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Background: RIDASCREEN® Histamine (enzymatic) is an enzymatic test kit for quantification of histamine in fresh fish, canned fish, fish meal, cheese, and wine. Methods: Fish products are extracted with boiling water, while cheese is extracted with water, and the extract is treated with perchloric acid/potassium hydroxyde. Wine is extracted with the reagents of RIDA® Sample Decolorant kit to eliminate color pigments and interfering compounds. The enzymatic determination is based on histamine dehydrogenase, which catalyzes the oxidative deamidation of histamine in the presence of an electron carrier that converts a dye to a color product. The resulting color intensity is directly proportional to histamine concentration and is measured at 450 nm. The substrates are coated on the microtiter plate. Results: The linear range is from 1 to 20 mg/L in the extract. LOQs are 2 mg/kg for fresh fish, canned fish, and cheese, 1.4 mg/L in wine, and 10 mg/kg for fish meal. The linear range is from 5 to 100 mg/kg for fish products and cheese, 3.6 to 72 mg/L for wine, and 25 to 500 mg/kg for fish meal. Recovery and precision are very good for all matrices, and comparisons with HPLC reference methods revealed that the method also delivers true results for fish products and wine. Agmatine shows a low side activity of around 0.75% at 10 g/kg. Possible interfering substances are ascorbic acid (more than 250 mg/L in wine or 250 mg/kg in fish). A special sample preparation to deplete ascorbic acid from fresh fish is described.

Higher fungi are a promising source of new bioactive natural products with great structural diversity, ranging from polyketides to terpenoids and alkaloids. Many of these structures are a challenge for synthetic organic chemists who have been inspired to develop new total syntheses. Nevertheless, reviews covering syntheses of fungal natural products are lacking. One aim of this review is to close this gap and to present a selection of more recent syntheses of fungal secondary metabolites from different structural classes. Secondly, this review intends to demonstrate that there are many more motivations for the synthesis of natural products than to confirm a proposed structure or to report the first total synthesis of a new natural product. Thirdly, this review is intended to stimulate the interest of organic chemists in the synthesis of fungal natural products. 1 History and Importance of (Fungal) Secondary Metabolites 2 Reasons for the Synthesis of Fungal Natural Products 3 Total Syntheses of Selected Fungal Natural Products 3.1 Terpenes 3.1.1 Sesquiterpenes 3.1.1.1 Polyquinanes 3.1.1.2 Drimanes 3.1.2 Diterpenes: Cyathanes 3.1.3 Terpenes Containing a Butenolide Moiety 3.2 Alkaloids 3.3 Natural Products Derived from the Shikimate Pathway 3.3.1 Pulvinic Acid Derivatives and Terphenyl Quinones 3.3.2 Shikimate Pathway Derived Macrolides 3.3.3 Strobilurins 3.4 Aromatic Polyketides 3.4.1 Quinones 3.4.2 Resorcylates and Catechols 3.5 Sugar Derivatives 4 Conclusion and Outlook

Open cell aluminum foam core sandwich panel structures have been proven to be of interest for protecting satellites against micrometeoroids and orbital debris (MMOD). Bumpers containing aluminum foam show outstanding capabilities to induce multiple shocks to small projectiles in the hypervelocity regime. For this work the protective performance of foam cored sandwich panels with cores made from newly developed hybrid metal foams was evaluated. Therefore shots in the hypervelocity regime on the two-stage light gas gun of the French-German Research Institute of Saint-Louis were performed. The tested targets were sandwich panels with aluminum front and rear facesheets and cores of different types of metallic foams: foams with pore densities of 10 pores per inch and 45 pores per inch were tested as pure aluminum and hybrid metallic foams. The projectiles to simulate micrometeoroids and orbital debris were aluminum spheres with a diameter of 4 mm. The impact velocity was 6500m/s. It could be shown experimentally that the nickel coating of the aluminum foams leads to a decreased crater depth in the sandwich panels. However, scatter in the coating thickness leads to variations in the foam densities of the hybrid foams, making the evaluation of the increase in the protective performance difficult. Nevertheless, due to the nickel coating the influence of the pore density seems to be more significant than reported before. By reducing the coating thickness and using high performance aluminum alloys as base material for the hybrid foams, further optimization of the protective performance could be reached. Then, the complete evaluation of the ballistic limit over a broad velocity regime should be done to see the variations in the performance of the hybrid foams over the whole velocity range being of interest for MMOD shielding technologies

Pu-erh tea originates from the province of Yunnan in south-western China. As this tea is produced by so called Aspergillus post-fermentation the question arises which molds and mycotoxins may be found in this tea. In total 36 samples of Pu-erh tea were investigated for their content of filamentous fungi and the mycotoxins aflatoxins B1, B2, G1, and G2, fumonisins B1, B2, and B3, and ochratoxin A. Fungi were isolated from all samples in a concentration of 1.0×10(1) to 2.6×10(6) colony forming units (cfu)/g tea, all together 19 fungal genera and 31 species were identified. The most prevalent species were Aspergillus acidus and Aspergillus fumigatus, followed by Zygomycetes and Penicillium species. Aflatoxins and fumonisins were not found in the samples investigated, ochratoxin A was detected in 4 of 36 teas (11.1%).

Higher fungi are a promising source of new bioactive natural products with great structural diversity, ranging from polyketides to terpenoids and alkaloids. Many of these structures are a challenge for synthetic organic chemists who have been inspired to develop new total syntheses. Nevertheless, reviews covering syntheses of fungal natural products are lacking. One aim of this review is to close this gap and to present a selection of more recent syntheses of fungal secondary metabolites from different structural classes. Secondly, this review intends to demonstrate that there are many more motivations for the synthesis of natural products than to confirm a proposed structure or to report the first total synthesis of a new natural product. Thirdly, this review is intended to stimulate the interest of organic chemists in the synthesis of fungal natural products. 1 History and Importance of (Fungal) Secondary Metabolites 2 Reasons for the Synthesis of Fungal Natural Products 3 Total Syntheses of Selected Fungal Natural Products 3.1 Terpenes 3.1.1 Sesquiterpenes 3.1.1.1 Polyquinanes 3.1.1.2 Drimanes 3.1.2 Diterpenes: Cyathanes 3.1.3 Terpenes Containing a Butenolide Moiety 3.2 Alkaloids 3.3 Natural Products Derived from the Shikimate Pathway 3.3.1 Pulvinic Acid Derivatives and Terphenyl Quinones 3.3.2 Shikimate Pathway Derived Macrolides 3.3.3 Strobilurins 3.4 Aromatic Polyketides 3.4.1 Quinones 3.4.2 Resorcylates and Catechols 3.5 Sugar Derivatives 4 Conclusion and Outlook

A commercial aflatoxin detection ELISA kit, "RIDASCREEN(®) FAST Aflatoxin", was validated with corn samples naturally contaminated with aflatoxin and non-contaminated reference corn samples according to the Japanese Notification Method ShokuAnHatsu 0816-7. The trueness, intra-laboratory repeatability, intermediate precision, limit of detection and limit of quantitation were found to be 91%, 10%, 6.4%, 0.6μg/kg and 2μg/kg, respectively, and the performance of the kit was recognized as complying with all criteria in the Supplement Table of the Notification. These data suggest that this kit is useful as a simplified device to screen out negative corn samples contaminated with less than 4μg/kg.

During the last years allergenic substances in food have gained more and more attention. Stricter rules for a peanut free food labelling demand a peanut contamination less than 5 ppm. The maintenance of a high quality of food products with regards to allergenic exposure is preferable warranted with rapid tests that can be utilized as an aid for suppliers to control raw materials, to avoid cross contamination during production and to check the final products. A rapid sandwich peanut ELISA was developed, which covers a measuring range of 2.5-20 ppm peanut (detection limit of 1.5 ppm). This test was successfully evaluated in an independent study under the supervision of the AOAC Research Institute, getting the AOAC certificate No. 030404. In-house validation and independent validation data demonstrate the reliability, accuracy and precision of the test.

An “optode,” which combines the properties of a fluorescence cuvette with those of a dialysis cell, has been tested for its applicability to continuous hormone measurement, by using thryoxine (T4) and its specific carrier, thyroxine binding globulin (TBG). The binding of T4 was monitored by measuring its quenching effect on the fluorescence of the protein.It was demonstrated that it was not feasible to carry out measurements under equilibrium conditions mainly because of the slow rate of dissociation of the TBG-T4 complex, once formed. In contrast, the values of the slope of the quench versus time graph, obtained under dynamic conditions, showed good correlation with the concentration of T4 and could, therefore, be used to measure the concentration of T4 in the sample solution. However, the utility of this method is limited by progressive saturation of the binder.

The staphylococcal enterotoxin B (SEB)-induced immediate-type skin reaction in unsensitized monkeys was used as a nonimmunologic mast cell stimulation to search for possible involvement of local neural mechanisms. Evidence is presented that substance P (SP) plays a predominant role in mediating intradermal SEB challenge in unsensitized monkeys. With a rabbit SP antiserum directed against the C-terminal region of SP, a concentration-dependent inhibition of SEB-induced skin reactivity could be demonstrated. Furthermore, a rabbit antiserum directed against the mast cell activating N-terminal part of SP was capable of impeding SEB-induced skin reactions totally. By use of SP antagonists, significant reduction of skin reactions evoked by SEB was found. Finally, capsaicin pretreatment of the skin caused a substantial inhibition of SEB-induced skin reactivity. These data suggest that SEB exerts its effect on cutaneous mast cells via stimulation of primary sensory neurons that contain SP. Moreover, a new in vivo model is described for studies of nerve-mast cell interactions.

The staphylococcal enterotoxin serotype B (SEB)-induced enteric intoxication and the immediate-type reaction in the skin of unsensitized monkeys was used to define whether agents competing with SEB for target cell receptors may inhibit pathophysiological effects. For this purpose a duodenal provocation test was developed by use of a pediatric gastroscope, allowing the evaluation of the influence of antagonists on the intestinal disorder upon SEB challenge at the same duodenal site. First, carboxymethylation of histidine residues of SEB caused a complete loss of emetic and skin-sensitizing activity without changing the immunological specificity. However, carboxymethylated SEB is a strong inhibitor of enteric intoxications and immediate-type skin reactions upon SEB challenge. Second, after immunization of BALB/c mice with monoclonal anti-SEB antibodies, monoclonal antiidiotypic antibodies (anti-Id) were obtained by the "hybridoma technique" and purification by idiotype-affinity chromatography. Anti-Id specifically inhibited the binding of horseradish peroxidase-labeled anti-SEB to the ligand, and SEB blocked as well the interaction of these two antibody species, indicating a high degree of binding-site selectivity. Anti-Id completely protected against emetic response and diarrhea upon duodenal provocation with SEB and inhibited immediate-type skin reactions as well. Further, anti-Id acted as an antagonist without triggering biologic functions themselves. This shows that anti-Id constitute a useful tool to protect against a bacterial toxin-induced intestinal disorder.