The effects on the lipid composition of Fusarium moniliforme with growth age using glucose or decane as the carbon source was investigated. It was found that the maximum dry weight of growth cells and accumulation of lipids in mycelium at 30°C was attained in 2 days using glucose and 6 days of culture using decane respectively. The neutral and polar lipid fractions in the cells grown on decane mainly contained linoleic acid (4560%) which increased gradually during incubation. The neutral and polar lipid fractions in the cells grown on glucose contained oleic acid (ca. 40%) and linoleic acid (ca. 30%). Changes in neutral lipid composition and the amount of sterol in the cells grown on glucose or decane with regard to culture aging were also studied.
Various fats and oils (2ml) were tested for their reaction with Bieber's reagent (10ml), a mixture of equal weights of sulfuric acid, fuming nitric acid and water. This is the so called Tsujimoto's color reaction. Blue green colors were observed for camellia oil, sasanqua oil, olive oil and high oleic safflower oil. Also solid fats such as coconut oil, palm oil, and beef tallow were found to turn blue green. Other oils turned yellow or orange. This coloration was related to the ratio of the content of polyenoic fatty acid to that of monoenoic fatty acid. That is, the ratio at which the blue green color appeared was below about 0.25 for liquid oils, but below about 0.35 for solid fats. This color reaction makes possible the easy identification of fats and oils of high monoenoic fatty acid content (70%>).
To establish a standard color detection method, various color reactions for detection of kapok and cottonseed oil present in other oils were examined. Good detection was possible by the Halphen reaction and satisfactory results were also obtained by Besson, Milliau, and Becchi & Milliau reactions using silver nitrate. About 0.01% crude kapok oil or 0.1% neutralized cottonseed oil in soybean oil could be detected by the Halphen reaction. By the three reactions using silver nitrate, it was possible to detect nearly 0.5% crude kapok oil or 5% neutralized cottonseed oil. These results indicate that the Halphen reaction is the best method for color detection because of its high sensitivity, while the Besson reaction rates second in view of the simplicity of the procedure.
Tertiary-butyl methyl ether (MTBE) has recently attracted much attention as a high-octane blending stock in the preparation of unleaded premium gasoline. The biodegradation study of several alkyl ethers having various alkyl groups was carried out by measuring the oxygen uptake rate in the presence of standard activated sludge as a source of microorganisms. Although alkyl ethers with t-butyl groups in their molecules showed very poor biodegradability (Fig.-1), MTBE had no effect on the biodegradability of gasoline blended with it (Fig.-2). MTBE-blended gasoline was found to have excellent biodegradability and causes no environmental pollution. The bioconcentration factor in fish was determined by the cultivation of Japanese carp in a flowing water system containing alkyl ethers over a period of four weeks. Alkyl ethers used in this bioconcentration experiment were 2- (t-butoxy) ethanol, MTBE, and t-butyl isopropyl ether. The bioconcentration factors of these ethers were 0.6, 1.5, and 5.7, respectively (Fig.-3, Table-1 and Table-2). The concentrated MTBE in the fish was excluded quite rapidly on placing the fish in fresh water (Fig.-3). The bioconcentration factors of water-soluble chemicals such as the alkyl ethers used in this experiment, can be predicted from their partition coefficients in an 1-octanol-water system (Fig.-4).