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The hydrophilic and lipophilic antioxidant activities due to the main bioactive components present in Spanish tomato paste samples were studied, using standardized and fluorescent methods. After extraction, phenolic antioxidants (Folin-Ciocalteu method) and total antioxidant activity (TEAC assay) were evaluated, examining differences between hydrophilic and lipophilic extracts corresponding to different samples. Total fluorescence spectra of extracts (excitation-emission matrices, EEMs) were recorded in the front-face mode at two different ranges: 210–300 nm/310–390 nm, and 295–350 nm/380–480 nm, for excitation and emission, respectively, in the hydrophilic extracts. In the lipophilic extracts, the first range was 230–283 nm/290–340 nm, while the second range was 315–383 nm/390–500 nm for excitation and emission, respectively. EEMs from a set of 22 samples were analyzed by the second-order multivariate technique Parallel Factor Analysis (PARAFAC). Tentative assignation of the different components to the various fluorophores of tomato was tried, based on literature. Correlation between the antioxidant activity and score values retrieved for different components in PARAFAC model was obtained. The possibility of using EEMs-PARAFAC to evaluate antioxidant activity of hydrophilic and lipophilic compounds in these samples was examined, obtaining good results in accordance with the Folin-Ciocalteu and TEAC assays.

International audience; Foods containing polyunsaturated lipids are prone to oxidation. Designing food-grade hydrocolloidal encapsulation systems able to load lipophilic antioxidant molecules, such as tocopherols (vitamin E), is necessary to prevent oxidation and its deleterous consequences. In this study, we hypothesised that α-tocopherol molecules could incorporate in a host membrane composed of milk sphingomyelin (milk-SM) and performed a multi-scale biophysical study. The thermal properties of milk-SM bilayers with various molar proportions of α-tocopherol were characterised by differential scanning calorimetry (DSC), their structural properties were examined by X-ray diffraction (XRD). The miscibility between milk-SM and α-tocopherol was investigated in mixed Langmuir monolayers. The morphology of milk-SM sphingosomes was observed by confocal laser scanning microscopy (CLSM). We found that molecules of α-tocopherol inserted into the milk-SM bilayers and induced a physical desorganisation in the membrane packing, both in the ordered and fluid states. In the presence of α-tocopherol, the bilayers were no longer in a gel phase below the phase transition temperature Tm, but in the liquid ordered Lo phase. Furthermore, the sphingosomes formed elongated structures in presence of α-tocopherol as a result of membrane softening and changes in the bilayer curvature associated to membrane fusion. The findings of this work contribute in a better understanding of the capacity of milk-SM bilayers to incorporate guest molecules. Milk-SM sphingosomes loaded with tocopherols could be used to prevent oxidation in aqueous foods containing polyunsaturated lipids such as oil-in-water emulsions. © 2022 Elsevier Ltd

The effect of high hydrostatic pressure (HHP) (450–550–650 MPa/5–10–15 min) on the carotenoid profile of purees obtained from commercial tomato varieties (Maliniak, Cerise, Black Prince and Lima) was investigated. The carotenoids profile was analysed using high performance liquid chromatography (HPLC‐DAD). Photochemiluminescence (PCLACL), ferric‐reducing antioxidant power (FRAP) and cyclic voltammetry (CV) assays were used to determine the antioxidant capacity of the lipophilic extracts. The results demonstrated that at certain processing conditions, HHP distinctly enhanced antioxidant capacity of the studied material. A significant reduction in lycopene and β‐Carotene concentration was observed for all the HHP‐treated purees. In contrast, lutein found in the puree extracts of Cerise and Black Prince tomatoes was slightly affected at 550 MPa/5 min and 650 MPa/5 min. Among all the carotenoids studied, lutein strongly and significantly affected PCLACL and CV parameters. In contrast, lycopene had a negligible effect on the examined parameters.

Poultry protein hydrolysates (PPHs) are obtained as by-product of poultry slaughter industry using bio catalytic hydrolysis. These protein hydrolysates have good antioxidant properties, which make them potential functional ingredient to prevent the oxidation of meat derived products. However, protein hydrolysates have a poor solubility in lipid media. To increase the solubilisation in the lipid phase, thus improving antioxidant properties on the fatty acids, several esterification reactions were carried out using different alcohols. The reactions were monitored by LC–MS and the shift in antioxidant activity was assessed with hydrophilic and lipophilic ABTS assay. A good increase in the lipophilicity of the esterified PPHs is shown, proportional to the increase of the alcohol chain length. Accordingly, a significant increase of the lipophilic antioxidant activity, especially for longest chain alcohols, was also observed. These results indicated that the chemical esterification of PPHs with food-grade long chain alcohol can be a valuable approach to increase the lipophilic antioxidant properties of these products.

Pigments of pericarp and pulp of pink guava (Psidium guajava L. cv. ‘Criolla’) were investigated to elucidate the profile and the accumulation of main carotenoids during four stages of fruit ripening by using HPLC-DAD and APCI-MS/MS analysis. Seventeen carotenoids were identified, and changes in their profile during fruit ripening were observed. The carotenoids all-trans-β-carotene, 15-cis-lycopene, and all-trans-lycopene were present in all ripening stages, but all-trans-lycopene was found to be predominant (from 63% to 92% of total carotenoids) and responsible for the high lipophilic antioxidant capacity determined by spectrophotometric assays. By using light and transmission electron microscopy, the development of chromoplasts in pericarp and pulp was demonstrated. The accumulation of all-trans-lycopene and all-trans-β-carotene coincided with the development of large crystals; the chromoplasts of pink guava belong, therefore, to the crystalline type. Universidad de Costa Rica/[]/UCR/Costa Rica German Academy Exchange Service/[]/DAAD/Alemania UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA) UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Tecnología de Alimentos

Hypothesis Emulsions are common structures encapsulating lipophilic bioactive molecules, both in biological systems and in manufactured products. Protecting these functional molecules from oxidation is essential; Nature excels at doing so by placing antioxidants at the oil-water interface, where oxidative reactions primarily occur. We imagined a novel approach to boost the activity of antioxidants in designer emulsions by employing Pickering particles that act both as physical emulsion stabilizers and as interfacial reservoirs of antioxidants. Experiments α-Tocopherol or carnosic acid, two model lipophilic antioxidants, were entrapped in colloidal lipid particles (CLPs) that were next used to physically stabilize sunflower oil-in-water emulsions (“concept” Pickering emulsions). We first assessed the physical properties and stability of the CLPs and of the Pickering emulsions. We then monitored the oxidative stability of the concept emulsions upon incubation, and compared it to that of control emulsions of similar structure, yet with the antioxidant present in the oil droplet interior. Findings Both tested antioxidants are largely more effective when loaded within Pickering particles than when solubilized in the oil droplet interior, thus confirming the importance of the interfacial localization of antioxidants. This approach revisits the paradigm for lipid oxidation prevention in emulsions and offers potential for many applications.

Lipophilic compounds of seaweed have been linked to their potential bioactivity. Low polarity solvents such as chloroform, diethyl ether, n-hexane and their various combinations were used to extract the lipophilic antioxidants from brown seaweed namely Himanthalia elongata, Laminaria saccharina and Laminaria digitata. An equal-volume mixture of chloroform, diethyl ether and n-hexane (Mix 4) gave the highest total phenol (52.7 &plusmn, 1.93 to 180.2 &plusmn, 1.84 mg gallic acid equivalents/g), flavonoid (31.9 &plusmn, 2.65 to 131.3 &plusmn, 4.51 mg quercetin equivalents/g), carotenoid (2.19 &plusmn, 1.37 to 3.15 &plusmn, 0.91 &mu, g/g) and chlorophyll content (2.88 &plusmn, 1.08 to 3.86 &plusmn, 1.22 &mu, g/g) in the tested seaweeds. The extracts were screened for their potential antioxidant capacity and the extracts obtained from the selected solvents system exhibited the highest radical scavenging capacity against 2,2&prime, diphenly-1-picrylhydrazyl radical (EC50 98.3 &plusmn, 2.78 to 298.8 &plusmn, 5.81 mg/L) and metal ions (EC50 228.6 &plusmn, 3.51 to 532.4 &plusmn, 6.03 mg/L). Similarly, the same extract showed the highest ferric reducing antioxidant power (8.3 &plusmn, 0.23 to 26.3 &plusmn, 0.30 mg trolox equivalents/g) in all the seaweeds. Rapid characterization of the active extracts by liquid chromatography coupled with photodiode array detector and electrospray ionization tandem mass spectrometry (LC-PDA&ndash, ESI-MS/MS) identified cyanidin-3-O-glucoside, fucoxanthin, violaxanthin, &beta, carotene, chlorophyll a derivatives and chlorophyll b derivatives in the tested seaweed. The study demonstrated the use of tested brown seaweed as potential species to be considered for future applications in medicine, cosmetics and as nutritional food supplement.

In view of understanding the stability of sterilized &lsquo, Cara Cara&rsquo, juice during storage, the changes of specific quality parameters (flavonoid, carotenoid, vitamin C, soluble sugar and antioxidant activities) of &lsquo, juice were systematically investigated over the course of 16 weeks in storage at 4, 20, 30 and 40 &deg, C. Total flavonoid and carotenoid indexes showed slight degradation at each temperature, while vitamin C and soluble sugar degraded intensively, especially at 40 &deg, C storage with a great amount of HMF (5-hydroxymethylfurfural) accumulated. There were 29 carotenoids detected during storage, including carotenes and carotenoid esters. Carotenes were kept stable, while the degradations of carotenoid esters were fitted by biexponential function. Carotenoid ester group 2 contained epoxy structures that quickly decreased in the first four weeks at all storage temperatures, while the ester group 1 (belonged to &beta, cryptoxanthin ester) was degraded gradually. The 13- or 15-cis-lycopene, isomerized from all-(trans)-lycopene, increased with storage time at each temperature. Total flavonoid and carotenoid indexes in stored &lsquo, juice were positively correlated with hydrophilic and lipophilic antioxidant abilities.

The aim of this study is to evaluate the feasibility of edible oils co-encapsulation with antioxidants in a natural protein matrix obtained using the spray-drying method, and to demonstrate the long-term stability of microparticles. Sunflower and flaxseed oils were encapsulated in pea protein isolate (PP) with a hydrophilic antioxidant, propyl gallate (PG), and a lipophilic antioxidant, α-tocopherol (α-T). Samples with encapsulated oil and the corresponding unencapsulated oil were then stored at 25 °C for up to 10 months (300 days) to monitor the long-term oxidative stability. The results demonstrated that microencapsulation, the addition of antioxidants, as well as the nature of the oil all affected the oxidative stability of oils. The addition of PG made it possible the increase in oil stability during the total storage period, whereas α-T had a pro-oxidant effect and induced the decrease in oil resistivity to oxidation. The positive effect of PG was more pronounced for short storage times (t

Background: Lipophilic antioxidants in tomato (Solanum lycopersicum) fruits exert important functions in reducing the risk of human diseases. Here the effect of thermal processing on the antioxidant activity of lipophilic extracts from the commercial tomato hybrid 'Zebrino' was analysed. Carotenoid content and lipophilic antioxidant activity were determined and the ability of tomato extracts in rescuing cells from oxidative stress was assessed.; Results: Lipophilic antioxidant activity was completely retained after heat treatment and extracts were able to mitigate the detrimental effect induced by oxidative stress on different cell lines. Lycopene alone was able to rescue cells from oxidative stress, even if to a lower extent compared with tomato extracts. These results were probably due to the synergistic effect of tomato compounds in protecting cells from oxidative stress injury.; Conclusion: The current study provides valuable insights into the health effect of the dietary carotenoids present in fresh and processed tomato fruits. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

Supercritical assisted Liposome formation process (SuperLip) allows one-shot, continuous and reproducible production of liposomes. In this work, the optimization of Gas to Liquid Ratio of the Expanded Liquid (GLR-EL); i.e., the ratio between carbon dioxide flow rate and ethanol flow rate, is presented. It allows to control liposomes diameter from micrometric to nanometric range and the amount of Solvent Residue (SR) in the final suspension. Working at a GLR-EL lower than about 1.8, resulted in the production of micrometric and sub-micrometric L-α-phosphatidylcholine (PC) liposomes, with mean diameters ranging from 1729 ± 733 nm to 878 ± 170 nm; whereas, working at larger GLRs-EL nanometric liposomes, with diameters down to about 139 ± 49 nm were produced. Liposomes produced at GLR-EL 6.0 were loaded with a hydrophilic compound: an antibiotic, vancomycin, or a lipophilic antioxidant, farnesol. Liposome diameters were again nanometric down to 126 ± 35 nm for farnesol loaded vesicles and encapsulation efficiencies (EE) were up to 76.7 ± 1.9%. The mean size of vancomycin loaded liposomes was 250 ± 93 nm and EE up to 74.0 ± 1.1% were obtained. SR down to 10 ppm were obtained on loaded vesicles, improving the possibility of their use for pharmaceutical applications.

The biological activity of carotenoids depends on their bioaccessibility and solubilization in the gastrointestinal tract. These compounds are poorly dispersed in the aqueous media of the digestive tract due to their lipophilic nature. Thus, it is important to analyze the extent to which some factors, such as the food matrix and food processing, may improve their bioaccessibility. Beverages formulated with a blend of fruit juices and water (WB), milk (MB) or soymilk (SB) were treated by high-intensity pulsed electric fields (HIPEF) (35 kV cm with 4 μs bipolar pulses at 200 Hz for 1800 μs), high-pressure processing (HPP) (400 MPa at 40°C for 5 min) or thermal treatment (TT) (90°C for 1 min) in order to evaluate the influence of food matrix and processing on the bioaccessibility of carotenoids and on the lipophilic antioxidant activity (LAA). The bioaccessibility of these compounds diminished after applying any treatment (HIPEF, HPP and TT), with the exception of cis-violaxanthin + neoxanthin, which increased by 79% in HIPEF and HPP beverages. The lowest carotenoid bioaccessibility was always obtained in TT beverages (losses up to 63%). MB was the best food matrix for improving the bioaccessibility of carotenoids, as well as the LAA. The results demonstrate that treatment and food matrix modulated the bioaccessibility of carotenoids as well as the lipophilic antioxidant potential of beverages. Additionally, HIPEF and HPP could be considered as promising technologies to obtain highly nutritional and functional beverages., This research was supported by the Ministerio de Ciencia e Innovación (Spain), reference AGL2006-12758-C02-02/ALI and AGL2006-12758-C02-01/ALI. María Janeth Rodríguez-Roque thanks the Comissionat per a Universitats i Recerca, del Departament d’Innovació, Universitats i Empresa de la Generalitat de Catalunya and European Social Fund for the predoctoral grant. Dr Begoña de Ancos thanks the Ministerio de Economía y Competitividad (Spain) for its support through the proyect AGL2013-46326-R. Prof. Olga Martín-Belloso thanks the Institució Catalana de Recerca i Estudis Avançats (ICREA) for the Academia Award 2008.

Vitamin E (α-tocopherol) is recognised as a key essential lipophilic antioxidant in humans protecting lipoproteins, PUFA, cellular and intra-cellular membranes from damage. The aim of this review was to evaluate the relevant published data about vitamin E requirements in relation to dietary PUFA intake. Evidence in animals and humans indicates a minimal basal requirement of 4–5 mg/d of RRR-α-tocopherol when the diet is very low in PUFA. The vitamin E requirement will increase with an increase in PUFA consumption and with the degree of unsaturation of the PUFA in the diet. The vitamin E requirement related to dietary linoleic acid, which is globally the major dietary PUFA in humans, was calculated to be 0·4–0·6 mg of RRR-α-tocopherol/g of linoleic acid. Animal studies show that for fatty acids with a higher degree of unsaturation, the vitamin E requirement increases almost linearly with the degree of unsaturation of the PUFA in the relative ratios of 0·3, 2, 3, 4, 5 and 6 for mono-, di-, tri-, tetra-, penta- and hexaenoic fatty acids, respectively. Assuming a typical intake of dietary PUFA, a vitamin E requirement ranging from 12 to 20 mg of RRR-α-tocopherol/d can be calculated. A number of guidelines recommend to increase PUFA intake as they have well-established health benefits. It will be prudent to assure an adequate vitamin E intake to match the increased PUFA intake, especially as vitamin E intake is already below recommendations in many populations worldwide.

The purpose of this study was to measure the antioxidant activity (AOA) of tocopherols and tocotrienols by using photochemiluminescence (PCL). This method enables to detect total lipophilic antioxidants. The AOA of all vitamin E isomers depended on number and position of methyl groups in the chroman ring. Correlation between the AOA and the redox potential and the biological activity of the tocochromanols was observed. The second aim was to analyse different kinds of wheat, vegetable oils, milk and milk cream on their antioxidant capacity (AOC) by using PCL and α-TEAC. The contents of vitamin E and carotenoids were analysed by HPLC. Correlations between the sum of carotenoids and vitamin E and the AOC were detected. Based on high vitamin E contents, the oils had the highest and in contrast, the product macaroni showed the lowest AOC. A concentration-dependent effect was observed in both assays, PCL and α-TEAC.

Polyphenols are natural compounds showing a variety of health-promoting effects. Unfortunately, due to low lipid solubility, their applications in the pharmaceutical, food, and cosmetic industries are limited. With the aim of obtaining novel lipophilic derivatives, the present study reports the synthesis of a series of phenethyl trifluoroacetate esters containing up to two hydroxyl groups in the aromatic ring. Experimental logP values confirmed a greater lipophilicity of the novel compounds compared to the parent compounds. The radical scavenging capacity of all phenethyl trifluoroacetate esters was evaluated by in vitro assays (ABTS, DPPH) and in cultured cells (L6 myoblasts and THP-1 leukemic monocytes) using 2′,7′-dichlorodihydrofluorescein diacetate. These data revealed that the esters showed a good antioxidant effect that was strictly dependent on the grade of hydroxylation of the phenyl ring. The lack of toxicity, evaluated by the MTT assay and proliferation curves, makes these trifluoroacetates attractive derivatives for pharmaceutical, food, and cosmetic applications.

Maize ( Zea mays L.) germs are by-products from the milling industry. The objective of this work was to compare the phenolic and lipophilic antioxidant fractions of yellow and white corn varieties, provided by Corn Valley S.r.l. (Piumbega, Mantova, Italy) and among the raw materials most processed by the company. The phenolic fraction, extracted with ultrasound-assisted extraction, alone and in combination with chemical and enzymatic hydrolyses, was analyzed with high-performance thin-layer chromatography and reversed-phase high-performance liquid chromatography-diode array detector. Among the various extraction techniques used, the combination of sonication and alkaline hydrolysis proved to be an effective method for the extraction of phenolic compounds from yellow and white germs, with the highest ferulic acid concentrations (636.54 ± 3.71 and 569.23 ± 1.69 mg FA/g dried extract, respectively), total phenolic contents (844.5 ± 64.6 and 742.8 ± 15.44 mg gallic acid equivalents/g dried extract, respectively), and the best antioxidant activity (14.33 ± 0.48 and 11.41 ± 1.1 µg/mL, respectively). The lipophilic fraction, extracted using supercritical carbon dioxide was analyzed by gas chromatography-mass spectrometry. The unsaponifiable fractions were found to be 2.41% ± 0.24% in yellow corn and 1.85% ± 0.08% in white corn; β-sitosterol, campesterol, and stigmasterol were identified as the main phytosterols characterizing both lipophilic extracts which showed the most effective antioxidant activity (1.29 ± 0.26 mg/mL and 1.33 ± 0.21 mg/mL, respectively) compared with the control. Finally, the phenolic and lipophilic extracts obtained from maize by-products may be reintroduced into the health-oriented market as extracts enriched of high-added value biomolecules with antioxidant activity both as active molecules and as additives of natural origin.

Ruminant meat is considered an excellent source of proteins, dietary fatty acids and essential minerals. Grilling is a popular cooking method; however, the high temperatures employ could modify the grilled meat quality and safety. In this study, the effects of novel beer-based marinades infused with herbs and spices on the quality, safety, and sensory perception of grilled beef and moose meat is examined. Unmarinated meat showed high content of volatile lipid oxidation and Maillard reaction products compared to the marinated samples, which contained higher number and abundance of terpenes and sulfur based compounds. Strong relationships between Maillard products and heterocyclic amines formation, as well as between volatile terpenes and the lipophilic antioxidant activity, were observed in the grilled meats. The findings suggest the unfiltered beer-based marinades were effective in reducing lipid oxidation and Maillard reaction compounds formation, while improving the nutritional quality, safety and sensory preference of grilled ruminant meats.

Yellow and white maize kernels, masas, tortillas, and nejayote solids were analyzed in terms of lutein, zeaxanthin, cryptoxanthin, β-carotene, and lipophilic antioxidant (AOX) capacity. The germplasm analyzed included two normal yellow maize, two high-carotenoid genotypes, and one white for comparison purposes. In general, the yellow maize required 34% more lime-cooking time compared with the white counterpart. Lime-cooking significantly changed the extractability of carotenoids in masa and tortillas. No carotenoids were detected in the steepwater or nejayote. The lipophilic AOX activity increased 280-fold from kernel to masa, but only 70% was retained in the baked tortillas. When masa was baked into tortillas, less than 10% of the carotenoids were retained because of the high temperatures used during baking. Interestingly, tortillas made with the maize kernels with the highest carotenoid content did not have the highest amount of these phytochemicals. Therefore, maize varieties should be evaluat...

BACKGROUND: Carotenoids are important antioxidant compounds in the human diet. Due to their constrained polyene structure, carotenoids can exist in cis and trans isomeric form. In ketchups and tomato juices, all-trans isomeric forms are predominant. OBJECTIVE: The aim of this study was to compare the carotenoid content and lipophilic antioxidant capacity of organic and conventional tomato-based products (tomato juices and ketchups) available on the market. METHODS: Liquid chromatography coupled to mass spectrometry in tandem mode (LC-MS/MS) and HPLC-UV were used for the identification and quantification of individual carotenoids. RESULTS: A comparative analysis of ketchups and tomato juices produced by conventional and organic systems showed statistically higher levels (P

The effect of hyperbaric treatments on major hydrophilic and lipophilic antioxidants and antioxidant activity in tomato fruit, using ORAC and TEAC assays, was studied. Early breaker stage greenhouse grown tomatoes were subjected to different pressure and temperature conditions, including 0.1 (ambient atmospheric pressure, control), 0.3, 0.5, 0.7 and 0.9 MPa at 20 °C, and 0.1 MPa at 13 °C (cold treatment) for 4 days, followed by ripening at 20 °C for 5 and 10 days. Hyperbaric treatment significantly affected lycopene content by inhibiting, then enhancing its accumulation during treatment and ripening, respectively. In general, ascorbic acid and total phenolic contents increased as time progressed but generally were not affected by hyperbaric pressure treatment. All antioxidants were found in lower concentrations in tomatoes treated at 13 °C. The trend in antioxidant activity obtained from both ORAC and TEAC assays was generally similar. No significant effect of hyperbaric treatment on lipophilic antioxidant (LAA) and hydrophilic antioxidant (HAA) was observed compared with control tomatoes at 13 and 20 °C. However, the ORAC assay showed that hyperbaric treated tomatoes had significantly higher HAA than 13 °C treated tomatoes. Overall, hyperbaric treatment at 20 °C has potential to extend tomato shelf-life during short treatment durations without adverse impact on quality during ripening.

Food product based on gac fruit ( Momordica cochinchinensis Spreng. ) arils have a high potential due to the high carotenoids content of this fruit. Drying is a key preparation step for carotenoids extraction from gac fruit in a economically viable process. The impact of different drying technics, temperature, final product moisture content on the carotenoid content, hydrophilic and lipophilic antioxidant activity (evaluated with three methods) and color of the gac arils is discussed based on laboratory scale experimental tests. The results highlight an optimal temperature between 50 °C and 60 °C to conserve the color, the carotenoid content and the antioxidant activity. Also, these properties are better preserved by limiting the drying to dry based moisture content between 15% and 18% while the advantages of drying for further processing and for refrigerated conservation for a few months are achieved.

Lipophilic antioxidants are essential components of plant defense against stressful conditions. The response of carotenoids and tocols to water deficit and sulfur fertilization was investigated in durum wheat cultivars. The amounts of tocols and carotenoids were evaluated in both whole meal and semolina samples. Differences among cultivars were observed. Simeto cultivar showed a significant effect of water regime on whole meal and semolina carotenoids, with about 20% and 15% increase, respectively. Also tocols and tocotrienols of Simeto were positively affected by water stress (about 10% increase and 15% increase in whole meals and semolinas). Sulfur fertilization positively impacted mainly Ofanto whole-grain and semolina carotenoids, semolina tocols, and tocotrienols. In conclusion, water deficit occurring under a Mediterranean environment was responsible for an improvement of lipophilic antioxidant content in durum wheat; in contrast sulfur supplementation did not improve the response of the antioxidant pool under water deficit.

Recently, we proposed an oxygen radical absorbance capacity method that directly quantifies the antioxidant's scavenging capacity against free radicals and evaluated the radical scavenging abilities for water soluble antioxidant compounds. In this study, we determined the radical scavenging abilities of lipophilic antioxidants which were solubilized by cyclodextrin in water. Commonly employed fluorescence-based method measures the antioxidant's protection capability for the fluorescent probe, while we directly quantify free-radical level using electron paramagnetic resonance spin trapping technique. In addition, the spin trapping-based method adopted controlled UV-photolysis of azo-initiator for free radical generation, but in fluorescence-based method, thermal decomposition of azo-initiator was utilized. We determined the radical scavenging abilities of seven well-known lipophilic antioxidants (five flavonoids, resveratrol and astaxanthin), using methylated β-cyclodextrin as a solubilizer. The results indicated that the agreement between spin trapping-based and fluorescence-based values was only fair partly because of a large variation in the previous fluorescence-based data. Typical radical scavenging abilities in trolox equivalent unit are: catechin 0.96; epicatechin 0.94; epigallocatechin gallate 1.3; kaempferol 0.37; myricetin 3.2; resveratrol 0.64; and astaxanthin 0.28, indicating that myricetin possesses the highest antioxidant capacity among the compounds tested. We sorted out the possible causes of the deviation between the two methods.

Twenty-four cultivars of loquat fruit (Eriobotrya japonica Lindl.) were analyzed for the content of phenolics, vitamin C and carotenoids, and antioxidant activity with the aim of determining how the accumulation of bioactive compounds is related to the antioxidant activity. Results showed that the content of phenolics, vitamin C and carotenoids varied with cultivars, ranging from 59.55 to 132.13 mg/100 g fresh weight (FW), from 6.60 to 8.64 mg/100 g FW and from 46.89 to 2,699.06 µg/100 g FW, respectively. The determination of hydrophilic antioxidant activity (HAA) and lipophilic antioxidant activity (LAA) showed that a major contribution of total antioxidant activity (TAA) was due to HAA. The content of hydrophilic phenolics was positively correlated with both HAA and TAA, while the content of lipophilic phenolics or carotenoids was correlated positively with LAA and TAA. These data indicated that the presence of large quantity of phenolics could be the major contributor to HAA, while carotenoids and other compounds were associated with LAA. PRACTICAL APPLICATIONS Fruits not only can provide carbohydrates and minerals necessary for mankind, but also contain much antioxidant compounds. Interests in bioactive compounds and antioxidant activities of fruits had increased greatly because of their possible role in human health. In this study, phenolics content, vitamin C content, carotenoids content and hydrophilic and lipophilic antioxidant activities in vitro of loquat fruits (Eriobotrya japonica Lindl.) were investigated. The results showed that loquat fruits are valuable resources of antioxidants such as phenolics, vitamin C and carotenoids. A major contribution of total antioxidant activity was due to hydrophilic antioxidant activity. Phenolics could be the major contributor to hydrophilic antioxidant activity, while carotenoids and other compounds may be the major contributors to lipophilic antioxidant activity. We believe that these results may provide theoretical basis for utilization of loquat fruits as the potential source of natural antioxidants.

Major antioxidants and antioxidant activity in eight varieties of tomatoes were determined. Hydrophilic and lipophilic antioxidant activity (HAA and LAA) was determined by the ABTS assay and ascorbic acid and carotenoid contents were determined by HPLC-DAD. The HAA has far more significant impact on total antioxidant activity (83%) as compared with LAA. HAA was increasing during all ripening stages and was strongly correlated with ascorbic acid content ( r = 0.83). During the ripening the LAA was increasing till the III. stage of maturity and then decreased. The main carotenoids determined in the red-fruit tomatoes were lycopene, β-carotene and lutein. The content of lycopene has been increasing equally during the ripening. β-Carotene and lutein were intensively synthesized between the I. and II. stage of maturity. Among ascorbic acid, α-tocopherol, lycopene, β-carotene and lutein standards ascorbic acid was determined as the most efficient antioxidant followed by α-tocopherol and β-carotene. Antioxidant activity of ascorbic acid, α-tocopherol, β-carotene and lutein grew equally with increasing concentration, however lycopene was the most effective in its lowest concentration. The analysis of two-component mixtures showed significant synergism between lycopene-lutein, lycopene-β-carotene and α-tocopherol-β-carotene.

The comparison of lycopene content and lipophilic antioxidant capacity was explored among pink guava fruit and by-products of its puree production industry namely refiner, siever and decanter. Lycopene content was measured using both UV–vis spectrophotometer and high performance liquid chromatography (HPLC) methods. Atmospheric pressure chemical ionization liquid chromatography–mass spectrometry (APCI-LC–MS) was applied in confirming the studied compound. Two assays were employed to determine the lipophilic antioxidant capacities namely lycopene equivalent antioxidant capacity (LEAC) and -carotene bleaching assays. Lycopene content and antioxidant capacity were in the order of fruits > decanter > siever > refiner. Decanter exhibited the highest lycopene content and antioxidant among the studied by-products. It also gave a significant higher (p < 0.05) lycopene content than pink guava fruit based on the wet basis. There was a significant correlation between lycopene content and LEAC. All samples had a good antioxidant activity in -carotene bleaching assay but negatively correlated to lycopene content. Decanter was found to be the highest in lycopene content (17 mg/100 g dry basis) and antioxidant capacity (22mol LE/100 g dry basis) among the by-products. This by-product of pink guava puree industry can be a potential source of lycopene and antioxidant compounds. © 2010 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.