Superoxide Radical Scavenging Activity Assay Research Articles

Molecular Identification and Phytochemical Analysis and Bioactivity Assessment of Catharanthus roseusLeaf Extract: Exploring Antioxidant Potential and Antimicrobial Activities.

Plants have long been at the main focus of the medical industry's attention due to their extensive list of biological and therapeutic properties and ethnobotanical applications. Catharanthus roseus, sometimes referred to as Nithyakalyani in Tamil, is an Apocynaceae family member used in traditional Indian medicine. It also examines the plant's potential antimicrobial and antioxidant activities as well as its preliminary phytochemical makeup. Leaf material from C. roseus was analyzed and found to include a variety of phytochemicals including alkaloids, terpenoids, flavonoids, tannins, phenols, saponins, glycosides, quinones, and steroids. Four of the seven secondary metabolic products discovered in C. roseus leaves showed bioactive principles: 3-methylmannoside, squalene, pentatriacontane, and 2,4,4-trimethyl-3-hydroxymethyl-5a-(3-methyl-but-2-enyl)-cyclohexene. Catharanthus roseus is rich in the anticancer compounds vinblastine and vincristine. Whole DNA was isolated from fresh leaves, then amplified, sequenced, and aligned to find prospective DNA barcode candidates. One DNA marker revealed the restricted genetic relationship among C. roseus based on genetic distance and phylogenetic analysis. The antioxidant activity of the plant extract was evaluated using the DPPH, ABTS, phosphomolybdenum, FRAP, and superoxide radical scavenging activity assays, while the antibacterial potential was evaluated using the agar well diffusion assay. The ethanol extract of C. roseus was found to have the highest reducing power. In addition, a 4- to 21-mm-wide zone of inhibition was seen when the C. roseus extract was tested against bacterial and fungal stains. In conclusion, C. roseus has the most promise as an antibacterial and antioxidant agent.

Preparation of l-Arginine Schiff Bases Modified Chitosan Derivatives and Their Antimicrobial and Antioxidant Properties.

We successfully prepared a series of l-arginine Schiff bases acylated chitosan derivatives, aiming to improve the antioxidant activity and antimicrobial activity of chitosan by introducing a furan ring, pyridine ring, and l-arginine structure. The accuracy of the structures of ten compounds was characterized by FT-IR and 1H NMR. In terms of DPPH radical scavenging activity, except for compound CR3PCA, the scavenging rate of other compounds was higher than chitosan, especially CRCF and CRBF had strong scavenging abilities. At the same time, in the superoxide-radical scavenging activity assay, CRCF, CRBF, CR3PCA, CR2C3PCA, and CR2B3PCA were comparable to positive control at 1.60 mg/mL. Simultaneously, CRFF, CRCF, and CRBF had a certain inhibitory effect on Botrytis cinerea. Furthermore, the inhibitory effect of CRFF, CRCF, and CR3PCA on Staphylococcus aureus was very well, close to the positive control at 1.00 mg/mL. CRCF and CR2B3PCA showed better inhibitory effects on Escherichia coli than other compounds. The MTT assay was used to determine the cytotoxicity of the chitosan derivatives, which proved their safety to fibroblast cells. In summary, the study indicated that some of these compounds have the potential for further development and utilization in the preparation of antioxidants and antimicrobial agents.

Seasonal Variations in the Chemical Composition of Liangshan Olive Leaves and Their Antioxidant and Anticancer Activities

The seasonal changes in the chemical composition of Olea europaea leaves from January to December at Liangshan (China) have been investigated. The highest total phenolic content (TPC), total flavonoid content (TFC), and free amino acid content (FAAC) levels were found in May and December, while the lowest levels were detected in April and September. The soluble protein content (SPC) and the soluble sugar content (SSC) were highest in spring but lowest in summer and winter. The levels of major phenolic compounds, including oleuropein, and luteolin-4’-O-glucoside, followed by apigenin-7-O-glucoside, quercetin, rutin, luteolin, and apigenin, increased during spring and winter but decreased during summer and autumn. In addition, phenolic extracts (PEs) showed dose-dependent antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and superoxide radical scavenging activity assays; the reducing power was tested. The anticancer activities of PE at various concentrations were assessed by a cell counting kit-8 (CCK-8), and the IC50 (50% effective concentration) to HEK293, HeLa, and S180 cells were 841.48, 7139, and 457.69 μg/mL, respectively. PE-treated S180 cells inhibited proliferation through activation of caspase-3/9 and disruption of the mitochondrial membrane potential. Thus, PE in Liangshan olive leaves possessed strong antioxidant and anticancer potential, and spring and winter were determined as optimal harvesting seasons.

Potential of antioxidant and toxicity of some medical plants used by sub-ethnic communities of Bahau in East Kalimantan

The purpose of this research is to assay the potential antioxidant and toxicity of several plants from Bahau, a sub-ethnic in East Kalimantan in regard to their utilization as traditional medicines. This research includes phytochemical analysis, DPPH radical and superoxide radical scavenging activity as well as toxicity assay using Artemiasalina shrimp larvae. The results of the extraction showed the highest yield was 2,91% obtained from avung tanaq (Ficus uncinata), while the lowest is 1.14% obtained from tevoqsalah (Saccharum sp.) species. The result of phytochemicals showed that all plants contain alkaloid and carbohydrate. While carotenoids, saponins, triterpenoids and steroids were absence in all plant extracts. The DPPH radical scavenging activity test showed that the lowest IC50 value of kayog kue (Dictamnus albus) by 23.96 μg/mL. The superoxide radical scavenging activity assay showed IC50 values of all extract samples were >100 μg/mL. The toxicity assay showed that LC50 values of all samples of extract tested were >1000 μg/mL. The present research suggested good potential activity of some plants from Bahau ethnic and further research oriented to wide uses of the plants as herbal products is needed.

Occurrence of Secondary Metabolites and Free Radical Scavenging Ability towards Better Adaptability of Some Mangrove Species in Elevated Salinity of Indian Sundarbans

Mangrove, a specialized group of plant communities, provide immense ecological and protective benefits to the coastal areas of the tropical and subtropical world where they thrive. Demographic obligation and climatic hostilities have massively altered their vegetation pattern and, even ruined some key species to large extent. The present study aims to consider Reactive Oxygen Species (ROS) scavenging skills in some degrading mangrove taxa of Indian Sundarbans (Xylocarpus granatum and Heritiera fomes) compared with some opulently growing ones (Excoecaria agallocha, Bruguiera gymnorrhiza and Phoenix paludosa) in increasing salinity gradient, in relation to their sustainability. Non-enzymatic antioxidants (secondary metabolites) Proanthocyanidin and Tannin were estimated and Free radical scavenging ability was evaluated by Singlet Oxygen Scavenging Activity Assay, Reducing power assay, effects on Peroxynitrite, Nitric Oxide Radical Scavenging, Hydrogen Peroxide Scavenging Activity Assay, Reaction with Hypochlorous Acid, Superoxide Radical Scavenging Activity Assay and Hydroxyl Radical Scavenging Activity. Relatively higher occurrence of secondary metabolites and improved antioxidant ability were recorded in E. agallocha, B. gymnorrhiza and P. paludosa; than the other two plants X. granatum and H. fomes; where the trend showed a decline in the ROS scavenging after a certain increase in salinity. Strong positive correlation of both secondary metabolites and radical scavenging ability with salinity pose the three stable taxa more viable in the higher salty environment of the Indian Sundarbans. But relatively less ROS scavenging ability in more saline zones, may be the potential reason for the unfavorable existence of the two red listed plants, which would ultimately lead to gradual natural extinction of them from the Indian Sundarbans.

Optimization of Total Polyphenols Extraction from Vigna angularis and Their Antioxidant Activities

Vigna angularis, also called adzuki bean, a member of the family Fabaceae, has long been cultivated in Asian countries. This legume has received considerable attentionowing to the presence ofpolyphenols. The optimal extraction conditions for total polyphenols from V. angularis and their antioxidant activities were investigated in this study. Ultrasound-assisted extraction was used to optimize the extraction of total polyphenols from V. angularis. Factors that influenced the extraction efficiency, such as ethanol concentration, liquid-solid ratio, and ultrasonic time were investigated by Box-Behnken design. Folin-ciocalteu colorimetry was adopted to determine the total polyphenol content by using gallic acid as a reference. Antioxidant activities of the total polyphenols were evaluated by 1,1-diphenyl-2-picrylhydrazyl, hydroxyl and superoxide radical-scavenging activity assays. The optimized extraction conditions were as follows: ethanol concentration of 44.3%; liquid-solid ratio of 21.6:1 and ultrasonic extraction time of 30 min. Under these optimal conditions, the model’s predicted extraction efficiency was 4.19 mg/g. The mathematical model had a high correlation (P<0.05) and could be employed to extract total polyphenols from V. angularis. In vitro antioxidant activity results showed that total polyphenols had strong antioxidant capacity and could be used as potential antioxidant agents. This study provided a reference for the exploration of new natural antioxidants.

Toxic essential oils. Part II: Chemical, toxicological, pharmacological and microbiological profiles of Artemisia annua L. volatiles

Botanical drugs based on Artemisia annua L. (Asteraceae) are important in the treatment of malaria. Alongside with artemisinin, this aromatic species produces high and variable amounts of other chemicals that have mostly unknown biological/pharmacological activities. Herein, we have studied the toxicological/pharmacological profile of volatile constituents of a Serbian population of A. annua. Fifty-eight components were identified, among them, artemisia ketone (35.7%), α-pinene (16.5%) and 1,8-cineole (5.5%) were the most abundant ones. Significant variability of A. annua volatile profile was confirmed by means of agglomerative hierarchical cluster analysis indicating the existence of several different A. annua chemotypes. In an attempt to connect the chemical profile of A. annua oil with its biological/toxicological effects, we have evaluated in vivo and/or in vitro toxicity (including hepato- and nephrotoxicity/protection), antinociceptive, antioxidant (DPPH, ABTS and superoxide radical scavenging activity assays), enzyme inhibiting (protein kinase A and α-amylase) and antimicrobial potential of A. annua oil and of its constituents. Our results revealed that the beneficial properties of A. annua botanical drugs are not limited only to their antimalarial properties. Taking into account its relatively low toxicity, the usage of A. annua volatiles (at least of the herein studied population) does not represent a health risk.

In vitro antioxidant activity of feruloyl arabinose isolated from maize bran by acid hydrolysis.

In this study feruloylated oligosaccharides (FOs) was released from maize bran by hydrochloric acid hydrolysis, and feruloyl arabinose (F-Ara) was obtained by D301 macroporous resin chromatography followed by polyamide resin purification from FOs. After structural identification, the antioxidant activity of F-Ara was evaluated in vitro by DPPH and superoxide radical scavenging activity assay, reducing power assay and chelating activity assay. The results show that F-Ara exhibited antioxidant activity in vitro when compared to standard antioxidants such as butylated hydroxyanisole, ferulic acid and L-ascorbic acid. The antioxidant activity depends on the concentration and increases with increasing dose of sample. The present study suggests that F-Ara possesses promising future for its strong reducing power, chelating activity and free radical-scavenging activity. Therefore, it can be a natural and efficient antioxidant used in food, medicine and cosmetic.

Evaluation of the antioxidant potential of cauliflower (Brassica oleracea) from a glucosinolate content perspective

Glucosinolates (GLSs) are of great interest for their potential as antioxidant and anticancer agents. Our aim was to assess in vitro antioxidant activity of cauliflower GLSs and their derivatives, as well as to evaluate their contribution to the overall antioxidant capacity of cauliflower extracts using four different in vitro assays, 2,2′-azino-bis-(3-ethyl-benzothiazoline-6-sulphonic acid) radical cation (ABTS+), 2,2-diphenyl-1-picrylhydrazyl assay (DPPH), oxygen radical absorbance capacity assay (ORAC) and superoxide radical scavenging activity assay (SRSA). The antioxidant activities of GLSs determined using ABTS+ and DPPH assays were weak. In contrast, ORAC and SRSA assays showed significant antioxidant activity for GLSs. This activity was particularly important for glucobrassicin, which was the most effective GLS, and for glucoiberin and gluconapin. Mixtures of GLSs did not show either synergy or antagonism in general. Interestingly, the breakdown products, i.e. enzymatic hydrolysis-derived products (EHDP) of GLSs, were far more active than the native GLSs. The highest increases in antioxidant activity were obtained for EHDPs from progoitrin, sinigrin and glucoraphanin; progoitrin EHDP being the second most active derivative behind glucobrassicin EHDP. Antioxidant activities and GLS composition of different cauliflower by-product extracts were also determined. The contribution of different GLSs on measured antioxidant activity of cauliflower extracts was also discussed.

Tert-Butylhydroquinone as a Spectroscopic Probe for the Superoxide Radical Scavenging Activity Assay of Biological Samples

As a more convenient and less costly alternative to electron spin resonance (ESR) and nonspecific nitroblue tetrazolium (NBT) and cytochrome c assays of superoxide radical (SR, O(2)(•-)) detection, a novel probe, tert-butylhydroquinone (TBHQ), is introduced for SR nonenzymatically generated in the phenazine methosulfate-β-nicotinamide adenine dinucleotide (PMS-NADH) system. SR attacks both TBHQ and SR scavengers incubated in solution for 30 min where scavengers compete with TBHQ for the O(2)(•-) produced. TBHQ, but not its O(2)(•-) oxidation product, tert-butyl-1,4-benzoquinone (TBBQ), is responsive to the CUPRAC (cupric reducing antioxidant capacity) spectrophotometric assay. The CUPRAC absorbance of the ethyl acetate extract of the incubation solution arising from the reduction of Cu(II)-neocuproine reagent by the remaining TBHQ was higher in the presence of O(2)(•-) scavengers (due to less conversion to TBBQ), the difference being correlated to the SR scavenging activity (SRSA) of the analytes. With the use of this reaction, a kinetic approach was adopted to assess the SRSA of amino acids, vitamins, and plasma and thiol antioxidants. This assay, applicable to small-molecule antioxidants and tissue homogenates, proved to be efficient for cysteine, uric acid, and bilirubin, for which the widely used NBT test is nonresponsive. Thus, conventional problems of NBT assay arising from formazan insolubility and direct reduction of NBT by tested scavengers were overcome.

Flavonoids in &lt;i&gt;Sasa senanensis&lt;/i&gt; and Their Antioxidative Activities

Studies of the antioxidative constituents in Sasa senanensis resulted in the isolation of three flavonoid glycosides from an ethyl acetate-soluble portion of a methanol extract. The structures were characterized to be 6-C-α-l-arabinoside (1), luteolin 6-C-β-d-glucoside (2) and luteolin 7-O-β-d-glucoside (3) from spectral data. The antioxidative activities of these compounds were tested by DPPH and superoxide radical scavenging activity assays, and luteolin 6-C-β-d-glucoside was shown to be the most highly potential antioxidant; the activities of all three compounds were higher than those of quercetin.

ANTIBACTERIAL, ANTIOXIDANT AND TOPOISOMERASE-I INHIBITOR ACTIVITIES OF THE COASTAL ETHNOMEDICINAL PLANT Pemphis acidula

Pemphis acidula stem bark had been used traditionally in Indonesia to treat Recurrent Aphthous Stomatitis This research was conducted to examine the biological activities of its extract as antibacterial, antioxidant and topoisomerase-I inhibitor. The latter mentioned is one of the target molecules for anticancer drug. The antibacterial activity was examined using disc diffusion assay against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Streptococcus mutans. The antioxidant activity was measured using superoxide radical scavenging activityassay. Topoisomerase-Inhibitor activity was determined using the method reported by TopoGEN. The chloroform extract did not show antibacterial activity and it has low antioxidant activity (48.5%). The ethyl acetate and methanol extracts positively inhibited the growth of target bacteria at concentration of 0.3-mg/paper disk. It also showed high antioxidant activity. At concentration of 250 µg/ml both extracts were able to scavenge superoxide free radicals which was 94.8% and 83.4% for ethyl acetate and methanol extract, respectively. The methanol extract also inhibited topoisomerase-I activity at concentration of 7.5 µg/ml. The results suggest that there is a correlation between antibacterial, antioxidant and topoisomerase-I inhibitor activity. The stem bark extracts contain biologically active compounds that could be potential for nutraceutical or pharmaceutical development.