• Journal of Microbiology
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• v.44 no.1
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• pp.113-120
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• 2006

Candida tropicalis was treated with ultraviolet (UV) rays, and the mutants obtained were screened for xylitol production. One of the mutants, the UV1 produced 0.81g of xylitol per gram of xylose. This was further mutated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and the mutants obtained were screened for xylitol production. One of the mutants (CT-OMV5) produced 0.85g/g of xylitol from xylose. Xylitol production improved to 0.87 g/g of xylose with this strain when the production medium was supplemented with urea. The CT-OMV5 mutant strain differs by 12 tests when compared to the wild-type Candida tropicalis strain. The XR activity was higher in mutant CT-OMV5. The distinct difference between the mutant and wild-type strain is the presence of numerous chlamvdospores in the mutant. In this investigation, we have demonstrated that mutagenesis was successful in generating a superior xylitol-producing strain, CT-OMV5, and uncovered distinctive biochemical and physiological characteristics of the wild-type and mutant strain, CT-OMV5.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.1-14
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• 2016

Heat stress is an agricultural problem for Gerbera jamesonii, and it often causes poor seedling growth, reduced flower yield and undesirable ornamental characteristics of flowers. However, little is known about the effect of heat stress on the morphological, physiological and biochemical characteristics of gerbera plants. Here, the responses of six cultivars of Gerbera jamesonii to heat stress were investigated. Under a 1-d heat treatment at $45^{\circ}C$, the leaves of gerbera cultivars showed yellowing, wilting, drying and death to varying degrees. The heat treatment also resulted in increased electrical conductivity, decreased soluble protein and chlorophyll contents, and the accumulation of malondialdehyde (MDA) and proline in leaves. Moreover, heat tolerance differed among the six tested gerbera cultivars. Our results demonstrated that among the six gerbera cultivars, 'Meihongheixin' is a heat-resistant cultivar, whereas 'Beijixing' is a heat-sensitive one. 'Shijihong' and 'Linglong' are relatively heat-resistant cultivars, and 'Dadifen' and 'Taiyangfengbao' are relatively heat sensitive.

• Korean Journal of Agricultural Science
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• v.45 no.1
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• pp.50-57
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• 2018

Meat comes from the skeletal muscles of farm animals, such as pigs, chickens, and cows. Skeletal muscles are composed of many muscle fibers. Muscle fibers are categorized into three types, fiber type I, IIA, and IIB, based on their contractile speed and metabolic properties. Different muscle fiber types have different biochemical, physiological, and biophysical characteristics. Especially, the characteristics of muscle fiber type I and IIB are opposite to each other. Muscle fiber type I has a relatively strong oxidative metabolic trait and a higher content of lipids. In contrast to fiber type I, muscle fiber type IIB has a strong glycolytic metabolic trait and a relatively lower content of lipids and a higher content of glycogen. Muscle fiber type IIA has intermediate properties between fiber type I and IIB. Thus, muscles with different fiber type compositions exhibit different ante- and post-mortem muscle characteristics. In particular, the different metabolic traits of muscles due to the different compositions of the fiber types strongly affect the biochemical and physiological processes during the conversion of muscle to meat and subsequently influence the quality of the meat. Therefore, understating muscle metabolism and muscle fiber characteristics is very important when discussing the traits of meat quality. This review is an overview on basic muscle metabolism, muscle fiber characteristics, and their influence on meat quality and finally provides a comprehensive understanding about the fundamental traits of muscles and meat quality.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.1-12
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• 2002

Ecophysiologically diapause represents a syndrome of physiological and biochemical characteristics, all of which ensure survival during a long period of dormancy. Since, silkworm enters diapause as embryo at the early embryonic stage, the duration of egg life depends on the duration of embryonic diapause. The nature of diapause in silkworm, Bombyx mori, is primarily determined by genetic characters and endocrinologicnl mechanisms, mediated by environmental factors such as temperature and photoperiod. Hibernating potency value besides nucleic acid and carbohydrate metabolism, production and utilization of sorbitol are also equally responsible for induction, initiation, determination, maintenance and termination of diapause. Embryonic diapause in Bombyx moir, induced by active secretion of sub-oesophageal ganglion is attributed to hormonal system and metabolic adjustment, which serves to bring about a new physiological state. Metabolic conversion of trehalose to glycogen at induction, glycogen to sorbitol at initiation and sorbitol to glycogen at termination of diapause is correlated and in each metabolic shift a key enzyme becomes active in response to hormonal and environmental stimulation. An attempt has been made in this review article to discuss briefly the nature of embryonic diapause, influence of various factors on diapause nature, hormonal mechanism of diapause besides biochemical composition of egg, nucleic acid and carbohydrate metabolism, production and utilization of sorbitol in relation to induction, determination, maintenance, initiation and termination of diapause in the silkworm, Bombyx mori.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.123-127
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• 1982

Fourteen isolates of Pseudomonas solanarearum virulent to tobacco cultivars were selected among isolates obtained from tobacco plants shelving wilt symptoms throughout the country during $1980\~1981$. The fourteen isolates were classified into two races based on reactions in eggplant, tomato, red pepper, potato and tobacco, and also classified into biochemical type 1 and type 4 according to physiological characteristics.

• KSBB Journal
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• v.14 no.2
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• pp.198-204
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• 1999

Asymbiotic bacterium with highly effective toxins was isolated from entomopathogenic nematode Steinernema glaseri which has been widely used against various soil-inhabiting pests. The symbiont of S. glaseri was identified as Xenorhabdus nematophilus sp. by using several biochemical and physiological tests. When this strain was released into the hemolymph of insect larva, it produced highly toxic substances and killed the larva within 2 days. Two colony forms that differed n some biochemical characteristics were observed when cultures in vitro. Phase l colonies were mucid and difficult to be dispersed in liquid. Phase II was not mucoid and was easily dispersed in liquid. It did not adsorb neutral red or bromothymol blue. Rod-shaped cell size was highly variable between two phases, ranging 2-10 ${\mu}{\textrm}{m}$. It was also found that only infective-stage nematodes can carry only primary-phase Xenorhabdus in their intestine.

• Journal of Korean Society of Forest Science
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• v.112 no.1
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• pp.57-70
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• 2023

In recent years, the frequency of warnings about particulate matter (PM) has gradually increased in Korea, along with an increase in its intensity. Because of their vast surface area, reactivity to external particles, and characteristics of their leaves, urban trees can act as biofilters, reducing PM pollution. However, the air pollutant PM can cause various types of damage not only to human health but also to vegetation. Studies performed to date on the responses of trees to PM are still insufficient. Here, we analyzed the correlation between PM adsorption and physiological and biochemical responses of four major street tree species, namely, Abies holophylla, Acer buergerianum, Pinus densiflora, and Quercus variabilis, under conditions of approximately 300 ㎍ m^-3 of fly ash emissions using a phytotron. The results showed that the physiological and biochemical responses and PM adsorption differed depending on the tree species. In correlation analysis, it was confirmed that there were positive correlations between physiological factors, and PM adsorption on adaxial leaf surfaces negatively impacted the physiological characteristics. This study provides fundamental information for selecting tree species to reduce PM pollution and develop sustainable urban forests.

• Food Science and Preservation
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• v.5 no.2
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• pp.191-197
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• 1998

Garlic is an important condimental vegetable which has many minerals and numerous organic sulfur compounds. Owing to these components, garlic has many medicinal properties and physiological activities on human health. It can lower sect lipid levels and reduce the severity of cholesterol-induced atherosclerosis. And it appeals to protect against mutagenic and carcinogenic effects. Today's our eating habit is concentrated on the physiological function in floods rather than their taste or mutagenic. To improve garlic's value as a flood or a vegetable, further scientific researches about its volatile and nonvolatile sulfur compounds through the biochemical approach are needed. In addition to that, both areas that the development of garlic-processed goods and utilization of garlic as materials for medicine must be actively studied.

• Journal of Animal Reproduction and Biotechnology
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• v.39 no.1
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• pp.12-18
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• 2024

Background: Somatic cell nuclear transfer (SCNT) is a prominent technology that can preserve superior genetic traits of animals and expand the population in a short time. Hematological characters and endocrine profiles are important elements that demonstrate the stability of the physiological state of cloned animals. To date, several studies regarding cloned camels with superior genes have been conducted. However, detailed hemato-physiological assessments to prove that cloned camels are physiologically normal are limited. In this study, We evaluated the hemato-physiological characteristics of cloned male and female dromedary camels (Camelus dromedaries). Methods: Therefore, we analyzed variations in hematological characteristics and endocrine profiles between cloned and non-cloned age-matched male and female dromedary camels (Camelus dromedaries). Two groups each of male and female cloned and non-cloned camels were monitored to investigate the differences in hemato-physiological characteristics. Results: All the animals were evaluated by performing complete blood count (CBC), serum chemistry, and endocrinological tests. We found no significant difference between the cloned and non-cloned camels. Furthermore, the blood chemistry and endocrine profiles in male and female camels before maturity were similar. Conclusions: These results suggest that cloned and non-cloned camels have similar hematological characteristics and endocrine parameters.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.1-7
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• 1999

The grain rot of caused by Bukholderia glumae was fist reported in japan in 1955 and then reported in other countries as well as in Korea in 1986. The pathogen causes both seedling and grain rot of rice but it cannot attack any other parts of adult rice plant. Bacterial colonies grow slowly, and are circular and greyish white. The causal bacterium is Gram-negative and rod shape with 1-3 polar flagella, and produce a diffusible yellow-greenish nonfluorescent pigment on King's medium B. Biochemical characteristics such as negative in arginine dehydrolase, oxidase reaction and nitrate reduction and positive in lecithinase, and the utilization of L-arginine and inositol are useful in differentiation of this from other nonfluorescent bacteria pathogenic to rice. This pathogenic bacterium had belonged to the genus of Pseudomonas but recently was transferred to the new genus Burkholderia on the basis of physiological characteristics and DNA-DNA hybridization data. However, other characteristics such as colony heterogenicity or colonial variation after subcultures, phytotoxin, secreting antibiotics, and relationship between yellow greenish pigment production and pathogenicity need to be clarified more. To develop an effective control strategy for this disease, understanding of detailed life cycle of the disease and critical environmental factors affecting disease development is prerequisite. Although 5,435 ha of rice paddy in Korea was infested during 1998, there is no exact estimation of yield losses and distribution of the pathogen. The review will focus on recent progress on the understanding of the bacteriological and ecological characteristics of the causal bacterium and control means of the disease.