Antioxidants comprise a major group of food additives. However, BHA and BHT as synthetic antioxidants are suspected of beeing toxic in character so that natural antioxidative compounds, particularly those from plant materials, should take the place of synthetic compounds. This paper reports the isolation, identification and estimation of a natural antioxidant in grape seed extracts. The natural antioxidant, III, obtained in crystalline form from the extracts with ethyl acetate of grape seeds by centrifugal chromatography, using Wakogel B-O as a packing material. Antioxidative activity was determined by AOM in lard. This antioxidant showed remarkable antioxidative activity toward lard and was more effective than dl-α-tocopherol, BHT and BHA. Its main components were identified by UV, IR, MS and 1H-NMR as (+) -catechin and (-) -epicatechin.
Methods for quantitatively estimating the composition of simple lipid and phospholipid mixtures were developed using alumina thin-layer chromatography-flame ionization detection systems. Simple lipid mixtures containing palmitic acid, cholesterol, tripalmitin and cholesterol palmitate, were separated on Chromarod A (alumina sintered rod) with double development to a distance of 6 and 10cm from the start, using benzene-ethylacetate (9 : 1) and n-hexane-benzene (9 : 1). A phospholipid mixture containing phosphatidylcholine, lysophosphatidylcholine, sphingomyeline, cardiolipin and phosphatidylethanolamine were separated on the rod employed with chloroform-methanol-water-15N ammonia solution-pyridine (65 : 27.5 : 4 : 2 : 2). Individual lipids separated on the rod were then automatically quantified by means of a hydrogen flame ionization detecter (Iatroscan). The relative responses of these lipids were found to be in proportion to the theoretical responses based on weight per cent. These responses converged with a maximum error of 510% (C.V.).
The physico-chemical properties of a series of monodispersed alkyl polyoxyethylene ethers were measured. The melting points of the samples increased in a zigzag manner with increasing alkyl chain length at a constant polyoxyethylene chain length, although the melting points of fatty alcohols increased linearly with increasing alkyl chain length. The refractive index increased with increasing polyoxyethylene chain length and alkyl chain length. The refractive index and hydroxyl value showed a linear relationships. The cloud point increased with increasing polarity (HLB, IOB, OH-V), but the cloud points of shorter alkyl chain samples were higher than those with longer chains at the same polarity.
To elucidate the influence of a conveyer attached to an auto-fryer on the deterioration of frying oil, the folowing experiments were carried out. 1. As a conveyer model, rotors were constructed to rotate slowly over the frying oil surface. A comparison was made of the degree of deterioration of soy bean oil heated for 8hrs at 180°C with and without the use of the rotors. Observation of the changes in viscosity, acid value and color of the oils showed that the rotors accelarated remarkably the deterioration of soybean oil. Coating of the rotors with Teflon or the use of net rotors in place of plate rotors significantly reduced the thermal deterioration of the soybean oil. 2. The influence of the vessel materials (aluminium and iron) coated with and without Teflon on the deterioration of soybean oil heated at 180°C was investigated. Deterioration was found to be less for vessels coated with Teflon.
A convenient synthesis of Muscalure (cis-9-tricosene) (3), the sex pheromone of house fly (Musca domestics L.), is described. Methyl 3-oxohexanoate (1) was alkylated with 1-chloro-cis-9-octadecene (oleyl chloride). The product, without isolation, was demethoxycarbonylated to give cis-14-tricosen-4-one (2). The desired compound (3) could be obtained by the Huang-Minlon reduction of (2).
The reaction of spiro [4.5] decan-6-one (1) with vinylmagnesium chloride gave 6-vinylspiro [4.5] decan-6-ol (2). The Carroll reaction of (2) with ethyl acetoacetate produced 5- (spiro [4.5] decyliden-6-yl) -2-pentanone (3). 2- (Spiro [4.5] decyliden-6-yl) ethanal (4) and 5- (spiro [4.5] decyliden-6-yl) -3-penten-2-one (5) were prepared from (2). The reaction of (2) with 3-hydroxy-1-butynylmagnesium bromide gave 4- 6-hydroxyspiro [4.5] decan-6-yl-3-butyn-2-ol (6).