• Toxicological Research
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• v.24 no.1
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• pp.87-91
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• 2008

The present study was conducted to monitor the level of triflumizole residues in fruits (apple and pear) and vegetable (cucumber) samples in order to assess risk posed by the presence of such residues to the consumer. Triflumizole was applied at a recommended dose rate to apple and pear pulps and to a cucumber sample. The samples were collected at harvesting time following several treatments (three and/or four treatments). Triflumizole was extracted with methanol and re-extracted into dichloromethane. The presence of triflumizole was determined by HPLC with UV detection at 238 nm following the cleanup of the extract by open preparative chromatographic column with Florisil. The versatility of this method was evidenced by its excellent linearity (> 0.999) in the concentration range between 0.2 and 4.0 mg/kg. The mean recoveries evaluated from the untreated samples spiked at two different fortification levels. 0.1 and 0.4 mg/kg, and ranged from 87.5${\pm}$0.0 to 93.3${\pm}$2.6 for the tested fruits and vegetable, respectively, and the repeatability (as relative standard deviation) from three repetitive determinations of recoveries were no larger than 6%. The calculated limit of detection was 0.02 mg/kg and the minimum detectable level of 4 ng for triflumizole was easily detected. When triflumizole was sprayed onto the apple trees three times at 50-40-30 and 40-30-21 days prior to harvesting and four times onto the pear trees at 40-30-21-14 days prior to harvesting, the mean residual amounts of 0.05 and 0.06 mg/kg for apples and pears, respectively, were not detected in all of the treatments. When the cucumber sample was fumigated four times at 7, 5, 3 and 1 day prior to harvesting, the mean residual amount was not detectable. Triflumizole can be used safely when sprayed (wettable powder, 30% active ingredient) and fumigated (10%) 4 times at 14 and 1 day prior to harvesting to protect the fruits and vegetable, respectively.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.149-159
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• 2011

Bentazone is benzothiadiazole group herbicide, and used to foliage treatment. This herbicide have already been widely used for cereals and vegetables planting in worldwide. This experiment was conducted to establish a determination method for bentazone residue in crops using HPLC-UVD/MS. Bentazone residue was extracted with acetone (adjusted pH 1 with phosphoric acid) from representative samples of five raw products which comprised hulled rice, soybean, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and dichloromethane partition was followed to recover bentazone from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The bentazone was quantitated by HPLC with UVD, using a YMC ODS AM 303 ($4.6{\times}250$ mm) column. The crops were fortified with bentazone at 3 levels per crop. Mean recovery ratio were ranged from 82.0% for a 0.2 mg/kg in apple to 97.9% for a 0.02 mg/kg in Chinese cabbage. The coefficients of variation were ranged from 0.5% for a 0.02 mg/kg in soybean to 9.7% for a 0.02 mg/kg in Chinese cabbage. Quantitative limit of bentazone was 0.02 mg/kg in representative five crop samples. A LC/MS with selected-ion monitoring was also provided to confirm the suspected residue. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of bentazone in agricultural commodities.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1465-1470
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• 1999

Aroma was extracted from Applemint(Mentha rotundifolia(L.) Huds) with SDE(simultaneous distillation and extraction), SFE(supercritical fluid extraction) and headspace method and the compounds of aroma were tentatively identified with GC-MS. The functionality of aroma compounds were determined with GC-olfactometry. Total 67 compounds were identified. Among them, 39 compounds were determined from SDE, 42 from SFE and 16 from headspace extract. Many terpene compounds were extracted with SDE and headspace methods but hydrocarbones with SFE. The major constituents of aroma obtained from SDE and SFE, were piperitenone oxide, germacrene-D and trans sabinene hydrate, but those from headspace method were 3-octanol, 1,8-cineol, camphene and benzeneacetaldehyde. Results of sniffing test, determining characteristics and strength of aroma showed that the major constituents of SDE extract were refreshing sweet and apple-like(ethyl-2-methyl butanoate), sweet and fruity-like$({\alpha}-thujene)$, fresh mushroom-like(1-octen-3-ol, 3-octanol), and bitter herb-like$({\delta}-cadidene)$. Major constituents of aroma extracts obtained from headspace method were alcoholic, refreshing sweet and apple-like(ethyl 2-methyl butanoate), unpleasant chemical, and bitter herb and grassy-like(camphene).

• Korean Journal of Organic Agriculture
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• v.5 no.2
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• pp.117-128
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• 1997

This study was carried out to investigate the amounts of voluntary intake, digestibility and nitrogen retention in Korean native goats (KNG) fed agricultural by-products containing rice straw (RS) and apple pomace (AP) and to obtain a basic information for establishing the feeding system of KNG. The result are as follows. 1. Among the chemical composition of experimental diets, the highest values in crude protein (CP ; 18.6%) and crude ash contents (10.7%) were observed in alfalfa hay. Those of RS+AP treatment were significantly low 6.0 and 4.8%, respecitively. Acid detergent fiber (ADF), ether extract and non-structural carbohydrate (NSC) contents were shown an adverse tendency. 2. Dry matter (DM) intakes per day in KNG fed RS+commercial diet (CD), RS+AP and RS+AP+CD were significantly lower (P<0.05) 210.3, 228.3, respectively than 358.1g in alfalfa hay. 3. DM intakes per basal weight expressed as DM g/kg of BW0.75 and DM g/kg of BW(%) were highest (P<0.05) 60.5g and 3.3%, respectively in KNG fed alfalfa hay, any other treatments showed 35.6 to 42.5g and 2.0 to 2.3%, respectively and this result was similar to those of DM intake per day. 4. Digestibilities of DM, organic matter, CP, ADF, neutral detergent fiber (NDF). crude ash and ether extract in alfalfa hay and RS+AP+CD treatment were significantly higher (P<0.05) than RS+CD treatment. Those of CP, ADF and NDF of RS+AP treatment in not significantly different with these treatments. 5. NSC digestibility was higher in alfalfa hay (66.7%) than those of other treatments (44.2~52.0% ; P<0.05). 6. Nitrogen retentions expressed as N retention(g) and N retention (%) in KNG were highest (P<0.05) 0.6g and 15.6%, respectively in RS+AP+CD treatment and RS+CD treatment was lowest (P<0.05) -06g and -21.4%, respectively.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.73-74
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• 2024

To control western flower thrips (Frankliniella occidentalis), a significant pest of peppers, the control effects of eco-friendly agricultural materials were tested when treated alone and in combination. The control effects of yellow sticky roll traps installed on the stem, predatory natural enemy (Hypoaspis miles) inoculated on the stem, and plant extracts (50% custard apple seed oil + 10% cinnamon extract) sprayed on the foliage were 45.3%, 36.6%, and 50.2%, respectively, when treated individually. Meanwhile, when three eco-friendly agricultural materials were comprehensively applied, the control effect was maintained between 62.4% and 80.9% compared to untreated conditions during the pepper harvesting season. These methods can be utilized for the eco-friendly control of western flower thrips in pepper greenhouses.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.352-355
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• 2000

Production of pullulan by Aureobasidium pullulans HP-2001 with agro-industrial byproducts was investigated. Agro-industrial byproducts from the rice processing industry for the traditional Korean food (AIB-A), apple juice production (AIB-B), and soybean sauce production (AIB-C) were used for carbon and nitrogen source for production of pullulan. Major components of AIB-A were glucose, maltose, maltotriose, and dextran. AIB-A and B were found to be good substitute to glucose as carbon source. Productivity of pullulan with AIB-A and B as carbon source was similar to that glucose. Molecular weight of pullulan produced with AIB-A and B was higher than that with glucose. Major components of AIB-B and C were carbohydrate, protein, fat and ash. AIB-C was also a good substitute to yeast extract as nitrogen source. Some of physiological conditions were examined for the large scale production of pullulan.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.280-285
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• 2010

In the course of a searching natural antifungal compounds from plant sources, we found that the methanol extract ($3,000\;{\mu}g/ml$) of Malus domestica fruits had potential of control against rice blast (Magnaporthe grisea) and tomato late blight (Phytophthora infestans). Under bioassay-guided purification, we isolated phloretin, a phenolic compound, with in vivo antifungal activity against M. grisea. By 1-day protective application of phloretin ($500\;{\mu}g/ml$), the compound strongly inhibited the disease development of M. grisea and P. infestans on rice and tomato seedlings, respectively. And red pepper anthracnose caused by Colletotrichum coccodes also was moderately suppressed. However, rice sheath blight (Rhizoctonia solani AG1), and barley powdery mildew (Blumeria graminis f. sp. hordei) were hardly controlled. In addition, the compound showed in vitro antifungal activity against some plant pathogenic fungi including Phytophthora capsici, Alternaria panax, Sclerotinia sclerotiorum, R. solani AG4, and M. grisea. This is the first report on the antifungal activity of phloretin against plant pathogenic fungi.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.247-256
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• 2010

A high-performance liquid chromatographic (HPLC) method was developed to determine buprofezin residues in hulled rice and fruits. The buprofezin residue was extracted with acetone and the extract was stepwise purified by liquid-liquid partition and Florisil column chromatography. For rice samples, acetonitrile/n-hexane partition was additionally employed to remove nonpolar lipids. Reversed phase HPLC using an octadecylsilyl column was successfully applied to separate buprofezin from sample co-extractives, as detected by ultraviolet absorption at 250 nm. Recovery experiment at the limit of quantitation validated that the proposed method could evidently determine the buprofezin residue at the level of 0.02 mg/kg. Mean recoveries from hulled rice, apple, pear, and persimmon samples fortified at three tenfold levels were in the range of 80.8~85.2%, 89.1~98.4%, 88.8~95.7% and 90.8~96.2%, respectively. Relative standard deviations of the analytical method were all less than 5%, irrespective of sample types. A selected-ion monitoring LC/mass spectrometry with positive electrospray ionization was also provided to sensitively confirm the suspected residue.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.109-116
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• 2018

Onion vinegar, which has an undesirable flavor and taste formed through alcohol and acetic acid fermentation, possesses additives that can improve sensory quality. Thus, the objective of this study was to present an optimized blending ratio using response surface methods for an onion vinegar beverage by adding Omija extracts. This study was performed to formulate an Omija-onion vinegar beverage (OOVB) and investigate its antioxidant properties and antimicrobiological effects. The experimental design was conducted using an optimal mixture model of response surface methodology which generated eighteen experimental trials with overall acceptance as the responses. According to the statistical analyses, OOVB demonstrated a ratio containing onion vinegar, water, brown sugar, apple extracts and Omija extracts of 10, 72.3, 4.4, 12.2 and 1.1 (weight ratio), respectively. The OOVB revealed desirable nutrition values (phenolics compounds 19.3 mg/100 g, total flavonoids 3.1 mg/100 g, quercetin 1.9 mg/100). The OOVB displayed antibacterial effects in Gram negative Enterobacter aerogenes, Escherichia coli, Salmonella typhimurium and Gram positive Staphylococcus aureus. The findings revealed that OOVB was 18% in DPPH radical inhibitionand 11% in superoxide dismutase-like activity thus, OOVB has nutritional value and good quality as well as potential biological activities for functional beverages.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.41-41
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• 2011

The aims of this study were to examine the efficacy of phytochemicals of Rumex crispus as anti-oxidant and anti-browning agent. The bioactive properties of Rumex crispus as natural colorants were studied by total phenolic contents, DPPH radical scavenging, ABTS radical scavenging,lipid peroxidation, cell viability, singlet oxygen quenching and photoprotection effect. Among all of the results ($IC_{50}$: the concentration of various extracts required to exert 50% reducing effect), the higher activity of the extract was found in the ethyl acetate and butanol extracts. Anti-browning activity was evaluated by monitoring the change $L^*$, $a^*$, $b^*$ values and total color differences(${\Delta}E$). It was found that ethyl acetate and butanol extracts effectively inhibited browning in apple juice at a concentration below 0.3 mg/ml. Rumex crispus extracts used natural colorants could be of good resources as anti-oxidant and anti-browning agents. The results suggest that our study may contribute to the development of natural and functional materials with potential application to reduce oxidative damage.