Inhibition Of Protein Oxidation Research Articles

Effects of plasma-activated slightly acidic electrolyzed water on salmon myofibrillar protein: Insights from structure and molecular docking

The present study investigated the impact of plasma-activated water (PAW), slightly acidic electrolytic water (SAEW) and plasma-activated slightly acidic electrolytic water (PASW) treatment on myofibrillar protein (MP) in salmon fillets. Additionally, the interaction mechanism between myosin and reactive oxygen species was explored by molecular docking. Compared with the control group (719.26 nm), PASW treatment group exhibited the smallest particle size (408.97 nm). The PASW treatment exhibited efficacy in reducing MP aggregation and inhibiting protein oxidation. In comparison with other treatments, PASW treatment demonstrated a greater ability to mitigate damage to the secondary and tertiary structures of MP. O3 and H2O2 interact with myosin through hydrogen bonding. Specifically, O3 interacts with Lys676, Gly677, and Met678 of myosin while H2O2 binds to Thr681, Asp626, Arg680, and Met678. This study offers novel insights into the impact of PASW on MP, and provides a theoretical foundation for its application in aquatic product processing.

Effects and mechanism of sub-freezing storage on water holding capacity and tenderness of beef

In order to explore the effect of sub-freezing storage on water holding capacity and tenderness of beef, four treatments were compared in this study: sub-freezing (−7 °C) fast sub-freezing (−38 °C until the core temperature achieved to −7 °C), superchilling (−1 °C) and fast frozen (−38 °C until the core temperature achieved to −18 °C) with the latter two treatments serving as the controls. The differences in muscle fiber structure, water distribution, protein oxidation and cytoskeletal protein degradation were studied. The results demonstrated that compared with other treatments, the fast sub-freezing treatment resulted in less structural damage to the muscle fibers and had better water holding capacity. Both sub-freezing and fast sub-freezing treatments inhibited protein oxidation compared with superchilling, but the former treatment's level of protein oxidation was higher than that in fast sub-freezing treatment during long-term storage (42 weeks). In addition, the structural proteins in the sub-freezing and fast sub-freezing treatments underwent faster degradation during long-term storage and therefore the meat was more tender compared with the fast frozen treatment. The results indicate that the fast sub-freezing treatment can be potentially applied in beef storage.

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.

In vitro Screening of Antioxidant and Anti-inflammatory Activities of Plant Extract Adenanthera pavonina

Adenanthera pavonina (AP) is a medicinal herb used in traditional systems of medicine in Sri Lanka. It is considered a rich source of bioactive compounds as they are able to produce a great variety of secondary metabolites with great anticancer and antioxidant properties. In the present study, the bark of the plant was used and water extract was prepared in order to screen Total Phenolic Content (TPC), Total Flavonoid Content (TFC), Ferric ion reducing power, DPPH radical scavenging capacity, inhibition of lipid peroxidation, inhibition of protein oxidation and inhibition deoxyribose oxidation. Anti-inflammatory activity was screened in vitro using Human Red Blood cell Membrane stability assay (HRBM) and inhibition of protein denaturation assay. All methods were carried out according to the standard protocol. The TPC and TFC were 80.3±0.1 mg GA/g (Gallic Acid/g) and 46.1±0.1 mg EGCG/g (epigallocatechin gallate /g) respectively. The DPPH radical scavenging capacity, inhibition of lipid peroxidation, protein oxidation and deoxyribose oxidation were IC50, 15.8±0.5 (Gallic acid, 4.5±0.3 μg/ml), 46.1±0.5 μg/ml (Ascorbic acid , 58.4±2.2 μg/ml), 72.6±3.1 μg/ml (Ascorbic acid, 51.2±0.1 μg/ml) and 7.4±0.7 μg/ml (Ascorbic acid, 8.7±0.6 μg/ml) respectively. Reducing power of the AO extract increased with the concentration. HRBM and inhibition of BSA denaturation of AO extract were IC50 that 49.7±1.4 μg/ml (Diclofenac sodium, 47.8±2.1 μg/ml) and 29.1±1.5 (Diclofenac sodium 23.8±3.6 μg/ml) respectively. The results of the study suggest that the bioactive molecules present in the AP water extract can be used as a prototype for the development of new drugs or as a source of antioxidants and anti-inflammatory pharmaceutical raw material.&#x0D; Keywords: Adenanthera pavonina, Inhibition of lipid peroxidation, Inhibition of protein oxidation, Inhibition deoxyribose oxidation.

Tracking protein aggregation behaviour and emulsifying properties induced by structural alterations in common carp (Cyprinus carpio) myofibrillar protein during long-term frozen storage

The effect of ultrasound-assisted immersion freezing (UIF), air freezing (AF), and immersion freezing (IF) on the protein structure, aggregation, and emulsifying properties of common carp (Cyprinus carpio) myofibrillar protein during frozen storage were evaluated in the present study. The result showed that, compared with AF and IF samples, UIF sample had higher reactive/total sulfhydryl, protein solubility, and lower protein turbidity (P < 0.05), indicating that UIF was beneficial to inhibit protein oxidation and aggregation induced by frozen storage. UIF inhibited the alteration of secondary structure and tertiary structure during frozen storage. Meanwhile, UIF sample had higher emulsifying activity index, and smaller emulsion droplet diameter than AF and IF samples (P < 0.05), suggesting that UIF was beneficial for maintaining the emulsifying properties of protein during storage. In general, UIF is a potential and effective method to suppress the decrease in protein emulsifying properties during long-term frozen storage.

Effect of structurally different pectin combined with polyphenol on water distribution, protein oxidation and heterocyclic amines formation in meat-based snacks

This research studied the effect of structurally different pectin combined with polyphenol (PP) on the physicochemical properties, inhibition of protein oxidation and heterocyclic amines (HAs) formation in fish meat snacks. The findings demonstrated that pectin with a high degree of esterification (DE) and average chain length (ACL) significantly reduced cooking loss, improved zeta potential values, and reduced particle size when combined with polyphenols, indicating an inhibition of protein aggregation and crosslinking. The addition of PP decreased the carbonyl formation as compared to individual polyphenol and control. Low Field Nuclear Magnetic Resonance (LF-NMR) analysis publicized that PP combination increased the water binding capacity, which resulted in less free water (T22 and T23) in those samples. Furthermore, LC/MS analysis revealed that PP combination, retained the water inside the macromolecules and prevented the relocation of water to the surface, which resulted in the less HAs formation as compared to control. The scanning electron microscopy (SEM) revealed that combination of PP samples formed a compact structure evidenced by less wide holes while control sample revealed loose structure. The findings suggest that 201 and 601 pectin combined with catechin have potential to improve the physicochemical properties and inhibition of hazardous compound formation.

Investigating the mechanism of antioxidants as egg white powder flavor modifiers.

The uses of egg white powder (EWP) are restricted because of its odor. It is necessary to find a method to improve its flavor. In this paper, three different antioxidants - green tea extract (GTE), sodium ascorbate (SA), and glutathione (GSH) - were selected to modify the flavor. The physicochemical and structural properties of EWP were investigated to study the mechanism of the formation and release of volatile compounds. Antioxidants can modify the overall flavor of EWP significantly, inhibiting the generation or release of nonanal, 3-methylbutanal, heptanal, decanal, geranyl acetone, and 2-pemtylfuran. A SA-EWP combination showed the lowest concentration of 'off' flavor compounds; GTE-EWP and GSH-EWP could reduce several 'off' flavor compounds but increased the formation of geranyl acetone and furans. The changes in the carbonyl content and the amino acid composition confirmed the inhibition of antioxidants with the oxidative degradation of proteins or characteristic amino acids. The results of fluorescence spectroscopy and Fourier transform infrared (FTIR) spectroscopy provided structural information regarding EWP, which showed the release of volatile compounds decreased due to structural changes. For example, the surface hydrophobicity increased and the protein aggregation state changed. Antioxidants reduce the 'off' flavor of EWP in two ways: they inhibit protein oxidation and Maillard reactions (they inhibit formation of 3-methylbutanal and 2-pemtylfuran) and they enhance the binding ability of heat-denatured proteins (reducing the release of nonanal, decanal, and similar compounds). © 2023 Society of Chemical Industry.

Cryoprotective Effect of NADES on Frozen-Thawed Mirror Carp Surimi in Terms of Oxidative Denaturation, Structural Properties, and Thermal Stability of Myofibrillar Proteins.

Quality degradation due to the formation and growth of ice crystals caused by temperature fluctuations during storage, transportation, or retailing is a common problem in frozen surimi. While commercial antifreeze is used as an ingredient in frozen surimi, its high sweetness does not meet the contemporary consumer demand for low sugar and low calories. Therefore, the development of new green antifreeze agents to achieve an enhanced frozen-thawed stability of surimi has received more attention. The aim of this study was to develop a cryoprotectant (a mixture of citric acid and trehalose) to enhance the frozen-thawed stability of surimi by inhibiting the oxidative denaturation and structural changes of frozen-thawed mirror carp (Cyprinus carpio L.) surimi myofibrillar protein (MP). The results showed that the amounts of free amine, sulfhydryl, α-helix, intrinsic fluorescence intensity, and thermal stability in the control significantly decreased after five F-T cycles, while the Schiff base fluorescence intensity, amounts of disulfide bonds and surface hydrophobicity significantly increased (p < 0.05). Compared to sucrose + sorbitol (SS), the natural deep eutectic solvents (NADES) effectively inhibited protein oxidation. After five F-T cycles, the α-helix content and Ca2+-ATPase activity of the NADES samples were 4.32% and 80.0%, respectively, higher, and the carbonyl content was 17.4% lower than those of the control. These observations indicate that NADES could inhibit oxidative denaturation and enhance the structural stability of MP.

Evaluating β-cryptoxanthin antioxidant properties against ROS-induced macromolecular damages and determining its photo-stability and in-vitro SPF.

Natural antioxidants have become vital to minimize macromolecular damage caused by Reactive Oxygen Species (ROS). This study investigated the antioxidant property of β-cryptoxanthin (β-CRX) extracted fromKocuria marinaDAGII and its protective effect against macromolecular damages by generating ROS via two models: UV radiation and the Fenton reaction. β-cryptoxanthin exhibited the highest scavenging activity towards hydrogen peroxide radicals with an IC50 value of 38.30 ± 1.13μg/ml, favoring the hydrogen atom transfer mechanism. The total antioxidant capacity value of 872.0101 ± 1.84μg BHT/mg β-CRX indicated the cumulative ROS scavenging ability of β-cryptoxanthin. β-cryptoxanthin could protect against ROS-induced lipid peroxidation, protein oxidation, and DNA damage. The highest lipid peroxidation and protein oxidation inhibition values of β-cryptoxanthin against ROS were 99.371 ± 0.51% and 78.19 ± 0.15%, respectively. β-cryptoxanthin also showed a protective effect in maintaining DNA intactness against ROS-mediated DNA damage.Allium cepatest showed the non-genotoxic nature of β-cryptoxanthin and its protective effect against ROS genotoxic effects. A photo-stability study of β-cryptoxanthin toward UVA and UVB radiation showed a rapid bleaching result of UVB obeying pseudo-zero order kinetics with an average R2 value of 0.9897 and a higher k value (-6.3 × 10-11 ± 0.2M/s) than UVA (k value -3.1 × 10-11 ± 0.17M/s), signifying that UVB is more potent toward photo-degradation. The good SPF value of 23.1737 ± 0.15 showed the UV protection capability of β-cryptoxanthin. Thus, the present study suggests that β-cryptoxanthin could be a valuable antioxidant to protect against ROS-induced various macromolecular damages and act as a good UV protectant.

Effect of gamma irradiation treatment on microstructure, water mobility, flavor, sensory and quality properties of smoked chicken breast.

Effect of gamma irradiation on quality, flavor and sensory properties of smoked chicken breasts were investigated. Results indicated irradiation doses >3kGy were effective for sterilization, while also produced a significant effect on overall quality of smoked chicken breast. Irradiation treatment could inhibit protein oxidation and accelerate lipid oxidation of smoked chicken breasts. High irradiation doses could increase the instability of free and bound water, as well as increase muscle fiber gap and juice loss significantly. Irradiation treatment also promoted free fatty acids and taste-presenting nucleotides degradation, effectively increased fresh-tasting amino acids contents and decreased bitter and sweet-tasting amino acids contents. The types and relative contents of volatiles, especially aldehydes, alcohols, aromatic hydrocarbons, and phenolic compounds, also changed after irradiation, while tartaric, pyruvic, and malic acids decreased. Results obtained can provide valuable reference data for improving the quality and flavor of smoked chicken breasts using gamma irradiation technology.

Whey Protein Hydrolysate Improved the Structure and Function of Myofibrillar Protein in Ground Pork during Repeated Freeze-Thaw Cycles.

Whey protein hydrolysate (WPH) has made a breakthrough in inhibiting oxidative deterioration and improving the quality of meat products during storage. Based on our previous study of extracting the most antioxidant active fraction I (FI, the molecular weight < 1 kDa) from whey protein hydrolysates of different molecular weights, the present study continued to delve into the effects of WPH with fraction I on the structure and function of myofibrillar proteins (MP) in ground pork during the freeze-thaw (F-T) cycles. With the number of F-T cycles raised, the total sulfhydryl content, the relative contents of α-helix, Ca2+-ATPase activity, K+-ATPase activity, solubility, emulsion activity index (EAI), and emulsion stability index (ESI) of MP gradually decreased. Conversely, the carbonyl content and the relative content of random curl showed an increasing trend. In particular, the damage to the structure and the function of MP became more pronounced after three F-T cycles. But, during F-T cycles, FI stabilized the structure of MP. Compared to the control group, the 10% FI group showed a remarkable improvement (p < 0.05) in the total sulfhydryl content, Ca2+-ATPase activity, K+-ATPase activity, solubility, EAI and ESI after multiple F-T cycles, suggesting that 10% FI could effectively inhibit protein oxidation and had the influence of preserving MP function properties. In conclusion, WPH with fraction I can be used as a potential natural antioxidant peptide for maintaining the quality of frozen processed meat products.

Ultrasound combined with slightly acidic electrolyzed water thawing of mutton: Effects on physicochemical properties, oxidation and structure of myofibrillar protein.

The effects of air thawing (AT), water immersion thawing (WT), microwave thawing (MT) and ultrasound combined with slightly acidic electrolyzed water thawing (UST) on the myofibrillar protein (MP) properties (surface hydrophobicity, solubility, turbidity, particle size and zeta potential), protein oxidation (carbonyl content and sulfhydryl content) and structure (primary, secondary and tertiary) of frozen mutton were investigated in comparison with fresh mutton (FM). The solubility and turbidity results showed that the MP properties were significantly improved in the UST treatment. UST treatment could effectively reduce the MP aggregation and enhance the stability, which was similar to the FM. In addition, UST treatment could effectively inhibit protein oxidation during thawing as well. The primary structure of MP was not damaged by the thawing methods. UST treatment could reduce the damage to MP secondary and tertiary structure during the thawing process compared to other thawing methods. Overall, the UST treatment had a positive influence in maintaining the MP properties by inhibiting protein oxidation and protecting protein structure.

Dynamic monitoring of the protein-lipid co-oxidation of algae oil-enriched emulsions coated with soybean protein-rutin covalent conjugates

The stabilities and levels of protein-lipid co-oxidation of algae oil-in water (O/W) emulsions coated with the soybean protein 7S/11S or their rutin covalent conjugates were studied during storage. After 96 h of storage, the emulsions stabilized with the covalent conjugates exhibited decreased droplets sizes and ζ-potentials and increased concentrations of adsorbed proteins. Therefore, the covalent binding of rutin in different mixing ratios (at 7S/11S:rutin molar ratios of 1:10 and 1:20) improved the physical stabilities of the emulsions compared with those of the emulsions stabilized by native 7S/11S. The 7S/11S-rutin covalent conjugates, which formed interfacial barriers and exhibited good free radical scavenging properties, inhibited protein oxidation (with lower contents of protein carbonyls, Nʹ-formyl-L-kynurenine, and Schiff bases, and decreased intensities of intrinsic tryptophan fluorescence) and lipid oxidation (with lower contents of lipid hydroperoxide and malondialdehyde) as storage time increased. The electronic nose test distinguished the flavor characteristics of the emulsions coated with different protein-based stabilizers. These results reveal the viability of utilizing soybean protein-rutin conjugates in protein-stabilized algae oil-fortified emulsions with enhanced storability.

Beta vulgaris var. cicla methanol extract prevents the formation of advanced glycation end products and protein oxidation against -glucose, and -fructose-induced protein glycation in vitro

Beta vulgaris is an edible plant and herbal medicine traditionally used to treat diabetes and breast cancer and protect against liver damage induced by an HF diet. The aim of this investigation to evaluate the inhibitory activity of B. vulgaris (CH) extract on the formation of advanced glycation end products (AGEs) against fluorescent and Non-fluorescent AGEs, protein oxidation, and protein aggregation in an in vitro model of glucose and fructose protein glycation and Congo red test. Our study provides evidence that CH significantly reduced fluorescent and no fluorescent (Nε-CML) and fructosamine levels in AGEs-BSA systems during four weeks of study. It also avoided protein oxidation, which was shown by the depletion of protein thiol and reduced protein carbonyl, preventing structural loss of protein and AGEs formation by inhibiting protein oxidation and protein glycation. Furthermore, CH extract also inhibited amyloid cross β-structure and increased GPx enzymatic activity. This study demonstrated that CH has a noticeable antiglycation effect in a varied glycation modification of albumin and can retard or forewarn AGEs-related diabetes type 2.

Effect of interfacial composition on the physical stability and co-oxidation of proteins and lipids in a soy protein isolate-(−)-epigallocatechin gallate conjugate emulsion

In this study, oil-in-water emulsions were co-stabilized by a soy protein isolate-(−)-epigallocatechin gallate (SPI-EGCG) conjugate, tea saponin (TS), and hexadecyltrimethylammonium bromide (CTAB) (0.01–1.00%, w/v), and the influence of the mixed SPI-EGCG-conjugate–surfactant interface on the physical stability and protein–lipid co-oxidation properties of each emulsions was investigated. Our results demonstrated that TS exhibits a better emulsifying ability than CTAB by significantly reducing interfacial tension; this emulsion contained the smallest particles at a TS concentration of 1.0% (w/v). In addition, the interfacial protein content revealed the existence of synergistic (CTAB) and competitive (TS) adsorption between the protein and surfactant. The presence of TS displaced protein molecules at the interface and inhibited protein oxidation, which reveals that proteins adsorbed at the oil–water interface are more sensitive to oxidation than unadsorbed proteins. The degrees of protein and lipid oxidation were enhanced in the presence of CTAB. Furthermore, the addition of TS delayed lipid oxidation; this phenomenon was most pronounced at a TS concentration of 1.0% (w/v). Our results indicate that combining SPI-EGCG conjugates with TS provides an optimal design for the development of nutritionally fortified products with longer shelf lives. • Effects of the surfactant concentration and type on the emulsions were investigated. • TS gave the best emulsification ability and effective interfacial tension reduction. • The co-oxidation of proteins and lipids occurred depending on the protein location.

An integrated biomarker assessment of biochemical responses in a freshwater fish species after vanadium pentoxide (V2O5) exposure.

Vanadium (V) is a toxicant becoming increasingly concentrated in freshwater with the potential to affect aquatic organisms. Vanadium pentoxide (V2O5), accumulated in fish, can act as an oxidizing agent and cause oxidative damage. To determine the effects of V2O5 on exposed adult Oreochromis mossambicus, acute exposure experiments were conducted. Bioaccumulation and biomarker analyses were performed on various excised tissues of the exposed fish. As expected, accumulated V concentrations in the gills increased as the exposure concentration increased. Gill tissue accumulated more vanadium than muscle tissue. Metallothionein content increased in the highest concentrations compared to the lower concentrations, therefore showing that metallothionein proteins were attempting to sequester V2O5 in the tissues. Superoxide dismutase (SOD) showed an excitation at lower concentrations and inhibition as the exposure concentrations increased, possibly due to ROS detoxification. Catalase activity decreased from the first exposure concentration to the last concentration; this could have been due to SOD compensation. Protein carbonyl concentration decreased as the concentrations of V2O5 increased, indicating an inhibition of protein oxidation. The IBRv2 comparison revealed the biochemical responses caused by V2O5 more effectively than traditional statistical analysis.

Improved physicochemical properties and product characteristics of tilapia surimi by tea polyphenols during chilled storage

The decline of physicochemical properties of surimi during storage limits its application for surimi product processing. In this study, the effect of tea polyphenols (TP) on the physicochemical properties and product characteristics of tilapia surimi during chilled storage was studied. With the increase of storage time, the total volatile basic nitrogen, malondialdehyde, and protein degradation index obviously increased, while the pH value, total sulfhydryl content, protein solubility, water-holding capacity (WHC), hardness, and whiteness obviously decreased. The addition of TP, especially at 300 mg/kg, significantly inhibited the lipid and protein oxidation and protein degradation in tilapia surimi, followed by the improved WHC and hardness of its product especially in late storage (5–7 d). Principal component analysis showed that 300 mg/kg TP-treated tilapia surimi after 7 d storage showed similar properties to TP-free tilapia surimi after 2 d storage, suggesting the good effect of TP on prolonging its storage life. The correlation network model based on the Pearson's correlation analysis revealed that the inhibition of protein oxidation, polymerization, and degradation in tilapia surimi by TP contributed most to the improvement of WHC and hardness in its product. TP can be developed as a potential protector for the tilapia surimi during chilled storage.

Effects of nitrite concentrations on the quality and protein oxidation of salted meat.

The objective of this study was to investigate the effects of different concentrations of sodium nitrite on the quality and protein oxidation of salted meat during 21 days of curing. The salted meat was treated with sodium nitrite at 50, 100, and 150 mg/kg for curing, and salted meat without sodium nitrite was used as a control. The results showed that in salted meat added with sodium nitrite, the carbonyl group, disulfide bond, dityrosine, surface hydrophobicity, and the transformation rate from α-helix to β-sheet were all significantly reduced, whereas the sulfhydryl group content of myofibrillar proteins was significantly increased compared to the control. Meanwhile, the total volatile basic nitrogen and aerobic plate content were significantly decreased, while both the pH and a* value were significantly increased with an increase in nitrite concentration compared to the control group. Importantly, this phenomenon was also observed in salted meat treated with low doses of sodium nitrite (50 mg/kg). In conclusion, the quality of salted beef can be improved by adding low-dose sodium nitrite to inhibit protein oxidation during the curing process. PRACTICAL APPLICATION: A low dose of sodium nitrite inhibited the rate of α-helix to β-sheet transformation of myofibrillar proteins in salted meat, reducing the exposure of hydrophobic groups and decreasing the production of protein oxidation products and TVB-N to improve the quality of salted meat. These results provided a theoretical basis and technical guidance for the application of low-dose sodium nitrite in meat processing enterprises.

Antioxidant potential of various extracts from 5 common European mosses and its correlation with phenolic compounds

Summary Introduction: This paper presents the results of research about the antioxidant properties of extracts from 5 moss species, namely Brachythecium rutabulum, Callicladium haldanianum, Hypnum cupressiforme, Orthodicranum montanum and Polytrichastrum formosum. The macerates of each above mentioned species in water and ethanol (50% and 96%) solutions were analysed. Objective: Total phenolic acids, total flavonoids and total flavonols concentrations and content of carotenoids was determined. Also some phenolic compounds were determined by HPLC. Methods: The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and the advanced oxidation protein products (AOPP) formation inhibition were studied. Results: The obtained results showed that the extracts prepared with 50% ethanol had the strongest radical scavenging activities. Every 50% ethanol extract also inhibited formation of AOPP. 96% ethanol extracts had the lowest free radical scavenging activities, although B. rutabulum extract strongly inhibited protein oxidation. Pearson’s correlation showed that the radical scavenging effects of water extracts and extracts prepared with 50% ethanol are dependent on the presence of phenolic acids and flavonoids. Conclusion: The results suggest the moss extracts as materials for potential use in pharmacy or cosmetology.

The protective effect of Jerusalem artichoke polysaccharides against oxidative damage to biomolecules

AAPH and hydroxyl radicals were used to induce oxidative damage to biomolecules (lipid, DNA, protein), and the inhibitory effect of Jerusalem artichoke polysaccharides (JAPS) on oxidative damage was evaluated. The results showed that Jerusalem artichoke polysaccharides had a good inhibitory effect on the oxidative damage of lipids and DNA caused by AAPH and hydroxyl radicals. In the concentration range of 0.5-50.0 μg/mL, the degree of inhibition of Jerusalem artichoke polysaccharides on lipid peroxidation and DNA oxidation increased at first and then decreased. The protective effect of Jerusalem artichoke polysaccharides was the best at a concentration of 5.0 μg/mL. However, Jerusalem artichoke polysaccharides performed weakly in inhibiting protein oxidation, and they even exerted prooxidative effect in hydroxyl radical reaction system. These results may provide some preliminary information to further study Jerusalem artichoke polysaccharides and to help in better utilization of Jerusalem artichoke.