Journal of oleo science最新文献

The reduction of brain-derived neurotrophic factor (BDNF) is associated with Alzheimer's disease and depression. Senescence-accelerated mouse prone 10 (SAMP10), a rapid aging animal model, exhibits age-related cognitive deficits and depression-like behavior; however, it is unclear the variation of serum BDNF levels. Here, we showed that serum BDNF levels in SAMP10 were lower than those in the normal aging characteristics mouse SAM-resistant 1 (SAMR1), and Hochuekkito suppressed the decline of serum BDNF levels in SAMP10. These results suggest that SAMP10 may be used as an animal model in decreasing serum BDNF levels and Hochuekkito could prevent the age-related BDNF decline.

The root of Rehmannia glutinosa is an ingredient in herbal medicine used for tonifying blood in Japanese Kampo medicine and traditional Chinese medicine. Biological investigations of the roots have been well reported; however, those of the leaves are limited. In this study, we examined the potential value of R. glutinosa leaves, focusing on their antioxidant activity and inhibition of advanced glycation end product formation. The leaf extract exhibited both antioxidant and anti-glycation activities in all assay systems, and the potencies of the leaves were stronger than those of the roots. The bioassay-guided fractionation led to the isolation of eight compounds from the ethyl acetate fraction. Among them and their related compounds, acteoside (3), luteolin (6), and echinacoside (12) exhibited DPPH radical scavenging, copper ion reduction, and SOD-like activities. Furthermore, compound 6, apigenin (7), and chrysoeriol (8) exhibited anti-glycation activities. The leaf extract tended to contain higher amounts of most analytes, especially compounds 3, 6, and 7, suggesting that these compounds contributed to the antioxidant or anti-glycation activities of R. glutinosa leaves. These findings will aid in the effective use of R. glutinosa leaves.

We examined the effects of dietary supplementation with 5% maltobionic acid (MA), an indigestible disaccharide, on hepatic lipid metabolism in rats fed a high-fat diet for 30 days. Supplementation with MA lowered hepatic and serum triacylglycerol (TAG) levels and homeostasis model assessment for insulin resistance and elevated serum gastric hormone glucagon-like peptide-1 (GLP-1) level. MA supplementation remarkably decreased the hepatic expression of fatty acid synthesis-related genes/proteins and slightly increased the hepatic expression of β-oxidation-related genes. These results suggest that MA reduces hepatic TAG levels, probably via the suppression of fatty acid synthesis, accompanied by decreased hyperinsulinemia and increased GLP-1.

Recent studies have revealed that the biological activity of astaxanthin differs among E/Z-isomers. Therefore, it is essential to investigate the distribution of astaxanthin isomers in the body to comprehensively elucidate their role. However, owing to the technical complexity of astaxanthin isomer analysis, detailed information regarding the precise distribution of isomers in the body remains limited. In this study, food-grade astaxanthin esters derived from Haematococcus lacustris (total Z-isomer ratio of astaxanthin = 34.5%) were administered to male Sprague-Dawley rats, and their plasma response and tissue distribution were investigated. Astaxanthin isomers were analyzed using normal-phase high-performance liquid chromatography, which can accurately measure the isomers. The maximum plasma concentration (C_max) and area under the curve from time 0 to 24 h (AUC_{0-24 h}) values of total astaxanthin isomers were determined to be 20.4 ± 4.6 ng/mL (T_max: 8.3 ± 2.3 h) and 261.8 ± 16.4 ng·h/mL, respectively. The total Z-isomer ratio of astaxanthin in the plasma increased over time and reached approximately 55% at 24 h post-administration. Astaxanthin accumulated in the liver, kidneys, lungs, and testes exhibited a high total Z-isomer ratio (> 44.0%). In plasma and tissues, the predominant astaxanthin Z-isomer was the 13Z-isomer, and minor quantities of 9Z-, 15Z-, and two unidentified astaxanthin Z-isomers (potentially multi-Z-isomers) were observed. The composition of astaxanthin isomers in the plasma and tissues differed substantially from that of the diet. These findings suggest that astaxanthin Z-isomers, particularly the 13Z-isomer, possess higher absorbability than the all-E-isomer, or that a mechanism regulates astaxanthin isomer composition in the rat body.

The oxidative stability of polyunsaturated fatty acid (PUFA) generally decreases with increasing unsaturation, however, the opposite results have been reported for aqueous emulsions prepared from PUFA. One study showed that among PUFA (fish oil) emulsions with varying μm-sized particles, the smaller emulsions had better oxidation stability. Thus, particle size may be involved in the mechanism behind the improved oxidative stability of PUFA by emulsification, and PUFA emulsions with even smaller particle sizes (i.e., nm-sized) may exhibit higher stability. To evaluate these hypotheses, once optimizing conditions under which emulsions with different sizes (100-250 nm) can be prepared using docosahexaenoic acid (DHA)-rich algal oil (DAO), these emulsions were subjected to thermal oxidation (40°C, 5 days under light shielding). Based on peroxide value (POV) data, it is apparent that even DHA, which is particularly prone to oxidation, becomes less susceptible to thermal oxidation when emulsified, and that smaller emulsions lead to greater oxidative stability. The high oxidation stability in the smallest emulsion remained high after removal of the antioxidants (tocopherols) from this emulsion. Considering these results together with preliminary data on triacylglycerol (TG) mono-hydroperoxides measured by high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS), the physical properties of the emulsion might account for the greater oxidative stability in smaller emulsions, probably due to the rapid termination of the oxidation reaction within the smaller particle in a more substrate-dense environment, rather than to the action of antioxidant tocopherols. Further research will hopefully lead to a solution to the longstanding problem of oxidation of PUFA such as DHA, which has a variety of benefits.

Carotenoids are one of the common food ingredients with potential anti-inflammatory effects. Screening of carotenoids for their anti-inflammatory effects has predominantly been conducted using macrophages, whereas comparative analyses of their effects on excessive activation of microglia remain limited. This study aimed to evaluate the anti-inflammatory effects of eight different carotenoids in lipopolysaccharide (LPS)-stimulated microglia, focusing on nitric oxide (NO) production suppression and underlying molecular mechanisms. Mouse microglia cell line MG6 was pretreated with carotenoids, followed by stimulation with LPS. Among the tested carotenoids, β-carotene, echinenone, and siphonaxanthin exhibited strong NO-inhibitory effects. Western blot analysis indicated that the effect of siphonaxanthin was mediated by NF-κB inhibition. Lipidomic analysis revealed distinct effects of β-carotene and siphonaxanthin on LPS-stimulated microglia, indicating possible differences in their inhibitory mechanisms. Gene expression analysis showed that β-carotene increased the expression of elongation of very long chain fatty acids (ELOVL) 3, ELOVL4, and fatty acid synthase, while restoring ELOVL6 mRNA expression. These results were consistent with the lipidomic analysis. Pharmacological inhibition studies demonstrated that β-carotene exerted its inhibitory effects via retinoic acid receptor (RAR)-dependent mechanisms, although the involvement of RAR-independent pathways cannot be excluded. Echinenone exhibited RAR-dependent suppression of NO production comparable to that of β-carotene. These findings suggest that carotenoids modulate neuroinflammation through multiple mechanisms, including NF-κB inhibition (e.g. siphonaxanthin), RAR activation (e.g. β-carotene and echinenone), and possibly alternative signaling pathways (e.g. astaxanthin), although the detailed mechanisms remain to be elucidated. Since RAR activation has been shown to improve cognitive function in mouse models of Alzheimer's disease, β-carotene and echinenone may have therapeutic potential in reducing neuroinflammation and preserving cognitive function. Further in vivo studies are necessary to validate these effects.

1,3-dilinoleoyl-2-palmitoylglycerol (LPL) is an important structural lipid in breast milk fat, which plays an important role in the health of infants, and therefore the development of an efficient method for the preparation of such compounds is necessary. In the present study, LPL was efficiently catalytically synthesized by immobilized lipase ANL-MARE as a biocatalyst using tripalmitate and linoleic acid in a solvent-free system, and its digestive properties were investigated. The optimal process conditions for the enzymatic acidolysis of LPL were optimized by response surface test: the molar ratio of PPP:LA was 1:10, the enzyme addition was 13.60%, the reaction temperature was 50℃, and the reaction time was 5 h. At this time, the relative content of LPL in the product was 67.78%, of which the relative content of sn-2 palmitic acid (sn-2 PA) accounted for 71.50%. In vitro gastrointestinal digestion of LPL resulted in the release of 59.69% of its fatty acids. The digested product contained higher levels of free unsaturated fatty acids and palmitic acid monoacylglycerols. In conclusion, the immobilized enzyme ANL-MARE has great potential to catalyze the preparation of LPL, which provides a new strategy and theoretical basis for the efficient preparation of human milk fat substitutes.

We examine the effect of surfactants on spray characteristics of mist aerosol containing oil-in-water (O/W) emulsions to evaluate the mechanism on the splitting of liquid film sprayed from mist aerosol containing O/W emulsions as mist aerosol formulation. We proposed that the splitting of liquid film sprayed from mist aerosol containing O/W emulsions as mist aerosol formulation was attributed to the adsorption of oil droplets to air/water interface in liquid film sprayed from mist aerosol. The splitting of liquid film sprayed from mist aerosol containing O/W emulsions differed with type of surfactants. This indicates that the adsorption of oil droplets to air/water interface in liquid film sprayed from mist aerosol is controlled by surfactants. We also found that the prompt adsorption of surfactant molecules themselves to air/water interface enhanced the splitting of liquid film sprayed from mist aerosol. Namely, the prompt adsorption of oil droplets and surfactants to air/water interface in liquid film leads to the earlier splitting of liquid film, and the resulting larger angle and area of mist sprayed from mist aerosol containing O/W emulsions.

This study provides a comprehensive investigation of the phytochemical composition, antioxidant capacity, and enzyme inhibition properties of Equisetum ramosissimum, a medicinal plant traditionally used in Turkey. The main aim was to characterize its bioactive compounds and evaluate their biological relevance using modern analytical techniques. Ethanolic extracts of the plant were analyzed by LC-MS/MS, enabling the identification and quantification of 13 phenolic compounds, including kaempferol (1458.11 µg/L), vanillic acid (1002.26 µg/L), and resveratrol (424.12 µg/L). Antioxidant activity was assessed through DPPH, ABTS, FRAP, and CUPRAC assays, where the extract demonstrated strong radical scavenging and metal reducing capacity. Enzyme inhibition studies revealed significant inhibitory effects on AChE, BChE, and α-glucosidase, with IC₅₀ values comparable to standard inhibitors. These findings indicate that E. ramosissimum is a rich source of phenolic compounds with strong antioxidants and enzyme inhibitory properties. The originality of this work lies in its systematic evaluation of Turkish E. ramosissimum populations, highlighting their potential as natural therapeutic agents for managing oxidative stress-related diseases, neurodegenerative disorders, and diabetes.