Meniran (Phyllanthus niruri Linn.) is a medicinal plant that can reduce obesity status, hypoglycemic, hypotensive, and have antioxidant activity. Meniran has been long used as a medicinal plant, but ...its utilization in a form of water infusion is still rare. This research is a continuation study which aims to identify the biomolecules that have antioxidant activity in water infusion of meniran. The making of water infusion of meniran requires drying process, which can be done by room temperature drying and sun drying. Phenol and fl avonoid compounds in meniran are assumed to have antioxidant activity. Both compounds are easily oxidized and isomerized due to sun exposure. It is assumed that the drying method will aff ect the presence of phenol and fl avonoid compounds and its antioxidant activity. The study began with the process of sun drying and room temperature without direct sun exposure. Then the extraction process used water soxhlet by soxhlet extraction method. The extract was then tested qualitatively using the DPPH IC50 method. The results of the qualitative analysis with meniran color visualization are positive containing fl avonoids and phenols. The results of quantitative analysis of meniran which are dried by sun drying; fl avonoids 0.90% w/w and 1.65% w/w phenols, in samples stored at room temperature: 2.00% w/w fl avonoids and phenol 56.16% w/w. The antioxidant activity of IC50-DPHH in extract concentrations (2, 4, 6, 8, 10, 15, 20 ppm) of dried meniran at room temperature 18.48 ppm, sun drying cannot be determined.
Aryani F, Kusuma IW, Meliana Y, Sari NM, Kuspradini H. 2023. Potential antibacterial and antioxidant activities of ten essential oils from East Kalimantan, Indonesia. Biodiversitas 24: 665-672. This ...study aimed to evaluate ten aromatic essential oils' antibacterial and antioxidant activity. Ten aromatic herbs were distilled using the water and steam distillation method. The essential oils obtained was tested for its physical properties, color, refractive index, and specific gravity. The refractive index was measured using a refractometer. On the other hand, specific gravity was measured using a pycnometer. Antioxidant activity testing using the free radical DPPH (2,2-diphenyl-1-picrylhydrazyl) and ascorbic acid was used as the control. Antibacterial activity testing using the agar diffusion method and pathogenic bacteria, namely Salmonella typhi, Escherichia coli, Propionibacterium acnes, and Staphylococcus aureus. Chloramphenicol was used as a positive control and acetone as a negative control. The results obtained essential oils with a slightly yellowish to brownish-yellow color. The highest refractive index and specific gravities were Syzygium aromaticum oil, and the smallest was Litsea elliptica and Eucalyptus pellita oils. The results of the antioxidant activity test carried out at a concentration of 500 µg/mL range from 4.82 % to 85.06 % inhibition and showed that the highest inhibition was Cymbopogon citratus and Syzygium aromaticum by 55.76 % and 85.06%, respectively. Antibacterial activity of ten essential oils showed a varied inhibition zone (0-60 mm) against S. typhi, E. coli, P. acnes, and S. aureus. The oil from Cymbopogon citratus and Citrus hystrix had the highest activity against S. typhi (60 and 21.67 mm, respectively), E. coli (60 and 20.33 mm, respectively), P. acnes (60 and 31.11 mm, respectively) and S. aureus (60 mm and 17.89 mm, respectively). The research results showed that the essential oils in this study had the potency for development as a natural antibacterial and antioxidants agents.
•We determined radical scavenging activity in seed and skin extracts and juice of V. opulus by on-line HPLC method.•Chlorogenic acid is the main compound identified with LC–MS in juice of V. ...opulus.•ABTS radical scavenging method has better characteristics over DPPH method in on-line HPLC applications.•The extractions with different solvents help elucidate different compounds of differing polarities.•The antioxidant activities of the seed extracts were higher than the skin extracts in V. opulus.
Antioxidant activity of the juice and seed and skin extracts prepared with methanol, acetonitrile, and water of Viburnum opulus L. grown in Eastern Black Sea Region were studied with an on-line HPLC–ABTS method and off-line antioxidant methods, among which a linear positive correlation was observed. The fruit extracts were analysed with the HPLC–UV method optimised with 14 standard phenolics. Identification of the phenolic components in the juice was made using an HPLC–UV–ESI-MS method. Nineteen phenolic compounds in juice were identified by comparing the retention times and mass spectra with those of the standards and the phenolics reported in the literature. The major peaks in the juice belonged to coumaroyl-quinic acid, chlorogenic acid, procyanidin B2, and procyanidin trimer. Quite different antioxidant composition profiles were obtained from the extracts with the solvents of different polarities. The antioxidant activities of the seed extracts were higher than those of the skin extracts in general.
Green tea is currently an area of intense scientific research because of its exceptional and effective actions in anticancer therapy. The aim of this research was to determine the antioxidant ...properties of polyphenols contained in green tea. Examined was the correlation between bioingredients of the product tested and the ability to scavenge free radicals and reduce them by chelating the variable metal ion. A range of innovative research technology combines HPLC with electrochemical (cyclic and differential pulse voltammetry) and spectrophotometric (ABTS, FRAP and DPPH assays) analysis to rate the potential oxidation-reduction components of green tea. Described is the dependence of the chemical structure on antioxidant properties. It was found that a high content of catechins and esters of the gallic-type had a powerful influence on the antiradical properties of the studied tea extract.
► DPPH assay is a common antioxidant assay. ► Variations in antiradical properties using DPPH Assay observed in literature. ► Examples highlighted with case studies along with our findings and ...remedies suggested.
Applications of antioxidants are increasing due to their multiple roles in minimising harmful effects of oxidative stress. 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay is routinely practiced for the assessment of antiradical properties of different compounds. A detailed literature survey revealed use of different materials and methods for DPPH assay by different investigators resulted in variation in the values of reference standards and measured parameters of new antioxidants. In the present work a detailed kinetic study of antioxidants has been performed and comprehensive results in terms of effective concentration which scavenges 50% radical (EC50), antioxidant reducing power (ARP), stoichiometry and second order rate constant (k2) values have been reported with DPPH assay. Importance of selection of appropriate reference compounds and kinetic calculations are suggested. Few case studies of standard antioxidants have been discussed to emphasise the utilisation of appropriate methodology and reference compounds.
•Fabrication of a Novel Nanocomposite (TiO2/WO3/V2O5) by Hydrothermal Method.•The degradation of methylene blue, methyl orange and orthonitrophenol was up to 76%, 86% and 86% respectively.•A ...hydrothermal Approach towards waste water treatment, an innovative roadmap to green chemistry.
The catalytic removal of orthonitrophenol (O-NP), methylene blue (MB), and methyl orange (MO) was investigated to determine the photo-catalytic reactivity. The WO3/TiO2/V2O5 catalyst was successfully fabricated by hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Ultra violet visible spectroscopy (UV–visible) and Fourier transform infrared spectroscopy (FTIR) to determine structure, morphology and functional groups. The photocatalytic potential of the synthesized nanomaterial was tested for the degradation of pollutants. The results indicated that the degradation of methylene blue, methyl orange and orthonitrophenol was up to 76%, 86% and 86% respectively. Moreover, radical scavenging potential of the nanocomposite was evaluated by employing 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 2,2′-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid (ABTS•+) assays thus, indicating excellent photocatalytic potential. The present study developed a new strategy to prepare the recoverable TiO2/WO3/V2O5 nanocomposite for the degradation of hazardous pollutants.
Vegetables have reported to contain high content of wide verity of important phytochemicals that can be used in medical approach. Bell pepper are one of the most important vegetables that can be used ...as spice in foods, as well as it has a diversity of the phytochemical compounds. Carotenoids, vitamin A, vitamin C, polyphenolic compounds and other metabolites were found in bell peppers of all colors. Red pepper is characterized by its high content of β-carotene. Our goal was to prepare an aqueous red pepper extract solution and use it to synthesize Ag NPs, then examine the antioxidant activity of the extract and the nanoparticle solutions. Ag NPs were prepared at room temperature by utilizing the aqueous red pepper extract solution as well as characterized by using UV-Vis spectrophotometry and field emission scanning electron microscope. The characterization result has shown the presence of Ag NPs in particle average of approximately 58 nm. The antioxidant activity was determined by using a DPPH assay, where ascorbic acid has shown IC50 of 23.71 μg/mL which was lower than Ag NPs (IC50 = 43.72 μg/mL). The best antioxidant behavior was obtained from the red pepper extract solution (IC50 = 17.26 μg/mL). This may attributed to the high content of phytochemicals in the extract solution. Importantly, the use of red pepper extract solution in preparing AgNPs have shown to improve their antioxidant activity, which is considered as good additive to the medical features of Ag NPs.
In this study, the isolation and identification of Exopolysaccharide (EPS) producing bacteria from polluted soil samples and its in vitro antioxidant activities were investigated.
Isolation and ...identification of bacteria was investigating using 16 s rDNA genome sequencing method. Further, optimization (pH, time, and temperature), purification and characterization of EPS were performed using different (UV, FT-IR, C13-NMR and H1-NMR) methods. In addition, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide (H2O2) scavenging activities of EPS were performed.
The molecular characterization of isolated strain was confirmed as Bacillus aerophilus by 16S rDNA sequencing. The sequence was submitted to NCBI (Genbank accession number MH553072). Characterization of EPS by UV, FT-IR, C13-NMR and H1-NMR revealed the presence of hydroxyl, carbonyl, and carboxyl functional groups. SEM analysis of EPS showed a solid surface with an irregular shape. The optimum conditions for EPS production were pH 7.0, cultivation time 72 h (3.73 ± 0.211 g/L) and temperature 30 °C respectively. The yeast and sucrose extract showed higher EPS production. In addition, in vitro DPPH, H2O2 studies showed 56.6 and 67.5% of scavenging activity at 4 mg/mL of concentration.
From this study, the novel EPS producing Bacillus aerophilus rk1 was identified. Further, the purified EPS showed good antioxidant activity.
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