ABTS Radical Scavenging Activity Research Articles

Antidiabetic, antioxidant, and phytochemical profile of Pennisetum glaucum cultivated in central-southern Morocco and imported from India

Alternative methods of producing food sustainably are being considered due to rapid expanding population, increasing food needs, declining agricultural soils fertility, and ongoing drought. To achieve that, we examined the pharmacological, functional, and nutritional characteristics of two cultivars of pearl millet (Pennisetum glaucum), which are distinguished by their ability to tolerate a variety of climates compared to other cereal grains. In this study, we evaluated the antioxidant and antidiabetic effects of two seeds cultivars: one cultivated in Morocco and the other grown in India. In addition to having a higher energy value (403.91 Kcal), higher protein (9.13 %) and lipid content (7.11 %), and a lower capacity for self-oxidation than the Indian variety due to its fatty acid composition, the content of phenolic compounds of Moroccan millet is well concentrated in its seeds, making it more powerful as an antioxidant and hypoglycemic plant. The ethanolic extract of Moroccan pearl millet showed the greatest total phenolic content (36.278 mg GAE/g extract), DPPH and ABTS radical scavenging activity (IC50 = 152.286 and 252.480 μg/mL respectively), α-amylase and α-glucosidase inhibitory activity (IC50 = 84.439 μg/mL and 224.103 μg/mL respectively). The evidence gathered in this study indicates that P.glaucum possesses characteristics that qualify it as a food, medicinal, and productive plant.

Lipophilized rosmarinic acid: Impact of alkyl type and food matrix on antioxidant activity, and optimized enzymatic production

In this study, the initial focus was on exploring the simultaneous impact of the oil-based food matrix and the polarity of rosmarinic acid derivatives on the antioxidant properties. Rosmarinic acid (RA) showed remarkable DPPH, FRAP, and ABTS radical scavenging activities, followed by methyl rosmarinate (MR) and ethyl rosmarinate (ER). In bulk oil, both conjugated dienes and p-AnV values reached a peak in the following order after 30 days: ER > MR > RA = BHT > control (no antioxidant). In the oil structured using monoacylglycerol, MR was more effective than ER and RA. For ethyl cellulose oleogel, emulsion, and gelled emulsion systems, RA was more effective. Additionally, after confirming the importance of the food matrix on the antioxidant activity of RA derivatives, the lipophilization of RA with ethanol was optimized as a model with Lipozyme 435 in hexane. A conversion yield of as high as 85.59% for ER was achieved, as quantified by HPLC-UV and confirmed by HPLC-DAD-ESI-qTOFMS.

Effects of Extraction Methods on the Physicochemical Properties and Biological Activities of heteroglycans from Hibiscus sabdariffa calyx

The hot-water extraction method has been employed to enhance the diffusion rate of heteroglycans, thereby augmenting the extraction efficiency. This study investigates the antioxidant activities and immunological properties of water-soluble polysaccharides derived from the Hibiscus sabdariffa calyx (HWPF and LWPF). These polysaccharides were isolated through two distinct extraction methods involving hot water followed by ethanol precipitation. The physicochemical characterization was conducted through a series of experiments encompassing monosaccharide composition, ultraviolet-visible spectrum analysis, and Fourier-transform infrared (FT-IR) spectroscopy. The evaluation of antioxidative properties employed various techniques, including DPPH and ABTS radical scavenging activities, Ferric Reducing Antioxidant Power, ferrous chelating power, total reducing power, and protection against DNA damage. The assessment of anti-inflammatory potential involved the inhibition of hemolytic activity induced by a hypotonic solution and heat. Furthermore, the impact of the polysaccharides on the production of pro-inflammatory cytokines was analyzed through Luminex assay and RTPCR assay in PBMCs and LPS-stimulated RAW 264.7 cells, respectively. The findings revealed that heteroglycans (LWPF and HWPF) exhibit a content of Ara-Man-Rha-GluA-GalA (41.2:17.2:15.7:9.2:8.8) and Ara-Glu-Rha-Xyl-GluA-Man (31.5:23.8:12.16:10.4:7:6) with molecular weights of approximately 4.5 KDa and 41.3 KDa, respectively. HWPF demonstrated robust metal chelating and scavenging activities. Additionally, each fraction exhibited substantial protection of DNA against damage induced by H2O2. LWPF was observed to significantly down-regulate the expression of pro-inflammatory cytokines IL-6 and COX-2 at both transcriptional and translational levels, along with inhibiting NO production. In summary, these results indicate that the choice of extraction methods influences both the structure and biological activities of heteroglycans, providing valuable insights into the structure-activity relationship.
 Keywords: Hibiscus sabdariffa, heteroglycans, hot water extraction, physicochemical properties, Antioxidant activity, Pro-inflammatory cytokines.

Physicochemical and antioxidant properties of pectin fractions extracted from lemon (Citrus Eureka) peels

Pectin, a natural polysaccharide, holds versatile applications in food and pharmaceuticals. However, there is a need for further exploration into extracting novel functional fractions and characterizing them thoroughly. In this study, a sequential extraction approach was used to obtain three distinct lemon pectin (LP) fractions from lemon peels (Citrus Eureka): LP extracted with sodium acetate (LP-SA), LP extracted with ethylenediaminetetraacetic acid (LP-EDTA), and LP extracted with sodium carbonate and sodium borohydride (LP-SS). Comprehensive analysis revealed low methyl-esterification in all fractions. LP-SA and LP-SS displayed characteristics of rhamnogalacturonan-I type pectin, while LP-EDTA mainly consisted of homogalacturonan pectin. Notably, LP-SA formed self-aggregated particles with rough surfaces, LP-EDTA showed interlocking linear structures with smooth planes, and LP-SS exhibited branch chain structures with smooth surfaces. Bioactivity analysis indicated that LP-SA had significant apparent viscosity and ABTS radical scavenging activity, while both LP-EDTA and LP-SS showed excellent thermal stability according to thermogravimetric analysis (TGA). Furthermore, LP-SS exhibited remarkable gel-forming ability and significant hydroxyl free radicals scavenging activity. In conclusion, this study presents a novel method for extracting various lemon pectin fractions with unique structural and bioactive properties, contributing insights for advanced applications in the food and pharmaceutical sectors.

Assessment of in vitro antimicrobial and antioxidant activities of Broussonetia × hanjiana M. Kim 

The fruit and bark of Broussonetia × hanjiana M. Kim (Kkujidaknamu, Korean paper mulberry) have been used as a resource for medicine and paper in Korea and Korean traditional paper (Hanji), made from extract of the B. × hanjiana bark, has been used to package dry foods. The present study was carried out to evaluate the in vitro antimicrobial and antioxidant activities of B.× hanjiana extract. The antimicrobial activity of four fractions of ethanol extract of the plant collected in July was evaluated through disc diffusion and minimal inhibition concentration (MIC) method against three Gram-positive strains, two Gram-negative strains, and one yeast. The ether and ethyl acetate fraction of ethanol extract from B. × hanjiana bark exhibited the highest antimicrobial activity with the lowest MIC value against the tested Gram-positive bacteria. The MIC of the hexane and ether fraction against Gram-negative bacteria was not detected in any sample extracts and the MIC was not observed against Saccharomyces cerevisiae in any fractions. The antioxidant activity of ethanol and hot water extract of the plant was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay. The ethanol extract showed relatively higher DPPH and ABTS radical scavenging activity than the hot water extract, regardless of the samples. The results of total phenolic and flavonoid contents were not consistent with the results of antioxidant activity and it shows antioxidant activity is not only affected by the polyphenol content but also can occur by some other phytochemicals. The antimicrobial and antioxidant activity was influenced by plant organ or extract solvent. These findings may confirm the potential of this plant as an antimicrobial and antioxidant agent.

Active packaging coating based on agarose grafted with benzoic acid derivatives: Preparation, characterization and application in fish preservation

Agarose based on gel strength can not meet the needs of diverse applications, and the structural modification of agarose is helpful to improve its functional properties and promote the economic benefits of the agarose industry chain. This study focuses on making agarose as an active packaging material with specific functions. Agarose was modified with p-hydroxybenzoic acid (Ph) and 3, 4-dihydroxybenzoic acid (Da) to produce agarose derivatives with grafting rates of 4% and 12% (Ph-Ag@4%, Ph-Ag@12%, Da-Ag@4%, and Da-Ag@12%). Characterization techniques confirmed the successful introduction of Ph and Da onto agarose, with grafting occurring at the C-6 position in d-galactose. Both Ph-Ag and Da-Ag exhibited significantly enhanced antioxidant and antibacterial properties. Da-Ag@12% showed remarkable improvements in DPPH and ABTS radical scavenging activities from 0% to 66.01% and 2.49%–84.73%, respectively. Ph-Ag@12% exhibited inhibition rates of 100% against Escherichia coli and Staphylococcus aureus. After modification, Ph-Ag and Da-Ag maintained good gelling and film-forming properties. Fish preservation experiments revealed both Ph-Ag and Da-Ag coatings effectively suppressed microbial growth, slowed down lipid oxidation, minimized water loss, and maintained the texture and appearance of fish meat. These coatings improved fish meat quality and extended its shelf life, with Da-Ag@12% showing the most promising results.

Tissue-specific variations of piperine in ten populations of Piper longum L.: bioactivities and toxicological profile

P. longum L., one of the most significant species of the genus Piperaceae, is most frequently employed in Indian-Ayurvedic and other traditional medicinal-systems for treating a variety of illnesses. The alkaloid piperine, is the key phytoconstituent of the plant, primarily responsible for its’ pharmacological-impacts. The aim of the study is to analyse the intra-specific variation in piperine content among different chemotypes (PL1 to PL 30) and identify high piperine yielding chemotype (elite-chemotype) collected from 10 different geographical regions of West Bengal by validated HPTLC chromatography method. The study also focused on the pharmacological-screening to better understand the antioxidant activity of the methanol extracts of P. longum by DPPH and ABTS radical-scavenging activity and genotoxic activity by Allium cepa root tip assay. It was found that the P. longum fruit chemotypes contain high amount piperine (highest 16.362 mg/g in chemotype PL9) than the stem and leaf chemotypes. Both DPPH and ABTS antioxidant assays revealed that P. longum showed moderate radical-scavenging activity and the highest activity was found in PL9 (fruit) chemotype with IC50 values of 124.2 ±0.97\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pm 0.97$$\\end{document} and 104 ±0.78\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pm 0.78$$\\end{document} µg/ml respectively. The A. cepa root tip assay showed no such significant genotoxic-effect and change in mitotic-index. The quick, reproducible, and validated HPTLC approach offers a useful tool for determining quantitative variations of piperine among P. longum chemotypes from different geographical-regions and also according to the different tissues and choose elite genotypes with high piperine production for continued propagation and commercialization for the pharmaceutical sector. Additionally, the plant's in-vitro antioxidant property and lack of genotoxicity directly supports its’ widespread and long history of use as a medicinal and culinary plant.

Valorization of cashew nut testa phenolics through nano-complexes stabilized with whey protein isolate and β-cyclodextrin: Characterization, anti-oxidant activity, stability and in vitro release

Cashew nut testa (CNT) is an underutilized cashew by-product rich in polyphenols. The applications of CNT are limited due to its astringency, less solubility, and instability of polyphenols during the processing. Nanoencapsulation was used to overcome these limitations. β-cyclodextrin alone and in combination with whey protein isolate (WPI) was used for nano-complex preparation. The WPI/CD-CNT nano-complex powder showed higher encapsulation efficiency (86.9%) and yield (70.5–80%) compared to CD-CNT powder. Both the spray-dried powders showed improved thermal stability, higher solubility (97%), less moisture content, and increased DPPH and ABTS radical scavenging activities indicating potential food and agricultural applications. In addition, the nano-complex powders showed a controlled release of core bio-actives under gastric and intestinal pH compared to the non-encapsulated CNT phenolic extract. Degradation kinetics studies of the CNT extract after thermal and light treatments were also discussed. Both the nano-complexes showed high stability under light and thermal treatment. The results suggest that valorization of CNT can be done through nano-complex preparation and WPI and β-CD are efficient carrier materials for the encapsulation of polyphenols with potential applications in food and agriculture.

The Role of Ultrasound Cavitation Combined with Alcalase Enzyme in Improving the Structural and Antioxidant Attributes of Sulfated Polysaccharide from Yellowfin (Thunnus albacares) Skin

ABSTRACT Alcalase enzyme (1 mg) and ultrasound (400 W) at 0–20 min were applied to obtain sulfated polysaccharides from yellowfin skin. Applying 15 min ultrasound resulted in a 0.12% increase in the rate of recovery yield. The intact structure of polysaccharides was determined by Fourier transform infrared spectroscopy, X-ray diffractometry, and scanning electron microscope. Ultrasound improved the thermal behavior of sulfated polysaccharides by affecting their microstructure, as analyzed by DSC. The color characterization (L*, a*, and b*) of ultrasound-treated samples was found to be superior compared to the control. Applying 15 min led to 16% and 9% enhancing DPPH and ABTS radical scavenging activities along with improving ferric-reducing antioxidant power of the polysaccharide.

Crude extracts of <i>Momordica cochinchinensis</i> (Lour.) Spreng exerts antioxidant and anti-neuroinflammatory properties in LPS-stimulated BV2 microglia

Purpose: To evaluate the antioxidant and anti-neuroinflammatory properties of the leaves, seeds and pulp of Momordica cochinchinensis  Spreng (commonly known as Gac) in vitro and in lipopolysaccharide (LPS)-activated BV2 microglial cells.
 Methods: Lipopolysaccharide was applied to BV2 cells for 24 h in the presence or absence of Gac extracts. Then, levels of reactive oxygen  species (ROS) were assayed using CM-H2DCFDA method, while nitric oxide (NO) level was determined with Griess reagent. The levels of  TNF-α and IL-6 were  determined using ELISA. Three different assays were used for determination of in vitro antioxidant activities of the  extracts, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging; 2,2’-azinobis-3- ethylbenzthiazoline-6-sulfonic acid (ABTS) scavenging,  and ferric-reducing antioxidant power (FRAP). Total flavonoids content (TFC) and total phenolic content (TPC) were also determined. 
 Results: There were significantly higher levels of ROS, NO, TNF and IL-6 in LPS-treated BV2 cells than in control cells (p < 0.05). However,  exposure of LPS treated BV2 cells to the leaf, seed and pulp extracts of Gac led to marked decreases in levels of ROS and inflammatory  mediators, when compared with untreated cells, with the seed extract producing significantly larger decreases in levels of ROS and inflammatory mediators than the leaf and pulp extracts (p < 0.05). The DPPH and ABTS radical scavenging activities and total reducing  power activities of the seed extract were superior to those of the leaf and pulp extracts. Moreover, the seed extract showed higher  contents of TFC and TPC than the other two extracts.
 Conclusion: Gac extracts exert antioxidant and anti-neuroinflammatory effects on LPS-activated BV2 cells and in an in vitro model.  Therefore, Gac extracts, especially seed extract, may be beneficial in the preparation of innovative antioxidative and anti-neuroinflammatory herbal remedies, as well as dietary supplements. 

Comparative Analysis of Polyphenol Content and Antioxidant Activity of Different Parts of Five Onion Cultivars Harvested in Korea.

Onions are typically consumed as the bulb, but the peel and root are discarded as by-products during processing. This study investigated the potential functional use of these by-products by analyzing the polyphenols, antioxidant compounds, and antioxidant activity contained in onions. In this study, the bulb, peel, and root of five onion cultivars ('Tank', 'Bomul', 'Gujji' 'Cobra', and 'Hongbanjang') harvested in Korea were investigated. Caffeic acid and quercetin were most abundant in the peel, whereas methyl gallate was the predominant polyphenol in the bulb. Both DPPH and ABTS radical scavenging activity were higher in onion peel and root than in the bulb. These findings suggest that onion peel and roots, which are often discarded, have abundant antioxidant substances and excellent antioxidant activity. This study provides basic data for the future use of onion peel and roots as functional ingredients with high added value.

저온 저장 후지 사과의 과피와 과육 중 파이토케미컬 함량의 상관관계

This study determined the relationships between the total anthocyanin content in apple skin and the total polyphenols, flavonoids, proanthocyanidins, and soluble solids contents in the flesh of cold-stored Fuji apples. Total anthocyanin content in apple skin ranged from 0.130±0.005 mg CE/g fw to 0.262±0.028 mg CE/g fw, and the overall average was 0.200±0.008 mg CE/g fw. The total polyphenolic compounds in the flesh was ranged from a 4.283±0.141 mM GAE/g fw to 8.207±0.234 mM GAE/g fw, and the average content was 6.275±0.177 mM GAE/g fw. The total flavonoid content ranged from 4.510±0.080 mM QE/g fw to 2.467±0.458 mM QE/g fw, and the average total flavonoid content was about 3.586 mM QE/g fw. The total proanthocyanidin content was relatively high, ranging from 3.475±0.577 mM EE/g fw to 6.816±0.277 mM EE/g fw, and the soluble solid in the flesh was about 12 °Brix to 14 °Brix. The DPPH radical scavenging activity of extracts from apple flesh ranged from 66.36% to 94.99%, and the ascorbate equivalent concentration was 0.482 mM. The ABTS radical scavenging activity was 99.12% to 99.9%, indicating a higher inhibitory activity than the DPPH inhibitory activity, and the ascorbate equivalent concentration was 0.486 mM. The correlation between the total anthocyanin and total polyphenolic compounds was y = 15.192x + 3.2169 (R2=0.2748), but the concentration of total polyphenolic compounds increased when the total anthocyanin content was increased. The correlation equation of total anthocyanin with total flavonoids was y = 15.18x + 0.5555 (R2=0.6226), with total proanthocyanin was y = 14.918x + 2.3422 (R2=0.3372), and with soluble solid was y = 10.558x + 11.126 (R2=0.1925), indicating that the correlation of total anthocyanin with total flavonoid was higher than that with soluble solid.

Evaluation of the Shelf life of Ready-to-Eat Fresh Bamboo Sprouts (Phyllostachys edulis) Packaged in a Modified Atmosphere or Vacuum: A Comparative Study.

During the last decades, the consumption of bamboo sprouts (Phyllostacys edulis) has increased because they are considered a "superfood". However, this product is characterized by a short shelf life due to the deterioration in quality parameters. The aim of this study was to investigate the application of two modified atmosphere packaging (MAP) systems (MAP1: 2% O2, 5% CO2, 93% N2 and MAP2: 3% O2, 7% CO2, 90% N2) to fresh-shelled ready-to-eat bamboo sprouts and compare these packaging systems with vacuum packaging during storage for 28 days at 4 °C using heat-sealable polyamide and polyethylene (PA/PE) trays. Several chemical-physical parameters (moisture content, water activity, pH, headspace composition, and firmness) were monitored, as well as CIELab colorimetric parameters and microbial growth. The quantification of selected organic acids was performed via UHPLC. Mathematical kinetic models were applied to study the evolution of total phenol (TPC), flavonoid (TFC), and carotenoid content (TCC) during storage. The evolution of antioxidant potential investigated by ABTS, DPPH, and β-carotene bleaching tests was also assessed. Results showed that at the end of the storage period, significant variations in the colorimetric parameters are detectable between the sprouts apical portion and the basal one, regardless of both applied MAPs. A linear reduction in both DPPH and ABTS radical scavenging activity was evidenced during storage, regardless of the type of packaging applied. In DPPH test samples packaged in MAP after 28 days of storage, they retain good antioxidant activity, whereas in vacuum, this activity is reduced by 50% compared to the initial value (IC50 values from 24.77 to 32.74 μg/mL and from 24.77 to 71.12 μg/mL for MAP2 and vacuum, respectively).

Unifying Theory and Experiments: Multi-Target Pharmacology of Dajihan Pill Against Hyperlipidemia

Background: The increasing incidence of hyperlipidemia (HLP) is attributed to the imbalance in redox homeostasis, aberrant lipid metabolism, and the excessive intake of empty calories. Dajihan Pill (DJHP) is a Traditional Chinese Medicine (TCM) formula composed of Zingiberis Rhizoma (ZR), Piperis Longi Fructus (PLF), Alpiniae Officinarum Rhizome (AOR), and Cinnamomi Cortex (CC) in a ratio of 3:2:3:2. It exhibits a significant preventive effect on HLP. Certainly, the active components and the precise mechanism of action are not fully understood. Therefore, this study aims to elucidate the preventive and ameliorative mechanisms of DJHP against HLP by integrating network pharmacology, molecular docking, and experimental validation. Method: Based on the pharmacological method, active ingredients in DJHP and targets were extracted from Traditional Chinese Medicine System Pharmacology (TCMSP) and UniProt. Then core compounds and targets were obtained by constructing “compounds-targets-disease” and proteinprotein interaction (PPI) network. Gene Ontology (GO) function analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) were employed to elucidate further the associated action mechanism. The molecular binding mechanisms between the core ingredients and targets were elucidated through molecular docking. Additionally, the antioxidant capacities of DJHP extracts were investigated by assessing their DPPH, hydroxyl, and ABTS radical scavenging activities. Results: A total of 45 active compounds and 258 targets were identified in DJHP. Network analysis indicated that quercetin, beta-sitosterol, kaempferol, and oleic acid might serve as core bioactive compounds. Seven core targets, including AKT1, INS, and TNF, were identified as potential preventive targets. GO analysis suggested the improvement of HLP by DJHP may be related to the lipid metabolic process, high-density lipoprotein particle, triglyceride binding, and inflammatory response. The KEGG analysis indicated TNF, HIF-1, and AMPK signaling pathways were involved. The observations of active compounds binding with core targets indicated an excellent combination. Additionally, antioxidant results showed that DJHP exhibited significant DPPH, hydroxyl, and ABTS radical scavenging activities. Conclusion: Theoretical and experimental investigations indicate that DJHP can effectively modulate various signaling pathways and enhance the redox system, thus mitigating HLP. Our work provided a basis for the pharmacological study of DJHP in preventing HLP and further research.

망고스틴 꼭지를 활용한 항산화 및 항염증에 대한 기초자료 연구

By verifying the antioxidant and anti-inflammatory properties of Garcinia mangostana stem 70% ethanol extract (GMSE), we confirmed its utility as a natural material. In this study, experiments using GMSE were conducted to discover natural substances related to antioxidant and anti-inflammatory activities. First, as a result of measuring the total polyphenol content of GMSE, the content was confirmed to be 508.82 ± 0.98 mg TAE/100 g. To confirm the antioxidant activity of GMSE, electron donating activity and ABTS radical scavenging activity were measured. The electron donation showed an 87.2% result at a final concentration of 1,000 μg/mL, and the ABTS radical measurement showed an activity close to 100% at a concentration of 50 μg/mL, and confirmed an effect similar to that of vitamin C, the control group. In order to measure anti-inflammatory activity through cell experiments, the cell viability of GMSE for RAW 264.7 cell, a macrophage, was confirmed. Based on these results, NO inhibitory activity, a factor related to inflammation, was measured below 500 μg/mL concentration. As a result, an inhibitory effect of 26.83% was confirmed at the final concentration of 500 μg/mL. Based on this, it has been verified that GMSE is effective in antioxidant and anti-inflammatory activities, and it is intended to be used as basic data for the use of natural materials afterwards.

Investigation of in vitro antidiabetic and antioxidant activity of hawthorn vinegar obtained from Endemic Crataegus tanacetifolia (Poir.) Pers.

In this study, the in vitro antidiabetic, antioxidant activity and total flavonoid content (TFC) and total phenolic content (TPC) of vinegar obtained from endemic Crataegus tanacetifolia (Lam.) Pers. (Rosaceae), (hawthorn) were examined. The hawthorn vinegar obtained from Malatya province (MS) and the vinegar (TS) obtained from Konya were used as study material. Their antidiabetic activity was determined by α-amylase and α-glucosidase inhibitory methods. Antioxidant activities were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and ferrous iron chelating (FCA) assays. The absorbance were read in the Elisa reader and evaluated with Excel and GraphPad programs. The MS has been found to have higher α- amylase (95.12± 3.71%) and α-glucosidase inhibitory (81.62 ± 0.33%) effects. The TS demonstrated (94.13 ± 3.85%) α-amylase and (75.35 ± 2.19%) α-glucosidase inhibitory activity, respectively. The TPC was found to be in TS (467.59 ± 6.73) mg GAE/mL MS (328.46 ± 5.50) mg GAE/mL. The TFC was found as (1.94 ± 10.36) mg CE/mL and (1.32 ± 10.96) mg CE/mL in TS and MS vinegar, respectively. The FCA was found to be in TS (33.37 ± 0.53%) MS (31.08 ± 10.87%). The DPPH radical scavenging activity was found as (73.82 ± 2.12%) in TS and (80.12 ± 4.45%) in MS. ABTS radical scavenging activity was found to be the highest in TS with (82.51± 0.78%) and in MS found as (78.65 ± 0.55%). The antidiabetic, antioxidant activity, TPC and TFC determinations of these vinegars were performed for the first time with these methods.

Enhancement of nutrient bioaccessibility and functional property of chicken bone powder through steam explosion

There are technological and nutritional challenges to efficient use of chicken bone in foods, due to its low bioaccessibility and techno-functionality. The impacts of steam explosion (SE), autoclave, steam treatment on the powder characteristics and the effect of SE on the physicochemical properties and bioaccessibility of chicken bone powders were investigated. X-ray diffraction and Fourier transform infrared spectroscopy indicated that SE treatment might increase crystallinity, partial loss of organic substance, but not completely destroyed its crystal type. SE had a smaller particle size of chicken bone powder with time and energy saving compared with other treatments, and it was conducive to improving the color acceptability. Compared with native chicken bone powder, SE significantly decreased the average particle size of powder by 79.23 %, whereas its specific surface of unit volume increased by 119.98 %. And SE improved the techno-functionality which evaluated by water holding capacity (4.19 %), oil holding capacity (10.53 %), water solubility index (117.64 %) and ABTS radical scavenging activity (14.05 %). The higher protein digestibility, calcium and major amino acids contents in chicken bone powder during digestion showed SE upgraded the bioaccessibility. The results were suggestive that steam explosion was an efficient process for preparing bone powder with improved techno-functionality and noticeable bioaccessibility.

Bamboo leaf extract treatment alleviates the surface browning of fresh-cut apple by regulating membrane lipid metabolism and antioxidant properties.

The effect of bamboo leaf extract (BLE) on controlling the browning of fresh-cut apple stored at 4 °C was investigated. Browning index, H2 O2 content, O2 - production rate, malondialdehyde (MDA) contents, total phenolic content (TPC) and soluble quinone content (SQC), the activities of polyphenol oxidase (PPO), peroxidase (POD), lipoxygenase (LOX), superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), DPPH (2,2-diphenyl-2-picryl-hydrazyl) and ABTS [2,2-azinobis(3-ethylbenzothiazoline- 6-sulfonic acid)] radical scavenging activities, and the expression of genes related to browning were all investigated. BLE effectively alleviated the surface browning of fresh-cut apple, accompanied by a reduction in SQC, LOX activity, H2 O2 , O2 - production rate and MDA accumulation. Furthermore, BLE treatment enhanced the TPC, enzymatic (SOD, CAT, APX and POD) and non-enzymatic antioxidant activities. Principal component analysis and Pearson correlation analysis found the browning inhibition by BLE is not through the reduction of phenolic substrates and PPO activity. BLE controls the browning of fresh-cut apple by increasing the antioxidant capacity to scavenge ROS, which could alleviate oxidative damage and maintain the membrane integrity. © 2023 Society of Chemical Industry.

Optimization of Three Extraction Methods and Their Effect on the Structure and Antioxidant Activity of Polysaccharides in Dendrobium huoshanense.

Dendrobium huoshanense is a famous edible and medicinal herb, and polysaccharides are the main bioactive component in it. In this study, response surface methodology (RSM) combined with a Box-Behnken design (BBD) was used to optimize the enzyme-assisted extraction (EAE), ultrasound-microwave-assisted extraction (UMAE), and hot water extraction (HWE) conditions and obtain the polysaccharides named DHP-E, DHP-UM, and DHP-H. The effects of different extraction methods on the physicochemical properties, structure characteristics, and bioactivity of polysaccharides were compared. The differential thermogravimetric curves indicated that DHP-E showed a broader temperature range during thermal degradation compared with DHP-UM and DHP-H. The SEM results showed that DHP-E displayed an irregular granular structure, but DHP-UM and DHP-H were sponge-like. The results of absolute molecular weight indicated that polysaccharides with higher molecular weight detected in DHP-H and DHP-UM did not appear in DHP-E due to enzymatic degradation. The monosaccharide composition showed that DHPs were all composed of Man, Glc, and Gal but with different proportions. Finally, the glycosidic bond types, which have a significant effect on bioactivity, were decoded with methylation analysis. The results showed that DHPs contained four glycosidic bond types, including Glcp-(1→, →4)-Manp-(1→, →4)-Glcp-(1→, and →4,6)-Manp-(1→ with different ratios. Furthermore, DHP-E exhibited better DPPH and ABTS radical scavenging activities. These findings could provide scientific foundations for selecting appropriate extraction methods to obtain desired bioactivities for applications in the pharmaceutical and functional food industries.

Comparison of in vitro antioxidant capacities of Phragmites communis Trin. and Phragmites japonica Steud.

The rhizome of Phragmites communis Trin. is used for vomiting and belching by clearing stomach and the sprout is used as tea. Phragmites japonica is similar with P. communis except the color of sheath is purple. This study is aimed to compare the in vitro antioxidant activity, total polyphenol and flavonoids contents of P. communis and P. japonica. The antioxidant activities of fractions from the two Phragmites plants were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay. The antioxidant activity varied with plant parts and extract solvents. The fractions of leaf extract from the two Phragmites plants (4.06± 1.32-16.47±1.28%) showed higher antioxidant activity by DPPH assay compared with rhizome fractions of two Phragmites plants (0.00±0.00-14.15±0.07%), these are lower compared with ascorbic acid and butylhydroxyanisole (BHA). The highest ABTS radical scavenging activity was found for rhizome ether fraction, namely 74.95±0.56% and 73.04±1.85% for P. communis and P. japonica, these are higher than BHA. The total polyphenol and flavonoids contents were different with plant parts and extract solvents, likewise antioxidant activity. A significant correlation was shown between DPPH and ABTS radical scavenging activity. Considering the results of this study, the leaves and stems of P. communis and P. japonica are expected to be used as natural antioxidants.