• Food Science and Preservation
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• v.11 no.2
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• pp.207-213
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• 2004

Methanol extracts were prepared from 32 medicinal herbs of the extracts were tested their microbial inhibition activities against food borne pathogens and/or food poisoning microorganisms, food-related bacteria and yeast. Methanol extracts of Cinnamomum cassia, Paeonia suffruticosa, Alnus japonica, Eugenio caryophyllata and Illicium verum exhibited antimicrobial activity for the microorganisms tested, except lactic acid bacteria and yeast. Minimum inhibitory concentrations(MIC) were about 5 mg/mL for Bacillus subtilis, Staphylococcus epidermidis and Pseudomonas aeruginosa. Cell growth of lactic acid bacteria was inhibitied, but greatly on Leuconostoc mesenteroides. The phenolic compound contents were 10.98 mg/g, 10.31 mg/g, 8.55 mg/g and 6.69 mg/g in Thea sinensis, Eugenia caryophyllata, Alnus japonica and Artenisia capillaris, respectively. Antimicrobial activity appeared to be related to phenol compound content in medicinal herbs. The methanol extracts of medicinal herbs could be suitable for the development of a food preservative.

• Journal of Food Hygiene and Safety
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• v.30 no.3
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• pp.281-288
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• 2015

Vibrio is a genus of Gram-negative, curved, halophilic, and non-spore-forming bacteria. Some of the Vibrio species, such as V. cholerae and V. parahaemolyticus, often contaminate seafood products and occasionally cause human diseases when the seafood products are ingested. A total of 24 Vibrio strains were isolated from shrimp samples on Thiosulphate citrate bile salt sucrose (TCBS) media in this study. All of the 24 isolates were confirmed to belong to the genus Vibrio by using 16S rRNA gene sequence analyses. Vitek 2 system and species-specific polymerase chain reaction (PCR) methods were used to further identify a total of 29 Vibrio strains at the species level, including the 24 shrimp Vibrio isolates and five Vibrio reference strains. The specificities of the two methods to identify Vibrio strains at the species level were compared in this study. The species-specific PCR method was designed to detect five different Vibrio species, such as Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio alginolyticus, and Vibrio mimicus. From the 24 Vibrio shrimp isolates, the Vitek 2 system method could identify 15 (62.5%) strains as Vibrio species and 7 (29.2%) strains as non-Vibrio species, but could not identify the rest 2 (8.3%) strains. But species-specific PCR method could identify 16 (66.7%) strains as Vibrio species and could not identify the rest 8 (33.3%) strains. Among the 24 Vibrio shrimp strains, these two methods could unanimously identify 7 (7/24, 29.2%) strains (2 V. parahaemolyticus, 4 V. alginolyticus, and 1 V. mimicus). Considering that such different identification results were obtained using the two different methods in this study, identification method for Vibrio species must be carefully chosen.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.4
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• pp.355-364
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• 2016

This study was initiated to evaluate the antioxidant and antimicrobial activities of methanol extract (ME) and hot water extract (HWE) obtained from the fruiting bodies of medicinal mushroom, Phellinus gilvus. The free radical scavenging activity of ME from P. gilvus on 1,1-diphenyl-2-picrylhydrazyl (DPPH) were 93.65% at 2 mg/mL, which was comparable with the positive control, butylated hydroxytoluene (BHT, 96.97%) at the same concentration. The ferrous ion-chelating ability of ME and HWE was significantly higher than that of BHT at all concentration levels. The antimicrobial assay of ME was performed against six bacteria and one species of fungus. ME exhibited antibacterial activity against 5 out of 6 bacteria: Staphylococcus aureus, Streptococcus mutans, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa; whereas, ME did not show antimicrobial activity against gram-negative bacterium Vibrio vulnificus and fungal species Candida albicans. The minimum inhibitory concentration (MIC) of ME against 5 strains of bacteria, such as S. aureus, S. mutans, B. subtilis, E. coli, and P. aeruginosa, was 100, 100, 50, 100, 200 mg/mL, respectively. The results suggest that good antioxidant and microbial activities of P. gilvus fruiting bodies might be used for natural antioxidant and antimicrobial agents.

• Journal of Life Science
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• v.13 no.3
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• pp.333-342
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• 2003

The pathogenic effort of high glucose, possibly in concert with fatty acids, is mediated to vascular complications of diabetes via increased production of reactive oxygen species(ROS), reactive nitrogen species(RNS), and subsequent oxidative stress. This study was carried out to investigate the suppressive effect of buchu(Allium tuberosum) on oxidative stress in streptozotocin(STZ)-induced diabetes in Sprague Dawley male rats. The effect of buchu supplementation (10%) on lipid peroxidation, and antioxidative defense system in blood and liver was compared among normal rats fed basal diet(normal) and diabetic rats fed basal diet(DM-control) or 10% buchu-supplemented diet(DM-buchu). Diabetes was experimentally induced by the femoral muscle injection of 50 mg STZ per kg of body weight. Animals were sacrificed after 4 wks of experimental diets feeding. The induction of diabetes by STZ elevated the level of lipid peroxidation represented by thiobarbituric acid-reactive substances(TBARS) and conjugated dienes in plasma, LDL, liver, and erythrocytes. 10% buchu-supplemented diet significantly reduced the levels of conjugated dienes in erythrocytes(p<0.05) and lowered TBARS in liver and LDL to the levels of control. Induction of diabetes by STZ elevated Mn-superoxide dismutase(Mn-SOD) activity and lowered activities of glutathionine reductase(GSH-red) and glutathionine peroxidase(GSH-px). Catalase activity was not affected by the induction of diabetes by STZ. However, buchu supplementation to diabetic rats significantly elevated catalase activity(p<0.05) and slightly elevated GSH-px and GSH-red activities in liver. GSH levels of blood and liver were lowered or not changed by induction of diabetes by STZ, respectively, while buchu supplementation to diabetic rats significantly elevated hepatic GSH level (p<0.05). In conclusion, it can be concluded that buchu might be a food source to attenuate oxidative stress in diabetic patients by inhibiting lipid peroxidation, by increasing hepatic GSH level, and by inducing anti-oxidative enzyme systems.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.367-375
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• 2010

The bacteriological and physiochemical analysis of sea water and sediments in Tongyeong harbor was conducted to evaluate sanitary conditions. The samples were collected at 8 stations established once a month from June, 2008 to May, 2009. During the study period, the range of temperature was from 6.7 to $25.2^{\circ}C$, transparency ranged from 1.2 to 2.6 m, chemical oxygen demand ranged from 1.90 to 2.92 mg/L, dissolved oxygen ranged from 6.2 to 10.5 mg/L, dissolved nitrogen ranged from 0.052 to 0.098 mg/L, phosphate ranged from 0.044 to 0.065 mg/L, respectively. Seafood, if eaten raw, carries the risk of food poisoning. Seafood poisoning is often cause by pathogenic microorganism originating from fecal contamination, such as Salmonella sp., Shigella sp. and norovirus. Fecal coliforms are an important indicator of fecal contamination. Therefore, data on fecal coliform are very important for evaluating the safety of fisheries in coastal areas. So, we investigated the sanitary indicate bacteria. The coliform group and fecal coliform MPN's of sea water in Tongyeong harbor were ranged from < 1.8~22,000/100 mL (GM 164.9 MPN/100 mL) and < 1.8~7,900 MPN/100 mL (GM 33.7 MPN/100 mL), respectively. Total coliform were detected 97.0% in 96 of samples and 68.9% of total coliforms were fecal coliforms. These results similar to another seawater detection ratio of total coloforms and fecal coliforms. The Vibrios was isolated and identified with VITEK system. Four hundred eighty strains that were obtained from sea water samples in Tongyeong harbor Detection ratio Vibrio alginolyticus, 34.2%, Vibrio parahaemolyticus, 13.8%, Vibrio vulnificus 10.0%, and V. mimicus 12.5% respectively. Vibrio cholerae O1, was not detected. During the study period, the ranges of water content, ignition loss, COD, and acid volatile sulfates in sediments in Tongyeoung harbor were 41.0~57.4%, 7.8~10.5%, 6.51~9.30 mg/g, 0.04~0.09 mg/g, respectively. Heavy metals in sediment of Tongyeoung harbor were Cd, $0.10{\pm}0.05$; Cu, $4.79{\pm}8.20$; As, $1.95{\pm}0.17$; Hg, $0.10{\pm}0.07$; $Cr^{6+}$, $0.34{\pm}0.12$; Zn, $125.33{\pm}16.40$; Ni, $16.43{\pm}1.93$ mg/kg.

• Journal of the Korean Society of Food Culture
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• v.20 no.6
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• pp.709-714
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• 2005

Antibacterial activities of the freeze-dried bamboo sap dissolved into the water or 50% ethanol were determined and antimicrobial activity of bamboo sap dissolved into distilled water was most strong with 15 mm of the diameter of inhibiting clear zone against Listeria monocytogenes ATCC 19114 among gram positive bacteria tested, but it did not inhibit Bacillus subtilis ATCC 6633 at all, and the sap was most greatly inhibited the growth of Shigella dysenteriae ATCC 9361 among gram negative bacteria with 15 mm of the diameter of inhibiting clear zone. Bamboo sap dissolved into 50% ethanol most strongly inhibited the growth of L. monocytogenes ATCC 19114 and it also inhibited the growth of B. subtilis ATCC 6633 which did not show any with the sap dissolved into distilled water. The sap dissolved into 50% ethanol was most greatly inhibited the growth of S. dysenteriae ATCC 9361 among gram negative bacteria with 23 mm of the diameter of inhibiting clear zone, and it inhibited Vibrio parahaemolyticus WSDH 22, Vibrio vulnilicus ATCC 29307 and Escherichia coli O157 WSDH 54 with 16 mm of the diameter of inhibiting clear zone. However, Both of the saps dissolved in distilled water and 50% ethanol did not showed any inhibition against the lactic acid bacteria of Lactobacillus plantarum KCTC and Lactobacillus brevis KCTC. Most of the tested bacteria were more sensitive to the sap dissolved in 50% ethanol than the sap dissolved in distilled water. The lowest minimum inhibitory concentration of the bamboo sap dissolved into 50% ethanol was 0.6 mg eq./disc with L. monocytogenes ATCC 19114, but that of the sap dissolved into distilled water was 0.8 mg eq./disc with Staphylococcus epidermides ATCC 12228, S. dysenteriae ATCC 9361, L. monocytogenes ATCC 19114, Salmonella typhimurium WSU 2380 and V. parahaemolyticus WSDH 22. In a model food system of the sterilized chocolate milk, antibacterial activities of the sap dissolved into 50% ethanol were relatively stronger than those of the sap dissolved into distilled water and the activities against the bacteria tested were very similar each other. These result suggested the bamboo sap can be used as a natural food preservative.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.280-287
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• 2000

Three antimicrobial compounds (SL-l, SL-2 and SL-3) were isolated and identified from the marine red alga, Symphyocladia latiuscula. In addition, their biological functionalities such as cytotoxicity and desmutagenic activity were investigated. From the cryophyllized S. JatiuscuJa, SL-l, SL-2 and SL-3 were purified by solvent extractions and HPLC.SL-2 was crystallized in benzene-diethyl ether solvent. On the EI-MS spectra, it was found that they had three bromines in their structure which showed typical signal strength ratios at $M^+, [M+2]^+, [M+4]^+, [M+6]^+ (13: 38: 37: 12)$. $SL-l$ was identified as 2,3,6-tribromo-4,5-dihydroxybenzyl alcohol ($C_8H_7Br_3O_3, MW=374$) by NMR and MS spectra. SL-2 was assigned as 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether ($C_8H_7Br_3O_3, MW=388$) and confirmed by X-ray crystallographic analysis. SL-3 was presumed as an isomer of SL-2. Methanol extract of the S. latiuscula showed antimicrobial activities against all strains tested (bacteria, 15 strains; yeasts, 17 strains; fungi, 4 strains), much or less. The strongest inhibition activity of the methanol extract was to the Vibrio mimicus ($50 {\mu}g/ml$) and V. vulnificus ($50 {\mu}g/ml$). The mice injected intraperitoneally with 3 mg of SL-l and 5 mg of 5L-2 showed no acute toxicity response. SL-2 showed higher desmutagenic activity than SL-l against PhIP and MeIQx.

• Food Science and Preservation
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• v.22 no.4
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• pp.520-527
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• 2015

This study investigated the physiological activities of garlic extracts frozen at -20, -80, and $-196^{\circ}C$. To determine the optimum freezing temperature for maintaining garlic's physiological activity, antioxidant and antibacterial activities were investigated. The antioxidant activities were determined by DPPH radical scavenging ability, SOD-like activity, nitrite-scavenging ability, and reducing power. Total phenolic compounds and flavonoids of garlic extract frozen at $4^{\circ}C$ (control) were measured as $6.91{\pm}0.69{\mu}gGAE/g$ and $0.315{\pm}0.017{\mu}gQE/g$, respectively. Although the content of total phenolic compounds was not affected by the different freezing temperatures, the flavonoids contents of garlic extract frozen at $-20^{\circ}C$ were slightly decreased. The DPPH radical scavenging ability of garlic extracts (2 mg/mL) frozen at $-80^{\circ}C$ was 61%, whereas those frozen at $-20^{\circ}C$ and $-196^{\circ}C$ were 51%. SOD-like activity was slightly increased by freezing. However, the nitrite scavenging ability (18% at pH 3.0) and reducing power (OD700=1.6) were not affected by freezing temperatures. Antimicrobial activities did not show significant differences depending on freezing temperatures. Taken together, the physiological activities of the frozen garlic extracts were not significantly changed by the freezing temperatures; however, the antioxidant and antibacterial effects of the phenolic compounds and flavonoids were maintained at $-80^{\circ}C$. These results suggest that $-80^{\circ}C$ frozen garlic could maintain a higher quality than the conventional freezing method ($-20^{\circ}C$) without loss of physiological activities during the storage.