Abstract:The content of a-tocopherol in pepper fruits (Capsicum annuum L.) and its stability during dehydration and storage were determined. Our data show that the three pepper varieties used in this study, regardless of stage of maturity, contained from 9000 to 10000 pg of a-tocopherol/g of oil (oleoresin). The a-tocopherol content in the fresh pepper and its dry matter was found to depend on the content of lipids which in turn depends on ripening stage and genetic variety factors. During dehydration the loss of a-toc… Show more
“…Due to their structure tocopherols insert into the amphipathic phospholipid bilayer of cellular membranes 1 , 3 , 10 , 11 . Thus, they are able to protect membrane lipids as well as photosynthetic organs and seeds from oxidative stress 1 , 12 , 13 and are widely spread in nature 1 , 14 . As they can only be synthesized by photosynthetic organisms and have many positive physiological impacts they are not only valuable but also essential nutrients for humans 7 – 9 , 15 .…”
Section: Introductionmentioning
confidence: 99%
“…As they can only be synthesized by photosynthetic organisms and have many positive physiological impacts they are not only valuable but also essential nutrients for humans 7 – 9 , 15 . Good sources for tocopherols in general are nuts, seeds and vegetable oils 1 , 14 . The most abundant naturally occurring tocopherol in photosynthetic tissues is α-tocopherol 7 , 16 , while seeds accumulate about 10–20 times more γ-tocopherol 13 .…”
Section: Introductionmentioning
confidence: 99%
“…The most abundant naturally occurring tocopherol in photosynthetic tissues is α-tocopherol 7 , 16 , while seeds accumulate about 10–20 times more γ-tocopherol 13 . High amounts of α-tocopherol can be found for example in wheat germ oil, sunflower oil, olive oil, hazelnuts, almonds or bell pepper whereas walnuts or pumpkin seeds are a very good source for γ-tocopherol 13 , 14 , 17 , 18 . Figure 1 ( a ) General structure of tocopherols with: R 1 , R 2 = CH 3 for α-tocopherol, R 1 = CH 3 , R 2 = H for β-tocopherol, R 1 = H, R 2 = CH 3 for γ-tocopherol and R 1 , R 2 = H for δ-tocopherol.…”
Tocopheryl fatty acid esters (TFAE) consist of tocopherols esterified to fatty acids, but only little is known about this substance class. In this study, twelve vegetable groups were screened on TFAE and contents of (free) tocopherols and TFAE were determined in red bell pepper, red chili pepper, cucumber and walnut (n = 5, respectively). Intact TFAE were separated by solid phase extraction from free tocopherols and analyzed by GC/MS. Highest TFAE values were determined in chili pepper (4.0–16 mg/100 g fresh weight, FW) and walnut (4.1–12 mg/100 g FW), followed by bell pepper (1.3–1.5 mg/100 g FW) and cucumber (0.06–0.2 mg/100 g FW). Contribution of TFAE to the total tocopherol content ranged from 7–84%. Neither the treatment with artificial digestion juices nor exposure to sunlight showed degradation of TFAE. This substance class might represent a hitherto overlooked storage form for free tocopherols in plants as they occur to be more stable. But as the ester bond in medium chain TFAE seems not to be fissile in the human body, they might not contribute in the same way as free tocopherols to the vitamin E activity of vegetables and might have to be determined separately.
“…Due to their structure tocopherols insert into the amphipathic phospholipid bilayer of cellular membranes 1 , 3 , 10 , 11 . Thus, they are able to protect membrane lipids as well as photosynthetic organs and seeds from oxidative stress 1 , 12 , 13 and are widely spread in nature 1 , 14 . As they can only be synthesized by photosynthetic organisms and have many positive physiological impacts they are not only valuable but also essential nutrients for humans 7 – 9 , 15 .…”
Section: Introductionmentioning
confidence: 99%
“…As they can only be synthesized by photosynthetic organisms and have many positive physiological impacts they are not only valuable but also essential nutrients for humans 7 – 9 , 15 . Good sources for tocopherols in general are nuts, seeds and vegetable oils 1 , 14 . The most abundant naturally occurring tocopherol in photosynthetic tissues is α-tocopherol 7 , 16 , while seeds accumulate about 10–20 times more γ-tocopherol 13 .…”
Section: Introductionmentioning
confidence: 99%
“…The most abundant naturally occurring tocopherol in photosynthetic tissues is α-tocopherol 7 , 16 , while seeds accumulate about 10–20 times more γ-tocopherol 13 . High amounts of α-tocopherol can be found for example in wheat germ oil, sunflower oil, olive oil, hazelnuts, almonds or bell pepper whereas walnuts or pumpkin seeds are a very good source for γ-tocopherol 13 , 14 , 17 , 18 . Figure 1 ( a ) General structure of tocopherols with: R 1 , R 2 = CH 3 for α-tocopherol, R 1 = CH 3 , R 2 = H for β-tocopherol, R 1 = H, R 2 = CH 3 for γ-tocopherol and R 1 , R 2 = H for δ-tocopherol.…”
Tocopheryl fatty acid esters (TFAE) consist of tocopherols esterified to fatty acids, but only little is known about this substance class. In this study, twelve vegetable groups were screened on TFAE and contents of (free) tocopherols and TFAE were determined in red bell pepper, red chili pepper, cucumber and walnut (n = 5, respectively). Intact TFAE were separated by solid phase extraction from free tocopherols and analyzed by GC/MS. Highest TFAE values were determined in chili pepper (4.0–16 mg/100 g fresh weight, FW) and walnut (4.1–12 mg/100 g FW), followed by bell pepper (1.3–1.5 mg/100 g FW) and cucumber (0.06–0.2 mg/100 g FW). Contribution of TFAE to the total tocopherol content ranged from 7–84%. Neither the treatment with artificial digestion juices nor exposure to sunlight showed degradation of TFAE. This substance class might represent a hitherto overlooked storage form for free tocopherols in plants as they occur to be more stable. But as the ester bond in medium chain TFAE seems not to be fissile in the human body, they might not contribute in the same way as free tocopherols to the vitamin E activity of vegetables and might have to be determined separately.
“…The amount of vitamin E in fruits and vegetables is affected by species, variety, maturity, growing conditions (weather, growing season, intensity of sunlight, and soil state), uneven distribution of tocopherols, and time and manner of harvesting (Bauernfeind, 1980). Even after harvest, variation in the vitamin E values is caused by many factors including processing procedures, storage time and conditions, sample preparation and variation in analytical methods (Booth, 1963;Booth and Bradford, 1963b;McLaughlin and Weihrauch, 1979;Kanner et al, 1979;Hamauzu and Chachin, 1995;Rupe´rez et al, 2001;Eitenmiller and Lee, 2004). In 1979, the first comprehensive compilation of the US Department of Agriculture (USDA) of the tocopherol and tocotrienol composition of foods was published by McLaughlin and Weihrauch (1979).…”
“…However when combined they exhibit an antioxidant synergistic effect. The relative high rPOSI of red-pepper seems to be because the presence of a natural cocktail of antioxidants at relative high critical concentration of ascorbic-acid, tocopherols, polyphenols and carotenoids [37], [39].Fig. 2Turkey red-meat lipid peroxidation as affected by ascorbic acid (AA) and catechin determined by MDA accumulation in stomach medium at pH 3.0, 37 °C, t=90 min.…”
Red-meat lipid peroxidation in the stomach results in postprandial oxidative stress (POS) which is characterized by the generation of a variety of reactive cytotoxic aldehydes including malondialdehyde (MDA). MDA is absorbed in the blood system reacts with cell proteins to form adducts resulting in advanced lipid peroxidation end products (ALEs), producing dysfunctional proteins and cellular responses. The pathological consequences of ALEs tissue damage include inflammation and increased risk for many chronic diseases that are associated with a Western-type diet. In earlier studies we used the simulated gastric fluid (SGF) condition to show that the in vitro generation of MDA from red meat closely resembles that in human blood after consumption the same amount of meat. In vivo and in vitro MDA generations were similarly suppressed by polyphenol-rich beverages (red wine and coffee) consumed with the meal. The present study uses the in vitro SGF to assess the capacity of more than 50 foods of plant origin to suppress red meat peroxidation and formation of MDA. The results were calculated as reducing POS index (rPOSI) which represents the capacity in percent of 100 g of the food used to inhibit lipid peroxidation of 200 g red-meat a POSI enhancer (ePOSI). The index permitted to extrapolate the need of rPOSI from a food alone or in ensemble such Greek salad, to neutralize an ePOSI in stomach medium, (ePOS–rPOSI=0). The correlation between the rPOSI and polyphenols in the tested foods was R2=0.75. The Index was validated by comparison of the predicted rPOSI for a portion of Greek salad or red-wine to real inhibition of POS enhancers. The POS Index permit to better balancing nutrition for human health.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
