• Preventive Nutrition and Food Science
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• 제13권4호
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• pp.313-320
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• 2008

Efficiency of a far-infrared radiation (FIR) dryer for drying of citrus by-products (CBPs) was evaluated through their antioxidant activities. The CBPs dried through FIR were enzymatically digested by six carbohydrases (AMG, Celluclast, Pectinase, Termamyl, Ultraflo and Viscozyme) to prepare digests for evaluation of the activities. The total polyphenolic and total flavonoid contents of the digests were determined by colorimetric assays. The AMG digest was selected for the further experiments. The antioxidant potential of the digests were evaluated by DPPH, superoxide, hydroxyl and alkyl radical scavenging activities, $H_2O_2$ scavenging activity, metal chelating, lipid peroxidation inhibition and the reduction of DNA damage. The AMG digest from CBPs dried through FIR at $50^{\circ}C$ showed strong antioxidant activities in DPPH, superoxide, hydrogen peroxide, alkyl and metal chelating assays while all the digests showed strong lipid peroxidation activities. Further, enzymatic digests showed remarkable inhibitory activities against $H_2O_2$-induced DNA damage. Hence, the data obtained using different in vitro models clearly established the antioxidant potential of enzymatic digests from CBPs dried through FIR. Furthermore, they can be used as a source of natural antioxidants; hence, far-infrared radiation drying is a viable method for transforming wet CBPs into a dried form without destroying the bioactive components.

• Asian-Australasian Journal of Animal Sciences
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• 제15권12호
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• pp.1725-1731
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• 2002

The distribution and activities of hydrolytic enzymes (cellulolyti, hemicellulolytic,pectinolytic and others) in the rumen compartments of Hereford bulls fed 100% alfalfa hay based diets were evaluated. The alfalfa proportion in the diet was gradually increased for two weeks. Whole rumen contents were processed into four fractions: Rumen contents including both the liquid and solid fractions were homogenized and centrifuged, and the supernatant was assayed for enzymes located in whole rumen contents (WRE); rumen contents were centrifuged and the supernatant was assayed for enzymes located in rumen fluids (RFE); feed particles in rumen contents were separated manually, washed with buffer, resuspended in an equal volume of buffer, homogenized and centrifuged and supernatant was assayed for enzymes associated with feed particles (FAE); and rumen microbial cell fraction was separated by centrifugation, suspended in an equal volume of buffer, sonicated and centrifuged, and the supernatant was assayed for enzymes bound with microbial cells (CBE). It was found that polysaccharide-degrading proteins such as $\beta$-1,4-D-endoglucanase, $\beta$-1,4-D-exoglucanase, xylanase and pectinase enzymes were located mainly with the cell bound (CBE) fraction. However, $\beta$-D-glucosidase, $\beta$-D-fucosidase, acetylesterase, and $\alpha$-L-arabinofuranosidase were located in the rumen fluids (RFE) fraction. Protease activity distributions were 37.7, 22.1 and 40.2%, and amylase activity distributions were 51.6, 18.2 and 30.2% for the RFE, FAE and CBE fractions, respectively. These results indicated that protease is located mainly in rumen fluid and with microbial cells, whereas amylase was located mainly in the rumen fluid.

• 한국균학회지
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• 제14권3호
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• pp.189-194
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• 1986

한국산 표고균(菌)의 생리적 조사의 일원으로서 이 균주(菌株)가 목재에서 생장시 필요로하는 목재분해 효소들의 특징 및 생성경향을 조사하였다. 각 효소들의 유도를 위한 배지로서는 각각 단일의 특정탄소원을 첨가한 배지를 사용하였고 이때 추출한 조효소를 효소용액으로 사용하였으며 이들 효소에 대한 최적온도 및 최적 pH등의 조건을 조사하였다. 또한 이 균주가 목재구성성분을 분해하는 기작을 간접적으로 추정하기 위하여 복합배지 및 통방배지 내에서의 각 효소생성 양상을 측정하였다. 이 균주가 목재성분을 분해할 때에는 cellulose와 hemicellulose의 하나인 xylan을 초기에 분해하여 이용하고, 조금지나서 pectin 질을 분해함을 알수있었다. 또한 이들기질들은 서로 상호작용에 의해 분해가 좀더 원활하게 이루어지게 하는데 효과가 있었다.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1577-1584
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• 2010

In total, 140 halotolerant bacterial strains were isolated from both the soil of barren fields and the rhizosphere of six naturally growing halophytic plants in the vicinity of the Yellow Sea, near the city of Incheon in the Republic of Korea. All of these strains were characterized for multiple plant growth promoting traits, such as the production of indole acetic acid (IAA), nitrogen fixation, phosphorus (P) and zinc (Zn) solubilization, thiosulfate ($S_2O_3$) oxidation, the production of ammonia ($NH_3$), and the production of extracellular hydrolytic enzymes such as protease, chitinase, pectinase, cellulase, and lipase under in vitro conditions. From the original 140 strains tested, on the basis of the latter tests for plant growth promotional activity, 36 were selected for further examination. These 36 halotolerant bacterial strains were then tested for 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity. Twenty-five of these were found to be positive, and to be exhibiting significantly varying levels of activity. 16S rRNA gene sequencing analyses of the 36 halotolerant strains showed that they belong to 10 different bacterial genera: Bacillus, Brevibacterium, Planococcus, Zhihengliuella, Halomonas, Exiguobacterium, Oceanimonas, Corynebacterium, Arthrobacter, and Micrococcus. Inoculation of the 14 halotolerant bacterial strains to ameliorate salt stress (150 mM NaCl) in canola plants produced an increase in root length of between 5.2% and 47.8%, and dry weight of between 16.2% and 43%, in comparison with the uninoculated positive controls. In particular, three of the bacteria, Brevibacterium epidermidis RS15, Micrococcus yunnanensis RS222, and Bacillus aryabhattai RS341, all showed more than 40% increase in root elongation and dry weight when compared with uninoculated salt-stressed canola seedlings. These results indicate that certain halotolerant bacteria, isolated from coastal soils, have a real potential to enhance plant growth under saline stress, through the reduction of ethylene production via ACC deaminase activity.

• 한국염색가공학회지
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• 제8권1호
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• pp.64-72
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• 1996

To develop a scouring method for the high-grade quality and the high value added of flax for spinning, it was measured and analyzed weight loss and degree of injury with change of scouring concentration, time, temperature and pH. We got the f ollowing results; Firstly, in case that flax was scoured at a fixed condition, the weight loss and degree of injury of scoured flax under the no-cutting condition were lower than that of scoured flax under the cutting condition. Secondly, when flax was scoured with $Na_{2}CO_{3}$, it was obtained that the higher weight loss and degree of injury and weight loss with the increase of scouring time and condition. The degree of injury was lower than any other under the treatment condition of 4% $Na_{2}CO_{3}$concentraion for 2 hours. Finally, when alkaline scoured flax was rescoured by pectinase, enzyme activation effect was the most active under the treatment condition of pH 4 for 2 hours. The scouring effect was better than that of alkaline scouring only.

• 생명과학회지
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• 제6권2호
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• pp.94-103
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• 1996

To understand effect of inoculum size, cell density, sucrose concentration and concentrations of MS basal on suspension culture and protoplast isolation of wild viola(Viola patrinii DC.) callus from petiole segments this experiment was conducted. In the lot of 30 mesh inoculum size, two observations were; One was that a considerable increase in the fresh and dry weight of callus was determined. Another was that the callus mass was relatively compact compared with others. A recommendable cell density was 0.4g for 20ml culture medium and the higher sucrose concentration, the higher fresh and dry weight were obtained. The dilution of MS basal salt was differently affected on fresh and dry weight; the highest fresh weight was found in 1x MS salt, while the higest dry weight was in 1/3x dilution.The addition of casein hydrolysate(3g/L) was more effective to increase of both fresh and dry weight. THe contents of protein was great in the inoculum lots with larger inoculum sizeand higher concentration of MS basal salts contenting 3g/L of casein hydrolysate and higher sucrose compared with others. The greatest protoplasts were isolated from the lot of 10 mesh size treated with 1%pectinase SE-150 and 2% cellulase YC. In general, for optimal protoplast isolation the followingconditions were recommended; 1) Use of smaller cell size cultured for 2-5 weeks, and 2) more than 5 hours incubation using the combined mixture of the enzymes with proper concentrations.

• Journal of Microbiology
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• 제45권5호
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• pp.394-401
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• 2007

In this study, bacterial communities within the guts of several longicorn beetles were investigated by a culture-dependent method. A total of 142 bacterial strains were isolated from nine species of longicorn beetle, including adults and larvae. A comparison of their partial 16S rRNA gene sequences showed that most of the bacteria constituting the gut communities can typically be found in soil, plants and the intestines of animals, and approximately 10% were proposed as unreported. Phylogenetic analysis demonstrated that the bacterial species comprised 7 phyla, and approximately half were Gammaproteobacteria. Actinobacteria were the second most populous group (19%), followed by Firmicutes (13%) and Alphaproteobacteria (11%). Betaproteobacteria, Flavobacteria, and Acidobacteria were minor constituents. The taxonomic compositions of the isolates were variable according to the species of longicorn beetle. Particularly, an abundance of Actinobacteria existed in Moechotypa diphysis and Mesosa hirsute, which eat broadleaf trees; however, no Actinobacteria were isolated from Corymbia rubra and Monochamus alternatus, which are needle-leaf eaters. Considerable proportions of xylanase and pectinase producing bacteria in the guts of the longicorn beetles implied that the bacteria may play an important role in the digestion of woody diets. Actinobacteria and Gammaproteobacteria were the dominant xylanase producers in the guts of the beetles.

• Journal of Microbiology and Biotechnology
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• 제20권12호
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• pp.1614-1623
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• 2010

Bacteria were isolated from roots of sugarcane varieties grown in the fields of Punjab. They were identified by using API20E/NE bacterial identification kits and from sequences of 16S rRNA and amplicons of the cpn60 gene. The majority of bacteria were found to belong to the genera of Enterobacter, Pseudomonas, and Klebsiella, but members of genera Azospirillum, Rhizobium, Rahnella, Delftia, Caulobacter, Pannonibacter, Xanthomonas, and Stenotrophomonas were also found. The community, however, was dominated by members of the Pseudomonadaceae and Enterobacteriaceae, as representatives of these genera were found in samples from every variety and location examined. All isolates were tested for the presence of five enzymes and seven factors known to be associated with plant growth promotion. Ten isolates showed lipase activity and eight were positive for protease activity. Cellulase, chitinase, and pectinase were not detected in any strain. Nine strains showed nitrogen fixing ability (acetylene reduction assay) and 26 were capable of solubilizing phosphate. In the presence of 100 mg/l tryptophan, all strains except one produced indole acetic acid in the growth medium. All isolates were positive for ACC deaminase activity. Six strains produced homoserine lactones and three produced HCN and hexamate type siderophores. One isolate was capable of inhibiting the growth of 24 pathogenic fungal strains of Colletotrichum, Fusarium, Pythium, and Rhizoctonia spp. In tests of their abilities to grow under a range of temperature, pH, and NaCl concentrations, all isolates grew well on plates with 3% NaCl and most of them grew well at 4 to $41^{\circ}C$ and at pH 11.

• 한국양식학회지
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• 제12권1호
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• pp.7-14
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• 1999

갈래곰보의 원혈질체 분리와 배양 조건을 확립하여 생명공학기술에 의한 유전적 형질개량의 기초조건을 마련코자 하였다. Abalone acetone powder,소라의 내장조효소, Pseudomanas와 Vibrio의 조효소, Cellulas R-10, Macerozyme R-10, Hemicellulase, Pectinase, Driselase, Protease 등을 0.6M mannitol과 0.5% potassium dextran sulfate를 함유한 50mM MES 해수완충액(pH 6.0)에 단독 또는 조합하여 조제한 효소액을 갈래곰보의엽체에 처리하였을 때 Abalone acetone powder 4.0% + Macerozyme R-10 4.0% + Hemicellulase 4.0% 효소조합액의 처리로서 생체조직 1g당 $107.6{\times}10^4$개의 원혈질체를 분리시킬 수 있었다. 갓 분리한 원형질체는 투명한 타원형으로 $7{\mu} m$~ $24{\mu} m$의 범위에 분포하였다. 0.2M mannitol을 첨가한 $ASP_{12}$배지에 배양한 세포는 9일 후 분열되고 25일 후 발아하였다. $ASP_{12}$배지는 f/2배지보다 갈래 곰보의 원혈질체 배양에 효과적이었으며 Guillard 항생물질조합액의 처리는 분화에 장애가 되었다.

• Mycobiology
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• 제43권4호
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• pp.458-466
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• 2015

Oak tree death caused by symbiosis of an ambrosia beetle, Platypus koryoensis, and an ophiostomatoid filamentous fungus, Raffaelea quercus-mongolicae, has been a nationwide problem in Korea since 2004. In this study, we surveyed the yeast species associated with P. koryoensis to better understand the diversity of fungal associates of the beetle pest. In 2009, a total of 195 yeast isolates were sampled from larvae and adult beetles (female and male) of P. koryoensis in Cheonan, Goyang, and Paju; 8 species were identified by based on their morphological, biochemical and molecular analyses. Meyerozyma guilliermondii and Candida kashinagacola were found to be the two dominant species. Among the 8 species, Candida homilentoma was a newly recorded yeast species in Korea, and thus, its mycological characteristics were described. The P. koryoensis symbiont R. quercusmongolicae did not show extracelluar CM-cellulase, xylanase and avicelase activity that are responsible for degradation of wood structure; however, C. kashinagacola and M. guilliermondii did show the three extracellular enzymatic activities. Extracelluar CM-cellulase activity was also found in Ambrosiozyma sp., C. homilentoma, C. kashinagacola, and Candida sp. Extracelluar pectinase activity was detected in Ambrosiozyma sp., C. homilentoma, Candida sp., and M. guilliermondii. All the 8 yeast species displayed compatible relationships with R. quercus-mongolicae when they were co-cultivated on yeast extract-malt extract plates. Overall, our results demonstrated that P. koryoensis carries the yeast species as a symbiotic fungal associate. This is first report of yeast diversity associated with P. koryoensis.