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Methods are needed for detecting allergenic proteins in wine after fining processes, both for legal requirements and to estimate any risk for allergic individuals. Two of the critical allergens in this case are the protein fraction from egg white and caseins. Requirements for methods were set up both by the International Organisation of Vine and Wine (OIV) and the European Commission and included collaborative tests to determine repeatability, reproducibility, limit of detection (LOD), and recovery. Two collaborative tests with 18 participants from all over the world were conducted using commercial enzyme-linked immunosorbent assay kits to quantify egg white protein and casein. For each analyte, nine red and white wines (RW and WW, respectively) with different analyte concentrations were prepared and sent to the participants. Resulting sets of data were analyzed according to the AOAC by eliminating outliers and calculating the performance statistics for each assay. For wines with no or very low analyte concentrations, the values were extrapolated from the calibration curve and the resulting LODs are in accordance with the performance criteria set by the OIV method OIV-MA-AS315-23: R2012. For casein in WW and egg white protein in RW, all Horwitz ratio values for samples with concentrations above the required limit of quantification (0.5 mg/L) were below 2. While the recovery of egg white protein from RW is 90 % or more, the recovery of casein from WW is between 73 and 76 %, which is attributable to the instability/solubility of casein in wine.

Allergens cannot at present be measured with the trueness that attends the analysis of well-characterized chemical entities such as mycotoxins where the analytes are defined and identical in sample and calibrator. By nature, allergens are nearly always a mixture of different proteins with different mass fractions of each single protein. Allergens are furthermore in a commodity with different total protein contents in the presence of an unknown matrix. To circumvent these difficulties, reference materials for allergens would be useful but until now not realized due to biological variabilities of the materials, and the contradiction between medical issues and declaration of foods due to legislation. Examples for standardization efforts are given which are (1) peanut where a common reference material not intended for allergen determination is used and (2) gluten/gliadin where the extraction procedure, the antibody and a calibrator are standardized but proficiency tests are not fit-for-purpose due to inhomogeneity of the testing material. Furthermore, the analytical minimum requirements and the declaration of egg-white proteins, caseins and lysozyme in wine are reviewed. To show one negative example for standardization efforts, milk is discussed. The possibilities and limits of reference materials for the standardization of allergen determinations are discussed.

The development of an indirect competitive enzyme-immunoassay for the detection of hidden hazelnut protein in complex food matrices is described. A sensitive and selective polyclonal antibody was raised by immunisation of laying hens with protein extracts from roasted hazelnuts. In contrast to traditional antibody generation in mammals, the antibody was not isolated from the blood of immunised mammals but from the egg yolk of immunised chickens. A standard calibration curve was optimised using immunoaffinity purified antibody extract and a coating antigen concentration of 10 μg ml −1 . One percent skim milk powder was chosen for blocking. The assay has a minimum detection limit of 10 μg l −1 , with an IC 50 of 618 μg l −1 when a 50 mM phosphate buffer at pH 7.5 and 10 mM sodium chloride is used as assay buffer. The cross reactivity testing shows a high specificity for hazelnut proteins and various foods and food additives were found to be non reactive except beans, sunflower seed or poppy seed.

Enzyme-linked immunosorbent assays (ELISA) are effective methods for the determination of antigens in defined matrices. The method is routinely used today in clinical chemistry as well as in food analysis. It offers the possibility to measure small amounts of analytes like mycotoxins, pesticides and vitamins as well as food allergens in different food matrices. This chapter discusses key terms of the method and the main components which are required. Furthermore, it describes possible extraction procedures of the measurands from food. Finally, quality parameters for the method are discussed.

A dessert matrix previously used for diagnosis of food allergies was incurred with pasteurised egg white or skimmed milk powder at 3, 6, 15 and 30 mg allergen protein per kg of dessert matrix and evaluated as a quality control material for allergen analysis in a multi-laboratory trial. Analysis was performed by immunoassay using five kits each for egg and milk (based on casein) and six 'other' milk kits (five based on β-lactoglobulin and one total milk). All kits detected allergen protein at the 3 mg kg(-1) level. Based on ISO criteria only one egg kit accurately determined egg protein at 3 mg kg(-1) (p=0.62) and one milk (casein) kit accurately determined milk at 6 (p=0.54) and 15 mg kg(-1) (p=0.83), against the target value. The milk "other" kits performed least well of all the kits assessed, giving the least precise analyses. The incurred dessert material had the characteristics required for a quality control material for allergen analysis.

During the EU-funded project Allergentest (QLK1-CT-2001-01151) a survey for the presence of hidden proteins of hazelnut and peanut in suspected pre-packed foodstuffs within EC member states was carried out to check the usefulness of the developed rapid test-kits. There were 11 participating countries in this study: Belgium, Portugal, Italy, Spain, France, United Kingdom, Slovenia, Greece, Norway, Czech Republic, and Austria. Each country submitted between 35-40 food samples. All foodstuffs were tested using the two test kits developed within the EC-project. The results presented were quantitative for the ELISA and qualitative for the LFD method (meaning positive or negative results - presence or absence) for peanut and hazelnut. The results were compared with the information given on the labels. Although at the time of the survey the new European Labelling directive (2003/89/EC) for allergens was not in force, the comparison showed whether the labelling was sufficient or not and where problems occured

A tetradecapeptide with the proposed structure of growth hormone release inhibiting factor was synthesized by a classical fragment approach.

A shortened 23 amino acid analog (dextronatrin) of rat ANP(1–28) in which, in position 6 next to Cys, there is a D-Tyr residue, has been compared to rat ANP(1–28) for its diuretic and electrolyte-excreting properties in male normotensive rats. Both compounds elicited an equally large but short-lasting diuresis. The natriuresis was also short-lasting as were the changes in Cl− and K+ excretion. In a rabbit aortic strip preparation dextronatrin antagonized the vasoconstricting effects of noradrenaline but to a lesser extent than rat ANP(1–28).

Addition of increasing doses of synthetic growth hormone-release inhibiting hormone (GH-RIH) leads to a progressive decrease of the basal and N 6 monobutyryl cyclic AMP-,theophylline- and prostaglandin E 2 -induced release of immunoreactive growth hormone (GH) and thyrotropin (TSH) release from rat anterior pituitary cells in monolayer culture. A halfmaximal effect is measured at 3 × 10 −9 M GH-RIH while a maximal inhibition to 10–20% of the control level is found at 1 × 10 −7 M. Using rat hemipituitaries and measurement of GH release by both polyacrylamide gel electrophoresis and radioimmunoassay, a maximal effect of GH-RIH was found in the first 5 min of incubation. The inhibitory effect of GH-RIH on GH release remained constant for at least 3 h. GH-RIH does not affect the basal or induced release of prolactin and luteinizing hormone nor the high K + -induced release of GH and TSH.

Since cyclic peptides constitute a group of natural and synthetic products of considerable practical and theoretical significance, model experiments were carried out to explore the scope of the four component condensation for the synthesis of these structures.

Summary 1 × 10 −7 M growth hormone-release inhibiting hormone (GH-RIH or somatostatin) leads to a 50% inhibition of adenosine 3′,5′-monophosphate (cyclic AMP) accumulation in anterior pituitary tissue during the first 2 min of incubation. This lowering of cyclic AMP levels is accompanied by inhibition of the release of immunoreactive growth hormone and thyrotropin. GH-RIH has also a marked inhibitory effect on the theophyline- and prostaglandin E 2 -induced accumulation of adenohypophyseal cyclic AMP.

Since modified peptides embodying a 1,1-disubstituted hydrazide (II) have not been described previously, model experiments were carried out to determine suitable reaction conditions for their preparation. The synthesis of model compounds of type II is the subject of this paper.

Die geschutzten Tripeptide 5a, 5b, 16a und 16b, welche N-Dimethylamino-ξ-valin oder N-Dimethylamino-DL-leucin. als unnaturliche Bausteine enthalten, wurden mittels einer Ugi-Reaktion synthetisiert und zu Analogen der Eledoisinteilsequenz 1 aufgebaut. Die Stabilitat gegenuber α-Chymotrypsin und die blutdrucksenkende Wirkung von 1, 12a, 12b, 20a und 20b wurden verglichen. Application of the Ugi Reaction in the Synthesis of Modified Partial Sequences of Eledoisin The protected tripeptides 5a, 5b, 16a, and 16b containing N-dimethylamino-ξ-valine or N-dimethylamino-DL-leucine. as unnatural building blocks were synthesized using an Ugi reaction. They were elaborated into analogs of 1, a partial sequence of eledoisin. The stability towards α-chymotrypsin and the blood pressure lowering activity of 1, 12a, 12b, 20a, and 20b were compared.

The PGE2-induced cyclic AMP accumulation in the rat anterior pituitary in vitro is inhibited by [desamino1]-[desamino1] [descarboxy14]- and [D-Lys4]-somatostatin similarly to somatostatin, while the [descarboxy14]-somatostatin exhibits reduced activity; [D-Lys9]-somatostatin is ineffective at a higher concentration.

In 28 patients with non-seminomatous testicle tumour the tumour markers human chorionic gonadotropin (HCG) and alpha-fetoprotein (AFP) were determined radioimmunologically and enzymeimmunologically, respectively. While tumours with chorionic carcinoma (n = 8) always were marker-positive, in the embryonic carcinoma in 2 out of 10 cases falsely negative findings appeared. On 5 patients the biochemical monitoring of the course of the testicle tumour disease is demonstrated in detail by means of HCG and AFP and estimated as very helpful method. Advantages and problems of the marker diagnostics are shown and discussed. The positive marker findings were absolutely evident for a metastasation. On the other hand, marker negativation was not always to be equated with absence of a tumour and demanded a further control of the patient by means of all other available methods of diagnostics up to the second-look-operation.

Analogues of melanocyte stimulating hormone/release inhibiting hormone (MIF), H-Pro-N-isobutyl-Gly-Gly-NH2, H-Pro-MeLeu-Gly-NH2 (L,L) and H-Pro-MeLeu-Gly-NH2 (L,D) were synthesized by the four-component condensation (4 CC). In addition compounds H-Pro-MeLeu-Ala-NH2 (L,L,D) and H-Pro-MeLeu-Ala-NH2 (L,D,D) were prepared by classical methods.