The oxidative decomposition of t-butylated hydroxyanisole (BHA) and formation of its dimers were investigated during the thermal oxidation of saturated and unsaturated triglycerides.
Glycerol trilinoleate, in which BHA had been dissolved, was oxidized by air at 150°C to obtain two oxidation products of BHA from the reaction mixture by extraction with acetonitrile and silicic acid column chromatography. They were identified as the diphenyl ether type dimer and biphenyl type dimer of BHA by 1H-NMR and mass spectroscopy. The isomers of the BHA dimer and BHA monomer in oxidized triglycerides were determined by HPLC, using LiChrosorb SI-60 as the stationary phase, hexane-diisopropyl ether mixture (9 : 1) as the mobile phase, and a UV monitor (290 nm).
Changes in the concentrations of BHA and its dimers during the thermal oxidation of glycerol trilaurate and glycerol trilinoleate were followed by HPLC. In glycerol trilaurate, BHA was oxidized to give its dimers. The total quantities of BHA and its monomer showed little decrease. It is thus apparent that BHA dimers undergo only slight oxidative decomposition in saturated triglyceride. A considerable decrease in BHA concentration was observed in glycerol trilinoleate, and the total quantities of BHA and its dimers were less within the time tested than those in glycerol trilaurate. In the saturated triglyceride, a diphenyl ether type dimer predominated, but in the unsaturated triglyceride, a biphenyl type dimer was larger, indicating reversal of relative composition.

View full abstract

The synergistic antioxidant effects of tocopherols (Tocs) and extracted components from clove on lard and palm oil were investigated by oven and AOM tests. From the components obtained, powdered commercial clove was extracted with petroleum ether (PE) and ethanol (EtOH) followed by fractionation of the EtOH extract through solubilization in hexane and silica-column chromatography. The antioxidant effects of them were also studied in the same manner.
1) Both of PE and EtOH extracts of clove clearly showed antioxidant effects on lard by addition at 0.2%, the effect of the latter being stronger.
2) The hexane soluble component above the EtOH extract also showed antioxidant effect, and somewhat enhanced the effect of a mixture of d-Toc (m-Toc) on lard. The insoluble component enhanced synergistically the effect of m-Toc by hindering increase in POV during the induction period.
3) Such effects as those of the above soluble component were observed at 500ppm or more of eugenol, the main effective constituent of clove a spice. However, at 100ppm with the addition of acetyl eugenol, and analogous constituent, no effect was observed.
4) No extracted component of clove such an inhibitory effect on the oxidation of palm oil.

View full abstract

An investigation was made of the decomposition of longifolene oxide (1), isolongifolene oxide (2) and β-caryophylene oxide (3) with formic acid in the presence of synthetic zeolites (3A, 4A, 5A, 13 X, TSZ-320-REA, TSZ-330-HUA, TSZ-330-HSA, TSZ-600-HOA, TSZ-640-HOA and TSZ-640-NAA). With formic acid in 4A synthetic zeolite, the decomposition of (1) gave longicamphenilone (4) with high selectivity (86% at optimum).
With formic acid in the presence of 13 X synthetic zeolite, isolongifolane-4-on (8) and isolongifolane-4-ol (9) were obtained as principal components from (2). The decomposition of (3) gave tricyclic compounds such as dihydroclovene-5-ol (14) as the major products.

View full abstract

The addition of ethylene oxide (EO) to N- (perfluoroacyl) ethylenediamine (N F) in the presence of R_f =n-C₃F₇ or n-C₇F₁₅ in benzene was carried out at 50130°C in an autoclave without catalysts. The addition reaction proceeded easily and stepwise to yield 1 : 1 and 2 : 1 adducts at low temperature. There products were isolated and measured by gel permeation chromatography. The rate of addition was higher at higher concentration of EO. When the reaction was carried out at [EO] / [NF] =12 at 8090°C for 5 hours, yield of the 2 : 1 adduct was 98%.
Above 90°C, the marked formation of byproducts occurred.
The surface activity of the adduct with R_f =n-C₇F₁₅-was found better than that with R_f =n-C₃F₇.

View full abstract

This paper describes the adsorption properties of humic substances onsurface-treatedcarbon adsorbents in aqueous solutions including inorganic compounds. Activated carbon fiber made from phenol resin (ACF), Pittsburgh activated carbon (AC) and Electronic conductive carbon black (EC) were used. The solution behavior of humic substances varied due to the presence of certain inorganic compounds. When the valence and/or concentration of the inorganic compounds increased, lower molelcular-weight components (M.W. 1001, 000) in humic substances were converted to higher molecular-weight components (M.W. 1, 0003, 000) due to aggregation. The adsorbed amounts of higher molecular-weight components (M.W. 1, 0003, 000) was larger by using EC with a large volume of meso-pores than by using ACF and AC being rich in micropores.

View full abstract

Coal-water mixtures (CWM) are usually sheared at different rates by pumping, atomization and other steps in proceeding from production to combustion. Thus. a through knowledge of their rheological characteristics in advance is important for determining the most appropriate handling procedure. The authors examined CWM samples of various coal concentrations, and obtained the following results.
1) CWMs containing no additives are Newtonian fluids, at a coal concentration less than 10%.They became pseudo-plastic fluids on increasing the coal concentration.
2) Two highly loaded CWMs, one with a multi-branched high molecular nonionic surfactant and the other with the sodium salt of the formalin naphthalenesulfonate condensate, showed pseudoplastic flow.
3) For both types, on bringing the coal to a certain concentration, pseudoplasticity suddenly increased. At a lower coal concentration, CWM containing a nonionic surfactant was rapidly converted to Newtonian fluids. CWMs possessing an anionic surfactant gradually lost pseudoplasticity.
4) A CWM showing pseudoplasticity at a low coal concentration can be produced from coal with high oxygen content.

View full abstract

Lipid peroxides, which are mainly hydroperoxides, contained in 1mL of human serum could be determined accurately under ice-cooled condition by potentiometry used with an automatic titrator.
The average values per 1 mL of sera of 105 healthy males in their twenties were 25.3±14.3 neq for peroxides and 2.32 ± 0.86 nmol for TBA, respectively. TBA values for various sera showed the equivalent of only ca. 20% on the average for peroxide content determined by potent-iometry. However, there was no relationship between potentiometric peroxide levels and colorimetric TBA values due to the large coefficient of variation in detection ratio of peroxides by TBA method, where the ratio was calculated as x mol peroxides for TBA divided by y mol peroxides obtained from the potentiometry, i, e., x/y.
Also is discussed the influence of the levels of iron compounds or polyunsaturated fatty acids (PUFA), which are the constituents of lipids, present in various sera samples upon the lipid peroxide content, TBA values or detection ratios of peroxides by TBA method.
Iron compounds in serum were found to have no catalytic effect on the accumulation of lipid peroxides in vivo and TBA measurements since their amounts were so small. The levels of lipid peroxides were independent of PUFA content but the detection ratios of peroxides by TBA method depended on the content in each serum sample.

View full abstract

Two new methods have been devised for the biotransformation of dehydroabietic acid (DHAA). The first involves incubation of suspension callus tissues from Daucus carota in Murashige and Skoog's medium containing sucrose, 2, 4-dichlorophenoxyacetic acid and DHAA to give 16-hydroxydehydroabietic acid. In the second method, incubation of suspension callus tissues is carried out in the medium containing no DHAA, followed by the administration of an aqueous NaOH solution of DHAA to yield 7-oxodehydroabietic acid.

View full abstract

Two new triterpene alcohols separated as a mixture from the unsaponifiable lipid of a stem extract of Neolitsea sericea were identified as (24 E) - and (24 Z) -24-ethylidenecycloartanols.

View full abstract

The title reaction was carried out with α-pinene oxide, α-campholenaldehyde and carvone were found to be produced at high selectivity using chromic acid adsorbed on to silica gel (H₂CrO₄/SiO₂) and on alumina (H₂CrO₄/Al₂O₃), respectively.

View full abstract

While assaying lipase with emulsified substrate, an investigation was made of the stability of the substrate and coefficient of variation (C.V.) affected by the lot and mixing ratio of poly (vinyl alcohol) (PVA) using Mucor lipase and Rhizopus lipase.
The residual activity of lipase (represented as relative activity against the value assayed immediately following substrate preparation) in the use of [PVA 117+PVA 205] was for Mucor lipase, 92.5% and for Rhizopus lipase, 100%. This shows the substrate to be essentially stable. Whereas the residual activity when using PVA 117 to be 67% and 80% respectively. Thus, the substrate is unstable.
C.V. 96 h after the substrate preparation gave a higher value than that assayed immediately following substrate preparation in both [PVA 117+PVA 205] and PVA 117. C.V. of the former PVA (below 10) was lower than that of the latter PVA (above 10). Furthermore, the effect of PVA on C.V. differed according to the lipase.

View full abstract