산화적 스트레스는 세포 및 조직 손상을 통해 피부의 탄력 및 보습 기능 저하, 피부 노화 촉진 을 비롯한 다양한 피부질환을 일으킨다. 본 연구의 목적은 인간 피부각질세포 (HaCaT keratinocyte)에서 산화적 스트레스에 대한 붉은 토끼풀 추출물의 효능을 검토하여, 피부에 효과적으로 사용할 수 있는 기능 성 소재로서의 활용 여부를 확인하고자 하였다. 본 연구에서는 붉은 토끼풀 추출물이 인간 피부각질세포에 서 산화적 스트레스에 따른 세포사를 억제시키는 것을 확인하여, 이를 조절하는 보호기전을 규명하였다. 이는 붉은 토끼풀 추출물이 Caspase-3 비활성, 세포사 촉진단백질 Bax 발현 억제, 세포생존 촉진단백질 Bcl-2 발현 증가 및 MAPK 신호전달계 단백질의 인산화 억제를 통해 H2O2에 의해 유도된 산화적 스트레 스를 보호할 수 있다는 것을 확인하였다. 따라서 붉은 토끼풀 추출물은 피부의 산화적 손상을 감소시키는 유용한 소재로 평가되며, 이는 피부보호 및 미용을 위한 다양한 제품 및 산업에 활용 가능성이 높은 것으로 판단된다.

Asparagus cochinchinensis is known to ameliorate respiratory disease. We evaluated the antimicrobial activity of non-fermented and fermented A. cochinchinensis using lactic acid bacteria and investigated the physicochemical characteristics of the fermented A.cochinchinensis. Non-fermented A.cochinchinensis showed lower levels of antimicrobial activity than the fermented A.cochinchinensis. Ethyl acetate (EtOAc) extracts of the fermented A. cochinchinensis showed antimicrobial activities against the indicator strains at lower minimum inhibitory concentration (MIC). The MIC of the EtOAc extract of non-fermented A. cochinchinensis against Escherichia coli, Staphylococcus epidermidis, and Stphylococcus aureus were 100, 75, and 100 mg/ml. In contrast, the MIC of the EtOAc extract of ACLM was 25 mg/mL against E. coli. The MIC of the EtOAc extract of ACLS was 12.5 mg/mL against S.epidermidis, and the MIC of the EtOAc extract ofACLP was 12.5 mg/mL against S.aureus. The viable cell number, pH, and acidity of A. cochinchinensis fermented by Lactobacillussakei 383 were similar to those of A. cochinchinensis fermented by Leuconostocmesenteroides 4395, but were different from those of A. cochinchinensis fermented by Lactobacillus.plantarum KCCM 11322. These results suggested that the fermented A. cochinchinensis by lactic acid bacteria may be a good candidate for application to ameliorate respiratory disease.

This study was carried out to find out the effect of water stress (RDI) on multiplication of plant parasitic nematodes on grapevines. The responses to irrigation treatments were not significantly different in relation to new root growth, root dry weight and total number of parasitic nematodes, however significant differences in the density of Meloidogyne javanica in the soil between daily irrigation and the treatment with water stress (RDI). The main effect of inoculum type was significant, and the water treatments significantly affected total root growth between the nematode treatments, as well as M. javanica density in the soil in the nematode treatments. The daily irrigation treatment with Pratylenchus spp. had the least root growth but was not significantly different to root growth in the RDI treatment with Pratylenchus spp. Similarly with RDI, there was no significant difference in root growth in treatments receiving combined nematode inoculum between daily irrigation and RDI. However, root growth in treatments receiving M. javanica in RDI was significantly greater than those receiving M. javanica with daily irrigation. Under RDI treatment, the number of M. javanica recovered from soil receiving M. javanica inoculum was significantly greater than under daily irrigation. However, there was no significant difference between daily irrigation and RDI in the number of M. javanica or Pratylenchus recovered from soil receiving the combined treatment or in Pratylenchus recovered from soil in the Pratylenchus treatment.

Lactic Acid Bacteria (LAB) are among the representative probiotics that have been used for a long time in fermented food. Although there are many studies on detecting the radical scavenging activity of LAB, few studies have been conducted on the environmental factors that improve scavenging activity. This study investigated the environmental factors affecting the DPPH radical scavenging and various antioxidant activities of Kimchi-derived Lactobacillus plantarum K-21 with antihypertensive and radical scavenging activities. The optimal conditions for scavenging DPPH radicals were glucose 2%, bactopeptone 0.5%, Tween 80 0.05%, L-cysteine 0.05%, and an initial pH 6.5 at 35℃. Under optimal conditions, the DPPH radical scavenging activity was 94.8±2.2%, which was 1.5 times higher than that of the basic medium. In addition, L. plantarum K-21 had other antioxidant activities; ABTS radical scavenging (93.6±1.5%), hydroxyl radical scavenging (8.5±0.9%), metal chelating (65.9±0.5%), NO scavenging (53.1±19%), SOD-like (25.1±1.5%), and reducing power (11.7±1.4%) activities were detected. Therefore, L. plantarum K-21 may act not only as a starter for lactic acid-fermented foods with improved functionality but also as a drug for various diseases caused by oxidative stress.

Lipoxygenase is an enzyme, mainly produced by plants, capable of converting unsaturated fatty acids to fatty acids. It has vast application potential in the food, pharmaceutical and agricultural industries. The aim of this study was to isolate novel lipoxygenase-producing bacteria from the environment and to investigate the lipoxygenase enzymatic properties for industrial production. The strain, NC1, isolated from cultivation soils, was identified as Bacillus subtilis based on the phenotypic characteristics and 16S rRNA gene sequencing. This strain formed a pink color around the colony when cultured on indamine dye formation plates. The production of lipoxygenase by B. subtilis NC1 was influenced by the composition of the medium and linoleic acid concentrations. The optimum temperature and pH for lipoxygenase activity was determined to be 40 °C and pH 6, respectively. The enzyme showed relatively high stability at temperatures ranging from 20–50 °C and acid-neutral regions. In addition, the lipoxygenase produced by B. subtilis NC1 was able to degrade commercially available oils including sunflower seed oil and Perilla oil. In this study, a useful indigenous bacterium was isolated, and the fundamental physicochemical data of bacterial lipoxygenase giving it industrial potential are presented.

To develop eco-friendly microbial inoculants, siderophore-producing bacteria were isolated and identified, and their production characteristics and plant growth-promoting abilities were investigated. A strain S21 was isolated from rhizosphere of Korean perilla (Perilla frutescens) and identified as Enterobacter amnigenus by phenotypic properties and 16S rRNA gene sequencing. The highest siderophore production was obtained in a medium containing 0.5% fructose, 0.1% urea, 0.5% K2HPO4 and 0.1% succinic acid. By using this improved medium, siderophore production increased by 2.5 times compared to that of basal medium. The strain S21 showed insoluble phosphate solubilizing, ammonification and antifungal activities, and also produced hydrolytic enzymes (protease and lipase), indoleacetic acid and 1-aminocyclopropane-1-carboxylate deaminase. Our data suggest that E. amnigenus S21 is a potential candidate that can be used as eco-friendly biocontrol agent and biofertilizer.

Production of Bacterial Cellulose (BC) by Gluconacetobacter sp. A5 was studied in shaken culture using different cost-effective carbon sources and its structural and mechanical properties were evaluated. Glycerol showed the highest level (7.26 g/l) of BC production, which was about three times higher than the yield in glucose medium. BC production depended not only on the decrease in pH, but also on the ability of Gluconacetobacter sp. A5 to synthesize glucose from different carbon sources and then polymerize it into BC. All BC produced from different carbon sources exhibited a three-dimensional reticulated structure consisting of ultrafine cellulose fibriles. Carbon sources did not significantly change the microfibrile structure of the resulting BC. BC produced from glucose medium had the lowest water-holding capacity, while BC from molasses medium had the highest. XRD data revealed that all BC were cellulose type І, the same as typical native cellulose. The crystalline strength of BC produced in glucose medium was the highest, and that in molasses medium was the lowest. Our results suggest that glycerol could be a potential low-cost substrate for BC production, leading to the reduction in the production cost, and also to produce BC with different mechanical properties by selecting appropriate carbon source.

To develope a microbial weed control agent, HCN-producing bacteria were isolated, and their characteristics were investigated. A selected strain of WA15 was identified as Pseudomonas koreensis by morphological, cultural, biochemical and 16S rRNA gene analyses. The conditions for HCN production was investigated by a One-Variable-at-a-Time (OVT) method. The optimal HCN production conditions were tryptone 1%, glycine 0.06%, NaCl 1% , and an initial pH and temperature of 5.0 and 30℃, respectively. The major component for HCN production was glycine. Under optimal conditions, HCN production was about 3 times higher than that of the basal medium. The WA15 strain had physiological activities, such as indoleacetic acid that was associated with the elongation of plant roots and siderophore and ammonification inhibiting fungal growth, and produced hydrolytic enzymes, such as cellulase, pectinase and lipase. The strain was able to inhibit the growth of phytopathogenic fungi, such as Rhizoctonia solani, Botrytis cinerea and Fusarium oxysporum, by the synergistic action of volatile HCN and diffusible antimicrobial compounds. A microscopic observation of R. solani that was teated with the WA15 strain showed morphological abnormalities of fungal mycelia, which could explain the role of the antimicrobial metabolites that were produced by the WA15 strain. The volatile HCN produced by the WA15 strain was also found to have insecticidal activity against termites. Our results indicate that Pseudomonas koreensis WA15 can be applied as a microbial agent for weed control and also as a termite repellent. Furthermore, it could be applied as a microbial termiticidal agent to replace synthetic insecticides.

The objective of this study was to investigate the adsorption potential of chicken feathers for the removal of OrangeⅡ (AO7) from aqueous solutions. Batch experiments were performed as a function of different experimental parameters such as initial pH, reaction time, feather dose, initial OrangeⅡ concentration and temperature. The highest OrangeⅡ uptake was observed at pH 1.0. Most of the OrangeⅡ was adsorbed at 2 h and an adsorption equilibrium was reached at 6 h. As the amount of chicken feather was increased, the removal efficiency of Orange II increased up to 99%, but its uptake decreased. By increasing the initial concentration and temperature, OrangeⅡ uptake was increased. The experimental adsorption isotherm exhibited a better fit with the Langmuir isotherm than with the Freundlich isotherm, and maximum adsorption capacity from the Langmuir constant was determined to be 0.179244 mmol/g at 30℃. The adsorption energy obtained from the Dubinin-Radushkevich model was 7.9 kJ/mol at 20℃ and 30℃ which indicates the predominance of physical adsorption. Thermodynamic parameters such as ΔGo, ΔHo, and ΔSo were -12.28 kJ/mol, 20.64 kJ/mol and 112.32 J/mol K at 30℃, respectively. This indicates that the process of OrangeⅡ adsorption by chicken feathers was spontaneous and endothermic. Our results suggest that as a low-cost biomaterials, chicken feather is an attractive candidate for OrangeⅡ removal from aqueous solutions.

Lactic acid bacteria (LAB) are industrially important microorganisms for probiotics. The recent widespread application of LAB for preparation of functional food is attributable to the accumulating scientific evidence showing their beneficial effects on human health. In this study, we isolated and characterized plant-derived LAB that show angiotensin-converting enzyme (ACE) inhibitory and antioxidant activities. The selected strain K2 was isolated from Kimchi, and identified as Lactobacillus plantarum by 16S rRNA gene analysis. The strain grew under static and shaking culture systems. They were also able to grow in different culture conditions like 25℃∼37℃ temperature, 4∼10 pH range and ∼6% NaCl concentration. L. plantarum K2 was highly resistant to acid stress; survival rate of the strain at pH 2.5 and 3 were 80% and 91.6%, respectively. The strain K2 also showed high bile resistance to 0.3% bile bovine and 0.3% bile extract with more than 74% of survival rate. The cell grown on MRS agar plate containing bile extract formed opaque precipitate zones around the colonies, indicating they have bile salt hydrolase activity. The strain showed an inhibitory activity against pathogenic bacteria such as Escherichia coli, Staphylococcus aureus and Listeria monocytogenes; antibacterial activity was probably due to the lactic acid. The K2 strain showed relatively higher autoaggregation values, antihypertensive and antioxidant activities. These results suggest that L. plantarum K2 could be not only applied as a pharmabiotic for human health but also is also starter culture applicable to fermentative products.

Styela clava tunic is generated in large amounts as a waste from S. clava processing plants and leads to environmental problems. It destroys the beach scenery and causes a bad smell and pollution by trashing on the seashore. Therefore, purpose of this study was to investigate antioxidant and antihypertensive activities of different solvent extracts from S. clava tunic for recycling of fishery waste. Antioxidant and antihypertensive activities of all extracts were concentration-dependent. Of extracts, hot water extract showed the highest DPPH radical scavenging activity with the lowest effective concentration (EC50) value (0.733 mg/ml). Chloroform extract exhibited the highest metal chelation activity with the lowest EC50 value (2.696 mg/ml). Autoclaved water extract showed the highest NO radical scavenging activity with the lowest EC50 value (0.491 mg/ml) and n-hexane extract showed the highest reducing power (A700=1.897 at 100 mg/ml). And n-butanol extract showed the highest SOD-like activity with the lowest EC50 value (19.116 mg/ml) and ACE inhibition activity with the lowest inhibitory concentration(IC50) value (0.149 mg/ml). These results indicate that extracts obtained from S. clava tunic may potential candidate to reduce diseases caused by various oxidative stresses and hypertension.

Keratin wastes are generated in excess of million tons per year worldwide and biodegradation of keratin by microorganisms possessing keratinase activity can be used as an alternative tool to prevent environmental pollution. For practical use of keratinase, its physicochemical properties should be investigated in detail. In this study, we investigated characteristics of keratinase produced by Xanthomonas sp. P5 which is isolated from rhizospheric soil of soybean. The level of keratinase produced by the strain P5 increased with time and reached its maximum (10.6 U/ml) at 3 days. The production of soluble protein had the same tendency as the production of keratinase. Optimal temperature and pH of keratinase were 40℃-45℃ and pH 9, respectively. The enzyme showed broad temperature and pH stabilities. Thermostability profile showed that the enzyme retained 94.6%-100% of the original activity after 1 h treatment at 10℃-40℃. After treatment for 1 h at pH 6-10, 89.2%-100% of the activity was remained. At pH 11, 71.6% of the original activity was retained after 1 h treatment. Although the strain P5 did not degrade human hair, it degraded duck feather and chicken feather. These results indicate that keratinase from Xanthomonas sp. P5 could be not only used to upgrade the nutritional value of feather hydrolysate but also useful in situ biodegradation of feather.

Bacterial cellulose (BC) has played important role as new functional material for food industry and industrial products based on its unique properties. The interest in BC from static cultures has increased steadily in recent years because of its potential for use in medicine and cosmetics. In this study, we investigated culture condition for BC production by Acetobacter sp. F15 in static culture. The strain F15, which was isolated from decayed fruit, was selected on the basis of BC thickness. The optimal medium compositions for BC production were glucose 7%, soytone 12%, K2HPO4 0.2%, NaH2PO4ㆍ2H2O 0.2%, lactic acid 0.05% and ethanol 0.3%, respectively. The strain F15 was able to produce BC at 26℃-36℃ with a maximum at 32 ℃. BC production occurred at pH 4.5-8 with a maximum at pH 6.5. Under these conditions, a maximum BC thickness of 12.15 mm was achieved after 9 days of cultivation; this value was about 2.3-fold higher than the thickness in basic medium. Scanning electron micrographs showed that BC from the optimal medium was more compact than plant cellulose and was reticulated structure consisting of ultrafine cellulose fibrils. BC from the optimal medium was found to be of cellulose type I, the same as typical native cellulose.

Styela clava tunic is generated in large amounts as a waste from S. clava processing plants and causes environmental problem. Although biological activities of S. clava were reported by many investigators, study on S. clava tunic was little. In this study, therefore, tyrosinase inhibition and antioxidative activities of extracts from S. clava tunic using different solvent were investigated for recycling of the fishery waste. Among extraction methods tested, autoclaved extraction (25.7%) and hot water extraction (18.2%) appeared to be effective for extraction. The highest total phenolic content was 46.6 mg/g in autoclaved extract while the highest flavonoid content was 23.0 mg/g in chloroform extract. All extracts possessed tyrosinase inhibition activity and the inhibition activity was concentration-dependent. Inhibition concentration (IC50) against tyrosinase activity was 0.36×104 mg/ml in ethanol extract, 0.11×103 mg/ml in acetone extract and 0.27 mg/ml in n-butanol extract. Among extracts tested, hot water and autoclaved extracts displayed higher antioxidative activity than organic solvent extracts. Therefore, our data suggest that extract from S. clava tunic may potential candidate for cosmetic product with whitening effect and medicine for diseases caused by various oxidative stresses.

We investigated the optimal conditions for keratinase production by feather-degrading Pseudomonas geniculata H10 using one variable at a time (OVT) method. The optimal medium composition and cultural condition for keratinase production were determined to be glucose 0.15% (w/v), beef extract 0.08% (w/v), KH2PO4 0.12% (w/v), K2HPO4 0.02% (w/v), NaCl 0.07% (w/v), MgSO4․7H2O 0.03%, MgCl2․6H2O 0.04% along with initial pH 10 at 200 rpm and 25℃, respectively. The production yield of keratinase was 31.6 U/ml in an optimal condition, showing 4.6-fold higher than that in basal medium. The strain H10 also showed plant growth promoting activities. This strain had ammonification activity and produced indoleacetic acid (IAA), siderophore and a variety of hydrolytic enzymes such as protease, lipase and chitinase. Therefore, this study showed that P. geniculata H10 could be not only used to upgrade the nutritional value of feather wastes but also useful in situ biodegradation of feather wastes. Moreover, it is also a potential candidate for the development of biofertilizing agent applicable to crop plant soil.

Gamma amino butyric acid (GABA), known as a non-protein amino acid and major inhibitory neurotransmitter in the brain, has several functional properties such as neurotransmission, induction of hypotension, tranquilizer, and diuretic effects. The purpose of this study was to isolate and identify lactic acid bacteria, producing high GABA in fermented soy curd. Thirty-two strains of tofu-forming lactic acid bacteria were isolated from kimchi which a traditional Korean food fermented with many kind of microorganism. Among 32 strains, four strains (strain No. 10, 104, 214, 249) formed firm soycurd. In order to select lactic acid bacteria having high GABA producing potential, the isolated strains were cultured in the soymilk and fermented for 48 hr at 37℃. A strain No. 383, which showed highest GABA contents in fermented soycurd, was identified as L. sakei by 16S rDNA sequencing and API analysis, and named as L. sakei 383. L. sakei 383 showed optimal growth up to 24 hr at 35℃ in MRS broth. The optimal time and temperature for GABA production were 18 hr and 35°C in soymilk. In the optimal condition time and temperature, GABA content of fermented soycurd by L. sakei 383 was 8.65 mg/100 g.

Although antioxidant activities of Korean traditional fermented foods were reported by many researchers, study on antioxidant activity of microorganism originated from Korean traditional fermented foods was little. Therefore, we improved condition for antioxidant production by a bacterium isolated from home-made Chungkookjang. We selected a bacterial strain, which showed the highest antioxidative activity, from Chungkookjang and then named GJ. The selected GJ strain was identified as Bacillus methylotrophicus by alignment data of 16S rRNA gene nucleotide sequences. Improved medium compositions for DPPH radical scavenging activity were 0.25% sucrose, 1% peptone, 0.01% MgSO4·7H2O and initial pH 6.5, respectively. Optimal culture conditions were 30℃, 200 rpm and 4% inoculum volume, respectively. In improved conditions, DPPH radical scavenging activity of GJ reached to 91% in a short time. The strain GJ also possessed ACE inhibition and other antioxidative activities; ACE inhibition activity (49.4%), ABTS radical scavenging activity (99.8%), metal chelating activity (67.9%), SOD-like activity (36.5%) and reducing power (A700 = 5.982) were observed, respectively. Therefore, our results suggest that B. methylotrophicus GJ strain may be potential candidate for functional foods, cosmetic products for anti-aging and medicine for diseases caused by oxidative stress.

This study was carried out to investigate changes of protease and amylase activities and nitrogen content in Chungkookjang prepared by Bacillus subtilis S8 and different soybean. Amino-type nitrogen and ammonia-type nitrogen contents increased with an increase in fermentation time and was the highest in black soybean Chungkookjang. The number of viable cells increased up to 24 h of fermentation at all temperatures tested; especially, their levels were the highest at 40℃. Protease activity was the highest in black soybean Chungkookjang. α-amylase activity increased significantly up to 6 h of fermentation at 30℃and 40℃and then maintained constantly. It also increased up to 30-36 h of fermentation at 45℃and then decreased. β -amylase activity was the highest in black soybean Chungkookjang at 35℃and 40℃and in yellow soybean Chungkookjang at 45℃. Production pattern of reducing sugar was similar to that of β-amylase. Amino-type nitrogen, viable cell number and reducing sugar content and β-amylase activity was the highest in Chungkookjang fermented at 40℃. Considering amino-type and ammonia-type nitrogen contents, Chungkookjang fermentation using yellow soybean was favorable. However, the fermentation using black soybean was favorable, considering protease and amylase activities and reducing sugar content.

We investigated usefulness of chicken feather as bioadsorbent for removal of hexavalent chromium[Cr(Ⅵ)] and oil from aqueous solution. Chicken feather was chemically treated with DTPA, EDTA, NaOH and SDS, respectively. Among them, EDTA was the most effective in adsorbing Cr(Ⅵ). Cr(Ⅵ) uptake by chicken feather was increased with decreasing pH; the highest Cr(Ⅵ) uptake was observed at pH 2.0. By increasing Cr(Ⅵ) concentration, Cr(Ⅵ) uptake was increased, and maximum Cr(Ⅵ) uptake was 0.34 mmol/g. Cr(Ⅵ) adsorption by chicken feather was well described by Freundlich isotherm than Langmuir isotherm and Freundlich constant(1/n) was 0.476. As the concentration of chicken feather was increased, Cr (Ⅵ) removal efficiency was increased but Cr(Ⅵ) uptake was decreased. Most of Cr(Ⅵ) was adsorbed at early reaction stage(1 h) and adsorption equilibrium was established at 5 h. On the other hand, chicken feather adsorbed effectively oils including bunker-A and bunker-C. In conclusion, our results suggest that chicken feather waste could be used to remove heavy metal and oil; it is a potential candidate for biosorption material.

We isolated and characterized novel duck feather-degrading bacteria producing keratinase. Twelve strains were isolated from soil and faces at poultry farm, and decayed feathers. They were identified as Bacillus methylotrophicus, Pseudomonas geniculata, Pseudomonas hibiscicola, Exiquobacterium profundum, Bacillus pumilus, Bacillus amyloliquefaciens, Chryseobacterium indologenes, Bacillus thuringiensis, Thermomonas koreensis, respectively, by phenotypic characters and 16S rRNA gene analysis. Generally, the level of keratinase production was not proportional to feather degradation rate. The highest keratinolytic activity was observed in the culture inoculated with Chryseobacterium indologenes D27. Although all strains did not degrade human hair, strains tested effectively degraded chicken feather(53.8-91.4%), wool(40.4-93.0%) and human nail (51.0-82.9%). These results suggest that strains isolated could be not only used to improve the nutritional value of recalcitrant feather waste but also is a potential candidate for biotechnological processes of keratin hydrolysis.