• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.82-88
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• 1986

Five antifungal substances were isolated from the long-term storaged extract of common purslane, and identified as isobutyric, butyric, isovaleric, valerie and caproic acids belonging to short-chain fatty acids (C4­C6). Each of these fatty acids showed more or less antifungal potency against spore germination and mycelial growth of Alternaria alternata Japanese pear pathotype in vitro. Antifungal potency of each fatty acid against spore germination was greater than that against the mycelial growth. No one of these fatty acids completely inhibited the mycelial growth at concentration lower than 200 ppm, while 50 ppm of caproic acid and 200 ppm of valerie acid completely inhibited the spore germination. The results of bioassay also suggested that chain-length of the fatty acids might be related with the antifungal potency, since fatty acids with longer chain showed higher antifungal potency.

• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.749-759
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• 2009

A survey of Bacillus thuringiensis (Berliner) strains isolated from Spanish citrus orchards has been performed, and the strains were tested for insecticidal activity against the Mediterranean fruit fly Ceratitis capitata (Wiedemann), a key citrus pest in Spain. From a total of 150 environmental samples, 376 isolates were selected, recording a total B. thuringiensis index of 0.52. The collection was characterized by means of phase-contrast microscopy, SDS-PAGE, and PCR analysis with primer pairs detecting toxin genes cry1, cry2, cry3, cry4, cry5, cry7, cry8, cry9, cry10, cry11, cry12, cry14, cry17, cry19, cry21, cry27, cry39, cry44, cyt1, and cyt2. Diverse crystal inclusion morphologies were identified: bipyramidal (45%), round (40%), adhered to the spore (7%), small (5%), and irregular (3%). SDS-PAGE of spore-crystal preparations revealed 39 different electrophoresis patterns. All primer pairs used in PCR tests gave positive amplifications in strains of our collection, except for primers for detection of cry3, cry19, cry39, or cry44 genes. Strains containing cry1, cry2, cry4, and cry27 genes were the most abundant (48.7%, 46%, 11.2%, and 8.2% of the strains, respectively). Ten different genetic profiles were found, although a total of 109 strains did not amplify with the set of primers used. Screening for toxicity against C. capitata adults was performed using both spore-crystal and soluble fractions. Mortality levels were less than 30%. We have developed a large and diverse B. thuringiensis strain collection with huge potential to control several agricultural pests; however, further research is needed to find out Bt strains active against C. capitata.

• Journal of Microbiology and Biotechnology
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• v.20 no.1
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• pp.208-216
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• 2010

Fusarium verticillioides is an important pathogen of maize, being responsible for ear rots, stalk rots, and seedling blight worldwide. During the past decade, F. verticillioides has caused several severe epidemics of maize seedling blight in many areas of China, which lead to significant losses. In order to understand the molecular mechanisms regulating fungal development and pathogenicity in this pathogen, we isolated and characterized the gene fpk1 (GenBank Accession No. EF405959) encoding a homolog of the cAMP-dependent protein kinase catalytic subunit, which included a 1,854-bp DNA sequence from ATG to TAA, with a 1,680-bp coding region, and three introns (lengths: 66 bp, 54 bp, and 54 bp), and the predicated protein precursor had 559 aa. The mutant ${\Delta}fpk1$, which was disrupted of the fpkl gene, showed reduced vegetative growth, fewer and shorter aerial mycelia, strongly impaired conidiation, and reduced spore germination rate. After germinating, the fresh hypha was stubby and lacking of branch. When inoculated in susceptible maize varieties, the infection of the mutant ${\Delta}fpk1$ was delayed and the infection efficiency was reduced compared with that of the wild-type strain. AU this indicated that gene fpk1 participated in hyphal growth, conidiophore production, spore germination, and virulence in F. verticillioides.

• Applied Biological Chemistry
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• v.31 no.1
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• pp.38-45
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• 1988

Potential mutagenicity of ten heated edible mountain herbs were examined with spore recassay, Ames test and DNA breaking test. Samples of edible mountain herbs were prepared with water extraction at $100^{\circ}C$ for 20 minutes. With the rec-assay, no significant mutagengic activity could be obtained from all of the samples, but among the eight of metal ions added to sample solution, $Pb^{2+}$ to R. crispus heated juice, $Zn^{2+}$ to L. fischeri and S. bracycarpa heated juice increased mutagenic activity of the samples. With the Ames test and DNA breaking test, all of the samples did not show mutagenicity. However, breaking action was activated on heated L. fischeri, P. japonicus. A. triphylla and A. tataricus juices in the presence of 25mM $Cu^{2+}$. But heated A. elata, H. aurantiaca, A. triphylla, S. bracycarpa and A. scaber juices were inactivated in the presence of 25mM $Fe^{2+}$. Desmutagenic activities against benzo$({\alpha})$pyrene significantly increased as increasing concentration of the heated edible mountain herb juices.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.352-356
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• 1997

To induce the phytoalexins in plant cell culture systems, we surveyed the antimicrobial activity following the feeding of five naphthoquinones in cell cultures of petunia. Among naphthoquinones treated, 2,5,7-trihydroxy-3-(5'-hydroxyhexyl)-1,4-naphthoquinone (3-OH NQ ) was most efficiently absorbed into the cells within 48 hr. The crude extracts of cells treated with 3-OH NQ showed a strong inhibition activity on spore germination of Aspergillus candidus $(MIC:\;32\;{\mu}g/ml)$, whereas the untreated cells showed no activity. The two active compounds, 4,2',4',${\beta}$-tetrahydroxychalcone and 4',7-dihydroxyflavone, were isolated from petunia cells treated with 3-OH NQ. The major phytoalexin, 4,2',4',${\beta}$-tetrahydroxychalcone, inhibited strongly the spore germination of A. candidus $(MIC:\;16\;{\mu}g/ml)$.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.172-183
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• 1994

The productions of arbuscular mycorrhizal fungal(AMF) spores were observed by adding three different commercial fertilizers on AMF inhabiting soils. Various morphological features, vesicles, arbuscles, sporulations of spore, and flower-like-structures, were also found in the mycorrhizal roots during 80 days after transplanting. Spore prodcutions of the employed AMF were observed to be periodically increased with the intervals of 40 days. Sorghum, green onion, hot pepper, and wild legume plants were appeared to be a good plant for productions of AMF and as the host of AMF. The productions of AMF spores was inversely related to phosphate fertilizer, and also observed to be low in the plant pots added with whole balanced fertilizers.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.99-103
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• 1984

Hyphal growth by Fusarium moniliforme was best at -14 bars osmotic water potential. Hyphal growth was prevented at -94 bars. The production of microconidia was best at -14 bars osmotic potential and prevented at -84 bars regardless of Strain. In contrast, this fungus sporulated macroconidia best at -1.4 bars and progressively less with each increment drop in water potential below that of basal media. The rate of spore germination followed a similar pattern with all of the spores; uniformly maximal at about -1.4 bars and progressively slower as the water potential was lowered from -1.4 bars to -42 bars. Under the natural conditions, plants infected by F. moniliforme produce microconidia on the dead tissues instead of producing macroconidia. This phenomenon agrees well with the water potential experiment since the dead plant tissues have a lower water potential than the living plant.

• The Korean Journal of Mycology
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• v.20 no.3
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• pp.222-228
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• 1992

Pleurotus florida was transformed by complementation of auxotrophic mutant using chimeric plasmid containing Flammulina velutipes leu 2 gene and pBR 322 replicon. Mycelial morphology of transformants was grown and compared on mushroom complete and minimal medium. Transformants were mated with monokaryon and their genetic recombination was investigated for the morphology of fruitbody and spore analysis. $Leu^+$ transformant showed same mating type of $A_1B_1$ as to the untransformed mutant. The transformant and the untransformed mutant were mated with monokaryon of which mating type is $A_2B_1$, respectively. Although fruitbody of the untransformed mutant was not produced, $leu^+$ transformant produced fruitbody. Spore analysis showed that leucine requiring spores from fruitbody of $leu^+$ transformant were diminished when compared with those of untransformed mutant.

• BMB Reports
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• v.42 no.1
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• pp.47-52
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• 2009

Alanine racemase catalyzes the interconversion of L-alanine and D-alanine and plays a crucial role in spore germination and cell wall biosynthesis. In this study, alanine racemase produced by Bacillus anthracis was expressed and purified as a monomer in Escherichia coli and the importance of lysine 41 in the cofactor binding octapeptide and tyrosine 270 in catalysis was evaluated. The native enzyme exhibited an apparent $K_m$ of 3 mM for L-alanine, and a $V_{max}$ of $295\;{\mu}moles/min/mg$, with the optimum activity occurring at $37^{\circ}C$ and a pH of 8-9. The activity observed in the absence of exogenous pyridoxal 5'-phosphate suggested that the cofactor is bound to the enzyme. Additionally, the UV-visible absorption spectra indicated that the activity was pH independece, of VV-visible absorption spectra suggests that the bound PLP exists as a protonated Schiff's base. Furthermore, the loss of activity observed in the apoenzyme suggested that bound PLP is required for catalysis. Finally, the enzyme followed non-competitive and mixed inhibition kinetics for hydroxylamine and propionate with a $K_i$of $160\;{\mu}M$ and 30 mM, respectively.

• Journal of Convergence for Information Technology
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• v.10 no.5
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• pp.232-238
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• 2020

This study evaluated the anti-aging activity with antioxidant, anti-inflammatory and moisture activity of Ganoderma lucidum spore oil(GLS). GLS increased DPPH radical scavenging activity in a dose-dependent manners. Anti-inflammatory assay measured the inhibitory effect of GLS on NO, TNF-α and IL-6 production in LPS-stimulated RAW264.7 cells. As a result GLS inhibited NO and pro-inflammatory cytokine, TNF-α, IL-6 production. Also using human fibroblast cell to the procollagen production analysis and COL1A1 mRNA expression level analysis for defining, and for AQP-3 mRNA expression level analysis, used human keratinocyte cell. GLS increased procollagen production and COL1A1, AQP-3 mRNA expression. Our results suggest that the GLS have potential anti-inflammatory and wrinkle improves, skin moisture effect.