Journal of oleo science最新文献

Surfactants are amphiphilic substances that induce surface tension reduction, washing, and emulsification and are used for various purposes. Recently, biosurfactants manufactured from renewable resources and with high biocompatibility have gained increasing attention. Sophorolipid (SL), a type of biosurfactant derived from Starmerella bombicola, possesses detergency and emulsification properties, making it suitable for household and personal care applications. However, there are limited toxicological data on SLs. In this study, we conducted cytotoxicity and skin-irritation tests using SLs, revealing that cytotoxicity and skin irritation induced by SLs were extremely low (logIC ₅₀ = 4.76 mg/L) and equivalent to those of solvents and oils used in personal care products.

Many in vitro studies have revealed the toxic effects of oxidized phytosterols (OPSs); however, their effects on lipid metabolism are not well understood in vivo. Therefore, we examined the bioavailability of OPS and compared the effects of dietary phytosterols (PSs) or OPS on lipid metabolism in rats. OPS was detected in the plasma and liver of rats administered 50 mg of OPS for 3 days. Rats were fed the AIN76 diet (C group), basal diet plus 0.25% PS (P group), or 0.25% OPS (O group) for 4 weeks. Dietary OPS but not PS reduced hepatic fatty acid synthase activity. Liver triacylglycerol (TG) levels tended to be lower in the P group than in the C group and were significantly lower in the O group. The mRNA expression level of HMG-CoA reductase in the liver was the lowest in the O group, whereas that of CYP27A1 was the highest in the O group. The mRNA expression levels of NPC1L1 in the intestinal mucosa were significantly lower in the P and O groups than in the C group. Consistent with these modulations, plasma total cholesterol (TC) and HDL-C levels were similar between the C and P groups but tended to be higher or significantly higher in the O group. Liver TC levels were significantly lower in the P and O groups than in the C group. Moreover, fecal neutral and acidic steroid levels were the highest in the O group. The mRNA expression level of Δ6 desaturase in the liver was significantly higher in both the P and the O groups than in the C group. The Δ6 desaturation indices of fatty acids in the total liver lipids were the highest in the O group. Thus, dietary OPS may modulate lipid metabolism in the liver.

Scallop oil (SCO) prepared from the internal organs of the Japanese giant scallop (Patinopecten yessoensis) contains eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and phospholipids (PL). It was previously shown that SCO consumption improves cholesterol and triacylglycerols (TG) contents in mice. The present study demonstrated the effects of daily SCO consumption (1.2 g/day, containing 376 mg of EPA, 63 mg of DHA, and 150 mg of PL) for 12 weeks in human subjects. In this randomized, doubleblind, placebo-controlled, parallel group comparison study, 70 Japanese subjects with serum TG levels ≥120 but < 200 mg/dL were recruited and randomly assigned to the SCO or placebo group. All subjects ingested six capsules per day for 12 weeks. We conducted medical interviews, body composition measurements, vital sign examinations, and blood sampling at weeks 0 (baseline), 4, 8, and 12, and measured peripheral blood flow at weeks 0 and 12. In the case of subjects with higher serum TG levels, SCO consumption decreased the changes in serum TG and malondialdehyde-low density lipoprotein (MDA-LDL) levels compared with the placebo group. Safety assessment revealed no medically significant changes due to continuous SCO consumption. The findings indicate that 1.2 g/day of SCO consumption may be beneficial for reducing serum TG and MDA-LDL levels in persons with higher TG levels.

This study aimed to better understand the association between the amount of polyunsaturated fatty acids, namely, linoleic acid (LA) and linolenic acid (LNA), and the increases in the peroxide value that results from storing interesterified fats, which are used as sources of solid fats in edible oil and fat products, at high temperatures. Six interesterified fats with different LA and LNA contents were prepared and oxidized at 50°C, 60°C, 70°C, and 80°C under Rancimat test conditions. The oxidation rate increased with LA and LNA contents and increasing temperature. The oxidation kinetic analysis during the early oxidation stages demonstrated that when LA and LNA exceeded 8% and 2% respectively, the oxidative stability decreased as expected. However, the total LA and LNA contents had a higher correlation with the reaction rate constant [k (meq kg^-1 h^-1 )] than each amount of LA and LNA contained therein. In other words, the oxidation stability of the interesterified fats used in this study depended on the total LA and LNA contents.

Shape-controlled nanocrystals, such as nanoflowers, are expected to serve as innovative nanocatalysts with high catalytic activity. It is well-established that these nanocrystals can be readily synthesized with specific shapes using colloidal methods in solutions containing capping agents. However, these capping agents tend to reduce the catalytic activity of nanocatalysts. Therefore, it is imperative to remove these agents without altering the morphology to enhance catalytic efficiency. In this study, we developed a method for eliminating melamine, a common capping agent, from supported Au nanoflowers using water extraction and ultraviolet-ozone treatment. This process significantly enhances the catalytic performance, particularly for alcohol oxidation reactions such as the conversion of 1-phenylethyl alcohol to acetophenone.

Growing evidence indicates that the intake of trans fatty acids (TFAs) increases the risk of numerous diseases, such as cardiovascular diseases. Recently, our group found that certain natural sulfur compounds (allyl isothiocyanate [AITC] and diallyl disulfide [DADS]) promote cis to trans isomerization of fatty acid esters during heat treatment. However, little information is available on the fatty acid isomerization with them. In this study, we investigated the effects of oxygen and α-tocopherol (antioxidant) on isomerization of oleic acid (18:1) methyl ester (OA-ME) in the presence of AITC and DADS. Furthermore, the effect of the simultaneous use of AITC and DADS was evaluated. Our results indicate that oxygen enhances the AITC-induced trans isomerization, and DADS was found to promote trans isomerization but inhibit AITC-induced trans isomerization during heating. Both AITC- and DADS-induced trans isomerization were inhibited by α-tocopherol. These results indicate that the trans isomerization of fatty acids induced by sulfur compounds can be controlled by devising a cooking process and the food ingredients used together.

Recent global scientific attention has been directed towards eco-friendly synthesis and versatile applications of silver nanoparticles (AgNPs) due to their effectiveness against specific cells and tissues. This study aimed to develop a green synthesis method for AgNPs using ethanolic extract from Salvia sclarea aerial parts, and to assess their protective efficacy against streptozotocin (STZ)-induced diabetic nephropathy in rats. Additionally, antioxidant, anti-inflammatory, and apoptosis studies were conducted to understand their mode of action. Characterization via ultraviolet-visible (UV-Vis) spectroscopy, infrared (IR) spectroscopy, and X-ray diffraction (XRD) confirmed the formation of ethanol extract of Salvia sclarea silver nanoparticles (EESS AgNPs), with a distinctive absorption peak at 400 nm. Scanning electron microscopy (SEM) analysis revealed predominantly spherical and quasi-spherical shapes of the synthesized nanoparticles. The treatment procedure spanned for a period of 12 weeks in diabetic rats and were evaluated for inflammatory markers (tumor necrosis factor-α, antioxidant markers (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH) and apoptosis markers (Bcl-2, Bax, cleaved-caspase-3). Results demonstrated that treatment with EESS AgNPs significantly reduced blood glucose levels compared to the diabetic group. Additionally, EESS AgNPs treatment led to a significant decrease in levels of pro-inflammatory cytokines TNF-α, IL-1β, and PKC-ꞵ in renal cells. Furthermore, EESS AgNPs effectively modulated antioxidant enzyme concentrations, including GSH, SOD, GPx, and CAT, bringing them to acceptable levels. Administration of EESS AgNPs also resulted in a significant decrease in protein levels of Bax and activated caspase-3, while increasing expression of the anti-apoptotic protein Bcl-2 in renal cells of STZ-induced diabetic rats. In conclusion, EESS AgNPs demonstrate potent anti-hyperglycemic effects, potentially mitigating diabetic nephropathy by suppressing hyperglycemiainduced oxidative stress, apoptosis, and inflammation in renal cells of diabetic rats.

The essential oil extracted from the flower buds of Lonicerae japonicae (LJEO) was employed in the high-temperature (65℃) accelerated preservation of sunflower oil. In the present investigation, the addition of the essential oil at a concentration of 800 ppm significantly inhibited the decrease in the oxidative stability of sunflower oil. This positive effect was achieved by significantly hindering the reduction in acidity value (AV), peroxide value (PV), p-anisidine value (AnV), the total oxidation value (TOTOX) (p < 0.01), and the levels of thiobarbituric acid reactive substance (TBARS), the absorbance at 232/268 nm (K232/K268) and total polar compounds (TPC) (p < 0.01). Besides, it also significantly enhances the sensory attributes of Maye, including taste, flavor, and appearance, improving its overall acceptability through the addition of certain potential fragrance molecules (p < 0.01). Furthermore, one of the primary chemical compounds in LJEO, eugenol, has demonstrated significant natural antioxidant properties in the traditional deep-frying procedure for the product, Maye. Consequently, together with eugenol, the essential oil LJEO could be employed as a possible effective antioxidant for the typical long-term preservation and even the traditional deep-frying procedures, and developed as effective antioxidant extracted from plants for the whole food industry.

With increases in consumer demand for fried foods in Japan over the last several decades, the consumption of frying oil has also steadily increased. Fryers used in restaurants to cook large quantities of food are typically cleaned using neutral kitchen detergents at the end of the day after removing the oil from the tank. However, significant amounts of debris can remain in the fryer after cleaning, possibly accelerating oil deterioration and thus reducing the quality of the fried foods. In this study, debris obtained from fryer tanks used in actual restaurants was assessed using scanning electron microscopy-energy dispersive X-ray spectroscopy together with Fourier transform infrared spectroscopy, and were determined to comprise polymerized oil and carbonized organic matter. Experiments using artificially prepared debris confirmed that these materials increased the acid value (AV) of frying oil. Trials in two restaurants serving similar amounts of fried chicken, French fries and doughnuts examined the effects of cleaning the fryer with either an alkaline detergent or a neutral kitchen detergent on debris removal and oil life. The alkaline detergent was found to completely remove debris while the neutral detergent left significant amounts of debris. After cleaning, the fryers were operated with new oil as usual and the deterioration of this oil was monitored by assessing the color difference, AV, carbonyl value and peroxide value. These indices increased 1.3 to 2.0 times faster in the case that the neutral kitchen detergent was used, suggesting that cleaning fryer tanks with an alkaline detergent could contribute to extending the lifetime of frying oil, reducing food losses and thus achieving sustainable development goals.

Controlling the morphology of molecular assemblies formed by surfactants by photoirradiation enables the controlled release of incorporated substances, which can be applied to delivery systems for drugs and active ingredients. On the other hand, conventional photoresponsive surfactants and molecular assemblies have a slow response speed, making it difficult to control their functions at the desired time. In this review, I discuss our recent progress in the accelerated control of functions of photoresponsive molecular assemblies by using lophine dimer as a photochromic compound. The lophine dimer derivative dissociates into a pair of lophyl radicals that upon ultraviolet (UV) light irradiation, and these radical species thermally recombine although the recombination reaction is extremely slow due to the diffusion of lophyl radicals. By using the confined inner space of micelles formed by surfactants, the recombination reaction was extremely accelerated. With UV light irradiation, rapid morphological changes in micelles, formed by amphiphilic lophine dimers were observed by using in situ small-angle neutron scattering (in situ SANS) system. Moreover, the rapid controlled release of calcein as a model drug was achieved by UV light irradiation using the photoresponsive micelles. This rapid system can realize the controlled release of drugs truly at the desired time, developing an efficient and precise drug delivery system (DDS). Furthermore, it can be applied in a wide range of fields such as release control of active ingredients, efficient heat exchange control, and actuating systems.