• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.137-141
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• 2013

In this study, nucleotide sequence structures of intergenic transcribed spacer (ITS) 1, complete 5.8S ribosomal RNA gene and ITS 2 region were analyzed to identify three Peruvian entomopathogenic fungal isolates. The isolates had highly conserved sequence region in 5.8S rRNA gene and unique sequences in ITS 1 and 2 region among them. 5.8S rRNA gene regions were highly conserved and showed high homoloies among tested isolates. In contrast, ITS region showed species-specific sequence region, resulting in inter-genus differencies. Scanning electron microscopic images of these isolates supported the result of ITS-based identification. From these result, Peruvian entomopathogenic fungal isolate J270, J278, were identified as Beauveria bassiana and J271 was identified as Lecanicillium attenuatum.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.72-78
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• 2016

BACKGROUND: Entomopathogenic fungi have been studied to develop for biological control agents as an alternative to chemical control agents in insect pest management. This investigated to determine the optimal culture conditions in ceramic balls for maximal sporulation of entomopathogenic fungi Beauveria bassiana M130 by use rice bran extract.METHODS AND RESULTS: METHODS AND RESULTS: A culture of entomopathogenic fungi for 12day on rice bran extract(1:8, w/v) incubated in ceramic matrix at 28℃. Natural zeolite ceramic ball was high production of 4.2×108 conidial/mL. The culture condition optimized initial pH, temperature, rice bran extract concentration, adhesives substance and concentration of NaCl, respectively. The high production of spore optimal conditions were temperature 28℃, initial pH 3, rice bran extract 3 mL, starch 33 g, 5 % NaCl and sopre suspension 7 mL, respectively.CONCLUSION: This study was carried out for the mass production of entomopathogenic fungi conidia recover rate 65% in matrix of natural zeolite ceramic ball, and to develop ingredient-used formulation of Beauveria bassiana M130 conidia for biological control agents.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.27-28
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• 2014

Beauveria bassiana (Cordycipitaceae, Hypocreales, Ascomycota) is an anamorphic fungus having a potential to be used as a biological control agent because it parasitizes a wide range of arthropod hosts including termites, aphids, beetles and many other insects. A number of bioactive secondary metabolites (SMs) have been isolated from B. bassiana and functionally verified. Among them, beauvericin and bassianolide are cyclic depsipeptides with antibiotic and insecticidal effects belonging to the enniatin family. Non-ribosomal peptide synthetases (NRPSs) play a crucial role in the synthesis of these secondary metabolites. NRPSs are modularly organized multienzyme complexes in which each module is responsible for the elongation of proteinogenic and non-protein amino acids, as well as carboxyl and hydroxyacids. A minimum of three domains are necessary for one NRPS elongation module: an adenylation (A) domain for substrate recognition and activation; a tholation (T) domain that tethers the growing peptide chain and the incoming aminoacyl unit; and a condensation (C) domain to catalyze peptide bond formation. Some of the optional domains include epimerization (E), heterocyclization (Cy) and oxidation (Ox) domains, which may modify the enzyme-bound precursors or intermediates. In the present study, we analyzed genomes of B. bassiana and its allied species in Hypocreales to verify the distribution of NRPS-encoding genes involving biosynthesis of beauvericin and bassianolide, and to unveil the evolutionary processes of the gene clusters. Initially, we retrieved completely or partially assembled genomic sequences of fungal species belonging to Hypocreales from public databases. SM biosynthesizing genes were predicted from the selected genomes using antiSMASH program. Adenylation (A) domains were extracted from the predicted NRPS, NRPS-like and NRPS-PKS hybrid genes, and used them to construct a phylogenetic tree. Based on the preliminary results of SM biosynthetic gene prediction in B. bassiana, we analyzed the conserved gene orders of beauvericin and bassianolide biosynthetic gene clusters among the hypocrealean fungi. Reciprocal best blast hit (RBH) approach was performed to identify the regions orthologous to the biosynthetic gene cluster in the selected fungal genomes. A clear recombination pattern was recognized in the inferred A-domain tree in which A-domains in the 1st and 2nd modules of beauvericin and bassianolide synthetases were grouped in CYCLO and EAS clades, respectively, suggesting that two modules of each synthetase have evolved independently. In addition, inferred topologies were congruent with the species phylogeny of Cordycipitaceae, indicating that the gene fusion event have occurred before the species divergence. Beauvericin and bassianolide synthetases turned out to possess identical domain organization as C-A-T-C-A-NM-T-T-C. We also predicted precursors of beauvericin and bassianolide synthetases based on the extracted signature residues in A-domain core motifs. The result showed that the A-domains in the 1st module of both synthetases select D-2-hydroxyisovalerate (D-Hiv), while A-domains in the 2nd modules specifically activate L-phenylalanine (Phe) in beauvericin synthetase and leucine (Leu) in bassianolide synthetase. antiSMASH ver. 2.0 predicted 15 genes in the beauvericin biosynthetic gene cluster of the B. bassiana genome dispersed across a total length of approximately 50kb. The beauvericin biosynthetic gene cluster contains beauvericin synthetase as well as kivr gene encoding NADPH-dependent ketoisovalerate reductase which is necessary to convert 2-ketoisovalarate to D-Hiv and a gene encoding a putative Gal4-like transcriptional regulator. Our syntenic comparison showed that species in Cordycipitaceae have almost conserved beauvericin biosynthetic gene cluster although the gene order and direction were sometimes variable. It is intriguing that there is no region orthologous to beauvericin synthetase gene in Cordyceps militaris genome. It is likely that beauvericin synthetase was present in common ancestor of Cordycipitaceae but selective gene loss has occurred in several species including C. militaris. Putative bassianolide biosynthetic gene cluster consisted of 16 genes including bassianolide synthetase, cytochrome P450 monooxygenase, and putative Gal4-like transcriptional regulator genes. Our synteny analysis found that only B. bassiana possessed a bassianolide synthetase gene among the studied fungi. This result is consistent with the groupings in A-domain tree in which bassianolide synthetase gene found in B. bassiana was not grouped with NRPS genes predicted in other species. We hypothesized that bassianolide biosynthesizing cluster genes in B. bassiana are possibly acquired by horizontal gene transfer (HGT) from distantly related fungi. The present study showed that B. bassiana is the only species capable of producing both beauvericin and bassianolide. This property led to B. bassiana infect multiple hosts and to be a potential biological control agent against agricultural pests.

• The Korean Journal of Food And Nutrition
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• v.16 no.2
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• pp.158-164
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• 2003

This study was conducted to investigate the properties of noodle which was made of composite flour blended with the powder of synnemata of Beauveria bassiana. The characteristics of cooked-noodle including color, cooking properties, mechanical texture properties were measured, and sensory evaluation was performed. The L-value of dry and wet-noodle which made of composite flour was similar to that of 100% wheat flour, but a and b-value were higher than those of 100% wheat flour. There were no differences in the weight, volume and water absorption of the cooked-noodle made of composite flour and that of 100% wheat flour, but the turbidity of the cooked-noodle made of composite flour was higher than that of 100% wheat flour. The breaking force of dry-noodle which was made of composite flour was same as that of 100% wheat flour. Hardness and Gumminess of the cooked-noodle which was made of composite flour blended with synnemata powder at level of 1∼5% were same as those of 100% wheat flour. Springiness, chewiness, cohesiveness and adhesiveness of the cooked-noodle which was made of composite flour blended with synnemata powder at level of 1% were similar to those 100% wheat flour. The results of sensory evaluation showed that the cooked-noodles containing 1% and 3% synnemata powder were acceptable as much as those of 100% wheat flour in terms of color, taste, flavor, texture and overall acceptance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.997-1001
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• 2003

Addition of synnemata of Beauveria bassiana on the baking qualities of bread was studied. There were no differences in the loaf volume of bread made of composite flour blended with the synnemata powder at level of 1%, 3% from that of control, but that of 5% was lower than the control. The addition of synnemata powder caused a decrease in the lightness of bread crumb and an increase in the redness and yellowness. The hardness of bread made of composite flour blended with synnemata powder at level of 1% and 3% was similar to that of control, while 5% addition was higher than the control. There were no differences in the springiness, gumminess and chewiness of bread made with synnemata powder at level of 1%, 3% from those of control. In sensory evaluation, the addition of the synnemata powder at level of 1% and 3% did not affect appearance, flavor, taste, texture and overall acceptability, while 5% addition significantly decreased those values.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.171-179
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• 2000

- Turfgrass insect pests and natura.l enemies for biological control were investigated to develop pest management effectively in golf courses at several golf clubs. Twenty eight insect pest species of 10 families in 6 orders were collected from golf courses. The zoysiagrass mite, Eriophyes zoysiae and root-knot nematode, Meloidogyne incognita were also collected from zoysiagrass. White grubs of several scarab beetles and cutworms (Agrotis spp.) damaged seriously at most surveyed golf clubs. In addition, bluegrass webworm (Crambus sp.), Japanese lawngrass cutworm (Spodoptera depravata), scale insects, Tipula sp., and ants (Camponitus japonicus, Formica japonica, and Lasins japonicus) damaged turfgrasses directly or indirectly in golf courses. The entomopathogenic nematodes, Heterorhabditis spp., Steinernema glaseri, and S. longicaudum, entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae, and milky disease, Paenibacil/us popil/iae were isolated from white grubs or turfgrass soil as microbial control agents. Besides, dipteran predators, Cophinopoda chinensis, Philonicus albiceps, and Promachus yesonicus and hymenopteran parasitoid, Tiphia sp. were also collected. The P. yesonicus was the most active in golf courses. The root-knot nematode, M. incognita was found from Zoysia japonica, Z. matrella. and Cynodon dactylon.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.229-234
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• 2004

Six entomopathogenic fungus isolates, Beauveria bassiana J57A, Nomuraea rileyi J125A, Paecilomyces farinosus J3A, Paecilomyces fumosoroseus J50A, Metarhizium anisopliae J88, Aspergilius sp. J64A, causing muscardine disease and aspergillosis in the silkworm, Bombyx mori were investigated for their cultural and morphological characteristics (on PDA culture media within 14 days at $24^{\circ}C$). The results showed that they differ each other from the features of cultural characteristics (colony elevation, colony color, colony growth rate) or morphological characteristics (conidiogenous cell structure, phialides, conidia size and shape). Among cultural characteristics, colony color is the easiest recognizable character between isolates. The morphological characteristics of each fungal isolate correspond to the descriptions of current system of classification.

• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1494-1500
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• 2012

Fermentation with filamentous fungi in a bioreactor is a complex dynamic process that is affected by flow conditions and the evolution of the rheological properties of the medium. These properties are mainly affected by the biomass concentration and the morphology of the fungus. In this work, the rheological properties of a fermentation with the fungus Beauveria bassiana under different hydrodynamic conditions were studied and the rheological behavior of this broth was simulated through a mixture of carboxymethyl cellulose sodium and cellulose fibers (CMCNa-SF). The bioreactor was a 10 L CSTR tank operated at different stir velocities. Rheological results were similar at 100 and 300 rpm for both systems. However, there was a significant increase in the viscosity accompanied by a change in the consistence index, calculated according to the power law model, for both systems at 800 rpm. The systems exhibited shear-thinning behavior at all stir velocities, which was determined with the power law model. The mixing time was observed to increase as the cellulose content in the system increased and, consequently, the efficiency of mixing diminished. These results are thought to be due to the rheological and morphological similarities of the two fungal systems. These results will help in the optimization of scale-up production of these fungi.

• Journal of Sericultural and Entomological Science
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• v.44 no.1
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• pp.32-36
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• 2002

Occurrence and characteristics of infectious fungi and physiologically abnormal Paecilomyces tenuipes were examined. These unfavorable fungi are recently known to cause yield loss, decreased quality of products in artificial cultivation farms of P. tenuipes. Total 529 fungal isolates were collected from 22 farms of 7 provinces. These isolates were composed of physiologically abnormal P. tenuipes strains and other infectious fungal strains, which constituted 23.2% and 50.9%, respectively. Physiologically abnormal P. tenuipes strains showed irregular synemata, and absence of local color. They were divided into 4 types or C-l, C-2, C-3 and C-4. Other infectious fungal strains were identified to 5 species, Beauveria bassiana, Fusarium sp., P fumosoroseus, Tricothecium roseum, Aspergillus parasiticus, which were 22.1, 13.8, 7.6, 4.0 and 3.4%, respectively. All of them were hyphomycetous fungi, did not produce synemata, and revealed faster growth rate than that of P. tenuipes.

• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.25-30
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• 2003

This study was carried out to investigate active constituents of Bombysis corpus on the neurite outgrowth from PC 12 cells led to isolate three new and a known sphingolipids from the n-hexane soluble portion and five amines from the butanol soluble portion of its methanol extract. On the basis of spectroscopic data, their structures have been elucidated as (4E,6E,2S,3R)-2-N-eicosanoyl-4,6-tetradecasphingadienine, (4E,2S,3R)-2-N-eicosanoyl-4-tetradecasphingenine,(4E,6E,2S,3R)-2-N-docosanoyl-4,6-tetradecasphingadienine,(4E,6E,2S,3R)-2-N-docosanoyl-4,6-tetradecasphingadienine,(4E,2S,3R)-2-N-octadecanoyl-4-tetradecasphingenine, 1,7-dimethyl-xanthine, uracil, urea, betaine and tyrosine, respectively. The neurite outgrowth activities of these compounds were examined in PC12 cells by measuring the length of neurites. These compounds promoted neurite outgrowth in PC12 cells significantly.