• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.403-408
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• 2013

The composition and antioxidant activity of three kinds of dried laver were compared (ondolgim, bandolgim, and paraegim). Dolgim was high in protein (>35%), carbohydrates (>41%), and minerals (>7.5%). Lipid content in dolgim was very low (<1%); eicosapentaenoic acid was the most abundant fatty acid. There were higher levels of carotenoids than phycobilin in dolgim, and chlorophyll among pigments was present at the least amount. Porphyran content was high (>110 g/kg), while tocopherol content was very low (<12.0 mg/kg). Ondolgim had the lowest levels of carotenoids, phycobilin, and chlorophyll, however, polyphenol content was higher in ondolgim. The antioxidant activity was the same among the three kinds of dolgim, and both water and a 20% ethanol extract of dolgim showed higher antioxidant activity than did a 100% ethanol extract. The results suggested that dried laver dolgim was a good food and that all varieties provided both food and health functionality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.802-807
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• 2022

We investigated the physical properties and color values of surimi mixtures with added natural red pigments from laver Pyropia yezoensis. After adding the natural red pigment from seaweed extract to surimi, the hardness, gumminess, and chewiness of the surimi decreased compared to the negative controls. The L^* color value was lower for the surimi mixture than the negative controls, but the a^* and b^* color values were higher. After cold storage for 7 days, the unheated surimi mixture showed increased firmness, but decreased adhesiveness. Moreover, the gumminess and chewiness of the surimi mixture stored after heating were increased compared to the pre-storage values. These results indicate that seaweed extract pigments may be used as additives for surimi, to increase the color preference, with little effect on the physical properties.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.260-263
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• 2006

In this study, we investigated the antimicrobial effect of 14 different herbal petal extracts on various foodborne and food spoilage bacteria. Herbal petal extracts were prepared with 70% ethanol followed by sequential hexane, chloroform, ethyl acetate, n-butanol, and water fractionation. Antimicrobial activity was highest in the ethanol fraction from roselle (Hibiscus sabdariffa L.) petals as determined by the paper disc method. The roselle ethanol extract retarded the growth of food spoilage bacteria in kimbap (rice rolled in dried laver). Foodborne microorganisms (e.g. Bacillus cereus and Clostridium perfringens), on the other hand, were most efficiently inhibited by the ethyl acetate fraction of the roselle petal extract as determined by growth inhibition curves. Our study shows that roselle petals harbor antimicrobial activity against foodborne and food spoilage microorganisms. The critical ingredient is highly enriched in the ethyl acetate fraction of the extract.

• Food Science and Preservation
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• v.21 no.1
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• pp.62-68
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• 2014

This study was performed in order to investigate the functional components of 5 kinds of marine algae. We have collected 5 samples of marine algae, such as the sea mustard (Undaria pinnatifida), sea tangle (Laminaria iaponice), sea weed fusiforme (Hizikia fusiforme), green laver (Entetomotpha), laver (Phophyratenera), which have been harvested in Jeollanam-do. In order to examine the functional effects, 5 kinds of marine algae were extracted with hot water ($80^{\circ}C$, 4 hr), ethanol and methanol (R.T., 4 hr), and subcritical water extract (SWE, 3 MPa, $90^{\circ}C$, $150^{\circ}C$, $210^{\circ}C$). A higher yield of extract was obtained through SWE method (3 MPa, $210^{\circ}C$) in all of the samples obtained. The highest total sugar content was 427.4 mg/g in green laver extracted with SWE (3 MPa, $210^{\circ}C$). The content of the SWE total phenolic compounds was higher than that of the water and solvent (methanol, ethanol) extracts. The anti-oxidative activities of the extracts from 5 kinds of marine algae were examined through the DPPH radical scavenging activity test. The SWE (3 MPa, $150^{\circ}C$ and $210^{\circ}C$) of the marine algae was the highest among all of the extracts. As per the results, the SWE of the marine algae contained more functional components and it had a higher antioxidant activity than those of the other extracts. The $IC_{50}$ value of tyrosinase in seaweed fusiforme and laver were higher than those of the other samples. These results strongly support the possible use of marine algae as functional materials.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.1
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• pp.108-117
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• 2017

Laver, Porphyra, is distinctive for its high content of proteins and polysaccharides such as porphyran and hemicellulose. The chemical properties of the polysaccharides extracted with different extraction methods such as hot water, dilute acid(pH 4.0) or alkali solution(2N NaOH) were examined to investigate the suitable extraction conditions for porphyran and hemicellulose from laver. For porphyran extraction, dilute acid solution was more preferable to hot water and alkali solution because of its higher 3,6-anhydrogalactose content and lower protein content. However, alkali solution was more suitable to extract the hemicellulose because of higher mannose content indicating the extraction of mannan. To decrease contamination of the polysaccharides with protein, the dried lavers were pretreated with enzymes (Protamex, Flavourzyme, Alcalase, Viscozyme) before hot water extraction. All enzyme pretreatments increased the yield of polysaccharides by compared with control (enzyme unpretreated) and Flavourzyme pretreatment was most effective to decrease protein contamination in the polysaccharide. All viscosities of porphyran solutions pretreated by enzymes were lower compared to the control porphyran solution and showed pseudoplastic behavior with yield stress. In case of alkali extraction of residues obtained after enzyme hydrolysis and hot water extraction, protease pretreatment increased the mannose contents in the polysaccharide while the xylose content was increased by Viscozyme pretreatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.826-833
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• 2008

The effects of porphyran-chungkookjang on cytotoxicity of human normal cell line (BJ) and human cancer cell lines (AGS and HT-29) were examined. Porphyran, which was prepared from laver (Porphyra yezoensis), decreased the viability of the cancer cells, however, it did not affect the viability of normal cells. Porphyranchungkookjang was prepared by the addition of 5% (w/w) porphyran into chungkookjang which was fermented by starter, Bacillus subtilis DJI. The cytotoxicity effects of the chungkookjang and porphyran-chungkookjang were evaluated with MTT assay. The methanol and the water extract of porphyran-chungkookjang at 1.0 mg/mL showed $23{\sim}38%$ decreases in proliferation of cancer cells (AGS and HT-29). However, the methanol and the water extracts of porphyran-chungkookjang did not inhibit the growth of normal cell. Moreover, the methanol extract of porphryan-chungkookjang at 1.0 mg/mL showed $1.2{\sim}1.5$ fold higher anticancer effects than that of the chungkookjang.

• Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.158-168
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• 2023

The global output of Pyropia yezoensis (dried seaweed or laver, also called 'Gim' in Korea) has been reduced over the half-decade due to the wide spread of red rot disease, a serious algal disease affecting P. yezoensis. Recently, Gold 1 (G1), which is a resistant strain of P. yezoensis to red rot disease, was developed and commercialized in South Korea, yet its physiological activity has not been investigated. In this study, a comparative study was performed on G1 and commercially available strain of P. yezoensis (CP) for their antioxidative activities. Aqueous extract of G1 showed more marked 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity compared to that of CP. In 293T cells, antioxidant activity against H₂O₂-induced reactive oxygen species (ROS) formation was only observed in G1 extract. In addition, G1 extract showed more potent inhibitory effect on H₂O₂-induced apoptotic cell death than CP extract, as examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and fluorescence microscopy. Expression levels of various apoptosis-related genes, including B-cell lymphoma 2-associated X protein, p53, capase-3, and inflammatory cytokines, in H₂O₂-treated cells were significantly decreased by the treatment of G1. Taken together, the present study suggests that a new strain of red seaweed G1 can recover oxidative stress effectively by improving the imbalance of ROS generation and has a potential to be used a functional ingredient as an antioxidant source.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1143-1150
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• 2005

Antioxidative activities of 5 common edible seaweeds in Korea, three brown algae (seaweed fusiforme, sea mustard, sea tangle), one green algae (sea lettuce) and one red algae (laver), were examined. The antioxidative activities of ethanol extracts from these seaweeds were examined by measuring of inhibition rates against iron-induced linoleate peroxidation, DPPH (1,1-diphenyl -2-picrylhydrazyl) radical generation and MDA-BSA (malondialdehyde-bovine serum albumin) conjugation. Sea lettuce ethanol extract showed the strongest anti-oxidative activity among them, especially in inhibition against conjugation of lipid peroxide and protein. Second to sea lettuce, laver and sea tangle ethanol extracts showed high DPPH radical scavenging activity and inhibition against MDA-BSA conjugation. However, seaweed fusiforme and sea mustard ethanol extracts did not show antioxidative activities. Sea mustard contained the highest total flavonoids (11.33 mg/g dry wt) and sea lettuce contained the highest total polyphenol (8.97 mg/g dry wt) among these seaweeds. In addition, there was strong positive correlation between the antioxidative activity and total polyphenol content in these seaweeds, suggesting polyphenol compounds may contribute to antioxidative effect of seaweeds. From these data, it is suggested to consume much of seaweeds such as sea lettuce, laver and sea tangle to prevent age-related chronic diseases, and also develope neutraceutical products using polyphenol rich fraction from sea lettuce.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.427-431
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• 1999

This study was conducted to investigate the inhibitory activity of water extracts and its enzymatic hydrolysates from algae against angiotensin-I converting enzyme (ACE). The 7 kinds of algae were extracted with water at $50^{\circ}C,\;70^{\circ}C$ and $98^{\circ}C$. ACE inhibitory activities of water extracts were the highest at $70^{\circ}C$, and those of ceylon moss, layer, green layer, sea mustard, seaweed fusiforme sea tangle and sea staghorn were $10.9\%,\;9.3\%,\;8.9\%,\;8.2\%,\;7.5\%,\;7.1\%$ and $7.0\%$, respectively. Layer, green laver sea mustard and ceylon moss of high ACE inhibitory activities among the 7 kinds of water extracts were hydrolyzed by maxazyme and papain during 24hrs. ACE inhibitory activity of enzymatic hydrolysates was higher than that of water extracts, and was the highest in enzymatic hydrolysates of laver among the tested samples. In laver hydrolysates by proteases, the highest ACE inhibitory activity and peptide-nitrogen contents were observed at 8 hours hydrolysis and the hydrolysates by maxazyme showed relatively higher activity than those by papain(31.3 and $27.9\%$, respectively). But peptide-nitrogen contents were greater in papain hydrolysates than in maxazyme.

• Journal of Nutrition and Health
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• v.38 no.7
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• pp.586-604
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• 2005

A reliable nutrient database is a prerequisite for accurate calculation of dietary intakes. The folate database currently available in Korea, however, is not reliable because the values were obtained from published data in other countries using ineffective methods to extract folates from the food matrix. The purpose of this study was to complement the folate database by analyzing folate content in foods using a more effective method to extract food folates (trienzyme treatment). Folate content per unit weight was highest in laver, fermented soybeans, soybean, spinach, black soybeans, crown daisy, mung beans, and quail's egg in descending order. Legumes, leafy greens, eggs, and seaweeds were rich in folate, and meats, chicken, fish, and some fruits contained less folate. Some of the analyzed values were 10 times higher than those in the currently available database. Folate values of 423 foodcodes out of 2,932 foodcodes ($14.4\%$) in the database in the 7th revision in the Recommended Dietary Allowances for Koreans can be replaced by those analyzed in this study. Since folate values of rice and Kimchi, which are core dishes of Koreans, in the newly established database are higher than those in the current database, folate intake assessed using our data will be higher than that using the current available database. Folate content in more foods commonly consumed in Korea are needed to update the folate database. Meanwhile, folate values presented here can be used to assess dietary folate intake of the Korean population.