Markus Lacorn

Markus Lacorn
R-Biopharm AG · R&D

Dr. rer. nat.

About

73
Publications
13,525
Reads
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1,457
Citations
Citations since 2016
25 Research Items
568 Citations
2016201720182019202020212022020406080100120
2016201720182019202020212022020406080100120
2016201720182019202020212022020406080100120
2016201720182019202020212022020406080100120
Additional affiliations
April 2013 - present
R-Biopharm AG
Position
  • Study management and Validation Manager
April 2008 - March 2013
R-Biopharm AG
Position
  • R&D
October 1999 - March 2008
University of Hohenheim
Position
  • PostDoc Position

Publications

Publications (73)
Article
Full-text available
Background Enzytec™ Liquid Ethanol was approved as AOAC Official MethodSM 2017.07 First Action in September 2017 and is now further characterized by a collaborative study using the manual and automated version of the test. Method It is applicable to quantify ethanol in diluted or undiluted kombucha, fruit juices, vegetable juices, and alcohol-free...
Article
Full-text available
Background: Regulations in many countries worldwide prescribe that peanut must be listed on food labels as a cause of food allergies. Re-evaluated voluntary incidental trace allergen labelling (VITAL) values for peanut revealed the eliciting dose (ED01) value-at which 99% of all peanut-allergic individuals will not react-is 0.2 mg peanut protein....
Article
Full-text available
Background: The SureFast® SARS-CoV-2 PLUS Test is a reverse transcription qPCR (RT-qPCR) assay for the direct, qualitative detection of novel coronavirus (SARS-CoV-2) RNA from stainless steel environmental sample swabs. Objective: To validate the SureFast® SARS-CoV-2 PLUS Kit as part of the AOAC Research Institute's Emergency Response Validation...
Article
Full-text available
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...
Article
Full-text available
Background: Since its introduction to the analytical community, the R5 method to quantify gluten led to a strong improvement of the situation for the food industry and celiac patients. During recent years, some questions arose on the use of the Codex Alimentarius factor of two to convert from prolamins to gluten, an overestimation of rye and barley...
Article
Background: Since its introduction to the analytical community, the R5 method to quantify gluten led to a strong improvement of the situation for the food industry and celiac patients. During recent years, some questions arose on the use of the Codex Alimentarius factor of two to convert from prolamins to gluten, an overestimation of rye and barley...
Article
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...
Article
you can find the full SMPR on the AOAC web site:- http://www.aoac.org/aoac_prod_imis/AOAC_Docs/SMPRs/SMPR_2018_001.pdf
Article
EnzytecTMLiquidEthanol is an enzymatic test for the determinationof ethanol in kombucha, juices, and alcohol-free beer. The kit contains two components in a ready-to-use format. Quantification is based on the catalytic activity of alcohol dehydrogenase, which oxidizes ethanol to acetaldehyde and converts NAD+to NADH. Measurement is performed in 3 m...
Article
RIDA®QUICK Gliadin is an immuno-chromatographic test for the detection of gluten in foods, on surfaces, and in Cleaning-in-Place (CIP) waters. This test kit has been adopted as Final Action AOAC INTERNATIONALOfficial Methods of AnalysisSM2015.16for gluten in corn products. The assay is based on the monoclonal antibody R5, which recognizes gluten in...
Article
During the last decade, results from ELISA test kits have often been criticized as being flawed. Therefore, itmay appear counterintuitive that ELISAs are used for most food allergen and gluten analytical needs. One reason, in addition to the nonavailability of comparable alternative methods, is the fact that the methods used underwent a long valida...
Article
Full-text available
This article is part of the Special Section on food allergens of the Journal of AOAC International. All 25 articles are open source and you can download them free of charge. The following is the link where you can access all the articles: https://www.focos-food.com/special-section-of-the-journal-of-aoac-on-food-allergens/
Article
Full-text available
In September 2013, the AACC International (AACI) Protein Technical Committee (now Protein and Enzymes Technical Committee) initiated a collaborative study of a method for the qualitative analysis of intact gluten in processed and nonprocessed corn products, using an R5 immunochromatographic dipstick system. It was validated to demonstrate that pote...
Article
Full-text available
Specific and sensitive analytical methods are needed to guarantee the safety of gluten-free products for coeliac disease patients at the threshold of 20 mg gluten/kg. Immuno-chromatographic assays, usually available in dip-stick or lateral-flow format, provide rapid qualitative results indicating the presence or absence of gluten. In September 2015...
Article
The RIDASCREEN®FAST Milk test is a sandwich ELISA for the rapid quantification of milk proteins in various foods. The specific antibodies target casein and β-lactoglobulin. Samples are extracted and can then be analyzed in less than 40 min. The calibration curve covers a range from 2.5 to 67.5 mg/kg milk protein. The assay was validated with cookie...
Article
Full-text available
The RIDASCREEN (R) FAST Milk test is a sandwich ELISA for the rapid quantification of milk proteins in various foods. The specific antibodies target casein and beta-lactoglobulin. Samples are extracted and can then be analyzed in less than 40 min. The calibration curve covers a range from 2.5 to 67.5 mg/kg milk protein. The assay was validated with...
Article
In 2008, the AACC International Protein Technical Committee (now Protein and Enzymes Technical Committee) initiated a collaborative study of a method for determining gluten in fermented products, using an R5 competitive ELISA system. The method has been approved as AACCI Approved Method AACCI 38-55.02. The new method has been validated for testing...
Article
Full-text available
We would like to present a simple decoloration procedure for (red) wine and the subsequent enzymatic method for the specific quantification of histamine. The test kit for sample preparation contains three solutions that are used to decolorate wine by two simple precipitation steps within 15 min. The enzymatic test kit consists of a microtiter plate...
Chapter
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 f...
Article
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 Wi...
Article
In 2008, the AACC International Protein Technical Committee (now the Protein and Enzymes Technical Committee) initiated a collaborative study of a method for determining gluten in fermented products using an R5 competitive ELISA system. The method has been approved as AACCI Approved Method 38-55.01. The new method has been validated for testing fer...
Article
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 a...
Article
In 2008, the AACC International Protein Technical Committee (now the Protein and Enzymes Technical Committee) initiated a collaborative study of a method for determining gluten in selected foods using an R5 antibody sandwich ELISA system. The method has been approved as AACCI Approved Method 38-50.01. The new method has been validated for testing f...
Article
Food allergens are more or less denatured mixtures of non-defined proteins in complex matrices. The most common technique to measure these proteins is an antibody-based system as, e.g., a commercial ELISA system which consists of an extraction procedure, suitable antibodies and a calibrator. Until now, only a few attempts to standardize these diffe...
Article
Methods are needed for detecting allergenic proteins in wine after fining processes, both for legal requirements and to estimate any risk for allergic individuals. One of the critical allergens in this case is the protein fraction from egg white. The efficacy of use of a commercial egg protein detection kit was evaluated using wines spiked with egg...
Article
Carbohydrates, which were not digested in the jejunum, will be fermented by micro-organisms to short chain fatty acids. These are transported by the monocarboxylate transporter 1 (MCT1) through the gut wall and serve as fuels for colonic cells. To deliver butyrate to the distal part of the intestine, inulin with a low precaecal digestibility was ch...
Article
Sexual differentiation in Placentalia consists of several consecutive steps during fetal, postnatal, and premature development. It is known from male rats that an elevation in testosterone synthesis is observable within 2 d of birth, which leads to a male pattern of growth hormone (GH) secretion with low base levels and high amplitudes compared wit...
Article
An overview is given of sensitization and allergic reaction on food, along with minimal eliciting doses for selected allergens (milk, egg, peanut), followed by the legislative situation in the European Community, the USA, Canada, Australia/New Zealand and Japan. The main focus of the paper discusses methods for food allergen determination (chromato...
Article
Immunocastration of boars leads to a maintenance of growth harmone (GH) and a loss of anabolic hormones [androgens, oestrogens, insulin-like growth factor (IGF-I)] but an increase of voluntary feed intake. The aim of the experiment was to clarify whether IGF-I is increased by increasing feed supply in immunocastrated boars leading to improved anabo...
Article
Androstenone (5α-androst-16-en-3-one) is a volatile steroid which is synthesized in boar testes and stored in high amounts in fat thus leading to an urine-like odor in pork. Whereas microtiter assays (MTA) exist for fat determination, measurement in blood with MTA was not yet possible. The system reported here is based on a specific antiserum and a...
Article
Full-text available
Surgically castrated male piglets (barrows) reveal an increase in LH and a decrease in GH compared to untreated boars. Boars that were castrated by immunization against gonadotropin releasing hormone (GnRH) have decreased LH but maintain GH. The difference in GH levels between barrows and immunological castrated boars cannot be explained by testicu...
Article
Bioassay directed extraction and purification of mango peels revealed the 5-(11'Z-heptadecenyl)-resorcinol (1) and the known 5-(8'Z,11'Z-heptadecadienyl)-resorcinol (2) previously not described in Mangifera indica L. The structures of both compounds were determined by extensive 1D and 2D NMR studies and MS. Both compounds exhibited potent cyclooxyg...
Article
11beta-Hydroxysteroid-dehydrogenase 2 (11beta-HSD2) activity occurs in boar testes but it is not known which cell types express 11beta-HSD2 mRNA and protein. Therefore, testes samples were taken from mature boars. For immunocytochemistry and Western blot pig-specific antibodies were raised against a 10-amino acid peptide corresponding to amino acid...
Article
Immunization of boars against GnRH inhibits synthesis of testicular steroids including androstenone (sex odour). Timing of the second vaccination (anamnestic reaction) should occur as late as possible to maintain anabolic effects of testicular hormones, but early enough to remove androstenone from body fat. Five catheterized boars received the seco...
Article
Application of endogenous anabolic steroids to meat producing animals is not allowed in the EU. In other countries application is practised due to a low oral activity based on an efficient first liver passage. This contrasts with pharmacological investigations where steroids were readily absorbed by the buccal and sublingual mucosa using absorption...
Article
Skatole originates from microbial processing of tryptophan in the large intestine of pigs and accumulates in adipose tissue. Formation may be inhibited by the anti-apoptotic function of butyrate formed out of raw potato starch. Two groups of pigs (each consisting of gilts and barrows) were fed from 30 to 110 kg life weight either a conventional die...
Article
17beta-estradiol (E2) concentrations are in the low pg/ml range in plasma. To develop a sensitive enzyme immunoassay (EIA) for E2-determination a highly specific antibody raised against a 6-carboxymethyl (CMO)-E2-bovine serum albumine conjugate was used. Based on 6-CMO-E2 and 6-amino-E2, four biotinylated tracers with two different spacer lengths b...
Article
Sampling of odor substances in the emissions from swine production facilities is still the limiting step for routine odor quantification. Solid sorption techniques based on cartridges were developed for three categories of substances (indoles, volatile fatty acids and methylthiol) and were standardized to a sampling time of 15 min. These cartridges...
Article
Many single effects of glucocorticoids are known but complex metabolic reactions in pigs in response to a glucocorticoid challenge were not reported. Seven pigs (mean weight 69 kg) with indwelling catheters were kept in metabolic crates. After a 7-day control period they were fed for 9 days with 0.4 mg dexamethasone (dex) per kg body weight daily,...
Article
Evidence exists that butyrate inhibits apoptosis of colon crypt cells in vivo so that less tryptophan from cell debris is available for skatole formation by microbes in the pig colon. In this study, potato starch containing a high proportion of resistant starch was fed to test the hypothesis that increased butyrate formation will occur in the colon...
Article
The present study was undertaken to investigate the influence of natural and anthropogenic stressors on the induction of apoptosis, metallothionein (MT) isoforms, heat shock proteins and DNA strand breaks in the marine flatfish dab (Limbanda limanda) Seasonal changes and possible physiological influences were evaluated over a 1-year period at a fix...
Article
Full-text available
11beta-Hydroxysteroid dehydrogenase 2 (11beta-HSD 2) converts active cortisol to inactive cortisone and thus modifies the availability of glucocorticoids for the target tissue. An additional function is the protection of the aldosterone receptor in mineralocorticoid-sensitive tissues such as the kidney and the gut. The occurrence of 11beta-HSD 2 ac...
Article
A rapid, reproducible, and sensitive ion-exchange chromatography (IEC) method combined with graphite-furnace atomic absorption spectrometry (GF-AAS) was developed to separate and quantify basal amounts of both metallothionein (MT) isoforms in dab (Limanda limanda) liver samples. Dab liver homogenates were saturated with Cd, and obtained cytosols we...
Chapter
The cyclic ovarian activity in sheep and goats of most breeds is limited to autumn and winter (Shelton, 1960; Claus et al., 1985; Martin et al., 1986). The photoperiod is the main environmental factor regulating the ovarian activity so that the decreasing daylength stimulates the slow onset of cyclicity in autumn (Legan and Karsch, 1980; Mori et al...
Article
Full-text available
During the last few years sponges have been proven to be suitable model organisms for biomonitoring programmes. Previously it was reported that the marine sponge Suberites domuncula reacts to cadmium, both under controlled laboratory conditions and in the field with an increased expression of the heat-shock protein 70 and with DNA damage. In this s...
Article
Apoptosis, also known as programmed cell death, is a physiological and irreversible process in tissue homeostasis that leads to DNA fragmentation of multiples of 180-200 bp. Because apoptosis can be initiated not only by physiological stimuli but also by various chemical substances, the present paper investigates the suitability of apoptosis as a b...
Article
Full-text available
The marine sponge Suberites domuncula was used as a bioindicator to study the effects of cadmium on the occurrence of DNA strand breakage and on the induction of the expression of the stress biomarkers, heat shock protein 70 (HSP70) and glucose-regulated protein 78 (GRP78) homolog. The cDNA encoding GRP78 homolog from S. domuncula was isolated and...
Article
The effects of different polychlorinated biphenyls (PCBs) including toxic coplanar non-ortho (PCB77) and non-planar mono-ortho (PCB118) and di-ortho (PCB153) congeners on the extent of DNA damage as well as on the expression of heat shock protein 70 (HSP70) were investigated in the marine sponge Suberites domuncula Olivi (Porifera; Demospongiae). A...
Article
Full-text available
The marine sponge Suberites domuncula (Porifera; Demospongiae) was used in a natural field study (in the vicinity of Rovinj, Croatia) as a bioindicator to assess the genotoxic risk of cadmium exposure for sponges as a model for invertebrates, and as an early stress marker of expression of heat-shock protein 70 (M, 73 kDa; termed HSP73). Significant...
Article
The marine demosponge Suberites domuncula is abundantly present on muddy sand bottoms, both in the open sea and in harbors. In the present study it is shown that exposure of S. domuncula to cadmium (CdCl2) in concentrations ranging from 0.01 to 5.0 g ml−1 for up to 5 d results in apoptotic fragmentation of DNA. Kinetics experiments revealed that af...
Article
The natural occurrence of the sex steroid hormones progesterone, testosterone, 17β-estradiol and estrone in food was investigated in a survey of the German market basket. The main metabolic precursors, intermediates and metabolites (pregnenolone, androstenedione, hydroxyprogesterone, dehydroepiandrosterone (DHEA), dihydrotestosterone, androsterone,...

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