• Research in Plant Disease
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• v.22 no.4
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• pp.297-302
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• 2016

Tomato yellow leaf curl virus (TYLCV) is a viral disease causing severe economic losses on tomato. Practical prevention of the TYLCV disease is to control tabacco whitefly (Bemisia tabaci) or to cultivate TYLCV-resistant tomato cultivars, because no agrochemical products are available to control TYLCV. In this study, TYLCV resistance of the commercial tomato cultivars were evaluated using the DNA markers tightly linked to TYLCV resistance genes Ty-1 and Ty-3 and infection with the TYLCV clones mediated by Agrobacterium. In marker genotyping, resistance alleles were detected from 4 oval type tomato cultivars (Titichal, TY tinny, TY saengsaeng II, TY sense Q). Four cheery type cultiavrs (TY endorphin, TY smartsama, Tiara TY, Olleh TY) and 6 round type cultivars (TY kingdom, TY ace, TY homerun, TY altorang, Dotaerang TY winner, Styx TY). The seedling bioassay indicated that tomato cultivars of the oval type and cherry type showed consistancy in marker genotype and phenotype while slight disease symptom was observed from some round type cultivras (TY ace, TY homerun, Styx TY) with resistance marker genotype. For fruit yields, TY tinny was greater than its control cultivar Titichal in oval types, TY smartsama was greater than its control Smile in cherry type, and TY ace and TY kingdom were greater than their control Dabok. These cutliavrs can be a good choice for high-yielding TYLCV-resistant tomato cultivars.

• Food Science of Animal Resources
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• v.40 no.5
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• pp.722-733
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• 2020

This study was aimed to investigate the physicochemical properties, texture, and antioxidant, and antimicrobial activities of regular-fat sausages (RFSs) mixed with 0.25 and 0.5% of oven-dried and freeze-dried grape tomato powder (GTP, 150 ㎛) during storage at 4℃. RFSs were made by six treatments that included: control (CTL), REF (sausages with 0.1% ascorbic acid alone), F1GTPSs (F1) and F2GTPSs (F2) (sausages with 0.25% and 0.5% freeze-dried GTP), and O1GTPSs (O1) and O2GTPSs (O2) (sausages with 0.25% and 0.5% GTP oven-dried at 100℃). Sausages with added oven-dried grape tomato powders (OGTPs) showed decreased pH, lightness (L^⁎), total plate count (TPC), and thiobarbituric acid-reactive substances (TBARS) compared to the sausages mixed with freeze-dried GTP (FGTPSs), but also had the highest redness (a^⁎) and yellowness (b^⁎) values among the treatments. With increasing levels of GTP, the hardness and chewiness of the sausages gradually decreased and these were decreased more in the FGTPSs (F) than in the OGTPSs (O). Compared to the FGTPSs, OGTPSs had higher antioxidant and antimicrobial activities, which extend the shelf-life of meat products. Application of OGTP to RFSs resulted in higher lipid antioxidant, antimicrobial activities, improving physicochemical properties and extended the shelf-life.

• Food Science and Preservation
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• v.20 no.4
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• pp.451-458
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• 2013

The purpose of this research is to distinguish the quantitative determination of phytochemicals in various agricultural products and to optimize an HPLC method for the determination of lycopene, lutein, ${\alpha}$-carotene, ${\beta}$-carotene, and cryptoxanthin. Among the different conditions studied, the most suitable ones for our samples were the extraction with hexane/acetone/ethanol (50:25:25, v/v/v), dissolution of the dry extract in tetrahydrofuran/acetonitrile/methanol (15:30:55, v/v/v), injection on a $C_{18}$ column with methanol/acetonitrile (90:10, v/v) + triethylamine $9{\mu}M$ as mobile phase, and ${\lambda}_{detection}$=475 nm. The mean percent recovery for the HPLC method were $120.7{\pm}4.1%$ (lycopene), $89.2{\pm}3.5%$ (lutein), $91.2{\pm}2.9%$ (${\alpha}$-carotene), $99.1{\pm}4.4%$ (${\beta}$-carotene), and $100.0{\pm}5.3%$ (cryptoxanthin). The contents of lutein in the agricultural products were spinach, kiwi, tomato, blueberry, melon, respectively. However, the lycopene contents were the highest in the Black tomato ($56.66{\pm}7.48mg/kg$) and Jangseong tomato ($50.28{\pm}5.42mg/kg$). The concentration of ${\beta}$-carotene in all of the agricultural products ranged from 0.07 mg/kg to 65.03 mg/kg. The quercetin content of the agricultural products increased in the order of blueberry (986.57~1,054.06 mg/100 g), kiwi (44.96~55.09 mg/100 g), hallabong (31.92~35.60 mg/100 g), and tomato (26.38~34.94 mg/100 g). The highest kaempferol content was found in the blueberry (47.79~76.15 mg/100 g) with results in all of the tested samples varying between 6.54~48.11 mg/100 g. The total polyphenol contents of the various agricultural products increased in the blueberry (213.60~229.96 mg/100 g), spinach (112.50~141.67 mg/100 g) and kiwi (46.49~70.44 mg/100 g). The total flavonoid content was the highest in both blueberry and spinach. Vitamin C content was detected in kiwi > hallabong > tomato > blueberry, respectively. The total anthocyanin contents (TAC) was detected in the Damyang blueberry and the imported blueberry.

• Korean Journal of Organic Agriculture
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• v.16 no.2
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• pp.151-171
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• 2008

The objective of this paper is to evaluate the feasibility of exporting Korean organic agricultural products to Japanese market. To achieve the objective, we explored the marketing trend of organic agricultural products in Japan and surveyed marketing dealers and food processors that deal with organic foods. We also analyzed Korean farmers' intention of acquiring organic Japanese Agricultural Standard(JAS) certificate in order to export organic agricultural products. The results show that mini tomato is economically feasible to acquire organic JAS certificate but other agricultural products need more attentions. The results also suggest that the education of production and safety management using the international standards such as Japanese Agricultural Standard should be strengthened by local government to promote export of organic agricultural products. The paper implies that producers acquiring organic Japanese Agricultural Standard should be systematization to get larger scale and to guarantee the stability in export supply.

• Food Science of Animal Resources
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• v.37 no.2
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• pp.242-253
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• 2017

This study was performed to evaluate antioxidant activity of tomato powder extracted by various concentrations of ethanol (0, 25, 50, 75, 100%) and to evaluate the physicochemical properties and antioxidant activities of pork patties with ethanol extracted tomato (EET) powder. No differences in the contents of total of individual phenolic compounds including gallic acid and catechin, were observed among the treatments (p>0.05). Among the various concentrations, 50% and 75% EET powder showed the highest free radical scavenging and iron chelating activities (p<0.05). Lipid peroxidation was retarded in linoleic acid emulsion with the addition of 50% and 75% EET powder (0.1%). Based on the model study, five pork patties were actually manufactured; control patty, reference patty with 0.01% of butylated hydroxytoluene, patty with 1% of water extracted tomato (WET), and patties with 0.5 and 1.0% of EET. Addition of 1% WET and EET decreased pH value, and increased redness values of pork patties, as compared to the control (p<0.05). Pork patties with WET (1.0%) and EET (0.5% and 1.0%) had lower 2-thiobarbituric acid reactive substances values compared with control patties after 7 d of storage (p<0.05). Pork patties containing EET powder showed lower total bacterial and Enterobacteriaceae counts than control patties (p<0.05). In conclusion, WET and EET (50%) could be used as a natural antioxidant and antimicrobial agent in meat products.

• Korean Journal of Environmental Biology
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• v.38 no.3
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• pp.486-495
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• 2020

We surveyed disease outbreak status that has recently become a problem in organic tomatoes and cucurbit in plastic greenhouse that were grown without spraying pesticides during the plastic greenhouse growing season of 2015 to 2019. It was found that the incidence of leaf mold, tomato spotted wilt virus, and tomato chlorosis virus disease was severe in tomato, and disease incidence of powdery mildew and zucchini yellow mosaic virus were severe in Cucurbit. The disease outbreak was found to be faster and more severe in crops grown in pesticide-free cultivation plastic greenhouses than in plastic greenhouses that are cultivated in general using pesticides. In particular, the occurrence of viral diseases mediated by thrips and aphids was found to be severely damaged. Therefore, in order to produce good organic products, it is important to effectively control pests, and in order to minimize the damage caused by disease, sanitation and physical blocking, and comprehensively utilize organic materials or microorganisms to prevent them.

• Research in Plant Disease
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• v.14 no.1
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• pp.32-36
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• 2008

Bacterial wilt caused by Ralstonia solanacearum has become a severe problem on tomato in Korea and no effective control measures are available yet. Pseudomonas species play key roles for the biocontrol of many plant diseases especially in soil. A rhizobacterial population of 150 Pseudomonas strains, isolated from the rhizosphere soil of various plants grown at different sites, was screened for 2,4-diacetylphloroglucinol producing gene (PhlD) by PCR. Two strains (P83 and P84) among them were found to be phlD positive. When the isolates were analysed by 16S rDNA (Sensu Stricto), all isolates yielded amplified products of 1,018bp. Of the 150 isolates of Pseudomonas spp., a bacterial strain P. putida P84 isolated from tomato rhizosphere showed to suppress a wide range of phytopathogenic bacteria in vitro. The best source of carbon for P84 strain were glucose, arabinose, inositol and melibiose. In greenhouse experiments, P84 strain suppressed the development of bacterial wilt in tomato with a control value of 60%.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.216-222
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• 2010

This study was carried out to determine the effects of olive oil prepared tomato powder (OPTP) used as lycopene source on fresh pork patties. OPTP was not added (0%; C), or was added at 0.25% (T1), 0.5% (T2), 0.75% (T3) and 1.0% (T4) in a basic pork patty formula and patties were stored for 7 days at $5^{\circ}C$. pH values of T3 and T4 were lower (p<0.05) than those of control until storage day 3. However, pH values of treated samples were dramatically increased (p<0.05) after 7 d of storage. Cooking loss values of treatments were lower (p<0.05) than those of control at day 1 of storage. Thiobarbituric acid reacting substances values were lower (p<0.05) in all treatments than in untreated samples during storage. All treated samples had lower values (p<0.05) for lightness ($L^*$) but significantly higher values (p<0.05) for redness ($a^*$) and yellowness ($b^*$) than the untreated samples during storage. Total plate counts of T4 were lower (p<0.05) than others during storage. In sensory evaluation, the scores of color, aroma and overall acceptability in T3 and T4 scored higher (p<0.05) than those of control at days 1 and 3 of storage, however, statistical significance was not found (p>0.05) among the samples after 7 days of storage. In conclusion, tomato powder-treated groups were significantly higher in redness ($a^*$) and yellowness ($b^*$), and lipid oxidation was inhibited, as compared with control during storage. Therefore, as a natural additive, tomato powder could be used to extend the self-life of meat products, providing the consumer with food containing natural additives, which might be seen more healthful than those of synthetic origin.

• Research in Plant Disease
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• v.18 no.4
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• pp.298-303
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• 2012

Tomato yellow leaf curl virus (TYLCV), transmitted exclusively by the whitefly (Bemisia tabaci) in a circulative manner is one of the most important virus in tomato. Since the first report of TYLCV incidence in Korea in 2008, the virus has rapidly spread nationwide. TYLCV currently causes serious economic losses in tomato production in Korea. Early detection of TYLCV is one of the most important methods to allow rouging of infected tomato plants to minimize the spread of TYLCV disease. We have developed an ultra-rapid and sensitive real-time polymerase chain reaction (PCR) using a new designed real-time PCR system, GenSpectorTM TMC-1000 that is a small and portable real-time PCR machine requiring only a $5{\mu}l$ reaction volume on microchips. The new system provides ultra-high speed reaction (30 cycles in less than 15 minutes) and melting curve analysis for amplified TYLCV products. These results suggest that the short reaction time and ultra sensitivity of the GenSpector$^{TM}$-based real-time PCR technique is suitable for monitoring epidemics and pre-pandemic TYLCV disease. This is the first report for plant virus detection using an ultra-rapid real-time PCR system.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2007.11a
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• pp.162.2-162.2
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• 2007