Antagonistic and antioxidant effect of probiotic Weissella cibaria JW15

Food Science and Biotechnology - The objective of this study was to evaluate the functional properties of Weissella cibaria JW15 (JW15) by investigating its antagonistic and antioxidant activities....     

Evaluation of the transfer rate of ochratoxin a to decoctions of herbal medicines

Ochratoxin A (OTA), a mycotoxin classified as a potentially carcinogenic to humans, is slightly soluble in water. In this study, the transfer rate of OTA in herbal medicines to decoctions was investigated. Herbal medicine decoctions were prepared by boiling and autoclaving herbal medicines contaminated with OTA after soaking and not soaking in water. OTA amounts in decoctions and residues were analyzed using HPLC. Transfer of OTA (12.72–61.33%) from herbal medicines to decoctions was observed. Soaking and autoclaving steps enhanced the transfer rate of OTA to decoctions. The results meant that there is a potential risk for consumption of herbal medicine decoctions. Therefore, regular monitoring for mycotoxins, including OTA, in herbal medicines and proper management to ensure the safety of herbal medicines is necessary to protect consumers.     

Mission Analysis and Planning System for Korea Multipurpose Satellite-I

The Mission Analysis and Planning System (MAPS) has been developed for a low earth orbiting remote sensing satellite, Korea Multipurpose Satellite-I (KOMPSAT-I), to monitor and control the orbit and the attitude as well as to generate mission timelines and command plans. The MAPS has been designed using a top-down approach and modular programming method to ensure flexibility in modification and expansion of the system. Furthermore, a graphical user interface has been adopted to ensure user friendliness. Design, implementation, and testing of the KOMPSAT MAPS is discussed in this paper.     

A new method of ozone forecasting using fuzzy expert and neural network systems

This study describes the method of forecasting daily maximum ozone concentrations at four monitoring sites in Seoul, Korea. The forecasting tools developed are fuzzy expert and neural network systems. The hourly data for air pollutants and meteorological variables, obtained both at the surface and at the high elevation (500 hPa) stations of Seoul City for the period of 1989-1999, were analyzed. Two types of forecast models are developed. The first model, Part I, uses a fuzzy expert system and forecasts the possibility of high ozone levels (equal to or above 80 ppb) occurring on the next day. The second model, Part II, uses a neural network system to forecast the daily maximum concentration of ozone on the following day. The forecasting system includes a correction function so that the existing model can be updated whenever a new ozone episode appears. The accuracy of the forecasting system has been improved continuously through verification and augmentation.     

Production of Coturnix quail immunoglobulins Y (IgYs) against Vibrio parahaemolyticus and Vibrio vulnificus

Production of chicken immunoglobulins Y (IgYs) and their applications in prophylactic, therapeutic, detection of microbial contaminants and as a diagnostic tool has been widely studied with limited information from other avians. This study produced Coturnix quail (Coturnix coturnix japonica) egg yolk IgYs against Vibrio parahaemolyticus and Vibrio vulnificus. Formalin inactivated (FIVP, FIVV, mixed FI-VP/VV) and heat inactivated (HIVP, HIVV, mixed HI-VP/VV) Vibrio immunogens (10⁹ CFU/mL) were intramuscularly immunized into quail through thigh muscles. Egg yolk IgY was purified by water dilution-ammonium sulfate precipitation method and the activity was determined by enzyme-linked immunosorbent assay (ELISA). Formalin inactivated immunogens induced high humoral immune response for both V. parahaemolyticus and V. vulnificus over heat inactivated immunogens. However, IgYs resulted from HIVP and FIVV immunogens, showed high specificity to V. parahaemolyticus and V. vulnificus respectively. Detection limits of the indirect ELISA using the produced IgYs were 10⁵ CFU/mL for V. parahaemolyticus and 10⁶ CFU/mL for V. vulnificus. The developed antibodies showed high binding affinity to their corresponding immunogens, very little cross reactivity to Staphylococcus aureus and not other bacteria strains (p<0.05), a phenomenon which was also observed in Western blot.     

Determination of matrix effects occurred during the analysis of organochlorine pesticides in agricultural products using GC-ECD

Matrix effects observed during the multiresidue analysis of seven organochlorine pesticides in six different agricultural products with GC-ECD were assessed. The presence of matrix coextractives, a major cause of observed matrix effects, directly and/or indirectly influenced the chromatographic responses of some pesticides. Two types of external calibrations, solvent calibration (SC) and matrixmatched calibration (MC), were used to assess matrix effects. Greater matrix effects were observed at the lower concentrations of each pesticide. The extent of matrix effects varied unpredictably with matrix type. Among the analyzed pesticides, iprodione, cyhalothrin, and cypermethrin exhibited greater matrix effects (>150%) for almost all matrices. The pesticide recovery rates obtained with MC were not statistically different from a 100% recovery rate in most samples, which indicates that MC may diminish the overestimates occurred due to matrix effects in GC analysis.     

Changes in thermoluminescence properties of minerals separated from irradiated potatoes and garlic during long-term storage under different light conditions

The effect of different light conditions on the specificity and reliability of thermoluminescence (TL) analysis to detect irradiated samples (potatoes and garlic) during 2?years of storage was investigated. The silicate minerals separated from the nonirradiated samples provided a low-intensity TL glow curve with a maximum peak after 300?°C demonstrating the absence of an irradiation history. The TL glow curve from the irradiated samples provided easy discrimination with TL glow curves of high intensity and maximum peak in temperatures range of 160?C185?°C. The results were also confirmed by calculating the TL ratio (TL₁/TL₂) through normalization (re-irradiation) step. The key parameters of the TL analysis including the TL intensity, TL glow curve shape, and the TL ratio exhibited a time-dependent change. The bleaching effect of different light conditions was also significant, which was most prominent in the case of natural light with a prominent decrease in the TL intensity and ratio. The maximum TL glow peak also showed a shift towards the higher temperature. However, all irradiated samples, irrespective of the storage conditions and time, were easily discernable from the nonirradiated ones considering the shape and intensity of the TL glow curve.     

Micronization of cilostazol using supercritical antisolvent (SAS) process: Effect of process parameters

The aim of this study was to improve dissolution rate of poorly water-soluble drug, cilostazol, using supercritical antisolvent (SAS) process. The effect of process variables, such as pressure, temperature, drug concentration, type of solvents, feed rate ratio of CO₂/drug solution, on drug particle formation during SAS process was investigated. Particles with mean particle size ranging between 0.90 and 4.52 μm were obtained by varying process parameters such as precipitation vessel pressure and temperature, drug solution concentration, solvent type, feed rate ratio of CO₂/drug solution. In particular, mean particle size and distribution were markedly influenced by drug solution concentration during SAS process. Moreover, the drug did not change its crystal form and the operating parameters might control the ‘crystal texture’ due to the change in crystallinity and preferred orientation during SAS process, as confirmed by differential scanning calorimetry and powder X-ray diffraction study. In addition, the dissolution rate of drug precipitated using SAS process was highly increased in comparison with unprocessed drug. Therefore, it is concluded that the dissolution rate of drug is significantly increased by micronization of cilostazol, leading to the reduction in particle size and increased specific surface area after SAS process.