• Journal of Photoscience
• /
• v.7 no.2
• /
• pp.39-44
• /
• 2000

To examine the chilling tolerance lipids, we compared the chilling susceptibility of photosystem II of wild type tobacco plants with that of transgenic tobacco plants, in which the sensitivity to chilling had been enhanced by genetic modification of fatty acid unsaturation of chloroplast membrane lipids. The transgenic tobacco plants were found to contain reduced levels of unsaturated membrane fatty acids by being tansformed with cDNA for glycerol-3-phosphate acyltransferase from squash. For the purpose of studying on the functional integrity of photosystem II during low-temperature photoinhibition, the photochemical efficiency was measured as the ration of the maximun fluorescence of chlorophyll (Fv/Fm) of photosystem II. In parallel with an investigation on the transgenic plants, susceptibility of chilling-resistant species, such as spinah and pea, and of chilling-sensitive ones, such as squash and sweet potato, to low-temperature photoinhibition was also compared in terms of room temperature-induced chlorophyll fluorescence from photosystem II. When leaf disks from the two genotypes of tobacco plants were exposed to light at 5$^{\circ}C$, the transgenic plants showed more rapid decline in photochemical activity of photosysytme II than wild-type plants. When they were pretreated with lincomycin, an inhibitor of chloroplast-encoded protein synthesis, the extent of photoinhibition was even more accelerated. More impottantly, they showed a comparable extent of photoinhibition in the presence of lincomycin, making a clear contrast to the discrepancy observed in the discrepancy observed in the absence of lincomycin. Restoration of Fv/Fm during recovery from low-temperature photoinhibition occurred more slowly in the transgenic tobacco plants than the wild-type. These findings are discussed in relation to fatty acid unsaturation of membrane phosphatidylglycerol. It appears that the ability of plants to rapidly regenerate the active photosystem II complex from might explain, in part, why chilling-resistant plants can toleratlow-temperature photoinhibition.

• Korean journal of food and cookery science
• /
• v.22 no.2 s.92
• /
• pp.105-110
• /
• 2006

This study was performed to determine the sensory evaluation and mechanical characteristics of lemon red ginseng-pyun. Lemon red ginseng-pyun was made with lemon juice(21.4%), sweet potato starch(6.7%), water(53.3%), sugar(13.3%), honey(5.3%) and various concentrations of red ginseng powder(0, 2, 4, 6, 8, 10%). The quality characteristics of the sample were estimated in terms of pH, color difference, texture profile analysis and sensory evaluation. The pH of lemon red ginseng-pyun showed no significant difference among the different ratios of red ginseng. With increasing red ginseng powder addition, the lightness was significantly(p<0.05) lower, and a value and b values were significantly(p<0.05) higher. In sensory evaluation, with increasing red ginseng powder addition, the color and bitter taste of lemon red ginseng-pyun were stronger, while clarity of the 10% added red ginseng was significantly(p<0.05) lower than that of the 0% added red ginseng. Elasticity, hardness, chewiness, softness. sweet taste and overall acceptability were not significantly different in any group. In texture profile analysis, chewiness, cohesiveness, gumminess and hardness were significantly(p<0.05) increased in the 10% added red ginseng but springiness was not significantly different in any group. Overall acceptability was related to texture, appearance, overall taste and sweet taste of lemon red ginseng-pyun. Therefore, development of lemon red ginseng-pyun with no sugar or artificial sweeteners is encouraged as a healthy diet for diabetes and hypertension patients, because red ginseng is defined as a functional foods.

• Analytical Science and Technology
• /
• v.30 no.1
• /
• pp.1-9
• /
• 2017

Starch is a mixture of amylose (AMY) and amylopectin (AMP) which are different in physical properties such as molar mass (M), rms radius ($R_g$) and hydrodynamic diameter ($d_H$). The rheological and functional properties of starch are influenced by various factors including the molecular size, molar mass distribution (MD) and the concentration ratio of AMY and AMP. It is also important to analyze proteinaceous material in starch as they affect the flavor and texture of food to which starch is added. In this study, asymmetrical flow field-flow fractionation (AF4) was employed for separation and quantitation of AMY and AMP in starches (Amaranth, potato, taros and quinoa). AF4 was coupled with a multi-angle light scattering (MALS) and a refractive index (RI) detector for determination of the absolute M, MD and molecular structure. It was found that AMP has the M and $R_g$ ranging $3.7{\times}10^7{\sim}6.5{\times}10^8g/mol$ and 84 ~ 250 nm, respectively. Also the existence of branch was confirmed in higher M. In addition, proteinaceous material in starch was analyzed by AF4 coupled with a fluorescence detector (FS) after fluorescence-labeling. AF4-FS with fluorescence-labelling showed a potential for investigation on existence of proteinaceous material and the interaction between proteinaceous material and polysaccharide in starch.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.21 no.1
• /
• pp.48-53
• /
• 2010

Backgraound and Objectives : The voice change can occur in acute epiglottitis or peritonsillar abscess, and the labelings of both changes as a "muffled voice" or "hot potato voice", The aim of this study was to investigate the difference of changes in acoustic feature of voice before and after treatment in patients with acute epiglottitis or peritonsillar abscess. Subjects and Method: 13 patients with acute epiglottitis and 12 patients with peritonsillar abscess were enrolled in the study. Acoustic analysis on sustained Korean vowels /${\alpha}$/, /u/ and /i/ were performed before and after treatment. Results: In patients with acute epiglottitis, the first formant frequency (F1) of /${\alpha}$/ was increased, and the second frequency (F2) of /i/ was decreased. In patients with peritonsillar abscess, F1 and F2 of /${\alpha}$/ were decreased. F1 of /i/ and /u/ were increased, while F2 were decreased. Conclusion : The anatomical and functional changes of oropharynx and larynx by acute epiglottitis and peritonsillar abscess can cause different change in resonance and speech quality. We suggest that these changes could be the cause of 'muffled vocie' in patients of acute epiglottitis or peritonsillar abscess, but different characteristics of phonation in each disease should be distinguished.

• Mycobiology
• /
• v.43 no.4
• /
• pp.415-422
• /
• 2015

The study aimed to evaluate the probiotic properties, antioxidant activity and fermentative capacity of Acremonium charticola and Rhizopus oryzae isolated from the Indonesian fermented dried cassava, with particular application on poultry. A. charticola inhibited the growth of Escherichia coli and Aspergillus flavus. A. charticola and R. oryzae grew in potato dextrose agar (PDA) adjusted to pH 3 and 8 or in PDA supplemented with bile salt up to 0.8%. After soaking for 8 hr, the survival rate of A. charticola in the simulated gastric juice (pH 2) and bile solutions (2% bile salt) was lower than that of R. oryzae. A. charticola and R. oryzae exhibited strong antioxidant activities. Compared to unfermented cassava pulp (control), the fibre content of cassava pulp tended to be lower after fermentation with A. charticola for 14 days. The populations of A. charticola and R. oryzae were significantly higher in fermented cassava pulp than in unfermented one. Coliform was higher in cassava pulp fermented with R. oryzae or A. charticola + R. oryzae compared to control after 7 days of fermentation, however, the bacteria were not different between A. charticola-fermented cassava pulp and control. Lactic acid bacteria (LAB) were higher in A. charticola- and R. oryzae-fermented cassava pulp than those in control, however, no difference of LAB was observed between A. charticola + R. oryzae-fermented cassava pulp and control. In conclusion, A. charticola exhibited antibacterial, antifungal and antioxidant activity, gastrointestinal persistence and fermentative capacity that may be beneficial for poultry industry.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2002.08a
• /
• pp.64-71
• /
• 2002

Rice(Oryza stiva L.) is a major cereal food providing nourishment to over half of the world's populations and was considered only as a source of energy. However, The recent many researches have been made to suggest that rice may relate to prevention chronic disease and health-promoting properties such as postprandial glucose response, hypocholesterolemic effect and blood pressure-lowering effect. There has been numerous observation supporting that rice has hypocholesterolemic effect. Rice, rice bran, rice bran oil and unsaponifiable matter of rice bran oil reduced plasma cholesterol in rat, hamster as well as human. Components of rice showing hypocholesterolemic effect include dietary fiber(hemicellulose, phytic acid). protein, ${\gamma}$-oryzanol, $\beta$-sitosterol, and tocotrienols. Crapo et al has been studied that the effect of various of starchy foods on the postprandial blood glucose and insulin responses in healthy and diabetic humans. The results showed that rice had lower blood glucose and insulin responses compared to potato, bread and dextrose. The different physical forms in the same starch also produce the different postprandial glucose and insulin responses. In recent years, several studies have shown that some components of rice have potent antioxidant activity against Fe$^{2+}$ -ascorbate induced lipid peroxidation in rat liver microsomal membranes. Cell culture and animal studies have shown that some components of rice have inhibitory effect on the growth and proliferation of several types of human cancer cell. It was also reported that the methanol extract of brown rice has antimutagenic activity against various mutagens. In addition, the pepsine hydrolysate from rice protein is reported to inhibit angiotensin converting enzyme activity. GABA (${\gamma}$ - aminobutyric acid) and GABA enriched rice germ is also effective for lowering blood pressure and triglyceride levels.s.

• Culinary science and hospitality research
• /
• v.20 no.3
• /
• pp.80-89
• /
• 2014

This study examined the nutritional components and physicochemical properties of small colored potatoes and small regular potatoes as a natural health food source. To accomplish this, the general and antioxidative contents of small colored potatoes and small regular potatoes were measured. Total contents of carbohydrates, crude protein, crude lipid, and ash were 88.1%, 4.9%, 0.9%, and 6.4%, respectively. Small colored potatoes contained 76.5 kcal, while their total dietary fiber was 4.0%. Total proteins consisted of 17 different kinds of amino acids. Regarding their mineral contents, K was the most abundant mineral, followed by P, Mg, and Ca. Total phenol contents of the 70% ethanolic extracts of small colored potatoes were $48.2{\pm}1.2$ mg GAE/g. Total flavonoid contents of the 70% ethanolic extracts were $13.1{\pm}0.3$ mg RE/g. Overall, small colored potatoes had higher amounts of nutrients and physicochemical properties than small regular potatoes. The general nutrients and other antioxidant bioactive materials in small colored potatoes were also potential materials for good health food. It is expected that follow up studies of small colored potatoes through developing processed food and evaluation of their functional properties would provide useful information as a source of functional foods.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.60 no.3
• /
• pp.343-348
• /
• 2015

Soybean is one of the important food crop around the world. Especially in East Asia, it is the main ingredient for traditional food like soy sauce and soy paste. The double cropping system including soybean following onion, Chinese cabbage, and potato is widely adopted in Southern region of Korea. In this system, sowing date of second crop (soybean) can be delayed depending on first crops' growth period and weather condition. When planting date is delayed it is known that soybean yield is declined because of shorter vegetative growth period and earlier flowering induced by warm temperature and changes in photoperiod. The objective of this study was to determine soybean growth and yield responses as plant populations at late planting date. Field experiment was conducted at Department of Functional Crop, National Institute of Crop Science, RDA located in Miryang, Gyeongsangnam-Do for two years ('13-'14) in upland field with mid-late maturity cultivar Daewon. A split-plot block design was used with three replications. Main plots were three sowing dates from June 20 to July 20 with 15 days intervals, and subplots were 4 levels of planting densities. Data of maturity (R8) was recorded, yield components and yield were examined after harvesting. Experimental data were analyzed by using PROC GLM, and DMRT were used for mean comparison. Optimum planting population for maximizing soybean yield in late planting which compared with standard population. In mid-June planting, higher planting density causes increased plant height and decreased diameter which lead to higher risk of lodging, however, reduced growth period due to late planting alleviated this problem. Therefore higher seeding rates can provide protection against low seedling emergence caused by late planting in this region.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.2
• /
• pp.206-215
• /
• 2020

Trichoderma reesei is the major filamentous fungus used to produce cellulase and there is huge interest in promoting its ability to produce higher titers of cellulase. Among the many factors affecting cellulase production in T. reesei, the mycelial phenotype is important but seldom studied. Herein, a close homolog of the Neurospora crassa COT1 kinase was discovered in T. reesei and designated TrCOT1, which is of 83.3% amino acid sequence identity. Functional disruption of Trcot1 in T. reesei by RNAi-mediated gene silencing resulted in retarded sporulation on potato dextrose agar and dwarfed colonies on minimal medium agar plates containing glucose, xylan, lactose, xylose, or glycerol as the sole carbon source. The representative mutant strain, SUS2/Trcot1i, also displayed reduced mycelia accumulation but hyperbranching in the MM glucose liquid medium, with hyphal growth unit length values decreased to 73.0 ㎛/tip compared to 239.8 ㎛/tip for the parent strain SUS2. The hyperbranching phenotype led to slightly but significantly increased cellulase secretion from 24 to 72 h in a batch culture. However, the cellulase production per unit of mycelial biomass was much more profoundly improved from 24 to 96 h.

• Korean Journal of Food Science and Technology
• /
• v.48 no.4
• /
• pp.361-365
• /
• 2016

This study was conducted to isolate and identify a microorganism that increases tricin-O-(threo-${\beta}$-guaiacylglyceryl) ether (TTGE) content in the hulls of rice (Oryza sativa L.). Bacteria from germinated rice were isolated by enrichment cultivation using yeast mold, luria bertani, potato dextrose and mannitol egg york polymyxin broths. The highest increase in TTGE content ($339.30{\mu}g/g$) was achieved by a microorganism isolated by PDA enrichment cultivation. On the basis of 16S RNA sequence homology and phylogenetic analysis, the isolated bacterium was identified to have 100% similarity with Burkholderia vietnamiensis. The isolated bacteria were short rods, negative for the Gram stain, and positive for the catalase test. The highest TTGE level was $435.86{\mu}g/g$ in 72-h fermented samples, representing a 2.5x increase compared with the control ($175.65{\mu}g/g$). In conclusion, the bacterium isolated from germinated rice extract was Burkholderia vietnamiensis, and the optimum fermentation period to maximize TTGE levels was 72 h. These findings might help in developing functional materials using rice hulls, a waste product of rice milling.