Formation of central cleavage products from lycopene analogues under liposomal suspension

Seon-Jae Kim, Jae-Ho Hwang, Kyeong-Ho Han

Abstract
The decrease of lycopene analogues (60 μM) and the formation of its central cleavage products were quantitatively evaluated during the course of autoxidation at 37°C for 72 h in liposomal suspension. The amounts of central cleavage as carbonyl compounds, acycloretinal, phytofluenal (from ζ-carotene), and phytofluenal (from phytofluene), reached maxima of 36.7, 26.5, and 23.6 nM after 48 h incubation, respectively, while carboxyl cleavage, acycloretinoic acid, 4,5-didehydrogeranyl geranoic acid (from ζ-carotene), and 4,5-didehydrogeranyl geranoic acid (from phytofluene) were reached to 4.6, 3.8, and 3.3 nM at 48 h incubation.

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Keywords : lycopene analogue ,liposomal suspension ,autoxidation ,central cleavage product.

Determination of biogenic amines in Japanese miso products

Shruti Shukla, Hae-Kyong Park, Jong-Kyu Kim, Myunghee Kim

Abstract
Eight miso products sold in supermarket were purchased from Japan and analyzed for the determination of biogenic amines (BAs). Quantitative determination of BAs in miso products was carried out by means of HPLC with spectrophotometric UV-VIS detector. The amines were extracted in acid aqueous solution (HClO4) and then derivatized by dansyl chloride. The levels of pH in the tested miso samples were ranged from 4.8–5.5. The BAs (tryptamine, 2-phenyl ethylamine, putrescine, cadaverine, agmatine, tyramine, and spermidine) determined in 8 miso samples were found in their respective range of ND-0.13, ND-4.20, ND-1.29, ND-0.87, ND-0.90, ND-4.19, and ND-3.57 mg%. None of the miso samples contained histamine and spermine, the major BAs of food poisoning.

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Keywords :,miso,biogenic amine,dansyl chloride derivatization,HPLC.

Neuronal cell protective effect of aerial parts of Chinese lizard’s tail (Saururus chinensis (Lour.) Baill.)

Hee-Rok Jeong, Chang-Ho Jeong, Ji Hyun Kwak, Ji Hye Kim, Uk Lee, Gwi Nam Choi, Sung-Gil Choi, Ho Jin Heo

Abstract
The antioxidant and neuronal cell protective effects of silica-gel open column chromatographic fractions, obtained from Chinese lizard’s tail (Saururus chinensis) methanolic extract, were investigated. The ABTS radical scavenging and ferric reducing antioxidant power (FRAP) assays indicated that the SC4 fraction (eluted with chloroform/methanol by 4:1, v/v) obtained from Chinese lizard’s tail was more potent radical scavengers and reducing agents than that of other 5 fractions. The SC4 fraction also presented protective effects against H2O2-induced neurotoxicity in a dose-dependent manner. Therefore, our study suggested that the SC4 fraction has strong antioxidant and neuronal protective effects which are correlated with its high level of phenolics, particularly quercitrin and quercetin.

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Keywords : Chinese lizard’s tail (Saururus chinensis (Lour.) Baill.) ,quercitrin ,quercetin ,antioxidant ,neuronal protective effect.

Anti-allergic effect of low molecular weight β-glucan prepared by λ-irradiation

Nak-Yun Sung, Jong-il Choi, Yohan Yoon, Soo-Young Lee, Myung-Woo Byun, Yeoung-Jung Hwang, Zubaidah Irawati Koenari, Ju-Woon Lee, Jae-Hun Kim

Abstract
This study evaluated the anti-allergic effect of low molecular weight β-glucan (25 kDa) degraded by λ-irradiation. Allergy was induced in mouse models administrated with λ-irradiated low molecular weight and non-irradiated high molecular weight β-glucan, respectively, for 7 days. However, only the mice treated with low molecular weight β-glucan had a significantly decreased the total serum IgE and ovalbumin specific-IgE levels, and significantly increased Th 1 cytokine expression compared to only allergy induced mice. The allergic responses could be reduced by low molecular weight β-glucan treated λ-irradiation through the increased expression of Th 1 response and decreased expression of total IgE and antigen specific IgE.

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Keywords : allergy ,β-glucan ,low molecular weight ,cytokine.

Analysis of acrylamide using gas chromatography-nitrogen phosphorus detector (GC-NPD)

Sim Hae Kim, Jun-Ho Hwang, Kwang-Geun Lee

Abstract
In this study, an improved analytical method for the quantification of acrylamide using a GC-nitrogen phosphorus detector (GC-NPD) was developed. This method showed reasonable recovery, sensitivity, and accuracy in monitoring acrylamide levels. The optimum solvent for the extraction of acrylamide was ethyl acetate. The linear response of acrylamide concentrations ranged between 0.5–100 ppm (μg/mL) with a correlation coefficient of 0.999. The limit of quantification (LOQ) was 0.5 ppm, and the recovery rate was 106±8%. The acrylamide level of fried potato sold in local restaurant was 2.7±0.3 ppm. Thus, a new protocol combining GC-NPD and LC-tandem mass spectrometry (MS/MS) could be applied to analyze acrylamide accurately and precisely, contributing to the development of a prescreening tool to analyze acrylamide in the food industry.

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Keywords : acrylamide ,GC-nitrogen phosphorus detector (GC-NPD) ,analytical method ,prescreening method ,monitoring.

Screening of Korean edible wild plants for estrogenic activity using MCF-7 cell proliferation assay

Young Min Lee, Ho Young Jung, Ji Hyun Bae, Jin Young Lee, Hwan Hee Jang, Dong Sik Park, Jae-Hyun Kim

Abstract
This present study was performed to investigate estrogenic activity of Korean edible wild plants for alternative of estrogen replacement therapy in postmenopausal women. When the estrogenic activity was measured by estrogen induced proliferation of MCF-7 cells, of investigated 29 extracts, 3 samples of kudzu vine (Pueraria thunbergiana), Cardamine leucantha, and David Vetchling (Lathyrus davidii) exhibited a significant proliferation of above 20% at concentration of 100 μg/mL. This stimulation of MCF-7 cell proliferation could be completely blocked by addition of estrogen antagonist ICI 182,780 (100 nM), indicating estrogen receptor-dependent mechanism of these estrogenic effects on MCF-7 cell proliferation.

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Keywords: MCF-7 proliferation assay,estrogenic activity,Korean wild plant.

Simultaneous determination of macrolide residues in fish and shrimp by liquid chromatography-tandem mass spectrometry

Mi Ra Jo, Hee Jung Lee, Tae Seek Lee, Kunbawui Park, Eun Gyoung Oh, Poong Ho Kim, Doo Seog Lee, Masakazu Horie

Abstract
A sensitive and selective analytical method for 7 macrolides determination by LC-tandem mass spectrometry (LC-MS/MS) in fish and shrimp was developed. Samples were extracted by liquid-liquid extraction steps using 70% acetonitrile. The positive ionization produced the molecular related ions, (M+2H)2+, at m/z 422.3 for spiramycin I, and (M+H)+, at m/z 734.5, 772.4, 828.4, 837.4, 916.5, and 814.4 for erythromycin A, kitasamycin, josamycin, roxithromycin, tylosin A, and oleandomycin, respectively, were the precursor ions for collision-induced dissociation (CID) and 2 diagnostic product ions for each analyte were identified to carry out selected reaction monitoring (SRM) LC-MS/MS analyses. The recovery rates of macrolides in fish and shrimp samples were in the range 68.2–89.0, 72.8–91.6% and 75.2–87.0, 64.4–83.2% for the concentration of 50 and 100 ng/g, respectively.

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Keywords: macrolide antibiotics,LC-tandem mass spectrometry (LC-MS/MS),fish,shrimp.

Study of α-, γ-, and δ-tocopherols in the oxidative stability of lard

Robert E. King, David B. Min, Sea Cheol Min

Abstract
Effects of α-, γ-, and δ-tocopherols at 0, 50, 100, 250, 500, and 1,000 ppm on the oxidative stability of lard during storage in the dark at 55°C for 7 days were studied by determining headspace oxygen content and peroxide value. The headspace oxygen content of the lard without tocopherol addition decreased from 21.1 to 14.4% and the peroxide value increased from 2.5 to 15.4 meq/kg lard for 7 days. The headspace oxygen depletion and the peroxide value of lard decreased by the addition of α-tocopherol at 50 ppm, but significantly increased at 250, 500, or 1,000 ppm. As the concentration of γ-tocopherol or δ-tocopherol increased, the headspace oxygen depletion and the peroxide value decreased. α-Tocopherol at 250 ppm acted as a prooxidant in the autoxidation of lard. The concentrations of γ- or δ-tocopherol to be applied to improve the autoxidative stability of lard may be 100–250 ppm.

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Keywords: lard,oxidative stability,α-tocopherol,γ-tocopherol,δ-tocopherol.

Discrimination of palm olein oil and palm stearin oil mixtures using a mass spectrometry based electronic nose

Eun Jeung Hong, Sue Jee Park, Jin Young Choi, Bong Soo Noh

Abstract
To discriminate mixing ratios for mixtures of palm olein oil and palm stearin oil, an electronic nose based on mass spectrometer (MS-electronic nose) and GC were used. The intensities of each fragment from the palm olein oil and palm stearin oil by the MS-electronic nose were used for discriminant function analysis (DFA). When palm olein oil is mixed with palm stearin oil, more than 3% of stearin oil can be estimated by DFA. The obtained data were used for DFA. DFA plot indicated a significant separation of pure palm olein oil and palm stearin oil. The added concentration of palm stearin oil to palm olein oil was highly correlated with the first discriminant function score (DF1). When palm stearin oil was added to palm olein oil, it was possible to predict the following equation; DF1= −0.112×(conc. of palm stearin oil)+0.416 (r2=0.95). When palm stearin oil was added to palm olein oil, peak area of GC was correlated to DF1 by MS-electronic nose with ratio of palm olein oil vs palm stearin oil. The MS-electronic nose system could be used as an efficient method for the authentication of oil.

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Keywords : electronic nose,mass spectrometer,palm olein oil,palm stearin oil,GC-flame ionization detector (GCFID).

Recovery of arbutin in high purity from fruit peels of pear (Pyrus pyrifolia Nakai)

Jeong-Yong Cho, Keun Young Park, Ki Hoon Lee, Hyoung Jae Lee, Sang-Hyun Lee, Jeong An Cho, Wol-Soo Kim, Soo-Cheol Shin, Keun-Hyung Park, Jae-Hak Moon

Abstract
β-Arbutin is one of the most abundant compounds in pear fruit and has been widely used as a whitening agent in cosmetic products. In this study, a simple method for the purification and isolation of arbutin in high purity from the fruit peel of a pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) was developed. The high extraction efficiency of arbutin was accomplished with 80% ethanol under acidic conditions (pH 3.0). In the partition between water and ethyl acetate, almost all of the arbutin (78%) was detected in the water layer. Therefore, arbutin was further purified and isolated from the water layer using Diaion HP-20 column chromatography and preparative HPLC. The isolated arbutin represented a 60% recovery with a purity exceeding 99%.

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Keywords: pear,Pyrus pyrifolia,fruit peel,arbutin,Diaion HP-20 column chromatograpy.

Influence of emulsion droplet size on antimicrobial properties

Umaporn Buranasuksombat, Yun Joong Kwon, Mark Turner, Bhesh Bhandari

Abstract
In this study the effect of oil droplet size on antimicrobial activity was investigated. Oil-in-water emulsions were made from oil possessing antimicrobial properties (lemon myrtle oil, LMO), and oil which has no antimicrobial properties (soybean oil). The antimicrobial properties were investigated against 5 bacteria. The emulsions containing millimetre size and micron-size droplets were produced by hand-shaking and blending using a high speed blender and nanoemulsions were produced using a microfluidizer at 60 MPa. It was found that all emulsions made from LMO had the same level of antimicrobial effects against the 5 bacteria whereas all soybean oil emulsions had no antimicrobial effect. From these results, it could be concluded that the antimicrobial property of nanoemulsions result from the active ingredients in the emulsions and not from high surface tensions and cell wall diffusion activity of nano-sized droplets.

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Keywords :nanoemulsion,antimicrobial property,lemon myrtle oil,microfluidization,droplet size.

Total phenolic content, antioxidant activity, and type II diabetes related functionality of traditionally processed ox-eye bean [Mucuna gigantea (Willd) DC.] seeds: An Indian underutilized food legume

Vellingiri Vadivel, Hans Konrad Biesalski

Abstract
The methanolic extract of ox-eye bean [Mucuna gigantea (Willd) DC.] contained total free phenolic content of 14.80±1.28 g catechin equivalent/100 g extract dry matter. Encouraging levels of ferric reducing/antioxidant power (FRAP, 1,023 mmol Fe[II]/mg extract), inhibition of β-carotene degradation (59.35%) and radical scavenging activity against DPPH (72.12%) and superoxide (43.11%) were exhibited by the raw samples. Further, it also recorded 82.17% of α-amylase and 91.26% of α-glucosidase enzyme inhibition characteristics. Sprouting+oil-frying caused a apparent increase on the total free phenolic content and also significant improvement on the antioxidant and free radical scavenging capacity of methanolic extract, while soaking+cooking as well as open-pan roasting treatments showed diminishing effects. Moreover, inhibition of α-amylase and α-glucosidase enzyme activities was declined to 22.82 and 45.47%, respectively during sprouting+oilfrying treatment, which are more desirable for the dietary management of type II diabetic patients.

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Keywords: ox-eye bean (Mucuna gigantean),total free phenolics,antioxidant activity,α-amylase inhibition,α-glucosidase inhibition,indigenous processing ,method.

Volatile distribution in garlic (Allium sativum L.) by solid phase microextraction (SPME) with different processing conditions

Na Young Kim, Min Hee Park, Eun Yeong Jang, JaeHwan Lee

Abstract
Treatments of autoclaving, high temperature aging (aged-black garlic), crushing, and roasting at 100, 150, and 200°C were applied to alter the volatile profiles of garlic (Allium sativum L.). Headspace volatiles in samples were analyzed by a solid phase microextraction (SPME)-GC/MS. Total peak areas of crushed-raw garlic were the highest and those of aged-black garlic clove were the lowest. Crushing effects were clearly observed in raw garlic, aged-black garlic, and roasted garlic at 200°C for 60 min. Sulfur-containing volatiles including diallyl disulfide and diallyl trisulfide were major volatiles. Generally, peak areas of diallyl disulfide decreased when garlic received autoclaving and roasting treatment while diallyl trisulfide and allyl methyl trisulfide increased during heat treatment compared to raw garlic. Roasting at 200°C for 60 min caused the formation of pyrazines greatly in garlic. Principal component analysis (PCA) for the volatile profiles by SPME-GC/MS could discriminate types of processed garlic successfully.

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Keywords: garlic,headspace volatiles,processing effect,phase microextraction.

Effect of washing treatments on pesticide residues and antioxidant compounds inYuja (Citrus junos Sieb ex Tanaka)

Jung-Min Sung, Ki-Hyun Kwon, Jong-Hoon Kim, Jin-Woong Jeong

Abstract
This study investigated the removal efficiency of pesticide residues and microorganisms, and changes of the amount of antioxidant compounds on yuja (Citrus junos Sieb ex Tanaka) by various washing methods. The washing methods were mechanical washing (MW), mechanical washing after soaking in SAcEW, strong acidic electrolyzed water (SAcEW+MW), and soaking detergent solution (DW), with a tap water washing (TW) as the control. After treatment of MW and SAcEW+MW, the microbial count were 3.71 and 2.66 log CFU/g, respectively. Compared with the TW treatment (5.77 log CFU /g), MW and SAcEW+MW treatments showed a higher reduction. As a result of pesticide residue, the SAcEW+MW removed 70.5–98.1% and was the most effective, regardless of the pesticides. Antioxdant activities, as measured by DPPH radical, ranged from 20.36 to 21.27% and there was no significant difference from the washing methods. The results of this study demonstrated that the SAcEW+MW was the most effective method for removing residual pesticides without affecting the quality of the yuja.

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Keywords: antioxidant activity,hesperidin,microbial reduction,pesticide residues,yuja.

Effects of sodium hypochlorite and acidified sodium chlorite on the morphological, microbiological, and sensory qualities of selected vegetables

Kyung Yoon Kwon, Kyung Ah Kang, Ki Sun Yoon

Abstract
The effects of washing with sodium hypochlorite (NaClO) and acidified sodium chlorite (ASC) on the reduction of various pathogens contaminated produce, as well as the change in sensory qualities during storage and morphological characteristics of the surface of the washed produce, including cherry tomato, cucumber, and carrot were evaluated. Produce was inoculated with Bacillus cereus, B. cereus spore, Campylobacter jejuni, Salmonella Typhimurium, and Listeria monocytogenes and then washed with 100, 150, or 200 ppm NaClO and stored for 11 days at 4°C. The produce contaminated with S. Typhimurium or L. monocytogenes was also washed with 100 ppm NaClO containing 5% acetic acid and 500 ppm ASC. The greatest washing efficacy was observed in B. cereus, followed by S. Typhimurium, L. monocytogenes, and C. jejuni. NaClO with 5% acetic acid was significantly (p<0.05) more effective than 500 ppm ASC at S. Typhimurium, but not at L. monocytogenes, regardless of the types of produce, while ASC was the most effective sanitizer for L. monocytogenes in cucumber. Scanning electron microscopy showed that washing with NaClO removed the pathogens, but also part of the wax layer from the surface, which might affect sensory qualities of the produce during storage.

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Keywords: produce,sanitizer,Salmonella Typhimurium,Listeria monocytogenes,scanning electron microscope.

Optimization and evaluation of heat-shock condition for spore enumeration being used in thermal-process verification: Differential responses of spores and vegetative cells of Clostridium sporogenes to heat shock

Bo Young Byun, Hong-Yon Cho, Han-Joon Hwang, Jae-Hyung Mah, Yanhong Liu, Juming Tang, Dong-Hyun Kang

Abstract
To evaluate a heat-shock condition for the enumeration of Clostridium sporogenes spores, a surrogate for C. botulinum spores, we examined the heat tolerance of C. sporogenes spores and vegetative cells exposed to a heat shock at 90°C. From the D values of the spores determined in the temperature range of 113–121°C, z value (±SD) and D90°C value were estimated to be 10.16±0.90°C and 1,071.52 min, respectively, and the inactivation rates were predicted to be only approximately 2% at 90°C for up to 10 min. Meanwhile, the viable count of spores was significantly higher when activated under a heat-shock condition of 90°C for over 9 min than those activated for shorter time periods. The heat tolerance of vegetative cells was extremely low, showing a D90°C value (±SD) of 0.21±0.01 min. Finally, 3 different heat-shock conditions were compared: 70°C for 30 min, 80°C for 20 min, and 90°C for 10 min, and the experimental comparative data showed no significant differences in viable spore counts. Consequently, these results support that the heat-shock treatment at 90°C for 10 min is suitable to activate spores and to inactivate vegetative cells of C. sporogenes.

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Keywords: Clostridium sporogenes,spore,vegetative cell,enumeration.
heat shock