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The article presents study on identification and evaluation of anti-inflammatory compounds from Kaempferia parviflora. The study identified 5,7-dimethoxyflavone (DMF), 5-hydroxy-3,7,3\4'-tetramethoxyflavone (TMF) and investigated their anti-inflammatory effects in rat basophilic leukaemia (RBL-2H3) cells stimulated with an immunoglobulin E (IgE) antigen. The study also found that DMF and TMF showed marked inhibition of the degranulation.

We examined whether immunochemical-based test kits designed for quantitative analysis of deoxynivalenol (DON) screening in grain crops are applicable to corn processing by-products. Commercially available test kits (two types of immunochromatographic kits and three types of ELISA kits) were used to assay three types of corn processing by-products and mixed feed. The results obtained with some kits were significantly different from those of LC-MS analysis. Since the differences might be caused by insufficient extraction of DON from samples, the extraction time of all kits was set to be 20 minutes, based on a study of the dependence of the amount of DON extracted on the shaking time. Moreover, the extract of corn processing by-products was acidic, resulting in inhibition of the antigen-antibody reaction, so neutralization and centrifugation processes were introduced to prevent denaturation of antibody. After these modifications, the recovery for all kits in assays of corn gluten meal was within the range of 80-120%, and all kits showed acceptable accuracy. The relative standard deviation (RSD) of repeatability tests for all kits was less than 11.3% for analyses of both corn processing by-products and mixed feeds, indicating good precision. The above results showed that the kits studied were applicable to the quantitative assay of DON in corn processing by-products and mixed feed after modifications as described in this paper.

Corn is a major ingredient of mixed feed, and it has been reported that corn may be contaminated with deoxynivalenol (DON). There is also a possibility of contamination with other trichothecenes. Recently, corn-derived products such as Distiller's Dried Grains with Solubles (DDGS), corn gluten feed and corn gluten meal have been introduced and used for mixed feed. However the actual occurrence of trichothecenes has not been sufficiently investigated. So, in this study, we analyzed DON and 6 other trichothecenes, i.e., 3-acetyl-deoxynivalenol (3AcDON), 15-acetyl-deoxynivalenol (15AcDON), T-2 toxin, HT-2 toxin, nivalenol, and fusarenon-X, in DDGS, corn gluten feed, corn gluten meal, and mixed feed containing corn-derived ingredients. The major trichothecenes identified in the samples tested were DON, 3AcDON and 15AcDON. In particular, DON, 3AcDON and 15AcDON were detected in most DDGS and corn gluten feed samples. Most samples of mixed feed contained DON and 15AcDON, but only one mixed feed sample contained 3AcDON. In contrast, corn gluten meal was contaminated with lower levels of these compounds than the other samples tested. Among 36 corn gluten meal samples, DON was detected in 24 and 15AcDON was detected in 20 samples. 3AcDON was not detected in any of the corn gluten meal samples.

A analytical method for simultaneous determination of 10 heterocyclic amines (HCAs) applicable to prepared foods on the market was studied. HCAs were extracted with acidic methanol, and then purified on a diatomaceous column and an ion-exchange column prior to LC-MS/MS. The method was validated within laboratory using three groups among the total diet samples (oils and fats, fish and shellfish, meat and eggs). The method showed good precision and trueness (as recovery) in duplicate analyses over 5 days, though there were some unsatisfactory results. Limits of detection (LOD) and quantification (LOQ) of the method were estimated from the deviation of the analytical results in samples spiked at a level of near 1 ng/g. In addition,13 groups of total diet samples, 27 items of retail food ready to eat and a few foods cooked in the laboratory were analyzed using this validated method. The results showed that the method is applicable to the foods tested in this study and provided information on the content of HCAs in some foods in Japan.

A highly sensitive analysis method for six aflatoxins (aflatoxin B₁, B₂, G₁, G₂, M₁ and aflatoxicol) in rainbow trout muscle and liver was developed. Aflatoxins (AFs) were extracted with acetonitrile-water (9 : 1), purified on an immunoaffinity column, and subjected to HPLC with fluorescence detection after post-column photochemical derivatization. The recoveries of AFs at 0.05 μg/kg spiking levels were 71.4-82.4% in muscle and 80.1-93.0% in liver, and the repeatability relative standard deviations (RSDr) were 0.87-4.6% in muscle and 2.0-6.2% in liver. Limits of quantitation (LOQs) and limits of detection(LODs)of AFs were estimated to be 0.004-0.029 μg/kg, and 0.002-0.012 μg/kg, respectively.

A novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for trace residue determination of bicozamycin (BZM) in livestock products and seafoods. BZM was extracted from a sample with acetonitrile-water (4 : 1), followed by a two-stage SPE enrichment and cleanup. The first stage involved a styrene-divinylbenzene copolymer cartridge (GL-Pak PLS-2), and the second stage involved a divinylbenzene-N-vinylpyrrolidone copolymer cartridge (Oasis HLB). The LC separation was performed on a C18 column using 0.01% formic acid-methanol (8 : 2) as the mobile phase and MS detection with negative ion electrospray ionization. The mean recoveries from swine muscle, liver, yellowtail, and milk fortified at the minimum residue limit (MRL) levels and 0.01 microg/g were >70%, and the relative standard deviations (RSDs) were <20%. Limits of quantitation (LOQs) ranged from 0.002 to 0.005 microg/g.

A novel liquid chromatographic/tandem mass spectrometric (LC/MS/MS) method was developed for the trace residue determination of chloramphenicol (CAP) in bee pollen. CAP was extracted from bee pollen with a mixture of methanol and 1% metaphosphoric acid solution, followed by a 2-stage solid-phase extraction enrichment and cleanup. The first stage involved a polymeric cartridge, and the second stage involved an alumina neutral cartridge. The LC separation was performed on a C18 column with 10 mM ammonium formate-acetonitrile (7 + 3) as the mobile phase and MS detection with negative-ion electrospray ionization. CAP-d5 was used as the internal standard. The method was validated according to Commission Decision 2002/657/EC. The calibration curves were linear between 0.1 and 5.0 ng/mL, and overall recoveries ranged from 98 to 113%. Decision limits (CCalpha) ranged from 0.05 to 0.07 microg/kg, and detection capabilities (CCbeta) ranged from 0.08 to 0.12 microg/kg. The developed method was applied to 11 samples.

A simple and rapid LC/MS method for simultaneous determination of sedecamyin (SCM) and terdecamycin (TDM) in livestock products has been developed. SCM and TDM were extracted with acetonitrile. The extract was washed with n-hexane and then evaporated to dryness. The residue was dissolved in methanol, and injected into the LC/MS. The mass spectrometer was operated in the positive electrospray ionization (ESI) mode. LC separation was performed on a high-pH-resistant C18 column with 10 mmol/L carbonic acid-ammonia buffer (pH 10.0)-acetonitrile as a mobile pahse. The recoveries from swine muscle and liver fortified at the levels of 0.01 and 0.05 microg/g were 77-88%, and those from poultry muscle and liver fortified at the levels of 0.01 and 0.3 microg/g were 51-93%. The quantitation limits of SCM and TDM were 0.008 microg/g and 0.005 microg/g, respectively.

Inter-laboratory evaluation studies were conducted for ELISA methods for allergic substances (peanuts). Extracts of biscuit, sauce, chocolate and butter spiked with peanut standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Peanut Protein ELISA Kit (Peanut kit) and a FASTKIT Peanut ELISA kit (Peanut ELISA kit) were mostly below 10%. Mean recoveries of the peanut standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of peanut standard protein in four food extracts were in the ranges of 15.2-49.7% and 3.0-28.3% for the Peanut kit and the Peanut ELISA kit, respectively. Reproducibility relative standard deviations of peanut standard protein in four food extracts were 23.5-44.4%, 9.6-28.4% for the Peanut kit and the Peanut ELISA kit, respectively. The detection limits of both ELISA methods were 2-2.5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of peanut protein levels in extracts of biscuit, sauce, chocolate and butter.

Inter-laboratory evaluation studies were conducted for the ELISA methods for allergic substances (buckwheat). Extracts of snack, bun and udon spiked with buckwheat standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate at 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Buckwheat Protein ELISA Kit (Buckwheat kit) and a FASTKIT Buckwheat ELISA kit (Buckwheat ELISA kit) were mostly below 10%. Mean recoveries of the buckwheat standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of buckwheat standard protein in three food extracts were in the ranges of 6.8-78.5% and 5.0-33.9% for the Buckwheat kit and the Buckwheat ELISA kit, respectively. Reproducibility relative standard deviations of buckwheat standard protein in three food extracts were 11.9-69.5% and 16.5-34.1% for the Buckwheat kit and the Buckwheat ELISA kit, respectively. The detection limits of both ELISA methods were 1 ng/mL in sample solutions. These results suggest that the notified ELISA methods are reliable and reproducible for the inspection of buckwheat protein levels in extracts of snack, bun and udon.

Extracts of sausage, sauce, pasta sauce, fish paste and cereal spiked with wheat standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of both ELISA methods using a Wheat Protein ELISA Kit (Gliadin kit) and a FASTKIT Wheat ELISA Kit (Wheat ELISA kit) were mostly below 10%. Mean recoveries of the wheat standard protein from the food extracts were over 40% in the two ELISA methods except those from cereal extract determined using the Wheat ELISA kit. Repeatability relative standard deviations of wheat standard protein in the five food extracts were in the ranges of 16-26.9% and 3.7-36.2% for the Gliadin kit and the Wheat ELISA kit, respectively. Reproducibility relative standard deviations of wheat standard protein in the five food extracts were 21.6-38.5%, 29.7-53.8% for the Gliadin kit and the Wheat ELISA kit, respectively. The recoveries of wheat standard protein from the cereal extract were improved by the increasing the amount of antibody coated on the plate in the Wheat ELISA kit. The detection limits of both ELISA methods were 1 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of wheat protein levels in extracts of sausage, sauce, pasta sauce, fish paste and cereal.