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The pine wood nematode ( Bursaphelenchus xylophilus ) causes pine wilt disease, which is a major problem affecting pine forests. This study aimed to identify metabolites from Sparassis latifolia that have nematicidal activity and to investigate the effect of water-soluble formulations of the active compounds for use as trunk-injectable control agents against the nematode B. xylophilus . When the submerged cultures of S. latifolia were bioassayed against B. xylophilus , strain KFRI 747 showed the most potent activity (52.8%), followed by KFRI 1080 (44.4%) and KFRI 645 (34.8%); their activities were correlated with the concentration of sparassol in their mycelia. Six fractions (SLE1-6) were obtained from ethyl acetate extracts of the liquid culture medium; nematicidal activity was found only in SLE4 (which included sparassol). Sparassol bioassayed against B. xylophilus and had LC 50 and LC 95 of 84.92 and 132.13 ppm, respectively. Sparassol was modified to disodium sparassol using NaOH because sparassol was not water-soluble and thus was not useful as an agent for trunk injection. Disodium sparassol exhibited similar nematicidal activity to that found with sparassol. The trunk-injectable nematicides (abamectin and emamectin benzoate) were more effective than sparassol and disodium sparassol in terms of LC 50 and LC 95 values. However, sparassol has a more simple chemical structure than these compounds and could be more easily synthesized. To our knowledge, this is the first report indicating that disodium sparassol might be useful as nematicide for use against the pine wood nematode. [ABSTRACT FROM AUTHOR]

Bacillus cereus was divided into emetic toxin (cereulide)- and enterotoxin-producing strains, but emetic toxin-producing B. cereus is difficult to detect immunochemically. Screening methods for emetic toxin-producing B. cereus are needed. The objectives of this study were to identify and detect emetic toxin-producing B. cereus among 160 B. cereus strains, and to compare enterotoxin production and phenotypic characteristics between the emetic toxin-producing and enterotoxin-producing strains. Forty emetic toxin-producing B. cereus strains were determined with high-pressure liquid chromatography-mass spectrometry analysis. Among the emetic toxin-producing strains (n = 40), 31 (77.5%) and 3 (7.5%) strains produced nonhemolytic enterotoxin (NHE) and hemolysin BL (HBL) enterotoxins, respectively. In addition, 107 (89.2%) and 100 (83.3%) strains produced NHE and HBL enterotoxins among the enterotoxin-producing strains (n = 120). The number of strains positive for starch hydrolysis, salicin fermentation, and hemolysis among the emetic toxin-producing strains were 3 (7.5%), 3 (7.5%), and 26 (65.0%), respectively, and among enterotoxin-producing strains, these numbers were 101 (84.2%), 100 (83.3%), and 111 1 (92.5%), respectively. In particular, the three emetic toxin-producing B. cereus strains (JNHE 6, JNHE 36, and KNIH 28) produced the HBL and NHE enterotoxins and were capable of starch hydrolysis and salicin fermentation. The absence of HBL enterotoxin and certain phenotypic properties, such as starch hydrolysis and salicin fermentation, indicates that these properties were not critical characteristics of the emetic toxin-producing B. cereus tested in this study. [ABSTRACT FROM AUTHOR]

Abstract: Ninety two samples of child-consumed candies and candy packages were analyzed for seven heavy metals. Lead (Pb) was detected at concentrations of 110.3–6394.1mgkg−1 in ten of 92 candy packages. The directive factor of Pb contamination had originated in the lead-based ink of the outer cover. Particularly, Pb was detected at high concentrations in case of green- or yellow-colored packages. Chromium (Cr) was detected at high concentrations in cases where Pb was also detected at high concentrations, and the Cr levels ranged from 136.9mgkg−1 to 1429.3mgkg−1 in seven of the 92 candy packages. Hexavalent chromium [Cr(VI)] was detected at 87–105.0% of the total Cr in polypropylene-coated wrappers with printed outer covers. The migration of Cr(VI) increased with elution time up to 0.20μg (cm2)−1 for 30 days in basic (pH 10.0) solution; however, there were no migrations in acidic (pH 4.0) and neutral (pH 7.0) solutions. The migration of Pb increased with elution time up to 0.65μg (cm2)−1 and 0.28μg (cm2)−1 in basic (pH 10.0) and acidic (pH 4.0) solutions, respectively. However, any migration was hardly observed in neutral (pH 7.0) solution. [Copyright &y& Elsevier]

Abstract: Bacillus cereus can cause the diarrheal and emetic type of food poisoning but the symptoms of emetic food poisoning caused by B. cereus occasionally include emesis and diarrhea. The enterotoxin characteristics of emetic toxin (cereulide) producing B. cereus were needed to be determined. Therefore, forty B. cereus strains isolated from various sources in Korea were investigated for the presence of enterotoxin genes. All strains were confirmed to produce the emetic toxin using HPLC-MS methods. The rates of the nheABC, hblCDA, entFM and cytK genes amongst emetic toxin producing B. cereus strains were 82.5, 7.5, 50.0 and 27.5%, respectively. Pattern III harbored nheABC and entFM genes and pattern V processed entFM gene and were shown to be the major patterns, being present in 55.0% (21 of 40) of the emetic toxin producing B. cereus strains. Our findings revealed that 34 (85.0%) of 40 emetic toxin producing B. cereus strains isolated in Korea have the potential to cause diarrheal and emetic type of food poisoning, simultaneously. Thus, emetic toxin and enterotoxin genes should be constantly screened to provide insight into B. cereus food poisoning. [Copyright &y& Elsevier]