• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.15-32
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• 2002

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s-1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great progress and success was obtained in development of high-quality japonica cultivars and quality evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice cultivars and special rices adaptable for food processing such as large kernel, chalky endosperm, aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer, Recently, new special rices such as extremely low-amylose dull or opaque non-glutinous endosperm mutants were developed. Also, a high-lysine rice variety was developed for higher nutritional utility. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and texture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak, hot paste and consistency viscosities of viscosities with year difference. The high-quality rice variety "IIpumbyeo" showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic microscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high probability of determination. The $\alpha$-amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were IIpumbyeo, Chucheongyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tonsil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice breed. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large grain rices showed better suitability far fermentation and brewing. The glutinous rice were classified into nine different varietal groups based on various physicochemical and structural characteristics of endosperm. There was some close associations among these grain properties and large varietal difference in suitability to various traditional food processing. Our breeding efforts on improvement of rice quality for high palatability and processing utility or value-adding products in the future should focus on not only continuous enhancement of marketing and eating qualities but also the diversification in morphological, physicochemical and nutritional characteristics of rice grain suitable for processing various value-added rice foods.ice foods.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.27-28
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• 2014

Beauveria bassiana (Cordycipitaceae, Hypocreales, Ascomycota) is an anamorphic fungus having a potential to be used as a biological control agent because it parasitizes a wide range of arthropod hosts including termites, aphids, beetles and many other insects. A number of bioactive secondary metabolites (SMs) have been isolated from B. bassiana and functionally verified. Among them, beauvericin and bassianolide are cyclic depsipeptides with antibiotic and insecticidal effects belonging to the enniatin family. Non-ribosomal peptide synthetases (NRPSs) play a crucial role in the synthesis of these secondary metabolites. NRPSs are modularly organized multienzyme complexes in which each module is responsible for the elongation of proteinogenic and non-protein amino acids, as well as carboxyl and hydroxyacids. A minimum of three domains are necessary for one NRPS elongation module: an adenylation (A) domain for substrate recognition and activation; a tholation (T) domain that tethers the growing peptide chain and the incoming aminoacyl unit; and a condensation (C) domain to catalyze peptide bond formation. Some of the optional domains include epimerization (E), heterocyclization (Cy) and oxidation (Ox) domains, which may modify the enzyme-bound precursors or intermediates. In the present study, we analyzed genomes of B. bassiana and its allied species in Hypocreales to verify the distribution of NRPS-encoding genes involving biosynthesis of beauvericin and bassianolide, and to unveil the evolutionary processes of the gene clusters. Initially, we retrieved completely or partially assembled genomic sequences of fungal species belonging to Hypocreales from public databases. SM biosynthesizing genes were predicted from the selected genomes using antiSMASH program. Adenylation (A) domains were extracted from the predicted NRPS, NRPS-like and NRPS-PKS hybrid genes, and used them to construct a phylogenetic tree. Based on the preliminary results of SM biosynthetic gene prediction in B. bassiana, we analyzed the conserved gene orders of beauvericin and bassianolide biosynthetic gene clusters among the hypocrealean fungi. Reciprocal best blast hit (RBH) approach was performed to identify the regions orthologous to the biosynthetic gene cluster in the selected fungal genomes. A clear recombination pattern was recognized in the inferred A-domain tree in which A-domains in the 1st and 2nd modules of beauvericin and bassianolide synthetases were grouped in CYCLO and EAS clades, respectively, suggesting that two modules of each synthetase have evolved independently. In addition, inferred topologies were congruent with the species phylogeny of Cordycipitaceae, indicating that the gene fusion event have occurred before the species divergence. Beauvericin and bassianolide synthetases turned out to possess identical domain organization as C-A-T-C-A-NM-T-T-C. We also predicted precursors of beauvericin and bassianolide synthetases based on the extracted signature residues in A-domain core motifs. The result showed that the A-domains in the 1st module of both synthetases select D-2-hydroxyisovalerate (D-Hiv), while A-domains in the 2nd modules specifically activate L-phenylalanine (Phe) in beauvericin synthetase and leucine (Leu) in bassianolide synthetase. antiSMASH ver. 2.0 predicted 15 genes in the beauvericin biosynthetic gene cluster of the B. bassiana genome dispersed across a total length of approximately 50kb. The beauvericin biosynthetic gene cluster contains beauvericin synthetase as well as kivr gene encoding NADPH-dependent ketoisovalerate reductase which is necessary to convert 2-ketoisovalarate to D-Hiv and a gene encoding a putative Gal4-like transcriptional regulator. Our syntenic comparison showed that species in Cordycipitaceae have almost conserved beauvericin biosynthetic gene cluster although the gene order and direction were sometimes variable. It is intriguing that there is no region orthologous to beauvericin synthetase gene in Cordyceps militaris genome. It is likely that beauvericin synthetase was present in common ancestor of Cordycipitaceae but selective gene loss has occurred in several species including C. militaris. Putative bassianolide biosynthetic gene cluster consisted of 16 genes including bassianolide synthetase, cytochrome P450 monooxygenase, and putative Gal4-like transcriptional regulator genes. Our synteny analysis found that only B. bassiana possessed a bassianolide synthetase gene among the studied fungi. This result is consistent with the groupings in A-domain tree in which bassianolide synthetase gene found in B. bassiana was not grouped with NRPS genes predicted in other species. We hypothesized that bassianolide biosynthesizing cluster genes in B. bassiana are possibly acquired by horizontal gene transfer (HGT) from distantly related fungi. The present study showed that B. bassiana is the only species capable of producing both beauvericin and bassianolide. This property led to B. bassiana infect multiple hosts and to be a potential biological control agent against agricultural pests.

• Research in Plant Disease
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• v.14 no.3
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• pp.171-175
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• 2008

The influence of rice bacterial leaf blight (BLB) disease incidence on yield and quality of Nampyung, Gang-baek and Iksan493 was investigated in three areas, Gimje, Yeongam and Jangheung, frequently found BLB infested rice. The infection rate of Nampyung, susceptible to BLB disease, was higher ($23{\sim}93%$) than Gang-baek ($2{\sim}15%$) and Iksan493 ($2{\sim}6%$), have resistant gene Xa7 and xa5, respectively. BLB disease incidence was severely found in Gimj and then yield of Nampyung was reduced 65% (352 kg/10a) compared to Iksan493 (540 kg/10a) due to the decrease in the ripen grain filling, brown/rough ratio and 1,000 grain weight. There was no difference of rice yield among Nampyung, Gangbaek and Iksan493 in Yeongam and Jangheung. The occurrence time of disease in Yeongam and Jangheung was later than Gimje and BLB disease was less infected in these areas. BLB infected rice grain showed inferior grain appearance and taste index to sound grain. independent of rice with resistant gene. In Yeongam and Jangheung, Gangbaek and Iksan493 cultivated showed lower ratio of white color to belly than Nampyung. Iksan493 showed better grain appearance and lower ratio of white core to belly than Gangbaek. In protein content of rice grain, the range of Gangbaek and Iksan493 was $6.9{\sim}9.8%$, but Nampyung showed unstable ranged from undetermined to 9.0%.

• Korean Journal of Organic Agriculture
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• v.19 no.1
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• pp.55-64
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• 2011

To investigate a comparison of rice yield and quality by a utilization of green crops using barley and hairyvetch, this study was carried out in rice (Oryza sativa L.) organic cultivation field. Convention barley harvest (CBH), Green barley crop (GBC), Green barley+Green Hairyvetch crop (GB+HVC), and Non-Green crop (NGC) were treated in rice cultivation field. The results obtained as following: 1) Culm length and pancile length in Convention barley harvest (CBH) cultivation were longer than organic cultivation but were not significant difference in all treatments. Yields of milled rice in Green barley crop (GBC) and Green barley+Green Hairyvetch crop (GB+HVC) were by 90.3% and 95.9%, respectively. 2) Protein contents in Green barley crop (GBC) and Green barley+Green Hairyvetch crop (GB+HVC) were by 5.7% lower than 6.6% in Convention barley harvest (CBH) cultivation. Amylose contents in all treatment were similar as range 18.8% to 19.1%. Whiteness contents in Green barley crop (GBC) and Green barley+Green Hairyvetch crop (GB+HVC) were slightly higher by 38.9% and 39.1%, respectively, than 37.7% in Convention barley harvest (CBH) cultivation. 3) Palatability values in Barley harvest (BH) and Non-Green crop (NGC) were slightly higher by 82.0 and 83.8, respectively, than 77.6 in Convention barley harvest (CBH) cultivation. 4) Head rice in Non-Green crop (NGC) was 95.5%, while that of Convention barley harvest (CBH), Green barley crop (GBC), and Green barley+Green Hairy-vetch crop (GB+HVC) were slightly low as range 93.8% to 94.2%. White core and belly rice in Convention barley harvest (CBH) cultivation was the highest level by 1.7%. 5) Leaf blast, neck blast, sheath blight, rice stem maggot, rice leaf roller, rice leaf-tier, and green rice leafhopper were occurred lightly in rice field.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.683-693
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• 2009

This study was designed to investigate the effect of dandelion juice supplementation on attenuation of oxidative stress and hangover after drinking alcohol in healthy college male students. This human trial was conducted by two phase cross over design with two weeks wash out period. The subjects (age $24{\sim}28$ years) were volunteers who had more than 72 g of ethanol drinking capacity. Dandelion group was given dandelion juice 220 mL daily for 7 days. Biochemical markers were determined in blood samples taken at 0 and 150 minutes after administration 72 g of alcohol. The levels of plasma glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, lactate dehydrogenase and bilirubin, the indicators of liver cell damage, were not significantly different between groups. No significant differences in lymphocyte DNA damage level between groups was observed. However, plasma acetaldehyde dehydrogenase (ALDH) and high density lipoprotein cholesterol levels were significantly (p<0.01) increased in dandelion supplemented group compared to that of control group. Furthermore, activities and protein expressions of glutathione-reductase and catalase of erythrocytes were significantly elevated in dandelion supplemented group compared to that of control group. From the above results, it is concluded that dandelion juice supplementation can reduce oxidative stress and hangover syndrome through the elevation of ALDH and antioxidative enzyme system in healthy male adults.