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Antimicrobial activity of garlic (pH 6.0) heated at 120oC reached its maximum at 45min of heating andmaintained the level for the rest of heating time (300 min) when tested against Candida utilis ATCC42416. The principalantimicrobial compound was allyl alcohol (AA), a highly volatile compound without sulfur in its molecule. The concentrationof AA in heated garlic gradually increased to over 2,000 ppm for the first 90 min and stayed at the level without appreciablechanges in spite of further heating. Other antimicrobial compounds secondary to AA were lowly volatile sulfur compoundsincluding diallyl polysulfides (diallyl trisulfide, diallyl tetrasulfide, and diallyl pentasulfide) and heterocyclic sulfur compounds(4-methyl-1,2,3-trithiolane, 5-methyl-1,2,3,4-tetrathiane, and 6-methyl-1,2,3,4,5-pentathiepane). When the pH of the garlicextract was lowered before heating, considerably more secondary antimicrobial sulfur compounds were formed and theantimicrobial activity was stronger than the pH unadjusted garlic. Lowly volatile sulfur compounds contributed a significantpart of antimicrobial activity of heated garlic only during the early period (45-120 min) of heating regardless of pH treatment.

A putative cyclomaltodextrinase (BHCD) gene was found from the genome of Bacillus halodurans C-125, whichencodes 578 amino acids with a predicted molecular mass of 67,279 Da. It shares 42-59% of amino acid sequence identity withcommon cyclomaltodextrinase (CDase)-family enzymes. The corresponding gene was cloned by polymerase chain reaction(PCR) and the dimeric enzyme with C-terminal 6-histidines was successfully overproduced and purified from recombinantEscherichia coli. BHCD showed the highest activity against β-CD at pH 7.0 and 50oC. Due to its versatile hydrolysis andtransglycosylation activities, BHCD has been confirmed as a member of CDases. However, BHCD can be distinguished fromother typical CDases on the basis of its novel multisubstrate specificity. While typical CDases have over 10 times higher activityon β-CD than starch or pullulan, the CD-hydrolyzing activity of BHCD is only 2.3 times higher than pullulan. In particular, itshowed significantly higher activity ratio of maltotriose to acarbose than other common CDase-family enzymes.

In prion disease, spongiform neurodegeneration is preceded by earlier synaptic dysfunction. There is evidence thatsoluble N-ethylmaleimide sensitive factor attachment receptor (SNARE) complex formation is reduced in scrapie-infected invivo models, which might explain this synaptic dysfunction because SNARE complex plays a crucial role in neuroexocytosis.In the present study, however, it is shown that prion protein (PrP) does not interfere with SNARE complex formation of 3SNARE proteins: syntaxin 1a, SNAP-25, and synaptobrevin. Sodium dodecyl sulfate-resistant complex formation, SNARE-driven membrane fusion, and neuroexocytosis of PC12 cells were not altered by PrP. Thus, PrP does not alter synapticfunction by directly interfering with SNARE complex formation.

Gamma (γ)-irradiation can be used to control pathogens such as Vibrio vulnificus in seafood. The effects ofirradiation on microbial cell populations (%) have been studied in order to develop detection methods for irradiated foods. Themethod used in this study was ethidium bromide monoazide (EMA) real-time polymerase chain reaction (PCR), using V.vulnificus specific primer, EMA, and SYBR® Green to discriminate between γ-irradiated and non-irradiated cells. Confocalmicroscope examination showed that γ-irradiation damaged portions of the cell membrane, allowing EMA to penetrate cells ofirradidated V. vulnificus. γ-Irradiation at 1.08 KGy resulted in log reduction (−1.15±0.13 log reduction) in genomic targetsderived from EMA real-time PCR. The combination cold/heat shock resulted in the highest (−1.74±0.1 log reduction)discrimination of dead irradiated V. vulnificus by EMA real-time PCR.

The objectives of this present study were to compare the contents and determine optimum extraction conditions forthe rosmarinic acid (RA) and caffeic acid (CA) from leaves of Korean Perilla frutescens varieties. RA and CA from leaves ofcv. Bora, a breeding line of P. frutescens were isolated and elucidated using various spectroscopic data. On the basis of 2phenolic acids, optimum extraction conditions were obtained by employing 50% EtOH for 60 min at 25oC. We reported forthe first time on the contents of RA and CA from leaves of 32 Korean varieties. Among them, leaves of P. frutescens Brit. var.acuta Kudo I exhibited the highest RA content (8.53±0.57mg/g) and CA content (2.33±0.11mg/g) showed the highest in theP. frutescens Brit. var. viridis Makino. Interestingly, average RA content (2.66±0.17mg/g) showed a markedly higher thanthat of CA (1.98±0.16mg/g) in Korean varieties. These results suggest that concentrations of the RA and CA in P. frutescensleaves could be a key factor in the selection process of a high quality species.

The effect of germination on hydration and germination properties, and on the changes of fatty acids and aminoacids profiles of a brown rice ‘Keunnun’ (KN) with a large embryo was compared to ‘Ilpumbyeo’ (IP) with a normal embryo.A rapid germination up to 24 hr was observed in both brown rice cultivars, afterward decreased with germination time. At 60hr, the KN (86.0±4.24%) showed slightly lower germination capability than the IP (97.0±1.41%). Lower water uptake duringgermination was also found in the KN (1.22±0.02g) compared to the IP (1.59±0.05g). Major fatty acids were palmitic acid,oleic acid, and linoleic acid accounting for more than 95% of total fatty acids. The most abundant amino acid in both typeswas oleic acid, which was decreased during germination, whereas palmitic and linoleic acids were increased. Eight aminoacids were detected, and a remarkable increase in γ-amino butyric acid (GABA) during germination was observed. The KNwas characterized with higher tasty amino acids of aspartic acid, glutamic acid, glycine, and alanine.

Solid fats were esterified with solid phase of rice bran oil (S-RBO), palm stearin (PS), and conjugated linoleic acid(CLA) at 2 substrate mole ratios (S-RBO:PS:CLA of 1:1:2 and 1:3:4). The major fatty acids were palmitic, oleic, and CLAin 36 hr products. The solid fat content (SFC) of the 1:1:2 product was 12.8% while the SFC of 1:3:4 product was 45.1% at20oC. The SFCs after 20oC reduced when the reaction time increased from 1 to 36hr, suggesting that the change oftriacylglycerol species was augmented by extending reaction time.

The α-glucosidase inhibitory and antioxidant effects of water chestnut (Trapa japonica Flerov.) were assessed toexplore its possible use as an anti-diabetic agent. Methanol extracts of the fruit shell and meat of water chestnut were assayedfor inhibitory activity against yeast α-glucosidase and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity.Effect of fruit shell extract on postprandial glucose response was assessed. Compared with fruit meat, shell extract showedstronger inhibition against α-glucosidase with an IC50 of 273µg/mL. Oral administration of fruit shell extract (500mg/kg)significantly lowered the postprandial area under the glucose response curve to starch (1g/kg) in streptozotocin (STZ)-induceddiabetic rats (p<0.01). Compared with fruit meat, shell extract showed stronger scavenging activity against DPPH, with anIC50 of 27.1µg/mL. The results indicate that the fruit shell of water chestnut was effective in controlling postprandialhyperglycemia and exerted an antioxidant effect. Therefore, water chestnut may be useful in treating diabetes.

The effect of 4 seaweed extracts (Desmarestia viridis, Dictyopteris divaricata, Scytosiphon lomentaria, and Ishigeokamurae) on pro-inflammatory mediators as well as nuclear factor (NF)-κB in the stimulated Raw 264.7 cells wasinvestigated. They reduced iNOS and interlukin (IL)-1β expressions at transcription level. Of those, 3 extracts (D. divaricata,I. okamurae, and S. lomentaria) inhibited the COX-2 expression at translation level. IκB-α degradation was inhibited by D.divaricata and S. lomentaria extracts. Therefore, we concluded that the extracts from D. divaricata and S. lomentaria couldinhibit the activation of murine macrophage through the blocking of NF-κB activation.

Total phenol, total flavonoid, reducing powder, electron donating activity, ascorbic acid equivalent antioxidantcapacity, antimicrobial and antiproliferative activities of olive leaf extracts were investigated. The contents of total phenol andflavonoid were 257.48 and 92.33mg in 100g of olive leaf extract, respectively. The reducing power of the olive leaf extractincreased with concentration increasing. Electron donating activity was high in 100µg/mL treated olive leaf extract as95.20%. The ascorbic acid equivalent antioxidant capacity of the olive leaf extract was 68.93mg/g olive leaf extract. The oliveleaf extracts showed relatively high antimicrobial activity against Escherichia coli, Salmonella typhimurium, Bacillus cereus,Staphylococcus aureus, Listeria monocytogenes, and Pseudomonas aeruginosa. All of the cancer cell lines including MKN45,HCT116, NCI-H460, and MCF7 have 70-81% as effective growth inhibition.