Aquaculture was first affected by vitamin E problems associated with “Sekoke Disease” in carp fed dried silk worm pupae in Japan. Muscular dystrophy was the most marked clinical symptom and it was shown to be caused by the oxidation of the lipids in the feed. Addition of vitamin E in the diet prevented this disease and later studies showed that Sekoke Disease was related to vitamin E deficiency in the tissue. For carp fingerlings the α-tocopherol dietary requirement was 10 mg/100 g dry diet, for chinook salmon 0.53.0 mg, 25 mg for channel catfish, 17 mg for eel but only 2 mg for rainbow trout. However, these requirements are complicated by other factors such as the presence of selenium as a component of glutathione peroxidase, the level of polyunsaturated fatty acids (PUFA), the growth stage, tissue storage levels of vitamin E and likely the water temperature. In general, addition of 510 mg of α-tocopherol per 100 g of diet provided adequate protection for most cultured fish studied to date. Recently, vitamin E have been shown to be essential in reproduction and enhancement of the immune response in fish, although more detailed research is needed to clarify the mechanism of action of vitamin E in reproduction and immunity. Vitamin E is also important in maintaining the flesh quality of frozen fish.
A study was made of liquid phase oxidative cleavage of palm fatty acids and palm stearin into mono-and dibasic acids with middle carbon chains and their separation. Cobalt acetate used as a catalyst showed the highest activity in the oxidation of oleic acid. The optimum reaction temperature and oxygen pressure were 90°C and 30 kg/cm2, respectively. Under the conditions used, oleic acid was converted to dibasic acids and monobasic acids selectively. Oxidative cleavage of saturated fatty acids such as palmitic and stearic acid did not occur under the same conditions. Unsaturated and saturated acids in palm stearin were found to be oxidized in a stepwise manner at appropriate temperatures. The obtained products could be separated and purified, and the catalyst recovered by washing with hot water.
A method for quantitatively determining the surfactant component containing linear alkylbenzenesulfonate and alkylethoxylated sulfate as the anionic surfactant and alkylpoly (oxyethylene) ether as the nonionic surfactant, was devised using a two dimensional thin layer chromatography-extraction and densitometry. This determination method was carried as follows : The surfactant component was separated by two dimensional chromatography and each spot was extracted by a solvent. The amounts of surfactants were estimated from the optical density of the extracted solution. In the densitometry method, the spot on the thin layer plate was colored by charring. The illuminated area was scanned by a zigzag scanning type densitometer and the amounts of surfactants were estimated from spot integrated values. Recoveries of five replicated analyses for the two-dimensional thin layer chromatography-extraction method (sample 1.01.5 mg) and-densitometry method (Sample 0.140.22 g) were 93.5-97.9% and 99.6-100.4%, with the standard deviations being 2.63.194 and 1.42.4%, respectively. The extraction method has advantages in accuracy and simplicity of the procedure compared with densitometry. It thus appears that for the quantitative determination of surfactant components in detergent by thin layer chromatography, densitometry is superior to the extraction method.
The hydrolysis reactions of monoalkyl phosphate (MAP) and dialkyl phosphate (DAP) at high temperature were studied. The mono-anion of MAP was readily hydrolyzed at high temperature but the di-anion of MAP and anion of DAP to only a limited extent. The hydrolysis of sodium sesqui-n-octyl phosphate (SAP-08) at various degrees of neutralization (DN), a compound synthesized from the phosphorylation of octyl alcohol with phosphorus pentoxide, was studied in 48% aqueous solution at 145°C for 7 h. Under neutral conditions, the hydrolysis of SAP gave high purity dialkyl phosphate. The dianion of P, P'-dialkyl pyrophosphate (Py-1, 1) was found to be hardly hydrolyzed under neutral conditions while the pyrophosphate bond was readily so under acidic conditions. Extension to industrial production method of high purity DAP is also discussed.
The structural characteristics of water molecules on membrane microproperties of L-α-phosphatidylcholines were investigated by a fluorescence spectrometer. Polarity in the surroundings of the hydrophilic groups of L-α-phosphatidylcholine molecules in gel and concentric lamella phases, using a static fluorescence technique, considerably changed at a water content of about 20 wt%, and microviscosity decreased with increasing water content. Addition of urea to L-α-phosphatidylcholine-water systems changed the polarity and microviscosity in the surroundings of hydrophilic groups at a water content above 20 wt% probably due to change of structural characteristics of interlamella water. The present study suggests that the physicochemical microproperties of L-α-phosphatidylcholine bilayer are related to the structural characteristics of water molecules.