1.Detection of Extracellular Enzyme Activity in Penicillium using Chromogenic Media.
Ji Hwan YOON ; Seung Beom HONG ; Seung Ju KO ; Seong Hwan KIM
Mycobiology 2007;35(3):166-169
A total of 106 Penicillium species were tested to examine their ability of degrading cellobiose, pectin and xylan. The activity of beta-glucosidase was generally strong in all the Penicillium species tested. P. citrinum, P. charlesii, P. manginii and P. aurantiacum showed the higher ability of producing beta-glucosidase than other tested species. Pectinase activity was detected in 24 Penicillium species. P. paracanescens, P. sizovae, P. sartoryi, P. chrysogenum, and P. claviforme showed strong pectinase activity. In xylanase assay, 84 Penicillium species showed activity. Strong xylanase activity was detected from P. megasporum, P. sartoryi, P. chrysogenum, P. glandicola, P. discolor, and P. coprophilum. Overall, most of the Penicillium species tested showed strong beta-glucosidase activity. The degree of pectinase and xylanase activity varied depending on Penicillium species.
beta-Glucosidase
;
Cellobiose
;
Penicillium*
;
Polygalacturonase
2.Detection of Extracellular enzymes Activities in Various Fusarium spp..
Hyuk Woo KWON ; Ji Hwan YOON ; Seong Hwan KIM ; Seung Beom HONG ; Youngah CHEON ; Seung Ju KO
Mycobiology 2007;35(3):162-165
Thirty seven species of Fusarium were evaluated for their ability of producing extracellular enzymes using chromogenic medium containing substrates such as starch, cellobiose, CM-cellulose, xylan, and pectin. Among the tested species Fusarium mesoamericanum, F. graminearum, F. asiaticum, and F. acuminatum showed high beta-glucosidase acitivity. Xylanase activity was strongly detected in F. proliferatum and F. oxysporum. Strong pectinase activity was also found in F. oxysporum and F. proliferatum. Amylase activity was apparent in F. oxysporum. No clear activity in cellulase was found from all the Fusarium species tested.
Amylases
;
beta-Glucosidase
;
Cellobiose
;
Cellulase
;
Fusarium*
;
Polygalacturonase
;
Starch
3.Isolation and identification of Vibrio vulnificus and Vibrio parahaemolyticus from coast of Pusan and Daechon.
Jin Woo JU ; Min Jung PARK ; Moon Soo HEO ; Cho Rok JUNG
Journal of the Korean Society for Microbiology 2000;35(4):309-316
This study was focused on the isolation of pathogenic Vibrio species, V. vulnificus and V. parahaemolyticus from marine environment from May to July of 1999. Isolation sites were coast near by Pusan and Daechon. The results obtained were as follows: 1. Seventy strains of V. parahaemolyticus and 19 strains of V. vulnificus were isolated from a total of 120 specimens. 2. Nineteen strains of V. vulnificus did not fermented arabinose and salicin but fermented lactose and cellobiose. All of V. parahaemolyticus isolates did not fermented lactose and cellobiose. 47 strains of V. parahaemolyticus fermented arabinose but 53 strains did not fermented salicin. 3. V. vulnificus and V. parahaemolyticus isolates showed three different API index numbers with 5046105 and 4346107 dominant. 4. V. vulnificus did not grow on 0% and 8% NaCl containing medium. V. parahaemolyticus grew on 8% NaCl containing medium. 5. V. vulnificus isolates and V. parahaemolyticus revealed different outer membrane protein p rofiles on SDS-PAGE.
Arabinose
;
Busan*
;
Cellobiose
;
Electrophoresis, Polyacrylamide Gel
;
Lactose
;
Membrane Proteins
;
Vibrio parahaemolyticus*
;
Vibrio vulnificus*
;
Vibrio*
4.Identification of Vibrio vulnificus in Pusan and Southern Sea of Korea in 1996 using API 20E Kit.
Jin Woo JU ; Cho Rok JUNG ; Kyung Sook KIM ; Soo Jung PARK ; Sun Ok YOON
Journal of the Korean Society for Microbiology 1998;33(2):187-194
The halophilic bacterium, Vibrio vulnificus, causes acute fulminating wound infections and septicemia in human. Especially the septicemia shows high mortality above 50%. In Korea, septicemia by V. vulnificus was reported at westem and southern coast in every year. Here, we try to isolate this V. vulnipcus at Kyoung-nam area and coast of Pusan during 1996. Purposed sites were Dadaepo, Songjung, Chungsapo and Mipo of Pusan and Kijang, Ilkuang, Juksoung, Dongam, Waljun and Chilam of southern sea. Total 40 strains of V. vulnipcus were isolated from sea samples. Biochemical characteristics of isolated V. vulnificus were almost same with reference strain V. vulnificus ATCC 27562 on Farmer's tests and on API 20E kit test. V. vulnificus isolates in 1996, fermented cellobiose and salicin but arabinose. and had resistance to 7% sodium chloride.
Arabinose
;
Busan*
;
Cellobiose
;
Humans
;
Korea*
;
Mortality
;
Sepsis
;
Sodium Chloride
;
Vibrio vulnificus*
;
Vibrio*
;
Wound Infection
5.Biochemical Characterization of an Extracellular beta-Glucosidase from the Fungus, Penicillium italicum, Isolated from Rotten Citrus Peel.
Ah Reum PARK ; Joo Hee HONG ; Jae Jin KIM ; Jeong Jun YOON
Mycobiology 2012;40(3):173-180
A beta-glucosidase from Penicillium italicum was purified with a specific activity of 61.8 U/mg, using a chromatography system. The native form of the enzyme was an 88.5-kDa tetramer with a molecular mass of 354 kDa. Optimum activity was observed at pH 4.5 and 60degrees C, and the half-lives were 1,737, 330, 34, and 1 hr at 50, 55, 60, and 65degrees C, respectively. Its activity was inhibited by 47% by 5 mM Ni2+. The enzyme exhibited hydrolytic activity for p-nitrophenyl-beta-D-glucopyranoside (pNP-Glu), p-nitrophenyl-beta-D-cellobioside, p-nitrophenyl-beta-D-xyloside, and cellobiose, however, no activity was observed for p-nitrophenyl-beta-D-lactopyranoside, p-nitrophenyl-beta-D-galactopyranoside, carboxymetyl cellulose, xylan, and cellulose, indicating that the enzyme was a beta-glucosidase. The kcat/Km (s-1 mM-1) values for pNP-Glu and cellobiose were 15,770.4 mM and 6,361.4 mM, respectively. These values were the highest reported for beta-glucosidases. Non-competitive inhibition of the enzyme by both glucose (Ki = 8.9 mM) and glucono-delta-lactone (Ki = 11.3 mM) was observed when pNP-Glu was used as the substrate. This is the first report of non-competitive inhibition of beta-glucosidase by glucose and glucono-delta-lactone.
beta-Glucosidase
;
Cellobiose
;
Cellulases
;
Cellulose
;
Chromatography
;
Citrus
;
Fungi
;
Glucose
;
Glucosides
;
Hydrogen-Ion Concentration
;
Penicillium
6.Mariannaea samuelsii Isolated from a Bark Beetle-Infested Elm Tree in Korea.
Longqing TANG ; Min Woo HYUN ; Yeo Hong YUN ; Dong Yeon SUH ; Seong Hwan KIM ; Gi Ho SUNG ; Hyung Kyoon CHOI
Mycobiology 2012;40(2):94-99
During an investigation of fungi from an elm tree infested with bark beetles in Korea, one isolate, DUCC401, was isolated from elm wood. Based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer and 28S rDNA (large subunit) sequences, the isolate, DUCC401, was identified as Mariannaea samuelsii. Mycelia of the fungus grew faster on malt extract agar than on potato dextrose agar and oatmeal agar media. Temperature and pH for optimal growth of fungal mycelia were 25degrees C and pH 7.0, respectively. The fungus demonstrated the capacity to degrade cellobiose, starch, and xylan. This is the first report on isolation of Mariannaea samuelsii in Korea.
Agar
;
Beetles
;
Cellobiose
;
DNA, Ribosomal
;
Fungi
;
Glucose
;
Hydrogen-Ion Concentration
;
Korea
;
Solanum tuberosum
;
Starch
;
Ulmus
;
Wood
7.Production of Polysaccharide by the Edible Mushroom, Grifola frondosa.
Mycobiology 2003;31(4):205-208
The production of polysaccharide according to various developmental stages (mycelium growth, primordium appearance, and fruiting-body formation) in the edible mushroom Grifola frondosa was studied. The cap of the mature mushroom showed the highest amount of polysacchride. Mycelial growth and polysaccharide synthesis were optimal at pH 5 and 20degrees C. Polysaccharide synthesis was maximal after 12 days of cultivation, whereas maximum mycelial growth was shown after 18 days. Mannose, cellobiose and starch increased the level of polysaccharide as well as growth in submerged culture. Glucose and sucrose appeared to be good substrates for fruiting of Grifola frondosa.
Agaricales*
;
Cellobiose
;
Fruit
;
Glucose
;
Grifola*
;
Hydrogen-Ion Concentration
;
Mannose
;
Starch
;
Sucrose
8.Enhancement of beta-Glucosidase Activity from a Brown Rot Fungus Fomitopsis pinicola KCTC 6208 by Medium Optimization.
Ah Reum PARK ; Jeong Hoon PARK ; Hye Jin AHN ; Ji Yeon JANG ; Byung Jo YU ; Byung Hwan UM ; Jeong Jun YOON
Mycobiology 2015;43(1):57-62
beta-Glucosidase, which hydrolyzes cellobiose into two glucoses, plays an important role in the process of saccharification of the lignocellulosic biomass. In this study, we optimized the activity of beta-glucosidase of brown-rot fungus Fomitopsis pinicola KCTC 6208 using the response surface methodology (RSM) with various concentrations of glucose, yeast extract and ascorbic acid, which are the most significant nutrients for activity of beta-glucosidase. The highest activity of beta-glucosidase was achieved 3.02% of glucose, 4.35% of yeast extract, and 7.41% ascorbic acid where ascorbic acid was most effective. The maximum activity of beta-glucosidase predicted by the RSM was 15.34 U/mg, which was similar to the experimental value 14.90 U/mg at the 16th day of incubation. This optimized activity of beta-glucosidase was 23.6 times higher than the preliminary activity value, 0.63 U/mg, and was also much higher than previous values reported in other fungi strains. Therefore, a simplified medium supplemented with a cheap vitamin source, such as ascorbic acid, could be a cost effective mean of increasing beta-glucosidase activity.
Ascorbic Acid
;
beta-Glucosidase*
;
Biomass
;
Cellobiose
;
Coriolaceae*
;
Fungi*
;
Glucose
;
Vitamins
;
Yeasts
9.Characterization of Fusarium oxysporum Isolated from Paprika in Korea.
Sang Do CHA ; Young Jae JEON ; Geum Ran AHN ; Jae In HAN ; Kap Hoon HAN ; Seong Hwan KIM
Mycobiology 2007;35(2):91-96
In the present study we first report in Korea the identification and characterization of Fusarium oxysporum isolated from rotten stems and roots of paprika (Capsicum annuum var. grossum) at Masan, Kyungsangnamdo in 2006. The fungal species produced white aerial mycelia accompanying with dark violet pigment on PDA. The optimal temperature and pH for the growth of the species was 25degrees C and pH 7, respectively. Microscopic observation of one of isolates of the species shows that its conidiophores are unbranched and monophialides, its microconidia have oval-ellipsoidal shape with no septate and are of 3.0~11 x 1.5~3.5 microm sizes, its macroconidia are of 15~20 x 2.0~3.5 microm sizes and have slightly curved or slender shape with 2~3 septate. The results of molecular analysis show that the ITS rDNA of F. oxysporum from paprika shares 100% sequence identity with that of known F. oxysporum isolates. The identified species proved it's pathogenicity by causing rotting symptom when it was inoculated on paprika fruits. The growth of F. oxysporum from paprika was suppressed on PDA by agrochemicals such as benomyl, tebuconazole and azoxystrobin. The identified species has the ability of producing extracelluar enzymes that degrade cellobiose and pectin.
Agrochemicals
;
Benomyl
;
Capsicum*
;
Cellobiose
;
DNA, Ribosomal
;
Fruit
;
Fusarium*
;
Gyeongsangnam-do
;
Hydrogen-Ion Concentration
;
Korea*
;
Viola
;
Virulence
10.Studies on immobilized cellobiase.
Chinese Journal of Biotechnology 2003;19(2):236-239
Cellulosic material is the most abundant renewable carbon source in the world. Cellulose may be hydrolyzed using cellulase to produce glucose, which can be used for production of ethanol, organic acids, and other chemicals. Cellulase is a complex enzyme containing endoglucanase (EC 3.2.1.4), exoglucanase (EC 3.2.1.91) and cellobiase (EC 3.2.1.21). The hydrolysis of natural cellulose to glucose depends on the synergism of these three components. The mostly used cellulase produced by Trichoderma reesei has high activity of endoglucanase and exoglucanase, but the activity of cellobiase is relatively low. Therefore, improving the activity of cellobiase in cellulase reaction system is the key to enhance the sacchrification yield of cellulosic resources. Aspergillus niger LORRE 012 was a high productivity strain for cellobiase production. It was found that the spores of this strain were rich in cellobiase. In this work, the cellobiase was immobilized efficiently by simply entrapping the spores into calcium alginate gels instead of immobilizing the pure cellobiase proteins. The immobilized cellobiase was quite stable, and its half-life was 38 days under pH 4.8, 50 degrees C. The thermal stability of the immobilized cellobiase was improved, and it was stable below 70 degrees C. The suitable pH range of the immobilized cellobiase was pH 3.0 - 5.0, with the optimal pH value 4.8. The Km and Vmax value of the immobilized cellobiase were 6.01 mmol/L and 7.06 mmol/min x L, respectively. In repeated batch hydrolysis processes, 50 mL of substrate (10 g/L cellobiose) and 10 mL of immobilized beads containing cellobiase were added into a 150 ml flask. After reacting at pH 4.8, 50 degrees C for several hours, the hydrolysate was harvested for assay, and the immobilized beads were used for the next batch hydrolysis with the fresh substrate. This process was repeated, and the yield of enzymatic hydrolysis kept higher than 97% during 10 batches. The continuous hydrolysis process was carried out in a column reactor (inside diameter 2.8 cm, inside height 40 cm) packed with the immobilized beads. Using 10 g/L cellobiose as substrate, the hydrolysis yield reached 98% under 0.4 h (-1) dilution rate and pH 4.8, 50 degrees C. After corncob was treated by 1% dilute acid, the cellulosic residue (100 g/L) was used as substrate, and hydrolyzed by the cellulase (15 IFPU/g substrate) from Trichoderma reesei, at pH 4.8, 50 degrees C for 48 h. The concentration of reducing sugar in the hydrolysate was only 48.50 g/L (hydrolysis yield 69.5%). When the hydrolysate was further treated by the immobilized cellobiase, the cellobiose was hydrolyzed into glucose, and the feedback inhibition caused by the cellobiose accumulation disappeared sharply. By the synergism of immobilized cellobiase and the cellulase from T. reesei left in the hydrolysate, other oligosaccharides were mostly converted to monosaccharides. At 48 h, the reducing sugar concentration was increased to 58.78 g/L, the hydrolysis yield of the corncob residue was improved to 84.2%, and the ratio of the glucose in the total reducing sugar was increased from 53.6% to 89.5%. The reducing sugars converted from corncob could be used further in the fermentation of valuable industrial products. This research results were meaningful in the conversion and utilization of renewable biomass.
Aspergillus niger
;
enzymology
;
Biotechnology
;
Cellobiose
;
metabolism
;
Enzyme Stability
;
Hydrogen-Ion Concentration
;
Kinetics
;
Temperature
;
beta-Glucosidase
;
chemistry
;
metabolism