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1.
Meat Sci ; 213: 109497, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38508078

RESUMEN

Mainly skatole and androstenone have so far been considered causative for boar taint. Using a mixed methods approach it is shown herein that 2-aminoacetophenone (AAP) affects human perception of pork, too. We explored the importance of AAP in four trials: (1) chemical analyses of 221 fat samples from boar carcasses revealed that AAP occurs, on average, in similar quantities as skatole while the levels of androstenone being four-fold. (2) ranking tests with mixtures of androstenone and/or skatole with AAP presented on smell strips to trained sensory assessors showed that AAP amplifies boar odour. In order to study AAP's importance in meat products, four experimental variants of Lyon type sausage were then produced: a control, a product with added skatole (0.075 µg/g fat tissue), with added AAP (0.075 µg/g fat tissue), and with addition of both compounds. (3) results of a consumer discrimination test panel (n = 71) showed that, when added to a sausage system, APP causes a sensory difference of similar size as skatole while the methodology chosen affects the effect size: tetrad tests proved to be more sensitive than duo trio difference tests, in the tetrad test a sensory difference expressed as d' (d-prime) of 1.0 was reached. (4) a hedonic consumer test (n = 121) finally revealed that APP decreased consumer liking of the APP-spiked sausage - even to a stronger extent than skatole. APP caused significant drops in smell, taste, mouth-feel, after-taste and overall liking in Lyoner. Overall the findings suggest that, in the context of pork meat, AAP is of similar olfactory importance as skatole.


Asunto(s)
Acetofenonas , Comportamiento del Consumidor , Productos de la Carne , Odorantes , Escatol , Animales , Productos de la Carne/análisis , Humanos , Escatol/análisis , Odorantes/análisis , Masculino , Adulto , Femenino , Porcinos , Persona de Mediana Edad , Acetofenonas/análisis , Gusto , Adulto Joven , Androsterona/análisis , Olfato , Androstenos/análisis
2.
Drug Test Anal ; 13(11-12): 1835-1851, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34648228

RESUMEN

The testing strategy for the detection of testosterone (T) or T-prohormones is based on the longitudinal evaluation of urinary steroid concentrations accompanied by subsequent isotope ratio mass spectrometry (IRMS)-based confirmation of samples showing atypical concentrations or concentration ratios. In recent years, the IRMS methodology focussed more and more on T itself and on the metabolites of T, 5α- and 5ß-androstanediol. These target analytes showed the best sensitivity and retrospectivity, but their use has occasionally been challenging due to their comparably low urinary concentrations. Conversely, the carbon isotope ratios (CIR) of the main urinary metabolites of T, androsterone (A) and etiocholanolone (EITO), can readily be measured even from low urine volumes; those however, commonly offer a lower sensitivity and shorter retrospectivity in uncovering T misuse. Within this study, the CIRs of A and ETIO were combined with their urinary concentrations, resulting in a single parameter referred to as 'difference from weighted mean' (DWM). Both glucuronidated and sulfated steroids were investigated, encompassing a reference population (n = 110), longitudinal studies on three individuals, influence of ethanol in two individuals, and re-analysis of several administration studies including T, dihydrotestosterone, androstenedione, epiandrosterone, dehydroepiandrosterone, and T-gel. Especially DWM calculated for the sulfoconjugated steroids significantly prolonged the detection time of steroid hormone administrations when individual reference ranges were applied. Administration studies employing T encompassing CIR common for Europe (-23.8‰ and -24.4‰) were investigated and, even though for a significantly shorter time period and less pronounced, DWM could demonstrate the exogenous source of T metabolites.


Asunto(s)
Androsterona/análisis , Etiocolanolona/análisis , Congéneres de la Testosterona/análisis , Testosterona/análisis , Androsterona/orina , Isótopos de Carbono , Doping en los Deportes/prevención & control , Etanol/administración & dosificación , Etanol/farmacología , Etiocolanolona/orina , Femenino , Humanos , Estudios Longitudinales , Masculino , Espectrometría de Masas/métodos , Persona de Mediana Edad , Detección de Abuso de Sustancias/métodos , Testosterona/orina , Congéneres de la Testosterona/orina
3.
Drug Test Anal ; 13(11-12): 1822-1834, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33942526

RESUMEN

Intact phase II steroid metabolites have poor product ion mass spectra under collision-induced dissociation (CID) conditions. Therefore, we present herein the liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/(MS)) behavior of intact phase II metabolites of oxosteroids after derivatization. Based on the fact that Girard's reagent T (GRT), as derivatization reagent, was both convenient and efficient in terms of the enhancement in the ionization efficiency and the production of diagnostic product ions related to the steroid moiety, the latter was preferably selected between methoxamine and hydroxylamine upon the model compounds of androsterone glucuronide and androsterone sulfate. Sixteen different glucuronides and 29 sulfate conjugated metabolites of anabolic androgenic steroids (AASs), available either as pure reference materials or synthesized/extracted from administration studies, were derivatized with GRT, and their product ion spectra are presented. Product ion spectra include in all cases high number of product ions that in some cases are characteristic for certain structures of the steroid backbone. More specifically, preliminary results have shown major differences in fragmentation pattern for 17α/17ß-isomers of the sulfate conjugates, but limited differentiation for 17α/17ß-isomers of glucuronide conjugates and for 3α/3ß- and 5α/5ß-stereoisomers of both sulfate and glucuronide conjugates. Further to the suggestion of the current work, application on mesterolone administration studies confirmed-according to the World Anti-Doping Agency (WADA) TD2015IDCR-the presence of seven intact phase II metabolites, one glucuronide and six sulfates with use of LC-ESI-MS/(MS).


Asunto(s)
Anabolizantes/análisis , Androsterona/análogos & derivados , Doping en los Deportes/prevención & control , Mesterolona/análisis , Anabolizantes/química , Androsterona/análisis , Androsterona/química , Betaína/análogos & derivados , Betaína/química , Cromatografía Liquida/métodos , Humanos , Mesterolona/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos
4.
Int J Mol Sci ; 22(2)2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33418978

RESUMEN

The peripheral zone (PZ) and transition zone (TZ) represent about 70% of the human prostate gland with each zone having differential ability to develop prostate cancer. Androgens and their receptor are the primary driving cause of prostate cancer growth and eventually castration-resistant prostate cancer (CRPC). De novo steroidogenesis has been identified as a key mechanism that develops during CRPC. Currently, there is very limited information available on human prostate tissue steroidogenesis. The purpose of the present study was to investigate steroid metabolism in human prostate cancer tissues with comparison between PZ and TZ. Human prostate cancer tumors were procured from the patients who underwent radical prostatectomy without any neoadjuvant therapy. Human prostate homogenates were used to quantify steroid levels intrinsically present in the tissues as well as formed after incubation with 2 µg/mL of 17-hydroxypregnenolone (17-OH-pregnenolone) or progesterone. A Waters Acquity ultraperformance liquid chromatography coupled to a Quattro Premier XE tandem quadrupole mass spectrometer using a C18 column was used to measure thirteen steroids from the classical and backdoor steroidogenesis pathways. The intrinsic prostate tissue steroid levels were similar between PZ and TZ with dehydroepiandrosterone (DHEA), dihydrotestosterone (DHT), pregnenolone and 17-OH-pregnenolone levels higher than the other steroids measured. Interestingly, 5-pregnan-3,20-dione, 5-pregnan-3-ol-20-one, and 5-pregnan-17-ol-3,20-dione formation was significantly higher in both the zones of prostate tissues, whereas, androstenedione, testosterone, DHT, and progesterone levels were significantly lower after 60 min incubation compared to the 0 min control incubations. The incubations with progesterone had a similar outcome with 5-pregnan-3,20-dione and 5-pregnan-3-ol-20-one levels were elevated and the levels of DHT were lower in both PZ and TZ tissues. The net changes in steroid formation after the incubation were more observable with 17-OH-pregnenolone than with progesterone. In our knowledge, this is the first report of comprehensive analyses of intrinsic prostate tissue steroids and precursor-driven steroid metabolism using a sensitive liquid chromatography-mass spectrometry assay. In summary, the PZ and TZ of human prostate exhibited similar steroidogenic ability with distinction in the manner each zone utilizes the steroid precursors to divert the activity towards backdoor pathway through a complex matrix of steroidogenic mechanisms.


Asunto(s)
Neoplasias de la Próstata/patología , Esteroides/metabolismo , Androstenodiona/análisis , Androsterona/análisis , Cromatografía Líquida de Alta Presión , Humanos , Masculino , Espectrometría de Masas , Progesterona/análogos & derivados , Progesterona/análisis , Progesterona/metabolismo , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Esteroides/análisis , Esteroides/química , Testosterona/análisis
5.
Drug Test Anal ; 13(4): 770-784, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33242373

RESUMEN

The detection of 19-norsteroids abuse in doping controls currently relies on the determination of 19-norandrosterone (19-NA) by gas chromatography-tandem mass spectrometry (GC-MS/MS). An additional confirmatory analysis by gas chromatography coupled to isotope ratio mass spectrometry (GC-C-IRMS) is performed on samples showing 19-NA concentrations between 2.5 and 15 ng/ml and not originated from pregnant female athletes or female treated with 19-norethisterone. 19-Noretiocholanolone (19-NE) is typically produced to a lesser extent as a secondary metabolite. The aim of this work was to improve the GC-C-IRMS confirmation procedure for the detection of 19-norsteroids misuse. Both 19-NA and 19-NE were analyzed as target compounds (TCs), whereas androsterone (A), pregnanediol (PD), and pregnanetriol (PT) were selected as endogenous reference compounds (ERCs). The method was validated and applied to urine samples collected by three male volunteers after the administration of nandrolone-based formulations. Before the instrumental analysis, urine samples (<25 ml) were hydrolyzed with ß-glucuronidase from Escherichia coli and extracted with n-pentane. Compounds of interest were purified through a single (for PT) or double (for 19-NE, 19-NA, A, and PD) liquid chromatographic step, to reduce the background noise and eliminate interferences that could have affect the accuracy of δ13 C values. The limit of quantification (LOQ) of 2 ng/ml was ensured for both 19-NA and 19-NE. The 19-NE determination could be helpful in case of "unstable" urine samples, in late excretion phases or when coadministration with 5α-reductase inhibitors occur.


Asunto(s)
Doping en los Deportes/prevención & control , Estranos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Detección de Abuso de Sustancias/métodos , Adulto , Androsterona/análisis , Femenino , Humanos , Límite de Detección , Masculino , Persona de Mediana Edad , Nandrolona/administración & dosificación , Nandrolona/metabolismo , Pregnanodiol/análisis , Pregnanotriol/análisis
6.
J Pharmacol Toxicol Methods ; 106: 106938, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33080389

RESUMEN

BACKGROUND: Urinary sulfate fraction of the anabolic androgenic steroids is not analyzed routinely in anti-doping analyses but has demonstrated in the last years an increasing interest among the anti-doping community. Sulfate conjugates are linked to plasma proteins increasing the residence time in the body compared to glucuro-conjugated metabolites, and then their analyses may allow improving the detection time window of specific metabolites. Hydrolysis of sulfates can be made enzymatically or chemically and can be challenging, depending on the strategy selected. METHODS: Hydrolysis by solvolysis was validated for metabolic studies, focusing on setting a quality control able to assess the hydrolytic step. To the internal standards mixture, androsterone-D4 and etiocholanolone-D5 sulfate were added. The proposed protocol was applied over samples collected after dehydroepiandrosterone (DHEA) administrations. RESULTS: The stability of the structures showed good results, and no evident formation of degradation products was observed. Internal standard to monitor the efficiency of hydrolysis, recovery, and retention time was successfully introduced. Additional analytes (4ß-hydroxy-DHEA, 5-androstene-3ß,17ß-diol and 5α-androstane-3ß,17ß-diol) were found to be affected besides of DHEA and epiandrosterone (epiA) as previously described. CONCLUSIONS: Results in terms of linearity, precision, and accuracy, showed that the method is suitable to quantify seven analytes in urine in the sulfated fraction. The validated method was successfully applied to urine samples after administration of DHEA to detect this compound in the sulfate fraction and preliminarily to negative samples from athletes of both sexes, to determine Q1 and Q3 inter-quartiles. A quality control assessment for the hydrolysis efficiency was established for every individual sample.


Asunto(s)
Sulfato de Deshidroepiandrosterona/análisis , Doping en los Deportes/prevención & control , Detección de Abuso de Sustancias/métodos , Administración Oral , Adulto , Androsterona/análogos & derivados , Androsterona/análisis , Androsterona/química , Androsterona/orina , Sulfato de Deshidroepiandrosterona/administración & dosificación , Sulfato de Deshidroepiandrosterona/química , Sulfato de Deshidroepiandrosterona/orina , Etiocolanolona/análisis , Etiocolanolona/química , Etiocolanolona/orina , Femenino , Cromatografía de Gases y Espectrometría de Masas , Voluntarios Sanos , Humanos , Hidrólisis , Masculino , Persona de Mediana Edad , Estándares de Referencia
7.
Drug Test Anal ; 12(11-12): 1554-1560, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32697436

RESUMEN

Identification and evaluation of long-term markers is crucial in prolonging the detection window for anabolic steroid abuse in sport. Recently, sulfoconjugated epiandrosterone was identified as a potential long-term marker for the abuse of certain endogenous anabolic agents, including testosterone, which continues to be widely used as a performance enhancing agent in sport. To evaluate the applicability of epiandrosterone sulfate as a marker for testosterone use, administration studies were conducted with multiple modes of testosterone administration - transdermal, intramuscular, and subcutaneous. A modified sample preparation method was used to collect both glucuronidated and sulfoconjugated analytes of interest. Carbon isotope ratio measurements from the administration studies are presented here. Epiandrosterone was less effective than the conventionally used target compounds for detection of the low dose application (transdermal gel). With intramuscular administration, epiandrosterone was more diagnostic than with transdermal administration, but it did not prolong the detection window more than the conventional target compounds. With subcutaneous administration, the doses administered to the subjects were varied and the effect on the epiandrosterone values was dependent on the magnitude of the dose administered. Epiandrosterone does not appear to be a useful marker in the detection of low dose testosterone administration. It is responsive to higher dose administration, but it does not provide an extension of the detection window relative to conventional target compounds.


Asunto(s)
Anabolizantes/administración & dosificación , Anabolizantes/metabolismo , Androsterona/metabolismo , Detección de Abuso de Sustancias/normas , Testosterona/administración & dosificación , Testosterona/metabolismo , Administración Cutánea , Adulto , Anabolizantes/análisis , Androsterona/análisis , Biomarcadores/metabolismo , Doping en los Deportes/métodos , Doping en los Deportes/prevención & control , Cromatografía de Gases y Espectrometría de Masas/métodos , Cromatografía de Gases y Espectrometría de Masas/normas , Geles , Humanos , Inyecciones Intramusculares , Inyecciones Subcutáneas , Absorción Intramuscular/efectos de los fármacos , Absorción Intramuscular/fisiología , Masculino , Absorción Cutánea/efectos de los fármacos , Absorción Cutánea/fisiología , Absorción Subcutánea/efectos de los fármacos , Absorción Subcutánea/fisiología , Detección de Abuso de Sustancias/métodos , Testosterona/análisis
8.
Chemosphere ; 237: 124371, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31369902

RESUMEN

Public concerns about potential ecological risks of androgens discharged to the environment through wastewater treatment plants (WWTPs) has resulted in an increased interest regarding the occurrence and fate of androgens in WWTPs. In this study, the occurrence and removal of eight androgens from 12 municipal WWTPs distributed in eleven cities in China were investigated. The composition profiles of eight androgens in influent, effluent, and excess sludge were studied. Multiple factor analyses were performed to reveal the factors affecting the distribution of androgens in WWTP influent. Results showed similar composition profiles of androgens in the studied WWTPs, with androsterone and dehydroepiandrosterone confirmed as the dominant androgens. The distributions of androgens in WWTP influent were related to the chemical oxygen demand in influent and the gross domestic product (GDP) of WWTP-associated cities. The target androgens have high aqueous removal rates, with a mean removal rate of >90%. Additionally, the behaviors of androgens were evaluated by mass balance along anaerobic-anoxic-oxic (AAO) processes in a WWTP, in which many of the androgens were eliminated mainly in the anaerobic tank. Further, 15 biotransformation products of testosterone were identified under anaerobic, anoxic, and aerobic sludge, respectively. Based on these metabolites, a general biotransformation pathway of testosterone under anaerobic, anoxic, and aerobic sludge is presented.


Asunto(s)
Andrógenos/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Andrógenos/metabolismo , Androsterona/análisis , China , Ciudades , Aguas del Alcantarillado/química , Testosterona/metabolismo , Instalaciones de Eliminación de Residuos , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua
9.
Meat Sci ; 152: 65-72, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30826630

RESUMEN

While forming mixtures is a widely used approach for other raw materials in food industry, it has not yet been systematically analyzed for boar tainted meat. That is why we simultaneously studied four factors relevant for the production of emulsion-type sausages: percentage boar meat (skatole concentrations up to 0.3 µg/g, androstenone up to 3.8 µg/g in melted backfat), duration of traditional smoke and concentration levels of two spices. 16 variants of Frankfurters were produced in two independent studies and evaluated by in total 211 consumers. A linear mixed effects model revealed that increased levels of boar tainted meat significantly reduced consumer acceptance which could not be compensated by increased smoke or spice levels. We propose a non-inferiority test to identify the mixture which is similarly accepted as the reference made without boar tainted meat. Up to 33% tainted boar meat is proposed, assuming a liking drop of 0.5 on a 9 point liking scale as benchmark for an inferior product.


Asunto(s)
Manipulación de Alimentos/métodos , Productos de la Carne/normas , Gusto , Tejido Adiposo/química , Adolescente , Adulto , Anciano , Androsterona/análisis , Animales , Comportamiento del Consumidor , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escatol/análisis , Porcinos
10.
J Steroid Biochem Mol Biol ; 185: 47-56, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30031148

RESUMEN

Growth and development of an embryo or fetus during human pregnancy mainly depend on intact hormone biosynthesis and metabolism in maternal amniotic fluid (AF). We investigated the hormonal milieu in AF and developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of 14 sulfated and 6 unconjugated steroids in AF. 65 A F samples (male: female = 35: 30) of mid-gestation ranging from 16th week of gestation to 25th week of gestation were analyzed. Reference data of 20 steroid levels in AF of healthy women were provided. 13 sulfated and 3 unconjugated steroids were for the first time quantified in AF by LC-MS/MS. Highest concentrations were found for pregnenolone sulfate (PregS: mean ±â€¯SD, 8.6 ±â€¯3.7 ng/mL), 17α-hydroxypregnenolone sulfate (17OHPregS: 4.9 ±â€¯2.0 ng/mL), epitestosterone sulfate (eTS: 7.3 ±â€¯3.6 ng/mL), 16α-hydroxydehydroepiandrosterone sulfate (16OH-DHEAS: 21.5 ±â€¯10.7 ng/mL), androsterone sulfate (AnS: 9.2 ±â€¯7.4 ng/mL), estrone sulfate (E1S: 3.0 ±â€¯3.0 ng/mL), estriol 3-sulfate (E3S: 8.1 ±â€¯4.0 ng/mL) and estriol (E3: 1.2 ±â€¯0.4 ng/mL). Only testosterone (T) showed a significant sex difference (p < 0.0001). Correlations between AF steroids mirrored the steroid metabolism of the feto-placental unit, and not only confirmed the classical steroid pathway, but also pointed to a sulfated steroid pathway.


Asunto(s)
Líquido Amniótico/química , Segundo Trimestre del Embarazo/fisiología , Esteroides/análisis , 17-alfa-Hidroxipregnenolona/análisis , Androsterona/análisis , Cromatografía Liquida , Deshidroepiandrosterona/análisis , Epitestosterona/análisis , Estriol/análogos & derivados , Estriol/análisis , Estrona/análogos & derivados , Estrona/análisis , Femenino , Edad Gestacional , Humanos , Masculino , Embarazo , Pregnenolona/análisis , Espectrometría de Masas en Tándem
11.
Food Res Int ; 108: 387-395, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29735071

RESUMEN

Smoke has often been recommended as a masking agent for boar taint. However, guidelines on how much smoke is necessary have not been established. We compared different smoking parameters in bacon (smoking times) and sausages (smoking times and use of liquid smoke). In streaky bacon from entire male pigs with skatole concentrations of up to 0.6 µg/g and androstenone concentrations of up to 5.8 µg/g in the neck fat, three smoking times were compared: 10, 30 and 60 min. Boar taint was partially, but not fully, masked. The longer the smoking time, the better the masking effect. In sausages from entire male pigs with an average skatole concentration of up to 0.6 µg/g and androstenone concentration of up to 3.6 µg/g (the meat part) or 2.4 µg/g (the fat part) in the neck fat, smoking for 40 and 80 min fully masked the boar taint, whereas only a minor effect was seen after 10 and 20 min smoking. Liquid smoke (0.1%) did not mask boar taint when added to sausages from entire male pigs with an average skatole concentration of 0.36 µg/g (meat) or 0.38 µg/g (fat) and androstenone concentration of 2.3 µg/g (meat) and 2.9 µg/g (fat). To effectively mask boar taint, an intense smoked flavour is therefore necessary, and the longer the smoking time, the better. In contrast, the use of liquid smoke mixed into the product was not effective in the concentrations used in the current study.


Asunto(s)
Aromatizantes/química , Manipulación de Alimentos/métodos , Productos de la Carne/análisis , Carne Roja/análisis , Olfato , Humo , Gusto , Androsterona/análisis , Animales , Culinaria , Femenino , Calor , Humanos , Juicio , Masculino , Odorantes/análisis , Percepción Olfatoria , Escatol/análisis , Sus scrofa , Percepción del Gusto , Factores de Tiempo
12.
J Sci Food Agric ; 98(6): 2251-2257, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28981163

RESUMEN

BACKGROUND: Consumers highly sensitive to androstenone María (AND) will probably reject meat from entire male pigs, which tends to have high levels of this hormone. To avoid this, the effect of different masking strategies (sprinkling with mixed spices or fennel, marinating and breading with garlic-parsley or curry) on the sensory parameters of pork loin chops obtained from entire animals with high levels of AND (1.0-2.9 mg kg-1 AND in fat) and castrated animals (<0.4 mg kg-1 AND in fat), both with low levels of skatole (<0.1 mg kg-1 skatole in fat) was investigated. RESULTS: The garlic-parsley breadcrumbs led to the highest reduction in the perception of AND compared with the other masking strategies used, and preserved the juiciness of the product. There was a negative correlation between AND and fat content. CONCLUSION: AND odor and flavor can be reduced in meat from entire male pigs by using suitable strategies, the best strategy being the garlic-parsley breadcrumbs. © 2017 Society of Chemical Industry.


Asunto(s)
Androsterona/análisis , Culinaria/métodos , Carne/análisis , Percepción Olfatoria , Adulto , Animales , Comportamiento del Consumidor , Femenino , Aditivos Alimentarios/análisis , Ajo/química , Humanos , Masculino , Persona de Mediana Edad , Odorantes/análisis , Petroselinum/química , Escatol/análisis , Especias/análisis , Sus scrofa
13.
Meat Sci ; 136: 104-115, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29121524

RESUMEN

This study investigated the effects of ageing period (2 or 7days), endpoint temperature (70 or 75°C), cut type (loin (M. longissimus thoracis et lumborum), silverside (M. biceps femoris), blade (M. triceps brachii) and chuck tender (M. supraspinatus)), cooking method (roast and stir fry (all cuts) and steak (loin only)) on eating quality attributes of pork from entire and immunocastrated male pigs. Higher intramuscular fat levels were found in all cuts from immunocastrated males compared with entire males. Of the seven cut type×cooking method combinations evaluated, shoulder cuts had the lowest fail rate (P<0.001) and loin steak and silverside cuts scored lowest (P<0.001) for tenderness, juiciness, overall liking, quality grade and re-purchase intention. Although no differences in sensory scores due to gender were observed, boar taint was identified in 10% of entire males. Minimising adverse risks in eating quality due to boar taint in males remains a key industry issue to ensure consistent delivery of high quality pork.


Asunto(s)
Culinaria/métodos , Carne Roja/análisis , Adolescente , Adulto , Anciano , Androsterona/análisis , Animales , Distribución de la Grasa Corporal/veterinaria , Comportamiento del Consumidor , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/química , Orquiectomía/métodos , Orquiectomía/veterinaria , Escatol/análisis , Sus scrofa , Gusto
14.
Sci Rep ; 7(1): 12205, 2017 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-28939879

RESUMEN

Boar taint (BT) is an offensive odour or taste observed in pork from a proportion of non-castrated male pigs. Surgical castration is effective in avoiding BT, but animal welfare issues have created an incentive for alternatives such as genomic selection. In order to find candidate biomarkers, gene expression profiles were analysed from tissues of non-castrated pigs grouped by their genetic merit of BT. Differential expression analysis revealed substantial changes with log-transformed fold changes of liver and testis from -3.39 to 2.96 and -7.51 to 3.53, respectively. Co-expression network analysis revealed one module with a correlation of -0.27 in liver and three modules with correlations of 0.31, -0.44 and -0.49 in testis. Differential expression and co-expression analysis revealed candidate biomarkers with varying biological functions: phase I (COQ3, COX6C, CYP2J2, CYP2B6, ACOX2) and phase II metabolism (GSTO1, GSR, FMO3) of skatole and androstenone in liver to steroidgenesis (HSD17B7, HSD17B8, CYP27A1), regulation of steroidgenesis (STARD10, CYB5R3) and GnRH signalling (MAPK3, MAP2K2, MAP3K2) in testis. Overrepresented pathways included "Ribosome", "Protein export" and "Oxidative phosphorylation" in liver and "Steroid hormone biosynthesis" and "Gap junction" in testis. Future work should evaluate the biomarkers in large populations to ensure their usefulness in genomic selection programs.


Asunto(s)
Crianza de Animales Domésticos/métodos , Redes Reguladoras de Genes/genética , Carne/análisis , Redes y Vías Metabólicas/genética , Selección Artificial/genética , Androsterona/análisis , Androsterona/metabolismo , Animales , Biomarcadores/análisis , Estudios de Factibilidad , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Hígado/química , Masculino , Odorantes/análisis , Sitios de Carácter Cuantitativo/genética , Selección Genética , Escatol/análisis , Escatol/metabolismo , Sus scrofa/genética , Sus scrofa/metabolismo , Testículo/química , Testículo/metabolismo
15.
Talanta ; 169: 30-36, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28411818

RESUMEN

Boar taint is a contemporary off-odor present in meat of uncastrated male pigs. As European Member States intend to abandon surgical castration of pigs by 2018, this off-odor has gained a lot of research interest. In this study, rapid evaporative ionization mass spectrometry (REIMS) was explored for the rapid detection of boar taint in neck fat. Untargeted screening of samples (n=150) enabled discrimination between sow, tainted and untainted boars. The obtained OPLS-DA models showed excellent classification accuracy, i.e. 99% and 100% for sow and boar samples or solely boar samples, respectively. Furthermore, the obtained models demonstrated excellent validation characteristics (R2(Y)=0.872-0.969; Q2(Y)=0.756-0.917), which were confirmed by CV-ANOVA (p<0.001) and permutation testing. In conclusion, in this work for the first time highly accurate and high-throughput (<10s) classification of tainted and untainted boar samples was achieved, rendering REIMS a promising technique for predictive modelling in food safety and quality applications.


Asunto(s)
Tejido Adiposo/química , Androsterona/análisis , Análisis de los Alimentos/instrumentación , Ensayos Analíticos de Alto Rendimiento/instrumentación , Espectrometría de Masas/instrumentación , Carne/análisis , Tejido Adiposo/metabolismo , Animales , Análisis de los Alimentos/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Masculino , Espectrometría de Masas/métodos , Porcinos
16.
PLoS One ; 12(4): e0174697, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28380041

RESUMEN

While recent studies suggest an influence of noise on olfactory performance, it is unclear as to what extent the influence varies between subjects who are accustomed to noise and those who are not. Two groups of panelists were selected: a University panel usually working under silent conditions and an abattoir panel usually working on the slaughter line with abattoir noise. Odor discrimination, odor identification, and odor detection thresholds were studied. Furthermore, a sensory quality control task using 40 boar samples was performed. All tests were accomplished both with and without extraneous noise recorded at an abattoir (70 dB) using headphones. Contrary to the researchers' expectations, abattoir noise hardly affected the olfactory tests nor was the quality control task impaired. Abattoir noise did not influence the perceived intensity of boar taint and the classification results of the testers, regardless of whether they were accustomed to such noise or not. The results indicate that sensory quality control can be conducted in a manufacturing environment with constant noise without diminishing the assessors' performance.


Asunto(s)
Ruido/efectos adversos , Olfato/fisiología , Mataderos , Estimulación Acústica , Tejido Adiposo/química , Adulto , Androsterona/análisis , Animales , Humanos , Masculino , Carne/normas , Persona de Mediana Edad , Odorantes , Proyectos Piloto , Umbral Sensorial , Escatol/análisis , Porcinos
17.
Chem Biol Interact ; 276: 133-140, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28137513

RESUMEN

3α-Hydroxysteroid dehydrogenase/carbonyl reductase (3α-HSD/CR) catalyzes the oxidation of androsterone with NAD+ to form androstanedione and NADH with the rate limiting step being the release of NADH. In this study, we elucidate the role of remote substrate binding interactions contributing to the rate enhancement by 3α-HSD/CR through steady-state kinetic studies with the truncated substrate analogs. No enzyme activity was detected for methanol, ethanol, and 2-propanol, which lack the steroid scaffold of androsterone, implying that the steroid scaffold plays an important role in enzyme catalytic specificity. As compared to cyclohexanol, the activity for 2-decalol, androstenol, and androsterone increases by 0.9-, 90-, and 200-fold in kcat, and 37-, 1.9 × 106-, and 1.8 × 106-fold in kcat/KB, respectively. The rate limiting step is hydride transfer for 3α-HSD/CR catalyzing the reaction of cyclohexanol with NAD+ based on the observed rapid equilibrium ordered mechanism and equal deuterium isotope effects of 3.9 on V and V/K for cyclohexanol. The kcat/KB value results in ΔG‡ of 14.7, 12.6, 6.2, and 6.2 kcal/mol for the 3α-HSD/CR catalyzed reaction of cyclohexanol, 2-decalol, androstenol, and androsterone, respectively. Thus, the uniform binding energy from the B-ring of steroids with the active site of 3α-HSD/CR equally contributes 2.1 kcal/mol to stabilize both the transition state and ground state of the ternary complex, leading to the similarity in kcat for 2-decalol and cyclohexanol. Differential binding interactions of the remote BCD-ring and CD-ring of androsterone with the active site of 3α-HSD/CR contribute 8.5 and 6.4 kcal/mol to the stabilization of the transition state, respectively. The removal of the carbonyl group at C17 of androsterone has small effects on catalysis. Both uniform and differential binding energies from the remote sites of androsterone compared to cyclohexanol contribute to the 3α-HSD/CR catalysis, resulting in the increases in kcat and kcat/KB.


Asunto(s)
Hidroxiesteroide Deshidrogenasas/metabolismo , Androsterona/análisis , Androsterona/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Biocatálisis , Dominio Catalítico , Cromatografía Líquida de Alta Presión , Comamonas testosteroni/enzimología , Deuterio/química , Hidroxiesteroide Deshidrogenasas/química , Cinética , NAD/química , NAD/metabolismo , Oxidación-Reducción , Especificidad por Sustrato , Espectrometría de Masas en Tándem , Termodinámica
18.
Zoo Biol ; 36(2): 127-131, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28114737

RESUMEN

The aim of this study was to determine whether concentrations of reproductive steroid hormone metabolites significantly differed between harem stallions and bachelor stallions in the free ranging group of Przewalski's horses (Equus ferus przewalskii) at the Hortobágy National Park in Hungary. Throughout the study, fecal samples were collected from 21 harem stallions and 15 bachelor stallions and analyzed for immunoreactive estrogen and androgen metabolites. Harem stallions demonstrated significantly higher concentrations of estrogen (P < 0.001) and epi-androsterone (P < 0.001), but not testosterone (P = 0.426). These findings confirm that sociosexual status has a significant effect on androgen concentrations in individual Przewalski stallions. Zoo Biol. 36:127-131, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Androsterona/análisis , Estrógenos/análisis , Heces/química , Caballos/fisiología , Animales , Animales de Zoológico , Masculino
19.
J Steroid Biochem Mol Biol ; 165(Pt B): 212-218, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27328448

RESUMEN

Testosterone (T) has traditionally been the most commonly reported doping agent by doping control laboratories. The screening of T misuse is performed by the quantification of six endogenous androgenic steroids and the ratio T/E included in the Athlete Biological Passport (ABP). The inclusion of additional metabolites can improve the screening capabilities of ABP. In this study, the potential of 3α-glucuronide-6ß-hydroxyandrosterone (6OH-Andros3G) and 3α-glucuronide-6ß-hydroxyetiocholanolone (6OH-Etio3G) as markers of T oral administration was evaluated. These glucuronides have been shown to be resistant to enzymatic hydrolysis and their quantification by means of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was reported as the only way to obtain feasible results. Urine samples were collected from five volunteers before and after the oral administration of 40mg of T undecanoate and were analyzed by a LC-MS/MS method recently developed. Concentration of 6OH-Andros3G and 6OH-Etio3G compounds and those of the glucuronides of T (TG), epitestosterone (EG), androsterone and etiocholanolone were established and different concentration ratios were calculated. The detection windows (DWs) for the T administration obtained by each selected ratio were compared to the one of TG/EG. The results showed that four out of the nine tested markers presented DWs much larger for all volunteers than those obtained by the World Anti-Doping Agency established T/E marker or other alternative markers. The 6OH-Andros3G/EG, 6OH-Etio3G/EG, 6OH-Andros3G/TG and 6OH-Etio3G/TG markers were able to identify the T abuse up to 96h after the administration, extending our detection capability for the misuse up to 84h more than the classic marker. The importance of these markers was also highlighted by their prolonged capacity to detect the T misuse in the case of one volunteer whose TG/EG barely exceeded his individual threshold. As a consequence, the four markers presented in this study seem to have an exceptional potential as biomarkers of T oral administration.


Asunto(s)
Glucurónidos/análisis , Detección de Abuso de Sustancias/métodos , Testosterona/análogos & derivados , Administración Oral , Androsterona/análisis , Biomarcadores/análisis , Cromatografía Líquida de Alta Presión , Doping en los Deportes/prevención & control , Epitestosterona/análisis , Etiocolanolona/análisis , Cromatografía de Gases y Espectrometría de Masas , Voluntarios Sanos , Humanos , Hidrólisis , Masculino , Reproducibilidad de los Resultados , Esteroides/análisis , Espectrometría de Masas en Tándem , Testosterona/administración & dosificación , Testosterona/análisis
20.
Meat Sci ; 123: 1-7, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27579788

RESUMEN

Yeast inoculation of dry fermented sausages manufactured with entire male fat was evaluated as a strategy to improve sausage quality. Four different formulations with entire male/gilt back fat and inoculated/non-inoculated with Debaryomyces hansenii were manufactured. The use of entire male back fat produced the highest weight losses, hardness and chewiness in dry sausages. Consumers clearly distinguished samples according to drying time and D. hansenii inoculation while the use of entire/gilt back fat was not highly perceived. The presence of androstenone and skatole was close to their sensory thresholds. Androstenone was not degraded during the process but skatole was affected by yeast inoculation. D. hansenii growth on the surface regulated water release during ripening, reduced hardness and chewiness in entire male sausages and resulted with similar texture to gilt sausages. Yeast inoculation inhibited lipid oxidation providing fruity odours and less oxidized fatty sausages in the sensory analysis. The effectiveness of yeast to mask boar taint was demonstrated by sensory analysis.


Asunto(s)
Tejido Adiposo/química , Productos de la Carne/análisis , Saccharomycetales , Levaduras , Adulto , Androsterona/análisis , Color , Comportamiento del Consumidor , Desecación , Grasas de la Dieta/análisis , Femenino , Microbiología de Alimentos , Calidad de los Alimentos , Humanos , Lactobacillus , Masculino , Persona de Mediana Edad , Escatol/química , Olfato , Cloruro de Sodio Dietético/análisis , Staphylococcus , Gusto , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis
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