Tocopherol Compounds Research Articles

Optimization of Oil and Tocopherol Extraction from Maqui (Aristotelia chilensis (Mol.) Stuntz) by Supercritical CO2 Procedure.

This study focused on the oil extraction from freeze-dried maqui (Aristotelia chilensis) by supercritical fluid extraction with carbon dioxide (SFE-CO2). The basic objective was to optimize the oil yield and the tocopherol concentration. A Box/Behnken experimental design was developed with three processing variables: supercritical pressure (74, 187, and 300 bar), temperature (35, 48, and 60 °C), and extracting time (30, 135, and 240 min). Multiple optimizations, based on the combination of factor levels at 274 bar, 240 min, and 60 °C, led to the highest oil yield and tocopherol values. The validation of the optimized conditions of maqui oil extraction led to an oil yield of 8% and values of 735, 53, and 97 (mg·kg-1 oil) for α-tocopherol, α-tocotrienol, and γ-tocopherol, respectively. A higher concentration of tocopherol compounds was observed when compared to the employment of the conventional extracting method. The optimized SFE-CO2 method led to an oil extract exhibiting higher Hydrophilic-Oxygen Radical Absorbance Capacity (H-ORAC) assay and total phenol content (22 μmol Trolox equivalents·g-1 oil and 28 mg gallic acid equivalents·g-1 oil) than the oil obtained by the conventional procedure. A practical and accurate oil extraction is proposed for obtaining tocopherol-enriched oil including high concentrations of valuable lipophilic antioxidants.

Physicochemical Properties and Bioactive Compounds of Three Varieties of Melon (Cucumis melo) Seed Oils

The physicochemical composition of the oil extracted from three different melon seed varieties (named Uzbek-Russian, Soski, and Soski Green), which were collected from three various geographical parts of Iran (north, northeast, and center), was determined in 2021 and 2022. The macronutrient components, fatty acid profile, sterol compounds, phenolic compounds, tocopherols, and oxidative stability of the melon seed oils were determined. The oil content of melon seeds ranged from 43.3% to 47.3%. Linoleic (54.48% to 60.35%), oleic (24.35% to 28.03%), and palmitic acids (10.15% to 12.65%) were the predominant fatty acids. No significant differences were observed between the three cultivars and between the 2 years of the study in terms of macronutrient components and fatty acid profiles (p > 0.05). Twelve different phenolic compounds were identified, of which caffeic acid was the major compound, ranging from 39.74% ± 1.70% (Soski Green) to 63.45% ± 1.25% (Uzbek-Russian). The amounts of caffeic acid and oxidative stability of Uzbek‐Russian were significantly higher than those in the two other cultivars. β‐Sitosterol (approximately 60%) and γ‐tocopherol (71.6 to 84.07 mg/100 g) were the major sterol and tocopherol compounds, respectively. The results indicated that the physical and chemical specifications of the three investigated melon seed oils were stable for two consecutive years. Therefore, melon seed oil is a rich source of bioactive compounds and could be introduced as a healthy oil for human consumption.

Optimisation of Low-Toxicity Solvent Employment for Total Lipid and Tocopherol Compound Extraction from Patagonian Squid By-Products.

The extraction of total lipids and tocopherol compounds from Patagonian squid (Doriteuthis gahi) by-products (viscera, heads, skin, etc.), resulting from squid mantel commercialisation, was studied. An optimisation simplex-lattice design by employing low-toxicity solvents (ethanol, acetone, and ethyl acetate) was carried out taking into account their relative concentrations. The variance analysis of data showed that the quadratic model was statistically significant (p < 0.05); empirical coded equations were obtained as a function of the low-toxicity solvent ratios. The optimised lipid extraction was obtained by employing the 0.642/0.318/0.040 (ethanol/acetone/ethyl acetate) solvent ratio, respectively, leading to an 84% recovery of the total lipids extracted by the traditional procedure. In all extracting systems tested, the presence of α-, γ-, and δ-tocopherol compounds was detected, α-tocopherol being the most abundant. For α-, γ-, and δ-tocopherol compounds, the optimisation process showed that acetone extraction led to the highest concentrations in the lipid extract obtained (2736.5, 36.8, and 2.8 mg·kg-1 lipids, respectively). Taking into account the recovery yield on a by-product basis, the values obtained for the three tocopherols were included in the 88.0-97.7%, 80.0-95.0%, and 25-75% ranges, respectively, when compared to the traditional extraction. This study provides a novel and valuable possibility for α-tocopherol extraction from marine by-products.

The potential of wild olive leaves (Olea europaea L. subsp. oleaster) addition as a functional additive in olive oil production: the effects on bioactive and nutraceutical compounds using LC-ESI-QTOF/MS.

This study aims to investigate the influence of traditional maceration upon the enrichment of olive oil with oleaster leaves. The phenolic and tocopherolic compositions of control olive oil and enriched olive oils were determined. The influence of these oil preparation procedures on oil quality indicators was also investigated through spectrophotometric indices and fatty acid profiles. The total contents of bioactive compounds and pigments improved in oils obtained by maceration of fresh wild olive leaves, and were in statistically significant correlation with leaves proportions additions. The obtained results revealed that 15 phenolic compounds belonging to different phenolic types were characterized and quantified by an effective HPLC–DAD–ESI–MS/MS method. In all expected olive oils, the oleuropein aglycon (3,4-DHPEA-EA), and ligstroside aglycon (p-HPEAEA) derivatives were the most abundant compounds. Similarly, to phenolic compounds, tocopherols strongly increased with leaves addition during maceration process.The data obtained from this study suggested that the addition of olive leaf to oils allowed more functional olive oils with higher antioxidant contents. Thus, Extra Virgin Olive Oil (EVOO) extracted with 10% of olive leaves presented the highest amount of phenolic and tocopherol compounds.

The bioactive constituents and antioxidant activities of ten selected Brazilian Cerrado fruits.

This study measured the total levels of phenolic, anthocyanin, carotenoid, and tocopherol compounds, and vitamin C in ten fruits from the Brazilian Cerrado: araçá-boi, bacaba, bacupari, biribá, cajuí, curriola, marmelada-espinho, mirindiba, murici, and puçá-preto. Five extracts were prepared from each fruit using solvents with different polarities. The Trolox equivalent antioxidant activity, oxygen radical absorbance capacity, and inhibition of β-carotene bleaching were determined for each extract. Scott-Knott test and principal component analysis showed that the analyzed fruits were rich sources of different classes of bioactive compounds, with levels comparable to those in commonly consumed fruits such as guavas, and various berries and citrus fruits. To our knowledge, this is the first comprehensive study of the bioactive compounds and antioxidant activities of biribá, cajuí, marmelada-espinho, and mirindiba. Moreover, mirindiba was found to be a rich source of vitamin C and phenolics, with an average level of carotenoids and tocopherols.

Importance and Relevance of Phytochemicals Present in Galenia africana.

Many people in developing countries rely primarily on medicinal plants as their main source of healthcare, particularly for the treatment of skin infections. Despite the widespread use of medicinal plants, there is a lack of literature describing the relevance and risks of exposure of the phytochemicals present. Galenia africana has been used traditionally in the form of pastes, decoctions, and lotions to treat wounds and other skin-related ailments. This is a report on the phytochemical composition of G. africana and a review on the pharmacological importance and relevance of these phytochemicals. The major groups of phytochemicals identified in G. africana extracts were aliphatics, aliphatic triterpenoids, fatty acids, flavonoids, and phenolic and tocopherol compounds. These have been found to exhibit medicinal properties, thus highlighting the need to assess the safety of G. africana for topical application. The information related to the safety of the various compounds could indicate the potential risks related to accidental intake of the extract upon topical product applications. This report concludes that the quantities of the phytochemicals present in G. africana should not cause undue risk to human health, which provides comfort to pursue future work on using and developing G. africana as a therapeutic agent.

Protective effect of argan oil on DNA damage in vivo and in vitro

Background: Iron-overload is a well-known cause for the development of chronic liver diseases and known to induce DNA damage. Material and methods: The protective effect of argan oil (AO) from the Argania spinosa fruit and olive oil (OO) (6% AO or OO for 28 days) was evaluated on a mouse model of iron overload (3.5mg Fe2+/liter) and in human fibroblasts where DNA damage was induced via culture under hyperoxia (40% oxygen). Results: Iron treatment induced DNA damage in liver tissue while both oils were able to decrease it. We confirmed this effect in vitro in MRC-5 fibroblasts under hyperoxia. A cell-free ABTS assay suggested that improvement of liver toxicity by both oils might depend on a high content in tocopherol, phytosterol and polyphenol compounds known for their antioxidant potential. The antioxidant effect of AO was confirmed in fibroblasts by reduced intracellular peroxide levels after hyperoxia. However, we could not find a significant decrease of genes encoding pro-inflammatory cytokines (TNFα, IL-6, IL-1β, COX-2) or senescence markers (p16 and p21) for the oils in mouse liver. Conclusion: We found a striking effect of AO by ameliorating DNA damage after iron overload in a mouse liver model and in human fibroblasts by hyperoxia adding compelling evidence to the protective mechanisms of AO and OO.

Karakteristik Mikroemulsi a-Tokoferol pada Perbandingan Campuran Tiga Surfaktan Nonionik dan Lama Pengadukan

Microemulsions have thermodynamics and stable kinetics as carriers of ?-tocopherol compounds. This study aimed to know the effect of mixtures ratio of three nonionic surfactants and stiring time on the characteristics of ?-tocopherol microemulsion, as well as to obtain the best stiring time and mixture ratio of three nonionic surfactants to produce ?-tocopherol microemulsion. This experiment used a randomized block design with two factors. The first factor is the ratio of a mixture of three nonionic surfactants with Hydrophilic-Lipophilic Balance (HLB) 14.5. The second factor is stirring time. Data were analyzed using analysis of variance and continued with BNJ test. Test the effectiveness index to determine the best treatment. The results showed that the comparison of three surfactant mixtures, stirring duration and interaction between treatments significantly affected the characteristics of ?-tocopherol microemulsion. Comparison of the mixture of three surfactants Tween 80: Span 80: Tween 20 (v / v%) HLB 14.5 consisting of F2 (89,5 : 5,5 : 5) and 4 minutes stirring time is the best treatment for the characteristics of ?-Tocopherol microemulsion. The best treatment has the characteristics of ?-tocopherol microemulsions namely transparent appearance, stable to centrifugation (4500 rpm), pH (4.5; 5.5 and 6.5) and dilution (1: 9, 1:49 and 1:99) with Turbidity index values ??are below 1 percent. Microemulsion turbidity index values ??before and after centrifugation were 0.19 percent and microemulsion turbidity at pH 4.5 and 1: 9 dilution were 0.11 percent.&#x0D; Keywords: microemulsion, stirring time, surfactan non ionic, ?-Tocoferol

The effects of honey on pro- and anti-inflammatory cytokines: A narrative review.

Honey contains flavonoids and phenolic acids, and because of their antioxidant and anti-inflammatory properties, they may play an important role in human health. The purpose of this review was to synthesize the effects of natural honey on pro- and anti-inflammatory cytokines. The effects of honey on wound healing and immunity appear to be inconsistent. The available databases )PubMed and Scopus) were searched and 42 studies were assessed. In patients with cancer, honey has been reported to inhibit the effects of pro-inflammatory factors such as TNF-α and IL-6. In patients with neuro-inflammatory disorders honey has been shown to inhibit the expression of pro-inflammatory markers. It has also been reported that honey can reduce TNF-α expression in conditions associated with liver injury, by suppressing TNF-α converting enzyme activity. Honey inhibits APAP-induced hepatocellular necrosis by modulating the expression of IL-10 and IL-1ß. Animal studies have shown that honey can reduce serum IL-1ß, IL-6 and TNF-α concentration and increase IL-10 concentrations in a model of gastric ulcer. Some studies in diabetics have shown that honey can reduce serum TNF-α, IL-6, IL-1ß and TGF-ß by inhibiting NF-Kß. The source and type of honey and its component have not been indicated in various clinical and practical studies, which are a limitation of these studies, in relation to reproducing them. Sigma, Manuka, Gelam and Tulang honey have been used in most of the in vitro and animal studies. The animal studies have demonstrated similar effects on pro-inflammatory factors, which include reducing serum TNF-α, IL-6 and IL-1β as well as increasing IL-10. There are few human RCTs investigating the effects of honey on inflammatory cytokines. Only one RCT has reported the type of honey that they have used. Tulang honey has been reported to increase serum TNF-α and decrease hs-CRP, which is therefore controversial. Further high-quality studies are needed to firmly establish the clinical efficacy of honey. Because most studies had used different duration, type of honey and dosage, which make them difficult to contextualize, as the phytochemical content of a honey may depend on its source. Furthermore, it is unclear whether honey's anti-inflammatory effects are related to its phenolic or tocopherol compounds, and whether its effects are greater than these individual components.

Variability for oil, protein, lignan, tocopherol, and fatty acid concentrations in eight sesame (Sesamum indicum L.) genotypes

Sesame (Sesamum indicum L.) is an important oil seed with edible and potentially nutritional and medical uses in most countries and may show variability for bioactive concentrations. The objective of this study was to evaluate seed production weights, numbers, oil, protein, lignan, tocopherol, and fatty acid concentrations in seeds from 8 randomly diverse sesame genotypes with various seed coat colors over two years. Oil analysis were conducted using NMR (nuclear magnetic resonance) on a Bruker mq-one minispec. Protein was measured by combustion on an Elementar Rapid N Exceed nitrogen analyzer. Lignan and tocopherol compounds were prepared and analyzed by HPLC (high performance liquid chromatography) on an Agilent 1100. Fatty acids were separated by gas chromatography on an Agilent 7890A with a 15 m DB23 analytical column and FID (flame ionization detector). The bioactives and 1000 seed weights were significantly influenced by genotype, except for heptadecenoic acid (17:1), while total seed weight, total seed numbers, sesamolin, γ-tocopherol, and oleic acid (18:1) were influenced by year. Oil, protein, δ-tocopherol, and margaric acid (17:0) showed a year x genotype interaction. Significant 1000 seed weights ranged from 1.8 to 3.3 g while oil and protein concentrations significantly ranged from 29.43–54.69% and 13.92–21.76%, respectively. Sesamin and sesamolin ranged significantly from 0.55 to 8.98 mg/g and tocopherols ranged from 0 to 239.58 μg/g. The major unsaturated fatty acids, oleic (18:1) and linoleic (18:2) acids significantly ranged from 26.60 to 54.85 % while the minor unsaturated fatty acids ranged from 0.13 to 0.89 %. The saturated fatty acids significantly ranged from 0 to 10.58 %. Several correlations were observed among the bioactives. The 8 sesame genotypes can be used in breeding programs to develop new cultivars with enhanced bioactives.

Physical stability of microliposomes in bene (Pistacia atlantica) oil with different formulations

Bene oil (pistacia atlantica), as a plant source, is rich in phenolic and tocopherol compounds and has significant antioxidant, therapeutic and antimicrobial effects. Encapsulation of hydrophobic compounds in liposome system is an ideal solution for protecting them against destruction during storage. An important advantage of liposomes is the encapsulation of hydrophilic, hydrophobic and amphiphilic compounds by using natural phospholipids, such as lecithin, with beneficial effects. The aim of this study is to encapsulate the bene kernel oil in the form of microliposomes. For this purpose, the effect of composition of liposomes based on lecithin and cholesterol was studied using the Mozafari method. Liposomes are prepared using lecithin and cholesterol in the ratios of 60:0, 50:10, 40:20 and 30:30. Particle size, size distribution, zeta potential and encapsulation efficiency were charac-terised. According to the result, the size of liposomes was dependent on their composition, but the wasaffected significantly affected by adding cholesterol (P &lt; 0.05). Average diameter of the particles was between 4 and 9 µm. Liposome with a ratio of 40:20 had the smallest size. By applying cholesterol, zeta potential increased from 16.4 mV to 32.39 mV, which indicates electrostatic stability of liposomes. In general, with encapsulation efficiency of 84.33%, the ratio of 40:20 is considered as an ideal concentration in the formulation of microliposomes. Based on the results, bene oil-loaded liposomes with a lecithin:cholesterol formulation ratio of :as 40:20 was chosen as an optimal formulation because of its smaller particle size, higher zeta potential and suitable stability, which can be used in trapping, delivering and releasing hydrophilic, adipose-friendly and amphiphilic compounds (dual-friendly).

Physical stability of microliposomes in bene (Pistacia atlantica) oil with different formulations

Bene oil (pistacia atlantica), as a plant source, is rich in phenolic and tocopherol compounds and has significant antioxidant, therapeutic and antimicrobial effects. Encapsulation of hydrophobic compounds in liposome system is an ideal solution for protecting them against destruction during storage. An important advantage of liposomes is the encapsulation of hydrophilic, hydrophobic and amphiphilic compounds by using natural phospholipids, such as lecithin, with beneficial effects. The aim of this study is to encapsulate the bene kernel oil in the form of microliposomes. For this purpose, the effect of composition of liposomes based on lecithin and cholesterol was studied using the Mozafari method. Liposomes are prepared using lecithin and cholesterol in the ratios of 60:0, 50:10, 40:20 and 30:30. Particle size, size distribution, zeta potential and encapsulation efficiency were characterised. According to the result, the size of liposomes was dependent on their composition, but the wasaffected significantly affected by adding cholesterol (P &lt; 0.05). Average diameter of the particles was between 4 and 9 µm. Liposome with a ratio of 40:20 had the smallest size. By applying cholesterol, zeta potential increased from 16.4 mV to 32.39 mV, which indicates electrostatic stability of liposomes. In general, with encapsulation efficiency of 84.33%, the ratio of 40:20 is considered as an ideal concentration in the formulation of microliposomes. Based on the results, bene oil-loaded liposomes with a lecithin: cholesterol formulation ratio of :as 40:20 was chosen as an optimal formulation because of its smaller particle size, higher zeta potential and suitable stability, which can be used in trapping, delivering and releasing hydrophilic, adipose-friendly and amphiphilic compounds (dual-friendly).

INVESTIGATING THE ANTIOXIDANT PROPERTIES OF IRANIAN CHILI PEPPER EXTRACT

Stress oxidative factors are known to causes diseases resulting from metabolic disorders. Therefore, preventing, or at least decreasing the amount of these factors may have a positive impact on prevention or improvement of the metabolic problems. Recently, the herbal medicines are more considered due to more effectiveness. The application of synthetic antioxidants has been reduced recently due to their adverse effects on human health. The present research aims at evaluating the antioxidant power of chili pepper. Some solvents such as water, ethanol and water-ethanol solution, with or without ultrasound wave application, are used to provide the chili pepper extracts. The amount of tocopherol and phenol compounds in the extracts has been measured using stoichiometry method and the antioxidant power of the extracts was measured and analyzed by beta-carotene and DPPH tests. Finally, the extracts’ oxidative stability was determined. The data was statically analyzed by Analysis of Variance (ANOVA) and Duncan Multiple Range Test. The P level of &lt;0.05 was considered statistically significant. The results showed that the amount of phenol compounds in terms of Gallic acid in different extracts are between 1066.3 and 1172.27 mg/kg, and the amount of tocopherol compounds in terms of alpha-tocopherol is between 693.52 and 867.65 mg/ml. the oxidative stability index in different extracts was between 5.55 and 7.23 hours. The inhibitory percentage of Linoleic acid oxidation in the extract varied between 57.2 and 83.6%, and the inhibitory percentage of DPPH radicals in different extracts varied between 71.33 and 91.87%. The maximum and minimum efficiency for phenol and tocopherol compound extraction were obtained using ethanol and water solvents, respectively. With a high antioxidant power, chili pepper can find a wide application in food, pharmaceutical, and cosmetic industries.

The phenolic compounds, tocopherols, and phytosterols in the edible oil of guava (Psidium guava) seeds obtained by supercritical CO2 extraction

An edible oil was obtained from guava seeds by supercritical CO2 extraction. The oil was characterized by its fatty acid composition, physicochemical properties, and the contents of phenolic, miscellaneous, phytosterol, and tocopherol compounds. The oil, obtained with a yield of 8.6 ± 1.2 g oil/100 g guava seeds, had a high content of linoleic acid (78.5 %, w/w), followed by that of oleic acid (13.8 %, w/w). The guava seed oil had physicochemical properties comparable to those published in previous research, except for the low stability to oxidation. The chromatographic profile of the phenolic and miscellaneous compounds was dominated by vanillin (9.6 ± 0.3 mg/100 g oil) and cinnamaldehyde (9.4 ± 0.2 mg/100 g oil), followed by vanillic acid (3.9 ± 0.4 mg/100 g oil), cinnamic acid (2.4 ± 0.1 mg/100 g oil), and minor amounts of other phenolic aldehydes. Among the phytosterols and tocopherols, β-sitosterol (1048.9 ± 48.4 mg/100 g oil) and γ-tocopherol (82.6 ± 3.7 mg/100 g oil) were the most abundant. The low oxidative stability of the oil compared to that published in previous reports might reflect the high complexity of this matrix. This oil might have applications, directly or after blending with more stable edible oils.

Characterization of virgin walnut oils and their residual cakes produced from different varieties

This study addresses the composition and properties of different walnut varieties (Chandler, Hartley and Lara), in particular their virgin oils and residual cakes obtained by screw pressing employing different cultivars. Among nuts, walnut (Juglans regia L.) exhibits interesting nutritional value, mainly due to their high content in linoleic acid, phenolic and tocopherol compounds, which show antioxidant and other healthy properties. Valuable results related to fatty acid profile and minor components were observed. Virgin walnut oil is a rich source in linoleic acid (60–62%) and γ-tocopherol (517–554 mg/kg). Moreover, walnuts show a very high content in total phenolic compounds (10,045–12,474 mg/kg; as gallic acid), which contribute to a great antioxidant activity (105–170 mmol/kg for DPPH, and 260–393 mmol/kg for ORAC), being the hydrolysable tannins (2132–4204 mg/kg) and flavanols (796–2433 mg/kg) their main phenolic groups. Aldehydes account for the highest contribution to aromatic volatiles in virgin walnut oil (about 35% of total). As expected, polar phenolic compounds concentrate in the residual cake, after the separation of the oily phase, reaching a content of up to 19,869 mg/kg, leading to potential added value and applications as source of bioactive compounds to this by-product.

Chemical profiles and Sensory analysis of four varieties of olive oil cultivated in Morocco

To ensure olive oil quality, a combination of physico-chemical and sensory methods is necessary. Utility and importance of these methods in the international norm for olive oil are presente . The aim of the present study is to evaluate the chemical characterization of main compounds and Sensory analysis of four extra virgin olive oil varieties grown in Morocco (Moroccan Picholine, Picual, Arebiquine and Koroneiki). Quality parameters monitored over the study were acidity, peroxide value, UV absorption (E232 and E270), tocopherol, fatty acid composition, total polyphenol and Rancimat test. Results show that the Koroneiki variety presents the highest concentrations of C18:1. This variety is also rich in phenolic and tocopherol compounds. In contrast, Arebquina oil shows the lowest contents of C18:1, phenolic and tocopherol compounds. This explains the low stability values for this cultivar. From the sensory results the Picholine, Picual and Koroneiki variety was characterized as fruity, but Arbequina variety did not meet the criteria of extra virgin oil.

Oxidative stability of olive oil during the thermal process: Effect of Pistacia khinjuk fruit oil

ABSTRACTThe oxidative stability of refined olive oil with incorporated Pistacia khinjuk fruit oil (PKFO; 0.5%, 1%, 2%, 5%, and 10%) during thermal processing at 170ºC for 8 h was evaluated. The conjugated diene values, carbonyl values, acid values, oil/oxidative stability indices, and total tocopherol content were measured during thermal processing. Olive oil containing 0.5% PKFO was identified as the most oxidative stable oil followed by oils containing 100 ppm TBHQ and 1, 5, 10, and 2% PKFO. No significant difference between samples of olive oil containing 100 ppm TBHQ and 1% PKFO was observed. Thus, it was concluded that PKFO at levels lower than 1% could provide stronger antioxidation activity in comparison with TBHQ (the strongest syntactic antioxidant used in the food industry). Moreover, reduction in tocopherol compounds during thermal processing was higher in olive oil containing TBHQ as compared to those in pure olive oil.

A multiphase experiment for the analysis of bioactive compounds in canola oil: Sources of error from field and laboratory

Multiphase designs are an effective technique to assess all sources of variation in an experiment; however they have not yet been widely applied to analytical chemistry. In this study a multiphase design was used to evaluate sources of error from the field and laboratory phases of an experiment involving canola growing, oil extraction, sample preparation, and analysis using high performance liquid chromatography coupled to diode array detection and tandem mass spectrometry (HPLC-DAD-MS/MS). Several classes of bioactive compounds ‒ tocopherols, carotenoids and sterols ‒ were measured in the canola (Brassica napus) oil from 64 different genotypes to be assessed for varietal and environmental influence. Other factors which might contribute to error were identified, incorporated into the design, and their associated error calculated and accounted for. The field and HPLC phases were the largest contributors to total error, with only small influences from the extraction and preparation phases. Likelihood ratio testing of the nested multiphase models proved that high precision was achieved by use of the multiphase design, and identified possible improvements for future laboratory work. In the first reported application of a multiphase design to multi-stage laboratory analyses, the design was shown to offer considerable advantages over traditional approaches particularly in reducing total sample number, time and cost of analysis, as well as more comprehensive monitoring of experimental error.

Phytochemical composition, cellular antioxidant capacity and antiproliferative activity in mango (Mangifera indica L.) pulp and peel

AbstractCellular antioxidant activity (CAA) and inhibition of hepato‐cellular carcinoma (HepG2) proliferation were evaluated for the first time in the pulp and peel of mango cultivars. Comparatively, peel had high flavonoids and tocopherols content and showed significant antioxidant activity. Among all the studied cultivars, the Xiao Tainong peel was predominant with highest fistein, mangiferin and alpha‐tocopherol content and significant cellular antioxidant activity value 2986 ± 380 μmol QE/100 g FW. The HepG2 cells antiproliferation was maximum in the peel of Da Tainong and pulp of Aozhou with lowest EC50 values, 2.35 ± 0.65 (peel) and 185.4 ± 10.9 (pulp) mg mL−1, in a dose‐dependent manner. Negative associations of flavonoids and tocopherol compounds with CAA and antiproliferative activity in mango confirmed synergistic, additive or antagonistic actions of phytochemicals. The current study suggests that mango peel could be used as a value added ingredient or functional food and may contribute considerably to promote consumer health.

More than 170 polyunsaturated tocopherol-related compounds in a vitamin E capsule: Countercurrent chromatographic enrichment, gas chromatography/mass spectrometry analysis and preliminary identification of the potential artefacts

Tocopherols and tocotrienols (usually summed up as vitamin E) are a class of structurally related natural antioxidants. Commonly, only some of the eight classic representatives (four tocopherols and four tocotrienols) are found with varied composition in food. In this study we fractionated 230mg oil from commercial vitamin E supplement capsules by countercurrent chromatography (CCC) and subsequent analysis by gas chromatography with mass spectrometry (GC/MS) of silylated CCC fractions showed that these eight isomers represented only about 70% of total tocopherol compounds. Detailed analysis enabled the detection of 161T3 isomers (α-, γ- and δ-T3) along with 18 tetra- and several penta-unsaturated isomers (tocools), two tocomonoenol isomers, and several degradation products with shorter isoprenoid side chain (apo-tocools). Altogether, over 170 tocool compounds, most likely artefacts which originated from an inappropriate oil refining process were described in this study. Silver ion high performance liquid chromatography (Ag+-HPLC) was used to separate one fraction rich in γ-T3 into four peaks each consisting of at least five peaks according to GC/MS. About ten γ-T3 isomers were also detected in rice bran oils from one producer bought retail in Germany.