Antioxidant Food Research Articles

Evaluation of Antioxidant Activities from a Sustainable Source of Okara Protein Hydrolysate Using Enzymatic Reaction

Okara is a solid byproduct created during the processing of soy milk. The production of protein hydrolysates utilizing enzymatic tests such as papain can result in the production of bioactive peptides (BPs), which are amino acid sequences that can also be produced from the okara protein by hydrolysis. The objective of this study was to investigate the antioxidant activities of okara hydrolysates using papain, based on the in silico and in vitro assays using the papain enzyme. We found that using the in silico assessment, the antioxidant peptides can be found from the precursor (glycinin and conglycinin) in okara. When used as a protease, papain provides the maximum degree of hydrolysis for antioxidative peptides. The highest-peptide-rank peptide sequence was predicted using peptide ranks such as proline–histidine–phenylalanine (PHF), alanine–aspartic acid–phenylalanine (ADF), tyrosine–tyrosine–leucine (YYL), proline–histidine–histidine (PHH), isoleucine–arginine (IR), and serine–valine–leucine (SVL). Molecular docking studies revealed that all peptides generated from the parent protein impeded substrate access to the active site of xanthine oxidase (XO). They have antioxidative properties and are employed in the in silico approach to the XO enzyme. We also use papain to evaluate the antioxidant activity by using in vitro tests for protein hydrolysate following proteolysis. The antioxidant properties of okara protein hydrolysates have been shown in vitro, utilizing DPPH and FRAP experiments. This study suggests that okara hydrolysates generated by papain can be employed as natural antioxidants in food and for further applications, such as active ingredients for antioxidants in packaging.

Impact of Processing Method and Storage Time on Phytochemical Concentrations in an Antioxidant-Rich Food Mixture.

Foods high in phytochemicals are known for their role in the prevention of chronic disease development, but after processing and storage, such food products may lose part of their functionality as these compounds are sensitive to the impact of processing temperature and the type of methods applied. Therefore, we measured the levels of vitamin C, anthocyanins, carotenoids, catechins, chlorogenic acid, and sulforaphane in a complex blend of fruits and vegetables, and when applied to a dry food product, after exposure to different processing methods. These levels were compared between pasteurized, pascalized (high-pressure processing), and untreated conditions. Furthermore, we established the effect of freezing and storage time on the stability of these compounds. The results showed that pascalization better preserved vitamin C and sulforaphane, whereas pasteurization resulted in higher concentrations of chlorogenic acid, carotenoids, and catechins. For samples which were frozen and thawed immediately after processing, pascalization was the optimal treatment for higher contents of lutein, cyanidin-3-glucoside, quercetin-3-glucoside, delphinidin-3-glucoside, peonidin-3-glucoside, and epicatechin gallate. Ultimately, the optimal processing method to preserve phytochemicals in fruit and vegetable products is as complex as the blend of compounds, and this decision-making would best be led by the prioritized nutrient aim of an antioxidant food product.

Optimisation of ultrasonic-assisted extraction and biological activity of total flavonoids from leaves of Murrayae exotica using response surface methodology

ABSTRACT Murrayae exotica is a traditional Chinese medicine widely grown in southeast China. A Box–Behnken design of response surface methodology was employed to further optimise ultrasonic-assisted extraction conditions for M. exotica leaves total flavonoids (MELTF). The results showed that the optimised extraction conditions were an ultrasonic power of 240 W, an ultrasonic temperature of 60 °C, a solvent concentration of 76%, an ultrasonic time of 55 min and a liquid–solid ratio of 22 mL · g−1. Under these conditions, 8.59 ± 0.34 mg · g−1 was achieved as the mean experimental value of extraction yield, which amounts to 2.56 times that of ethanol leaching extraction. As compared to MELTF, MELTF after purification (MELPTF) had a higher purity of 9.96%, which was nearly nine times higher than that of MELTF (1.26%). As compared to MELTF, MELPTF had higher α-glucosidase and α-amylase inhibitory activities as well as DPPH· and ABTS·+ scavenging activities with IC50 values of 0.021, 0.094, 0.245 and 0.113 mg · mL−1, which are 1.33, 2.12, 3.17 and 1.78 times higher than those of MELTF (0.028, 0.199, 0.777 and 0.201 mg · mL−1). The study thus demonstrates the eligibility of MELPTF to be considered as a multifunctional bioactive ingredient having potential applications in anti-hyperglycaemic pharmaceutical formulation and as an antioxidant in functional foods.

Development and characterization of sustainable-active-edible-bio based films from orange and pomegranate peel waste for food packaging: Effects of particle size and acid/plasticizer concentrations

Sustainable packaging materials especially from food processing waste are of getting interest. The aim of the study was to develop edible bio based films from processing wastes of pomegranate and orange peels. For this purpose, pomegranate and orange peels were dried and processed into flour in different particle sizes. The effects of particle size, concentration of acid and plasticizer on physical and mechanical properties were investigated. Antimicrobial, antioxidant, morphological and thermal properties were further determined for the selected film formulations. Results showed that the particle size significantly affected mechanical properties of the films (p ≤ 0.05), with improvement of the mechanical properties for the reduced particle size. Pomegranate and orange peel based films showed very high antimicrobial activity against E. coli and S. aureus irrespective of particle sizes. The pomegranate and orange peel based films had homogeneous, smooth, and crack-free surfaces. Pomegranate and orange peel based films showed very similar thermal properties and major thermal degradation was observed between 160 and 300 °C for both type of films irrespective of particle sizes. Pomegranate and orange peels could be good potential as antioxidant and antimicrobial biopolymer sources for sustainable and active food coating/packaging.

Antioxidant Activity and Phytochemicals of Locally Consumed Plant Foods from Baguio City, Philippines

In the Philippines, Baguio City – known as the “City of Pines” – holds the country’s major source of temperate climate vegetables. With increased dietary awareness, the consumption of plant foods rich in antioxidants has become relevant. Twenty-nine methanolic extracts from Baguio-produced plant foods were evaluated for antioxidant potential using DPPH, ferric reduction antioxidant power (FRAP), metal chelation, superoxide anion, nitric oxide, hydroxyl radical scavenging activities, MTT reduction, and phytochemical tests. Fagopyrum tataricum leaves, Vaccinium myrtoides fruit, and Morus alba fruit showed the most effective DPP radical, concentration-dependent reducing power, but low metal chelating activity. Solanum tuberosum tuber (22.86±63.26%) showed effective concentration-dependent chelating activity at 125 μg/mL. Citrus aurantium fruit (26.77±9.24%) and Raphanus raphanistrum root (41.13±0.11%) demonstrated an effective scavenging activity against superoxide anions at 45.5 μg/mL. Significant nitric oxide scavenging activity was observed in some fruits. Brassica oleracea Cab leaves (54.36 ± 2.38%) showed the highest inhibitory activity against hydroxyl radicals at 166.7 μg/mL. Phytochemical analyses showed that most plant samples revealed the presence of glycosides, terpenes/terpenoids, and steroids/phytosterols, while few contained phenolic and tannin components. These phytochemicals may explain the dual behavior as an antioxidant or a prooxidant observed. Thus, determining food antioxidant component types and their concentration is necessary to maximize the potential to scavenge oxidants.

Changes in Phytochemical Content, Antioxidant Activity, and Anti-Inflammatory Properties of Cudrania tricuspidata Fruits Treated by Roasting.

The study investigated the antioxidant effects of roasted Cudrania tricuspidata (C. tricuspidata) fruits by comparing them with unroasted C. tricuspidata fruits. The results showed that the roasted C. tricuspidata fruits (150 °C, 120 min) exhibited significantly higher antioxidant activity, especially in terms of anti-inflammatory effects, than the unroasted fruits. Interestingly, there is a high correlation between the color of the roasted fruit and the antioxidant activity. Heating disrupts cells and deactivates endogenous oxidative enzymes, leading to an increase in flavonoid content. Moreover, heat treatment may also interfere with plant metabolism, thereby influencing flavonoid content. Moreover, an HPLC analysis of roasted fruits in our study showed that the increase in antioxidant activity was attributed to the increase in flavan-3-ols and phenolic acids in the roasted C. tricuspidata fruits. To the best of our knowledge, this is the first time the antioxidant activity and anti-inflammation of roasted C. tricuspidata fruits was studied. The study concluded that roasted C. tricuspidata fruits could be a valuable natural source of antioxidants for various food and medicinal applications.

Lactic acid bacteria with a strong antioxidant function isolated from "Jiangshui," pickles, and feces.

Excessive free radicals and iron death lead to oxidative damage, which is one of the main causes of aging and diseases. In this field of antioxidation, developing new, safe, and efficient antioxidants is the main research focus. Lactic acid bacteria (LAB) are natural antioxidants with good antioxidant activity and can regulate gastrointestinal microecological balance and immunity. In this study, 15 LAB strains from fermented foods ("Jiangshui" and pickles) or feces were evaluated in terms of their antioxidant attributes. Strains with strong antioxidant capacity were preliminarily screened by the following tests: 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical, superoxide anion radical scavenging capacity; ferrous ion chelating assay; hydrogen peroxide tolerance capacity. Then, the adhesion of the screened strains to the intestinal tract was examined using hydrophobic and auto-aggregation tests. The safety of the strains was analyzed based on their minimum inhibitory concentration and hemolysis, and 16S rRNA was used for molecular biological identification. Antimicrobial activity tests showed them probiotic function. The cell-free supernatant of selected strains were used to explore the protective effect against oxidative damage cells. The scavenging rate of DPPH, hydroxyl radicals, and ferrous ion-chelating of 15 strains ranged from 28.81-82.75%, 6.54-68.52%, and 9.46-17.92%, respectively, the scavenging superoxide anion scavenging activity all exceeded 10%. According to all the antioxidant-related tests, strains possessing high antioxidant activities J2-4, J2-5, J2-9, YP-1, and W-4 were screened, these five strains demonstrated tolerance to 2 mM hydrogen peroxide. J2-4, J2-5, and J2-9 were Lactobacillus fermentans and γ-hemolytic (non-hemolytic). YP-1 and W-4 were Lactobacillus paracasei and α-hemolytic (grass-green hemolytic). Although L. paracasei has been proven as a safe probiotic without hemolytic characteristics, the hemolytic characteristics of YP-1 and W-4 should be further studied. Due to the weak hydrophobicity and antimicrobial activity of J2-4, finally, we selected J2-5, J2-9 for cell experiment, J2-5 and J2-9 showed an excellent ability that resistant to oxidative damage by increasing SOD, CAT, T-AOC activity of 293T cells. Therefore, J2-5, and J2-9 strains from fermented foods "Jiangshui" could be used as potential antioxidants for functional food, health care, and skincare.

Novel Dual-Emission Carbonized Polymer Dot-Based Ratiometric Fluorescence Probe for the Sensitive Detection of Tertiary Butylhydroquinone.

Tertiary butylhydroquinone (TBHQ), one of the most common antioxidants in many foods, has attracted widespread attention due to its potential risk to human health. In this work, an "on-off-on" ratiometric fluorescent probe was prepared using dual-emission carbonized polymer dots (d-CPDs), which can be used to detect TBHQ in edible oils. The ratiometric fluorescent sensing system consisted of blue fluorescent CPDs (b-CPDs) as the response signal and yellow fluorescent CPDs (y-CPDs) as the internal reference material. The blue fluorescence of b-CPDs was gradually quenched with increasing Fe3+ ion concentration, while the yellow fluorescence was essentially unaffected. Interestingly, TBHQ can restore the fluorescence intensity of b-CPDs. Meanwhile, the fluorescence mechanism of Fe3+ on b-CPDs was investigated by density functional theory, both after the addition of TBHQ, and CPDs were released and their fluorescence was restored due to the competitive reaction of TBHQ-Fe3+. Thus, the d-CPDs probe was able to detect Fe3+ accurately in an "on-off" manner and thus TBHQ in an "off-on" manner. At an optimal Fe3+ concentration, the ratiometric sensing system provided fine linearities for determining TBHQ in the range from 0.2 to 2 μM and an ingenious detection limit of 0.052 μM. The CPDs ratiometric fluorescent probe designed in this work may have a broader application in the rapid, susceptive, and low-cost determination of TBHQ in various foods.

Antioxidant Activity Test of Scrubbing Cream of Coffee (Coffea Arabica L.) Grounds Ethanol Extract Origin in Wamena, Papua

Background: Coffee grounds are residue from coffee powder that has been brewed. Coffee grounds contain substances that can act as antioxidants such as flavonoids and polyphenols. Objective: This study was to evaluate the physical quality of l scrubbing cream and to test the antioxidant activity of coffee powder extract in scrubbing cream. Methods: The scrubbing cream was made in three Formulas with an extract concentration of 0.05% (F1); 0.1% (F2); 0.5% (F3); positive control was vitamin C, and negative control was scrub base, and then each formula was repeated three times. Evaluation of physical preparation quality included organoleptic test, homogeneity, pH, spreading, and adherence. The antioxidant activity test was done using the DPPH method. Results: Based on the results of the physical quality test and antioxidant activity tests, showed that the three formulas by evaluating the organoleptic, homogeneity, pH, spreading, and adherence of the scrubbing cream preparations qualified the requirements for the semisolid preparation. Effects of antioxidant test shown by IC50 values of negative control, F1, F2, F3, and vitamin C respectively were 230.63 ppm, 172.90 ppm, 112.73 ppm, 84.93 ppm, and 6.74 ppm. Conclusion: F3 (0.5%) has antioxidant activities which are classified in the strong category with an IC50 value of 84.93 ppm. So that through this research it can be said that coffee grounds have the potential as antioxidants in food and cosmetic products.

Colorimetric sensor array based on Au2Pt nanozymes for antioxidant nutrition quality evaluation in food

Total antioxidant capacity (TAC) has become an important index to evaluate the food quality. Effective antioxidant detection has been the research hotspot of scientists. In this work, a novel three-channel colorimetric sensor array founded on Au2Pt bimetallic nanozymes for the discrimination of antioxidants in food was constructed. Benefiting from the unique bimetallic doping structure, Au2Pt nanospheres exhibited the excellent peroxidase-like activity with Km of 0.044 mM and Vmax of 19.37 × 10−8 M s−1 toward TMB. The density functional theory (DFT) calculation revealed that Pt atom in the doping system was active sites and there was no energy barrier in catalytic reaction which made Au2Pt nanospheres had excellent catalytic activity. Accordingly, a multifunctional colorimetric sensor array was constructed based on Au2Pt bimetallic nanozymes for rapid and sensitive detection of five antioxidants. Based on the different reduction ability of antioxidants, oxidized TMB could be reduced in different degrees. In the presence of H2O2, the colorimetric sensor array could generate differential colorimetric signals (fingerprints) by using TMB as the chromogenic substrate, which could be accurately discriminated through linear discriminant analysis (LDA) with a detection limit of <0.2 μM. The sensor array was able to the evaluate TAC in three actual samples (milk, green tea and orange juice). Furthermore, we prepared a rapid detection strip to meet the needs of practical application, making a positive contribution to food quality evaluation.

Development of chicken tender pops by utilizing pomegranate peel powder.

Pomegranate peel powder (PPP) is a rich source of many bioactive components particularly polyphenols that are interlinked to various technological and functional properties. In the present study, chicken tender pops were developed with incorporation of PPP, and its effect on quality attributes and storage stability of the product were evaluated. The treatments were formulated using 0%, 3%, 6%, and 9% PPP in replacement of chicken. The physicochemical properties, texture profile, instrumental color, sensory attributes, and storage stability were assessed for 21 days at refrigeration temperature, at a regular interval of 7 days. The results indicated that the inclusion of PPP significantly (p < .05) increased the dietary fiber from 0.25% in T0 to 1.45% in T3 at Day 0 and WHC 43.60% ± 0.02 in T0 to 49.36% ± 0.02 in T3 at Day 0, whereas the moisture content significantly reduced from 60.05% ± 0.03 in T0 to 55.08% ± 0.01 in T3 at the start of the study. In addition, the values of TBARS were significantly (p < .05) reduced for treated samples 0.72 mg MDA/Kg in T3 as compared to control 1.17 mg MDA/Kg on the 21st day of storage, whereas a significant increase (p < .05) in TPC from 0.90 mg GAE/g to 3.87 mg GAE/g in T0 to T3 was observed at the start of the study. For TPA, a significant (p < .05) increase was noticed in hardness, chewiness, and gumminess, whereas cohesiveness and springiness showed a non-significant (p > .05) change in treated samples in relation to control, and the instrumental color (L* and a*) decreased significantly. However, pH, crude fiber, fat, ash, and protein content showed non-significant (p > .05) variations over time. The sensory evaluation suggested that chicken tender pops supplemented with 6% PPP (T2) presented high overall acceptability and balanced organoleptic properties. Hence, it can be concluded that PPP can be effectively utilized as a natural fiber source, antioxidant, and antimicrobial agent in novel functional foods.

Reverse microemulsions as nano-carriers of tea polyphenols retard oxidation of Eucommia ulmoides oliver seed oil

Eucommia ulmoides Oliver seed oil, rich in polyunsaturated fatty acids (PUFAs), is susceptible to lipid oxidation in foods. Tea polyphenols (TPs) may effectively retard lipid oxidation in non-polar systems according to the polar paradox theory. In this study, we constructed a TPs-loaded water-in oil (W/O) microemulsion, which is a transparent, spontaneously formed, and thermodynamically stable colloidal system. This system consisted of E. ulmoides oil (38%, w/w), Span80, Tween 80, 1,2 propanediol, water, and TPs (3%, w/w). TPs were encapsulated in water cores of microemulsion, endowing this system with the higher oxidative stability and radical scavenging abilities. The accelerated oxidation assay demonstrated that low-dose TPs (<0.5%, w/w) were more effective in retarding lipid oxidation than that of high-dose TPs. Within 56 d, the peroxide value of TPs-loaded microemulsion increased to 16.479 meq/kg oil at 65 ℃ and that of E. ulmoides oil exceeded the Food Safety standards value within only 45 d. These findings indicate that TPs encapsulated into microemulsion effectively inhibit PUFA-rich oil oxidation. The nano-scale W/O dispersed system favors the protection and practical application of natural water-soluble antioxidants in PUFAs-rich lipid foods.

Effect of neutralization treatment on properties of chitosan/bamboo leaf flavonoids/nano-metal oxide composite films and application of films in antioxidation of rapeseed oil

Neutralization treatment improved the slow-release antioxidant food packaging function of chitosan (CS)/bamboo leaf flavone (BLF)/nano-metal oxides composite films. The film cast from the CS composite solution neutralized by KOH solution had good thermal stability. The elongation at break of the neutralized CS/BLF film was increased by about 5 times, which provided the possibility for its packaging application. After 24 h of soaking in different pH solutions, the unneutralized films swelled severely and even dissolved, while the neutralized films maintained the basic structure with a small degree of swelling, and the release trend of BLF conformed to the logistic function (R2 ≥ 0.9186). The films had a good ability to resist free radicals, which was related to the release amount of BLF and the pH of the solution. The antimicrobial neutralized CS/BLF/nano-ZnO film, like the nano-CuO and Fe3O4 films, were effective in inhibiting the increase in peroxide value and 2-thiobarbituric acid induced by thermal oxygen oxidation of rapeseed oil and had no toxicity to normal human gastric epithelial cells. Therefore, the neutralized CS/BLF/nano-ZnO film is likely to become an active food packaging material for oil-packed food, which can prolong the shelf life of packaged food.

Antioxidant Potential and Phenolic Acid Profiles in Triticale Grain under Integrated and Conventional Cropping Systems

Cereals are a valuable source of biologically active compounds. Phenolic compounds, of which the phenolic acids (PA) found in cereal grains constitute a significant proportion, are characterized by health-promoting properties largely due to their antioxidant capacity. PA, located mainly in the outer parts of the grain, play an important role in preventing environmental stresses. Triticale is a cereal species of increasing economic value, and also value for human consumption. The aim of this study was to demonstrate the effect of conventional (CONV) and integrated (INTEG) cropping systems on antioxidant activity and content of selected PA in triticale cultivars (Meloman, Panteon, Belcanto) grain. The experiment was conducted in seasons from 2019/2020 to 2021/2022. Among the PA tested, ferulic acid (FER) had the highest contribution to total PA content (TPAs), with 519, 99, and 1115 μg g−1 in whole grain, flour, and bran, respectively. The unfavorable hydrothermal conditions occurring in the seasons (rainfall deficit) increased TPA, mainly in whole grain. Grain cv. Meloman had the highest PA content in whole grain, flour, and bran and cv. Belcanto had the lowest, with differences of 22.7, 18.2, and 15.7% respectively. Cultivation of triticale under the CONV vs. INTEG cropping system resulted in reduced amounts of TPAs in flour and bran and PA: p-hydroxybenzoic acid (p-HB) in flour, syringic acid (SYR) in whole grain and bran, and ferulic acid (FER) and sinapic acid (SIN) in bran. The CONV cropping system also caused a decrease in antioxidant activity (AOA) in flour and bran. In most of the cases analyzed, the highest antioxidant activity and content of PA were found in bran, and the lowest were found in flour. The high presence of PA in triticale grain indicates that this cereal, especially when grown under the INTEG cropping system, can be destined for consumption and provide a source of valuable antioxidants for various food and nutraceutical purposes.

The link between the phenolic composition and the antioxidant activity in different small berries: A metabolomic approach

Small berries have become an attractive topic of research due to their high content in phenolic compounds and reported antioxidant activity. However, there are currently few reports on the deep characterization of their polyphenol composition. Five kinds of berries (raspberry, blackberry, blueberry, mulberry and black chokeberry) were studied to compare the antioxidant activities and polyphenol compositions of both berry juice and pomace (by-products in processing). Results showed that pomaces were more potent antioxidants than juices, especially those that originated from red raspberry. The polyphenol contents in pomaces ranged from 137 to 222 mg/g, this was higher than juices that ranged from 2.75 to 8.88 mg/g, with mulberry accounting for the highest content. The main compounds in pomaces were phenolic compounds with different relative contents found by UPLC-MS/MS. A total of 568 compounds were identified, including 238 flavonoids and 131 phenolic acids. PCA, HCA and OPLS-DA analyses were performed to find similarities on the polyphenol and metabolomic profile of the sampled berries. This analysis unveiled that all studied berries presented a significantly different polyphenol profile, on which raspberry and blackberry were the most similar. Results suggested that berry pomaces can be valuable sources of phenolic compounds of which the major components are anthocyanins and phenolic acids, with potential applications as antioxidant food additives, or raw materials for pharmaceuticals, nutraceuticals, and cosmetics.

Evaluation of the Biological Properties of an Optimized Extract of Polygonum cuspidatum Using Ultrasonic-Assisted Extraction.

Phytochemicals are natural compounds found in plants that have potential health benefits such as antioxidants, anti-inflammatory and anti-cancer properties, and immune reinforcement. Polygonum cuspidatum Sieb. et Zucc. is a source rich in resveratrol, traditionally consumed as an infusion. In this study, P. cuspidatum root extraction conditions were optimized to increase antioxidant capacity (DPPH, ABTS+), extraction yield, resveratrol concentration, and total polyphenolic compounds (TPC) via ultrasonic-assisted extraction using a Box-Behnken design (BBD). The biological activities of the optimized extract and the infusion were compared. The optimized extract was obtained using a solvent/root powder ratio of 4, 60% ethanol concentration, and 60% ultrasonic power. The optimized extract showed higher biological activities than the infusion. The optimized extract contained 16.6 mg mL-1 resveratrol, high antioxidant activities (135.1 µg TE mL-1 for DPPH, and 230.4 µg TE mL-1 for ABTS+), TPC (33.2 mg GAE mL-1), and extraction yield of 12.4%. The EC50 value (effective concentration 50) of the optimized extract was 0.194 µg mL-1, which revealed high cytotoxic activity against the Caco-2 cell line. The optimized extract could be used to develop functional beverages with high antioxidant capacity, antioxidants for edible oils, functional foods, and cosmetics.

Ultrasonic-assisted extraction, characteristics and activity of Ipomoea batatas polysaccharide

Ipomoea batatas polysaccharides (IBPs) have many important physiological functions. The optimal extraction conditions were extraction time of 40 min, solid–liquid ratio of 1:8 and ultrasonic power of 240 W. 1D/2D nuclear magnetic resonance (1D/2D NMR) analysis showed that the main chain of IBP-1A was mainly composed of →4)-α-D-Glcp-(1→ and →3, 6)-β-D-Glcp-(1→ residues. In vivo experiments showed that polysaccharide significantly increased the levels of antioxidation-related enzymes and metabolites in older mice. It could significantly relieve oxidative stress injury and delay aging. Therefore, this study provided a new theoretical basis for the development of IBPs as antioxidant food.

Silica nanoparticles loaded with caffeic acid to optimize the performance of cassava starch/sodium carboxymethyl cellulose film for meat packaging

Cassava starch/sodium carboxymethyl cellulose (CC) was used as the substrate to create a multipurpose food packaging film, and caffeic acid@silica nanoparticles (C@SNPs) was added. The encapsulation rate of caffeic acid in C@SNPs was 84.7 ± 0.97 %. According to SEM pictures, the nanoparticles were evenly dispersed throughout the film and exhibited good compatibility with the other polymers. C@SNPs was added, which enhanced the physical characteristics of film and decreased its water solubility. The best mechanical and oxygen barrier qualities among them are found in the C@SCC5:1 film, whose tensile strength rises from 7.17 MPa to 15.44 MPa. The C@SCC5:1 film has scavenging rates of 95.43 % and 84.67 % against ABTS and DPPH free radicals, respectively, and CA can be released continuously in various food systems. In addition, the antibacterial rate of E. coli O157:H7 and S. aureus of C@SCC5:1 film in meat was 99.9 %, and it can effectively delay lipid oxidation and pH rise. In conclusion,C@SCC5:1 film is a new type of antibacterial and antioxidant food packaging material.

On the chemical fate of propyl gallate as stabilizer in Lyocell spinning dopes

Propyl gallate (PG, gallic acid propyl ester, Tenox®) is a very frequently used stabilizer and antioxidant in food and material applications, also used on large scale in the Lyocell process to stabilize the cellulose spinning dopes. In the present study we have investigated the fate of PG under classical Lyocell conditions (cellulose dissolved in N-methylmorpholine-N-oxide monohydrate at temperatures above 80 °C) by means of multiple analytical techniques, including NMR, GPC, and MS-hyphenated chromatography. It is demonstrated that propyl gallate is quickly hydrolyzed to gallate or, as a side reaction, aminolyzed to gallic acid morpholide. The products of the antioxidative action of gallic acid and propyl gallate, namely ellagic acid and its bis(ortho-quinone), are very easily adsorbed to cellulosic surfaces and are chiefly responsible for the discoloration of Lyocell spinning dopes and the resulting fibers. However, gallic acid morpholide and its parent compound gallic amide, while both having good antioxidant activity similar to propyl gallate itself, do neither form ellagic acid nor the bis(ortho-quinone) and are thus significantly superior to the conventionally used propyl gallate with regard to chromophore generation and resulting brightness loss. Also gallate moieties in tannins can be converted into the amide or morpholide to be further used as Lyocell stabilizers, which might open the way both to new Lyocell stabilizers and to a niche utilization for tannins.Graphical abstract

Anti-Obesity and Anti-Inflammatory Synergistic Effects of Green Tea Catechins and Citrus β-Cryptoxanthin Ingestion in Obese Mice.

Chronic obesity causes various diseases, leading to an urgent need for its treatment and prevention. Using monosodium-glutamate-induced obesity mice, the present study investigated the synergistic obesity-reducing effects of tea catechins and the antioxidant β-cryptoxanthin present in mandarin oranges. The results show that the obese mice that ingested both tea catechin and β-cryptoxanthin for 4 weeks had a significantly decreased body weight, with no difference in body weight compared with control mice. Moreover, the blood biochemical test results were normal, and the body fat percentage was significantly decreased according to the histopathological analysis. Additionally, the abundance of M1 macrophages, which release pro-inflammatories, was significantly reduced in adipose tissue. Indeed, a significant decrease was detected in M1-macrophage-secreted tumor necrosis factor-alpha levels. Meanwhile, M2 macrophage levels were recovered, and adiponectin, which is released from adipocytes and involved in suppressing metabolic syndrome, was increased. Collectively, these results suggest that the combination of tea catechins and antioxidant foods can alleviate chronic obesity, indicating that a combination of various ingredients in foods might contribute to reducing chronic obesity.