DPPH Values Research Articles

Discovery of selective ROCK2 inhibitors with free radical scavenging ability for the treatment of gouty arthritis.

ROCK inhibitors can inhibit IL-1β and NLRP3, and their therapeutic potential for osteoarthritis and rheumatoid arthritis has been confirmed, but their impact on gouty arthritis has not been reported yet. By hybridization the structure of Edaravone, a series of ROCK inhibitors with pyrazolone scaffold were designed and synthesized. RM-04 has acceptable selective ROCK2 inhibitory activity with an IC50 of 4.62 µM, and its IC50 values for scavenging DPPH• and ABTS•+ are 16.72 µM and 23.15 µM, respectively, which is equivalent to that of Edaravone. Furthermore, RM-04 exhibits good pharmacokinetic properties and good safety in vivo. Meanwhile, in sodium urate-induced acute gout model, RM-04 at a dose of 5mg/kg exhibited the alleviating effect approximately equivalent to that of Celecoxib, indicating that ROCKs inhibitors with antioxidation activity could reduce the damage caused by gouty arthritis.

Investigating the inhibitory effect of nettle (Urtica dioica L.) essential oil and Pickering nanoemulsion on some pathogenic bacteria inoculated into pizza cheese.

The aim of the present research was to evaluate the effect of Urtica dioica L. (nettle) essential oil (in the forms of Pickering nanoemulsion (NEO) and free (EO)) on microbial, chemical and sensory changes of pizza cheese stored at 4°C for 12days. For this purpose, Escherichia coli and Listeria monocytogenes were inoculated into pizza cheese. In all tests, the control group had the lowest score after 12days of storage. In the antimicrobial assay test in different treatments, NEO4% treatment decreased the growth of E.coli from 4 (0th day) to 3.3 log CFU/g (12th day) and the growth of L. monocytogenes from 3.8 (0th day) to 3.1 log CFU/g (12th day). The minimum inhibitory concentration (MIC) of NEO and EO for E.coli and L. monocytogenes was 0.62±0.01mg/mL. Additionally, the minimum bactericidal concentration (MBC) of EO and NEO for E. coli was 25±0.1mg/mL, and for L. monocytogenes was 1.25±0.1mg/mL. At day 12, almost all treatments (free form and nano) had relatively similar pH. In our study, the minimum and maximum value of DPPH was detected in the treatment of NEO1% (31.25±1.50%) and BHT200 (96.40±2.5%), respectively. Also, on the 12th day of the test, the NEO treatment obtained the highest score in all sensory tests (appearance & color, body & texture, odor and overall acceptability). According to the findings of the present study, Pickering emulsion form of nettle EO increases the storage period of pizza cheese.

Impact of nanoemulsion of Ajwain-cardamom essential oils on Mortadella sausage quality during chilling (4°C) storage.

Essential oils application as natural preservatives is challenging owning to low solubility and stability to harsh conditions, while incorporation of essential oils into nanoemulsion systems can effectively improve these issues. Therefore, the nanoemulsion of ajwain (C. copticum) and cardamom essential oils were fabricated through self-emulsification technique and evaluated their size, ζ-potential, antioxidative and antibacterial activities. The effect of double nanomulsion on the textural and sensorial properties of Mortadella sausage was also examined under chilling temperature (4°C). Our goal was to improve the chilling storage of Mortadella sausage by using ajwain and cardamom nanoemulsion as natural preservative. By increasing the ajwain essential oil in the nanoemulsion, the protein and moisture of sausage increased, while the fat content decreased (17%). Furthermore, nanoemulsion of ajwain and cardamom essential oils showed particle size less than 100nm and PDI<0.5 revealing the stability of nanoemulsions. Moreover, double nanoemulsions exhibited higher antibacterial activity against S. aureus and IC50 DPPH value (107ppm). The nanoemulsion had a greater effect on the textural properties of Mortadella, reduction in hardness (∼5300g), and chewiness (∼2500gmm). Ajwain/cardamom nanoemulsion also increased the sensory properties, particularly taste and acceptance of the Mortadella. Consequently, Ajwain/cardamom nanoemulsion not only improve the storage of mortadella sausage at chilling temperature due to their antioxidant and antimicrobial properties, but also has a positive effect on the red color and textural properties created a special herbal aroma, taste and odor in the Mortadella samples, which ultimately contributed to the customer-friendly product. The appropriate dose of these nanoemulsion can develop meat products at lowest amount of nitrite in Mortadella sausage formulations, although, further research should be conducted on the mechanism of action AEO/CEO nanoemulsion concerning appearance and nitrite reduction in the meat products.

Omega-3 Fatty Acids, Lecithin, Sterols, Vitamins and Lipid Oxidation of Olein and Super Olein Fractions of Fish Oil Produced by Winterization.

To concentrate omega-3 fatty acids (n-3) in fish oil (FO), olein and super olein fraction (OF) of FO were produced by winterization. For this purpose, FO was slowly cooled to -50°C (24 h), the mixture of crystallized and non-crystallized phases was separated, filtrate was coded as OF (yield 32%), 35% of OF was kept for storage study and analytical purpose, remaining 65% was further slowly cooled down to -75°C (24 h) and filtered, filtrate was coded as super olein (SF, yield 23%). GC-MS analysis showed that unsaturated fatty acids increased due to successive winterization. In OF, C18:1, C18:2, C18:3, C20:1, C20:5 (EPA), C22:1, C22:2 and C22:6 (DHA) increased to 7.85%, 19.52%, 54.16%, 17.82%, 16.31%, 41.02%, 32.43%, and 29.89% than parent FO. In SF, C18:1, C18:2, C18:3, C20:1, C20:5, C22:1, C22:2 and C22:6 increased to 9.84%, 24.35%, 61.09%, 32.10%, 39.96%, 56.81%, 39.02%, and 48.94% than parent FO. Total phenolic contents (TPC)of FO, OF, and SF were 6.59, 12.67 and 19.72 (mgGAE/mL). Lecithin content of FO, OF, and SF were 1.29%, 0.575%, and 0.19%. In SF, desmosterol, cholesterol, stigma sterol and sitosterol were 91.57, 22.51, 12.67 and 112.18 mg/100 g. Total antioxidant capacity (TAC) of FO, OF, and SF was 49.32%, 64.27%, and 85.47%. DPPH values of FO, OF, and SF were 32.14%, 39.87%, and 46.41%. Winterization significantly raised vitamin A and E in OF and SF; vitamin A content in FO, OF, and SF (0-day) were 46.28, 67.94, and 116.48 IU; vitamin E content in FO, OF, and SF (0-day) were 1238.95, 1897.65, and 2375.11 mg/100 g. At 0-day, peroxide value (POV) of FO, OF and SF was 0.22, 0.24 and 0.25 (MeqO2/Kg) with no variation in sensory characteristics. The results of this study proved that n-3 could be increased in olein and super OFs of FO with reasonable oxidative stability.

Spatial specificity of radical scavenging ability in Moringa oleifera varieties from selected countries

Moringa oleifera (MO) is widely recognized for its rich content of bioactive compounds, which possess significant antioxidant and anti-inflammatory properties. However, variations in the phytochemical composition of MO seeds, influenced by geographical origin and processing methods, have not been fully explored. This study investigates the radical scavenging abilities of MO seeds from Nigeria, Ghana, Haiti, and India, all grown under controlled conditions at the Winfred Thomas Agricultural Research Station (WTARS) at Alabama A and M University. The primary objective of this study was to assess the variation in radical scavenging abilities, specifically DPPH (1,1-diphenyl-2-picrylhydrazyl) activity, across different MO seed varieties and processing methods. This was done to determine if spatially specific dose-response behaviors exist and to identify which combinations of seed origin and preparation yield the highest antioxidant activity. MO seeds were collected from four countries: Nigeria, Ghana, Haiti, and India, and subjected to three different processing methods—raw, boiled, and fermented. The seeds were then extracted using two solvents, 70% ethanol and 80% methanol. The DPPH radical scavenging activity was measured using the Brand-Williams method with slight modifications, and the results were expressed as micromoles of Trolox Equivalent (TE) per gram of sample. The study revealed significant variability in the antioxidant activity of MO seeds based on their geographical origin and processing methods. Among the four countries, MO seeds from India exhibited the highest average DPPH value (8018.87 µmol/g), followed by Haiti (6741.10 µmol/g), Nigeria (6349.98 µmol/g), and Ghana (6068.87 µmol/g). Raw seeds consistently showed the highest radical scavenging ability across all locations and solvents, with the highest recorded value in Haitian raw seeds extracted with 70% ethanol (9720 µmol/g). In contrast, fermented seeds exhibited the lowest antioxidant activity, with the least value observed in Ghanaian seeds extracted with 80% methanol (306.33 µmol/g). The choice of solvent also played a crucial role, with 70% ethanol outperforming 80% methanol in preserving or extracting antioxidants, particularly in raw and boiled seeds. The study also found significant dose-response relationships, with raw seeds showing the steepest increase in DPPH activity with higher extract concentrations. In contrast, fermented seeds demonstrated a weaker dose-response, indicating diminished radical scavenging ability after fermentation. The ANOVA results further highlighted the significant effects of the country of origin, treatment method, and their interaction on antioxidant activity. The interaction between geographical origin and processing methods was particularly noteworthy, suggesting that the optimal method for maximizing antioxidant activity varies depending on the seed's origin. The findings underscore the importance of considering both the geographical origin and the processing method when evaluating the antioxidant properties of MO seeds. Indian and Haitian MO seeds, particularly in their raw form and extracted with 70% ethanol, offer the highest antioxidant potential. The study also demonstrates that minimal processing is crucial for preserving the radical scavenging ability of MO seeds. Further research should focus on the specific phytochemical compounds responsible for the antioxidant activity in MO seeds from different regions. Additionally, farmers and producers should optimize cultivation and processing methods based on local environmental conditions to maximize the nutritional and medicinal benefits of MO seeds. Finally, public awareness programs should be initiated to promote the health benefits of MO seeds, particularly those with high antioxidant activity.

Evaluation of Whitening Effects and Identification of Potentially Active Compounds Based on Untargeted Metabolomic Analysis in Different Chrysanthemum Cultivar Extracts.

Chrysanthemum is a traditional Chinese medicinal herb. Chrysanthemum extracts are rich in bioactive compounds; however, there are few reports evaluating the whitening effects of organic chrysanthemum extracts. This study assessed the antioxidant and whitening effects of organic extracts from the petals of five chrysanthemum cultivars from Guangdong, China. Significant differences were observed among the five cultivars across various parameters, including IC50 values for tyrosinase inhibition activity, DPPH and ABTS values, UV absorption, and SPF values. Additionally, there were notable variations in total flavonoid, total phenolic, and chlorogenic acid contents. The BJ cultivar extract exhibited strong antioxidant capacity and superior whitening effects, containing the highest levels of total flavonoids, total phenolics, and chlorogenic acid. Correlation analysis indicated a significant relationship between total flavonoid content and IC50 of DPPH, and between chlorogenic acid and both IC50 of ABTS and SPF. Untargeted metabolomic analysis of three representative cultivars (BJ, WYHJ, and JSHJ) identified 22 compounds potentially related to antioxidant and whitening effects. Compounds significantly correlated with multiple antioxidant or whitening indicators (p < 0.05, r > 0.8) included tangeritin, hydroquinone, eupatilin, quercetin 3-(6″-malonyl-glucoside), biochanin A, and cyanidin 3-glucoside. These compounds may play crucial roles in the antioxidant and whitening effects of chrysanthemum extracts. The results highlight the promising antioxidant and whitening properties of chrysanthemum extracts, with certain genotypes, such as BJ, showing potential as superior raw material sources.

Phytochemical profile and biological screening of two Amaranthaceae plants: Atriplex halimus and Haloxylon scoparium

In this study, phytochemical and biological properties of Atriplex halimus and Haloxylon scoparium leaves, collected in Algeria, were evaluated. The aqueous extract of the studied plants was subjected to phytochemical screening by biochemical analysis and HPLC. The diffusion assay was assessed to investigate the antimicrobial effect against clinical and reference strains. Moreover, we investigated DPPH and FRAP, as well as the haemolytic activity. The results showed abundance in the phytochemical and mineral components. Notably, A. halimus exhibited the highest DPPH and FRAP values with IC50 = 1.69 ± 0.67 and IC50 = 3.20 ± 0.04 mg/g, respectively. The antibacterial activity was better at the concentration of 25 mg/mL, compared to the standard antibiotics. The inhibition zones varied between 8 and 40 mm. The haemolytic activity did not depict any toxicity. The investigated plants exhibited interesting antioxidant and antibacterial properties and may serve as a valuable source for novel antimicrobial drugs.

Gallic Acid-Encapsulated PAMAM Dendrimers as an Antioxidant Delivery System for Controlled Release and Reduced Cytotoxicity against ARPE-19 Cells.

Poly(amidoamine) (PAMAM) dendrimers have gained significant attention in various research fields, particularly in medicinal compound delivery. Their versatility lies in their ability to conjugate with functional molecules on their surfaces and encapsulate small molecules, making them suitable for diverse applications. Gallic acid is a potent antioxidant compound that has garnered considerable interest in recent years. Our research aims to investigate if the gallic acid-encapsulated PAMAM dendrimer generations 4 (G4(OH)-Ga) and 5 (G5(OH)-Ga) could enhance radical scavenging, which could potentially slow down the progression of age-related macular degeneration (AMD). Encapsulation of gallic acid in PAMAM dendrimers is a feasible alternative to prevent its degradation and toxicity. In vitro investigation of antioxidant activity was carried out using the DPPH and ABTS radical scavenging assays, as well as the FRAP assay. The IC50 values for DPPH and ABTS assays were determined through nonlinear dose-response curves, correlating the inhibition percentage with the concentration (μg/mL) of the sample and the concentration (μM) of gallic acid within each sample. G4(OH)-Ga and G5(OH)-Ga possess significant antioxidant activities as determined by the DPPH, ABTS, and FRAP assays. Moreover, gallic acid-encapsulated PAMAM dendrimers inhibit H2O2-induced reactive oxygen species (ROS) production in the human retinal pigment epithelium ARPE-19 cells, thereby improving antioxidant characteristics and potentially retarding AMD progression caused by ROS. In an evaluation of cell viability of ARPE-19 cells using the MTT assay, G4(OH)-Ga was found to reduce cytotoxic effects on ARPE-19 cells.

Caviar extract inhibitsskin photoaging by activating skin stem cells through NF-κB/MMPs/COL17A1 axis.

Ultraviolet radiations (UVR) produce harmful entities and reactive oxygen species (ROS) in skin cells, leading to skin photoaging. Caviar extract(CE) showed outstanding effects in delaying skin aging, but the underlying mechanism remains largely unknown. In this study, we prepared CE with acid protease and examined the anti-skin photoaging effects. The results showed that CE performed no cytotoxicity to HaCaT cells. For antioxidant properties, the EC50 values of DPPH and ABTS radical scavenging activity for CE were 1.27 and 5.20 mg/mL, respectively. It significantly reduced NF-κB, MMP-3 and MMP-9 protein expression levels, and increased IκB and TIMP-1 expression level in UVA-irradiated HaCaT cells. In the skin aging mice model, CE reduced the degree of UV-induced skin photoaging. Histological study confirmed that CE can ameliorate the adverse effects of UV exposure on the skin. Moreover, we found that CE could enhance the activities of Superoxide dismutase (SOD), and increased the contents of hydroxyproline (HYP) in photoaged mice skin. And CE elevated the protein expression level of COL17A1, KRT10, and KRT14 in mice skin. Taken together, our results bright systemic and new insights of CE into preventing UV-induced skin photoaging.

Construction and characterization of Laminaria polysaccharide functionalized selenium nanoparticles based on an activity-oriented approach

Laminaria polysaccharides (LP) have been shown to effectively stabilize selenium nanoparticles (SeNPs), forming LP–SeNP complexes with enhanced bioactivity. However, the correlation between their bioactivity and physicochemical properties remains inadequately explored. This study used chemical reduction with LP as stabilizer to investigate how LP-to-selenium mass ratio (LPSMR), reaction time, and temperature influence particle size, selenium content, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of LP–SeNPs. The results showed that enhanced DPPH scavenging correlated with higher selenium content and smaller particle size, primarily modulated by LPSMR and temperature. Under optimal conditions (LPSMR of 1; temperature of 25°C), the resulting LP–SeNPs exhibited uniform morphology with a particle size of 81.41nm and selenium content of 653.91mg/g. This stability was achieved through non-covalent interactions between LP and SeNPs, providing superior light and acid resistance compared to unmodified SeNPs. Notably, LP–SeNPs showed synergistic antioxidant effects, with lower half-maximal inhibitory concentration (IC50) values for scavenging DPPH, hydroxyl, and superoxide anion radicals than LP or SeNPs alone, and enhanced hypoglycemic activity. Cytotoxicity assays confirmed LP–SeNPs had reduced toxicity compared to Na2SeO3 and selenopeptide. These findings provide insights into the structure-activity relationships of LP–SeNPs and support their potential application as antioxidant and hypoglycemic agents.

Comprehensive analysis of primary and secondary metabolites and antioxidant activities provides insights into metabolic profiling of different organs of Pimpinella brachycarpa Nakai.

Pimpinella brachycarpa Nakai is a perennial plant that has been widely used as a traditional medicine. However, the comprehensive analysis of primary and secondary metabolites and antioxidant activities in different organs (flowers, leaves, stems, and roots) has not been extensively studied. A comprehensive analysis using GC-qMS, GC-TOFMS, and HPLC metabolomic analyses identified 66 known metabolites in different organs of P. brachycarpa. The heat map showed that most metabolites were high in flowers and leaves. KEGG enrichment analysis based on plant metabolic pathways showed that six pathways were significantly impacted based on -log p-value and pathway impact scores. The in vitro antioxidant activities, such as DPPH, ABTS, and SOD-like, reducing power activities, IC50 values for DPPH, ABTS, and SOD were highest in flower and leaf extracts. This study elucidated the metabolites and medicinal and edible value of different P. brachycarpa organs, promoting the effective utilisation of different P. brachycarpa organs.

Optimizing Polyphenolic Extraction from Wild Guava Leaves: A Response Surface Methodology Approach to Antioxidant and α-Glucosidase Inhibitory Activities

Objective Elevated concentrations of total phenolic content (TPC) and total flavonoid content (TFC) in extracts from wild Psidium guajava L. leaves are associated with their antioxidant and α-glucosidase inhibitory activities. This study aimed to determine the optimal ultrasound-assisted extraction conditions to maximize TPC, TFC yield, as well as antioxidant and α-glucosidase inhibitory potential. Methods The central composite design (CCD) of Response Surface Methodology (RSM) was employed for empirical model development with three levels of factors, including ethanol concentration (33.18 to 66.82% in distilled water), extraction time (1.59 to 18.41 min) and solvent-to-solid ratio (5.79 to 14.20 mL/g). Results The results indicated that under optimal conditions, the total phenolic content (TPC) and total flavonoid content (TFC) values were 152.954 mg GAE/g DW and 113.871 mg QE/g DW, respectively. These conditions included an ethanol concentration of 51.94%, an extraction time of 9.56 min, and a solvent-to-solid ratio (v/w) of 10.84 mL/g. Furthermore, the maximum values for DPPH and ABTS radical scavenging activities were 124.990 mg TE/g DW and 194.730 mg TE/g DW, respectively and the lowest IC50 for α-glucosidase inhibitory activity recorded at 11.946 µg/mL. The validated models exhibited strong consistency between the predicted and experimental values, with variations of less than 5% under optimal conditions. Additionally, Principal Component Analysis (PCA) also confirmed the appropriate model to predict the extraction yield of total polyphenol and flavonoid content, as well as their biological activities, including DPPH and ABTS radical scavenging and alpha-glucosidase inhibitory activities. Conclusions The enhancement of antioxidant and antidiabetic extraction processes in both the pharmaceutical and food industries through the use of ultrasound-assisted extraction from Wild Guava leaves can increase production to meet high demand. This efficiency is particularly noteworthy, as it demonstrates the advantages of using ultrasound in the extraction process.

Phenolic content and antioxidant activity of Croatian and German honey.

Since honey has a therapeutic role in the treatment of many diseases, we investigated the content of phenolic compounds and the antioxidant activity in acacia (Robinia pseudoacacia L.), chestnut (Castanea sativa Mill.) and lime-tree (Tilia spp.) honey originating from Croatia and Germany. Total phenols, flavonols, and flavanols contents were observed at higher levels in Croatian Castanea honey compared to German Castanea honey. Significant higher values of total flavanols and hydroxycinnamic acids were measured in Croatian Tilia honey compared to German Tilia honey. For Robinia honey, significantly higher values of total phenols and flavonols were observed in almost all Croatian honey samples compared to German honey. Croatian honey samples had higher antioxidant activity compared to German honey samples with most tested methods. The highest total phenols, total flavanols, ABTS, DPPH, and FRAP values were measured in Castanea honey, then in Robinia honey, and the lowest values in Tilia honey samples. With new developed HPLC method, pinobanksin, pinocembrin, and chrysin were identified in the majority of honey samples. Our results imply that both botanical and geographical origin influence the final quality of phenolic compounds and antioxidant activity in honey. A high positive correlation between the results of antioxidant activity and polyphenols was detected.

Influence of nitrogen treatments on some nutrient concentration and bioactive compounds of broccoli.

Nitrogen fertilization in broccoli is very important for plant growth and productivity. However, it is known that the nitrogen source of the nitrogen fertilizer is also effective on quality parameters. In this study we investigated the effects of different nitrogen sources (ammonium sulphate and calcium nitrate) on bioactive compounds and leaf nutrients of broccoli cultivars (Monet, Italian and Karadede). The highest total phenolic content was 0.24 mg g- 1 fw in cultivar Monet. Nitrate-based fertilizer treatments provided higher total phenolic (0.28 mg g- 1 fw) and flavonoid (0.56 mg g1 fw) contents and FRAP (0.24 mmol g- 1 fw) values compared to ammonium-based fertilizer treatments. On the other hand, DPPH (0.77 mmol g- 1 fw) values were higher in the ammonium nitrogen treatments. Among the cultivars, Monet had the highest total phenolics, flavonoids and FRAP values. When leaf nutrient concentrations were analyzed, ammonium sulfate application resulted in higher sulfur (0.86%), zinc (20.72mg kg- 1) and manganese (28.80mg kg- 1) concentrations compared to calcium nitrate. Calcium nitrate treatment provided the highest calcium (2.09%) and iron (37.50mg kg- 1) concentration in Monet cultivar. Phosphorus (0.31-0.35%) and magnesium (0.073-0.084%) concentrations differed among cultivars. In conclusion, the choice of nitrogen source and cultivar in broccoli cultivation plays an important role in the bioactive compound profile and nutrient composition of the broccoli crop. The results provide useful information for the improvement of broccoli quality.

Characterization of 'borde': A traditional ethiopian cereal-based fermented beverage - Microbial analysis, rheological profiling, and functional attributes

The study focused on the characterization of an Ethiopian traditional beverage, borde, produced by lactic acid bacteria (LAB) and yeast through natural fermentation. Samples were collected from three distinct locations in Ethiopia and subjected to analyses encompassing microbiological, antioxidant, enzyme inhibition, rheological and physicochemical aspects. The early stages of fermentation exhibited prevalence of Enterobacteriaceae and aerobic mesophilic bacteria. Towards the end of fermentation, yeast (6.07–6.72) and LAB (6.52–7.12) (log CFU mL−1) dominated the microbiological profile of all borde samples. Significant difference (P < 0.05) in the number of microorganisms were noted between the samples. Antioxidant activities, assessed through DPPH and ABTS values, ranged between 51.5 and 64.6 % and 47.4–62.9.1 %, respectively. The average value of α-glucosidase and pancreatic lipase inhibition for borde samples were ranged from 36.56 to 43.23 % and 31.08–40.19 %, respectively. Rheological investigations indicated pseudoplastic fluid behavior, as evidenced by the decreasing apparent viscosity values with shear rate. Moreover, the samples displayed solid-like structures, with lower loss modulus (G″) values compared to storage modulus (G′). The shared physicochemical characteristics and the dominance of specific microbial groups suggest the potential for developing a direct fermentation system for this traditional cereal-based beverage. Overall, these findings contribute valuable insights into the multifaceted nature of borde, paving the way for further advancements in its production and quality control.

Development of konjac glucomannan-based active-intelligent emulsion films loaded with different curcumin-metal chelates: Stability, antioxidant, fresh-keeping and freshness detection properties

The aim of this study was to develop konjac glucomannan (KGM)-based active-intelligent emulsion films loaded with different curcumin-metal chelates, where six types of films were prepared and their corresponding properties were investigated. The FTIR and XRD results showed that curcumin chelated with metal ions successfully. Moreover, curcumin-Ca chelate had the best thermal stability and antioxidant activity with the DPPH and ABTS radical-scavenging activity values of 38.28 % and 22.79 %, respectively. Furthermore, the results of microstructure and contact angle showed that chelation with metal ions improved the interfacial interactions between curcumin-metal chelates and film matrix. Interestingly, KGM-based active-intelligent emulsion films loaded with curcumin-Ca chelate (Type IV film) displayed the best thermal stability with the highest temperature of maximum weight loss at 380 °C, the best mechanical property, the highest total phenol content (17.31 mg gallic acid/g film), as well as the best antioxidant activity with DPPH and ABTS radical-scavenging activity values of 69.24 % and 58.66 %, respectively, and the best antibacterial activity. Consequently, Type IV film was used for the fresh-keeping and freshness detection of pork. The results showed that the pork packaged with Type IV film displayed excellent fresh-keeping properties, including reducing the increase rate of volatile basic nitrogen (TVB-N) and pH values and the decrease rate of hardness and elasticity of pork during storage time. Meanwhile, the color of Type IV film gradually changed from yellow to red. Therefore, this study suggested that KGM-based active-intelligent emulsion films have great potential application in the fresh-keeping and freshness detection of fresh meat.

The effects of varying ingredients combination and boiling time on total phenolic content, antioxidant activity, and antimicrobial properties of lemongrass-ginger tea

This study was aimed at exploring the effect of varying lemongrass-ginger combinations, and boiling time on total phenolic contents (TPC), antioxidant activity, and antimicrobial efficacy of lemongrass-ginger tea. Lemongrass-ginger tea was produced by varying the percentage of lemongrass (25 %, 50 %, and 75 %) and boiling times (5, 10, and 15 min). The antioxidant activity of the lemongrass-ginger tea samples was investigated using the DPPH and ABTS assays whereas the TPC was determined using the Folin-Ciocalteau method. The antimicrobial activities were investigated by measuring the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) of the tea against selected microorganisms, and its combinatory effects with antimicrobial drugs. The lemongrass-ginger combination and the boiling time significantly affected antioxidant potential, TPC, and antimicrobial activities. TPC measured ranged between 966.7 ± 90.20 to 1761.3 ± 81.70 μgGAE/g whereas DPPH antioxidant activities varied from 43.97 ± 14.99 % to 75.20 ± 8.55 %. The highest values of TPC and DPPH were 1761.3 ± 81.70 μgGAE/g and 75.20 ± 8.55 % and were recorded by 75 % lemongrass-ginger combination boiled for 15 min. Furthermore, differences in lemongrass-ginger combination and boiling times resulted in varying antimicrobial activities against the test microorganisms. The lowest MBC was recorded for 50 % lemongrass boiled for 10 min against C. albicans, 75 % lemongrass boiled for 15 min against K. pneumoniae and S. typhi, and 25 % lemongrass against E. coli. Additionally, varying ingredient proportions and boiling times affected the combinatory effect of the tea with antimicrobial drugs. However, the exact effect depends on the proportion of ingredients used and the boiling times.

Phenolic compounds, antioxidant and antileishmanial activities of kombucha as affected by fermentation time

ObjectiveStudy the impact of fermentation time on the phytochemical properties, antioxidant and antileishmanial activities. Materials and methodsThe preparation of Kombucha tea by fermentation was performed under aseptic conditions and symbiotic culture of bacteria and yeast (SCOBY) layer was maintained in culture for continuous growth in a water-sugar (4 L-500 g) mixture for 7, 14, 21, 28 and 35 days. The process of preparation was performed using a decoction. Phenolic compounds, flavonoids, and tannins was determined using standard method. The antioxidant activity was determined using three tests: DPPH•, ABTS• + and FRAP methods. Finally, the antileishmanial activity was performed in vitro on Leishmania donovani promastigote strains. ResultsThe qualitative analysis of the constituents showed the kombucha drink was rich in saponins, terpenoids, quinones, phenolic compounds, catechins and coumarins depending on the fermentation times. Depending on the fermentation time (7 days, 14 days, 21 days, 28 days and 35 days), significant quantities of phenolic compounds were obtained in the tea with values ranging from 182.42 to 509.41 mg GAE/g dry extract; 15.83–53.05 mg QE/g dry extract and 6.16–51.82 mg TAE/g dry extract respectively for phenolic compounds, total flavonoids and total tannins. The SC50 values of DPPH• and ABTS•+, were 14.57 μg/mL; and 21.47 μg/mL after 14 and 21 days of fermentation respectively indicating a good antioxidant profile. The inhibition of the promastigote form of Leishmania donovani responsible for visceral leishmaniasis was observed with the samples obtained after 7 days, 14 days and 28 days with inhibitory concentrations 50 of: 131.2, 48.86 and 128.8 μg/mL respectively. The antileishmanial activity was more pronounced with the Kombucha tea after 14 days (KBT14) extract (48.86 μg/mL). ConclusionThe Kombucha tea revealed the presence of phenolic compounds at different fermentation time. In addition, a good antioxidant profile was observed with the different radicals analyzed. Also, the inhibition of the Leishmania parasite was obtained. Therefore, the Kombucha tea constitutes a source bioactive molecules with antioxidant properties against Leishmania parasite.

Antioxidant potential and xanthine oxidase inhibition of flavonol glycosides from Phyllanthus emblica L. leaves

Context: Hyperuricemia is the cause of gout in the inflammatory joint condition. The xanthine oxidase enzyme is a therapeutic target for gout treatment because it plays a role in the generation of uric acid. Allopurinol is used to treat gout. It prevents the xanthine oxidase enzyme from producing as much uric acid. When selecting a medication, one must consider the various adverse effects of allopurinol. Phyllanthus emblica plants are among the medicinal plants that can be used as an alternative treatment for gout. Aims: To evaluate isolated compounds from the Phyllanthus emblica as antihyperuricemia candidates. Methods: The isolated compounds were characterized using High-Performance Liquid Chromatography Analysis and Thin Layer Chromatography-Densitometry. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and cupric ion (CUPRAC) antioxidant capacity procedures were used to develop the antioxidant activity index. The ability to inhibit xanthine oxidase was determined using a spectrophotometer. Results: Compound 1 was indicated as rutin having antioxidant capacity with an antioxidant activity index (AAI) DPPH value of 7.89 ± 0.03 and AAI CUPRAC value of 15.83 ± 0.04 stronger than compound 2 (quercitrin) with an AAI DPPH value of 3.72 ± 0.01 and AAI CUPRAC 3.24 ± 0.03. The IC50 for quercitrin's inhibition of xanthine oxidase is 23.85 ± 2.04, which was higher than rutin’s IC50 value of 32.77 ± 4.49 µg/mL. Conclusions: Flavonol glycosides present in the ethanol extract of Phyllanthus emblica leaves gave potent xanthine oxidase inhibitory activity stronger than the extract. Quercitrin gave stronger xanthine oxidase inhibitory activity, but this compound has weaker antioxidant capacity compared to rutin.

Synthesis of Copper(I) Oxide Thin Film Through Potentiostatic Electrodeposition as an Antioxidant Film

Research on metal-based nanoparticles, such as silver, gold, and copper(I) oxide (Cu2O), has drawn considerable attention due to their potential applications in catalysis, antioxidants, antimicrobials, and anticancer fields. In this study, we successfully deposited Cu2O antioxidant films on indium tin oxide substrates through potentiostatic electrodeposition. The X-ray diffraction characterization revealed distinct peaks at 2θ value of 36.32°, 42.21°, and 61.30°, indicating the crystal structure of Cu2O thin film. The scanning electron microscopy image showed the three-sided pyramid morphology of Cu2O particles with average size of 316.18 nm. The energy dispersive X-ray spectrum confirmed the purity of the thin film, which is composed only of Cu and O elements without any impurities. The photoelectrochemical showed that the deposited Cu2O has a maximum photocurrent density of 8.37 mA/cm² under visible light irradiation and 1.40 mA/cm² without irradiation. In addition, this study also found that the highest inhibition values of DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals were observed when ascorbic acid was added.