• Korean Journal of Food Science and Technology
• /
• v.36 no.1
• /
• pp.14-18
• /
• 2004

Analysis methods of artificial sweeteners, aspartame, acesulfame potassium, sodium saccharin, and sucralose isolated from foods were developed using high performance liquid chromatography, HPLC conditions for aspartame, acesulfame potassium, and sodium saccharin were: column, Symmetry $C_{18}(3.9mm\;i.d{\times}150mm,\;5{\mu}m)$; mobile phase, 0.05M sodium phosphate monobasic : acetonitrile (9 : 1, pH 3.5, containing 0.01M tetrapropylammonium hydroxide); detector, UV detector at 210 nm. HPLC condition for sucralose were : column, Symmetry $C_{18}(3.9mm\;i.d{\times}150mm,\;5{\mu}m)$; mobile phase, water:methanol (7 : 3); detector, refractive index detection (sensitivity = 16). Recoveries of artificial sweeteners in foods including soft drinks, fruit and vegetable beverages, alcoholic beverages, fermented milk beverages, soybean milk, ice cream, snacks, chewing gums, jam, honey, kimchi salted food, special dietary products, processed fish products, candies, food additive mixtures, chocolate and cocoa were 76.1-101.3%, 82.3-103.2%, 83.1-103.7%, and 80,6-99.5% for aspartame, acesulfame potassium, sodium saccharin, and sucralose, respectively.

• The Korean Journal of Pesticide Science
• /
• v.21 no.1
• /
• pp.49-61
• /
• 2017

The study was conducted for safety evaluation of 208 kinds of residue pesticides on 200 dried agricultural products, which are distributed in Gwangju. The method of monitoring was the second of Multi Class Pesticide Multi-residue Methods in Korean Food Code, and GC-ECD, GC-NPD, GC-MSD, and LC-MS/MS were used as evaluation equipment to analyze. The residue level in pesticides were 15.5% (31 of 200 samples) and 4 samples exceeded MRLs. 4.5 mg/kg of pyraclostrobin (MRL; 3.0 mg/kg) was detected in red pepper, 1.49 mg/kg of chlorpyrifos (MRL; 0.13 mg/kg) in daikon leaves, 38.26 mg/kg of pyridalyl (MRL; 0.25 mg/kg) in pepper leaves, 0.98 mg/kg of chlorpyrifos (MRL; 0.05 mg/kg), respectively. Pesticides were found on the 15 samples among the 21 samples of red pepper which is a fruit vegetable, and this resulted in high detection rate of 71%. In addition, pesticides were detected on chwinamul, shitake, siler divaricata, daikon leaves and others within MRLs. The frequent detected kinds of pesticides were insecticide (47.6%), fungicide (33.3%), acaricide (14.3%), nematicide (4.8%) in the order named, and pesticides were methoxyfenozide > pyraclostrobin > azoxystrobin, chlorantraniprole > novaluron, trifloxystrobin in frequent order.

• Journal of Food Hygiene and Safety
• /
• v.34 no.5
• /
• pp.413-420
• /
• 2019

In this study, a sample preparation method and a simultaneous determination method by ultra-high performance liquid chromatography coupled with tandem mass spectrometry for 9 isomers of chlorogenic acid and arbutin in fruits were developed. The samples were extracted using 90% methanol (pH 3.0), with the solutions being shaken and then sonicated for 10 min each. After centrifugation at 4,000 rpm for 10 min, the extraction was concentrated under a vacuum at $40^{\circ}C$ using a vacuum evaporator. The residue was dissolved in 5 mL of 5% methanol and filtered through a $0.45{\mu}m$ membrane before UHPLC-MS/MS analysis. The separations were performed on a C18 column with gradient elution of water (containing 0.1% formic acid) and methanol (containing 0.1% formic acid). The specificity, linearity, limit of detection, limit of quantification, accuracy, and precision of the proposed methods were also evaluated.

• Journal of Plant Biotechnology
• /
• v.46 no.3
• /
• pp.228-235
• /
• 2019

Apple (Malus pumila) is one of the most economically important fruits in Korea. but virus infection has decreased the sustainable production of apples and caused serious problems such as yield loss and poor fruit quality. Virus or viroid infection including apple chlorotic leaf spot virus (ACLSV), apple stem pitting virus (ASPV), apple stem grooving virus (ASGV), apple mosaic virus (ApMV) and apple scar skin viroid (ASSVd) have been also reported in Korea. In many cases, as apple gets infected with virus and viroid with no specific symptoms, the damage and symptoms caused by the viruses are not detected. In our research, viruses in the rootstock were eliminated for a virus-free apple dwarfing rootstock of M.9 and M.26. The virus elimination methods were apical meristem culture, thermotherapy ($37^{\circ}C$, 6 weeks) and chemotherapy($Ribavirin^{(R)}$). The detection of apple viruses was accomplished by Enzyme-linked Immuno-Sorbent Assay (ELlSA) and reverse transcription-polymerase chain reaction (RT-PCR). RT- PCR method was 10 ~ 30% more sensitive than the ELISA method. The efficiency of virus elimination was enhanced in apical meristem culture method. The acquisition rate of virus-free apple dwarfing rootstocks was 30 ~ 40% higher in apical meristem culture. After the meristem culturing of M.9, the infection ratio of ACLSV, ASPV and ASGV was 45%, 60% and 50%, respectively. In the apple dwarfing rootstock of M.26, the infection ratio of ACLSV, ASPV and ASGV was 40%, 55% and 55%, respectively. Based on this study, the best method for the production of virus-free apple dwarfing rootstocks was the apical meristem culture.