Hydroxyl Radical Scavenging Capacity Research Articles

Deer Skin Collagen Peptides Bound to Calcium: In Vitro Gastrointestinal Simulation of Digestion, Cellular Uptake and Analysis of Antioxidant Activity

The by-product of deer skin, which has mostly been used as a decorative material, is rich in collagen and amino acids that could bind to Ca2+. Therefore, the preparation process, stability, antioxidant activity and calcium transport capacity of deer skin collagen peptide calcium chelate (Ca-DSCP) were investigated. In addition, the structure of the new chelate was characterized. The preparation process of Ca-DSCP was optimized using one-way experiments and response surface methodology. The ideal conditions were pH 9, 48 °C, and a peptide-to-calcium mass ratio of 5:1. The chelation rate was (60.73 ± 1.54)%. Zeta potential, XRD, UV–vis and FTIR analyses yielded that deer skin collagen peptides (DSCP) underwent a chelating reaction with calcium ions to form new structures. The stability of Ca-DSCP and the fraction of bioavailability of calcium ions were determined using in vitro gastrointestinal digestion and a Caco-2 cell monolayer model. The results showed that fraction of bioavailability and stability of DSCP were improved by influencing the structural characterization. The antioxidant activities of DSCP and Ca-DSCP were evaluated by measuring relevant oxidative stress indicators, DPPH radical scavenging capacity and hydroxyl radical scavenging capacity. Finally, bioinformatics and molecular docking techniques were utilized to screen and study the antioxidant mechanism of DSCP.

Laminarin-modulated osmium nanozymes with high substrate-affinity and selective peroxidase-like behavior engineered colorimetric assay for hydroxyl radical scavenging capacity estimation.

Hydroxyl radical (·OH) scavenging capacity (HOSC) estimation is essential for evaluating antioxidants, natural extracts, or drugs against clinical diseases. While nanozymes offer advantages in related applications, they still face limitations in activity and selectivity. In response, this work showcases the fabrication of laminarin-modulated osmium (laminarin-Os) nanoclusters (1.45 ± 0.05nm), functioning as peroxidase-like nanozymes within a colorimetric assay tailored for rational HOSC estimation. This study validates both the characterization and remarkable stability of laminarin-Os. By leveraging the abundant surface negative charges of laminarin-Os and the surface hydroxyls of laminarin, oxidation reactions are facilitated, augmenting laminarin-Os's affinity for 3,3',5,5'-tetramethylbenzidine (TMB) (KM = 0.04mM). This enables the laminarin-Os-based colorimetric assay to respondto·OH more effectively than citrate-, albumin-, or other polysaccharides-based Os. In addition, experimental results also validate the selective peroxidase-like behavior of laminarin-Os under acidic conditions. Antioxidants like ascorbic acid, glutathione, tannic acid, and cysteine inhibit absorbance at 652nm in the colorimetric platform using laminarin-Os's peroxidase-like activity. Comparedwithcommercial kits, this assay demonstrates superior sensitivity (e.g., responds to ascorbic acid 0.01-0.075mM, glutathione 1-15µg/mL, tannic acid 0.5-5µM, and monoammonium glycyrrhizinate cysteine 1.06-10.63µM) and HOSC testing for glutathione, tannic acid, and monoammonium glycyrrhizinate cysteine. Overall, this study introduces a novel Os nanozyme with exceptional TMB affinity and ·OH selectivity, paving the way for HOSC estimation in biomedical research, pharmaceutical analysis, drug quality control, and beyond.

Fingerprint profiling for quality evaluation and the related biological activity analysis of polysaccharides from Liuweizhiji Gegen-Sangshen beverage.

Liuweizhiji Gegen-Sangshen beverage (LGS) is popular in China, which has been used for alleviating alcohol-mediated discomfort and preventing alcoholic liver disease (ALD). This beverage is consisted of six herbal components that are known as functional foods and fruits. LGS is rich in polysaccharides, however, the activity and quality evaluation of LGS-derived polysaccharides remain unexplored. The purpose of this study is thus to establish a comprehensive quality control methodology for the assessment of LGS polysaccharides (LGSP) and to further explore the anti-oxidant, anti-inflammatory as well as prebiotic effect of LGSP. LGSP was extracted, followed by analysis of molecular weight distribution, monosaccharide content and structural characterization via integrating the application of high-performance size exclusion chromatography (HPSEC), 1-phenyl-3-methyl-5-pyrazolone-HPLC (PMP-HPLC), fourier transform infrared spectroscopy (FT-IR) as well as nuclear magnetic resonance spectroscopy (NMR) techniques. The anti-oxidation activity of LGSP was determined by DPPH, ABTS, hydroxyl radical scavenging capacity and total antioxidant capacity. The anti-inflammation of LGSP were assessed on the RAW 264.7 cells. The effect of LGSP on growth of Lactobacillus, Bifidobacterium bifidum and Bifidobacterium adolescentis was evaluated. The results demonstrated that LGSP had two molecular weight distribution peaks, with the average molecular weights of (6.569 ± 0.12) × 104 Da and (4.641 ± 0.30) × 104 Da. LGSP was composed of 8 monosaccharides, with galacturonic acid, glucose rhamnose and galactose representing the highest molar ratios. Homogalacturonic acid (HG) type and rhamnosegalacturonic acid glycans I (RG-I) type and α-1,4-glucan were present in LGSP. LGSP concentration in LGS was 17.94 ± 0.28 mg/mL. Furthermore, fingerprint analysis combined with composition quantification of 10 batches of LGSP demonstrated that there was a high similarity among batches. Notably, LGSP exhibited anti-oxidant effect and inhibited expressions of pro-inflammatory factors (TNF-α and IL-6) in LPS-stimulated RAW 264.7 cells. In addition, LGSP remarkably promoted the proliferation of probiotics Lactobacillus, Bifidobacterium bifidum and Bifidobacterium adolescentis, showing good prebiotic activity. The results of present study would be of help to gain the understanding of structure-activity relationship of LGSP, provide a reference for quality evaluation of bioactive LGSP, and facilitate development of unique health and functional products in the future.

Ulvans, sulfated β-d-galactans and xyloarabinogalactan: A comparative approach to extraction, structural characterization and antioxidant activity assessment

Antioxidants can be extracted from various seaweeds as natural ingredients for use in foods, cosmetics, and pharmaceuticals. The composition and structure of polysaccharides extracted from four green seaweeds: Ulva lactuca (UL), Halimeda opuntia (HO), Caulerpa racemosa (CR) and Chaetomorpha antennina (CA) were correlated with their antioxidant activities. Crude extracts were characterized by NMR (1H and 13C), HP-SEC, HPAEC-PAD and FTIR spectroscopy. Extracted polysaccharides were assayed spectrophotometrically for their total sugar, sulfate, phenolic and protein contents. The antioxidant capacities of each fractionated polysaccharide sample were evaluated by five methods, i.e., ABTS (2,2-azino-bis-[3-ethylbenzothiazoline-6-sulfonic acid]), DPPH (2,2-diphenyl-1-picrylhydrazyl radical), ferric-reducing power in FRAP (Ferric-reducing Antioxidant Power), superoxide dismutase (SOD), and the hydroxyl radical (OH) scavenging capacity assay. All polysaccharides had molecular weights (MW) under 1000 kDa, with HO having the lowest MW (<100 kDa). Polysaccharide extracts of UL (i.e., l-iduronic acid, 1,4-linked α-l-rhamnose, β-d-glucuronic acid) and CA were promising sources of antioxidants. The highest antioxidant capacity was measured in extracts from CA-2B (52.1 ± 0.9 μg/mL) using the ABTS assay, while CR-1B exhibited the highest antioxidant activity in both the FRAP (303.7 ± 8.2 μm/mL) and OH (28.4 ± 0.8%) assays. Taken together, useful insights were gained into the potential health benefits of selected green seaweed polysaccharides (i.e., ulvans, sulfated or/and pyruvylated β-d-galactans and sulfated xyloarabinogalactan) for applications in the pharmaceutical, food and biotechnology industries.

Study on the total flavonoid content and antioxidant activity of Morus nigra Linn. from different origins in Xinjiang

Optimization of the extraction process of total flavonoids from Morus nigra Linn. based on response surface design, to compare the differences in total flavonoid content of Morus nigra Linn. from different origins in Xinjiang and its relationship with antioxidant activity. A one-way test was used to investigate the effects of ethanol volume fraction, material-liquid ratio, ultrasonic power and ultrasonic time on total flavonoid content analysis of Morus nigra Linn. , Box-Behnken response surface design optimisation was used to derive the optimal extraction process parameters. Meanwhile, the in vitro antioxidant activity of Morus nigra Linn. was evaluated by antioxidant activity indexes such as hydroxyl radical scavenging capacity and ferric ion reducing capacity. The optimal extraction condition was 45% ethanol by volume, 1∶20 g/mL material-liquid ratio, 300W ultrasound power and 60 min ultrasound time. The total flavonoid content of Morus nigra Linn. s from six origins was detected and the result showed that Kuche &gt;Kashgar &gt;Kuche Wuqia Town&gt;Hetian &gt;Ying jisha &gt;Yutian, in which the total flavonoid content of mulberry in Kucha city was(27.159±0.091)mg/g. The difference in the total flavonoid content of Morus nigra Linn. s in different origicns was statistically significant(P&lt;0.05). In vitro antioxidant activity analysis showed that the antioxidant activity of mulberry from Kuche and Hetian was stronger, and the hydroxyl radical scavenging capacity, ferric ion reducing capacity, and total antioxidant capacity of mulberry from various origins were statistically significant(P&lt;0.05). The correlation analysis showed that the total flavonoid content of Morus nigra Linn. was correlated with the antioxidant capacity to improve the scavenging of hydroxyl radicals. The ultrasonic-assisted method of extracting total flavonoids from Morus nigra Linn. is simple, and the model constructed has a high degree of fit, which can better compare the total flavonoids content of Morus nigra Linn. from different origins in Xinjiang.

Relationship among EPR oxidative stability and spectrophotometric parameters connected to antioxidant activity in beer samples

A relationship between EPR and spectrophotometric parameters related to beer staling and antioxidant activity, was identified. AUC (area under the curve), intensity at 150 min (T150), radical scavenging activity (RSA), total phenolic compounds (TPC), hydroxyl radical scavenging capacity (HRSC) and one parameter linked to staling degree of beers (thiobarbituric index, TBI) were related. Temperature was modified to find the proper working conditions for EPR spin-trapping experiments and it was found that it affected the kinetic of PBN adduct evolution. For the samples reaching a maximum intensity signal, the higher the heating temperature, the shorter the time interval needed to reach it. No linear relationship was detected among parameters obtained with EPR spin trapping experiments and RSA, TPC, TPI, and HRSC when correlating one parameter with another. On the contrary, a good linear relationship was found among AUC or T150 and a combination of RSA, TPC, TPI, and HRSC (R2 = 0.9562 and 0.9694, respectively). The goodness of fit increased to R2 = 1 when a combination of AUC and T150 was related to a combination of RSA, TPC, and TPI, and HRSC.

Variation of the Content and Antioxidant Activity of Active Substances in the Kombucha Fermentation of Mulberry Leaves

With the increasing emphasis on healthy living, Kombucha beverages are becoming more and more popular. Recently, fermented Kombucha with different materials and investigated the efficacy have become hot topics. In this paper, mulberry leaves were used as substrates for Kombucha fermentation. The active substances contents and antioxidant activities of the fermented mulberry leaf infusion were significantly enhanced. After being fermented for 10 days, the total phenolic substances and total flavonoids in the Kombucha fermented mulberry leaf infusion were 7.38 and 12.24 times higher than those in the unfermented mulberry leaf infusion, respectively. While the mulberry leaf infusion that fermented for 6 days had the highest antioxidant capacity. The Ferric (Fe3+) reducing power, ABTS+ radical scavenging capacity, and hydroxyl radical (·OH) scavenging capacity were enhanced by 90.3%, 21.82%, and 46.2%, respectively. In conclusion, after being fermented by Kombucha, the antioxidant properties of mulberry leaf infusion were significantly improved, which will contribute to expanding the subsequent development and application of mulberry leaf.

Preparation and identification of antioxidant peptides from Quasipaa spinosa skin through two-step enzymatic hydrolysis and molecular simulation

Frog skin, a by-product of Quasipaa Spinosa farming, is rich in protein and potentially a valuable raw material for obtaining antioxidant peptides. This study used papain combined with acid protease to digest frog skin in a two-step enzymatic hydrolysis method. Based on a single factor and response surface experiments, experimental conditions were optimized, and the degree of hydrolysis was 30 %. A frog skin hydrolysate (QSPH-Ⅰ-3) was obtained following ultrafiltration and gel filtration chromatography. IC50 for DPPH, ABTS, and hydroxyl radical scavenging capacities were 1.68 ± 0.05, 1.20 ± 0.14 and 1.55 ± 0.11 mg/mL, respectively. Peptide sequences (17) were analyzed and, through molecular docking, peptides with low binding energies for KEAP1 were identified, which might affect the NRF2-KEAP1 pathway. These findings suggest protein hydrolysates and antioxidant peptide derivatives might be used in functional foods.

Ultrasound-assisted enzymatic extraction of polysaccharides from Paulownia flowers: process optimization, structural characterization, antioxidant and hypoglycemic activities

This study aimed to optimize the ultrasound-assisted enzymatic extraction (UAEE) process of Paulownia flowers polysaccharides (PFP) and investigate its antioxidant and hypoglycemic activities. The optimal extraction conditions were cellulase dosage 1.6 mg/g, liquid-solid ratio 27:1mL/g, ultrasonic power 230 W, temperature 51 °C, the PFP yield reached 5.50 % which was close to the predicted value of 5.59 %. Furthermore, the PFP was isolated and purified by DEAE-52 cellulose column and sephadex G-200 column to obtain two polysaccharide fractions, PFP1-1 and PFP2-1. The characteristics, antioxidant activity and hypoglycemic activity of PFP1-1 and PFP2-1 were analyzed. PFP1-1 with a molecular weight of 52.8 kDa was mainly composed of mannose and glucose (molar ratio1.00:5.05), and PFP2-1 with a molecular weight of 8.768 kDa was consisted of mannose, rhamnose, glucuronic acid, glucose (molar ratio 1.00:7.41:8.09:11.30). Compared to PFP1-1, the antioxidant activity assays showed that PFP2-1 exhibited stronger DPPH radical, hydroxyl radical and superoxide radical scavenging capacity and the inhibitory activities revealed that PFP2-1 could more effectively inhibit α-amylase and α-glucosidase, which might be attributed to the uronic acid and low molecular weight in PFP2-1. This work will provide a foundation for the efficient extraction of PFP and utilization for antioxidant agent and digestive enzymes inhibitor of diabetes.

Evaluation of the functional properties of ethanolic and polysaccharide extracts of Spirulinaplatensis

This study aimed to investigate the prebiotic, antioxidant and antimicrobial activity of ethanolic and polysaccharide extracts from Spirulina platensis. The ethanol extract was obtained by the soxhlet method and the polysaccharide was extracted with hot water. Total phenol content was obtained by the folin-ciocalteu method. The ethanol extract and the polysaccharide extracted from the S. platensis had a high phenol. Also, the extract had comparable prebiotic properties with commercial prebiotic (Inulin). Both extracts in the period of 24–72 h affected the growth and viability of the Lactobacillus plantarum A7. Based on the results, the half-maximal inhibitory concentration (IC50) of DPPH free radical for ethanol extract and polysaccharide was estimated to be 0.279 and 0.319 mg/mL. Also, the IC50 of hydroxyl radical scavenging capacity for polysaccharide and ethanol extract was calculated to be 0.167, 0.14 mg/mL, respectively. Therefore, these compounds can be introduced as natural substances with antioxidant, prebiotic and antimicrobial capabilities in the food and pharmaceutical industries.

Assessing the Antioxidant Properties, In Vitro Cytotoxicity and Antitumoral Effects of Polyphenol-Rich Perilla leaves Extracts.

(1) Background: This study aimed to outline the antioxidant, antitumoral, and cytotoxic proprieties of various types of Perilla frutescens extracts obtained from the leaves of the species. (2) Methods: We determined total polyphenols, flavonoids and anthocyanins contents, as well as the in vitro antioxidant, antitumoral, and cytotoxic actions in three types of ethanolic extracts (E1, E2, E3) and in three types of acetone: ethanol extracts (A1, A2, A3) of Perilla frutescens according to standardized procedures. (3) Results: We found that Perilla frutescens ethanolic extracts had the highest total phenol and anthocyanins concentrations. The flavonoids concentration was not statistically different between the extracts. The iron chelating capacity, hydroxyl radical scavenging capacity, superoxide anion radical scavenging capacity, and lipoxygenase inhibition capacity showed a significant increase with higher concentrations of Perilla frutescens extracts, particularly the ethanolic extracts. Perillyl alcohol had greater cytotoxic capacity in the MG-63 cell line and E1 extract showed similar significant cytotoxic effects in the A431 cell line. (4) Conclusions: Both ethanolic and acetone-ethanol extracts from Perilla frutescens exhibited important antioxidant and antitumoral actions in vitro, which proportionally increased with concentration. The cytotoxic threshold determined in this study for various types of extracts could help determine the best dosage with the maximum antioxidant and antitumoral potential. Our results could serve as a basis for further studies that will investigate the cytotoxic effects of Perilla frutescens variants on various types of cancer cell lines.

Separation and antioxidant activities of new acetylated EGCG compounds

Acetylation could improve the bioavailability of (-)-Epigallocatechin-3-Gallate (EGCG), but the relationship of substitution degree and antioxidant capacity of acetylated EGCG was unclear. The acetylated EGCG products were separated by preparation high performance liquid chromatography (HPLC). Two mono substituted acetylated EGCG, three substituted acetylated EGCG (T-AcE), eight substituted acetylated EGCG (E-AcE) and (-)-Epigallocatechin gallate (EGCG) were isolated. The 7-acetyl-EGCG (S7-ACEGCG) and 7-acetyl-EGCG (T-AcE) were identified for the first time. The antioxidant capacity, superoxide anion radical scavenging capacities, and hydroxyl radical scavenging capacities of EGCG decreased significantly after acetylation modification. The more EGCG acetylation modification sites, the lower the total antioxidant capacity, superoxide anion radical scavenging capacities, and hydroxyl radical scavenging capacities. The antioxidant capacity, superoxide anion radical scavenging capacities, and hydroxyl radical scavenging capacities of 5-acetyl-EGCG (S5-ACE) were higher than 7-acetyl-EGCG (S7-AcE). Combining all the results in this and previous studies, acetylation modification is not conducive to the performance of EGCG antioxidant capacity.

Polysaccharides from red seaweeds: Effect of extraction methods on physicochemical characteristics and antioxidant activities

Seaweed polysaccharides are reported to possess biological and medicinal properties. Specifically, the antioxidant activity of seaweed extracts is the subject of intensive research due to ever-increasing demands from the food and pharmaceutical industries. The structure and composition of polysaccharides (carrageenan, xylan) extracted from four red seaweed species: Chondrus crispus (CC), Ahnfeltiopsis devoniensis (AD), Sarcodiotheca gaudichaudii (SG) and Palmaria palmata (PP) were compared and correlated with their antioxidant activity. Crude polysaccharide extracts were characterized by NMR (1H and 13C), HPLC-SEC, and FTIR spectroscopy. Total phenolic content (TPC), total sugars, sulfate and protein content were determined using spectrophotometric methods. The antioxidant capacity of each fractionated polysaccharide sample was evaluated by the following methods: DPPH (2,2-diphenyl-1-picrylhydrazyl radical), ABTS (2,2-azino-bis-[3-ethylbenzothiazoline-6-sulfonic acid]), superoxide dismutase (SOD), ferric-reducing power in FRAP (Ferric-reducing Antioxidant Power) assays, and the hydroxyl radical (OH) scavenging capacity assay. The highest antioxidant activity was found in extracts from A. devoniensis (ι/κ hybrid carrageenan), while the lowest was in P. palmata (xylans). Moreover, Chondrus crispus extracts did not possess SOD inhibition activity. Polysaccharides evaluated in this study offer high potential for applications in the food, pharmaceutical and biotechnology industries.

Genome Analysis of Bifidobacterium Bifidum E3, Structural Characteristics, and Antioxidant Properties of Exopolysaccharides.

In this study, the antioxidant properties of intact cells (IC), cell-free supernatant (CFS), and cell-free extracts (CFE) and whole genome sequencing of Bifidobacterium bifidum E3 (B. bifidum E3), as well as the structural characteristics and antioxidant properties of EPS-1, EPS-2, and EPS-3, were evaluated. The results revealed that intact cells (IC), cell-free supernatant (CFS), and cell-free extracts (CFE) had potent DPPH (1,1-Diphenyl-2-picrylhydrazyl radical), hydroxyl, and superoxide anion radical scavenging capacities, among which CFS was the best. At the genetic level, we identified a strong carbohydrate metabolism capacity, an EPS synthesis gene cluster, and five sugar nucleotides in B. bifidum E3. Therefore, we extracted cEPS from B. bifidum E3 and purified it to obtain EPS-1, EPS-2, and EPS-3. EPS-1, EPS-2, and EPS-3 were heteropolysaccharides with an average molecular weight of 4.15 × 104 Da, 3.67 × 104 Da, and 5.89 × 104 Da, respectively. The EPS-1 and EPS-2 are mainly comprised of mannose and glucose, and the EPS-3 is mainly comprised of rhamnose, mannose, and glucose. The typical characteristic absorption peaks of polysaccharides were shown in Fourier transform infrared spectroscopy (FT-IR spectroscopy). The microstructural study showed a rough surface structure for EPS-1, EPS-2, and EPS-3. Furthermore, EPS-1, EPS-2, and EPS-3 exhibited potent DPPH, hydroxyl, and superoxide anion radical scavenging capacities. Correlation analysis identified that antioxidant capacities may be influenced by various factors, especially molecular weight, chemical compositions, and monosaccharide compositions. In summary, the EPS that was produced by B. bifidum E3 may provide insights into health-promoting benefits in humans.

Influence of the aqueous matrix on the degradation of cyanotoxins by CWPO: A study on the Iberian Peninsula freshwaters

The increasing occurrence of toxic cyanobacterial blooms worldwide represents a critical health and environmental risk. Catalytic wet peroxide oxidation (CWPO) has emerged as an efficient and environmentally friendly technology for the removal of cyanotoxins in water. Nevertheless, its effectiveness has just been demonstrated in deionized water or simple synthetic aqueous matrices. In this work, the effect of the different components of the aqueous matrix on the CWPO of cyanotoxins was deeply evaluated considering the widespread properties of the Iberian Peninsula freshwaters. The presence of Cl-, HCO3- and SO42- ions reduced the oxidation rate of cylindrospermopsin (CYN) up to 70–80% at the highest concentrations tested (2000, 250 and 500 mg L−1 for Cl-, HCO3- and SO42-, respectively) due to their hydroxyl radical scavenging capacity. The presence of natural organic matter (NOM) resulted in a similar outcome (oxidation rate reduction up to 90% at the highest concentration tested, 20 mg L−1), but in this case due to the consumption of hydroxyl radicals in competition with CYN oxidation. The presence of NO3- and H2PO4- did not show any significant effect on CYN oxidation. Similarly, the presence of cyanobacteria (Chrysosporum ovalisporum, 50 µg chlorophyll-a L−1) did not appreciably affect the CYN oxidation rate. These results were consistent with those obtained by evaluating the impact of real aqueous matrices from drinking water treatment plants (DWTPs) located in Castilla y León and Extremadura regions (Spain) on CWPO performance. This knowledge is key to the implementation of the technology for the treatment of surface waters affected by toxic cyanobacterial blooms.

Bifidobacterium longum LBUX23 Isolated from Feces of a Newborn; Potential Probiotic Properties and Genomic Characterization.

Bifidobacterium longum is considered a microorganism with probiotic potential, which has been extensively studied, but these probiotic effects are strain dependent. This work aims to characterize the probiotic potential, based on the biochemical and genomic functionality, of B. longum LBUX23, isolated from neonates' feces. B. longum LBUX23 contains one circular genome of 2,287,838 bp with a G+C content of 60.05%, no plasmids, no CRISPR-Cas operon, possesses 56 tRNAs, 9 rRNAs, 1 tmRNA and 1776 coding sequences (CDSs). It has chromosomally encoded resistance genes to ampicillin and dicloxacillin, non-hemolytic activity, and moderate inhibition of Escherichia coli ATCC 25922 and to some emergent pathogen's clinical strains. B. longum LBUX23 was able to utilize lactose, sucrose, fructooligosaccharides (FOS), and lactulose. The maximum peak of bacterial growth was observed in sucrose and FOS at 6 h; in lactose and lactulose, it was shown at 8 h. B. longum LBUX23 can survive in gastrointestinal conditions (pH 4 to 7). A decrease in survival (96.5 and 93.8%) was observed at pH 3 and 3.5 during 120 min. argC, argH, and dapA genes could be involved in this tolerance. B. longum LBUX23 can also survive under primary and secondary glyco- or tauro-conjugated bile salts, and a mixture of bile salts due to the high extracellular bile salt hydrolase (BSH) activity (67.3 %), in taurocholic acid followed by taurodeoxycholic acid (48.5%), glycocholic acid (47.1%), oxgall (44.3%), and glycodeoxycholic acid (29.7%) probably due to the presence of the cbh and gnlE genes which form an operon (start: 119573 and end: 123812). Low BSH activity was determined intracellularly (<7%), particularly in glycocholic acid; no intracellular activity was shown. B. longum LBUX23 showed antioxidant effects in DPPH radical, mainly in intact cells (27.4%). In the case of hydroxyl radical scavenging capacity, cell debris showed the highest reduction (72.5%). In the cell-free extract, superoxide anion radical scavenging capacity was higher (90.5%). The genome of B. longum LBUX23 contains PNPOx, AhpC, Bcp, trxA, and trxB genes, which could be involved in this activity. Regarding adherence, it showed adherence up to 5% to Caco-2 cells. B. longum LBUX23 showed in vitro potential probiotic properties, mainly in BSH activity and antioxidant capacity, which indicates that it could be a good candidate for antioxidant or anti-cholesterol tests using in vivo models.

Evaluation of Semecarpus kurzii Engler from Bay Islands for oxidative DNA damage protective activity and in vitro antioxidant potential

Introduction and Aim: Harnessing traditional knowledge of medicinal plants is important for the betterment of mankind. We must safeguard traditional knowledge from misuse by miscreants living in modern societies and knowledge must be available in the public domain for use in drug designing in the healthcare system. Since the beginning of recorded history, Indians have used plants as a source of medicine, and their cultural past is incredibly rich. This study was conducted to evaluate the oxidative stress-induced DNA damage prevention and antioxidant potential of Semecarpus kurzii found in the Bay Islands. Materials and Methods: The scavenging of superoxide, hydroxyl radicals, nitric oxide (NO), 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) radicals, ferric reducing power (FRAP), and lipid peroxidation inhibition activity were tested to determine antioxidant activity. DNA damage inhibition test was used to evaluate the protection against oxidative DNA damage. Results: The S. kurzii extract showed dose-dependent scavenging of DPPH, superoxide anion, nitric oxide, hydroxyl radical and reducing power evaluated by comparing with standard antioxidants (ascorbic acid, alpha-tocopherol and BHT). However, the nitric oxide scavenging (IC50 =186.47) and superoxide scavenging (IC50 = 678.32) was more than that of DPPH (IC50 =28.03) and Hydroxyl radical (IC50 =89.10) scavenging capacity. In addition, S. kurzii extract and ascorbic acid showed lipid peroxidation inhibition activity. The extract also exhibited DNA protection which was confirmed by the DNA damage inhibition assay. Conclusion: Our results corroborated that, the methanolic extract of S. kurzii bark has substantial antioxidant activity and DNA damage inhibition. The potential antioxidant and oxidative DNA damage preventive activity could be due to the existence of polyphenolic compounds in the S. kurzii bark.

Ultrasound-assisted polysaccharide extraction from Cercis chinensis and properites, antioxidant activity of polysaccharide

The purpose of the study was to improve the extraction of polysaccharide from the leaves of Cercis chinensis Bunge using ultrasound, and compare the difference between boiling and ultrasound extraction in terms of polysaccharide content, monosaccharide compounds, and evaluate how the factors affected the bioactivity. The best conditions, according to the single factor experiments and the Box-Bohnken design (BBD), were an intensity of ultrasound of 180 W, duration of extraction of 40 min, proportion of water to material of 15:1 (g/g), and a higher polysaccharide yield of 20.02 ± 0.55 (mg/g) than in boiling extraction (16.09 ± 0.82 mg/g). The antioxidative experiment suggested the polysaccharide by ultrasound exhibited higher DPPH, hydroxyl radical scavenging capacities, and reducing power at 1.2–1.4 mg/mL, which was superior to the boiling polysaccharide. Further analysis showed that the ultrasonic purified polysaccharides like Gla, N-Glu, and GluA contained more total sugar and uronic acids than the boiling method did. This may indicate that the ultrasonic isolation of the polysaccharides increase the antioxidant activity of the polysaccharides.

Insights into the Oxidative Stress Alleviation Potential of Enzymatically Prepared Dendrobium officinale Polysaccharides.

(1) Background: The extraction parameters can dramatically alter the extraction rate and biological activity of polysaccharides. (2) Methods: Here, an enzyme-assisted extraction (EAE) was employed to extract D. officinale polysaccharides (DOPs), and its optimal extraction conditions were established by single-factor and Box-Behnken design (BBD) experiments. Further, on the basis of in vitro antioxidant capacity, the paraquat (PQ)-induced oxidative stress of Caenorhabditis elegans (C. elegans) was chosen as a research model to explore the antioxidant activity of DOPs. (3) Results: The results showed that the extraction yield of DOPs reached 48.66% ± 1.04% under the optimal condition. In vitro experiments had shown that DOPs have considerable ABTS+ radical scavenging capacity (EC50 = 7.27 mg/mL), hydroxyl radical scavenging capacity (EC50 = 1.61 mg/mL), and metal chelating power (EC50 = 8.31 mg/mL). Furthermore, in vivo experiments indicated that DOPs (0.25 mg/mL) significantly prolonged the lifespan, increased antioxidant enzyme activity, and upregulated the expression of daf-16 (>5.6-fold), skn-1 (>5.2-fold), and sir-2.1 (>2.3-fold) of C. elegans. (4) Conclusions: DOPs can be efficiently extracted by EAE and are effective in the reduction of oxidative stress levels in C. elegans.

Antimicrobial and Radical Scavenging Activitıes of Essential Oils from Kaempferia larsenii Sirirugsa

Introduction: K. larsenii (Zingiberaceae) is an endemic and rare species in Thailand. There have been no previous reports on chemical compositions and biological properties of essential oils from the fresh root and rhizome. This research aims to investigate the chemical compositions, antimicrobial and radical scavenging activities of essential oils from the fresh root and rhizome of K. larsenii. Materials and methods: The chemical compositions of hydrodistilled essential oils were analysed by GC-MS technique. The antimicrobial activity was tested by the disc diffusion assay. The Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were also evaluated. The radical scavenging activities were evaluated using ABTS, DPPH and hydroxyl radical scavenging activity assay. Results and discussion: Camphene was considered as the main component in root and rhizome essential oils (36.35 and 48.00 %, respectively). The essential oils showed strong antimicrobial activity against S. aureus. The rhizome essential oil showed strong DPPH and hydroxyl radical scavenging activities while the root essential oil exhibited strong hydroxyl radical scavenging capacity. Conclusions: The essential oils exhibit strong antimicrobial especially Gram-positive bacteria and antioxidant activity. Therefore, it might be used as a potential source of natural antidiarrheal and antioxidant substances for food and cosmeceutical product industries. HIGHLIGHTS The essential oils were obtained from hydrodistillation of the fresh root and rhizome of K. larsenii Camphene was the major component in both root and rhizome essential oils The root and rhizome essential oils showed strong antimicrobial on Gram-positive bacteria and radical scavenging activities This is the first report on the biological activities of the fresh root and rhizome essential oils of larsenii GRAPHICAL ABSTRACT