We have been attempting for some time to discover a compound evidencing antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). The dieckol isolated from Ecklonia stolonifera has been shown to exhibit antibacterial activity against methicillin-susceptible S. aureus (MSSA) and MRSA. The minimum inhibitory concentrations (MICs) of dieckol were determined in a range of 32 to 64 μg/mL against standard MSSA and MRSA strains. Furthermore, dieckol clearly reversed the high-level ampicillin and penicillin resistance of MRSA. The MICs of ampicillin against two standard strains of MRSA were dramatically reduced from 512 to 0.5 μg/mL in combination with 1/4 MIC of dieckol (16 μg/mL). The fractional inhibitory concentration (FIC) indices of ampicillin and penicillin were measured from 0.066 to 0.266 in combination with 8 or 16 μg/mL of dieckol against all tested MRSA strains, thereby suggesting that dieckol-ampicillin or dieckol-penicillin combinations exert a synergistic effect against MRSA. The results of this study indicate that dieckol, administered in combination with β-lactams, may prove effective in the treatment of MRSA infections. Our finding may also contribute to the development of an alternative phytotherapeutic anti-MRSA agent. © KSBB

This study was conducted to investigate the sensory interactions between various organic acids and flavorants in 3 types of ramen soup ('beef,' seafood, and 'kimchi') when types and levels of organic acids (citric, malic, and lactic) varied. For 'beef' and seafood ramen soup, weak suprathreshold levels of acids (0.0039% to 0.0071%) were applied to the system and medium suprathreshold of acids (0.0128% to 0.0299%) were applied to the kimchi ramen soup. The amount of acid applied to each system was chosen based on the equiweight level. Descriptive analyses were performed separately for each ramen soup system using 8 trained panelists. A total of 11, 13, and 12 flavor descriptors were generated for 'beef,' seafood, and 'kimchi' soup, respectively. Analysis of variance was conducted to evaluate the effect of organic acid on the sensory characteristics of ramen soup. Principal component analysis was conducted to summarize the relationship between the soup samples and attributes. The effect of organic acids on the flavor attributes of ramen soup was dependent on the soup system as well as adding levels of acid. Addition of lactic acid power (at 0.0066%) in 'beef'ramen soup showed enhancement effect on the sour, salty, beefy, 'mushroom' flavor, and fermented soybean paste soup flavor, whereas lactic acid powder (at 0.0071%) showed enhancement effect only on the sour and fermented soybean paste soup flavor in seafood ramen soup due to the strong 'hot' flavor characteristics of the soup. In kimchi ramen soup, flavor attributes congruent to sourness were enhanced by the addition of organic acids to the system.

Insecticidal and acaricidal responses of Cinnamomum cassia oils made by organic solvent (OS), steam distillation (SD), and supercritical fluid (SF) and their components were examined in two bioassays (contact and fumigant bioassays) against Plodia interpunctella, Sitophilus oryzae, S. zeamais, Tyrophagus putrescentiae, and Sitotroga cerealella adults. Using the contact or fumigant bioassay against T. putrescentiae adults, OS oil exhibited the strongest toxicities (50% lethal dose [LD 50 ], 2.60 lg/ cm 2 and 1.34 lg/cm 3), followed by SF and SD oils. Furthermore, using two bioassays, SD oil against S. oryzae and S. zeamais adults exhibited the strongest toxicities (LD 50 , 102.25 lg/cm 2 and 68.62 lg/cm 3 , 102.03 lg/cm 2 and 57.59 lg/cm 3), followed by SF and OS oils. Using the fumigant bioassay against S. cerealella and P. interpunctella adults, OS oil exhibited the strongest toxicities (LD 50 , 1.17 lg/cm 3 and 0.79 lg/cm 3) followed by SF and SD oils. Cinnamaldehyde, cinnamyl acetate, and coumarin against T. putrescentiae adults showed no significant differences in the contact bioassay, but in the fumigant bioassay, cinnamaldehyde exhibited the highest toxicity (LD 50 , 0.91 lg/cm 3) followed by cinnamyl acetate and coumarin. Against S. oryzae, S. zeamais, S. cerealella, and P. interpunctella adults, cinnamaldehyde using two bioassays exhibited the most potent toxicities (LD 50 , 108.81 lg/ cm 2 and 77.80 lg/cm 3 , 104.72 lg/cm 2 and 36.48 lg/cm 3 , 0.57 lg/cm 2 and 2.29 lg/cm 3), followed by coumarin and cinnamyl acetate in order. The results showed that cinnamaldehyde and the C. cassia oils could be effective values in the management of stored product pests. Keywords Acaricidal responses Á Cinnamomum cassia Á Plodia interpunctella Á Sitotroga cerealella Á Sitophilus oryzae Á Tyrophagus putrescentiae

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Essential oils of Coriandrum sativum were extracted by three different methods, including steam distillation (SDE), solvent (SE) and supercritical fluid extraction (SFE), to determine their acaricidal and insecticidal properties against Plodia interpunctella, Sitotroga cerealella and Tyrophagus putrescentiae. The fumigant bioassay against P. interpunctella, S. cerealella and T. putrescentiae revealed the strongest activity (LD 50 9.38, 18.76 and 4.19 lg/cm 3) of oil obtained via SDE, followed by extraction via SE (LD 50 [ 75.20, 21.11, and [ 75.20 lg/cm 3) and SFE (LD 50 [ 75.20, 27.36, and [ 75.20 lg/ cm 3). The contact bioassay against T. putrescentiae revealed the most potent activities of oil obtained via SDE (LD 50 19.29 lg/cm 2), followed by oil via SE and SFE. The chemical composition of C. sativum oils obtained by SDE, HE and SFE was analyzed by GC-MS. The C. sativum oil obtained by SDE contained linalool (66.80%) compared with oils obtained by SE and SFE (70.67-70.80%). However, camphor (6.46%) was detected in SDE but not in the other two extracts. Based on the LD 50 values of six major compounds derived from the three C. sativum oils against P. interpunctella, S. cerealella and T. putresceentiae, camphor was considered the most active (2.32, 19.31 and 3.24 lg/cm 3 , respectively) insecticide. The three values were about real camphor concentration in the oil via SDE. These results indicate that camphor contributes to the acaricidal and insecticidal activities of oil extracted via SDE of C. sativum seeds.