• Microbiology and Biotechnology Letters
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• v.49 no.4
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• pp.519-527
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• 2021

In this study, the hemolysis of Enterococcus faecalis BMSE-HMP strains, isolated from human breast milk, was investigated, and the anti-hemolytic and antimicrobial effects on multidrug-resistant (MDR) bacteria were investigated. The enzyme activity of E. faecalis BMSE-HMP 4 strains was measured, and it was found that the activities of esterase and esterase lipase were the highest. In addition, no hemolytic reaction was observed in any of the isolates. Subsequently, the anti-hemolytic activity against MDR strains causing hemolysis was evaluated. E. faecalis BMSE-HMP002 had the highest anti-hemolytic activity against Staphylococcus aureus CCARM 3855 at 75.71 ± 10.00%. The anti-hemolytic activity against Escherichia coli DC 2 CCARM 0238 and Pseudomonas aeruginosa CCARM 0223 showed that the activity of BMSE-HMP001 was highest at 76.92 ± 2.99% and 87.93 ± 1.93%, respectively. Examination of the antimicrobial effects against the MDR bacteria Staphylococcus spp., Escherichia spp., Pseudomonas spp., Salmonella spp., Klebsiella spp., Enterobacter spp., and E. faecalis BMSE-HMP strains showed antimicrobial effects against both gram-positive and gram-negative strains. Breastfeeding delivers enterococci into the intestinal tract of newborns by lactation, and its usefulness is attracting attention as it has been reported that enterococci have a potential effect on neonatal immune development. In this study, the hemolytic and antimicrobial effects of E. faecalis BMSE-HMP strains on MDR bacteria were investigated, to confirm their potential as useful lactic acid bacteria. Additional studies on the antibiotic resistance and toxicity of the E. faecalis BMSE-HMP strains, isolated in this study, are necessary to prove it safe for use.

• Journal of Food Hygiene and Safety
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• v.1 no.2
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• pp.143-149
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• 1986

Paraquat의 만성독성에 대한 vitamin E 급여의 효과를 조사하기 위하여 랫드에 paraquat를 50 ppm의 농도로 희석한 물을 음수 대신 투여하면서 vitamin E 함유 사료를 급여하여 paraquat에 대한 vitamin E의 방어 효과를 측정하였는 바 다음과 같은 결과를 얻었다. 1.혈장 vitamin E 농도는 사료 kg 당 10 mg까지의 vitamin E 함유 사료의 급여로 약 150$\mu\textrm{g}$/100ml까지 급격히 상승하였으며 그 후 급여량의 증가에도 비교적 안정된 혈중 농도를 유지하였고, 또한 paraquat 투여는 vitamin E 급여량에 관계없이 혈중 vitamin E 농도의 감소를 가져왔다. 2. 간저장 vitamin E 농도는 혈장 vitamin E 농도와 달리 급여량의 증가에 따라 비례하여 증가하는 경향을 보였으며 paraquat 투여에 의한 영향이 적었다. 3. Paraquat 투여는 적혈구 용혈율을 크게 증가시켰음 (95%), 100$\mu\textrm{g}$/100ml 이상의 vitamin E 혈장 농도에서는 안정된 적혈구 용혈율 (10% 이하)을 나타내었다. 4. Paraquat 투여는 혈장 trypsin inhibitor capacity를 크게 증가시켰으며, vitamin E 급여에 의하여 다소 회복되는 경향을 보였으나 정상에 이르지 못하였다. 5. 혈장 및 적혈구 glutathione peroxidase 활성은 paraquat 투여에 의하여 영향을 받지 않았다. 6. paraquat 투여 후의 lipid peroxide는 vitamin E의 급여로 감소되었다.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.258-266
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• 2014

Sweet potato soju (SPS), a form of traditional distilled alcoholic liquor in Korea, is manufactured by the distillation of fermented broth under normal pressure, thus providing it for a uniquely smooth taste infused with the flavor of sweet potato. After distillation, the lees of SPS is produced as by-product and discarded. In this study, the ethanol and hot water extracts of lees of SPS, and their subsequent organic solvent fractions using hexane, ethylacetate (EA), butanol, and water residue were prepared in an effort at the efficient re-use of the lees of SPS. The ethanol extraction yield was 1.36-fold higher than that of the hot water extraction, and the EA fraction revealed the highest total polyphenol content among the solvent fractions. The various extracts and solvent fractions did not demonstrate hemolytic activity at up to 0.5 mg/ml concentrations against human red blood cells. In the bioactivity assay, only the EA fraction displayed a broad spectrum of anti-microbial activity against different pathogenic and food spoilage bacteria, and demonstrated significant anti-coagulation activity by inhibitions of thrombin, prothrombin and blood coagulation factors. Furthermore, only the EA fraction from the hot water extract of the lees of SPS showed anti-platelet aggregation activity, which is comparable to aspirin (a commercially available drug). Our results suggest that the EA fraction of the hot water extract prepared from the lees of SPS has a high potential as a novel resource for anti-microbial and anti-thrombosis agents.

• KSBB Journal
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• v.7 no.4
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• pp.290-295
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• 1992

Reactive oxygen scavenging activity and immune stimulatory activity of lactobacilli were investigated by different free radical scavenging assays and Ig G assay. Lactobacilli culture (S/N) and its complex with $Mn^{2+}$ have significant effects in XOD assay and response to paraquat. Cell free extract significantly prevented the photohemolysis. Thus, it seems that each sample from lactobacilli has a different free radical scavening mechanism. Furthermore, it is assumed that cell free extract from lactobacilli activates antibody stimulation of B cell through a stimulation of T cell.

• Polymer(Korea)
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• v.35 no.5
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• pp.419-423
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• 2011

Chitosan is a natural polymer derived from chitin that has been widely used as a dietary supplement and in a variety of pharmacological and biomedical applications. In addition, water-soluble chitosan has been used to enhance the stability of chitosan in water and reduce cytotoxic activity induced by acetic acid. In this study, the antibiotic activity and mechanism of low molecular weight water-soluble chitosan (LMWSC; MW1, MW3, MW5, and MW10) were examined in pathogenic bacteria cells and vesicles containing bacterial membrane lipids. MW10 displayed potent antibacterial activity against pathogenic bacteria strains and no cytotoxicity against mammalian cells. In addition, the degree of calcein leakage was examined as a function of lipid composition (PE/PG=7/3 w/w). The results of these experiments demonstrated that MW10 promoted leakage in negatively-charged membranes. Furthermore, confocal microscopy revealed that MW10 was located in the plasma membrane.

• Journal of Life Science
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• v.34 no.3
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• pp.153-159
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• 2024

Dioscorea alata L, commonly known as "tropical yam" is the most widely consumed yam species among the 650 yam species belonging to the Dioscoreacea family. It is extensively cultivated in tropical and subtropical regions and is a major food source in Africa and India. Also, it is used for medicinal purposes, particularly in China and Taiwan, for its anti-inflammatory properties. In comparison to other yam varieties such as D. batatas or D. opposita, the tropical yam has gained popularity in Korea due to its higher yield per unit area. In this study, the nutritional characteristics and anti-thrombosis activity of the aerial bulbils of D. alata L. tropical yam were compared to those of D. opposita. The results showed that the aerial bulbils of tropical yam exhibited nutritional characteristics and potent anticoagulant activity compared to those of domestic yam varieties. The bulbils extract of tropical yam showed superior anticoagulant activities against thrombin, prothrombin and blood coagulation factors. Furthermore, the bulbils extract of tropical yam exhibited strong platelet aggregation inhibition at 0.25 mg/ml and showed no hemolytic activity up to a concentration of 2.5 mg/ml. These findings suggest the potential development of high-value anti-thrombosis agents utilizing the aerial bulbils of tropical yam.

• Journal of Environmental Science International
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• v.6 no.3
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• pp.225-229
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• 1997

A halophilic V. vulnificus is an estuarine microorganism that has been associated with fatal wound Infection and life-threatening septicemia. Hemolysin is defined as toxic substance produced by various species of bacteria Including V. vulnificus. Hemolysin from marine V. vulnificus was purified and the effect of pH, temperature. metal ion on the activity of hemolysin, and thermostability of hemolysin were tested in this study. Hemolysin iysed the sheep red blood cell and the optimum pH was 8.0, the optimum temperature was 4$0^{\circ}C$, and $K^+$ increased but $Mn^{2+}$ decreased the hemolyic activity of hemolysin, but hemolysin was unstable to heat.

• Journal of Life Science
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• v.22 no.5
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• pp.642-649
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• 2012

The southern coast of Korea is important for the ark shell ($Scapharca$ $broughtonii$) aquaculture, but the productivity was rapidly reduced during the previous decade by mass mortality. To overcome this economic loss, investigations only focused on environmental factors, and microbiological researches were performed insufficiently. In this study, two sites (Gangjin and Jinhae bay) were selected for their high and low rate of mortality, respectively, and the existence of microflora from underwater sediments in the bodies of $S.$ $broughtonii$ was analyzed. We screened the whole body of each sample and chose unique colonies, which exhibit alpha- and beta-hemolytic activity, for identification. The microflora in $S.$ $broughtonii$ was less variable than sediments, and restricted species were isolated. We identified 17 genera of 88 species and 16 genera of 64 species from the two bays, respectively. A major proportion was comprised of $Bacillus$ species, with the $Bacillus$ $cereus$ group being the most common species among the $Bacillus$ strains, while $Paenibacillus$, $Lynsilbacillus$, and $Vibrio$ species were the second most abundant species. At the genus level, there were no significant microbial differences between the two coastal regions. 64 species were isolated from rare site (Jinhae bay), but more species (88) with greater variety were isolated from the frequent site (Gangjin bay). Therefore, it was assumed that the cause of mass mortality lay in the difference in specie-level diversity, and conducting investigations on the diagnosis of pathogenic species by challenging tests using isolated unique species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.556-561
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• 1997

Vibrio cholerae non-O1 FM-3 was isolated from sea water, and it showed the same bacteriological characteristics as Vibrio cholerae non-O1 ATCC 25872. V. cholerae non-O1 FM-3 presented the highest hemolytic activity at stationary phase of its growth. The hemolytic activity was decreased in accordance with increasing of pretense activity of its cultural supernatant. The characteristics of the hemolysin produced by V. cholerae non-O1 FM-3 were investigated after partial purification with a Sephadex G-100 chromatography. The hemolytic activity of purified protein was stable at $4^{\circ}C$ while it was completely lost by heating at $60^{\circ}C$ for 30 min. The activity of hemolysin was increased by addition of divalent cations such as $Ca^{2+},\;Mg^{2+},\;and\;Mn^{2+}$ while it was inhibited by additions of $Zn^{2+}$. When the hemolysin was incubated with suspensions of erythrocytes at $4^{\circ}C$ and $37^{\circ}C$, respectively, hemolysis was not observed at $4^{\circ}C$ but at $37^{\circ}C$. It means that hemolysis by purified hemolysin was temperature-dependent while its binding step of hemolysin to cell membrane was temperature-independent.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.2
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• pp.61-67
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• 2007

In this study, the antioxidative effects of Equisetum arvense extracts were investigated. The free radical (1,1 diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$) of extract/fractions of Equisetum arvense was in the order: 50 % ethanol extract ($182.04{\mu}g/mL$) < ethylacetate fraction ($54.50{\mu}g/mL$) < deglycosylated flavonoid aglycone fraction ($14.13{\mu}g/mL$). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of some Equisetum arvense extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol- dependent chemiluminescence assay. The order of ROS scavenging activity was deglycosylated flavonoid aglycone fraction ($OSC_{50}$, $3.54{\mu}g/mL$) < 50 % ethanol extract ($0.80{\mu}g/mL$) < ethylacetate fraction ($0.006{\mu}g/mL$). Ethylacetate fraction showed the most prominent scavenging activity. The protective effects of extract/fractions of Equisetum arvense on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethanol extract (50%) suppressed photohemolysis in a concentration dependent manner, particularly deglycosylated aglycone extract exhibited the most prominent celluar protective effect ($\tau_{50}$, 161.10 min at $10{\mu}g/mL$). These results indicate that extract/fractions of Equisetum arvense can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS.