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Um Alternativen zum Mais (Zea mays) als Co-Substrat für die Biogas-Produktion zu finden, wurden Nutzpflanzen aus der Familie der Brassicaceae auf ihr Biogaspotential untersucht. Von besonderem Interesse waren dabei die Glucosinolate und ihre antimikrobiell wirkenden Spaltprodukte (Isothiocyanate), die charakteristisch für diese Pflanzenfamilie sind. Dazu wurden Feldversuche und Biogas-Versuche mit acht Zwischenfrucht- und fünf Gemüsearten aus der Familie der Brassicaceae durchgeführt. Außerdem wurden Vorkommen und Zusammensetzung der Isothiocyanate (ITC) mittels GC/MS analysiert. Die Ergebnisse der Biogasversuche wurden mit dem Biogasbildungspotential (berechnet) der jeweiligen Art bzw. Sorte verglichen. In den vier Feldversuchen mit kruziferen Zwischenfrüchten konnten für die Prüfmerkmale Frischmasse-Ertrag, Trockenmassegehalt und Trockenmasseertrag signifikante Unterschiede zwischen den Mittelwerten der Stickstoff-Düngungsstufen und den Mittelwerten der acht Arten (bzw. sechzehn Sorten) festgestellt werden. Die ITC-Gehalte der Zwischenfrucht-Arten wurden durch die Art und Dauer der Probenlagerung, aber auch durch die Stickstoffverfügbarkeit und Frosteinwirkung während der Vegetationszeit beeinflusst. Aufgrund natürlicher Abbauprozesse verringerten sich die ITC-Gehalte in silierten Proben auf annähernd 0,0 µmol 100 g-1 Trockenmasse (TM). In einem von vier Batchversuchen zeigte Mais eine höhere Biogasbildung als die kruziferen Substrate, während er in den anderen Versuchen eine vergleichsweise geringere Biogasbildung aufwies. Die Biogasausbeute der kruziferen Zwischen-früchte war somit vergleichbar mit jener der Maisvariante. Die meisten Arten erreichten das für sie berechnete Methanbildungspotential innerhalb der Versuche. Es wurden keine inhibierenden Effekte durch ITC-Verbindungen oder hohe Schwefelwasserstoffkonzentrationen auf die Gasbildung im Fermenter nachge-wiesen. Das Entwicklungsstadium und somit der Rohfasergehalt der Arten spielen hingegen eine entscheidende Rolle. Infolge des geringen TM-Gehaltes ist es empfehlenswert, diese Arten gemischt mit TM-reichem Pflanzenmaterial (z. B. Stroh) zu verwenden. To find another alternative to maize (Zea mays) as biogas co-substrate, selected crops from the family Brassicaceae were investigated on their biogas potential. Of mainly interest were the secondary ingredients (glucosinolates) and their antimicrobial-acting degradation products (isothiocyanates), which are characteristic for this plant family. Therefore field trials and biogas experiments were carried out with eight catch crops and five vegetable species of the family Brassicaceae. In addition, the isothiocyanates were analyzed by gas chromatography using GC/MS. The results of the biogas tests were compared with the calculated biogas potential of the species or varieties. In the field trial with catch crops significant differences could be ascertained for the test factor fresh mass, dry mass content and dry mass yield in all N-fertilization levels between the middle values of sixteen varieties (or eight species). The isothiocyanate (ITC) levels of cover crop species were affected by the type and duration of sample storage, but also by the availability of nitrogen and frost during the growing season. Due to natural degradation processes, the ITC-levels decreased in ensiled samples to approximately 0.0 µmol 100 g-1 dry matter (DM). In one of four batch experiments maize was superior to the cruciferous substrates in biogas formation while it produced lower biogas amounts in the other experiments. The biogas yield of cruciferous catch crops was thus comparable to the biogas yield of the maize variant. Most species reached the calculated methanogenic potential for them within the experiments. No inhibitory effects were detected by isothiocyanates or high hydrogen sulfide concentrations in the gas production. The stage of development, and thus the fiber content of the species on the other hand play a crucial role. Due to the low DM-content, it is advisable to use substrates mixed with ones types with higher dry matter content.

Um Alternativen zum Mais (Zea mays) als Co-Substrat für die Biogas-Produktion zu finden, wurden Nutzpflanzen aus der Familie der Brassicaceae auf ihr Biogaspotential untersucht. Von besonderem Interesse waren dabei die Glucosinolate und ihre antimikrobiell wirkenden Spaltprodukte (Isothiocyanate), die charakteristisch für diese Pflanzenfamilie sind. Dazu wurden Feldversuche und Biogas-Versuche mit acht Zwischenfrucht- und fünf Gemüsearten aus der Familie der Brassicaceae durchgeführt. Außerdem wurden Vorkommen und Zusammensetzung der Isothiocyanate (ITC) mittels GC/MS analysiert. Die Ergebnisse der Biogasversuche wurden mit dem Biogasbildungspotential (berechnet) der jeweiligen Art bzw. Sorte verglichen.In den vier Feldversuchen mit kruziferen Zwischenfrüchten konnten für die Prüfmerkmale Frischmasse-Ertrag, Trockenmassegehalt und Trockenmasseertrag signifikante Unterschiede zwischen den Mittelwerten der Stickstoff-Düngungsstufen und den Mittelwerten der acht Arten (bzw. sechzehn Sorten) festgestellt werden.Die ITC-Gehalte der Zwischenfrucht-Arten wurden durch die Art und Dauer der Probenlagerung, aber auch durch die Stickstoffverfügbarkeit und Frosteinwirkung während der Vegetationszeit beeinflusst. Aufgrund natürlicher Abbauprozesse verringerten sich die ITC-Gehalte in silierten Proben auf annähernd 0,0 µmol 100 g-1 Trockenmasse (TM). In einem von vier Batchversuchen zeigte Mais eine höhere Biogasbildung als die kruziferen Substrate, während er in den anderen Versuchen eine vergleichsweise geringere Biogasbildung aufwies. Die Biogasausbeute der kruziferen Zwischen-früchte war somit vergleichbar mit jener der Maisvariante. Die meisten Arten erreichten das für sie berechnete Methanbildungspotential innerhalb der Versuche. Es wurden keine inhibierenden Effekte durch ITC-Verbindungen oder hohe Schwefelwasserstoffkonzentrationen auf die Gasbildung im Fermenter nachge-wiesen. Das Entwicklungsstadium und somit der Rohfasergehalt der Arten spielen hingegen eine entscheidende Rolle. Infolge des geringen TM-Gehaltes ist es empfehlenswert, diese Arten gemischt mit TM-reichem Pflanzenmaterial (z. B. Stroh) zu verwenden., To find another alternative to maize (Zea mays) as biogas co-substrate, selected crops from the family Brassicaceae were investigated on their biogas potential. Of mainly interest were the secondary ingredients (glucosinolates) and their antimicrobial-acting degradation products (isothiocyanates), which are characteristic for this plant family. Therefore field trials and biogas experiments were carried out with eight catch crops and five vegetable species of the family Brassicaceae. In addition, the isothiocyanates were analyzed by gas chromatography using GC/MS. The results of the biogas tests were compared with the calculated biogas potential of the species or varieties. In the field trial with catch crops significant differences could be ascertained for the test factor fresh mass, dry mass content and dry mass yield in all N-fertilization levels between the middle values of sixteen varieties (or eight species). The isothiocyanate (ITC) levels of cover crop species were affected by the type and duration of sample storage, but also by the availability of nitrogen and frost during the growing season. Due to natural degradation processes, the ITC-levels decreased in ensiled samples to approximately 0.0 µmol 100 g-1 dry matter (DM). In one of four batch experiments maize was superior to the cruciferous substrates in biogas formation while it produced lower biogas amounts in the other experiments. The biogas yield of cruciferous catch crops was thus comparable to the biogas yield of the maize variant. Most species reached the calculated methanogenic potential for them within the experiments. No inhibitory effects were detected by isothiocyanates or high hydrogen sulfide concentrations in the gas production. The stage of development, and thus the fiber content of the species on the other hand play a crucial role. Due to the low DM-content, it is advisable to use substrates mixed with ones types with higher dry matter content.

Indole und Isothiocyanate gehen aus den Glucosinolaten durch enzymatische Aufspaltung hervor. In der Natur kommen sie vor allem in Vertretern der Brassicaceae-Familie vor. Schon seit mehreren Jahren haben ITCs und Indole immer wieder chemopräventives Potential in verschiedenen Studien unter Beweis gestellt.In der vorliegenden Arbeit wurden die zwei Indole Brassinin und Indol(3)carbinol sowie das ITC Erysolin hinsichtlich ihres gentoxischen, antigentoxischen sowie zytotoxischen Potentials in humanen Hepatomzellen (HepG2) mittels Cometassay, Mikronukleustest, WST-1- und Erythrosin- B-Assay untersucht.Dabei zeigte Erysolin in Cometassay und Mikrokerntest in einem Konzentrationsbereich von 1,25 -5 µM antigentoxisches Potential gegenüber B(a)P demonstriert durch eine signifikante Reduktion von Mikrokernfrequenz und DNA-Migration. Bei höheren Konzentrationen kam es in den Vitalitätsuntersuchungen bei kombinierter ITC/B(a)P-Exposition zu einer deutlichen Reduktion der Vitalität, so dass hier Aussagen zu zytotoxischen Effekten oder Apoptoseinduktion in weiteren Studien untersucht werden müssen.Indol(3)carbinol zeigte im HepG2-Modell lediglich in den Mikrokernuntersuchungen ein leicht antigentoxisches Potential. Auffällig war dagegen eine erhöhte DNA-Migration im Vergleich zur Positivkontrolle bei kombinierter I3C/B(a)P-exposition im Cometassay welche mit erhöhter Zytotoxizität in Erythrosin-B und WST-1 Assay korrelierte. Hier sind weitere Untersuchungen insbesondere zur Sicherheit von I3C in der chemopräventiven Pharmakotherapie notwendig, da letztendlich mutagene und tumorpromovierende Eigenschaften von Indol(3)carbinol bereits in anderen Zell- und Tiermodellen nachgewiesen wurden.In der SCGE mit Brassinin konnte keine Dosis-Wirkungsbeziehung nachgewiesen werden, so dass auf einen Mikronukleustest verzichtet wurde. Die Tatsache das Brassinin seine chemopräventive Wirkung unter anderem durch Inhibition des extrahepatischen Enzyms Indolamin2, 3-Dioxygenase entfaltet, ist hier nur eine mögliche Erklärung für den fehlenden Effekt im HepG2-modell des noch weitgehend unerforschten Indols. Es bedarf deshalb noch weiterer Untersuchungen über die genauen Wirkungsmechanismen von Brassinin und seiner möglichen Effekte., Indoles and isothiocyanates arise from the glucosinolates by enzymatic lysis. Their natural sources are members of the Brassica plant family. During the past years, ITCs and Indoles demonstrated their chemopreventive potency in many different studies.In the present study genotoxic, antigenotoxic or cytotoxic effects of two indoles, brassinin and indole(3)carbinol and the ITC erysolin in human hepatomacells (HepG2) were investigated in the cometassay, mikronucleusassay, WST-1- and erythrosine-B-assay.Erysolin demonstrated its antigenotoxic potency versus B(a)P, showing a significant reduction of the DNA-migration and also a reduction of the micronucleus frequency at a concentration from 1, 25 µM up to 5 µM when cells were treated with erysolin and B(a)P. A distinct loss of viability was observed in the investigations of cell viability with combined ITC/B(a)P-treatment at higher concentrations. In this context predictions about cytotoxic effects or the induction of apoptosis have to be observed in further studies.Only in the micronucleustest indole(3)carbinol demonstrated al light antigenotoxic potency in HepG2-modell. Strikingly we investigated here an increased DNA-migration compared with the positivecontrol in the cometassay which was associated with an increased cytotoxicity in the erythrosine-B- and WST-1-assay when cells where treated with I3C and B(a)P. Further investigations have to be made particularly about the safety of I3C in chemopreventive pharmacological therapy, because mutagenic and tumor promoting effects have already been proved in other cell- or animal models.In the SCGE, brassinin did not show any dose-dependent relationship, so we passed the micronucleus test. A mistake in the dilution series was excluded. The fact that brassinin unfolds its chemopreventive effects e.g. by inhibiting the extrahepatic enzyme IDO is only one possibility why no effect of the widely unexplored indole brassinin could be observed in the HepG2-modell. Therefore further studies should be conducted to examine the exact mechanisms of action and possible effects of brassinin more closely.

Glucosinolate (GSL) stellen eine wichtige Gruppe sekundärer Pflanzeninhaltsstoffe dar. Sie dienen als Präkursoren charakteristischer Aromaverbindungen, üben aber auch sowohl positive als auch negative physiologische Effekte im Menschen aus. Deshalb sind qualitative und quantitative Methoden zur Bestimmung der intakten GSL sowie der daraus gebildeten Abbauprodukte, den Isothiocyanaten (ITCs), erforderlich. Zur Bestimmung der nativen GSL wurden zwei Hochleistungsflüssigkeits-chromatographische (HPLC) Methoden unter Verwendung einer Varian Polaris® C18-Ether und einer Phenomenex Luna® HILIC Säule entwickelt. Durch Gradientenelution bzw. unter isokratischen Bedingungen und UV-Detektion konnten mit 12 bzw. 14 GSL getrennt und mittels kommerziell erhältlichen Standards quantifiziert werden. Die HILIC-Säule (hydrophilic interaction chromatography) wurde mit Elektrospray-ionisierungs-Massenspektrometrie (ESI-MS) gekoppelt und ermöglichte die Bestimmung der Anwesenheit und die Charakterisierung von GSL in pflanzlichen Materialien. Zur Analyse der flüchtigen ITCs wurde eine effektive Methode mittels Gaschromatographie - Massenspektrometrie (GC-MS) entwickelt. Unter Verwendung einer Varian FactorFourTM VF-35ms Kapillarsäule konnten 11 kommerziell erhältliche Standard-ITCs innerhalb von 18 Minuten getrennt werden. Mittels der HPLC und GC-MS Methoden wurden auch eine große Zahl nativer und prozessierter pflanzlicher Nahrungsmittel und einige Nahrungsergänzungsmittel untersucht. Art und Menge der GSL und ITCs in den pflanzlichen Materialen waren in guter Übereinstimmung mit den Literaturwerten. Die HPLC-ESI-MS Methode wurden ebenfalls zur Untersuchung von medizinischen Nahrungspflanzen eingesetzt wie z.B. Moringa drouhardii, von welcher vorher noch kein GSL-Profil erstellt worden war. Die entwickelten Methoden zur Quantifizierung intakter GSL und der daraus gebildeten ITCs eignen sich zur Analyse nativer und prozessierter pflanzlicher Materialien, zur Qualitäts- und Authentizitätskontrolle von Lebensmitteln und auch zur Prüfung gesundheitsbezogener Auslobungen bezüglich der Anwesenheit von GSL und ITCs in bestimmten Nahrungsergänzungsmitteln. Glucosinolates (GSLs) represent an important group of secondary plant metabolites. They are precursors of characteristic flavour compounds but are also known to exert both positive and negative physiological effects in human beings. Therefore, qualitative and quantitative methods for the determination of intact GSLs and their main breakdown products, the isothiocyanates (ITCs), are required. For the determination of native GSLs two high performance liquid chromatographic (HPLC) methods were developed using either a Varian Polaris® C18-Ether column or Phenomenex Luna® HILIC column. Using gradient elution or isocratic system and UV detection twelve or fourteen GSLs could be separated and quantified in plant materials by comparison with commercially available GSL standards. HILIC (hydrophilic interaction chromatography) was combined with electrospray- ionization mass-spectrometry (ESI-MS) in order to establish the presence and characterization of GSLs in plant materials. For the analysis of volatile ITCs an efficient gas-chromatographic mass-spectrometric (GC-MS) method was developed. Using a Varian FactorFourTM VF-35ms capillary column, 11 commercially available standard ITCs could be resolved in 18 minutes. The method was used for the determination of ITCs in plant materials. The HPLC and GC-MS methods were applied to a large number of native and processes foodstuffs and some food additives. Quantities of GSLs and ITCS in plant materials were in good accordance with data reported in the literature. HPLC-ESI-MS was also used for the investigation of medical food plants such as Moringa drouhardii that was previously not analysed for its GSL profile. The HPLC and GC methods developed for the quantification of native GSLs and ITCs released thereof are suitable for analyzing native and processed plant materials, food quality and authenticity control, and for proving health claims related to the presence of GSLs and ITCS in certain food supplements.

Glucosinolate (GSL) stellen eine wichtige Gruppe sekundärer Pflanzeninhaltsstoffe dar. Sie dienen als Präkursoren charakteristischer Aromaverbindungen, üben aber auch sowohl positive als auch negative physiologische Effekte im Menschen aus. Deshalb sind qualitative und quantitative Methoden zur Bestimmung der intakten GSL sowie der daraus gebildeten Abbauprodukte, den Isothiocyanaten (ITCs), erforderlich.Zur Bestimmung der nativen GSL wurden zwei Hochleistungsflüssigkeits-chromatographische (HPLC) Methoden unter Verwendung einer Varian Polaris® C18-Ether und einer Phenomenex Luna® HILIC Säule entwickelt. Durch Gradientenelution bzw. unter isokratischen Bedingungen und UV-Detektion konnten mit 12 bzw. 14 GSL getrennt und mittels kommerziell erhältlichen Standards quantifiziert werden. Die HILIC-Säule (hydrophilic interaction chromatography) wurde mit Elektrospray-ionisierungs-Massenspektrometrie (ESI-MS) gekoppelt und ermöglichte die Bestimmung der Anwesenheit und die Charakterisierung von GSL in pflanzlichen Materialien.Zur Analyse der flüchtigen ITCs wurde eine effektive Methode mittels Gaschromatographie - Massenspektrometrie (GC-MS) entwickelt. Unter Verwendung einer Varian FactorFourTM VF-35ms Kapillarsäule konnten 11 kommerziell erhältliche Standard-ITCs innerhalb von 18 Minuten getrennt werden.Mittels der HPLC und GC-MS Methoden wurden auch eine große Zahl nativer und prozessierter pflanzlicher Nahrungsmittel und einige Nahrungsergänzungsmittel untersucht. Art und Menge der GSL und ITCs in den pflanzlichen Materialen waren in guter Übereinstimmung mit den Literaturwerten.Die HPLC-ESI-MS Methode wurden ebenfalls zur Untersuchung von medizinischen Nahrungspflanzen eingesetzt wie z.B. Moringa drouhardii, von welcher vorher noch kein GSL-Profil erstellt worden war.Die entwickelten Methoden zur Quantifizierung intakter GSL und der daraus gebildeten ITCs eignen sich zur Analyse nativer und prozessierter pflanzlicher Materialien, zur Qualitäts- und Authentizitätskontrolle von Lebensmitteln und auch zur Prüfung gesundheitsbezogener Auslobungen bezüglich der Anwesenheit von GSL und ITCs in bestimmten Nahrungsergänzungsmitteln., Glucosinolates (GSLs) represent an important group of secondary plant metabolites. They are precursors of characteristic flavour compounds but are also known to exert both positive and negative physiological effects in human beings. Therefore, qualitative and quantitative methods for the determination of intact GSLs and their main breakdown products, the isothiocyanates (ITCs), are required.For the determination of native GSLs two high performance liquid chromatographic (HPLC) methods were developed using either a Varian Polaris® C18-Ether column or Phenomenex Luna® HILIC column. Using gradient elution or isocratic system and UV detection twelve or fourteen GSLs could be separated and quantified in plant materials by comparison with commercially available GSL standards. HILIC (hydrophilic interaction chromatography) was combined with electrospray- ionization mass-spectrometry (ESI-MS) in order to establish the presence and characterization of GSLs in plant materials. For the analysis of volatile ITCs an efficient gas-chromatographic mass-spectrometric (GC-MS) method was developed. Using a Varian FactorFourTM VF-35ms capillary column, 11 commercially available standard ITCs could be resolved in 18 minutes. The method was used for the determination of ITCs in plant materials.The HPLC and GC-MS methods were applied to a large number of native and processes foodstuffs and some food additives. Quantities of GSLs and ITCS in plant materials were in good accordance with data reported in the literature. HPLC-ESI-MS was also used for the investigation of medical food plants such as Moringa drouhardii that was previously not analysed for its GSL profile.The HPLC and GC methods developed for the quantification of native GSLs and ITCs released thereof are suitable for analyzing native and processed plant materials, food quality and authenticity control, and for proving health claims related to the presence of GSLs and ITCS in certain food supplements.

Feed containing rapeseed meal (RSM) with high glucosinolate content (10 mmol/kg feed) induced a strong increase of thyroid weight in pigs and poultry. Supplementary iodine reduced the antithyroid effect, but, it could not cancel it. Only at a low glucosinolate content (0.7 mmol/kg feed) a normal weight of thyroid was established. As the iodine supplementation increased the serum T4 value increased. The thiocyanate serum level increased irrespective of glucosinolate content of the feed. The urine level was significantly decreased due to lower dietary glucosinolate level. Obviously, the goitrogenic effect of the RSM does not correlate with the increased thiocyanate serum level.

Glucosinolates are present in kale but also in rapeseed meal. Rapeseed meal diets with 0.2 to 8 g (0.5-19 mmol) glucosinolates/kg were tested with a total of 197 growing pigs. The iodine supply was different. In case of lacking iodine pigs consumed less of feed with rapeseed meal. The growth was strongly lowered. Clinical hypothyroidism had occurred. In the serum T4 was not detectable. The strongly enlarged thyroid contained only little iodine. The Zn status was impaired. The serum vitamin A concentration was increased and Cu has been accumulated in the liver. Giving iodine the glucosinolates were without any effect or the effects were weakened. In case of2 g glucosinolates/kg diet the feed intake was not impaired. 1 g glucosinolates/kg diet had not affected thyroid weight (reference range: 80-120 mg/kg body weight). However iodine dosage was above requirement. In people an estimated daily intake of 0.1 g glucosinolates may be a health risk only under iodine deficiency conditions.

Beginning with the simultaneous occurrence of the first extensive sowing of 00-rape and local increased losses among hares and roe deer in Western Germany and Austria at the end of 1986, the clinical and morphological symptoms of rape poisoning are discussed. They consist of damage to endo- and epithelium, cell membranes, blood, liver and in the so called "rape-blindness". Subsequently, the most important toxic agents of rape including their metabolites are presented. They consist in alkenyl- and indolyl-glucosinolates, leading to isothiocyanates (mustard oils), thiocyanates or thiocyanate ions resp., nitriles and antithyroid agents (e.g. goitrin) as well as S-methylcysteine sulphoxide and its metabolites, particularly dimethyl disulphide. Finally, the activity spectrum of the toxic agents or the metabolites and the clinical picture of the affected wildlife in 1986 are compared with the result that the losses of that period are most likely to be traced back to rape poisoning and that the rape-blindness mentioned is to be interpreted as a thiocyanate-psychosis.

In two digestibility and N-balance experiments the following solvent extracted meals were examined in a grain (barley and wheat in equal parts) or in a starch diet with four female pigs/group fitted with urethra catheters during the 5 days sampling period: 48% soyabean meal (SBM) (1), 24% conventional rapeseed meal (RSM) (2), 24 (3) or 48% (4) RSM from a newly bred low glucosinolate variety, groups 1 to 4 with grain, 48% low glucosinolate RSM (5) or 48% SBM (6) both with starch. In numeric order of the groups 88, 85, 86, 84, 79 and 89% N were digested. Pigs responded to the additional faecal N excretion from RSM diets by a lower urinary N excretion and thus they reached the N-balance of the animals fed on SBM. In numeric order of the groups 86, 79, 80, 73, 73 and 92% of the organic matter of the solvent extracted meals were digested. In comparison with SBM even 48% RSM in the feed significantly lowered the digestibility of organic matter. Using detergents the additional faecal organic matter excretion of RSM versus SBM could quantified as two third lignin. In the case of 24% RSM in the diet--i.e. 15% of the carbohydrates given--the carbohydrate digestibility is estimated with a high error, that an energetic feed value should not calculated. Investigating 48% SBM or RSM respectively in a grain diet the net energy content was 9.8 MJ (666 Energetic Feed Units, EFU pig) or 8.3 MJ (569 EFU pig)/kg dry matter (DM). Based on the starch diet, however, little relevant for estimation of normal pig diets, there were evaluated 10.6 MJ (720 EFU pig) for SBM and 8.3 MJ (567 EFU pig) net energy/kg DM for RSM.

In the experiment, 2 x 12 growing pigs received 19 or 6.7 mmol glucosinolates + aglucones/kg feed via conventional rapeseed meal (RSM) or RSM of a newly bred variety. These pigs and 24 littermates pair fed with a soya bean meal (SBM) diet were subdivided in groups of 4 animals each. Their diet contained either no supplementary iodine or an iodine supplementation of up to 1 mg/kg feed. In the RSM and SBM groups the lack of additional iodine lowered the serum T4 and T3 content below the detection limit and caused goitre with about 1 mg iodine in the total thyroid. The SBM diet with 0.0625 mg supplementary iodine/kg increased the serum T4 level and reversed the thyroid enlargement but not that of epithelial cells. The hypothyroidism (goitre and serum T4 level approximately 10 nmol/l) still existed in the case of this iodine dosage together with the RSM of the newly bred variety. A serum T4 level comparable to that of the animals fed SBM was only reached by supplementing the low glucosinolate diet with 0.25 mg iodine/kg feed. The iodine content of the thyroid, however, was reduced by 50 per cent. Though thyroid and epithelial cells were enlarged, this enlargement was not so obvious as in animals exposed to higher glucosinolate level. In spite of 1 mg supplementary iodine/kg feed, the feeding of the conventional RSM resulted in a lower serum T4 level a reduced thyroid iodine content and the enlargement of thyroid and that of epithelial cells. Compared to the high glucosinolate RSM, a significantly lower antithyroid effect of the low glucosinolate RSM was found in pigs with iodine supply. The degree of thyroid enlargement and the serum T4 level were the criteria.

In a feeding experiment with 48 growing pigs 16% high glucosinolate rapeseed meal (HGRSM) (136 mumol glucosinolates + aglucones/kg dry matter, DM) or low glucosinolate (LG) RSM (48 mumol glucosinolates + aglucones/kg DM) in the feed were compared with 14% soya-bean meal (SBM) in each case. It were established 24 pairs of animals, which received the same quantity of the isonitrogenous but not isocaloric diets with SBM and the both RSM (pair fed). Four of the 2.12 animal pairs were not given supplementary I, four received 0.25 mg supplementary I/kg feed. Further four animals which were fed on LGRSM or HGRSM were provided with 0.0625 or 1 mg supplementary I/kg feed. In case of high glucosinolate intake (HGRSM) the lacking I supplementation decreased feed intake and growth and led to remarkable I deficiency symptoms from the fifth week onwards. The 2/3 lower glucosinolate dosage of the LGRSM diet also decreased performance and provoked I deficiency, however significantly later. The investigated I dosages (greater than 0.0625 mg/kg feed) did not effect the performance. In the experiment the eight animals which received LGRSM with supplementary I consumed 13% more feed than animals fed on HGRSM (P less than 0.05). The additional weight gain was 20% (P less than 0.05). Comparing the live weight gain of the SBM and RSM fed animals (pair fed) there was a significant increase of 9% versus the HGRSM groups and 5% versus the LGRSM groups.

During the degradation of thioglucosides in defatted rape seed meal (RES) microorganisms were found, whose ability to degrade glucosinolates (GSL) and vinyl thio-oxazolidone (VTO) was not known so far. The isolated microorganisms are two strains of bacteria of the species Bacillus cereus and the yeast Trichosporon cutaneum. The degradation of GSL and VTO in the cultural broths by the Bacillus cereus strains was the more complete the more other Gram-negative bacteria from RES were additionally present. Drinking tests with Wistar rats showed that here is a relation between the watersoluble and mainly bitter toxin substances of rape and their influence on the increase of the animals body weight.

Industrial and laboratory-scale studies showed that the combined silage fermentation of rape-seed flakes with half sugar mangels leds to a very beneficial reduction in the content of glucosinolate derivatives, especially during the first week of fermentation and storage processes on the qualitative and quantitative fatty-acid parameters were but significant.

Microbiological biotransformation as a part of metabolism of foreign compounds in general, has great toxicological consequences. An overview on the most important types of reactions is given. In detail, comparative investigations of the metabolism of gamma-HCH, azobenzene and progoitrin in germfree and conventionalized rats are described and results from the literature are presented.