Superoxide Radical Scavenging Ability Research Articles

Preparation and Antioxidant Activity of New Carboxymethyl Chitosan Derivatives Bearing Quinoline Groups.

A total of 16 novel carboxymethyl chitosan derivatives bearing quinoline groups in four classes were prepared by different synthetic methods. Their chemical structures were confirmed by Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and elemental analysis. The antioxidant experiment results in vitro (including DPPH radical scavenging ability, superoxide anion radical scavenging ability, hydroxyl radical scavenging ability, and ferric reducing antioxidant power) demonstrated that adding quinoline groups to chitosan (CS) and carboxymethyl chitosan (CMCS) enhanced the radical scavenging ability of CS and CMCS. Among them, both N, O-CMCS derivatives and N-TM-O-CMCS derivatives showed DPPH radical scavenging over 70%. In addition, their scavenging of superoxide anion radicals reached more than 90% at the maximum tested concentration of 1.6 mg/mL. Moreover, the cytotoxicity assay was carried out on L929 cells by the MTT method, and the results indicated that all derivatives showed no cytotoxicity (cell viability > 75%) except O-CMCS derivative 1a, which showed low cytotoxicity at 1000 μg/mL (cell viability 50.77 ± 4.67%). In conclusion, the carboxymethyl chitosan derivatives bearing quinoline groups showed remarkable antioxidant ability and weak cytotoxicity, highlighting their potential use in food and medical applications.

Effects of Solid-State Fermentation with the Ganoderma spp. and Coriolus versicolor on the Total Phenol Contents and Antioxidant Properties on Black Soybean

Aim of this study was to evaluate the influence of solid-state fermentation of 4 strains ((Ganoderma oregonense (GO), Ganoderma lucidum (GL), Ganoderma sinensis (GS), and Coriolus versicolor (CV))) on the nutrients, functional ingredients, and antioxidant activity in black soybean. As a result, after fermentation by 3 strains of Ganoderma spp. and CV, the contents of crude protein, crude fat, reducing sugar, soluble protein, triterpenoid, and total phenol contents in black soybean significantly increased P < 0.01 , particularly in CV-black soybean. The contents of crude protein, crude fat, reducing sugar, soluble protein, and total phenol were 122.92%, 132.69%, 290.08%, 122.58%, and 142.47% higher than those of the control groups, respectively. But the total sugar and crude fiber contents decreased significantly P < 0.01 . Furthermore, analysis of antioxidant capacity showed that all the fermented products had scavenging effects on DPPH, hydroxyl, and superoxide anion radicals. In addition, the DPPH scavenging ability of CV fermented products was highest, the hydroxyl radical scavenging ability of GS fermented products was highest, and the superoxide anion radical scavenging ability of GO fermented products was highest, which were 9.43, 7.65, and 3.39 folds higher than those of control groups, respectively. All results evidenced that the fermented strains and the fermented time had remarkable influences on the nutritional ingredient and antioxidant activity of fermented products in black soybean. Also, there was a significant correlation between total phenolic content and antioxidant activities. In conclusion, fermented black soybean with fungus has the potential to be developed into a functional food and nutraceutical material.

Production of Foxtail-Millet-Based Composite Antioxidant Nutritive Flour Using Coarse Grains and Fruit Flour

Antioxidants are primarily responsible for the beneficial health effects of foxtail millet. This study evaluated a foxtail-millet-based composite antioxidant nutritive flour consisting of fermented foxtail millet, coarse grains, and fruit powders. The composition of the antioxidant nutritive flour was optimized, and it was found to be rich in antioxidant nutrients, such as phenolics (2.27 g/100 g), vitamin C (0.21 g/100 g), and polysaccharides (0.35 g/100 g). The results revealed that this composite nutritive flour has enhanced in vitro and in vivo physicochemical properties and higher antioxidant activities than commercial nutritive flour. The total antioxidant capability, superoxide dismutase (SOD) capability, and superoxide radical scavenging abilities were 0.84 mM Trolox equivalents/g, 38.29 U/g, and 42.02%, respectively. The activity of the antioxidant enzyme SOD and glutathione peroxidase increased, whereas malondialdehyde levels decreased in the liver, heart, and kidney of mice treated with the nutritive flour, indicating the potential antioxidant activity of this fermented foxtail-millet-based nutritive flour.

Multiple Bioactivities of Peptides from Hydrolyzed Misgurnus anguillicaudatus

Misgurnus anguillicaudatus (loach) is a widely distributed benthic fish in Asia. In this study, the alkaline protease was used to hydrolyze loach, and the hydrolysate products of different molecular weights were obtained by membrane separation. In vitro antioxidant assays showed that the <3 kDa fraction (SLH-1) exhibited the strongest antioxidant activity (DPPH, hydroxyl radical and superoxide radical scavenging ability, and reducing power), while SLH-1 was purified by gel filtration chromatography, and peptide sequences were identified by LC-MS/MS. A total of six peptides with antioxidant activity were identified, namely SERDPSNIKWGDAGAQ (D-1), TVDGPSGKLWR (D-2), NDHFVKL (D-3), AFRVPTP (D-4), DAGAGIAL (D-5), and VSVVDLTVR (D-6). In vitro angiotensin-converting enzyme (ACE) inhibition assay and pancreatic cholesterol esterase (CE) inhibition assay, peptide D-4 (IC50 95.07 μg/mL, 0.12 mM) and D-2 inhibited ACE, and peptide D-2 (IC50 3.19 mg/mL, 2.62 mM), D-3, and D-6 acted as pancreatic CE inhibitors. The inhibitory mechanisms of these peptides were investigated by molecular docking. The results showed that the peptides acted by binding to the key amino acids of the catalytic domain of enzymes. These results could provide the basis for the nutritional value and promote the type of healthy products from hydrolyzed loach.

Insight into Antioxidant Activity and Peptide Profile of Jinhua Ham Broth Peptides at Different Cooking Times.

This present study aimed to investigate the effects of various cooking times (1 h, 1.5 h, 2 h, 2.5 h, named as JHBP-1, JHBP-1.5, JHBP-2, JHBP-2.5) on the antioxidant activity and peptide profile of Jinhua ham broth peptides (JHBP). The peptides extracted from uncooked ham were used as an uncooked group with the name of JHBP-0. The results revealed that the antioxidant efficacy in the four cooked groups changed dramatically compared to JHBP-0. After cooking, the DPPH radical scavenging activity, hydroxyl radical scavenging activity and superoxide anion radical scavenging activity decreased, except for the Fe2+ chelation and ABTS+ scavenging capacity which increased significantly. However, the cooked groups still showed a strong antioxidant capacity. In particular, the superoxide anion radical scavenging ability and the Fe2+ chelation action were significantly stronger compared to glutathione (GSH) and butylated hydroxytoluene (BHT) (p < 0.05). JHBP-1.5 also displayed stronger antioxidant capacity than the other three cooked groups, and its secondary structure and mass distribution changed significantly after cooking, specifically with an increased proportion of helix and <1 kDa peptides. Moreover, the constitution of free amino acids (FAAs) and the types of peptides released in the broth increased significantly with a longer cooking time. In total, 1306 (JHBP-0), 1352 (JHBP-1), 1431 (JHBP-1.5), 1500 (JHBP-2), and 1556 (JHBP-2.5) peptide sequences were detected using LC-MC/MC. The proportion of <1 kDa peptides also gradually increased as the cooking time extended, which is consistent with the molecular weight distribution measurements.

Enhanced Yield of Bioactive Compounds and Antioxidant Activities in Four Fermented Beans of Phellinus linteus Strains (Agaricomycetes) by Solid-State Fermentation.

Phellinus linteus is a famous medicinal mushroom which exhibits various biological activities. This study aimed to investigate the effects of solid-state fermentation by Ph. linteus on the yield of bioactive compounds and antioxidant activities of beans. Four bean substrates were prepared and inoculated with inoculum of three strains of Ph. linteus, respectively. During the cultivation, the harvested samples were dried, grounded, extracted, and determined the contents of bioactive compounds and antioxidant activities. The results indicated that the mung bean fermented by Ph. linteus 04 had the highest polysaccharide content (98.8 mg/g). The highest total phenolic and flavonoid contents were in fermented soybeans by Ph. linteus 03 (15.03 mg gallic acid equivalents/g and 63.24 mg rutin equivalents/g, respectively). The 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activities of hot water extracts were higher than those of ethanolic extracts for fermented beans by three Ph. linteus strains. However, the superoxide anion radical scavenging ability of ethanolic extracts was higher than those of hot water extracts in the fermented beans of the three strains. The ferrous ion (Fe2+)-chelating abilities of hot water extracts were higher than those of ethanolic extracts in fermented beans by Ph. linteus 03 and 04. In contrast, ethanolic extracts were higher than hot water extracts in fermented beans by Ph. linteus 06. Overall, these results indicate that the fermentation by Ph. linteus strains increased the bioactive compounds and antioxidant activities of four beans.

Exopolymer-Functionalized Nanoselenium from Bacillus subtilis SR41: Characterization, Monosaccharide Analysis and Free Radical Scavenging Ability.

To provide a safe and effective supplement of the essential trace element selenium, we focused on the biosynthesis of nanoselenium (SeNPs) via probiotics. A novel kind of exopolymer-functionalized nanoselenium (SeEPS), whose average size was 67.0 ± 0.6 nm, was produced by Bacillus subtilis SR41, whereas the control consisted of exopolymers without selenium (EPS). Chemical composition analysis, Fourier transform infrared (FTIR) spectroscopy and high-performance liquid chromatography (HPLC) confirmed that SeEPS and EPS shared similar polysaccharide characteristic groups, such as COO- and C=O, and contained not only 45.2–45.4% of sugars but also 23.5–24.7% of proteins and some lipids. Both SeEPS and EPS were primarily composed of mannose, amino glucose, ribose, glucose and galactose. Furthermore, to identify the biologically active component of SeEPS, three kinds of selenium particles with different stabilizers [Se(0), bovine serum albumin-Se and EPS-Se] were synthesized chemically, and their ability to scavenge free radicals in vitro was compared with that of SeEPS and EPS. The results revealed that EPS itself exhibited weak superoxide and hydroxyl radical scavenging abilities. Nevertheless, SeEPS had superior antioxidant properties compared to all other products, possibly due to the specific structure of SeNPs and exopolymers. Our results suggested that exopolymer-functionalized SeNPs with specific monosaccharide composition and structure could eventually find a potential application as an antioxidant.

Structural Characteristics, Antioxidant, and Immunostimulatory Activities of an Acidic Polysaccharide from Raspberry Pulp.

The extraction and characterization of new bioactive plant-derived polysaccharides with the potential for use as functional foods and medicine have attracted much attention. In the present study, A novel acidic polysaccharide (RPP-3a) with a weight-average molecular weight (Mw) of 88,997 Da was isolated from the raspberry pulp. RPP-3a was composed of rhamnose, arabinose, galactose, glucose, mannose, and galacturonic acid at a molar ratio of 13.1:28.6:16.8:1.4:6.2:33.9. Structural analysis suggested that the RPP-3a backbone was composed of repeating units of →4)-β-Galp-(1→3,4)-α-Rhap-(1→[4)-α-GalAp-(1→4)-α-GalAp-(1→]n with branches at the C-4 position of rhamnose. The side chain of RPP-3a, containing two branch levels, was comprised of α-Araf-(1→, →5)-α-Araf-(1→, →3,5)-α-Araf-(1→, →3)-β-Galp-(1→, →3,6)-β-Galp-(1→, →4)-β-Glcp-(1→, and →2,6)-α-Manp-1→ residues. RPP-3a exhibited moderate reducing power and strong hydroxyl and superoxide anion radical scavenging abilities. RPP-3a significantly promoted the viability of RAW264.7 macrophages by increasing the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) at both the expression and transcriptional levels. In summary, the immunostimulatory and antioxidant activities make RPP-3a a viable candidate as a health-beneficial functional dietary supplement.

Antihypertensive and In Silico Docking Studies OF Phytoconstituents Isolated from Syzygium Alternifolium Bark

Aim of the Study: Pharmacological examination was done for methanolic extract Syzygium alternifolium bark (MESA) for its antihypertensive activity, Angiotensin converting enzyme (ACE) inhibition by in vitro and in vivo studies, antioxidant activity via radical scavenging activity.&#x0D; Methods: Albino Wistar rats were allowed to treat with dexamethasone (30 μg/kg/day s.c) or saline for about 14 days. Methanolic extract of Syzygium alternifolium (300 mg/kg, b.w., p.o.) is administered from day 8 to 14 day of study to the treatment group. Chronic fructose treatment in rats showed to increase blood pressure in relationship with insulin blockade. MESA (300 mg/kg b.w, p.o) was capable of preventing the origin of hypertension by diminishing the raised blood levels i.e., blood pressure.&#x0D; Results and Discussion: The decrease in the blood pressure is accredited to the restraint of ACE. The preliminary phytochemical examination suggests that the MESA has alkaloids, flavonoids, glycosides, steroids, sugars, proteins and tannins. MESA exhibited 1, 1-diphenyl-2-picrylhydrazyl interrupting radical chain reactions with IC50 value of 12.34 µg/ml just as superoxide radical scavenging ability with IC50 value of 21 µg/ml. MESA showed antihypertensive activity by limiting angiotensin converting enzyme and interrupted free radical reactions i.e., antioxidant property. These findings reveal the existence of probable active constituents of MESA. Understanding the molecular method of activity of natural product is a vital stage for creating drugs from them. The docking studies of the number of compounds were performed using mCule software. The constituents have good binding ability with ACE 1 inhibitor, Calcium channel blocker, and Renin inhibitor proteins and Ramachandran plot is analyzed.&#x0D; Conclusion: The compounds from Syzygium alternifolium bark have shown antihypertensive activity when compared with standard drug Amlodipine.

Amino acid composition, mineral profile, free radical scavenging ability, and carbohydrase inhibitory properties of Moringa oleifera seed globulin, hydrolysates, and membrane fractions.

The nutritional-amino acid profile and mineral element of Moringa oleifera seed globulin (GLO) and its hydrolysates as well as the in vitro bioactive properties-antioxidant, alpha-amylase, and alpha-glucosidase inhibition of the GLO, hydrolysates, and membrane fractions were reported. The results showed that M. oleifera contained significant amounts of essential amino acids (EAA), which are more than the minimum required by the Food and Agricultural Organization for children, except for tryptophan, which was the limiting amino acid. However, hydrolysis mostly led to a reduction in the contents of the EAA. While the process of hydrolysis and the subsequent membrane fractionation produced peptides with improved activities in 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid radical scavenging ability and oxygen radical absorbance capacity, this process produced no activities in superoxide radical scavenging ability, α-amylase, and α-glucosidase inhibitory potentials of some of the hydrolysates and peptides fractions. In summary, M. oleifera seed peptide fraction (<3kDa) from the alcalase-derived hydrolysate contains potent antioxidants but relatively low in vitro antidiabetic properties. PRACTICAL APPLICATIONS: Several studies have established the ability of proteins, including hydrolysate and peptide fractions to provide some bioactive properties such as antioxidant, antidiabetic, anti-inflammatory among others. However, because protein functionalities are influenced by several factors such as the source, type, processing method employed among others, research has continued to evaluate the bioactivities of proteins under different conditions. In this study, therefore, we reported the impact of processing methods (hydrolysis, enzyme type, and peptide size) on the nutritional, antioxidant, and in vitro antidiabetic properties of M. oleifera seed globulin, its hydrolysates, and membrane fractions. This information plays an important role in the further exploitation of M. oleifera seed proteins in the development of functional foods and nutraceuticals.

Antioxidant and anti-tyrosinase activity of a novel stilbene analogue as an anti-browning agent.

Tyrosinase inhibitors find potential application in food, cosmetic and medicinal products, but most of the identified tyrosinase inhibitors are not suitable for practical use because of safety regulations or other problems. For the purpose of development of novel tyrosinase inhibitors that meet the requirement for practical application, a novel stilbene analogue (SA) was designed. SA was found to possess a potent inhibitory effect against both mono- and diphenolase activities of mushroom tyrosinase, with IC50 values of 1.56 and 7.15 μmol L-1 , respectively. Compared with a natural tyrosinase inhibitor - kojic acid - the anti-tyrosinase effect of SA was significantly improved. Analysis of inhibition kinetics indicated that SA was a reversible and competitive-noncompetitive mixed-type inhibitor. SA was also found to possess more potent antioxidant activities (DPPH, superoxide anion radical and hydroxyl radical scavenging ability) than those of kojic acid. Cell viability studies revealed that SA was non-toxic to two cell lines. Furthermore, an anti-browning test demonstrated that SA effectively delayed the blackening of shrimp. SA has potential as an anti-browning agent in foods. © 2021 Society of Chemical Industry.

Facile synthesis, characterization, antioxidant activity, and antibacterial activity of carboxymethyl inulin salt derivatives

A series of novel carboxymethyl inulin derivatives bearing thiosemicarbazide salts, aminoguanidine salts, and aniline salts were prepared via a facile method and employed to evaluate in vitro antioxidant activity and antibacterial activity. Their structures were characterized by Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The characterization results confirmed the successful synthesis of carboxymethyl inulin salt derivatives. The in vitro antioxidant activity evaluation results presented a significant improved superoxide radical scavenging ability, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, and reducing ability of carboxymethyl inulin salt derivatives as compared to inulin and carboxymethyl inulin. In particular, the series of carboxymethyl inulin derivatives containing thiosemicarbazide salts and aminoguanidine salts showed remarkable free radical scavenging ability and reducing ability. Moreover, the carboxymethyl inulin derivatives containing thiosemicarbazide salts and aniline salts displayed potential antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria. The cytotoxicity assay was also carried out on L929 cells by CCK-8 method, and all samples showed weak cytotoxicity. Furthermore, hemolysis results showed no hemolytic activity of most prepared inulin derivatives. In summary, the inulin derivatives containing thiosemicarbazide salts exhibited outstanding antioxidant activity, antibacterial activity, and biocompatibility, and the all-inclusive properties highlighted their potential use in food and medical applications.

Effects of Lactobacillus plantarum Fermentation on the Chemical Structure and Antioxidant Activity of Polysaccharides from Bulbs of Lanzhou Lily.

Recently, Lanzhou lily has attracted more attention because of its bioactive components specifically polysaccharides. We studied in vitro the effects of Lactobacillus plantarum fermentation on the physicochemical properties, chemical structure, and antioxidant activity of the Lanzhou lily polysaccharide. The results showed that compared with the unfermented Lanzhou lily polysaccharide (LP-W), the molecular weight (Mw) of the fermented Lanzhou lily polysaccharide (LPF-W) decreased from 4334 to 1684 kDa, the particle size decreased from 300.8 ± 6.38 to 141.9 ± 4.96 nm, and the solubility increased from 72.33 ± 3.58 to 104.27 ± 2.91 mg/mL. In addition, after fermentation, the monosaccharide composition of LPF-W changed, and the alternation of mannose residues and glucose residues disappeared. The results of the analysis of the antioxidant activity in vitro showed that compared with LP-W, the fermented LPF-W had higher DPPH radical ability, superoxide anion radical scavenging ability, and reducing efficiency, but the hydroxyl radical scavenging ability decreased. These findings provide a reference for the potential application of the lily polysaccharide as a plant-derived antioxidant in functional foods.

Fungicide Difenoconazole Induced Biochemical and Developmental Toxicity in Wheat (Triticum aestivum L.).

Difenoconazole is one of the most commonly used fungicides to prevent and treat plant diseases caused by certain fungi. Due to increasing usage, more difenoconazole has been released into the environment and caused environment pollution. However, the potential impact of difenoconazole on plant growth and development and its involved mechanism are unclear. In this study, we discovered that difenoconazole exposure significantly inhibited plant growth, evidenced by the decrease in root dry weight, total root length, and surface area by 20–70%, 43–73%, and 26–66%, respectively, under different regimes of treatment concentrations and periods. Difenoconazole exposure also significantly inhibited shoot growth and development by decreasing 33–61% of the shoot dry weight and 50–65% of the leaf area. Difenoconazole exposure induced plant leaf cells to generate more ROS (O2•− and H2O2) and MDA, which resulted in a decreased chlorophyll content and then inhibited leaf photosynthesis. Difenoconazole exposure also induced the activities of superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (G-POD), and ascorbate peroxidase (APX) in the roots and leaves of the wheat seedlings. SOD and APX activities were higher and more stable in the roots than those in the leaves. Based on our study, plant roots exhibited a more pronounced superoxide radical scavenging ability than plant leaves. In summary, difenoconazole exposure caused oxidative stress, reduced chlorophyll biosynthesis and functions, and then inhibited wheat plant growth and development.

Electrophilic Modulation of the Superoxide Anion Radical Scavenging Ability of Copper(II) Complexes with 4-Methyl Imidazole.

Three Cu(II) coordination compounds with 4-methyl imidazole were obtained, such as [Cu(C4H6N2)4(NO3)2], [Cu(C4H6N2)4Br2], and [Cu(C4H6N2)4Cl2]. Crystallographic studies confirmed their structural similarity with Cu(II) in the active site of endogenous copper-zinc superoxide dismutase (CuZn-SOD). The superoxide anion radical (O2•-) scavenging activity was evaluated by the non-enzymatic experimental assay and followed the trend [Cu(C4H6N2)4(NO3)2] > [Cu(C4H6N2)4Br2] > [Cu(C4H6N2)4Cl2]. The density functional theory and the hard and soft acids and bases principle showed the importance of the electron-deficient character of Cu(II) in the chemical reactivity of the coordination compounds; Cu(II) is the softest site in the molecule and it is preferred for the nucleophilic and radical attacks of the soft O2•-. A simple rule was obtained: "the electron-deficient character of Cu(II) is the key index for the O2•- scavenging activity and is modulated by the electron-releasing counteranion effect on the coordination compound".

The study on the antioxidant activity of polysaccharides isolated from Polygonatum odoratum (Mill.) Druce

The polysaccharides isolated from Polygonatum odoratum (Mill.) Druce (POPs) by water extraction, after precipitation with ethanol were purified through deproteinization, decolorization, dialysis, and column chromatography leading to a purified polysaccharide (POPs-I) content of 90.7 %. The scavenging of oxygen free radicals and inhibition of lipid peroxidation (LPO) by POPs-I were analyzed using a colorimetric method. The results showed that the hydroxyl radical scavenging ability of the polysaccharides was weaker than that of benzoic acid, but stronger than those of ascorbic acid and mannitol, and that the superoxide anion radical scavenging ability was inferior to those of all three. When the concentration was higher than 1.0 mg/mL, the POPs-I could inhibit LPO by superoxide anion radicals to a certain degree. Therefore, this work suggests that POPs-I are potential antioxidant agents in medicine and functional food.

Low Molecular Weight Fucoidan from Saccharina Japonica Ameliorates the Antioxidant Capacity and Reduces Plaque Areas in Aorta in Apoe-Deficient Mice with Atherosclerosis

Low molecular weight fucoidan (LMWF) extracted from Saccharina japonica exhibits many biological activities including immune regulation and inhibition of tumor angiogenesis, but little research has been done for its antioxidant effect in atherosclerosis (AS). In this study, AS modeling was successfully conducted in ApoE-/- mice by feeding atherogenic diet to animals. The antioxidant activity of LMWF was verified by determining its superoxide anion radical scavenging ability and hydroxyl radical scavenging ability. LMWF significantly increased the antioxidant capacity of AS mice, this conclusion being confirmed by total antioxidant capacity (T-AOC) assay. Test results confirmed that LMWF can enhance T-AOC by reducing reactive oxygen species (ROS) and oxidized low density lipoprotein (ox-LDL) levels and increasing glutathione peroxidase (GSH-Px) level in myocardium and liver tissues of AS mice. The results showed that LMWF and probucol had comparable antioxidant effects on AS, and when combined, no further antioxidant effect was achieved.

Optimization of fermentation of Fomes fomentarius extracellular polysaccharide and antioxidation of derivatized polysaccharides

Fermentation is a metabolic process that converts sugars into acids, gases, or alcohol. This process occurs in yeasts and bacteria, as well as in muscle cells when faced with a lack of oxygen. In this paper, isolation, culture, purification and extracellular polysaccharides of strain Fomes fomentarius were studied. Extraction of polysaccharides from a culture based on F. fomentarius extracellular polysaccharides, extracellular polysaccharides fermentation experiments was optimized and compared, the optimal fermentation method was obtained; extracellular polysaccharides were sulfated, phosphorylated experiments, selenium acidified, discussed the preparation of derivative polysaccharides and microscopic detection, and finally studied extracellular polysaccharides on DPPH, The scavenging ability, superoxide anion radical and hydroxyl radical scavenging ability of the derived polysaccharides were compared. The results showed that the extracellular polysaccharide and derivatized polysaccharide of F. fomentarius had certain antioxidant activity.

Physiochemical, rheological, microstructural, and antioxidant properties of yogurt using monk fruit extract as a sweetener

A yogurt using monk fruit extract (MFE) as a sweetener was developed. The aim of the study was to investigate the viability of using MFE to develop sweetened yogurts without the calories of added sugar. The physiochemical, rheological, microstructural, and antioxidant properties of yogurt were studied. Rheological results showed that MFE affected the yogurt fermentation process and its rheological properties. Yogurt sweetened with MFE had similar microstructural properties to yogurt sweetened with sucrose. Yogurt with MFE showed higher levels of gly-pro-p-nitroanilide and dipeptidyl peptidase IV inhibitory activities, 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity, α-glucosidase inhibitory activities, and superoxide anion radical scavenging ability compared with other yogurt samples. Results indicated that MFE could be a novel sweetener and a food antioxidant for functional yogurt and related products.

Synthesis and Characterization of Inulin Butyrate Ester, and Evaluation of Its Antioxidant Activity and In Vitro Effect on SCFA Production

AbstractThe aim of this study is to develop a method for the synthesis of inulin butyrate ester (IBE) as a short chain fatty acid (SCFA) delivery carrier. Inulin is modified by butyric anhydride and the structure is characterized by Fourier Transform Infrared and 1H NMR. On this basis, the synthetic conditions are optimized with response surface methodology (RSM) to investigate the effects of three parameters (the ratio of anhydride to inulin, inulin concentration, and reaction temperature) on the degree of substitution (DS). Under the optimal conditions, the actual experimental DS is 2.59 ± 0.14. The antioxidant activities of inulin and IBE are determined by superoxide anion radical and hydroxyl radical scavenging ability. The results show that the butyrylation inulin increases antioxidant activities and indicate that IBE could be used as a potential antioxidant. In a 36 h in vitro fermentation experiment, IBE is shown to increase the total SCFA content and the butyrate ratio, which illustrates that IBE could be used as SCFA carrier for delivering high concentration of SCFA to the colon, and thus influencing intestinal health.