• Korean Journal of Microbiology
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• v.49 no.4
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• pp.403-414
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• 2013

This study evaluated the physicochemical and microbiological characteristics and antioxidant properties of yogurt samples fermented with lactic acid bacteria (LAB) obtained from pickled cabbage. API 50 CHL systems and 16S rRNA nucleotide sequence analyses revealed that the isolates were Lactobacillus casei PC05 and L. acidophilus PC16. Cell counts, titratable acidity, and viscosity of the yogurt samples fermented with L. acidophilus PC16 were significantly higher than those of the samples fermented with L. casei PC05 (P<0.05). The detected cell counts and physicochemical properties were significantly lower in plain yogurt than in soy yogurt (P<0.05). Yogurt samples fermented with L. acidophilus PC16 exhibited higher antioxidant activity, measured as ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and chelate ferrous ions, than those fermented with L. casei PC05. However, the ability to scavenge superoxide anions and superoxide dismutase (SOD) activity were significantly (P<0.05) higher in yogurt samples fermented with L. casei PC05 compared to those in samples fermented with L. acidophilus PC16. The antioxidant activity of soy yogurt was significantly (P<0.05) higher than that of plain yogurt. The antioxidant activity of the tested strains resulted in lipid peroxidation inhibition (in vitro), which may be related to the elimination of free radicals, chelating ability, and reducing power. There were no significant differences in the physicochemical properties and antioxidant activities of the yogurt samples during cold storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.323-327
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• 2014

This study was carried out to provide basic data on the anion, element, chromatic and antioxidant activities of commercial dried lavers cultivated from Seocheon, Wando, Goheung and Busan in Korea. The highest concentrations of several anions ($Cl^-$, $NO_3{^-}$, $SO_4{^2-}$, and $PO_4{^3-}$ per 100 g of dried laver) were 412.00 mg in Wando, 545.90 mg in Goheung, 297.35 mg in Seocheon, and 79.70 mg in Wando, respectively. The highest concentrations of N, C, and S were 6.40%, 41.36%, and 0.98%, respectively, in dried laver cultivated from Wando. Hunter's color values were significantly high in the order of Seocheon < Goheung < Busan < Wando for lightness, Wando < Busan < Goheung < Seocheon for redness, and Goheung < Seocheon < Busan < Wando for yellowness in the dried lavers. Total phenolic content and DPPH (1,1-diphenyl-2-picryl-hydrazyl) radical scavenging activities showed highest values of 166.10 mg/100 g and 28.48%, respectively, in dried laver cultivated from Wando.

• Journal of Life Science
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• v.29 no.2
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• pp.164-172
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• 2019

In Korea, shiitake mushroom, Lentinula edodes, is cultivated on artificial medium containing oak sawdust and wheat bran. The annual production of spent mushroom substrate (SMS) of shiitake, a byproduct of the mushroom industry, is estimated to reach over 50,000 tons per year. This study aimed to improve the use of SMS as a novel bioresource. Hot water extracts of SMS after the first and third harvest were prepared and their bioactivities evaluated. Hot water extracts of uninoculated medium and shiitake were used as controls. Extracts of SMS showed higher radical scavenging of DPPH anions, ABTS cations, nitrites, and a higher reducing power than those of shiitake or medium extracts. After the first and third harvests at 0.5 mg/disc, SMS extracts showed no antibacterial or antifungal activities against the pathogenic and food-spoilage bacteria and fungi. However, they showed good inhibitory activities against ${\alpha}$-glucosidase at 0.5 mg/ml. In addition, SMS extracts had strong anti-coagulation activities via their inhibition of thrombin, prothrombin, and blood coagulation factors without platelet aggregation activity. Our results suggested SMS should no longer be perceived as a useless byproduct but should be understood as a novel bioresource, the extracts of which could be developed as antioxidant, antidiabetic, and antithrombosis agents.