지 그 외 더 많은 기능성을 추가할 필요성이 있으며, 또 홍삼에 함유되어 있는 활성성분을 적극적으로 이용하여 기준규격형제품은 물론이고 질병위험감소에 대해서 기능성을 표시할 수 있는 개별인정형 제품이나 나아가서는 일반 또는 전문의약품으로 개발하여 홍삼의 이용 가능성을 극대화시키고 국제적으로 경쟁력이 있는 한국인삼으로 그 위상을 제고시켜야 한다고 생각한다.

• 한국식품과학회지
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• 제15권3호
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• pp.287-294
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• 1983

3가지 다른 조건하에서 제조된 압출보리와 생보리를 0.31 및 0.71의 수분활성과 $25^{\circ}C$ 및 $40^{\circ}C$의 온도에서 각각 4개월 저장하면서 색도, 갈색화지수, 가용성 단백질, 환원당 및 유효성 리진의 변화에 대한 수분활성과 온도의 영향에 대하여 연구하였다. 저장기간의 경과와 함께 수분활성과 온도가 증가함에 따라 모든 시료에서 백색도의 손실이 증가하였다. 생보리는 압출보리보다 저장중 갈색화 지수의 증가가 심하였고, 설탕을 첨가하여 제조한 압출보리는 다른 압출보리보다 저장중 갈색화가 적었다. 수분활성과 온도가 증가함에 따라 모든 시료중의 환원당, 가용성 단백질 및 유효성 리진의 함량이 감소하였으며, 이와같은 결과는 저장중 Maillard반응에 의한 것임을 알았다.

• 한국식품영양과학회지
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• 제18권2호
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• pp.143-152
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• 1989

당이나 단백질등의 식품성분이 지질의 산화와 갈변에 어떤 영향을 미치는가를 알아보기 위하여 각종 식품성분에 조기유, 대두유 및 난황유를 각각 9 : 1의 비율로 혼합하여 건계의 실험구를 조성하고 건계에서의 실험결과 지질산화가 촉진되었던 starch구와 억제되었던 casein구에 각각 물을 20% 첨가하여 습계의 실험구를 조성하여 $40{\pm}1^{\circ}C$보존중의 과산화물가, 카아보닐가 및 갈변도의 변화를 조사한 결과는 다음과 같다. 건계에서의 지질산화와 갈변은 조기유 혼합구의 경우는 대두유와 난황유 혼합구에 비해 과산화물가, 카아보닐가 및 갈변도가 월등히 높았다. 식품성분별로는 glucose, sucrose 및 starch구에서 높게 나타났고 cellulose, albumin 및 casein 구에서는 낮게 나타났다. 대두유 혼합구에서는 전 구분 공히 과산화물가가 낮았으며 카아보닐가와 갈변도는 glucose, sucrose 및 starch 구에서는 높게 나타났고 albumin과 casein구에서는 낮게 나타났다. 난황유 혼합구에서는 과산화물가가 대두유 혼합구에서보다 낮았으며 특히 albumn과 casein구는 보존9주까지 과산화물가가 측정되지 않았다. 카아보닐가와 갈변도는 대두유와 동일한 경향이었다. 습계에서의 지질산화와 갈변은 각 지질을 starch에 혼합시킨 경우 조기유 혼합구에서는 과산화물가와 카아보닐가가 건계에서 보다 낮았으며 난황유 및 대두유 혼합구에서는 높은 경향을 나타내었다. 갈변도는 건계에서와 비슷한 값을 나타내었다. 각 지질을 casein에 혼합시킨 경우 과산화물가와 카아보닐가는 각 지질 공히 건계에서보다 낮았으나 갈변도는 오히려 높은 값을 나타내었다. 이상의 실험결과에서 지질의 산화와 갈변도와의 상관관계를 검토해 본 결과 갈변반응은 건계에서보다 습계에서 잘 일어나며 지질의 산화정도가 낮은 식품계에서 생성된 갈변반응물질은 지질의 산화에 억제효과를 나타내나 지질의 산화가 격심한 식품계에서는 효력을 발휘하지 못하거나 상승효과를 나타내는 것으로 판단되었다.