Thai Tea Seed Oil and Virgin Olive Oil Similarly Reduce Plasma Lipids: A Pilot Study within a Healthy Adult Male Population

The potential cardiovascular benefit of virgin olive oil (VOO) is widely recognized. However, the use of VOO at very high cooking temperatures makes these oils poorly suited for many Asian dishes. The use of tea seed oil (TSO) is increasing in Thailand, with TSO having a higher smoke point than VOO. The current study examines the effects of daily TSO intake in healthy adults. In a randomized, single-blind crossover design, 12 men consumed for 3 weeks 40 g day⁻¹ of food prepared with either TSO or VOO as a cooking oil. Plasma lipids, thiobarbituric acid reactive substances (TBARS), and oxidant defense enzyme activities are measured before and after each 3-week intervention period. Gas chromatography analysis of TSO and VOO demonstrates that both oils are equally high in monounsaturated fatty acid. The dietary incorporation of TSO and VOO for three weeks reduces low-density lipoprotein cholesterol (LDL-C) concentrations by 15% and 13%, respectively; with total cholesterol (TC) levels lowered by 10% in both groups. No significant changes in TBARS or antioxidant enzyme activity is observed. These results support the concept that Thai TSO can be utilized as a suitable and healthy alternative oil for high-temperature cooking in many Thai and Asian diets. Practical Applications: Tea seed oil from Camellia oleifera grown in Thailand has been recently reported to favorably lower lipid profiles in hamsters fed a high-fat diet in a manner similar to feeding refined olive oil or grapeseed oil. A pilot crossover trial is conducted to compare the effects of three weeks of daily intake of either TSO or VOO in healthy human adults. Consumption of both oils produced significant reductions in TC and LDL-C. Thai TSO leads to favorable lipid profiles and is a reasonable choice for many Thai and Asian food recipes.     

生物法提取纯天然茶籽油联产茶皂素工艺研究

探讨了生物法提取纯天然茶籽油联产茶皂素的工艺,选择碱性蛋白酶对油茶籽仁进行酶解,经三相离心,茶籽油的提取率高达95％。所得产品属于纯天然高级健康食用植物油,各项指标均符合国家标准。通过膜分离技术可得到具有高生物活性的天然茶皂素,且纯度高达90%。     

Virgin Grape Seed Oil Alleviates Insulin Resistance and Energy Metabolism Disorder in Mice Fed a High‐Fat Diet

This study aims to investigate the potential of virgin grape seed oil (VGSO) to improve insulin resistance and energy metabolism disorder in mice fed a high‐fat diet. The results show that respiratory exchange rate and energy consumption in mice can be increased by the administration of VGSO. Insulin resistance is significantly alleviated by VGSO, which can be attributed to its protective effect on hexokinase and α‐glucosidase activities and improvement in leptin resistance. The effect of refined grape seed oil (RGSO), RGSO reinforced with polyphenol, RGSO reinforced with unsaponifiables, and RGSO reinforced with polyphenol and unsaponifiables on oral glucose tolerance, homeostasis model assessment of insulin resistance and quantitative insulin sensitivity check index are determined and compared. The results suggest that polyphenol may be the most critical factor for regulating insulin resistance. Specific linear and polynomial equations are provided to explain the correlation between insulin resistance, energy metabolism, and hyperlipidemia. Practical Applications: The effects of virgin grape seed oil (VGSO) on insulin resistance and energy metabolism disorder in mice fed a high‐fat diet were investigated. In addition, the key component in VGSO for regulating insulin resistance was preliminarily investigated. Furthermore, the correlations among fasting blood glucose, triglyceride/cholesterol concentration, and respiratory exchange rate/energy consumption/activity level were investigated. This research will provide a theoretical basis for the development of functional edible oil for high blood lipid, cholesterol, and diabetes patients.     

Efficient and Response Surface Optimized Aqueous Enzymatic Extraction of Camellia oleifera (Tea Seed) Oil Facilitated by Concurrent Calcium Chloride Addition

This paper reports an efficient aqueous enzymatic extraction (AEE) method for Camellia oleifera seed oil with the aid of response surface analysis. A maximum oil recovery of ~93.5% was obtained when a 2‐step AEE process was performed using 0.80% cellulase (v/w) solution at pH 6.0 maintained at 50 °C for 1 h followed by a solution of 0.70% Alcalase® with pH 9.2 at 57 °C for 4.1 h. It was found that the addition of Ca²⁺ during the proteolysis stage improved the free oil yield from ~62.1 to ~86.6%. This was attributed to the removal of tea saponins, cross‐linkage of anionic polysaccharides, and destabilization of cream emulsion by Ca²⁺. This was verified by decreased tea saponin and polysaccharide levels in the cream emulsion and bulk solution as well as lowering of the emulsion fraction. It was determined that addition of CaCl₂ solution in continuous flow to the proteolysate is superior to one‐time or batch addition in inhibiting emulsion formation. The addition of CaCl₂ may provide a means of replacing the more laborious, time‐consuming demulsification process otherwise required.     

Fatty Acid Composition and Antioxidant Activity of Tea (Camellia sinensis L.) Seed Oil Extracted by Optimized Supercritical Carbon Dioxide

Seeds are another product in addition to leaves (raw materials for teas) of tea (Camellia sinensis L.) plant. The great increase of tea consumption in recent years raises the challenge of finding commercial applications for tea seeds. In the present study, supercritical carbon dioxide (SC-CO(2)) extraction edible oil from tea seed was carried out, response surface methodology (RSM) was used to optimize processing parameters including time (20-90 min), temperature (35-45 °C) and pressure (50-90 MPa). The fatty acid composition and antioxidant activity of the extracted oil was also investigated. The highest yield of oil (29.2 ± 0.6%) was obtained under optimal SC-CO(2) extraction conditions (45 °C, 89.7 min and 32 MPa, respectively), which was significantly higher (p < 0.05) than that (25.3 ± 1.0%) given by Soxhlet extraction. Meanwhile, tea seed oil extracted by SC-CO(2) contained approximately 80% unsaturated fatty acids and showed a much stronger scavenging ability on the DPPH radical than that extracted by Soxhlet. SC-CO(2) is a promising alternative for efficient extraction of edible oil from tea seed. Moreover, tea seed oil extracted by SC-CO(2) is highly edible and has good antioxidant activity, and therefore may play a potential role as a health-promoting food resource in human diets.     

Black Raspberry Seed Oil Improves Lipid Metabolism by Inhibiting Lipogenesis and Promoting Fatty‐Acid Oxidation in High‐Fat Diet‐Induced Obese Mice and db/db Mice

The objective of this study was to evaluate the beneficial effect of α‐linolenic acid‐rich black raspberry seed (BRS) oil on lipid metabolism in high‐fat diet (HFD)‐induced obese and db/db mice. Five‐week‐old C57BL/6 mice were fed diets consisting of 50% calories from lard, 5% from soybean, and 5% from corn oil (HFD), or 50% calories from lard and 10% from BRS oil (HFD + BRS oil diet) for 12 weeks. Six‐week‐old C57BL/KsJ‐db/db mice were fed diets consisting of 16% calories from soybean oil (standard diet), 8% from soybean, and 8% from BRS oil, or 16% from BRS oil for 10 weeks. The BRS oil diets lowered the levels of triacylglycerol, nonesterified fatty acids, and total cholesterol in serum and liver of both of the obese and db/db mice as compared with the HFD and standard diet, respectively. mRNA levels of lipogenesis markers including cluster of differentiation 36, fatty‐acid‐binding protein 1, sterol regulatory element binding protein 1c, fatty‐acid synthase, and solute carrier family 25 member 1 in the liver of the BRS oil groups were lower than those in the liver of the HFD and standard groups in the obese and db/db mice, respectively. On the other hand, fatty‐acid oxidation markers including carnitine palmitoyltransferase 1A, acyl‐CoA dehydrogenase, hydroxylacyl‐CoA dehydrogenase α, and acyl‐CoA oxidase in the liver of the BRS oil groups were higher than those in the liver of the HFD and standard groups in the obese and db/db mice, respectively. Peroxisome proliferator‐activated receptor α mRNA and protein levels increased in the liver and epididymal adipose tissue of the obese and db/db mice fed BRS oil compared with HFD and standard diet, respectively. BRS oil might improve lipid metabolism by inhibiting lipogenesis and promoting fatty‐acid oxidation in HFD‐induced obese and db/db mice.     

Quantitative Determination of Natural Glycolipids from Oil Seed by Automated High‐Performance Thin‐Layer Chromatography (HPTLC)

The role of glycolipids in vegetable oil refining and production of bio‐based fuels has not been disclosed so far. Such investigations required a reliable and reproducible quantitative determination of these compounds. Fundamental data were therefore established on the quantitative determination of glycolipids in vegetable oil gums by means of high‐performance thin‐layer chromatography (HPTLC). Concentrating on five abundant natural glycolipid classes found in these oils, identification of a suitable separation method for the employed glycolipid mixture and those parameters relevant for successful detection were considered in detail. The special importance of sample volume when employing quantitative HPTLC was discussed. Acetone/chloroform/water 6:3:0.4 (v/v/v) was identified as a convenient mobile phase for the investigated issue. A derivatization reagent comprising methanol, copper(II)sulfate pentahydrate, sulfuric acid 98 %, and phosphoric acid 85 % was identified. Subsequent heating at 135 °C for 10 min finished the derivatization and enabled detection at λ = 370 nm. Calibration curves ranging from 1500 to 31.25 ng/mL, regarding both peak area and peak height, were determined. The good correlation of parameters enabled the application of the method to real oil gum samples from sunflower and soybean oil. This revealed that digalactosyldiglycerides in combination with either sterylglucosides or acylated sterylglucosides represented the major glycolipid classes in these oils.     

The quality and volatile‐profile changes of camellia oil (Camellia oleifera Abel) following bleaching

Bleaching is a necessary step in the production of refined camellia oil (Camellia oleifera Abel) since crude oil has a dark brown color, due to pigments extracted from the seed coat during pressing, which is unacceptable to consumers. In order to understand the quality change and oxidative state of camellia oil in the bleaching step, measurements of various quality parameters, i.e. peroxide value (POV), free fatty acids (FFA), UV absorbance, and the volatile profiles of crude and bleached oils, were carried out. The results showed that FFA, K₂₇₀, and K₂₃₂ increased, whereas POV decreased, with increase of the activated earth dosage of 0–4% and of bleaching time from 0 to 40 min at 110 °C. As the amount of activated earth was increased from 0 to 4% with bleaching at 110 °C for 30 min, various classes of volatile compounds increased in concentration: aldehydes (23.7 µg/g), alcohols (13.2 µg/g), esters (8.0 µg/g), alkenes (2.0 µg/g) and ketones (1.9 µg/g). Likewise, when bleaching was carried out at 110 °C with 3% activated earth and the bleaching time varied between 0 and 40 min, the concentrations of volatile compounds also increased: aldehydes (27.7 µg/g), alcohols (18.2 µg/g), esters (7.3 µg/g), ketones (3.2 µg/g) and alkenes (0.6 µg/g). These findings indicate that hydroperoxides in the oil were decomposed into lower‐molecular‐weight products in the process of bleaching and that the extent of this decomposition can be controlled by time and amount of activated earth.     

Oxidation kinetics in olive oil triacylglycerols under accelerated shelf‐life testing (25–75 °C)

A kinetic study of the autoxidation reaction in olive oil triacylglycerols stored in darkness at different temperatures (25, 40, 50, 60 and 75 °C), in absence of pro‐ and antioxidant compounds to avoid confounding effects, is described. After the induction period (IP) the decrease in the oxidizing substrate and the formation of primary oxidation products followed a pseudo‐zero‐order kinetic, and the calculated E_a from the Arrhenius equation for the formation of hydroperoxides was 32.1 kJ·mol^?1. The formation of secondary oxidation products followed a pseudo‐first‐order kinetic whose rate reaction constant also increased exponentially with temperature. The first oxidation index to exceed the upper limit in the EU regulations was PV, followed by K₂₃₂ and K₂₇₀. The time required reaching these limits and the rancidity threshold showed a potential dependence on temperature, and therefore with accelerated storage at 75 °C, POO shelf‐life in ambient conditions (25 °C) can be predicted. Finally, there was a good linear relationship between the time required to reach the rancidity threshold and the IP of the formation of the 2,4‐decadienal, and hence this instrumental determination could be useful to measure sensory recognition of the rancid defect in POO.     

Activity‐Fed Translation (AFT) Assay: A New High‐Throughput Screening Strategy for Enzymes in Droplets

There is an increasing demand for the development of sensitive enzymatic assays compatible with droplet‐based microfluidics. Here we describe an original strategy, activity‐fed translation (AFT), based on the coupling of enzymatic activity to in vitro translation of a fluorescent protein. We show that methionine release upon the hydrolysis of phenylacetylmethionine by penicillin acylase enabled in vitro expression of green fluorescent protein. An autocatalytic setup where both proteins are expressed makes the assay highly sensitive, as fluorescence was detected in droplets containing single PAC genes. Adding a PCR step in the droplets prior to the assay increased the sensitivity further. The strategy is potentially applicable for any activity that can be coupled to the production of an amino acid, and as the microdroplet volume is small the use of costly reagents such as in vitro expression mixtures is not limiting for high‐throughput screening projects.     

Cardiac Lipid Metabolism Is Modulated by Casimiroa edulis and Crataegus pubescens Aqueous Extracts in High Fat and Fructose (HFF) Diet‐Fed Obese Rats

This study aim to evaluate the effect of Casimiroa edulis and Crataegus pubescens aqueous extracts on cardiac lipotoxicity in obese rats. Both extracts decrease cardiac hypertrophy and steatosis in high fat and fructose (HFF)‐diet‐fed obese rats. C. pubescens decreases the cardiac content of 16 and 18 carbon‐length fatty acids, whereas C. edulis extract does not alter the fatty acid profile. Regarding lipotoxic compounds, C. pubescens reduces the cardiac content of 16 and 18 carbon‐length ceramides and diacylglycerols, whereas C. edulis extract reduces ≥20 carbon‐length lipotoxic compounds. Both extracts down‐regulate fatty acid synthase (Fasn) and acetyl‐CoA carboxylase (Acaca) (lipogenesis), glyceril‐3‐phosphate acyltransferase (Gpat) (diacylglycerol synthesis) and serine palmitoyltransferase 1 (Spt1) (ceramide synthesis), and up‐regulate carnitine palmitoyltransferase 1 (Cpt1) and acyl‐CoA dehydrogenase (Acadm) (β‐oxidation), and the greatest effect is observed with C. pubescens. In addition, C. edulis exerts the greatest cardiac anti‐inflammatory activity, whereas C. pubescens shows the highest cardiac antioxidant activity. The cardioprotective effect of C. pubescens may be associated with its content of (?)‐epigallocatechin gallate, (+)‐catechin, chlorogenic acid, caffeic acid, and β‐campesterol, whereas the beneficial effect of C. edulis may be related to its high content of steroidal saponins and alkaloids. Therefore, these results demonstrate that both herbal aqueous extracts ameliorate cardiac lipotoxicity in HFF‐diet‐fed rats, and C. pubescens exerts a greater beneficial effect. Practical Applications: This study proposes the characterization of fatty acids and lipotoxic compounds (ceramides and diacylglycerols) of cardiac tissue in combination with the determination of the expression of specific genes related to lipid metabolism to identify the mechanisms associated with the cardioprotective effects of herbal extracts. The results obtained in this study demonstrate the cardioprotective potential of Casimiroa edulis and Crataegus pubescens aqueous extracts through the modulation of cardiac lipid metabolism in high fat and fructose diet fed obese rats. Therefore, these herbs can be used for the development of functional beverages or the extraction of bioactive compounds with cardioprotective effect.