• Natural Product Sciences
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• v.8 no.3
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• pp.103-107
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• 2002

Four known sesquiterpenes, laurinterol (1), isolaurinterol (2), aplysinal (3) and aplysin (4) were isolated from the Korean red alga Laurencia okamurae off Cheju Island, Korea. Their structures were identified by comparison with the literature data. Compounds 1-4 showed potent cytotoxicity against A549, SK-OV-3, SKMEL-2, XF498, and HTl5 cell lines with $EC_{50}$ values ranging from 1.2 to 17.6 ${\mu}g/ml$.

• Natural Product Sciences
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• v.19 no.1
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• pp.61-65
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• 2013

A bioassay-guided fractionation of the extract of the fungus Paecilomyces variotii, which was derived from the giant jellyfish Nemopilema nomurai, led to the isolation of antibacterial compounds viriditoxin and its monomeric subunit semi-viriditoxin. Viriditoxin showed significant antibacterial activity against several marine fish and human pathogens including MDR strains. Significant potencies against resistant pathogens such as VRE Enterococcus faecium, VRE Enterococcus faecalis, and MRSA were highly interesting. Viriditoxin also showed notable antibacterial activity against the fish pathogen Streptococcus iniae. Its potency was over 100-fold higher than oxytetracycline which is employed as a general antibiotic for aquaculture.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.390-395
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• 2017

The antibacterial activity of ethanol (99.9%) extracts from marine micro-algae, namely, Mixed A (Pavlova sp., Thalassiosira weissflogii, Tetraselmis suecica and Isochrysis galbana were mixed with 1:1:1:1 ratio), Chlorella vulgaris, Nannochloropsis oculata and Chaetoceros calcitrans were estimated against food-borne bacteria, namely, Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus and Bacillus cereus. The extracts from these marine micro-algae showed potent antibacterial activity against all tested bacteria by the paper disk method. The extracts from C. vulgaris showed the strongest antibacterial activity against E. coli with minimum inhibitory concentration (MIC) of 0.62 mg/mL, and minimum bactericidal concentration (MBC) of 2.50 mg/mL. The extract from C. vulgaris contained 2 active compounds, 38.8% linoelaidic acid and 30.0% phytol. These results indicated that the ethanol extract from C. vulgaris may be a putative natural antibacterial agent against food-borne bacteria.

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.1
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• pp.20-28
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• 2020

Symbiodinium is a dinoflagellate genus that coexists with coral reefs and is known to provide ultraviolet (UV) protection in nature through the synthesis of mycosporin-like amino acids (MAA). In order to develop a natural and ecofriendly sunblock for use in summer resorts, the possibility of using a Symbiodinium microbiome extract or an MAA was investigated. Two sunblocks, one containing 7% Symbiodinium extract and the other containing MAA were prepared to be tested on hairless mice and human skin. In this clinical study, the sun protection factor (SPF) and Protection factor of UV A (PFA) values of the sunblock containing either Symbiodinium extract or MAA were determined. The SPF values of the sunblock containing Symbiodinium extract and MAA were 10.43 and 10.83, respectively, and the PFA values were 3.42 and 3.39, respectively. Based on their PFA values of ≥2, the UV A protection can be graded as PA+ (low) for both the sunblocks. In addition, the UV-blocking extract of Symbiodinium has a low phototoxicity and cytotoxicity, reducing the possibility of a heavy feeling to the skin or a foreign-body sensation caused by residue build-up. The low toxicity feature of the major sunblock component will also prevent side effects, such as allergic reactions. Although Symbiodinium extract or MAA alone do not provide effectiveprotection against UV irradiation, their protection capacity can be complemented by the addition of inorganic UV-protecting compounds.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.672-681
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• 2009

The aim of this study was to evaluate the antioxidant activities of enzymatic digests from citrus by-products (CBPs) prepared by high speed drying (HSD). HSD needs a short time (60 min) for drying and can be used in a commercial scale. Enzymatic digests were prepared from the CBPs using 6 enzymes such as aminoglucosidase (AMG), celluclast, pectinex, termamyl, ultraflo, and viscozyme. Antioxidant activities of AMG digest from CBPs were evaluated by different in vitro models such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, alkyl, $H_2O_2$ scavenging, metal chelating, lipid peroxidation, and comet assays, and exhibited strong activities. The antioxidant compounds were detected by an high performance liquid chromatography (HPLC) coupled on-line to an 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid ($ABTS^+$) scavenging detection system, and found that hesperidin was the key compound. Therefore, the results obtained in this study suggest that HSD is an effective method to transform wet CBPs into dried form, and CBPs are potential source of natural antioxidant.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1058-1067
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• 2000

In this study, eel, puffer and snake head fish, which are widely taken and highly valued for processing into baked fish, soup or fish juice were studied by classifying them into wild fish and cultured fish, and evaluated in terms of taste. The samples were gathered in the area including Kimhae, Samchonpo and Haman in Kyungsangnam-do, Kangsu-Gu in Pusan and Bukcheju-Gun in Cheju-do. Proximate compositions, the content of nucleotides and their related compounds, total and free amino acids, organic acids and fatty acids of the fishes were analysed. Generally, as for the compositions, wild fish had a higher crude fat content and a lower moisture content as compared with cultured fish, while there was no great difference between them in terms of crude protein and ash contents. Nucleotides and their related compounds including ATP, ADP, AMP, IMP, HxR, Hx were detected, and the amounts of which were nearly the same with respect to the growth conditions. IMP content was high in all of the samples, while ATP content was extremely low. Total 17 amino acids were detected from the samples, and most of the samples had high contents of glutamic acid, aspartic acid, lysine, leucine, glycine, alanine and arginine, and low contents of cystein, isoleucine and methionine. As for the other amino acids, generally same level of contents were detected for each samples. In cases of eel and snake head fish, the wild fish had higher total amino acid contents in comparison with cultured fish. And the result to the contrary was obtained for the case of puffer. Sample fishes had nearly the same compose distribution of free amino acid though the contents of which were a little different according to the samples. Each sample had high contents of taurine, hydroxyproline, glutamic acid, glycine, cystathionine, ${\beta}-aminoisobutyric$ acid and lysine. Total organic acid contents of cultured fish was higher than that of wild fish. All fishes commonly had high contents of lactic acid, iso-valeric acid, oxalic acid and fumaric acid. High levels of $C_{16:0},\;C_{16:1},\;C_{18:1(cis)},\;C_{18:3},\;and\;C_{22:6}$ were shown in all of the samples and ${\omega}-3$ polyunsaturated fatty acid content of cultured fish was higher than that of wild fish, and as for the essential fatty acid, wild fish has higher content in comparison with cultured fish.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.721-729
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• 2013

To improve the quality and functionality of the low salt squid Jeot-gal, extracts from three types of medicinal and edible plants (bay leaf, green tea, pine needle) were added. The quality characteristics, bioactivities, and shelf-lives of these preparations were determined at three different fermentation temperatures. The pH decreased more rapidly at higher temperatures, while the amount of volatile basic nitrogen (VBN), total viable cells, and amino nitrogen ($NH_2$-N) increased. The shelf-lives of Jeot-gal with natural plant extracts at $10^{\circ}C$ were 34~35 days, similar to the control. The major free and compositional amino acids of Jeot-gal were glutamic acid, proline, and alanine, while the major nucleotides (and related compounds) were hypoxanthine and inosine. In bioactivity assays, samples supplemented with plant extracts showed higher bioactivities than the control. The DPPH radical scavenging activity of ethanol extracts from Jeot-gal were stronger than the water extracts; in contrast, the water extracts were stronger for hydrogen peroxide scavenging activity. However, superoxide dismutase (SOD)-like activity and ${\beta}$-glucuronidase inhibitory activity were moderately low at 20 mg/mL. Based on sensory evaluation results, the quality of low salt squid Jeot-gal with natural plant extracts is similar to the control. Therefore, low salt squid Jeot-gal with natural plant extracts can be commercialized as a functional fermented food.

• Asian Journal of Atmospheric Environment
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• v.5 no.3
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• pp.157-163
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• 2011

Atmospheric aerosol deposition caused by Asian dust (KOSA) events provide nutrients, trace metals, and organic compounds over the Pacific Ocean that enhance ocean productivity and carbon sequestration and, thus, influence the atmospheric carbon dioxide concentrations and climate. Using dust particles obtained from the snow layers on Mt. Tateyama and the surface sand of Loess Plateau in incubation experiments with natural seawater samples on a shipboard, we demonstrate that dust-particle additions enhanced the bacterial growth on the first day of incubation. Gram-positive bacterial group and alpha-proteobacteria were specifically detected form seawater samples including the mineral particles. Although the remarkable dynamics of trace elements and nutrients depend on dust-particle additions, it is possible that organic compounds present in the mineral particles or transported microbial cells could also contribute to an increase in the quantities of bacteria. The chlorophyll concentrations at fractions of every size indicated a similar pattern of change between the seawater samples with and without the dust-particle additions. In contrast, the chlorophyll measurement using submersible fluorometer revealed that the dynamics of phytoplankton composition were influenced by the dust-particles treatments. We conclude that the phytoplankton that uses the bacterial products would increase their biomass. We show that KOSA deposition can potentially alter the structures of bacterial communities and indirectly influence the patterns of marine primary production in the Pacific Ocean.

• Asian Journal of Atmospheric Environment
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• v.11 no.1
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• pp.15-28
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• 2017

The adsorptive removal properties of synthetic A4 zeolite were investigated against a total of 16 offensive odors consisting of reduced sulfur compounds (RSCs), nitrogenous compounds (NCs), volatile fatty acids (VFAs), and phenols/indoles (PnI). Removal of these odors was measured using a laboratory-scale impinger-based adsorption setup containing 25 g of the zeolite bed (flow rate of $100mL\;min^{-1}$). The high est and lowest breakthrough (%) values were shown for PnIs and RSCs, respectively, and the maximum and minimum adsorption capacity (${\mu}g\;g^{-1}$) of the zeolite was observed for the RSCs (range of 0.77-3.4) and PnIs (0.06-0.104), respectively. As a result of sorptive removal by zeolite, a reduction in odor strength, measured as odor intensity (OI), was recorded from the minimum of approximately 0.7 OI units (indole [from 2.4 to 1.6]), skatole [2.2 to 1.4], and p-cresol [5.1 to 4.4]) to the maximum of approximately 4 OI units (methanethiol [11.4 to 7.5], n-valeric acid [10.4 to 6.5], i-butyric acid [7.9 to 4.4], and propionic acid [7.2 to 3.7]). Likewise, when removal was examined in terms of odor activity value (OAV), the extent of reduction was significant (i.e., 1000-fold) in the increasing order of amy acetate, i-butyric acid, phenol, propionic acid, and ammonia.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.426-433
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• 2009

Fish scales have potential in functional food preparation due to their antioxidant and antihypertensive properties. We investigated the angiotensin I converting enzyme (ACE) inhibitory activity of Tilapia mossambica scale extracts. Hydrolysates of tilapia scales were prepared by enzymatic extraction using five proteases (${\alpha}$-chymotrypsin, Alcalase, Kojizyme, Protamex and trypsin) after scales were treated with hot water for 3 hr. Scale enzymatic hydrolysates prepared using both hot water and enzyme treatments exhibited elevated hydrolysis (about 25%-55%) compared to only enzyme treatment (about 15%-45%). Enzymatic hydrolysates (1 mg/mL) prepared by both hot water and enzyme treatments also showed significantly increased ACE inhibitory activities from about 20%-75%. The pattern of ACE inhibitory activities was similar to the degree of hydrolysis. Alcalase and ${\alpha}$-chymotrypsin hydrolysates displayed the highest ACE inhibitory activities ($IC_{50}$ = 0.83 mg/mL and 0.68 mg/mL, respectively). In addition, the ACE inhibitory effects of $IC_{50}$-chymotrypsin hydrolysates increased with decreasing molecular weight (5 kDa>, 10 kDa> and 30 kDa>), with the 5 kDa> fraction displaying the highest ACE inhibitory activity (about 89.9% and $IC_{50}$ = 0.1 mg/mL). We suggest that the peptide compounds of enzymatic hydrolysates prepared from tilapia scale enhances ACE inhibitory activity and might be useful as an antihypertensive material.