Structured lipids with n-6/n-3 polyunsaturated fatty acids (PUFA) or medium chain fatty acids (MC) at optimal ratios were prepared by lipase catalyzed transacylation of tuna orbital oil consisting of about 40% n-3 PUFA such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) with purified linoleic acid or MC, such as caprylic, capric, and lauric acids, at 60 °C. 1, 3- Specific immobilized lipases of Lipozyme TL-IM and Lipozyme RM-IM originated from Thermomyces lanuginosus and Rhizomucor miehei were used in the preparation, respectively. By controlling enzyme amount from 20-80 IUN for Lipozyme TL-IM and 1-12 BAUN for Lipozyme RM-IM with reaction time from 4 to 24h, structured lipids at n-6/n-3 ratios from 1.3 till 6.9 were easily prepared by the reaction of tuna orbital oil with highly purified linoleic acid. MC was introduced into tuna orbital oil at various MC/n-3 PUFA ratios such as 0.67-1.89 for caprylic, 0.73-2.85 for capric, and 0.91-4.08 for lauric acids, respectively during transacylation for 32 h. Lipozyme RM-IM was clearly shown a better enzyme for the present transacylation, compared to Lipozyme TL-IM in consideration of the above ratio values and triglycerides recovery.
Polyglycerol fatty acid monoesters are used widely as food emulsifiers, and conjugated linoleic acid (CLA) has various physiological activities. Hence, production of polyglycerol CLA monoester was attempted through a lipase-catalyzed reaction. A commercially available free fatty acid mixture (referred to as FFA-CLA) containing 9cis,11trans (9c,11t)-CLA and 10t,12c-CLA was used as a source of CLA, and its esterification with diglycerol was studied. Screening of several lipases showed that Penicillium camembertii lipase was suitable for production of diglycerol fatty acid monoesters (DGFAMEs). When a mixture of FFA-CLA/diglycerol (1:2, mol/mol), 100 U/g-mixture of the lipase, and 2% water was agitated at 30 °C for 24 h with dehydration at 5 mm Hg using a vacuum pump, the degree of esterification reached 93%, and the ratio of DGFAMEs/diglycerol fatty acid diesters was 1.9:1 (wt/wt). The synthesized DGFAMEs were purified to 97% in a 69% yield by short-path distillation. This process comprising lipase-catalyzed esterification and short-path distillation may be effective for industrial production of an emulsifier for use in nutraceutical applications.
Photoactive evaluation for cosmetic pigments in sunscreen agents, such as zinc oxide (ZnO), titanium dioxide (TiO2), aluminium oxide (Al2O3) and tungsten oxide (WO3), was carried out by examining DNA damage using agarose gel electrophoresis. Photoinduced DNA damage occurred in the presence of pigments under either aerated condition or oxygen gas atmosphere in the following order: WO3 ≈ Al2O3 ≈ rutile TiO2 < anatase TiO2 « TiO2 (P-25) « ZnO. The photoinduced oxidative activity of various pigments was assessed by the aromatic cleavage rate of phenol as a standard, which corresponds to the degree damaged to the supercoiled configuration of DNA (transformation to the linear form and/or relaxed form). L(+)-ascorbic acid (anti-oxidizing agent) can suppress the formation of photooxidative species such as ·OH radicals and/or ·OOH radicals. DNA damage under UV irradiation even in the presence of highly photocatalytic ZnO pigment was controlled by addition of the anti-oxidative enzyme catalase. DNA damage was depressed with increasing quantity of catalase.
A series of optically active 1,4-aminoalcohols were synthesized from the corresponding lactones, which were prepared from (+)-camphor and (-)-fenchone, via hydroxy amides. The addition reactions of diethylzinc to aldehydes using the 1,4-aminoalcohols as chiral catalysts were investigated. 1,4-Aminoalcohol catalysts derived from (+)-camphor resulted in secondary (S)-alcohols as the major product. The 1,4-aminoalcohols bearing two propyl groups achieved the highest enantioselectivity; the enantiomeric excess was 95%. 1,4-Aminoalcohol catalysts derived from (-)-fencone resulted in secondary (R)-alcohols as the major product. In the chiral 1,4-aminoalcohols from (-)-fencone, the alcohol containing a morpholine structure appended to the amino group possessed the highest enantioselectivity; with an enantiomeric excess of 79%.
Although trans geometric isomers of unsaturated fatty acids are formed during heat treatment, little is known about the physicochemical properties and the bioactivities of trans eicosapentaenoic acid (TEPA). We examined the oxidative stability and the anti-inflammatory activity of TEPA prepared using p-toluenesulfinic acid. TEPA was more stable to oxidation induced by radical generators than eicosapentaenoic acid (EPA) in organic and in aqueous solutions, and was less suitable as a substrate for 15-lipoxygenase oxidation than was EPA. These results suggest that the trans conformation may be a more stable structure to oxidation. In addition, the release of leukotriene B4 (LTB4) from Ca-ionophore-stimulated rat peritoneal exudate cells (PEC) was not affected by treatment with TEPA, and TEPA was taken up into PEC at lower levels compared to EPA. These results suggest that dietary TEPA has different physiological effects than EPA.
Free radicals and related species derived from O2 such as superoxide anion radical (O2-·), hydrogen peroxide (H2O2), hydroxyl radical (·OH) and peroxynitrite ion (ONOO-) are often generated in organisms with possibly consequent diseases. The enzyme, superoxide dismutase (SOD), catalyzes the reaction which eliminates O2-· As models of SOD, manganese porphyrins such as [meso-tetrakis(N-methylpyridinium-4-yl)porphyrinato] manganese(III) (MnT4MPyP) have been investigated. However, the half-life of any one of these in the blood is usually quite short. We undertook the design of a novel hexameric manganese porphyrin (HexMnP) capable of remaining for a prolonged period in the blood. The SOD activity of HexMnP (IC50 = 2.1 ± 0.7 μM) was found to be somewhat less than that of MnT4MPyP (IC50 = 0.71 μM), but to exceed that of reconstituted hemoglobin (MnT4MPyP-Hb) (IC50 = 2.0 μM) prepared in a previous study. HexMnP proved to be an effective SOD model in which HexMnP had the capacity to remain over a long period of time in the blood, owing to its molecular diameter of more than 80Å.