Regioselektive C-H-Funktionalisierung von Fettsäuren und Fettsäuremethylestern

Regioselective C-H-Functionalization of Fatty Acids and their Methyl Esters Fatty acids and thier methyl esters can be chlorinated preferentially at the terminal methylene groups with N-alkylchloroamines in sulfuric acid. With capric acid and its methyl ester the optimal reaction conditions for the selective chlorination were elaborated and then transferred to longer fatty acids up to stearic acid. The influence of the solvent, the temperature and the nature of different chlorinating reagents on the selectivity was studies. The capillary GC/MS-analysis of the isomeric chlorinated fatty acids is described.     

Einfluß der Konfiguration der Fettsäuren auf die Eigenschaften von Seife

Effect of Fatty Acid Configuration on the Properties of Soap The effect of configuration of the hydrophobic chain of fatty acids C₁₀–C₁₈ on the properties of their alkali salts was studied. Furthermore, the effect of temperature on critical micelle concentration (CMC) and on alteration of surface tension at CMC, as well as the effect of chain length of the hydrophobic part on CMC were determined. At the same time, the effect of double and cis-trans configuration on CMC was studied. Also the foaming ability of the individual soaps and foam stability as well as the stability of the soaps were investigated.     

Einfluß von Futterfetten auf die Qualität tierischer Veredlungsprodukte

Effects of Feed Fats on Quality of Animal Product At the same level of energy supply intake of fats/oils do not lead to a higher fat deposition in the carcass. Additionally, fats are carrier of fat soluble vitamins A, D, E, K and improve their absorption from the intestinal tract. The fatty acid profile of fat deposited in the organism, as for example in egg yolk is influenced by the intake of fatty acids provided by feed. This especially concerns linoleic- and linolenic acid as well as lauric- and myristic acid, High contents of polyunsaturated fatty acids negatively influence oxidative stability as well as consistency of body fat and therefore quality of animal products. An improved oxidation protection can be carried out by supplementation of antioxidants. Medium-chain, saturated fatty acids reveal positive effects on both criteria.     

Einfluß von zusatzstoffen auf die wärmestabilität von auf PVC basierenden systemen

The instability of systems on PVC basis may be attributed to physical and chemical phenomena. The stability of the system is basically influenced by the oxidation stability of the plasticizers. The volatility loss in plasticizer is only partially due to physical processes. During ageing, oxidation and degradation processes take place to a minor or major degree, or exclusively, depending on the structure of the plasticizer. These processes may be affected in their order of magnitude by the stabilizers and fillers present in the system.     

Über den Einfluß von Sonnenblumen-Krankheiten auf das Samenöl und auf die Veränderungen der freien Fettsäuren

Influence of Sunflower Diseases on the Seed Oil and on Changes in Free Fatty Acids The relationships between the widespread sunflower diseases like peronospora, botrytis disease, etc. on reduction of yield as well as on the deterioration of the quality of oil were investigated. It can be seen from the results obtained that the damage caused by such diseases can be minimized by suitable measures like dressing of the seeds, appropriate nutrition, proper sequence of planting etc. However, the breeding of resistant varieties remains an important task. Promising results were obtained in this respect by the author on the basis of an artificial infection procedure carried out in pathological breeding grounds.     

Einfluß von Schwermetallionen in Trinkwasser auf die Aktivität des AChE-Biosensors

Influence of Heavy Metal Ions in Drinking Water on the Activity of the AChE-Biosensor Because of the specific inhibition of the enzyme acetylcholinesterase (AChE) by organophosphoric ester, -thioester and N-methylcarbamates an acetylcholinesterase biosensor can be used to screen drinking water for the presence of compounds used as insecticides. The presence of heavy metal ions may also lead to a decrease in catalytic activity of the enzyme, and in this way a misinterpretation of the results of the screening is possible. In this paper the effect of lead, iron, copper and zinc ions on the activity was examined, with the view to the concentration limit given by the decree for drinking water in the Federal Republic of Germany. Zinc and copper ions in drinking water produce a detectable inhibition (3 mg/L copper produced an inhibition of 10 to 20%, 5 mg/L zinc an inhibition of 10%), therefore the presence of copper, lead and other heavy metal ions not tested in drinking water may produce wrong results in pesticide screening. The coimmobilization of albumin and enzyme was successfull in eliminating the inhibition caused by heavy metal ions. Using this membrane for a 3 mg/L copper solution an inhibition of only 0.3% higher was measured and for a 5 mg/L zinc solution an inhibition of 2.3% lower than the inhibition of TRIS-buffer itself. This results were in the range of the standard deviation, which means that no inhibition could be measured with this metal ion solution using albumin containing AChE-membranes. The use of this modified membrane in real drinking water samples shows clearly lower inhibition values than that of membranes without albumin.     

Der Einfluß der Chloroplasten auf die Bildung von ungesättigten Fettsäuren in reifenden Rapssamen

Influence of Chloroplasts on the Formation of Unsaturated Fatty Acids in Maturing Rapeseeds In general, seeds that store fats, contain only C₁₈-fatty acids which are desaturated upto linoleic step. Exceptions to this general pattern are the seeds of cruciferae, legumenae and linaceae. Embryos of these seeds develop, especially during the initial stages of maturation, photosynthetically active chloroplasts with a high content of linolenic acid. Therefore, for the breeding of rapeseed plants (cruciferae) having low linolenic acid content in the seed oil, one has to select either such seeds in which very little chloroplasts are formed during maturation, or seeds in which chloroplasts are reduced at an early stage.     

Einfluß der Bleicherde auf die Fettsäurebildung während der Bleichung

Effect of Bleaching Earth on the Formation of Fatty Acids during Bleaching Investigations were carried out with neutralized soybean and cottonseed oils in order to determine the effect of acid content of bleaching earths with different activities on the formation of free fatty acids during the adsorptive bleaching. The free fatty acid content of the oils under investigation decreased with increasing acidity of the highly active and moderately active bleaching earth. The increase in acid value of the oil during bleaching is essentially dependent on the duration of bleaching and amount of bleaching earth employed. The water content of the oil has no decisive effect.     

Neue Fettderivate aus der Esterkondensation von Fettsäuremethylestern

New Fatty-Derivatives from the Ester Condensation of Methyl Esters of Fatty Acids The preparation of products of ester condensation from methyl esters of fatty acids is discussed and the chemistry of the derivatives as well as the possibilities of their application is reported.     

Der Einfluß stereoisomerer und konjugierter Fettsäuren,insbesondere dehydratisierter Rizinusöl-Fettsäuren,auf die Eigenschaften von Alkydharzen

The Influence of the Stereoisomeric and Conjugated Fatty Acids, Especially Dehydrated Castor Oil Fatty Acids, on the Properties of Alkyd Resins Alkyds with 60% oil content were prepared from the drying oils with different contents of conjugated and stereoisomeric fatty acids, specially dehydrated castor oil, and the autoxidation and film forming properties of these were investigated. Trans-trans-dienoic fatty acids oxidised fastest but hindered the through-drying. Throughdrying is dependent on this hinderence and the total content of conjugated dienoic fatty acids. The hardness of the film, measured after 7 days by Sward-Rocker method, is a function of the total amount of conjugated and nonconjugated polyunsaturated fatty acids.     

Einfluß der chemischen Struktur auf das Luftabscheidevermögen und die hydrolytische Stabilität von Estern

Influence of the Chemical Structure in Regard to the Air Release Properties and the Hydrolytic Stability of Esters Esters, based on fatty chemical basis, are of great importance for the lubricant industry as efficient, biodegradable basestocks and additives. The structure possibilities and synthetic variations of ester oils are described. Basic datas are presented inclusive application areas. Parameters like air release properties and hydrolytic stability possess a central function in special applications like hydraulic fluids or compressor lubes. Oil dispersed air bubbles influence the compressibility and can cause disturbances in oil containing systems. Esterhydrolysis by water are followed by precipitation, decompositions and increased corrosivity. The determination of the air release according DIN 51 381 and the hydrolytic stability leanded against ASTM D-2619 are explained. A great number of esters based on primary and polyhydric alcohols in combination with branched and unbranched, saturated and unsaturated mono- and dicarboxylic acids were tested. Structure-effects rules were fixed in dependence of viscosity, iodine value, branching degree and carbon chain length in order to improve the choice of esters for synthetic oils.     

Der Einfluß von Anion- und Kationtensiden auf die chemische Reaktionsfähigkeit von Wolle

Influence of Anionic and Cationic Surfactants on the Chemical Reactivity of Wool The alkaline degradation of cystine in wool is diminished by anionic detergents and increased by cationic detergents. The reaction with sulphite is influenced in a similar manner. In acidic media, the opposite effect is exerted by ionic detergents on the acid hydrolysis of wool peptide bonds; hydrolysis is enhanced by anionic detergents and diminished by cationics. Nonionic detergents are without any effect on the chemical reactivity of wool. The results are explained in terms of changes in electrical charges on the fibre surface, due to adsorption of detergent ions.     

Der Einfluß der Umwelt auf Fettgehalt und Fettsäuremuster verschiedener Sonnenblumensorten

Environmental Effect on Fat Content and Fatty Acid Pattern of Different Varieties of Sunflower Crude fat content and fatty acid composition have been determined for two years on experimental crops of 8 and 15 varieties respectively of sunflower grown in two different locations in Central Europe and of one variety grown in East Africa. Crude fat content in fruits varied in the different locations (29% in Mozambique compared to 35% in Europe) and also from variety to variety (24.3% upto 45.1%). No correlation existed between the fatty acid composition and oil content. A distinct negative relationship was found between the linoleic and oleic acid content (r = –0.931). Under cold growth conditions an increase in linoleic acid content and a decrease in oleic acid was observed. Under dry and warm conditions during the short days at Mozambique, the level of linoleic acid was 46% compared to 72 in Europe. The corresponding values for oleic acid were on average 17% in Europe and 44% in Mozambique. Certain variational differences were observed, however, only to minute extent compared to locational differences.