The quality of olive oil is defined as a combination of characteristics that significantly determine its acceptance by consumers. This study was carried out to compare sensorial and chemical characteristics of sixty ‘Chétoui’ extra virgin olive oils (EVOOc) samples from six northern areas in Tunisia (Tebourba (EVOOT); Other regions (EVOON): Mornag, Sidi Amor, El Kef, Béjà and Jendouba). Trained panel taste detected ten sensory attributes. EVOOT and EVOON were defined by ‘tomato’ and ‘grass/ leave notes, respectively. Twenty one volatile compounds from EVOOc were extracted and identified by Headspace Solid-Phase Microextraction followed by Gas Chromatography- Flame Ionization Detector. Principal component and cluster analysis of all studied parameters showed that EVOOT differed from EVOON. Sensory and volatile profiles of EVOOc revealed that the perception of different aromas, in monovarietal olive oil, was the result of synergic effect of oils’ various components, whose composition was influenced by the geographical growing area.

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Sri Lanka is surrounded by the Indian Ocean, allowing plenty of fishes to be caught. Moreover, these fishes represent one of the undocumented fish resources in the world and their detailed lipid profiles have not been previously examined. In this study, the lipid content and fatty acid composition of 50 commercially important fishes from the Indian Ocean (Sri Lanka) and the Pacific Ocean (Japan) were compared. The total lipid content and fatty acid composition, including eicosapentaenoic acid (C20:5n-3, EPA) and docosahexaenoic acid (C22:6n-3, DHA), differed significantly among species. Fish from the Pacific Ocean had higher proportions of fatty acids, including EPA and DHA. Herrings and mackerels from both oceanic areas demonstrated high levels of EPA and DHA, and n-3/n-6 ratio. Brackish and freshwater fishes from both groups showed low levels of PUFAs. Fish from the Indian Ocean were high in n-6 fatty acids. Monounsaturated fatty acid levels were high in omnivorous fish from the Pacific Ocean, and saturated fatty acid levels were high in fish from the Indian Ocean. The results of this study will be of value in determining the dietary usefulness of fish caught in Sri Lanka.

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A collaborative study was conducted to evaluate an indirect enzymatic method for the analysis of fatty acid esters of 3-monochloro-1,2-propanediol (3-MCPD), 2-monochloro-1,3-propanediol (2-MCPD), and glycidol (Gly) in edible oils and fats. The method is characterized by the use of Candida rugosa lipase, which hydrolyzes the esters at room temperature in 30 min. Hydrolysis and bromination steps convert esters of 3-MCPD, 2-MCPD, and glycidol to free 3-MCPD, 2-MCPD, and 3-monobromo-1,2-propanediol, respectively, which are then derivatized with phenylboronic acid, and analyzed by gas chromatography-mass spectrometry. In a collaborative study involving 13 laboratories, liquid palm, solid palm, rapeseed, and rice bran oils spiked with 0.5–4.4 mg/kg of esters of 3-MCPD, 2-MCPD, and Gly were analyzed in duplicate. The repeatability (RSD_r) were < 5% for five liquid oil samples and 8% for a solid oil sample. The reproducibility (RSD_R) ranged from 5% to 18% for all oil samples. These RSD_R values were considered satisfactory because the Horwitz ratios were ≤ 1.3% for all three analytes in all oil samples. This method is applicable to the quantification of 3-MCPD, 2-MCPD, and Gly esters in edible oils.

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Alkyl (oligo)glucosides (AOG) are known to be environmentally compatible amphiphiles whose commercial applicability should be broadened. The present paper describes the preparation of molecular assemblies of industrially produced AOG, which is a mixture composed of different length of alkyl chains (C9-C12) with oligoglucoside moiety with a few (1–3) of glucose units. It was also described that regulation of the dispersibility of the molecular assemblies prepared by diol-boron complexation between the sugar moiety on AOG and boric acid in a dispersion medium. The molecular assembly of AOG was successfully formed by mixing AOG and cholesterols (CH). When using a suitable amount of CH (20–40 mol% with respect to AOG), the molecular assembly formed a vesicle structure. The dispersion ability of the resulting vesicle was dependent on both the boric acid concentration and pH of the dispersion medium. The light-scattering and ζ-potential measurements revealed that high concentrations (≥10 mM) of boric acid improved dispersibility the vesicles. In contrast, the vesicle agglomerated at low concentrations of boric acid (1–7.5 mM). In the absence of boric acid in dispersion medium, the vesicles were completely agglomerated. The optimum pH range for vesicle dispersion was found to be from neutral to basic (7.4–10.1). The ¹¹B NMR study revealed that borate ester formation occurred between boric acid and the diol of the sugar moiety on AOG vesicle. The present data suggest that borate ester formation that occurred on the surface of the vesicle provided negative charge to the vesicles, contributing to their dispersion via repulsive forces.

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In this work, novel hybrid-type corynomycolic acids [hybrid-OH and hybrid-COOH, with semifluoroalkyl groups (Rf-(CH₂)_n-: Rf = C₄F₉, n = 6 and Rf = C₆F₁₃, n = 3) located on the carbon atoms attached to the hydroxyl and carboxylic acid groups (C-OH and C-COOH), respectively] were successfully synthesized. The behaviors and formation of hybrid corynomycolic acid monolayers at the air-water interface were investigated by surface tension and surface pressure-area (π-A) measurements to clarify the effects of the Rf chain length, position of the semifluoroalkyl group, and surfactant molecule stereochemistry. Compared to dialkyl corynomycolic acid, both the critical micelle concentration (CMC) and the surface tension at the CMC (γ_CMC) of hybrid corynomycolic acids were reduced by the presence of the Rf group. With respect to the surface tension versus log concentration (γ vs. log C) isotherms, all syn-isomers of the hybrid-OH and hybrid-COOH acids showed two break points, while the anti-isomers showed only one break point. These different isotherms can be explained in terms of the steric repulsion between the two hydrophilic groups (OH and COO^–), which depend on the stereochemistry of the surfactant. No effect of the location of the semifluoroalkyl group was observed. With respect to the formation of a monolayer film, four parameters—the lift-off area (A_L), zero-pressure molecular area (A₀), maximum of the Gibbs elastic modulus [E_G (max)], and monolayer collapse pressure (π_c)—were measured. Both A_L and A₀ of all hybrid corynomycolic acids were larger than the corresponding dialkyl acids due to the bulky and rigid Rf groups. Interestingly, syn- and anti-hybrids had almost identical isotherms on compression, although the values of π_c of anti-hybrids were higher than those of syn-isomers. In addition, the values of E_G (max) of hybrid-COOHs were slightly larger than those of the corresponding hybrid-OHs. Using the nascent soap method (agent-in-oil method), we found that anti-F4C6-OH (a hybrid corynomycolic acid) is a promising emulsifier for a ternary system comprising octane, water, and perfluoropolyether oil.

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Recent studies have shown that EPA enriched PLs have beneficial effects on lipid metabolism. Our previous study has demonstrated that the anti-obesity and hypolipidemic effects of EPA-PL were superior to DHA-PL. In the present study, we comparatively evaluated the effects of EPA-enriched phosphatidylcholine (EPA-PC) and EPA-enriched phosphatidylserine (EPA-PS) on lipid metabolism in mice. Both 2% dietary EPA-PC and EPA-PS significantly improved serum and hepatic lipid levels in mice. The HDL-c level in mice on EPA-PC diet was significantly higher than the other two groups. The level of DHA in hepatic TG and PL were significantly increased in both EPA-PC and EPA-PS fed groups (98.3 and 117.8%, respectively; p < 0.05). Notably, the proportion of DHA in EPA-PS group was significantly higher than the EPA-PC group. EPA-PC and EPA-PS suppressed hepatic SREBP-1c mediated lipogenesis and activated PPARα mediated fatty acid β-oxidation in the liver. These data are the first to indicate that EPA-PS has beneficial effects on lipid metabolism.

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A randomized, double-blind controlled, parallel-group designed trial was performed to investigate the effect of alpha linolenic acid (ALA)-enriched diacylglycerol (DAG) on visceral fat area (VFA) in obese subjects. One hundred eighty-four obese subjects were recruited and randomly allocated to two groups consuming either 2.5 g/d control triacylglycerol (TAG) or ALA-DAG for 12 wk. A 4-wk observation period followed the 12-wk consumption period. One hundred seventy-seven subjects (N=89 in the TAG group, N=88 in the ALA-DAG group) completed the study. The change in VFA at 12-wk from baseline, as the primary outcome, was significantly lower in the ALA-DAG group than in the TAG group. The reduction in VFA was significantly correlated with the baseline VFA. Body weight and waist circumference, as the secondary measures, were also significantly lower in the ALA-DAG group than in the TAG group. The reduction in the VFA was significantly correlated with body weight reduction, suggesting that the VFA reduction was a contributing factor preventing weight gain. Safety parameters and the incidence of adverse events did not differ significantly between groups. In conclusion, ALA-DAG could be useful for reducing VFA and concomitantly suppressing weight gain with no side effects.

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Chlorella (Parachlorella beijerinckii) powder is reported to show a preventive effect against metabolic syndromes such as arteriosclerosis, hyperlipidemia, and hypertension. Approximately 60% of the chlorella content is protein. In order to understand the role of chlorella protein, we prepared a chlorella protein hydrolysate (CPH) by protease treatment. Male C57BL/6 mice were divided into three groups: a normal diet group, high-fat diet (HFD) group, and high-fat diet supplemented with CPH (HFD+CPH) group. The CPH administration improved glucose intolerance, insulin sensitivity, and adipose tissue hypertrophy in the high-fat diet-fed mice. In addition, the HFD+CPH group had significantly decreased liver total cholesterol and triglyceride levels compared with those in the HFD group. Furthermore, the HFD+CPH group had a decreased level of monocyte chemotactic protein-1 (MCP-1) in serum and a lower MCP-1 mRNA expression level in adipose tissue compared with the HFD group. The present study suggests that chlorella protein hydrolysate can prevent a high-fat diet-induced glucose disorder and fatty liver by inhibiting adipocyte hypertrophy and reducing the MCP-1 protein and gene expression.

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The fungal strain B47-9, isolated from barley, was previously selected as an effective degrader of various biodegradable plastic (BP) films such as poly(butylene succinate-co-adipate) (PBSA) and poly(butylene succinate) (PBS). The strain has not been identified based on mycological methods because it does not form fruiting bodies, which are the key to morphological identification. Here, we performed molecular phylogenetic analyses of the nuclear ribosomal RNA gene regions and their internal transcribed spacer region of B47-9 and related fungi. The results suggest that B47-9 is closely related to the genus Paraphoma. Investigation of the abilities of six strains belonging to the genus Paraphoma to degrade BPs indicated that all strains could degrade PBSA and PBS films to varying degrees. Based on our approach, we conclude that strain B47-9 is a species belonging to the genus Paraphoma.

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