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In den Pflanzenzellwänden befindliche Polysaccharide stehen dem Prozess nur bedingt als Energiequelle zur Verfügung, da diese in einem Komplex mit Lignin verknüpft sind. Um diese Substanzen für den Biogasprozess verfügbar zu machen und demnach den Substratumsatz bzw. die Prozesseffizienz zu erhöhen, sind geeignete Stoffe oder Techniken einzusetzen bzw. zu entwickeln. In dieser Arbeit wurde zielführend der Einsatz von unterschiedlichen Enzympräparaten in drei verschiedenen Prozessstufen bei ausgewählten Energiepflanzen mit variierender Häcksellänge untersucht. Anhand von Enzymaktivitätsbestimmungen konnten Enzympräparate für die einzelnen Stufen selektiert werden. Die ausgewählten Enzyme wurden einzeln oder in Mischung während der Silierung, direkt vor dem Biogasprozess sowie während des Biogasprozesses zum Substrat dotiert und dieses nach der jeweiligen Vorbehandlung in Batch-Gärtests vergoren. Neben der Biogas- und Methanausbeute wurde zur Bewertung der Enzymleistung der Abbau an Lignocellulose sowie die Freisetzung an niedermolekularen Kohlenhydraten ermittelt. Zusätzlich wurde das Quellen der Lignocellulose mit Hilfe eines Wasserzusatzes in Form einer Vorhydrolyse als Vorbehandlungsmethode mit allgemein positivem Ergebnis geprüft. Das Ziel der verbesserten Substratumsetzung bei Mais und Roggen und folglich einer Erhöhung der Biogasproduktion wurde durch den Zusatz ausgewählter Enzympräparate erreicht. Es konnten Grundlagen bezüglich der Wirkung von Enzymen in Biogasprozessen geschaffen werden, anhand derer deutlich wurde, dass besonders die enzymatische Behandlung in den der Methanisierung vorgelagerten Prozessstufen weiterzuentwickeln ist. Polysaccharides of plant cell walls are of limited digestibility due to their cross-linking to lignin. In order to make the molecules available for the biogas process and thus increase the substrate utilization and process efficiency appropriate substances or techniques are needed. It was therefore the aim of this work to investigate the effects of different enzyme preparations in three digestion process stages. Selected energy plants with varying degrees of particle sizes (chopping lengths) were used as digester feedstock. Enzyme preparations for the different process stages were chosen by enzyme assays. The selected enzymes were added to the feedstock during the ensiling, directly before the biogas process or during the biogas process separate or in mixtures. Pre-treated substrates were subsequently digested in batch fermentation tests. Beside the biogas and methane yield the degradation degree of lignocellulose and the release of low molecular carbohydrates were investigated for evaluating the enzyme performance. Additionally, the swelling of lignocellulose caused by addition of water in a pre-hydrolysis process was examined as a method of pre-treatment, with generally positive results. The aim of an improved substrate conversion of maize and rye and thus an enhanced biogas production by enzymatic pretreatments was achieved. Scientific fundamentals regarding the impact of enzymes on biogas processes were established. Enzymatic pretreatments in process steps before methanation showed potential for further developments.

Im Genom des phytopathogenen Pilzes Fusarium graminearum konnten 24 Gene identifiziert werden, deren Proteinprodukte Homologien zu Cellulasen aufweisen. Die Transkription von zwei Exo- (cel6 und cel7A) und zwei Endocellulasegenen (cel7B und cel45) war über Cellulose und Weizenzellwand induzierbar, während Glukose in der Regel zu keiner Induktion führte. Die Transkription von drei der vier untersuchten Gene konnte auch während der Infektion von Weizenpflanzen nachgewiesen werden (cel6, cel7A und cel45). Eine Beteiligung dieser Cellulasen am Infektionsprozess ist daher wahrscheinlich. Der Transkriptionsfaktor ACEI ist an der Regulation von Cellulasegenen beteiligt. Das Gen dieses Faktors wurde im Genom von F. graminearum identifiziert, sequenziert und charakterisiert. Das Ausschalten des konstitutiv transkribierten Gens des Transkriptionsfaktors ACEI in F. graminearum führte auf Weizenpflanzen zu einer erhöhten Virulenz der Mutante im Vergleich zum Wildtyp.

In the 1960s an increasing number of occupational allergies in the detergent industry against the proteolytic enzyme Subtilisin were observed. In this context the high sensitization potential of enzyme dusts attracted attention. The present evaluation of literature data confirms that this is also true for cellulases. These enzymes--mostly of fungal origin--are frequently used in biotechnology. Several cases of specific airway sensitization caused by cellulases are verified by a number of studies. As symptoms, results of skin prick tests, detection of specific IgE-antibodies and results of specific bronchoprovocation tests are consistent, an immunologic mechanism seems to be confirmed.

The efficiency of beta-glucanase or xylanase containing enzymes supplemented to rations for laying hens on the basis of barley-rye and wheat-rye were tested in two balance experiments. Five diets for eight hens each (White Lohmann Leghorn Hybrids) have been proved. The balances were carried out in the 23rd and 29th week of life. Statistically significant differences in the digestibility of nutrients like protein, fat and starch as well in the transformation of gross energy and metabolizable energy appeared especially in the first balance period. In the second balance period the starch digestibility was increased significantly from 93.7% to 99.7% by enzyme supplementation of the barley-rye rations. A positive influence of enzymes on the ileal digestibility of starch and fat could also be found. The addition of enzymes led to a decreasing reaction of the viscosity in the feed, in the different parts of the digesta and in the excreta.

In three trials with a total of 4120 male and female broilers, kept on floor or in cages maize has been partly replaced by barley, rye or triticale and different combinations of enzymes were fed. The supplementation of cellulases with mainly glucanase in barley based diets has had no significant influence on growth performance. In case of diets with 20% rye the addition of cellulases with mainly hemicellulases resulted in 5% higher live weight gains and a better feed efficiency (5%) on average of two trials. The negative influence of rye feeding on excrement constitution was lowered and the dry matter content of excrements increased by 1.3%. In diets based on triticale the growth performance of broilers was insignificantly better. The addition of enzymes did not influence the proportion of different body fractions as well as the crude nutrient content of edible carcass.

It could be shown that extracts of growing cultures of Acanthamoeba castellanii contained a cellulose degrading system. Reducing sugars are split off by one component of this system at an optimum of pH 4, another enzyme changes the viscosity at an optimum of pH 6, and a third component is a beta-glucosidase with an optimum at pH 3.5. At pH 4 the cellulose degradation products are cellobiose and glucose; at pH 6 higher molecular weight oligosaccharides are produced. During the development from trophozoites to cysts in a nutrient-free medium, the activities of both cellulases decline: Prior to the start of cellulose synthesis only 30%, and in cysts only 10% of the original existing activities are detectable. The biological function of the cellulase enzyme system is discussed together with a consideration of the fact that excystment takes place without digestion of the cyst wall in which the cellulose is deposited.

Several strains of Pseudomonas aeruginosa were investigated for pathogenicity to plant tissue. Inoculations into the intercellular spaces of leaves of Vicia faba (28 degrees C) and Vinca rosea (36 degrees C) showed negative results. In leaves of Nicotiana tabacum (32 degrees C) the bacteria multiplied; the tissue reacted to form partial lesions and necrosis. Neither in culture filtrates of the bacteria nor in eluates of inoculated leaves pectolytic and cellulolytic enzymes or breakdown products of these could be obtained. Whilst the proteolytic activity was high, symptoms for effects on the plant tissue, however, were not observed. Although this bacterium may be able to multiply after injection into tobacco leaf, the general question about pathogenicity to plants must be denied.

The ability of 5 aquatic Hyphomycetes to produce Amylase, Pectinase and Cellulase was investigated. All the tested strains were weak producers of Amylase and good producers of Pectinase, whereas degradation of Cellulose was only found with two strains.

A new highly effective enzyme-substituting product (Combizym forte) was tested clinically on 62 patients suffering from digestive insufficiency to ascertain the improvements of the complaints pain, nausea, meteorism, diarrhea and obstipation as well as the tolerance. 88,7% of the cases were free from complaints within about 14 days of treatment. Three patients had diarrhea; no other sidereactions were observed. Apart from the high enzymatic activity of Combizym forte, the absence of Fel tauri is noteworthy as it allows to increase doses considerably. The demonstration of the therapeutic action of Combizym forte by examinations of the stools and enzyme-chemical measurements will be the subject of another series of tests (2nd information).

With several isolates of T. aquaticus rotund bodies (rbs) have been artificially induced. The most active agents were lysozyme, pronase (not trypsin), cellulase (not alpha-amylase or beta-glucosidase), penicillin and some mineral salts. Two modifications of rbs were observed: the vesticular type arising from single cells or filaments and the aggregate-rbs resulting from secondary associations of several cells or filaments. In both cases the primary event is a partial detachment of the outer layer of cell envelopes followed by its swelling to form a hyaline bleb. Within these osmotically stable blebs cells and/or filaments involved in the ribs production become irreversibly trapped. Appearance of filaments and rbs in stationary phase cultures are discussed as a consequence of unbalanced growth culminating in abnormal autolytic reactions.

In a female patient anaemia due to chronic blood loss occurred after gastrectomy and subsequent vagotomy. Gastroscopy showed a phytobezoar to be the cause. In a second patient who had not had gastric surgery a phytobezoar was found as well as a prepyloric ulcer during investigations for upper abdominal symptoms. In both cases the phytobezoars could be removed completely within a short time after dissolution by an oral cellulase containing enzyme preparation and gastroscopic breaking-up.

Experiments concerning tumor transformation of plant cells or protoplasts need complete knowledge of the effects of media components. Here inhibiting effects of cellulase Onozuka, glucose, sucrose and mannitol (up to 0.3M), of tissue culture media, and of the antibiotic aureomycin on the tumor initiation process in Kalanchoe leaves are reported. Also the influence of these substances on the growth of the tumor inducing Agrobacterium tumefaciens is studied. The results lead to the design of conditions which should be favourable to in vitro transformation.

Summary 1. The addition of 0.2 M phosphate buffer to a culture of Rhizoctonia solani cultivated in a liquid medium prevents the usually observed increase of pH above the optimum for polygalacturonase-(PG) and cellulase-(Cx)synthesis, thus increasing the activity of both enzymes. The maximum enzyme activity in still cultures incubated at 27°C is reached at about the 13th day. The activity of both enzymes remains nearly at the same level for a longer period; therefore, the results of comparable enzyme experiments are only little influenced by the point of time at which enzyme activities are determined. 2. The highest PG-activity is observed when the fungus is grown on pectin-containing media, whereas the optimum Cx-activity develops on carboxymethylcellulose. In both cases addition of larger amounts of glucose to the media causes a decrease of the enzyme activity accompanied by a simultaneous increase of the weight of the mycelium. 3. The enzyme activity detectable in a liquid medium containing pectin and carboxy-methylcellulose and the dry weight of the mycelium depend decisively on the preculture of the inoculum. The best medium proved to be malt agar supplemented with a decoct of bean seedlings. Preculture of the inoculum in a medium containing pectin and cellulose results in the lowest values probably due to the scarce development of mycelium on this medium. 4. The pathogenicity of the fungus as evaluated by the rate of maceration of plant tissue is highly influenced by the preculture analogous to the enzyme production.