• Korean Journal of Food Science and Technology
• /
• v.24 no.3
• /
• pp.193-198
• /
• 1992

The inhibitory effects of radish juice on the mutagenicities of cigarette smoke condensate (CSC), methanol extract of charred part of fried or broiled saury pike (MECS) and 2-aminofluorene (2-AF) were examined by the use of Ames assay toward Salmonella typhimurium TA 98 strain. Radish juice exhibited inhibition percentage of about 100, 100 and 87 on the mutagenicities of CSC, two kinds of MECS and 2-AF, respectively. Except for juices of cabbage and leek, radish juice has inhibited more effectively the mutagenicity of CSC than other fruit or vegetable juices studied. Inhibitory effect of radish juice might be originated from the components with molecular weight above 50,000 and decreased sharply in 5 min by heat treatment at $100^{\circ}C$, but hardly changed at low and moderate storage temperatures such as $4^{\circ}C,\;10^{\circ}C,\;25^{\circ}C\;and\;35^{\circ}C$ for about 2 weeks. Precipitate obtained from ammonium sulfate saturation from 30 to 80% had inhibitory effect on the mutagenicity of CSC. Extracts from 3 bands of non-denaturing gel of $30{\sim}80%$ amnonium sulfate precipitate have exhibited the inhibitory effects on the mutagenicity of CSC.

• KSBB Journal
• /
• v.19 no.6 s.89
• /
• pp.427-432
• /
• 2004

The purpose of this study is to investigate the feasibility of a cosolvent-modified supercritical $CO_2\;(scCO_2)$ extraction technique for the production of licorice extracts with high levels of glabridin. The effects of various parameters such as the type and amount of modifiers, extraction temperature ($40{\sim}80^{\circ}C$) and pressure ($10{\sim}50.0\;MPa$) on the extraction efficiency were examined at a fixed flow rate of 1 mL/min. The organic solvent extraction with pure methanol was also conducted for a quantitative comparison with the $scCO_2$ extraction. The recovery of glabridin from licorice was found to be extremely small for pure $scCO_2$. However, the addition of modifiers such as ethanol and acetone to $scCO_2$ resulted in a significant improvement in the recovery of glabridin. The recovery of glabridin was observed to increase with pressure at a constant temperature. Furthermore, the purity of the glabridin obtained from the $scCO_2$ extraction was higher compared with the organic solvent extraction.

• Journal of Life Science
• /
• v.23 no.5
• /
• pp.629-636
• /
• 2013

This study was performed to evaluate the anti-inflammatory and antioxidant activities of methanol extract from the leaves of Picrasma quassioides BENNET (PLME). The antioxidant effects of PLME were measured based on polyphenol and flavonoid contents. PLME was found to have $367.52{\mu}g/mg$ and $46.61{\mu}g/mg$ high polyphenol and flavonoid contents. Cell viability was determined by MTT assay. The production of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) was measured by Griess assay and enzyme-linked immunosorbent assay (ELISA). In order to effectively anti-inflammatory agents, we examined the inhibitory effects on the production of lipopolysaccharide (LPS)-induced NO and $PGE_2$ in RAW 264.7 cells. PLME significantly decreased the production of NO and $PGE_2$ in a dose-dependent manner, and also reduced the expression of iNOS, a COX-2 protein. In addition, PLME reduced the NF-${\kappa}B$, $I{\kappa}B$ phosphorylation in RAW 264.7 cells upon stimulation with LPS (100 ng/ml) for 24 h. These results provide evidence for the anti-inflammatory and antioxidant effects of Picrasma quassioides leaves.

• Journal of Food Hygiene and Safety
• /
• v.34 no.3
• /
• pp.227-234
• /
• 2019

An analytical method was developed for the determination of oxytetracycline in agricultural products using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method by liquid chromatography-tandem mass spectrometry (LC-MS/MS). After the samples were extracted with methanol, the extracts were adjusted to pH 4 by formic acid and sodium chloride was added to remove water. Dispersive solid phase extraction (d-SPE) cleanup was carried out using $MgSO_4$ (anhydrous magnesium sulfate), PSA (primary secondary amine), $C_{18}$ (octadecyl) and GCB (graphitized carbon black). The analytes were quantified and confirmed with LC-MS/MS using ESI (electrospray ionization) in positive ion MRM (multiple reaction monitoring) mode. The matrix-matched calibration curves were constructed using six levels ($0.001{\sim}0.25{\mu}g/mL$) and coefficient of determination ($r^2$) was above 0.99. Recovery results at three concentrations (LOQ, $10{\times}LOQ$, and $50{\times}LOQ$, n=5) were from 80.0 to 108.2% with relative standard deviations (RSDs) less than of 11.4%. For inter-laboratory validation, the average recovery was in the range of 83.5~103.2% and the coefficient of variation (CV) was below 14.1%. All results satisfied the criteria ranges requested in the Codex guidelines (CAC/GL 40-1993, 2003) and the Food Safety Evaluation Department guidelines (2016). The proposed analytical method was accurate, effective and sensitive for oxytetracycline determination in agricultural commodities. This study could be useful for safety management of oxytetracycline residues in agricultural products.