Earticle

Total phenolics and antioxidant properties of various Korean commercial vinegars (apple vinegar, AV; blueberry vinegar, BV; grape vinegar, GV; lemon vinegar, LV; Opuntia ficus vinegar, OFV; persimmon vinegar, PV; Prunus mume vinegar, PMV; rice vinegar, RV) were investigated. The total phenolic contents of 8 vinegars were within the range of 54.18- 491.02 μg/mL. The vinegars were also capable of scavenging 1,1-dipehnyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-3- ethylbenzothiazoline-6-sulphonic acid (ABTS) radicals in a manner dependent on concentration. The greatest reducing power was observed in PV relative to the other vinegars. The ferric reducing ability of plasma (FRAP) of PV, PMV, GV, and BV were 1.012, 0.969, 0.931, and 0.856 at a dose of 1 mL, respectively. Therefore, our study verified that the GV, PV, and PMV have powerful antioxidant activities which are correlated with its high level of phenolics, particularly gallic acid, and epigallocatechin.

Danshen (Salvia miltiorrhiza Bunge) is a traditional Korean medicine that is commonly used for the treatment of inflammatory diseases such as edema, arthritis, hepatitis, and endangitis. The several extracts of danshen were tested for antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA) isolated in clinic by broth microdilution method, the checkerboard, and time-kill methods to evaluate the synergistic effects of the combination of the extracts with antibiotics. The chloroform (CHCl3) and n-hexane (HEX) extracts [minimum inhibitory concentration (MIC), 0.0078- 0.3125 μg/mL; minimum bactericidal concentration (MBC), 0.019-0.625 μg/mL] were found to have strong antibacterial activity against MRSA. Additionally, when the CHCl3 and HEX extracts were co-administered with ampicillin or oxacillin, a synergistic effect against MRSA was observed. Furthermore, a time-kill study evaluating the effects of the extracts against MRSA indicated that treatment with the CHCl3 extract in combination with ampicillin or oxacillin produced rapid bactericidal activity. These results suggest that danshen extracts may have potently antimicrobial activity and thus, it can be a suitable phytotherapeutic agent for treating MRSA infections.

This study aimed to evaluate the potential allergenicity of Cry proteins in insect-resistant genetically modified (GM) maizes (Bt11, MON810, and MON863) using serum screening tests. Serum samples were obtained from Korean children (0-15 years old) with allergic symptoms who had positive maize-specific IgE. The levels of serum specific IgE was measured by the Phadia ImmunoCAP system and considered as positive when they are 0.35 kU/L or higher. Cry proteins (Cry1Ab in Bt11, mCry1Ab in MON810, and Cry3Bb1 in MON863) were expressed in Escherichia coli and purified for serum screening. The reactivity of purified Cry proteins was confirmed by IgE immunoblots in 50 patients (maize-sensitized patients). There was no reaction between Cry proteins and sera from maize-sensitized patients. Our results suggest that these Cry proteins are not likely to cause allergic reactions. Further studies using more sera from patients with true clinical allergies are needed to evaluate the potential allergenicity of novel proteins in GM maize.

Garlic has been used for condiments and also for medicines to cure various diseases since ancient times. Many studies on the processing of garlic have been published, however, few of them were related with fermentation because of the antimicrobial action of the garlic. In this study, to conduct garlic fermentation, 4 lactic acid bacteria (LAB) strains with growth abilities in garlic medium were selected. Addition of various nitrogen, carbon, and mineral sources generally did not improve the growth of experimental strains during garlic fermentation except for Lactobacillus casei KFRI 704 by yeast extract and Lactococcus lactis subsp. cremoris ATCC 19257 by mineral sources. High performance liquid chromatography (HPLC) analysis of 32 phenolic compounds during fermentation showed that formononetin was decreased time dependently. The concentrations of volatile compounds and alliin did not change during fermentation. The results of this study would provide the basic understanding of garlic fermentation by selected strains of LAB.

Tumor necrosis factor (TNF)-α is chronically elevated in adipose tissues of obese rodents and humans. Increased levels of TNF-α have been implicated in both the induction of atherogenic adipokines, such as plasminogen activator inhibitor (PAI)-1, and the inhibition of the anti-atherogenic adipokine, adiponectin. In this study, we investigated the effects of transstilbene, piceatannol, rhaponticin, and piceid on the TNF-α-induced atherogenic changes of adipokines in 3T3-L1 cells. Exposure to TNF-α for 24 hr increased PAI-1 secretion and decreased adiponectin secretion. Among stilbenoids, piceatannol significantly inhibited the increased secretion of PAI-1 induced by TNF-α. Adiponectin secretion decreased by TNF-α was recovered after trans-stilbene and rhaponticin treatments. Our results showed that stilbenoids exerted different effects on TNF- α-induced changes in adipokines secretion in 3T3-L1 adipocytes according to their structural characteristics.

Volatile flavor compounds were isolated from the flowers of Chrysanthemum indicum L. (gamguk) produced in Korea and China by the hydro distillation, and were analyzed by gas chromatography-mass spectrometry (GC/MS). The yield of oils from Korean and Chinese gamguk were 2.0 and 0.5%(v/w), respectively. Sixty-three volatile compounds of Korean gamguk representing 89.28% of the total peak area were tentatively identified, including 35 hydrocarbons, 12 alcohols, 6 ketones, 3 esters, 5 aldehydes, 1 oxide, and 1 miscellaneous component. Thirty-six volatile components of Chinese gamguk constituted 58.15% of the total volatile composition were tentatively characterized, consisting of 19 hydrocarbons, 7 alcohols, 2 ketones, 2 esters, 4 aldehydes, 1 oxide, and 1 miscellaneous component. The predominant components of Korean oil were α-pinene, 1,8-cineol, and chrysanthenone. Whereas, camphor, α-curcumene, and β-sesquiphellandrene were the main aroma compounds of Chinese gamguk.

In this study, drying kinetics of onion slices was examined in a laboratory scale vacuum dryer at an air temperature in a range of 50-70oC. Moisture transfer from onion slices was described by applying the Fick’s diffusion model, and the effective diffusivity was calculated. Temperature dependency of the effective diffusivity during drying process obeyed the Arrhenius relationship. Effective diffusivity increased with increasing temperature and the activation energy for the onion slices was estimated to be 16.92 kJ/mol. The experimental drying data were used to fit 9 drying models, and drying rate constants and coefficients of models tested were determined by non-linear regression analysis. Estimations by the Page and Two-term exponential models were in good agreement with the experimental data obtained.

To develop a dietary beverage with functionalities of cheonggukjang, soymilk was fermented with Bacillus subtilis and its antioxidant activities were examined. Antioxidative capacities of fermented soymilk (FS) with 5 different B. subtilis were significantly different. Among these, FS with 2829PNU015 revealed the greatest antioxidant activities. 1,1-Diphenyl-2- picrylhydrazyl (DPPH) scavenging activity, total antioxidant activity, and low density lipoprotein (LDL) oxidation inhibition of FS with 2829PNU015 were increased by 150, 140, and 240%, respectively, compared with those of unfermented soymilk (p<0.05). Further study for the improvement of sensory properties of FS with B. subtilis is required for a commercial production.

Macelignan is a bioactive compound isolated from nutmeg (Myristica fragrans Houtt.) which has been traditionally used for the food and pharmaceutical purposes. In this study, the activities of macelignan against vegetative cells and spores of Bacillus cereus were evaluated in vitro. Our results showed that the vegetative cells of B. cereus were significantly inhibited in growth by macelignan with minimum inhibitory concentration (MIC) of 4 μg/mL. The vegetative cells of B. cereus were completely killed with minimum bactericidal concentration (MBC) of 8 μg/mL of macelignan. Killing time of macelignan against vegetative cells of B. cereus was very fast; endpoint of macelignan was reached after 4 hr of incubation at 4×MIC. Macelignan inactivated more than 3-log (99.9%) of spores/mL of B. cereus at the concentration of 100 μg/mL. Macelignan was found to be effective against vegetative cells and spores of B. cereus. These results suggest that macelignan might be good to be developed as a food preservative.

This study evaluated the effects of γ-irradiation on immunomodulating properties and structural changes of β-glucan. β- Glucan solutions (10 mg/mL) were γ-irradiated at 10, 30, and 50 kGy. Splenocyte proliferation and cytokine (interferon-γ and interlukin-2) productions by γ-irradiated β-glucan were evaluated in in vivo and in vitro, and structural changes of β-glucan were also determined after γ-irradiation. γ-Irradiation on β-glucan at 50 kGy enhanced splenocyte proliferation and cytokine productions, (p<0.05) and cleft glycosidic bonds of β-glucan resulting in lower the molecular weight. These results indicate that the use of γ- irradiation on β-glucan may be useful for improving its immunological activity by lowering the molecular weight of β-glucan.