• Journal of Microbiology and Biotechnology
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• v.20 no.9
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• pp.1348-1350
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• 2010

Conidia of Beauveria bassiana ARSEF-7060, produced in millet amended with plant oils such as sunflower, corn, or cotton seed oil, were exposed to $45^{\circ}C$ of wet heat for 90 min. Conidia from millet+corn oil medium had the highest thermotolerance [$LT_{50}$ (median survival time): 45.7 min]. The mycotized millet grains were coated with each of the same plant oils as a granular formulation and subjected to $50^{\circ}C$ of dry heat for 8 h. Corn oil coating ($LT_{50}$: 8.68 h) was superior to sunflower and cotton seed oil coatings, suggesting the feasibility of using corn oil to increase conidial thermotolerance.

• Journal of Forest and Environmental Science
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• v.30 no.2
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• pp.243-252
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• 2014

Forest tree species usually takes for long periods to be harvested and cultivated but spearmints are a good model system for woody plant because of reducing and shortening cultivation time. Spearmints are good model plants (Mentha species) for research about terpenoids production and industrial essential oil manufacture. Isopentenyl pyrophosphate isomerase (Iso) and limonene synthase (Limo) are the key enzymes of terpenoid biosynthesis pathway. Transgenic and wild spearmints (Mentha spicata, MS) were cultured in vitro and assessed for the essential oil contents. The content of essential oil of transgenic spearmint also was enhanced slightly depending on the target terpenoid genes. In an attempt to increase productivity of terpenoids further, salt and fungal elicitation strategy was adopted on transgenic Mentha spicata. The salt (800 mM NaCl) as abiotic and two fungi (Botrytis cinerea and Glomerella cingulata) as biotic were used for elicitors. In the absence of salt stress four terpenoids were detected from the spearmint extracts, all of them being monoterpenes. On the other hand, the transgenic (MSIso) extracts contained eleven terpenoids (10 monoterpenes and 1 phenylpropene) while transgenic (MSLimo) extracts contained seven monoterpenes. After 3 days of fungal infection, the resistance indices further increased to 4.38, 3.89 and 2.04 for wild type, MSIso and MSLimo, respectively. The salt and fungal elicitators proved beneficial towards modifying both the terpenoids profile and improvement in the composition of essential oil. These results have important applications for the large-scale production of essential oils and forest biotechnology with respect to spearmint.

• Mycobiology
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• v.41 no.4
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• pp.221-224
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• 2013

Aphids are one of the most destructive pests in crop production such as pepper, cucumber, and eggplants. The importance of entomopathogenic fungi as alternative pest control agents is increasing. Conidia of entomopathogenic fungi are influenced by environmental conditions, such as temperature and relative humidity, and cause slow and fluctuating mortality. These factors have prevented wider application and use of biocontrol agents. For investigation of means of mitigation of such problems, we conducted bioassays with 47 fungal culture filtrates in order to evaluate the potential of secondary metabolites produced by entomopathogenic fungi for use in aphid control. Among 47 culture filtrates cultured potato dextrose broth, filtrate of Beauveria bassiana Bb08 showed the highest mortality (78%) against green peach aphid three days after treatments. Filtrate of Bb08 cultured in Adamek's medium showed higher toxicity as 100% to third instar nymphs of the aphid compared with seven other filtrates cultured in different broths amended with colloidal chitin or oil. The culture filtrates and fungal cultures from media amended with colloidal chitin or oil had lower control efficacies than filtrates without these additives in three different media. These results indicate that the fungal culture fluid or culture filtrate of B. bassiana Bb08 cultured in Adamek's medium has potential for development as a mycopesticide for aphid control.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.309-310
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• 2005

Bioconverted linolenic acid (bLNA) obtained from linolenic acid by Pseudomonas aeruginosa PR3, showed anti-fungal activity against plant pathogens such as B. cinerea, F. oxysporum, F. solani, P. capsici and C. capsici. The oil sample also showed anti-fungal activity with MIC values, ranging from >250 to >1,000 ${\mu}g/ml$. Varied concentrations of bLNA had a great potential effect on spore germination of different fungi.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.497-502
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• 2008

The essential oil from the cones of Pinus koraiensis was prepared after removing the seeds, and its chemical composition analyzed using gas chromatography-mass spectrometry (GC-MS). Hydrodistillation of the P. koraiensis cones yielded 1.07% (v/w) of essential oil, which was almost three times the amount of essential oil extracted from the needles of the same plant. Moreover, the antimicrobial activities of the oil against the growth of Gram-positive bacteria, Gram-negative bacteria, and fungi were evaluated using the agar disc diffusion method and broth microdilution method. Eighty-seven components, comprising about 96.8% of the total oil, were identified. The most abundant oil components were limonene (27.90%), ${\alpha}$-pinene (23.89%), ${\beta}$-pinene (12.02%), 3-carene(4.95%), ${\beta}$-myrcene (4.53%), isolongifolene (3.35%), (-)-bornyl acetate (2.02%), caryophyllene (1.71%), and camphene (1.54%). The essential oil was confirmed to have significant antimicrobial activities, especially against pathogenic fungal strains such as Candida glabrata YFCC 062 and Cryptococcus neoformans B 42419. Therefore, the present results indicate that the essential oil from the cones of Pinus koraiensis can be used in various ways as a nontoxic and environmentally friendly disinfectant.

• 보존과학연구
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• s.33
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• pp.5-17
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• 2012

An Ola leaf manuscript, which consists of words carved on an Ola leaf and is filled up with a mixture of herbal oils made from Vateria acuminata Hyne and charcoal, is one of the native writing media in Sri Lanka. According to historical records, Ola leaf manuscripts had been used from the 1st to the 18th century A.D. From the recent findings that Ola leaf manuscripts have been preserved well for the past 400 years and are in good state of preservation, it is supposed that herbal oils preserve Ola leaves against environmental and biological factors such as fungi and insects. To evaluate the anti-biological susceptibility of the herbal oils, the molds isolated from wooden printing blocks in Janggyeong Panjeon of Haeinsa Temple in South Korea and bacteria and fungi isolated from Ola leaves were cultured. After spreading the microorganisms suspension on an agar plate, a disk paper containing a certain volume of herbal oil was placed on the agar plate. It was found in the experiment that herbal oil exhibits a clear zone, which is optically clear and inhibits the growth of microorganisms, against some molds and bacteria. The study results indicate that the herbal oil from the plant Vateria acuminata Hyne has the anti-bacterial and anti-fungal properties.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.815-820
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• 2008

Two culture-independent methods, namely ribosomal DNA libraries and denaturing gradient gel electrophoresis (DGGE), were adopted to examine the microbial community of a Malaysian light crude oil. In this study, both 16S and 18S rDNAs were PCR-amplified from bulk DNA of crude oil samples, cloned, and sequenced. Analyses of restriction fragment length polymorphism (RFLP) and phylogenetics clustered the 16S and 18S rDNA sequences into seven and six groups, respectively. The ribosomal DNA sequences obtained showed sequence similarity between 90 to 100% to those available in the GenBank database. The closest relatives documented for the 16S rDNAs include member species of Thermoincola and Rhodopseudomonas, whereas the closest fungal relatives include Acremonium, Ceriporiopsis, Xeromyces, Lecythophora, and Candida. Others were affiliated to uncultured bacteria and uncultured ascomycete. The 16S rDNA library demonstrated predomination by a single uncultured bacterial type by >80% relative abundance. The predomination was confirmed by DGGE analysis.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1617-1622
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• 2006

Long-term storage of feeds or feedstuffs in high temperature and humid conditions can be difficult because of microbial contamination. Essential oil isolated from industrial waste citrus peel could be used as a preservative because it is likely to have anti-bacterial and anti-fungal activity. Our objective was to determine whether different levels (0.028, 0.056 and 0.112 g/kg) of citrus essential oil (CEO) would provide anti-microbial activity and enhance preservation of animal feed without influencing rumen fermentation. At 0.112 g/kg, CEO inhibited growth of Escherichia coli (ATCC 25922) and Salmonela enteritidis (IFO 3313). Growth of E. coli recovered after 24 h of incubation, but S. enteritidis continued to be inhibited for 72 h. Preservation of antibiotic-free diets for swine was assessed by observing anti-aflatoxin activity. Aflatoxin was detected in control feed samples on days 16 (8 ppb) and 21 (8 ppb) and in anti-fungal agent (AA) treated samples on days 16 (2 ppb) and 21 (4 ppb). However, aflatoxin was not detected in feed samples treated with CEO. Treatment with CEO and AA did not influence ruminal pH, dry matter digestibility (DMD) or organic matter digestibility (OMD) over 48 h of incubation in rumen fluid. Acetate and propionate were slightly higher with CEO treatment (p<0.05), but total concentration of volatile fatty acid (VFA) was not significantly affected by treatment. Ammonia-N concentration was slightly higher for the control treatment (p<0.05). This study showed that treating feed with CEO enhances preservation of animal feed without influencing in vitro rumen fermentation.

• Journal of Microbiology and Biotechnology
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• v.25 no.4
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• pp.459-463
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• 2015

This study evaluated the microbial conversion of coconut oil waste, a major agro-residue in tropical countries, into single cell oil (SCO) feedstock for biodiesel production. Copra cake was used as a low-cost renewable substrate without any prior chemical or enzymatic pretreatment for submerged growth of an oleaginous tropical mangrove fungus, Aspergillus terreus IBB M1. The SCO extracted from fermented biomass was converted into fatty acid methyl esters (FAMEs) by transesterification and evaluated on the basis of fatty acid profiles and key fuel properties for biodiesel. The fungus produced a biomass (8.2 g/l) yielding 257 mg/g copra cake SCO with ~98% FAMEs. The FAMEs were mainly composed of saturated methyl esters (61.2%) of medium-chain fatty acids (C12-C18) with methyl oleate (C18:1; 16.57%) and methyl linoleate (C18:2; 19.97%) making up the unsaturated content. A higher content of both saturated FAMEs and methyl oleate along with the absence of polyunsaturated FAMEs with ≥4 double bonds is expected to impart good fuel quality. This was evident from the predicted and experimentally determined key fuel properties of FAMEs (density, kinematic viscosity, iodine value, acid number, cetane number), which were in accordance with the international (ASTM D6751, EN 14214) and national (IS 15607) biodiesel standards, suggesting their suitability as a biodiesel fuel. The low cost, renewable nature, and easy availability of copra cake, its conversion into SCO without any thermochemical pretreatment, and pelleted fungal growth facilitating easier downstream processing by simple filtration make this process cost effective and environmentally favorable.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.464-465
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• 2006