• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.143-148
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• 2022

This study was to investigate an analytical method for determining dieckol content in Ecklonia stolonifera extract. According to the guidelines of International Conference on Harmonization. Method validation was performed by measuring the specificity, linearity, precision, accuracy, limit of detection (LOD), and limit of quantification (LOQ) of dieckol using high-performance liquid chromatography-photodiode array. The results showed that the correlation coefficient of calibration curve (R²) for dieckol was 0.9997. The LOD and LOQ for dieckol were 0.18 and 0.56 ㎍/mL, respectively. The intra- and inter-day precision values of dieckol were approximately 1.58-4.39% and 1.37-4.64%, respectively. Moreover, intra- and inter-day accuracies of dieckol were approximately 96.91-102.33% and 98.41-105.71%, respectively. Thus, we successfully validated the analytical method for estimating dieckol content in E. stolonifera extract.

• Journal of Life Science
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• v.20 no.12
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• pp.1851-1858
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• 2010

Estrogen deficiency in peri- and postmenopausal women results in variety of neurovegetative, psychic and somatic symptoms, and may contribute to severe diseases within the aged female population. Ecklonia stolonifera (ES) is an edible brown algae traditionally used in fishery towns in Far East Asia. This study was performed to investigate the effects of ES extracts on blood flow and serum lipid concentration in ovariectomized rats. Weight-matched female Sprague-Dawley strain rats were assigned to four groups. Three groups were surgically ovariectomized (OVX). The fourth group was sham operated. Rats were randomly assigned to the following groups: sham-operated rats (Sham), ovariectomized control rats (OVX-CON), ovariectomized rats supplemented with ES extract at 50 mg/kg bw/day (OVX-ES50) and ovariectomized rats supplemented with ES extract at 200 mg/kg bw/day (OVX-ES200). Serum total cholesterol and triglyceride contents decreased in the sham group compared to the OVX-CON group. Six weeks feeding of ES extract resulted in a significant (p<0.05) lowering of serum triglyceride and a lowering tendency of total cholesterol level. The level of Hdl-cholesterol in serum increased by supplementation of ES extracts at 50 mg/kg and 200 mg/kg bw/day (p<0.05). Blood passage time of the ES extracts-supplemented group was higher than the OVX-CON group. The ability of platelet aggregation of groups treated with ES extracts was less than that of the OVX-CON group. These results suggest that the beneficial effects of ES extract may be used to possibly improve on the metabolic syndrome of menopausal women.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1769-1775
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• 2010

Menopause is often associated with the incidence of several chronic diseases including osteoporosis, cardiovascular disease, and obesity. The purpose of this study was designed to evaluate the possibility of osteoporosis prevention in postmenopausal women. In this study, we investigated the effects of Ecklonia stolonifera (ES) extracts on bone turnover markers in ovariectomized rats. For this study, the following four groups of 9-week-old Sprague-Dawley rats were evaluated over 6 weeks: normal rats (SHAM), ovariectomized rats (OVX-CON) and ovariectomized rats that were treated with ES extracts. We measured the osteocalcin and C-telopeptide of collagen cross-links (CTx) content, enzyme ALP activity in serum and collagen content in the cartilage, bone, skin and lungs. We found that the levels of indicators of bone metabolism such as alkaline phosphatase (ALP), osteocalcin and CTx were lower in rats in the ES extract group than the OVX-CON group. In addition, the collagen contents in the bone, cartilage, skin and lungs decreased in response to ovariectomy, but the levels of collagen were greater in the bone of rats that were treated with ES extract than in the bone of rats in the OVX-CON group. These results suggest that the ES may be an effective functional food to prevent osteoporosis in postmenopausal women.

• Journal of Nutrition and Health
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• v.41 no.1
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• pp.5-12
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• 2008

In order to investigate whether Eisenia bicyclis (EB) as a functional food material improves serum lipid status, supplementation of EB powder or EB extract to the high fat/cholesterol diet was tested in 6-week old male Sprague-Dawley rats for four weeks. In the first experiment, four kinds of seaweed powder -Eisenia bicyclis (EB), Undaria pinnatifida (Up), Laminaria japonica (LJ), and Ecklonia stolonifera (ES) were compared with alginic acid (ALG) as well as control. In the second experiment, EB water extract and EB ethanol extract and EB pill containing EB and LJ powder were compared with the EB powder. Amounts of dietary fiber contained in experimental diets were adjusted to provide 5% of diets. Serum total cholesterol was significantly lower only in rats fed LJ or EB powder, but HDL cholesterol was higher in rats fed UP, LJ, ES or EB powder. Ratios of HDL-/total cholesterol of all seaweed groups including ALG were significantly higher than that of the control group. Serum triglyceride was lower in LJ, EB nd ES powder groups than the control group. In comparison of EB extracts, triglyceride level was decreased in rats fed only EB water extract as compared to control rats, but HDL cholesterol was elevated with both water and ethanol extracts. Serum levels of total cholesterol, triglyceride were decreased and HDL cholesterol was increased by the EB pill. Serum levels of thiobarbituric acid-reactive substances were lower in rats fed ES powder, and EB powder, EB water extract or EB pill, as compared to the control rats. Supplementation of EB powder and EB pill reduced serum level of GOT and GPT, respectively, as compared to the control group. In conclusion, EB and EB pill improve serum lipid status and may be utilized as ingredient of functional foods for the purpose of improving serum lipid profile and inhibiting peroxidation of lipids.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.506-512
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• 2009

The antimicrobial activity of water and ethanol extracts from 30 species of algae was measured using the agar diffusion method and minimum inhibitory concentration (MIC) test. In agar diffusion method, the 95% ethanol extracts from 12 of the algae showed growth inhibition against the tested microorganisms. In particular, Ishige okamurai, Ecklonia stolonifera, Sargassum siliquastrum, Sargassum thunbergii, Colpomenia bullosa, and Ecklonia cava had strong antibacterial activities against Gram-positive bacteria at 4 mg/mL. In the results of the MIC test, S. siliquastrum showed the most antimicrobial activity, where its MIC values ranged from 0.005 to 0.0075% against Listeria monocytogenes, Clostridium perfringens, and Basillus subtilis. In the thermal stability test, for the ethanol extracts of I. okamurai, E. cava, S. siliquastrum, S. thunbergii, and C. bullosa, the extracts proved to maintain high antimicrobial activities when they were treated at $121^{\circ}C$ for 15 min. In the pH stability test, the antimicrobial activity of the S. siliquastrum ethanol extract was stable from pH 2 to 10, whereas the activity of the other species ethanol extracts were weakened under pH 10 against several microbes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1293-1296
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• 2005

Nitrite plays an important role in the formation of carcinogenic nitrosamine. In order to effectively inhibit the formation of carcinogenic nitrosamine in food and biological systems, scavenging of residual nitrite is necessary. In screening test of nitrite-scavenging effect of seaweed, The methanol extract from Phaeophyta was more effective than those from Rhodophyta and Chlorophyta. Among the brown algae family, Laminariaceae, A. cribrosum (90.4$\%$) and E. cava (80.1$\%$), E. stolonifera (79.0$\%$) that belong to genus Ecklonia showed marked nitrite-scavenging effect at pH 1.2. Furthermore, these algae showed potent reducing power and radical scavenging activity. The nitrite-scavenging effect was correlated with level of reducing power.

• Korean Journal of Pharmacognosy
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• v.24 no.4
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• pp.299-303
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• 1993

The antioxidant activity of methanol extracts of plants and marine algae was tested by using 1,1-diphenyl-2-picrylhydrazyl(DPPH). Five plant extracts(Prunus davidiana, Eriobotrya japonica, Artemisia iwayomogi, Stirodella tolyrrhiza and Ulmus davidiana) and two algae (Ecklonia stolonifera and Symphycoladia latiuscula) were found to be the most effective in DPPH radical scavenging activity. The methanol extract obtained from the stems of Prunus davidiana was fractionated with several solvents. The ethylacetate soluble fraction exhibiting the strongest antioxidant activity was further purified by repeated silica gel and Sephadex LH-20 column chromatography. Antioxidant flavonoids and flavonoid glycosides were isolated and the most active ones was identified as (+)-catechin by MS, $^1H-NMR$ and $^{13}C-NMR$. Its antioxidant activity was higher than that oil vitamin C.

• Food Science and Preservation
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• v.22 no.2
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• pp.290-296
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• 2015

The antioxidant and ${\alpha}$-glucosidase inhibition activities of 10 kinds of seaweeds Ecklonia cava (EC), Ecklonia stolonifera (ES), Eisenia bicyclis (EB), Capsosiphon fulvescens (CF), Sargassum fulvellum (SF), Undaria pinnatifida (UP), Sargassum thunbergii (ST), Codium fragile (CFr), Hizikia fusiformis (HF), and Enteromorpha prolifera (EP) were investigated. Among all the tested seaweed extracts, the total polyphenol and flavonoid contents of the EB extract were highest 150.81 mg/g and 77.02 mg/g, respectively. The DPPH and ABTS radical scavenging abilities of the EB ethanol extract (1 mg/mL) were 86.26% and 99.71%, respectively, and its SOD-like activity and reducing power were 21.34% and 1.710 ($OD_{700}$). The ${\alpha}$-glucosidase inhibition activities of the EC, EB, and ST were above 98% at the 0.1 mg/mL concentration. These results suggest that seaweed extracts effectively prevent the what of antioxidants and decrease the blood glucose level, and may be used to develop various functional products.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.1008-1013
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• 2004

Effects of extraction conditions and molecular fractionation on anticoagulant activities of major brown seaweeds in Korea were investigated. Hot water extracts of C. costata, U. pinnatifida (Sporophyte), L. japonica, K. crassifolia, E. stolonifera, E. bicyclis, S. horneri, and E. kurome increaced activated partial thromboplastin time (APTT) over 190 seconds, which may be related to intrinsic pathway of blood coagulation. Hot water extract of E. Kurome (EKJ) was further fractionated by ethanol precipitation. EKJ-eim, ethanol-insoluble material of EKJ, showed higher anticoagulant activity than EKJ. EKJ-eim was further fractioned with ultrafiltration. EKJ-eim 1, (over 100 kDa) fraction showed higher APTT activity than EKJ-eim. A EKJ-eim 1 was sulfated polysaccharide consisting of fucose, xylose, mannose, galactose, glucose and, sulfate at molar ratio of 1 : 0.05 : 0.10 : 0.15 : 0.17 : 1.46. The anticoagulant activity increased as sulfate content and molecular weight increased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.191-195
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• 2002

In previous reports the authors have screened the inhibition effects of marine algae extracts on halitosis, and demonstrated that a brown algae, Eisenia bicyclis (' Daehwang') possess not only strong deodorant effect bug also considerable anticariogenic activities. In this study, we screened antibacterial effects of various marine algae, and measured minimum inhibitory concentration (MIC) value of them against mutans streptococci in vitro. Among the 27 species of marine algae, $80\%$ ethanol extract of dried sea-mustard, Laminaria japonica ('Dasima') showed the strongest inhibition activity against Streptococcus mutans KCTC 3300. The extracts of Ulva lactuca ('Galparae'), Codium fragile ('Cheonggak'), Ecklonia cava ('Gamtae'), E. stolonifera ('Gompi') and Undalia Pinnatifida ('Miyeok') showed slightly weaker inhibitory potency than L. japonica. Differences of MIC values in $80\%$ ethanol extract of some species of marine algae were observed depending on test bacterial species, i.e., S. mutans KCTC 3300 or S. sobrinus KCTC 3307. Eighty percent ethanol extract of dried L japonica was fractionated with diethyl ether, chloroform, ethyl acetate, n-buthanol and water successively, The ether-soluble fraction had inhibitory effect on S. mutans KCTC 3300, however the inhibitory effects were not found in the other fractions. The MIC values of $80\%$ ethanol extract and ether fraction were 180 and 105 $\mu$g/mL respectively, while no significant inhibition activity of water-soluble fraction was found even when the fraction was added up to 5,500 $\mu$g/mL.