DPPH Radical Scavenging Ability Research Articles

Effect of Stevia rebaudiana stem waste extract on lipid oxidation of salted-dried Pacific saury during chilled storage

Lipid oxidation is the major form of deterioration in salted-dried fish during storage. We here studied the use of Stevia rebaudiana stem (SRS) waste for impeding lipid oxidation of salted-dried Pacific saury fillets during chilled storage. Compared with Vitamin C (VC), the SRS extract (0.2%) significantly delayed lipid oxidation of the salted-dried fish, as determined through assays of the peroxide value, conjugated diene, thiobarbituric acid reactive substances, and acid value; VC is commonly used in salted-dried products. The color results further confirmed the feasibility of the SRS extract in maintaining the quality of the salted-dried Pacific saury fillets. The antioxidant mechanism studies unveiled that the SRS extract exhibited a higher Fe2+-chelating ability than VC, whereas the extract exhibited lower DPPH and ABTS radical-scavenging abilities than VC. This indicated that the high efficacy of the SRS extract in retarding lipid oxidation may be attributable to its higher Fe2+-chelating ability. The in situ Fe2+-chelating assay conducted using confocal laser scanning microscopy further confirmed this conclusion. Potential functional phenolic compounds in the SRS extract were then profiled using the LC-MS method. The SRS waste extract can thus be applied as a natural antioxidant for delaying lipid oxidation of salted-dried fish.

Physiological and oxidative stress response of carrot (Daucus carota L.) to jumping plant-louse Bactericera trigonica Hodkinson (Hemiptera: Psylloidea) infestation

BackgroundCarrot is an important vegetable crop grown worldwide. The major economic problem in carrot cultivation is yellow disease caused by Bactericera trigonica, which induces biotic stress and has the greatest impact on crop productivity. Comprehensive studies on the mechanism of carrot defense response to biotic stress caused by B. trigonica infestation have yet to be conducted.MethodsThe changes in photosynthetic pigments, proline, TPC, H2O2 and MDA content, DPPH radical scavenging ability, and antioxidant enzyme activity of SOD, CAT, and POX in carrot leaves in response to insect sex (female and male), rapid response (during the first six hours), and long-term response to B. trigonica infestation were evaluated.ResultsThe results of our study strongly suggest that B. trigonica infestation causes significant changes in primary and secondary metabolism and oxidative status of carrot leaves. Photosynthetic pigment content, TPC, and DPPH and CAT activities were significantly reduced in carrot leaves in response to insect infestation. On the other hand, proline, H2O2 content, and the activity of the antioxidant enzymes superoxide dismutase and peroxidase were increased in carrot leaves after B. trigonica infestation. The results indicate that B. trigonica attenuates and delays the oxidative stress responses of carrot, allowing long-term feeding without visible changes in the plant. Carrot responded to long-term B. trigonica infestation with an increase in SOD and POX activity, suggesting that these enzymes may play a key role in plant defense mechanisms.ConclusionsThis is the first comprehensive study strongly suggesting that B. trigonica infestation causes significant changes in primary and secondary metabolism and an attenuated ROS defense response in carrot leaves that enables long-term insect feeding. The information provides new insights into the mechanisms of carrot protection against B. trigonica infestation.

Biological Activity Evaluation of Olive, Grape, and Fig at Various Mixing Ratios

Purpose: This study aimed to evaluate the antioxidation and enzymatic activity-related qualities of four mixtures prepared with different mixing ratios of olives (O), grapes (V), and figs (F), which are representative ingredients of the Mediterranean diet. Methods: Following mixtures were prepared: olives–figs (OF), grapes–figs (VF), and olives–grapes–figs (OVF). For mixture preparation, the ingredients were mixed in following ratios: olives-to-grapes, olives-to-figs, and grapes-to-figs at ratios of 1:1 (30 g of each) as well as olives-to-grapes-to-figs at a ratio of 1:1:1 (20 g of each). The antioxidant (total polyphenol and flavonoid contents along with 2,2-diphenyl-1-picrylhydrazyl [DPPH] and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) [ABTS] radical scavenging) and enzymatic (α-glucosidase inhibitory and angiotensin-converting enzyme [ACE] inhibitory) activities of the four aforementioned mixtures were measured. Results: OV and OVF mixtures showed the highest total polyphenol (27.25±0.22 mg TAE/g) and flavonoid contents (27.9 ± 2.14 mg QE/g), respectively. DPPH radical scavenging ability was highest in OV (92.86 ± 0.17%). The highest ABTS radical scavenging activity was registered in the OVF mixture (42.88±1.19%). α-glucosidase and ACE inhibitory activity measurements were highest in the OVF mixture (79.75±0.15% and 88.61±0.08%, respectively). Conclusion: Highest physiological activity levels (i.e., anti-oxidation and enzymatic activity) were observed in the olive, grape, and fig (1:1:1) mixture, hence, its regular consumption could improve metabolic syndrome.

Acidic electrolyzed-oxidizing water treatment mitigated the disease progression in Phomopsis longanae Chi-infected longans by modulating ROS and membrane lipid metabolism

Postharvest harmful pathogenic infestation leads to rapid decay in longan fruit. Compared with P. longanae-infected longans, AEOW alleviated fruit disease severity and diminished the O2-. production rate and MDA content. It also increased APX, CAT, and SOD activities, delayed the decrease in the levels of GSH and AsA, as well as the reducing power and DPPH radical scavenging ability, which resulted in a decline in membrane lipid peroxidation in P. longanae-infected longans. Additionally, AEOW reduced LOX, lipase, PI-PLC, PC-PLC, and PLD activities, maintained higher levels of PC, PI, IUFA, USFAs, and U/S, while reducing levels of PA, DAG, SFAs, and CMP. These effects alleviated membrane lipid degradation and peroxidation in P. longanae-infected longans. Consequently, AEOW effectively maintained membrane integrity via improving antioxidant capacity and suppressing membrane lipid peroxidation. This comprehensive coordination of ROS and membrane lipid metabolisms improved fruit resistance and delayed disease development in longans.

Autumn Olive (Elaeagnus umbellata Thunb.) Berries Improve Lipid Metabolism and Delay Aging in Middle-Aged Caenorhabditis elegans.

This study evaluated the positive effects of autumn olive berries (AOBs) extract on delaying aging by improving lipid metabolism in middle-aged Caenorhabditis elegans that had become obese due to a high-glucose (GLU) diet. The total phenolic content and DPPH radical scavenging abilities of freeze-dried AOBs (FAOBs) or spray-dried AOBs (SAOBs) were examined, and FAOBs exhibited better antioxidant activity. HPLC analysis confirmed that catechin is the main phenolic compound of AOBs; its content was 5.95 times higher in FAOBs than in SAOBs. Therefore, FAOBs were used in subsequent in vivo experiments. FAOBs inhibited lipid accumulation in both the young adult and middle-aged groups in a concentration-dependent manner under both normal and 2% GLU conditions. Additionally, FAOBs inhibited ROS accumulation in a concentration-dependent manner under normal and 2% GLU conditions in the middle-aged worms. In particular, FAOB also increased body bending and egg production in middle-aged worms. To confirm the intervention of genetic factors related to lipid metabolism from the effects of FAOB, body lipid accumulation was confirmed using worms deficient in the daf-16, atgl-1, aak-1, and akt-1 genes. Regarding the effect of FAOB on reducing lipid accumulation, the impact was nullified in daf-16-deficient worms under the 2% GLU condition, and nullified in both the daf-16- and atgl-1-deficient worms under fasting conditions. In conclusion, FAOB mediated daf-16 and atgl-1 to regulate lipogenesis and lipolysis in middle-aged worms. Our findings suggest that FAOB improves lipid metabolism in metabolically impaired middle-aged worms, contributing to its age-delaying effect.

A degradable multi-functional packaging based on chitosan/silk fibroin via incorporating cellulose nanocrystals-stabilized cinnamon essential oil pickering emulsion

In this study, cellulose nanocrystals (CNC) exhibited a higher aspect ratio derived from Rosa roxburghii pomace (RRP), enabling them to effectively carry more charge and consequently form a Pickering emulsion (PE) of cinnamon essential oil (CEO) with enhanced stability. This mixture was then incorporated into a chitosan/silk fibroin (CS/SF) matrix to create an activated food packaging film successfully. Additionally, the cinnamon essential oil - Pickering emulsion (CEO-PE) prepared in this study exhibited superior compatibility with the film substrate. Scanning electron microscopy (SEM) results showed that the Pickering emulsion was uniformly distributed in the CS/SF matrix and formed microstructure-sized holes in the film. The FT-IR results revealed the formation of robust hydrogen bonds between the film components, indicating successful encapsulation of the CEO within the film. Furthermore, the incorporation of CEO-PE enhanced the film's mechanical and thermal stability, reduced the water vapor transmission rate, improved the film's DPPH radical scavenging and bacterial inhibition abilities, and imparted slow-release properties. Moreover, the prepared CS/SF/PE films had good degradation ability, which were basically decomposed by microorganisms within 14 d. And a life cycle assessment revealed that the CS/SF/PE film production reduces fossil resource consumption by more than 68% and global warming by more than 34% compared to film sourced from petroleum. In summary, this research demonstrated that CNC obtained from RRP can be successfully prepared as CEO-PE and combined with CS/SF matrix to prepare active food packaging film, which was promising films for extending the shelf life of fresh fruits.

Deep Eutectic Solvents as New Extraction Media for Flavonoids in Mung Bean.

Mung beans contain abundant flavonoids like vitexin and isovitexin, which contribute to their strong bioactivities, such as antioxidant effects, so efforts should focus on extracting bioactive flavonoids as well as aligning with the goal of green extraction for specific applications. Deep eutectic solvent coupled with ultrasound-assisted extraction (DES-UAE) was applied to extract flavonoids from mung beans, and eight different DESs were compared on the extraction yield. In addition, the traditional extraction method with 30% ethanol was performed as the reference. The results showed that ethylene glycol-glycolic acid achieved the highest yield among all the DESs, 1.6 times that of the reference values. Furthermore, the DES-UAE parameters were optimized as a 60 mL/g liquid-solid ratio, 30% water content in DES, 200 W ultrasonic power, 67 °C ultrasonic temperature, and 10 min extraction time, leading to the DES extract with the maximum extraction yield of 2339.45 ± 42.98 μg/g, and the significantly stronger DPPH and ABTS radical scavenging ability than the traditional extract. Therefore, employing DES and ultrasonic extraction together offers a green method for extracting flavonoids from mung beans, advancing the development and utilization of plant-derived effective components in a sustainable manner.

African pear (Dacryodes edulis) pulp antioxidants and bioactive compounds: Outcome of heat treatment

The study was aimed at evaluating the effect of heat treatment (boiling and roasting) on the antioxidant properties and phytochemical profile of African pear pulp. African pear was subjected to boiling and roasting treatment at 100 °C for 5 mins and 150 °C for 10 mins respectively. The raw, boiled, and roasted pears were analysed for antioxidants and phytochemicals were profiled using HPLC. The results of antioxidants showed that total phenols (mg GAE/g) decreased by 34 % in the boiled pears and by 18 % in the roasted pears; total flavonoids (Rutin equivalent) decreased by 50 % in the boiled pear while it was not significantly affected by roasting; DPPH radical scavenging abilities decreased from 84.15 % to 50.82 % and from 84.15 % to 57.04 % in the boiled and roasted pears. Beta-carotene was found to decrease by 17 % and 64 % in the boiled and roasted pears. HPLC quantification of phytochemicals revealed Beta Caryophyllene as the most abundant in the raw and heat-treated pears though heat treatment increased all the phytochemicals quantified. Roasting was found to significantly increase all the bioactive compounds quantified. This suggests that the roasted pear will contribute to better nutrition and health security when consumed compared to the boiled pear.

Quality Characteristics of Butter Sponge Cakes Added with Whey Protein Concentrate (WPC)

This study investigated the quality characteristics of butter sponge cakes added with whey protein concentrate (WPC)(0%, 10%, 30%, 50%, 100%) added as a fat substitute. The density of the dough of butter sponge cakes significantly increased with higher levels of added WPC and the pH decreased (<i>F</i> =248.38, <i>p</i> <.001). The moisture content also decreased significantly (<i>F</i> =3.151, <i>p</i> < .05). However, the volume (<i>F</i> =9.556, <i>p</i> <.01) and specific volume (<i>F</i> =11.15, <i>p</i> <.001) significantly increased. With respect to color, there was no significant difference in the lightness (L) value of the crumb, but the redness (a) value increased significantly with higher levels of added WPC (<i>F</i> =12.616, <i>p</i> < .001), while the yellowness (b) value decreased significantly (<i>F</i> =4.550, <i>p</i> <.01). Regarding the crust, the L values (<i>F</i> =3.791, <i>p</i> <.01) and b values (<i>F</i> =7.000, <i>p</i> <.001) decreased significantly with higher levels of added WPC, while the (a) values increased significantly (<i>F</i> =4.706, <i>p</i> <.01). The DPPH radical scavenging ability of the raw WPC used in the manufacture of butter sponge cakes was found to be 27.45%, but this increased significantly as the amount of WPC added to butter sponge cakes increased (<i>F</i> =45.237, <i>p</i> <.001). In a consumer preference test, the flavor, appearance, texture, odor, and overall acceptability were highest in the case of WPC-10 when taking advantage of the functional advantages of WPC as a lowfat substitute, confirming the development potential and optimal amount of WPC that should be added to butter sponge cakes.

Preparation and characterization of whey protein isolate-dextran-proanthocyanidins ternary complexes: Formation mechanism, physicochemical stability

The present study aimed to improve the stability and antioxidant properties of whey protein isolate (WPI) in food emulsion systems. A whey protein isolate-dextran (D) binary complex (GF) was prepared using wet Melad reaction. Based on this, a ternary complex (GF-PC) system of whey protein isolate-dextran-proanthocyanidins (PC) was constructed. The interaction mechanism and functional properties of this ternary system were investigated by turbidity, Fourier infrared, and fluorescence spectroscopy, as well as DPPH radical scavenging ability. Results showed that a novel ternary composite system was successfully constructed. The maximum encapsulation efficiency of PC was 93.09% when using the GF-0.4 PC complex (the mass ratio of GF to PC was 1:0.4). Turbidity, fluorescence spectroscopy, and FTIR spectroscopy analyses showed that PC was successfully encapsulated by GF and formed the ternary complex. SDS-PAGE and interaction forces showed that the noncovalent contacts increased significantly, while covalent interactions remained the main interaction between WPI, D, and PC. The GF-PC ternary complexes significantly improved emulsification properties and free radical scavenging ability compared to single WPI and GF conjugates. This study suggested that GF-PC could be used as a delivery system for functional active ingredients with enhanced emulsifying activity and antioxidant capacity.

Antioxidant, Anti-inflammatory, and Anti-wrinkle Effects of Sargassum horneri Extract in vitro

Purpose: This study mainly aimed to confirm the antioxidant activity, antiinflammatory, and collagen production enhancement effects of the <i>Sargassum horneri</i> (SH) extract.Methods: The measurement of the total flavonoid and total polyphenol content, 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities confirmed the antioxidant efficacy of the SH extract. The expression level of interleukin 6 (IL-6) and its upstream mechanism pathway, mitogen-activated protein kinases (MAPK), were evaluated for anti-inflammatory efficacy in human dermal fibroblast (HDF) cells. The collagenase and elastase levels were measured in terms of the ability to inhibit collagen degradation. On the contrary, collagen type 1 (COL1) and matrix metallopeptidase 1 (MMP1) were conducted to confirm the collagen production ability.Results: The DPPH and ABTS radical scavenging abilities of the SH extract were 86.87%±12% and 76.49%±2.94%, respectively, at the highest concentration of 1000 μg/mL, confirming 51.62±1.945 and 79.65±4.732 mg/g of total polyphenol and total flavonoid, respectively, which are known to have antioxidant effects. The anti-inflammatory effect of SH in HDF cells was reduced by up to 56.8% compared to the control group due to a significant decrease in MAPK. The SH extract significantly reduced collagenase and elastase, thereby inhibiting collagen degradation. On the contrary, increasing COL1 and decreasing MMP1 in HDF cells confirmed collagen production.Conclusion: Therefore, SH extract is a potential functional cosmetic through its antioxidant, anti-inflammatory, and collagen degradation inhibitory activities.

Characterisation of a novel metalloprotease produced by Bacillus subtilis JQ-2 and casein-derived bioactive peptides by the protease

A novel protease JQ-2 produced by Bacillus subtilis JQ-2, was purified and identified to be a peptidase M28 family alkaline metalloprotease with optimum pH and temperature of 11.0 and 52 °C, respectively. SDS-PAGE revealed high proteolytic activity of JQ-2 for κ-casein, and the cleavage site was identified to be at Lys111–Lys112. Ultrafiltration of the casein hydrolysate resulted in U1 fraction (>3 kDa) with good α-glucosidase inhibition ability and U2 fraction (<3 kDa) with good DPPH radical scavenging ability. Identification of the U2 fraction by mass spectrometry revealed three potential new bioactive peptides SLPQNIPP, GLPQEVLN and AVPYPQRDMPIQAF, which were verified by chemical synthesis. Among them, AVPYPQRDMPIQAF had the strongest DPPH radical scavenging ability and α-glucosidase inhibitory activity. The present study demonstrated a novel microbial protease capable of hydrolysing casein to produce new bioactive peptides with potential application in functional dairy products.

Effects of thermal treatment on foam properties and simulated in vitro digestion properties of α‐lactalbumin–tea saponin complex

In this experiment, changes in properties of α‐lactalbumin (α‐LA)‐tea saponin (TS) complex were analysed and compared after two heating temperature (65 °C for 30 min and 90 °C for 10 min). The results showed that thermal treatment can improve foaming ability, DPPH radical scavenging ability, digestibility, degree of hydrolysis and bioaccessibility of α‐LA‐TS complex. Furthermore, the addition of TS was beneficial to the foaming ability and DPPH radical scavenging ability after digestion of α‐LA and has a certain inhibitory effect on the in vitro digestibility. This study provided a theoretical basis for the application of α‐LA‐TS complex in heat‐processed food products.

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.

Preparation, structural characterization and in vitro activity of ginger polysaccharide

AbstractA polysaccharide was extracted from the fresh ginger by water extraction and alcohol precipitation. A homogeneous polysaccharide was obtained by Sevage deproteinization, dialysis, DEAE-52 ion exchange chromatography and Sephadex G-100 gel column chromatography. The molecular weight of the ginger polysaccharide was determined by high performance gel permeation chromatography. The monosaccharide composition, scanning electron microscope and other physicochemical parameters of the ginger polysaccharide were further determined. The spectral properties of the ginger polysaccharide were investigated by ultraviolet and infrared spectroscopy. On this basis, methylation analysis, 1D and 2D NMR analysis were used to investigate its possible chemical structure. The results showed that the ginger polysaccharide group was divided into neutral polysaccharide components with high homogeneity, Mw = 35.52 kDa, Mn = 216.56 kDa and the sugar content was 93.5%. The ginger polysaccharide is mainly composed of Fuc, Ara, Rha, Gal, Glc, Xyl, Man, Gal-UA and Glc-UA, the amount of substance ratio was 1.01:1.96:9.54:14.82:64.20:3.84:2.07:1.41:1.16. To study the structure–activity relationship of ginger polysaccharide, acetylated ginger polysaccharide and phosphate ginger polysaccharide were prepared by chemical methods in this study. The results of antioxidant activity in vitro showed that the ginger polysaccharide and its derivatives had good biological activity in freeing ABTS + radical scavenging, freeing hydroxyl radical scavenging, freeing DPPH radical scavenging and reducing ability. Interestingly, the results showed that the ginger polysaccharide had a certain inhibitory effect on the growth of E. coli in vitro. In general, this study provides a certain experimental basis and reference for the further research on the activity of ginger polysaccharide and its derivatives. Graphical Abstract

Effects of electron beam irradiation on microbial contamination and quality of Astragali Radix

In this study, astragali radix (AR) was irradiated at doses of 3, 5, 7, 10 and 18 kGy of electron-beam, to investigate the effects on the microbial content, physicochemical quality, and antioxidant activity. Results showed that AR was decontaminated at 7 kGy irradiation, but its color was altered. The total flavonoid, total phenol content, DPPH and ABTS radical scavenging ability increased with an increase in radiation dose for AR. In conclusion, electron beam irradiation can effectively kill the surface microorganisms of AR, increase the contents of flavonoids and total phenols, and increase its free radical scavenging activity without affecting its main active components.

The antioxidant activity, total phenolic and monomeric anthocyanin content of &lt;em&gt;Gymnema sylvestre&lt;/em&gt; leaf aqueous extract

The Gymnema sylvestre is a widely recognized medicinal plant, particularly for its effectiveness in treating diabetes. Aim of this study is to measure the antioxidant property, polyphenol and anthocyanin content of G. sylvestre aqueous extract using various in-vitro techniques. The aqueous extract was prepared and total phenolic compounds (TPC), DPPH (2,2-Diphenyl-1-Picrylhydrazyl) radical scavenging ability, total antioxidant activity using ferric reducing antioxidant power (FRAP), ferric reducing power and monomeric anthocyanin content were estimated. Correlation analyses were performed for TPC and anthocyanin against the antioxidant activity. The TPC was 4.55±0.34 mg g-1 of fresh leaf weight (FLW) and the IC50 value for DPPH radical scavenging ability was 2.40 mg mL-1 of leaf extract concentration. The percentage of inhibition strongly correlated (R2 = 0.99) with the concentration of the leaf extract. The total antioxidant power of the leaf extract was 21.06±1.74 μmol g-1 of FLW.The ferric-reducing power showed a positive correlation with the leaf concentration (R2 = 0.99). The anthocyanin content of the leaf extract was 167.84±1.45 mg per 100 g of leaf. The TPC and anthocyanin exhibited strong positive correlations with total antioxidants and DPPH, but a weak correlation with reducing power. The antioxidant properties of leaf extract could be ascribed to the presence of TPC and anthocyanin as it showed a strong correlation with antioxidant activity. This is the first study that reported the anthocyanin content of G. sylvestre leaf extract. This study found G. sylvestre leaf water extract has antioxidant properties and contains a significant amount of TPC and monomeric anthocyanin.

LC/HRESI-MS/MS screening, phytochemical characterization, and in vitro antioxidant and cytotoxic potential of Jatropha integerrima Jacq. extracts

Avoiding the probable dangerous side effects of synthetic drugs, this study aims the identification of natural antioxidant and antitumor agents from J. integerrima leaf and floral extracts. A highly efficient and fast UPLC/ESI-qTOF-HRMS/MS screening has led to characterization of 30 flavonoids, i.e. 12 flavonols, 6 flavones, 3 dihydroflavonols, 4 anthocyanins (flower), 2 dihydroflavonols, and 3 isoflavones from both J. integerrima extracts. In addition, six major polyphenols were identified for the first time from leaf extract, and their structures were established as apigenin 7-O-β-d-neohesperidoside (rhoifolin, 1), apigenin 8-C-β-D-4C1-glucopyranoside (vitexin, 2), luteolin 6-C-β-D-4C1-glucopyranoside (isoorientin, 3), 6,6″-di-C-β-D-4C1-glucopyranosyl-methylene-biapigenin (Jatrophenol-I, 4), (E)-p-coumaric acid methyl ester (5), and (E)-ferulic acid methyl ester (6) with HRESI-MS and NMR analyses. The in vitro antioxidant activity of both extracts and major pure isolates was decided using DPPH, reducing power capability, FRAP, and ABTS radical scavenging assays, and their in vitro cytotoxicity was evaluated on Ehrlich ascites carcinoma cells (EACC), as well.The flower extract and compound 3 have shown the strongest antioxidant and cytotoxic effects. At low concentrations (25 µg/mL), they showed the highest DPPH radical scavenging ability (79.63 ± 0.42 and 76.20 ± 0.35%) regarding BHA (91.44 ± 0.29% at 100 µg/mL). In the parameter of absorbance, they exhibited higher reducing power ability (1.402 ± 0.025 and 1.178 ± 0.019%) than that of BHA (0.975 ± 0.013 at 100 µg/mL). Similarly, they proved superior FRAP (1427 ± 9.61 and 1377 ± 13.61 µmol Trolox/ 100 g) and highest ABTS activity (80.19 ± 0.55 and 68.38 ± 0.19%), which are higher activities compared to BHA (88.42 ± 0.24% at 100 µg/mL). Furthermore, all samples gave noticeable cytotoxicity at the same concentration (100 µg/mL), especially the flower extract and compound 3 which showed a relatively high effect on the viability of EACC (81.12 ± 0.24 and 77.21 ± 0.76 %, respectively) relative to vincristine reference drug (90.64 ± 0.39 %). Based on the findings, the extracts and isolates can be considered as potent antioxidant and cytotoxic natural agents, especially flower extract and isoorientin (3), which may supply novel insight into their likely application in pharmaceutical industries.

Comparative analysis of antioxidant, antimicrobial, and tyrosinase inhibitory activities of Centella asiatica (l.) Urb and Eichhornia crassipes (mart.) Solms

In the present study, we examined the potential biological activities of two marginal weeds, Centella asiatica (L.) Urb and Eichhornia crassipes (Mart.) solms, using various solvents (water, methanol, and ethyl acetate). The ethyl acetate and ethanol crude extracts of Centella asiatica exhibited notable antioxidant activity, as indicated by their DPPH radical scavenging ability, with values of 349.33±3.92 and 348.48±2.96 µg Vitamin C equivalents/0.01 g dry matter, respectively. These extracts effectively inhibited free radicals from DPPH at half maximal effective concentrations (EC50) of 160.46±1.62 and 1,330±25.25 µg/mL, respectively. Furthermore, the ethyl acetate crude extract of E. crassipes (Mart.) solms, demonstrated the highest content of total phenolic compounds, with 185.88 ± 2.31µg GAE/0.01 g dry matter, as determined by the Folin-Ciocalteu colorimetric assay. Additionally, the ethyl acetate extract of E. crassipes (Mart.) solms, displayed potent tyrosinase inhibitory activity, with an IC50 value of 67.93±0.82 µg/mL. Regarding antimicrobial activity, both the ethyl acetate and ethanol crude extracts of C. asiatica (L.) Urb exhibited potential against three of the seven tested bacterial strains, as determined by the agar well diffusion method. These findings highlight the significant biological activities of C. asiatica (L.) Urb and E. crassipes (Mart.) solms, extracts, suggesting their potential for various scientific applications. Further studies are necessary to explore their diverse range of potential applications.

Effect of High-Pressure Processing on the Qualities of Carrot Juice during Cold Storage.

This study examines the impact of blanching (heating at 85 °C for 60 s), high-pressure processing (HPP) (600 MPa, 3 min, 20 °C), and a combination of both blanching and HPP on the microbiological and chemical qualities, colour, and antioxidant properties of carrot juice stored at 4 °C for 15 days. In terms of microbiological quality, the total plate count (TPC), coliform bacteria, and Salmonella spp. rose rapidly in the control group (untreated) as the storage time increased. However, for the blanching group, these values climbed more gradually, surpassing the microbiological limits for juice beverages (TPC < 4 log CFU/mL, Coliform < 10 MPN/mL, and Salmonella spp. negative) on the 9 days of storage. In contrast, TPC, coliforms, and Salmonella spp. were undetectable in the HPP and blanching/HPP samples throughout the storage period. Additionally, as storage time lengthened, the pH, total soluble solids, and Hunter colour values (L, a, b) diminished in the control and blanching groups, whilst titratable acidity and browning degree intensified. However, the HPP and blanching/HPP noticeably delayed these decreases or increases. Moreover, although the total phenolic content and DPPH radical scavenging ability in the HPP samples remained relatively stable during storage and were lower compared to other groups, the β-carotene content was higher at the end of the storage period. In summary, HPP can effectively deactivate microorganisms in carrot juice, irrespective of whether blanching is applied, and can impede reductions in pH, increases in acidity, and colour changes, ultimately extending the juice's shelf life.