• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.1971-1981
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• 2018

In this study, we investigated the altered enzymatic activities and metabolite profiles of koji fermented using varying permutations of Aspergillus oryzae and/or Bacillus amyloliquefaciens. Notably, the protease and ${\beta}$-glucosidase activities were manifold increased in co-inoculated (CO) koji samples (co-inoculation of A. oryzae and B. amyloliquefaciens). Furthermore, gas chromatography-mass spectrometry (GC-MS)-based metabolite profiling indicates that levels of amino acids, organic acids, sugars, sugar alcohols, fatty acids, nucleosides, and vitamins were distinctly higher in CO, SA (sequential inoculation of A. oryzae, followed by B. amyloliquefaciens), and SB (sequential inoculation of B. amyloliquefaciens, followed by A. oryzae). The multivariate principal component analysis (PCA) plot based on GC-MS datasets indicated a clustered pattern for MA and MB (koji samples inoculated either with A. oryzae or B. amyloliquefaciens) across PC2 (20.0%). In contrast, the CO, SA, and SB metabolite profiles displayed segregated patterns across PLS1 (22.2%) and PLS2 (21.1%) in the partial least-square discriminant analysis (PLS-DA) model. Intriguingly, the observed disparity in the levels of primary metabolites was engendered largely by higher relative levels of sugars and sugar alcohols in MA, SA, and CO koji samples, which was commensurate with the relative amylase activities in respective samples. Collectively, the present study emphasizes the utility of integrated biochemical and metabolomic approaches for achieving the optimal permutation of fermentative inocula for industrial koji preparation.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1649-1657
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• 2006

In order to find an alternative source of inoculum to caecal content for studying the fermentation activity of rabbit hindgut, caecal content and faeces of 25 hybrid Hyla rabbits were used as inocula for an in vitro gas production trial. About 1 g of three substrates (dehydrated alfalfa meal, dehydrated beet pulp, barley) was weighed, in quadruplicate per inoculum, in 120 ml bottles; 75 ml of anaerobic medium and 4 ml of reducing solution were added and bottles were placed at $39^{\circ}C$. Caecal content and faeces were diluted respectively 1:2 (CI) and 1:8 (FI) with anaerobic medium and were introduced in the respective bottles (10 ml). Gas production was recorded 20 times at 2-24 h intervals throughout fermentation (96 h). The fermentation characteristics (i.e. degraded organic matter, OMd; potential gas production, A; fermentation rate, Rmax; time at which it is reached, Tmax; pH, volatile fatty acid, VFA) were studied by inoculum and feedstuffs. The feedstuffs, according to their chemical composition, showed very different fermentation characteristics. In particular, OMd, A and Rmax allowed feedstuff classification as follows: barley>beet pulp>alfalfa. The inocula differ (p<0.05) in Tmax, were higher for CI (15.53 vs. 11.96 h) and in VFA production. In particular, CI produced higher levels of acetate (38.9 vs. 33.4 mM/g OM incubated, p<0.01) and isobutyrate (0.72 vs. 0.42, p<0.01) but less propionate (7.1 vs. 10.3, p<0.01) and butyrate (11.3 vs. 14.0, p<0.01). However, the trend of gas production, similar for the inocula according to the fermented substrate, and the good regression equation to estimate some caecal fermentation parameters from faeces suggest that, after standardisation, the faeces could be used as an alternative inoculum for gas tests in rabbit.

• Journal of Korean Society of Forest Science
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• v.65 no.1
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• pp.43-47
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• 1984

Pinus rigida ${\times}$ P. taeda seedlings in a nursery was inoculated with basidiospores of Pisolithus tinctorius (Pt) either collected from Suweon, Korea or introduced from U.S.A. to compare the effectiveness of the spores from two different origins as mycorrhizal inocula. Nursery beds were fumigated with methyl bromide and 1g of spores was used to inoculate $1m^2$ of soil surface just before seed sowing. Seedlings inoculated with American Pt (#250 strain from Georgia, U.S.A.) were 15% taller than Korean Pt at the end of the first growing season. The seedlings from fumigation treatment only (no inoculation involved) was slightly taller (statistically unsignificant) than those with Korean Pt, but slightly smaller than those with American Pt. In a subsequent year experiment, the seedlings inoculated with American and Korean Pt after soil fumigation were 66% and 60% taller, respectively, than seedlings infected by natural fungi without soil fumigation, suggesting the dual effects of Pt and fumigation on the seedling growth. Therefore potential of Pt spores for an effective inoculum exists and selection of Pt strains which have adapted to specific local environments is needed to develop better sources of mycorrhizal inocula.

• Korean Journal of Microbiology
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• v.34 no.3
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• pp.96-100
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• 1998

The effects of electron acceptors and acclimation of inoculum on the anaerobic degradation of benzene, toluene, and m-xylene (BTX) were investigated to enhance the rate of degradation by estuarine sediment inoculum. With the fresh sediment inocula, degradation of BTX ensued after a 10-week acclimation period, and 37~61% of benzene and 57~61% of toluene were degraded after 16 weeks. Sediments from heavily contaminated sites showed higher degradation rates of BTX. After a 6-month of acclimation, degradation onset rapidly from the time of BTX addition and no difference was found among the sediment inocula. Single compound of BTX was slowly degraded in the methanogenic conditions, however, the degradation of BTX mixture was slow in the denitrifying conditions. Although the degradation rate of m-xylene was the fastest among the components of BTX mixture, longer acclimation enhanced the degradation rate of BTX, especially that of benzene. When the culture fluids were tested with Microtox, anaerobic degradation of BTX reduced the toxicity of BTX as well.

• The Journal of Korean Society of Virology
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• v.28 no.1
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• pp.63-69
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• 1998

To establish in vivo antiviral evaluation system by using murine herpesvirus intracerebral infection model, 5-6 female BALB/c mice per group aged 5 weeks were inoculated i.c. into cerebrum with different inocular HSV-1 F. Signs of clinical disease noted everyday for one month. Observed were body weight decrease, neurological signs and death caused by encephalitis. Mice discontinued body weight decrease were recovered from the disease, and keratitis was often observed during recovery. The groups inoculated with higher than 1,000 PFU showed 100% mortaltiy and $LD_{50}$ was <100 PFU/mouse. To study the effect of virus inoculum sizes on antiviral effect of acyclovir (ACV), mice inoculated with different inocula were administered i.p. with different doses of ACV immediately after infection, and twice a day for 5 days. The higher inculum size, the less protective. $ED_{50}$ of ACV was >25, >25, 18.4 and 8.0 mg/kg b.i.d. in the group infected with 1,000,000, 100,000, 10,000 and 1,000 PFU/mouse, respectively. $LD_{50}$ of ACV was 62.5 mg/kg b.i.d. Therapeutic index of ACV was <2.5, <2.5, 3.0 and 7.0 in the groups with inocula 1,000,000, 100,000, 10,000 and 1,000 PFU/mouse, respectively. Inoculum size 1,000 PFU/mouse showing 100% mortaltiy and 5-6 days mean time to death, 5 days drug administration and 14 days observation will be future experimental conditions.

• Research in Plant Disease
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• v.11 no.1
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• pp.16-20
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• 2005

Several time-course experiments were carried out to understand seasonal development of melanose on yuzu trees at koehung area, Jeonnam province, during May to October. The occurrence of dead twigs, known as a source of infection, was much more in older trees, and from June to August, mostly in July. In the experiment of pycnidia development on dead twigs seasonally collected, the number of developed pycnidia was highest on July-collected dead twigs especially with the diameter of 1.1~1.5 cm. In the collection survey of disseminated pycnidiospores, although the collected number of pycnidiospores was affected with amount of precipitation, the number of observed pycnidiospores in rainwater was relatively high from June to August, with highest in early August in 1997 and late July in 1998. In the inoculation tests on 3-year-old trees and fruits in natural condition, disease occurrences were mostly affected on twigs by inocula treatment in June, and on fruits by inocula treatment in July, respectively.

• Research in Plant Disease
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• v.10 no.2
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• pp.87-93
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• 2004

Rhizome rot of ginger, caused by Pythium myriotylum, a major limiting factor for its production, has occurred annually, but become severe, especially in hot and humid years with frequent rainfalls in Korea. Most studies on rhizome rot have been carried out since 1980s in the National Institute of Agricultural Sciences and Technology, Honam Crop Experimental Station and Choongnam Provincial Rural Development Administration. Many aspects of rhizome rot, such as survey of the disease incidence, taxonomy, pathogenicity and physiology of pathogen, and ecology of soilborne inocula have been studied in the researches. However, intensive studies have been concentrated on management technologies of the disease including seed-rhizome disinfection, soil sterilization, evaluation of cultivar resistance, and fungicide application, and most developed technologies have been used in commercial farmings. In future, development of resistant varieties and simple soil disinfection technologies applicable in Korean condition and economically feasible fungicide application technology have to be developed for better management.

• The Plant Pathology Journal
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• v.18 no.5
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• pp.279-283
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• 2002

Biological control of Fusarium udum causing wilt disease of pigeonpea was studied in vitro, as well as, in vivo. Aspergilluspavus, Anergillus niger, Bacilius licheniformis (strain-2042), Gliocladium virens, Peniciliium citrimum, and Trichoderma harzianum, which were found to be the most potent ones in inhibiting the radial colony growth of the test pathogen, were used as biological control by amending their inocula at diffeyent concentrations in pots and in pathogen-infested soil in the fields. Maximum reduction of the wilt disease was observed with G. vireos both in pots and in the fields. The population of E. udum was found to be markedly reduced when the antagonists were applied in the soil. The study establishes that G. virens can be exploited for the biological control of wilt disease at field level.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.722-726
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• 2005

The use of isolated wine yeasts in winemaking processes is preferable to spontaneous fermentation. Selection criteria of wine yeast strains depend also on capacity and rate of fermentation and on alcohologenic capabilities. Our studies have described the dynamics of fermentation of wine musts by some isolated wine yeast strains of Saccharomyces genus: strains 6 and 8 of S. cerevisiae var. ellipsoideus (S. ellipsoideus) and strains 5 and 7 of S. bayanus var. oviformis (S. oviformis). All have high technological properties and all are adapted for the specific pedoclimatic conditions of some areas of Sibiu viticultural region. The selected strains were used as inocula to ferment Sauvignon, Muscat Ottonel, Rose Traminer, and Pino Gris musts in controlled laboratory conditions. It was found that higher initial oxygen concentration in must is necessary to accelerate the fermentation of all the wine yeast strains studied. In order to obtain quality wines, strains with considerable fermentative capacity, high alcohologenic capabilities, and a good conversion efficiency are recommended.

• Mycobiology
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• v.34 no.4
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• pp.191-195
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• 2006

This study was conducted to investigate the different effects of ectomycorrhizal fungal (ECMF) species on the growth of seedlings of Pinus densiflora, and the effects of ECMF diversity on plant productivity. A total of five species of ECMF were isolated from root tips of pine seedlings collected from Mt. Songni and used as inocula. Pots containing pine seedlings were inoculated with either a single ECMF species or a mixture of five ECMF species. All of the seedlings formed ECM on their roots except for the control plants. The pine seedlings' growth responses varied by the different ECMF species. Also, pine seedlings inoculated with a mixture of five ECMF species showed the highest growth response. The results of the study suggest that the colonization of diverse species of ECMF will increase plant productivity, and the selection of suitable ECMF species could be an important factor for plant growth.