• Mycobiology
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• v.39 no.3
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• pp.158-163
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• 2011

This study was conducted to confirm the possible use of female Yangwonjam as a host for synnemata production of Isaria tenuipes in eight local areas in Korea. Silkworm pupation rate, infection rate and synnemata characteristics of I. tenuipes were examined. Normal silkworms had a higher pupation rate than silkworms inoculated with I. tenuipes. The pupae survival percentage of normal silkworm in cocoons was 92.5~97.6%, whereas it ranged from 91.1~95.6% in silkworms sprayed with I. tenuipes. Female Yangwonjam showed the highest survival percentage at 97.6% among the silkworm varieties tested. I. tenuipes infection rate of larvae of 5th instar newly-exuviated silkworms was 89.2~90.7% in the spring rearing season and 98.2~99.3% in the autumn rearing season. Synnemata production of I. tenuipes was excellent in female Yangwonjam with an incidence rate of 98.0% followed by male Yangwonjam (94.1%) and Baegokjam (93.3%) in the spring rearing season. Synnemata living weight ranged from 1.44~0.94 g in the spring rearing season. The female Yangwonjam had the heaviest synnemata weight (1.44 g) in the spring rearing season. The synnemata of I. tenuipes produced on pupae were white or milky-white in color, and were similar in shape and color to wild synnemata collected in Korea.

• Mycobiology
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• v.42 no.4
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• pp.346-352
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• 2014

Recently, the Q biotype of tobacco whitefly has been recognized as the most hazardous strain of Bemisia tabaci worldwide, because of its increased resistance to some insecticide groups. As an alternative control agent, we selected an Isaria javanica isolate as a candidate for the development of a mycopesticide against the Q biotype of sweet potato whitefly. To select optimal mass production media for solid-state fermentation, we compared the production yield and virulence of conidia between 2 substrates (barley and brown rice), and we also compared the effects of various additives on conidia production and virulence. Barley was a better substrate for conidia production, producing $3.43{\times}10^{10}$ conidia/g, compared with $3.05{\times}10^{10}$ conidia/g for brown rice. The addition of 2% $CaCO_3+2%$ $CaSO_4$ to barley significantly increased conidia production. Addition of yeast extract, casein, or gluten also improved conidia production on barley. Gluten addition (3% and 1.32%) to brown rice improved conidia production by 14 and 6 times, respectively, relative to brown rice without additives. Conidia cultivated on barley produced a mortality rate of 62% in the sweet potato whitefly after 4-day treatment, compared with 53% for conidia cultivated on brown rice. The amendment of solid substrate cultivation with additives changed the virulence of the conidia produced; the median lethal time ($LT_{50}$) was shorter for conidia produced on barley and brown rice with added yeast extract (1.32% and 3%, respectively), $KNO_3$ (0.6% and 1%), or gluten (1.32% and 3%) compared with conidia produced on substrates without additives.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.99-104
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• 2010

Dead insects infected with fungi were collected from mountains and islands in several locations in Korea from 2003 to 2007. Morphological characteristics of the fungal fruiting bodies produced on the insect samples were examined. A total of 542 entomopathogenic fungal isolates were obtained from the insect samples and identified based on their morphological and cultural characteristics. Three species of Beauveria, eight species of Cordyceps and four species of Isaria were mainly isolated from the insect samples. The other entomopathogenic fungi isolated from the insect samples were Metarhizium anisopliae, Nomuraea rileyi, Paecilomyces sp. and Verticillium sp.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.121-126
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• 2007

Obesity is a major risk factor for cardiovascular disease. In our case study using animal models for disease states such as obesity or hypertension, we found that, Isaria sinclairii remarkably reduced body weight and ameliorated metabolic abnormalities in Zucker and SHR rats. Genetically obese (fa/fa) Zucker rats were one animal model chosen for this study. Four groups of rats received a standard diet and were treated orally with the following test samples daily for 8 weeks: saline (negative control), ethanol extracts of I. sinclairii, hot water extract of I. sinclairii, or $Xenical^{(R)}$ (30 mg/kg, positive control). Mild reductions (6.3%) in body weight gain were observed in the groups treated with the hot water extract of I. sinclairii compared to the control after 8 weeks. Interestingly, organ weight was greatly reduced by this Dongchunghacho (I. sinclairii), in parallel with the mild reductions in body weight gain and reductions in abdominal fat (adipose tissue). Also observed was a 4.1 % decrease in the ratio of heart weight/body weight compared to the control group. As a hypertensive animal model, SHR (spontaneously hypertensive rat) and WKY (Wistar Kyoto) rats were also administered these extracts for one month. Treatment with the hot water extract of I. sinclairii caused greater reductions in body weight gain for the SHR group (10.9%) compared to the WKY group's (5.2%). Based on these results, I. sinclairii extracts contain selective action for anti-obesity activity, naturally occurring candidate for regulation of body weight increase, as demonstrated in the present study.

• Korean Journal of Organic Agriculture
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• v.25 no.3
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• pp.631-642
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• 2017

For effective control of insect pest which can outbreak in a field during crop cultivation, various control agents such as eco-friendly agricultural materials (EFAM) including microbial control agents and chemical pesticides have been applied at fields and these control agents may be treated simultaneous or sequential in the same field to suppress diverse pests and diseases. The agents may influence each other and control efficacy may also differ from interactions. Therefore we need to test compatibility of microbial control agents with other agricultural agents. In this study, we investigated influence of pre-treated EFAMs, which are registered for whitefly control in greenhouse, on germination, mycelial growth and control efficacy of Isaria javanica isolate against sweet potato whitefly. The results showed that a mixture of paraffin oil+cinnamon oil among 4 EFAMs highly reduced germination ($8.9{\pm}1.3%{\sim}24.5{\pm}0.9%$) and mycelial growth ($0.81{\pm}0.01cm{\sim}0cm$) of I. javanica. To investigate the effects of the treatment interval between EFAMs and I. javanica on sweet potato whitefly control, four different EFAMs were pre-treated 0, 1, 4, and 7 days before applying I. javanica. Pre-treatment of four EFAMs inhibited insecticidal activity of I. javanica against sweet potato whitefly. Therefore when EFAMs and a mycopesticide using I. javanica spray simultaneous or sequential, application of EFAMs need more than 7 days interval after treatment of mycopesticide at field.

• Journal of Naturopathy
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• v.8 no.2
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• pp.78-87
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• 2019

Purpose: The aim was to collect and classify the Cordyceps parasitized in cicadas from July to October every year from 1990 to 2016 in Korea. And they were frequently collected in Nepal, Vietnam, Japan, China, and Thailand. Methods: Cordyceps parasitizing cicadas collected in mountains and fields. Results: A total of 1,104 specimens were collected that belonged to 10 different species under nine genera. The highest number of samples belonged to Ophiocordyceps (563 specimens), followed by Isaria (361 specimens), Polycephalomyces (73 specimens), Cordyceps (70 specimens), Beauveria (25 specimens), Perennicordyceps (8 specimens), Metarhizium (2 specimens) and Purpureocillium (2 ones). Among Ophiocordyceps spp. O. longissima was most frequently collected with a total of 426 samples out of 563, followed by O. heteropoda with 120 ones and O. sobolifera with 17 specimens. The species mainly collected in Korea, but C. ishikariensis was collected in Nepal only. The new characteristic was that Isaria cicada-like synnemata were found growing together with C. ishikariensis stromata on the same host. In Korea, the collected 691 specimens in total out of 1,104 were found in Mt. Halla in Jeju Island. Other mountains in Korea where the samples were collected were Mountains Daeryong, Jiri, Yongmoon, Samag, Seolag, Gujeol, Duryun, Baegam, Chilgap, Chundeung, Naejang, Welchul, and Daeryong. The three samples were not identified. Conclusions: A total of 1,104 specimens belonged to 10 different species under nine genera, and the collected 691 samples were found in Mt. Halla in Jeju Island.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10b
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• pp.79-79
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• 2000

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.46-46
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• 2003

The present study examined the effect of alcohol extract of Isaria sinclairii on blood pressure in spontaneously hypertensive rats (SHR). The blood pressure and heart rate were measured after treatment of alcohol extract of Isaria sinclairii by indirect tail cuff method and direct in vivo model. Male SHR were treated with extracts for 2 or 4 weeks starting at 12 weeks of age. (omitted)

• Journal of Sericultural and Entomological Science
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• v.44 no.1
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• pp.28-31
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• 2002

Paecilomyces tenuipes (Nunkkot Dongchunghacho) was erroneously treated in three different scientific names: Paecilomyces japonica, Isaria japonica and Paecilomyces tenuipes. Since the fungus has been widely used in various fields of research and industry, its nomenclatural uncertainty caused many problems. Therefore, morphological studies of Korean isolate were carried out and compared with published data on other isolates of P. tenuipes to establish its proper taxonomic position.

• Research in Plant Disease
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• v.27 no.3
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• pp.99-106
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• 2021

The fungal isolate Isaria javanica pf185 has potential as a mycopesticide because it demonstrates insecticidal activity against the green peach aphid and antifungal activity against Colletotrichum gloeosporioides. For commercialization of this isolate, determination of the optimal and least expensive culture conditions is required; however, these data are not currently available. This study describes the conditions for optimal development of conidia and production of metabolites for the biocontrol of the fungal pathogen. The optimal culture conditions were examined using cultures on solid agar and liquid media. High growth temperature enhanced spore formation but reduced antifungal activity in both solid and liquid media. The highest spore yield was obtained in a medium containing glucose as a carbon source and yeast extract as a nitrogen source. Soybean powder and wheat bran were effective nitrogen sources that promoted spore production and antifungal activity of the isolate. These results revealed the basic, cost-effective growth media for commercial production of a biopesticide with insecticidal and antifungal properties for use in integrated pest management.