Excellent Antioxidant Capacity Research Articles

Atomically precise gold nanoclusters as ROS-scavenging clusterzymes to treat high-fat diet-induced obesity

Obesity is widely considered a chronic inflammatory disease and is recognized as one of the major challenges to global public health, but there is no successful anti-inflammatory therapy for obesity so far. In this study, atomically precise Au22 nanoclusters are introduced as reactive oxygen species (ROS)-scavenging clusterzymes, with the aim of achieving anti-inflammation in high-fat diet (HFD)-induced obesity. Au22 clusterzymes display high catalase (CAT)-like and superoxide dismutase (SOD)-like activities, excellent antioxidant capacity. We demonstrate that Au22 clusterzymes treatment can effectively scavenge ROS, relieve the antioxidant system disorder, and restrain the inflammation in HFD-induced obese mice, with good biocompatibility. After 30 days of Au22 clusterzymes treatment, high therapeutic efficacy in anti-obesity is observed in HFD-induced obese mice, including decreased body weight by 13%, reduced serum levels of key inflammatory factors (IL-1β, IL-6, and TNF-α) in the obese mice by 23 – 48%, improved glucose tolerance and lipid metabolism, and increased browning of white adipose tissue (WAT). Overall, Au22 clusterzymes have good performance on ROS-scavenging and anti-inflammation in vivo, offering a promising approach to combat obesity and related metabolic diseases.

Optimization of Fermentation Culture Medium for Sanghuangporus alpinus Using Response-Surface Methodology

The newly identified Sanghuangporus alpinus species of the Sanghuang mushroom genus has been found to possess significant medical benefits. However, the current artificial cultivation technology has not reached the requisite maturity. The response-surface methodology (RSM) was used to optimize the Sanghuangporus alpinus culture medium formulation and evaluate the functional activity of S. alpinus exopolysaccharides. First, a single-factor experiment was conducted to screen for optimal carbon and nitrogen sources for S. alpinus. Then, using Box–Behnken’s central composite design, a response-surface experiment was conducted to determine optimal culture parameters. Finally, the rationality of those parameters was assessed in a shaking flask experiment. The optimal culture parameters, determined through regression analysis, were 20.20 ± 0.17 g/L fructose (carbon source), 7.29 ± 0.10 g/L yeast extract (nitrogen source), and 0.99 ± 0.01 g/L dandelion. With optimization, the S. alpinus yield increased to 12.79 ± 1.41 g/L, twice that obtained from the initial culture medium. The S. alpinus exopolysaccharide exhibited an excellent antioxidant capacity, with the strongest scavenging effect noted on ABTS free radicals (lowest half-inhibitory concentration: 0.039 mg/mL). Additionally, this exopolysaccharide effectively inhibited various cancer cells, exhibiting the strongest activity against human glioma cells U251 (half-inhibitory concentration: 0.91 mg/mL). The RSM used to optimize the fermentation culture parameters of S. alpinus significantly increased the mycelial biomass. The improvement of Sanghuangporus alpinus yield through liquid fermentation and optimizing the fermentation medium could fill the existing gap in the cultivation of Sanghuangporus alpinus, as well as provide valuable data for the large-scale production of S. alpinus.

Formulation and Quality Evaluation of Chicken Nuggets Supplemented with Beef and Chicken Livers.

This study explores the potential of utilizing meat byproducts, specifically chicken and beef liver, to enhance the nutritional value of processed foods like chicken nuggets. Proximate analysis was conducted on the livers, including moisture, ash, fat, and protein content, and degradation potential was observed. Antioxidant potential was analyzed through 2,2-diphenyl-1-picrylhydrazyl (DPPH). The total phenolic content (TPC), oxidative stability through peroxide value (POV), and free fatty acid (FFA) were performed to evaluate quality changes during seven-day storage. The radical scavenging activity showed that beef liver has excellent antioxidant capacity (61.55%- and 195.89-mM gallic acid equivalent for DPPH and TPC, respectively) compared to chicken liver and significantly increased the antioxidant potential of nuggets by 5%-10%. POV and FFA values increased with increased storage days for the liver and its incorporation in nuggets. However, the values remained under the 10 meq/kg threshold. Incorporating the livers into chicken nuggets led to a significant (p=0.000) improvement in nutritional content, particularly a 1.5%-2% increase in protein, with a similar increase in mineral content. Texture and sensory evaluations indicated favorable consumer acceptability for liver-enriched nuggets. Overall, this research shows the value of adding liver as a functional ingredient to enhance the nutritional profile of processed foods.

Metal-organic frameworks-based moisture responsive essential oil hydrogel beads for fresh-cut pineapple preservation

The preservation of fresh-cut fruits and vegetables has attracted attention to the shelf-life reduction caused by high humidity. Herein, alginate/copper ions cross-linking, in-situ growth and self-assembly techniques of metal-organic frameworks (MOFs) were utilized to prepare a moisture responsive hydrogel bead (HKUST-1@ALG). As the multistage porous structure formation, tea tree essential oil (TTO) load capacity in hydrogel bead (TTO-HKUST-1@ALG) was increased from 6.1% to 21.6%. TTO-HKUST-1@ALG had excellent moisture response performance, and the release rates of TTO increased from 33.89% to 70.98% with moisture increasing from 45% to 95%. Besides, TTO-HKUST-1@ALG exhibited excellent antimicrobial, antioxidant capacity, and biocompatibility. During storage, TTO-HKUST-1@ALG effectively improved the cell membrane integrity by maintaining the balance of reactive oxygen species metabolism. The degradation of cell wall structure and tissue softening were delayed by inhibiting the cell wall-degrading enzymes activity. Briefly, TTO-HKUST-1@ALG improved the storage quality and extended shelf-life of fresh-cut pineapple, which was a promising preservative.

Hydrogel loaded with thiolated chitosan modified taxifolin liposome promotes osteoblast proliferation and regulates Wnt signaling pathway to repair rat skull defects

To alleviate skull defects and enhance the biological activity of taxifolin, this study utilized the thin-film dispersion method to prepare paclitaxel liposomes (TL). Thiolated chitosan (CSSH)-modified TL (CTL) was synthesized through charge interactions. Injectable hydrogels (BLG) were then prepared as hydrogel scaffolds loaded with TAX (TG), TL (TLG), and CTL (CTLG) using a Schiff base reaction involving oxidized dextran and carboxymethyl chitosan. The study investigated the bone reparative properties of CTLG through molecular docking, western blot techniques, and transcriptome analysis. The particle sizes of CTL were measured at 248.90 ± 14.03 nm, respectively, with zeta potentials of +36.68 ± 5.43 mV, respectively. CTLG showed excellent antioxidant capacity in vitro. It also has a good inhibitory effect on Escherichia coli and Staphylococcus aureus, with inhibition rates of 93.88 ± 1.59 % and 88.56 ± 2.83 % respectively. The results of 5-ethynyl-2 ′-deoxyuridine staining, alkaline phosphatase staining and alizarin red staining showed that CTLG also had the potential to promote the proliferation and differentiation of mouse embryonic osteoblasts (MC3T3-E1). The study revealed that CTLG enhances the expression of osteogenic proteins by regulating the Wnt signaling pathway, shedding light on the potential application of TAX and bone regeneration mechanisms.

Effect of portulaca (Portulaca oleracea L.) extract on the quality and physicochemical attributes of vacuum-packed seasoned steaks during chilled storage.

Vacuum packaging has the ability to reduce oxidative deterioration and microbial-induced spoilage of meat. However, in an oxygen-free environment, it can lead to the development of an unappealing purplish-red color and a decrease in the water-holding capacity of meat, thereby impacting the overall meat quality. Portulaca oleracea L. (POL) is a homology of medicine and food known for its exceptional antioxidant and antimicrobial properties. The aim of our present study was to investigate the antioxidant and antimicrobial ability of n-butanol phase extract of POL and the effect of POL extract incorporation on the quality (water-holding capacity, shear force, color, and texture) and physicochemical (pH, total volatile base nitrogen, and total viable counts) attributes of vacuum-packed seasoned steaks at 4 °C over a 15-day period. Results showed that the POL extract had excellent antioxidant and antimicrobial capacity. Furthermore, the addition of POL extract significantly inhibited protein oxidation and microbial growth of steaks (P < 0.05), and improved the water-holding capacity, color properties, and tenderness (P < 0.05). Moreover, there were no significant differences (P > 0.05) in the color, water-holding capacity, or tenderness between the 0.5and 1 g kg-1 POL extract treatment groups compared to the sodium nitrite control group. These results indicate that POL extract had the potential to replace sodium nitrite due to its ability to hinder protein oxidation and microbial growth of vacuum-packed seasoned steaks, while enhancing the color, water-holding capacity, and tenderness of seasoned steaks. © 2024 Society of Chemical Industry.

Utilization of the waste aqueous phase from tea residue hydrothermal carbonization for preparing active food packaging films

Hydrothermal carbonization (HTC) is an effective strategy for high-value utilization of tea residue (TR), and it was noticed the aqueous phase (AP) has not been extensively studied. This study aimed to investigate the chemical components and characteristics of the AP, and applied it in active food packaging films. The results showed that the total phenolic content of AP was 1.86 mg GAE/mL, and the main compounds in AP were organic acids, alcohols, and amino acids. The AP showed excellent antibacterial activity and antioxidant capacity. The active films were prepared using the casting method. The 4:7-AP/PVA film showed outstanding mechanical properties (tensile strength = 34.18 MPa, elongation at break = 458.67%), antioxidant ability (DPPH scavenging capacity 92.01%), antibacterial activity, water resistance and biocompatibility. The banana preservation test showed the AP/PVA films could successfully prolong the shelf-life of bananas and have the potential to be food packaging films.

Modification mechanism of soybean protein isolate-soluble soy polysaccharide complex by EGCG through covalent and non-covalent interaction: Structural, interfacial, and functional properties

Soybean protein isolate was modified with polysaccharides and polyphenols to prepare a natural emulsifier with antioxidant capacity. Physicochemical, structural, interfacial, and functional properties of SPI-SSPS complex were investigated after covalent and non-covalent interacted with EGCG. SPI-SSPS-EGCG ternary complex with low EGCG concentrations (0.0625 and 0.125 mg/mL) showed a significant increase in absolute potential value and a decrease in turbidity. EGCG destroyed the original rigid structure of SPI-SSPS complex, and the covalent complexes had an ordered structure, while the non-covalent interaction resulted in disordered. The ternary complex with high EGCG concentrations (0.25 and 0.5 mg/mL) exhibited stronger EGCG binding capacity and lower surface hydrophobicity, which in turn affected its interfacial properties. The EAI and ESI of SPI-SSPS-EGCG covalent complex increased significantly, while the non-covalent complex had a significant change in EAI but no significant change in ESI with increasing EGCG concentration. The ternary complex showed significantly enhanced antioxidant capacity. The SPI-SSPS-EGCG ternary complex, with excellent antioxidant capacity and emulsifying property, making it suitable for emulsion delivery systems.

Construction, characterization and bioactivity evaluation of curcumin nanocrystals with extremely high solubility and dispersion prepared by ultrasound-assisted method

Curcumin (Cur) as a natural pigment and biological component, can be widely used in food and beverages. However, the water insolubility of Cur significantly limits its applications. In this study, we prepared a series of nanocrystals via ultrasound-assisted method to improve the solubility and availability of Cur. The results showed artemisia sphaerocephala krasch polysaccharide (ASKP), gum arabic (GA) and wheat protein (WP) were outstanding stabilizers for nanocryatals except traditional agent, poloxamer 188 (F68). The obtained curcumin nanocrystals (Cur-NC) displayed a rod-shaped, crystal- and nanosized structure, and extremely high loading capacity (more over 80 %, w/w). Compared with raw powder, Cur-NC greatly improved the water solubility and dispersibility, and the slow and complete release of Cur of Cur-NC also endowed them excellent antioxidant capacities even at 10 μg/mL. Importantly, as functional factor additive in beverages (e.g. water and emulsion), Cur-NC could increase the content of Cur to at least 600 μg/mL and retain a good stability. Overall, we provided an effective improvement method for the liposoluble active molecules (e.g. Cur) based on the nanocrystals, which not only tremendously enhanced its water solubility, but also strengthened its bioactivity. Notably, our findings broadened the application of water-insoluble compounds.

Chitosan oligosaccharide improves intestinal homeostasis to achieve the protection for the epithelial barrier of female Drosophila melanogaster via regulating intestinal microflora.

The epithelial barrier plays an important role in the organism's health. Chitosan oligosaccharide (COS), a new potential prebiotic, exhibits excellent antioxidant capacity and anti-inflammatory effects. Our study elucidated the protective mechanisms of COS on the intestinal barrier of Drosophila melanogaster under oxidative stress, which could provide new insights into COS application in various industries, such as food, agriculture, and medicine.

A novel fullerene composite material for directional oil control and antioxidant.

There are very few cosmetic ingredients that can target oil control and extend the wear time. Fullerenes have been reported to have excellent antioxidant capacity and a variety of biological activities, such as quenching free radicals, inhibiting lipid peroxidation, and promoting lipid flocculation. The purpose of applying foundation makeup on the face is to make the skin color even, but the secretion and oxidation of skin oil will make the makeup mottled and dull. In order to solve this problem, a fullerene composite material that can directionally absorb oil and resist oil oxidation has been developed. Fullerenes and hydroxyapatite composite was prepared by high pressure homogenization under alkaline condition. The indicated morphology and structure were characterized by SEM, UV-Vis, Raman, and XRD. The oil absorption capacity was determined by adding the C60-hydroxyapatite composite to a mixed solution of hexane and oil, shaking for 1 h, filtering, analyzed by GC-MS, and calculating the oil absorption by external standard method. Artificial sebum was prepared by adding different mass of water and oleic acid to screen the optimum ratio. C60-hydroxyapatite mixture and C60-hydroxyapatite composite were added to the artificial sebum to test the oil-absorbing capacity of the materials. The hydroxyl radical scavenging ability of C60-hydroxyapatite composite containing different fullerene contents was measured by X-band ESR spectroscopy, and the long-term radical scavenging ability of the composites was tested in comparison with VC. Antioxidant experiment is adding C60-hydroxyapatite composite material, and hydroxyapatite to oleic acid, then the UV light irradiation is aimed to accelerate the oxidation of oleic acid. Oleic acid act as a control group, and make the detection of oleic acid peroxide value after 7 days. The safety of the materials was tested by using culture media to soak the C60-hydroxyapatite composite for 24 h and then used to culture cells. The characterization of SEM, UV-Vis, Raman, and XRD showed that fullerene clusters were dispersed on the surface of hydroxyapatite stably, and they formed a stable composite. The adsorption rates of C60-hydroxyapatite composites for oleic acid, phenyl trimethicone, caprylic capric glyceride, isooctyl palmitate, mineral oil, olive oil, and dimethicone were 60.5%, 9.3%, 9.15%, 5.24%, 2.94%, 1.01%, and 0%, respectively. The flocculation amount of artificial sebum was 5.9 g per gram of C60-hydroxyapatite mixture and 24.2 g per gram of C60-hydroxyapatite composite. C60-hydroxyapatite composites have excellent quenching ability for hydroxyl radicals. When the fullerene content is 1, 2, 3, and 4 mg/kg, the quenching rates are 25.02%, 39.57%, 49.75%, and 62.24%, respectively. The quenching effect was enhanced with the increase of fullerene content, and it had strong long-term antioxidant properties. It can also be proved that C60-hydroxyapatite composites have strong antioxidant capacity through antioxidant experiments. The peroxide value of oleic acid on Day 0 was 2.8, and after 7 days of UV irradiation, the peroxide values of blank control, hydroxyapatite group, C60-hydroxyapatite composite containing 0.5% and 1% fullerenes four groups of materials were 8.02 meq O2/kg, 7.98 meq O2/kg, 7.11 meq O2/kg, and 6.87 meq O2/kg, respectively. The cell activity was 20.94% and 99.2% after the cells were cultured for 24 h using C60-hydroxyapatite composite and hydroxyapatite extracts, respectively, and the addition of fullerene was able to significantly increase the cell activity. Fullerene hydroxyapatite complex has excellent directional oil absorption characteristics, which can effectively remove free radicals and reduce skin oil oxidation.

Pickering emulsion stabilized by sugarcane leaf polyphenols-zein covalent nanoparticles for curcumin delivery: In-vitro and inhibition of oxidative hemolytic activity evaluation

Pickering emulsion have been widely used to encapsulate bioactives with the aim of preventing degradation, improving bioavailability and achieving the effect of slow release. Curcumin (Cur), as a bioactive compound, was famous as its excellent beneficial human health functions. However, the low solubility and susceptibility to environmental influences limit the application of Cur. In our previous study, the covalent nanoparticles (sugarcane leaf polyphenols-zein, SGLpZ) with excellent antioxidant capacity were successfully fabricated. In addition, the pickering emulsion stabilized using SGLpZ with significance storage stability and antioxidant properties, which inspired us for Cur delivery application. Therefore, in this study, SZP (pickering emulsion stabilized by SGLpZ) were prepared and were firstly used to delivery Cur evaluation. Results exhibited that the mechanism of excellent stabilization of SZP may be due to the wide range of O/W phase interfaces with SGLpZ, which could be further used as a delivery system for Cur. An in-vitro simulated digestion suggested that SZP provided better protection to Cur under three different conditions (different Na+ concentration, temperatures and UV exposure times), compared to ZZP (pickering emulsion stabilized by zein nanoparticles alone). SZP was able to achieve a slow release of Cur as well as the high bioaccessibility of Cur during the in-vitro simulated digestion. Finally, Cur, Cur-ZZP and Cur-SZP inhibited respectively by 33.20±1.00%, 53.26±0.94% and 71.59±0.14% (p＜0.05) at the Cur concentration of 20 μg/mL in the in-vitro inhibition of AAPH-induced erythrocyte hemolysis assay. The study indicated that the pickering emulsion stabilized by SGLpZ was a reliable Cur delivery system and provided a novel idea of food material application for bioacitive substances delivery.

Therapeutic Application of Dendrobium fimbriatum Hook for Retinopathy Caused by Ultraviolet Radiation and Chemotherapy Using ARPE-19 Cells and Mouse Retina.

Retinopathy caused by ultraviolet radiation and cancer chemotherapy has increased dramatically in humans due to rapid environmental and social changes. Therefore, it is very important to develop therapeutic strategies to effectively alleviate retinopathy. In China, people often choose dendrobium to improve their eyesight. In this study, we explored how Dendrobium fimbriatum extract (DFE) protects ARPE-19 cells and mouse retinal tissue from damage of ultraviolet (UV) radiation and chemotherapy. We evaluated the antioxidant capacity of DFE using the 1,1-diphenyl-2-trinitophenylhydrazine (DPPH) assay. The protective effects of DEF from UV- and oxaliplatin (OXA)-induced damage were examined in ARPE-19 cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and immunofluorescence (IF) stains, and in mouse retinal tissue using immunohistochemistry (IHC) stains. Our results show that DFE has excellent antioxidant capacity. The ARPE-19 cell viability was decreased and the F-actin cytoskeleton structure was damaged by UV radiation and OXA chemotherapy, but both were alleviated after the DFE treatment. Furthermore, DFE treatment can alleviate OXA chemotherapy-induced reduced expressions of rhodopsin and SOD2 and increased expressions of TNF-α and caspase 3 in mouse retinal tissue. Thus, we suggest that DFE can act as suitable treatment for retinopathy through reducing oxidative stress, inflammation, and apoptosis.

Arabinoxylan hydrolysates improved physical and oxidative stability of oil-in-water emulsions

This study was to improve the physical and oxidative stability of sodium caseinate (NaCas)-stabilized oil-in-water (O/W) emulsions with arabinoxylan hydrolysates (AXHs). AXHs with different molecular sizes were prepared using xylanase treatment for 0 (AXH0), 30 (AXH30), 60 (AXH60), and 120 (AXH120) min, respectively. Compared with the emulsion without AXHs, all AXHs emulsions showed increased coalescence stability, evidenced by no change occurred in the droplet size with the pH variation from 7.0 to 5.0. Moreover, at pH 7.0 and 5.0, AXH60 and AXH120 emulsions showed no flocculation, coalescence, or creaming before and after 21 d storage. All the AXH samples showed excellent antioxidant capacities, demonstrated by the slow accumulation of lipid hydroperoxides and thiobarbituric acid reactive substances during storage. In sum, rice bran arabinoxylans hydrolyzed ≥60 min possess a potential as effective antioxidants to form physically and oxidatively stable O/W emulsions at pH above the emulsifier pI, and substances with high antioxidant activity below the emulsifier pI still need to be explored.

Polysaccharides from waste Zingiber mioga leaves: Ultrasonic-microwave-assisted extraction, characterization, antioxidant and anticoagulant potentials

Zingiber mioga is a highly economic crop that is used to produce vegetables, spices and herbal pharmaceuticals. Its edible flower bud contributes most to the economic value, but the big leaves were discarded as agricultural waste, which urgently needs to be exploited. In this work, polysaccharides from waste Z. mioga leaves (PWZMLs) were extracted using ultrasonic-microwave-assisted extraction (UMAE). After purification and characterization, the antioxidation and anticoagulation of PWZMLs were evaluated to appraise the potential in cardiovascular protection. Under the liquid–solid ratio of 26: 1 mL/g, after ultrasonication at 495 W for 10 min, followed by microwaving at 490 W for 5 min, the yield of PWZMLs achieved to 6.22 ± 0.14 %, notably higher (P < 0.01) than other methods, and ultrasound contributed more to the yield than microwave. Various analyses confirmed that PWZMLs were negatively charged polysaccharides with galacturonic acid the dominant uronic acid. PWZMLs exerted excellent antioxidant capacity, especially for scavenging 1, 1-diphenyl-2-picrylhydrazyl radical. PWZMLs also elicited promising anticoagulant property, particularly for prolonging activated partial thromboplastin time and lowering fibrinogen, which were almost equivalent to heparin at the same concentration. PWZMLs contained two polysaccharide fractions (199.53 and 275.42 kDa) that could synergistically contribute to the pronounced antioxidant and anticoagulant activities. The PWZMLs extracted with optimized UMAE have great potential in cardiovascular protection.

Development of an edible food packaging gelatin/zein based nanofiber film for the shelf-life extension of strawberries.

An edible food packaging gelatin/zein nanofiber film co-loaded with cinnamaldehyde (CA)/thymol (THY) was developed, which possessed outstanding features conducive to strawberries preservation. Firstly, the synergistic antibacterial behavior of CA and THY was investigated. Then CA and THY were co-loaded into gelatin/zein nanofiber films by electrospinning technology. The addition of CA and THY increased water contact angle to 85.1° after 10s and decreased the water vapor transmission rate of 3.1×10-8 g·mm-1·h-1·Pa-1. The tensile strength was 1.30MPa and the elongation at break was 185%. The nanofiber films exhibited good shielding effect of ultraviolet-visible light and excellent antioxidant capacity with DPPH free radical scavenging percentage of 99.9% in 4h. The nanofiber films (12.5mg/mL) could achieve significant inhibition effects on Escherichia coli ATCC 25922 with the bacteriostatic ratio of 67.5%, Staphylococcus aureus ATCC 6538 and Listeria monocytogenes ATCC 19115 with the antibacterial ratios of 100%. A real-time study on the nanofiber films as fruit packaging materials was carried out on strawberries and the packaged strawberries kept their freshness as long as 7days at room temperature. Therefore, the GZ/CT nanofiber film prepared in this work has good application potential in the field of fruit packaging.

Impact of Gamma irradiation pretreatment on the characteristics of native and defatted date palm seed flour and oil

Numerous beneficial compounds in date seeds are less accessible due to natural barriers. These compounds can be especially beneficial to human health when linked to their excellent antioxidant capacity. The aim of this study is to elucidate the effect of gamma irradiation on releasing these compounds in order to enhance the chemical composition of native and defatted date seed powder. To achieve this, date seed flour was exposed to two doses of gamma irradiation (1 and 5 kGy), and then the irradiated samples were assessed for their chemical properties. Additionally, after irradiation pretreatment, oil extraction was carried out using different solvents, and the native and defatted date seed flours were analyzed. The results showed that gamma irradiation had a significant effect on the color and chemical composition of the date seed powder. The solubility of amino acids in solvents was affected by gamma irradiation, resulting in defatted seed flours that were richer in some amino acids. Furthermore, irradiated-defatted seed powder exhibited higher levels of neutral sugars and esterified phenols, which contribute to a better antioxidant capacity. FTIR spectra confirmed that, after irradiation, there was a breakdown of the cell wall structure, allowing for a higher oil yield with more effective antimicrobial activities. In conclusion, irradiation pretreatment allowed the native and defatted date seed flour to gain additional benefits by making chemical compounds more extractable.

A new strategy for maintaining the thermal stability of phycocyanin under acidic conditions: pH-induced whey protein isolate-phycocyanin coprecipitation forms composite with chitosan

Phycocyanin is prone to degradation under acidic conditions and unstable at high temperatures, which is a key scientific issue limiting its application in food. Many methods have been used to maintain the stability of phycocyanin, but no excellent method has emerged. In order to achieve the application of phycocyanin in food (especially in beverages), this study innovatively utilized an effective method to combine phycocyanin with whey protein isolate by protein coprecipitation, and then coat it with chitosan to form composite particles. The composite particles not only maintained the blue color of phycocyanin, but also had colloidal stability. By simulating the conditions of pasteurization, high temperature short-term sterilization (HTST) and ultrahigh temperature transient sterilization (UHT), the color of the whey protein isolate (WPI) - phycocyanin (PC) - chitosan (CS) composite solutions (pH = 3) changed slightly before and after heating, without significant apparent differences. The UV–vis spectra showed that the highest and lowest pigment retention rates of WPI-PC-CS composite can reach 96.41% and 81.63%, respectively. The results of particle size, ζ-potential, SDS-PAGE, intrinsic fluorescence and FTIR analysis showed that phycocyanin was encapsulated in the helical structure of whey protein isolate, and chitosan was effectively attached to the surface of coprecipitated particles. Meanwhile, WPI-PC-CS composite also had excellent antioxidant capacity after heating. WPI-PC-CS composite had broken through the limitations of other materials in food applications and expanded the application of phycocyanin in acidic beverages and other food forms.

Lycopene Prevents Phthalate-Induced Cognitive Impairment via Modulating Ferroptosis.

Di-(2-ethylhexyl) phthalate (DEHP) is frequently used as a plasticizer in industrial and agricultural products. DEHP can cause severe neurotoxicity, such as impaired learning and memory function. Lycopene (LYC) as a carotenoid exerts excellent antioxidant capacity and therapeutic effects in neurodegenerative diseases. However, whether LYC can prevent the cognitive impairment induced by DEHP and the specific mechanisms are unclear. In the present study, the behavioral test results suggested that LYC alleviated the learning and memory impairment induced by DEHP. The histopathological data revealed that LYC attenuated DEHP-induced disordered arrangement of the neurons in the CA1 and CA3 regions of the hippocampus tissue. Moreover, LYC inhibited the occurrence of DEHP-induced ferroptosis via regulating iron metabolism, inhibiting lipid peroxidation, and activating the cysteine transporter and nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (NrF2/HO-1) signaling pathway. Overall, the study contributes novel perspectives into the potential mechanisms of LYC preventing phthalate-induced cognitive impairment in the hippocampus.

Fe-NC nanozymes-loaded TiO2 nanotube arrays endow titanium implants with excellent antioxidant capacity for inflammation inhibition and soft tissue integration

Titanium (Ti) and its alloys have been widely used as percutaneous and subcutaneous implants due to their excellent mechanical properties and biocompatibility. However, the aggregation of reactive oxygen species (ROS) and persistent inflammatory responses at the implant site severely affect the soft tissue integration of Ti implants, causing a series of biological complications. To address this issue, in this study, Fe-nitrogen-doped carbon single-atom nanozymes (Fe-NC nanozymes) loaded titanium oxide nanotube arrays (Fe-NC@TNT) were constructed by anodic oxidation and solvothermal method on medical titanium surfaces. The surface morphology, physical composition, enzyme-like catalytic activity, inflammatory response, and soft tissue compatibility of Fe-NC@TNT were investigated. The unique nanotube array fully exposes the catalytic active sites of Fe-NC nanozymes and significantly enhances their enzyme-like catalytic performance to eliminate superoxide anion, hydrogen peroxide, and more toxic hydroxyl radicals, which could effectively reduce the intracellular ROS levels of macrophages and fibroblasts, thereby inhibiting the inflammatory responses of macrophages and promoting the functional expression of fibroblasts. In vivo animal experiments have further demonstrated that Fe-NC@TNT can effectively regulate the immune response and promote the integration between the implant and the surrounding soft tissues.