Edible oils are the major natural dietary sources of tocopherols and tocotrienols, collectively known as tocols. Plant foods with low lipid content usually have negligible quantities of tocols. ...However, seeds and other plant food processing by-products may serve as alternative sources of edible oils with considerable contents of tocopherols and tocotrienols. Tocopherols are among the most important lipid-soluble antioxidants in food as well as in human and animal tissues. Tocopherols are found in lipid-rich regions of cells (e.g., mitochondrial membranes), fat depots, and lipoproteins such as low-density lipoprotein cholesterol. Their health benefits may also be explained by regulation of gene expression, signal transduction, and modulation of cell functions. Potential health benefits of tocols include prevention of certain types of cancer, heart disease, and other chronic ailments. Although deficiencies of tocopherol are uncommon, a continuous intake from common and novel dietary sources of tocopherols and tocotrienols is advantageous. Thus, this contribution will focus on the relevant literature on common and emerging edible oils as a source of tocols. Potential application and health effects as well as the impact of new cultivars as sources of edible oils and their processing discards are presented. Future trends and drawbacks are also briefly covered.
Flavonoids display a broad range of health-promoting bioactivities. Among these, their capacity to act as antioxidants has remained most prominent. The canonical reactive oxygen species ...(ROS)-scavenging mode of the antioxidant action of flavonoids relies on the high susceptibility of their phenolic moieties to undergo oxidation. As a consequence, upon reaction with ROS, the antioxidant capacity of flavonoids is severely compromised. Other phenol-compromising reactions, such as those involved in the biotransformation of flavonoids, can also markedly affect their antioxidant properties. In recent years, however, increasing evidence has indicated that, at least for some flavonoids, the oxidation of such residues can in fact markedly enhance their original antioxidant properties. In such apparent paradoxical cases, the antioxidant activity arises from the pro-oxidant and/or electrophilic character of some of their oxidation-derived metabolites and is exerted by activating the Nrf2-Keap1 pathway, which upregulates the cell's endogenous antioxidant capacity, and/or, by preventing the activation of the pro-oxidant and pro-inflammatory NF-κB pathway. This review focuses on the effects that the oxidative and/or non-oxidative modification of the phenolic groups of flavonoids may have on the ability of the resulting metabolites to promote direct and/or indirect antioxidant actions. Considering the case of a metabolite resulting from the oxidation of quercetin, we offer a comprehensive description of the evidence that increasingly supports the concept that, in the case of certain flavonoids, the oxidation of phenolics emerges as a mechanism that markedly amplifies their original antioxidant properties. An overlooked topic of great phytomedicine potential is thus unraveled.
•Pronase and Viscozyme treatment changed the ratio of soluble to insoluble-bound phenolics.•Viscozyme was more effective than Pronase in releasing phenolic compounds.•Procyanidin dimer B was ...extracted with Viscozyme but not upon Pronase treatment.•Phenolics served as inhibitors of alpha-glucosidase and lipase.•Phenolics may act in prevention and/or management of diabetes and obesity.
Phenolics in food and agricultural processing by-products exist in the soluble and insoluble-bound forms. The ability of selected enzymes in improving the extraction of insoluble-bound phenolics from the starting material (experiment I) or the residues containing insoluble-bound phenolics (experiment II) were evaluated. Pronase and Viscozyme improved the extraction of insoluble-bound phenolics as evaluated by total phenolic content, antioxidant potential as determined by ABTS and DPPH assays, and hydroxyl radical scavenging capacity, reducing power as well as evaluation of inhibition of alpha-glucosidase and lipase activities. Viscozyme released higher amounts of gallic acid, catechin, and prodelphinidin dimer A compared to Pronase treatment. Furthermore, p-coumaric and caffeic acids, as well as procyanidin dimer B, were extracted with Viscozyme but not with Pronase treatment. Solubility plays an important role in the bioavailability of phenolic compounds, hence this study may assist in better exploitation of phenolics from winemaking by-products as functional food ingredients and/or supplements.
The INFOGEST protocol creation was a watershed for phenolic bioaccessibility studies. Because of this important initiative to standardize bioaccessibility studies, data comparisons between different ...laboratories are now expedited. It has been eight years since the INFOGEST protocol creation, and three from the latest update. However, the current status in terms of phenolic bioaccessibility and how far different laboratories are from reaching a consensus are still unrevealed. In this sense, this narrative review considered an evaluation of different studies that applied the INFOGEST protocol to investigate the bioaccessibility of phenolic compounds. The central objective was to compile the main findings and consensus and to identify possible gaps and future opportunities. This approach intends to further facilitate the use of this protocol by professionals in the field of food science and technology and related areas, generating a reflection on the actual level of standardization of the method. Despite the differences in phenolic compounds from diverse food matrices, and their peculiar behavior, some trends could be elucidated, in terms of phenolic release, stability, and/or transformation upon in vivo digestion. In contrast, there was no general consensus regarding sample preparation, how to report results and the form to calculate bioaccessibility, making it difficult to compare different studies. There is still a long road to effectively standardize the results obtained for phenolic bioaccessibility using the INFOGEST protocol, which is also an opportunity in terms of food analysis that can impact the food industry, especially for the development of nutraceuticals and functional foods.
•First report on the contribution of free, esterified and insoluble-bound phenolics in lentils.•Phenolic acids, flavonoids and proanthocyanidins were identified and quantified using ...HPLC-DAD-ESI-MSn.•Flavonoids made the highest contribution to the phenolic content of lentils.•Phenolics of lentils (0.1 mg/mL) were effective in inhibiting the DNA strand break (up to 91.7%).•Insoluble-bound phenolics (0.02 mg/mL) had the highest effect against LDL peroxidation among fractions tested.
Free, esterified, and insoluble-bound phenolics were extracted from selected lentil cultivars. Total phenolics, flavonoids and proanthocyanidin contents were determined. Catechin, epicatechin and procyanidins B were predominant in all fractions of all tested samples as evaluated using HPLC-DAD-ESI-MSn. Methyl vanillate, procyanidin dimer A, and prodelphinidin dimer A were identified and quantified in lentils for the first time. Procyanidin dimer A was detected only in the insoluble-bound form, methyl vanillate was present in the esterified and insoluble-bound one and prodelphinidin dimer A was found in all forms. The presence of unrevealed compounds present only in the insoluble-bound form shows that ignoring the presence of phenolics linked to the cell wall of lentils may underestimate their potential health benefits. The antioxidant activities and the inhibition of cupric ion-induced human low-density lipoprotein peroxidation and peroxyl radical induced supercoiled plasmid DNA strand scission demonstrated that lentil seeds may be considered as a functional food.
Vitamin E comprises a group of vitamers that includes tocopherols and tocotrienols. They occur in four homologues according to the number and position of methyl groups attached to the chromanol ring. ...Vitamin E, a liposoluble antioxidant, may participate as an adjuvant in the prevention and treatment of cardiovascular, neurological, and aging-related diseases. Furthermore, vitamin E has applications in the food industry as a natural additive. In this contribution, the most recent information on the dietary sources of vitamin E, including common, novel, and unexplored sources, is presented. Common edible oils, such as those of corn, olive, palm, rice bran, and peanut, represent the most prominent sources of vitamin E. However, specialty and underutilized oils such as those obtained from tree nuts, fruit seeds, and by-products, emerge as novel sources of this important micronutrient. Complementary studies should examine the tocotrienol content of vitamin E dietary sources to better understand the different biological functions of these vitamers.
Display omitted
•Centennial Anniversary of Vitamin E Discovery.•Updated database on the content of tocopherols and tocotrienols (tocols).•Analytical methods for identification and quantification of tocols.•Common, specialty and underutilized edible oils as sources of tocols.•Cereals, legume seeds, animal-derived products, wild plants and edible flowers.
Polycyclic aromatic hydrocarbons (PAHs) are chemical compounds comprised of carbon and hydrogen molecules in a cyclic arrangement. PAHs are associated with risks to human health, especially ...carcinogenesis. One form of exposure to these compounds is through ingestion of contaminated food, which can occur during preparation and processing involving high temperatures (e.g., grilling, smoking, toasting, roasting, and frying) as well as through PAHs present in the soil, air, and water (i.e., environmental pollution). Differently from changes caused by microbiological characteristics and lipid oxidation, consumers cannot sensorially perceive PAH contamination in food products, thereby hindering their ability to reject these foods. Herein, the occurrence and biological effects of PAHs were comprehensively explored, as well as analytical methods to monitor their levels, legislations, and strategies to reduce their generation in food products. This review updates the current knowledge and addresses recent regulation changes concerning the widespread PAHs contamination in several types of food, often surpassing the concentration limits deemed acceptable by current legislations. Therefore, effective measures involving different food processing strategies are needed to prevent and reduce PAHs contamination, thereby decreasing human exposure and detrimental health effects. Furthermore, gaps in literature have been addressed to provide a basis for future studies.
Legume seeds are rich sources of protein, fiber, and minerals. In addition, their phenolic compounds as secondary metabolites render health benefits beyond basic nutrition. Lowering apolipoprotein B ...secretion from HepG2 cells and decreasing the level of low-density lipoprotein (LDL)-cholesterol oxidation are mechanisms related to the prevention of cardiovascular diseases (CVD). Likewise, low-level chronic inflammation and related disorders of the immune system are clinical predictors of cardiovascular pathology. Furthermore, DNA-damage signaling and repair are crucial pathways to the etiology of human cancers. Along CVD and cancer, the prevalence of obesity and diabetes is constantly increasing. Screening the ability of polyphenols in inactivating digestive enzymes is a good option in pre-clinical studies. In addition, in vivo studies support the role of polyphenols in the prevention and/or management of diabetes and obesity. Soybean, a well-recognized source of phenolic isoflavones, exerts health benefits by decreasing oxidative stress and inflammation related to the above-mentioned chronic ailments. Similar to soybeans, chickpeas are good sources of nutrients and phenolic compounds, especially isoflavones. This review summarizes the potential of chickpea as a substitute for soybean in terms of health beneficial outcomes. Therefore, this contribution may guide the industry in manufacturing functional foods and/or ingredients by using an undervalued feedstock.
Carotenoid pigment content is an important quality trait as it confers a natural bright yellow color to pasta preferred by consumers (whiteness vs. yellowness) and nutrients, such as provitamin A and ...antioxidants, essential for human diet. The main goal of the present review is to summarize the knowledge about the genetic regulation of the accumulation of pigment content in durum wheat grain and describe the genetic improvements obtained by using breeding approaches in the last two decades. Although carotenoid pigment content is a quantitative character regulated by various genes with additive effects, its high heritability has facilitated the durum breeding progress for this quality trait. Mapping research for yellow index and yellow pigment content has identified quantitative trait loci (QTL) on all wheat chromosomes. The major QTL, accounting for up to 60%, were mapped on 7L homoeologous chromosome arms, and they are explained by allelic variations of the phytoene synthase (
PSY
) genes. Minor QTL were detected on all chromosomes and associated to significant molecular markers, indicating the complexity of the trait. Despite there being currently a better knowledge of the mechanisms controlling carotenoid content and composition, there are gaps that require further investigation and bridging to better understand the genetic architecture of this important trait. The development and the utilization of molecular markers in marker-assisted selection (MAS) programs for improving grain quality have been reviewed and discussed.
•Chia seed meal was a rich source bioactive phenolics based on HPLC-DAD-MS/MS data.•Rosmarinic acid and daidzein were the major phenolics present.•Procyanidin dimers (A, B1, B2, and B3) were ...identified for the first time in chia.•Chia phenolics inhibited lipase and α-glucosidase activity in vitro.•Chia phenolics prevented human LDL-cholesterol oxidation and DNA damage in vitro.
Phenolics exist in the soluble and insoluble-bound forms. In this research, free, esterified and insoluble-bound phenolics of defatted chia seeds were evaluated for their antioxidant activity using in vitro methods, namely ABTS+, DPPH and HO scavenging capacity assays. Their effect in a β-carotene linoleate system, reducing power and metal chelation activities were also determined. Furthermore, inhibition of activities against pancreatic lipase, α-glucosidase as well as LDL-cholesterol oxidation as well as DNA damage induced by peroxyl and hydroxyl radicals were examined. The free fraction was the predominant form of phenolics. HPLC-DAD-MS/MS analysis led to the identification of 27 phenolics belonging to phenolic acids, flavonoids and proanthocyanidins. Procyanidin dimers (A, B1, B2, and B3) were identified for the first time. Chia seeds provide a viable source of functional food ingredients or nutraceuticals with protective antioxidant potential, but further research is required to confirm their anti-obesity and anti-diabetic effects.
PDF
