Antioxidant Food Research Articles

Antioxidants in functional foods

Antioxidants in functional foods

Effect of solvent type on ultrasound-assisted extraction of antioxidant compounds from Ficaria kochii: Optimization by response surface methodology

The optimization of extraction conditions to recover antioxidant rich extract from plant of Ficaria Kochii with an ultrasound-assisted system was achieved by response surface methodology. The rotatable central composite design (RCCD) was used to optimize extraction parameters in terms of total phenolic and total flavonoid content and antioxidant activity. The optimum conditions for extraction by methanol were: ratio of solvent to raw material, 10%; extraction time, 50 min and extraction temperature, 60 °C. Under these conditions, the obtained total phenolic content 46.379 mg gallic acid equivalents/g dry matter and total flavonoid content 11.754 mg quercetin equivalents/g dry matter with antioxidant property (DPPH: the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity) was 89.548%. Also, the optimum operating conditions for extraction by water were: ratio of solvent to raw material, 10%; extraction time, 30 min and extraction temperature, 40 °C. Under these conditions, the obtained total phenolic content 51.112 mg gallic acid equivalents/g dry matter and total flavonoid content 4.331 mg quercetin equivalents/g dry matter with antioxidant property was 97.004%. This study suggests that the antioxidant rich extract from plant of Ficaria Kochii can be a candidate for food antioxidant and Due to these features, this extract can be used in food storage.

Chemical Composition, Total Phenolic Content, and Antioxidant Activity of the Essential Oils Extracted from the Needle of Ten Pinus Taxa

This study investigated the chemical compositions of essential oils (EOs) from ten taxa belonging to the Pinus genus. The studied taxa that grow wildly in China, and the EOs were extracted by steam distillation; the chemical compositions were isolated and characterized by GC-MS. Eighty-one components, representing over 92.10% of the EOs, were identified. The main constituents of EOs were α-pinene (6.44%–53.00%), β-caryophyllene (2.43%–24.64%), β-pinene (0.00%–22.32%), δ-cadinene (2.56%–17.56%), germacrene D (0.74%–11.38%), and camphene (0.78%–10.48%). Furthermore, we determined the total phenolic content (TPC) of the EOs, with the values from 26.50 to 60.01 mg eq GAE/mL EO. DPPH free radical scavenging activity (DPPH), ferric reducing antioxidant power (FRAP), and ABTS radical cation scavenging activity (ABTS) were used to evaluate the antioxidant capacity of the EOs, and the obtained values were ranged from 499.15 to 1,272.75 mmol eq Trolox/mL EO, 1,255.67 to 3,857.93 mmol eq Trolox/mL EO, and 370.81 to 1,677.19 mmol eq Trolox/mL EO, respectively. The results showed that all of the EOs studied had strong antioxidant activity, and these pine plants could be used as natural antioxidants in functional food and pharmaceutical industries.

Chemical characterization of the antioxidant and α-glucosidase inhibitory active fraction of Malus transitoria leaves

Chinese Tibetan tea made from the tender leaves of Malus transitoria is a widely consumed health drink, but there are few reports on its chemical composition and biological activity. In this study, we found that a 50% ethanol extract of M. transitoria had good antioxidant and α-glucosidase inhibitory activities in vitro. Guided by in vitro bioassays, chromatographic separation and purification were conducted, and the most active fraction in M. transitoria was determined. UPLC-Orbitrap-MS/MS was used to further quickly and comprehensively characterize the chemical composition. Library searches, MS/MS fragmentation patterns of two isolated reference compounds, and bibliography were used to annotate 81 compounds, of which 2 were new compounds, and 79 were identified from M. transitoria for the first time. This study provides a scientific basis for the development of antioxidant and anti-diabetic functional foods from M. transitoria.

Nano-selenium stablilized by Konjac Glucommannan and its biological activity in vitro

Nano-selenium particles (SeNPs) are considered to have high biological activity and low toxicity, but their stability need to be improved. Konjac glucomannan (KGM) was introduced as a stabilizer for the preparation of SeNPs via ascorbic acid (AA)-sodium selenite (Na2SeO3) redox system in this study, the influence of reaction conditions on the formation of KGM-SeNPs was estimated and the preparation parameters were optimized via orthogonal experiment. It is found that KGM concentration and Se4+ concentration are the two most important parameters that affect the particle size and morphology of KGM-SeNPs, beside of the agglomeration promoted by higher temperature. The optimal product possessed spherical particles with a particle size of 50–150 nm, the selenium content in lyophilized supernatant and lyophilized precipitate were 38.17% and 19.19%, respectively, and infrared spectroscopy analysis showed KGM-SeNPs were mainly compounded by intermolecular electrostatic interaction. KGM-SeNPs exhibited inhibitory effects on Staphylococcus aureus but no on Escherichia coli and Penicillium, strong scavenging activity against ABTS•+ and DPPH•, strong reduction activity on Fe3+ and low cytotoxicity in Caco-2 cells. These results indicated that KGM-SeNPs were expected to be developed as a food-grade antioxidant or selenium supplement in food and pharmaceutical product applications.

A Review on Electrochemical Sensors and Biosensors Used in Assessing Antioxidant Activity.

Currently, there is growing interest in screening and quantifying antioxidants from biological samples in the quest for natural and effective antioxidants to combat free radical-related pathological complications. Antioxidants play an important role in human health and provide a defense against many diseases. Due to the valuable dietary role of these compounds, the analysis and determination of their amount in food is of particular importance. In recent years, many attempts have been made to provide simple, fast, and economical analytical approaches for the on-site detection and determination of antioxidant activity in food antioxidants. In this regard, electrochemical sensors and biosensors are considered promising tools for antioxidant research due to their high sensitivity, fast response time, and ease of miniaturization; thus, they are used in a variety of fields, including food analysis, drug screening, and toxicity research. Herein, we review the recent advances in sensors and biosensors for the detection of antioxidants, underlying principles, and emphasizing advantages, along with limitations regarding the ability to discriminate between the specific antioxidant or quantifying total antioxidant content. In this work, both direct and indirect methods for antioxidants detecting with electrochemical sensors and biosensors are analyzed in detail. This review aims to prove how electrochemical sensors and biosensors represent reliable alternatives to conventional methods for antioxidant analysis.

Interfacial Properties and Antioxidant Activity of Whey Protein-Phenolic Complexes: Effect of Phenolic Type and Concentration

Whey protein is a common food additive for enhancing product stability and texture, while phenolics are considered food antioxidants. As a consequence, combining whey protein with phenolics is an effective way to improve protein functionality while also maintaining polyphenol bioactivity. Herein, the functional properties and antioxidant activity of whey protein modified with various types and concentrations of oxidized phenolic compounds, including gallic acid (OGA), ferulic acid (OFA), and tannic acid (OTA), were studied. In general, the modified whey protein had a decrease in free amino content, but an increase in total phenolic content. Whey protein modified with 5% OTA showed the highest total phenolic content and the lowest free amino content. Modification of whey protein with OTA and OGA resulted in a loss of surface hydrophobicity in contrast to whey protein modified with OFA. However, no significant difference in surface activity including foam and emulsion properties in the whey protein with/without modification was observed. The modified whey protein had an increase in antioxidant activity when compared with that of the control.

Structure characterization and antioxidant activity of carboxymethylated polysaccharide from Pholiota nameko.

The objective of this paper was to prepare the carboxymethyl polysaccharide of Pholiota nameko (CPPN) and further evaluate its structural characteristics, water solubility, and antioxidant activities. The optimal carboxymethylation conditions were as follows: 20% NaOH concentration, 1.5hr alkalization, 4hr etherification time, and 60°C with 2g chloroacetic acid. Under these conditions, a substitution degree of 0.72 and a yield of 88.3% were achieved. The results of NMR and FT-IR spectra showed that carboxymethylation modification was successful. The protein, total sugar, and total phenol content decreased, while the molecular weight increased, and the monosaccharide composition content and surface structure changed upon carboxymethylation. Compared with unmodified polysaccharides, CPPN had significant antioxidant activity and water solubility. Thus, this study could provide a potential antioxidant for functional foods and pharmaceuticals. PRACTICAL APPLICATIONS: Pholiota nameko is an edible and medicinal mushroom, rich in carbohydrates, cellulose, and minerals. Pharmacological studies have shown that P. nameko polysaccharides have many medicinal effects on the human body. In this study, CPPN was synthesized by carboxymethylation of P. nameko polysaccharides. Through structural characterization, antioxidant activity, and solubility studies, carboxymethylated polysaccharides shown significant antioxidant properties and increased solubility. Therefore, this research lays the foundation for the high-value application of P. nameko polysaccharides in functional food and pharmaceutical industry.

Effect of pomegranate and orange peel extracts on the quality of fish ham under frozen storage

Aim: The objective of the present study was to evaluate the effect of pomegranate and orange peel crude extract on fish ham quality in terms of biochemical, microbiological, and sensory parameters under cold storage (-18±2oC). Methodology: The crude extracts were extracted from dry powder of orange and pomegranate peel using absolute ethanol as solvents. The extracts were standardized in the mackerel cooked meat model system to determine the concentration for the final products. Fish ham was prepared using red meat of tuna (Thunnus albacares) and white meat of bull’s eye fish (Priacanthus hamrur). The prepared fish ham was treated with 2000 mg l-1 of pomegranate and orange peel extracts and stored under frozen conditions. Results: The results obtained were compared with a control sample containing synthetic antioxidant Butylated hydroxyanisole. The results showed that pomegranate and orange peel extracts significantly (p < 0.05) reduced the lipid oxidation and microbial activity. The results of biochemical studies revealed that there was a considerable increase in the quality parameter in all treated samples. The fish ham treated with pomegranate peel extract, orange peel extracts showed formation slower primary, secondary oxidation products and breakdown of nitrogenous compounds. Interpretation: Pomegranate and orange peel can be a substitute for synthetic antioxidants. These findings suggest that the pomegranate and orange peel serve as a choice to use as a food antioxidant for extending the shelf life of fish fishery products.

Structural Elucidation and Antioxidant Activities of a Neutral Polysaccharide From Arecanut (Areca catechu L.).

A novel neutral polysaccharide designated as PAP1b was isolated from Areca catechu L. by hot water extraction, ethanol precipitation, and column chromatography. PAP1b was mainly composed of mannose, galactose, xylose, and arabinose in a ratio of 4.1:3.3:0.9:1.7, with an average molecular weight of 37.3 kDa. Structural characterization indicated that the backbone of PAP1b appeared to be composed mainly of → 6-β-Manp-(1 →, → 4)-α-Galp-(1 → and → 3,6)-β-Manp-(1 →) residues with some branches, and terminal of (1 →)-linked-β-Manp residues. The results of bioactivity experiments showed that PAP1b had antioxidant in vitro, esspecially on scavenging DPPH and hydroxyl radicals. Therefore, the polysaccharide from Areca catechu L. could be used as a potential antioxidant in functional food.

Gelatin-Based Biofilms with FexOy-NPs Incorporated for Antioxidant and Antimicrobial Applications

Currently, gelatin-based films are regarded as promising alternatives to non-environmentally friendly plastic films for food packaging. Nevertheless, although they have great biodegradability, their weak mechanical properties and high solubility limit their applications. In this way, the use of nanoparticles, such as FexOy-NPs, could improve the properties of gelatin-based biofilms. Thus, the main objective of this work was to include different concentrations of FexOy-NPs (0.25 and 1.0%) manufactured by green synthesis (GS) and chemical synthesis (CS) into gelatin-based biofilms in order to improve their properties. The results show that FexOy-NPs can be distributed throughout the biofilm, although with a greater concentration on the upper surface. In addition, the incorporation of FexOy-NPs into the biofilms improves their physicochemical, mechanical, morphological, and biological properties. Thus, it is possible to achieve suitable gelatin-based biofilms, which can be used in several applications, such as functional packaging in the food industry, antioxidant and antimicrobial additives in biomedical and pharmaceutical biomaterials, and in agricultural pesticides.

Preparation, structural characterization and antioxidant activity of water-soluble polysaccharides and purified fractions from blackened jujube by an activity-oriented approach

This study aimed to investigate the structural features and antioxidant activity in vitro of crude blackened jujube polysaccharides (BJPs) and five purified polysaccharides based on the activity-oriented approach. The crude BJPs exhibited dose-dependent radical scavenging activity and total reducing capacity, and provided excellent protective effects against H2O2-damaged HUVECs via up-regulating mitochondrial membrane potential and down-regulating intracellular reactive oxygen species. After fractionation by column chromatography, the five purified components differed in chemical composition, molecular weight, monosaccharide composition (type and relative proportion) and FTIR band (peak pattern or intensity, especially in the range of 1000.0–1200.0 cm−1), as well as protective effects against H2O2-induced HUVECs. As the most abundant and potent antioxidant component, the backbone of BJP-3 was mainly composed of →4)-α-l-GalpA (1→, →5)-α-l-Araf (1→ residues with two terminals of T-α-l-Araf (1→ and T-β-d-Galp (1→. The above results compared the structural and bioactive properties of different blackened jujube polysaccharides and highlighted their potential as antioxidants for functional foods.

Integrative analysis of transcriptomics and metabolomics to reveal the melanogenesis pathway of muscle and related meat characters in Wuliangshan black-boned chickens

BackgroundMelanin is an important antioxidant in food and has been used in medicine and cosmetology. Chicken meat with high melanin content from black-boned chickens have been considered a high nutritious food with potential medicinal properties. The molecular mechanism of melanogenesis of skeletal muscle in black-boned chickens remain poorly understood. This study investigated the biological gene-metabolite associations regulating the muscle melanogenesis pathways in Wuliangshan black-boned chickens with two normal boned chicken breeds as control.ResultsWe identified 25 differentially expressed genes and 11 transcription factors in the melanogenesis pathways. High levels of the meat flavor compounds inosine monophosphate, hypoxanthine, lysophospholipid, hydroxyoctadecadienoic acid, and nicotinamide mononucleotide were found in Wuliangshan black-boned chickens.ConclusionIntegrative analysis of transcriptomics and metabolomics revealed the dual physiological functions of the PDZK1 gene, involved in pigmentation and/or melanogenesis and regulating the phospholipid signaling processes in muscle of black boned chickens.

Physicochemical properties and in vitro digestion behavior of a new bioactive Tremella fuciformis gum

A new easy-dissolved Tremella fuciformis gum (TFG) from fruiting body was investigated in detail from three aspects: physicochemical characteristics, rheological behavior and in vitro digestion behavior. The results showed that TFG consisted of 73.9% polysaccharides, exhibiting easy solubility in water and good colloidal characteristics and stability. The physical and chemical treatments could decrease the apparent viscosity of TFG solution. The antioxidation activity of TFG remained constant at each static in vitro digestion phase, revealing that this gum could be used as a potential food thickener and antioxidant. The digestion behavior of TFG was also determined using a dynamic in vitro digestive system, DIVRS-II. The results demonstrated that the digestion behavior of TFG should be attributed to the morphology of digestive tracts, continuous secreting and continuous emptying. The antitussive effect of TFG was related to the increase in serum IL-10 content.

Functional edible films/coatings integrated with lactoperoxidase and lysozyme and their application in food preservation

Concerning environmental pollution caused by plastic-based food packaging materials and the demand for healthy and safe food, the development of edible food packaging films/coatings with antimicrobial properties is urgently required. Lactoperoxidase (LP) and lysozyme (LY), biopreservation enzymes commonly used in the food industry, appear to be excellent choices for incorporating edible films/coatings to improve food preservation capabilities. In this review, the results of recently published studies on the functional properties and applications of edible films/coatings containing LP and LY are comprehensively reviewed. Several commonly used biomacromolecules have been discussed, such as chitosan, alginate, whey protein, and gelatin, used to prepare edible films/coatings integrated with LP and LY. The application of biopolymer-based films/coatings containing LP and LY to various food packaging was also discussed. Because LP and LY are safe, stable, and have strong antimicrobial properties, and are compatible with most biological macromolecules, the edible films/coatings integrated with LP and LY are suitable for preserving various foods such as fresh fruit, poultry, and seafood products. In addition, the use of edible films/coatings integrated with LY and LP in combination with other food preservation methods or antioxidants in food preservation applications is expected to have the more significant positive effect than single addition.

Physicochemical property and antioxidant activity of polysaccharide from the seed cakes of Camellia oleifera Abel.

Seed cake refers to the food by‐product of Camellia oleifera Abel, and its insufficient utilization can cause serious environment pollution and resource waste. This study aimed to investigate antioxidant activities of the polysaccharide from the seed cakes of Camellia oleifera Abel (COCP) in vitro and in vivo. The physicochemical property of COCP was also determined. COCP was characterized to be an acidic glycoprotein and mainly consisted of rhamnose (Rha), arabinose (Ara), galactose (Gal), glucose (Glc), xylose (Xyl), mannose (Man), and galacturonic acid (Gal‐UA). COCP exhibited the polysaccharide's characteristic absorption in the Fourier transform infrared (FT‐IR) spectroscopy and showed as sheet‐like structures with a smooth surface under the scanning electron microscope (SEM). COCP exerted good scavenging activities on ABTS, DPPH, and OH radicals, with IC50 values of 2.94, 2.24, and 5.09 mg/ml, respectively. COCP treatment improved learning and memory abilities of D‐galactose‐induced aging mice. Significant decreases were found in the levels of alanine transaminase (ALT), aspartate aminotransferase (AST), creatinine (CRE), blood urea nitrogen (BUN), creatine kinase (CK), and lactate dehydrogenase (LDH) in serum, as aging mice were supplemented with COCP. Aging mice showed obviously higher malondialdehyde (MDA) contents and lower superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px) activities in serum, brain, liver, kidney, and heart. The phenomena were noticeably reversed when mice were treated with COCP. Results indicated that COCP exerted excellent antioxidant activities in vitro and in vivo, which support its potential application as a natural antioxidant in food and medicine industries.

Study of Rapid HPLC Method for the Determination of Antioxidants in Foods, and Standard Solution Stability during Storage

In this study, we simultaneously determined three antioxidants, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and tert-butylhydroquinone (TBHQ), using HPLC equipped both with a photodiode array detector and a fluorescence detector in 25 minutes per sample. Due to the combined use of the two detectors, we could achieve improved target selectivity. Further, quantification at the specific wavelengths for each target substance particularly increased BHT detection sensitivity. This approach enabled us to avoid repeated measurements during daily inspections. Furthermore, detections were performed using LC-MS/MS instead of GC-MS to overcome the problem of helium gas shortage.In addition, we investigated antioxidant stability in standard solutions during storage. Although TBHQ was stable in methanol with ascorbic acid at -20℃, ascorbic acid storage has possibility to lead to decrease in BHT and BHA concentrations. We recognized that the mixture of BHT and BHA dissolved in methanol at 4℃ and that of BHT, BHA and TBHQ dissolved in methanol with ascorbic acid at -20℃ were suitable for about one year.

Chemical composition, structural properties, rheological behavior and functionality of Melissa officinalis seed gum

In the present work, the chemical composition, structural properties, rheological behavior and biological activity of a novel polysaccharide extracted from Melissa officinalis seeds were examined. Melissa officinalis seed gum (MOSG) is mainly composed of galactose and mannose. The weight average molecular weight of MOSG was found to be 1.36 × 107 g/mol. The zeta potential of MOSG was −44.26 ± 0.67 mV (at pH = 7). A time-dependent and strong shear-thinning behavior was observed for MOSG dispersions at different concentrations (0.5, 1 and 1.5% (w/w)). The intrinsic viscosity of MOSG was 3.45 dL/g. MOSG could effectively scavenge free radicals with certain dose-effect relationships. MOSG can be employed as gelling agent, stabilizer and antioxidant in food, cosmetic and pharmaceutical systems.

The effects of thymoquinone and quercetin on the toxicity of acrylamide in rat glioma cells.

Acrylamide is a neurotoxic agent forming in foods. Thymoquinone and quercetin are plant-derived antioxidants in various foods with known benefits. C6 cells are glioblastoma cells. In this study, we aimed at preventing acrylamide toxicity by thymoquinone and quercetin in the C6 cell line. In our study, first, toxic doses of acrylamide, nontoxic doses of thymoquinone and quercetin in C6 cells for 24 h were determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) colorimetric test. After that, caspase 3/7 and annexin V tests were performed by flow cytometry to evaluate whether the apoptosis pathway was inducted. Furthermore, autophagy and oxidative stress were assessed by flow cytometry. The amount of Nrf2 (nuclear factor erythroid 2-related factor 2) was determined by immunocytochemistry. The morphological examination was performed by microscopic analyses. As a result, 4 mM of acrylamide was determined to be used to induce toxicity in C6 cells. The nontoxic doses of thymoquinone and quercetin were respectively determined as 3.9 and 2.0 µM. Thymoquinone and quercetin not only reduced acrylamide-induced apoptosis in annexin V and caspase 3/7 assays but also morphological deformations in microscopic examinations. In autophagy, it was revealed that acrylamide-induced autophagy was decreased by quercetin and thymoquinone pretreatments. As for Nrf2 expression, it was observed that acrylamide increased Nrf2 expression, and thymoquinone and quercetin pretreatments increased it even further. In conclusion, in the study, acrylamide demonstrated a damaging effect on C6 glioblastoma cells, and thymoquinone and quercetin pretreatments exerted a protective effect against acrylamide-induced damage in C6 cells.

NRF2 Activation in Autophagy Defects Suppresses a Pharmacological Transactivation of the Nuclear Receptor FXR.

NF-E2-related factor 2 (NRF2), an antioxidant transcription factor, is activated in autophagy-deficient mice due to the accumulations of p62/SQSTM1 and its subsequent interaction with Kelch-like-ECH-associated protein 1 (KEAP1), an adaptor component for Cullin3-based E3 ubiquitin ligase complex. Farnesoid x receptor (FXR/NR1H4) is a ligand-dependent transcription factor that belongs to the nuclear receptor superfamily. FXR plays an essential role in bile acid synthesis and enterohepatic circulation, affecting glucose and lipid metabolism. Obeticholic acid as a potent FXR agonist has been approved to treat primary biliary cholangitis and clinical trials for its use in the treatment of other liver diseases are underway. Here we show that NRF2 activation in autophagy defects impedes a transactivation of FXR. Liver-specific Atg7 knockout mice or a treatment of autophagy inhibitor showed decreased inductions of FXR target genes upon its synthetic agonists. Moreover, enforced NRF2 activations with small molecules potently decreased the pharmacological activation of FXR in cultured cells. Finally, we demonstrate that NRF2 activation by the treatment with the food antioxidant butylated hydroxyanisole is necessary and sufficient to inhibit the pharmacological activation of FXR in vivo. These results reveal a novel function of the basal autophagy-NRF2 axis for the regulation of FXR transactivation, and shed light on a potential therapeutic strategy in metabolic disease.