Ferric Reducing Ability Of Plasma Assay Research Articles

Comparison of antioxidant levels and anti-inflammatory activities of kelulut honey harvested at different month of intervals and its chemical compositions

Background: Harvesting time might influence the biological activities of honey, which is crucial for honey quality. Objectives: This study aims to evaluate the optimum time for harvesting kelulut honey (KH) by determining its antioxidant and anti-inflammatory activities and chemical composition at different harvesting times. Materials and Methods: KH harvested at three different intervals (1, 2, and 3 months) was supplied by Rimbunan Hijau Bee Farm, located in Sarawak, Malaysia. The total phenolic content (TPC) and antioxidant level of KH were determined using Folin–Ciocalteu reagent and 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), and ferric-reducing ability of plasma assays, respectively. The cytotoxicity and anti-inflammatory effects of KH were evaluated on murine macrophage cells (RAW 264.7) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lipopolysaccharide (LPS)-induced nitric oxide (NO) production. The chemical composition of KH was analyzed by gas chromatography-mass spectrometry (GC-MS). Results: TPC and antioxidant levels of KH collected at different intervals showed no statistically significant difference (P > 0.05). KH at 1% concentration showed no cytotoxic activity toward RAW 264.7 cells after 24 h incubation. However, 1% KH showed no inhibition on NO production in LPS-induced RAW cells compared to the control. GC-MS revealed that hydroxymethylfurfural was present with the highest concentration in all samples. Conclusion: This study suggests that harvesting time does not influence the biological activities of KH.

Combined Multi-assay Evaluation of the Antioxidant Properties of Tree Bark

Abstract Wood logging generates considerable amounts of bark by-product, which are a potential antioxidant source well worth extracting and using. The present work compares the antioxidant properties of the bark of the following selected Hungarian forest tree species: white poplar (Populus alba L.), black locust (Robinia pseudoacacia L.), sessile oak (Quercus petraea Liebl.), black poplar (Populus nigra L.), silver birch (Betula pendula Roth), European larch (Larix decidua Mill.), scots pine (Pinus sylvestris L.), wild cherry (Prunus avium L.), European hornbeam (Carpinus betulus L.) and sweet chestnut (Castanea sativa Mill.). Inner and outer bark were investigated separately. Total polyphenol content (TPC) was determined by the Folin-Ciocâlteu method, whereas antioxidant capacity was assayed using the ferric reducing ability of plasma (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH), and ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) methods. The overall antioxidant power of the samples was evaluated using a scoring system that combined the FRAP, DPPH, and ABTS assay results. The TPC levels did not always follow the FRAP, DPPH, and ABTS assay values. Differing reaction mechanisms and sample compositions are possible reasons for this. The presented scoring evaluation was suitable for the assessment and comparison of complex antioxidant properties of tree bark samples. According to the scores, inner bark showed higher scores compared to outer bark for most species with the exceptions of black poplar, black locust, white poplar, sweet chestnut, and European larch. The highest overall antioxidant capacities were determined in the inner bark of wild cherry and the outer bark of sweet chestnut. The species with the overall lowest scores were black locust and black poplar.

Radiation-inducible radioprotective exopolysaccharides of Bacillus siamensis CV5 from irradiated roots of Cistanche violacea to decrease free radical damage produced by ionizing radiation

Purpose: To assess exopolysaccharides (EPS) of Bacillus siamensis CV5, isolated from irradiated roots of Cistanche violacea, for their induction by ionizing radiation (IR) and their antioxidant and radioprotective power.Materials and methods: Isolated bacteria from the roots of C. violacea were screened for EPS production. The most EPS-producing bacterium was selected and the response surface methodology (RSM) was applied to elucidate the IR dose effects on EPS production. Gamma irradiation effects on the morphology and functional groups of EPS were studied using microscopy and Fourier transform infra-red (FT-IR). The radioprotective potential of EPS on the survival of B. siamensis CV5 following IR was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Free radicals scavenging potentialities (FRSP) of non-irradiated and irradiated EPS were evaluated through 2, 2−-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and ferric reducing ability of plasma (FRAP) assays.Results: Twenty strains, isolated from irradiated roots of C. violacea, were screened for their EPS production. IR-resistant B. siamensis CV5 was the most EPS-producing strain. Its purified EPS contained rhamnose, fructose, mannose and glucose. RSM indicated that EPS of CV5 (CV5-EPS) are radiation inducible. Micrographs of CV5-EPS suggested an increase in the total area and a decrease in the Feret’s statistical diameter following exposure to IR. FT-IR spectra of these EPS revealed an increase of various functional groups. The MTT survival assay demonstrated a positive correlation between the added quantity of CV5-EPS and the viability of irradiated CV5 (p < .01). DPPH, ABTS and FRAP assays indicated that the antioxidant activities of CV5-EPS increased significantly with the irradiation dose (p < .01).Conclusions: CV5-EPS were demonstrated as radiation-inducible and radioprotective biomolecules. This radioprotective potential of CV5-EPS could be associated with their antioxidant activities. In the future, irradiated EPS could be tested as a gel in cancer radiotherapy for minimizing the damage caused by rays to surrounding healthy tissues.

Effect of pesticide exposure on total antioxidant capacity and biochemical parameters in Brazilian soybean farmers

Farmers represent a population highly vulnerable to the toxic effects of pesticide exposure. Antioxidant capacity and biochemical parameters have been used as biomarkers of occupational exposure to pesticides. The aim of this study was to evaluate hepatic and renal parameters as well as butyrylcholinesterase (BChE) activity and ferric-reducing ability of plasma (FRAP) considering high and low exposure periods in soybean farmers in southern Brazil. The exposed group consisted of 50 soybean farmers. Two control groups were used, composed by 35 (Novo Hamburgo control group) and 28 (Sertão control group) subjects not exposed to pesticides. Farmers blood samples were collected during the high and low pesticide exposure periods. BChE, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), urea, and creatinine levels were determined. The FRAP assay was carried out to evaluate the antioxidant potential in the exposed group. Considering the exposed group, significantly lower BChE and increased AST activity were observed during high pesticide exposure period as well as higher FRAP, urea and creatinine levels; however, ALT and GGT did not differ between the two periods. When compared with the control groups, only urea and creatinine were higher in the exposed group. The present results indicate that occupational exposure to mixtures of pesticides might elicit adverse effects at the biochemical level. In addition, the study highlights the importance in considering periods of a same crop season with different degree of pesticide exposure during biologic monitoring of these biochemical parameters.

Evaluation and comparison of in vitro antioxidant activities of unsaponifiable fraction of 11 kinds of edible vegetable oils.

The radical scavenging capabilities of the extracts from eleven edible vegetable oils were investigated by using 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), 2,2′‐azino‐bis‐3‐ ethylbenzothiazoline‐6‐sulfonic acid (ABTS), and ferric reducing ability of plasma (FRAP) assays. The results indicated that rapeseed oil and sesame oil showed higher radical scavenging abilities than other vegetable oils. When the radical scavenging capabilities of the extracts from virgin camellia oils and commercially available refined camellia oils were evaluated by FRAP assay, the results showed that the antioxidant capabilities of the former were higher than the latter. Therefore, it is recommended that moderate refining processes should be taken to minimize the loss of antioxidant components and people consume virgin oils or less processed edible vegetable oils for higher antioxidant activities.

Exercise and Tart Cherry Increase Antioxidant Capacity after High‐Fat Meal Consumption

BackgroundExercise and high phytonutrient foods have the potential to combat negative effects associated with a high‐fat (HF) meal by lowering postprandial oxidative stress and increasing antioxidant capacity.MethodsThirteen normal weight men (18–30 y), participated in a randomized cross‐over design of four trials: 1) HF meal plus Montmorency tart cherry (C), 2) HF meal plus placebo (P), 3) prior exercise to a HF meal plus Montmorency tart cherry (EC), and 4) prior exercise to a HF meal plus placebo (EP). For exercise trials, a 30 min bout of submaximal treadmill running was performed the afternoon prior to the HF test meal. The HF meal contained 920 kcals and 60 g of fat, with the total percent of calories coming from fat being 59%. Antioxidant capacity of plasma was measured at fasting, and 1, 2, and 3 hours postprandially.ResultsPostprandial oxygen radical absorbance capacity (ORAC) was significantly greater in the CE vs. PE trial (incremental area under the curve (iAUC): 4.10±1.59 vs. −0.58±1.70 mmol Trolox/L/3h, for CE vs. PE, respectively; p &lt; 0.05). There were no other ORAC or postprandial ferric reducing ability of plasma (FRAP) differences between trials.ConclusionThe CE trial resulted in greater postprandial antioxidant capacity compared to the PE trial as measured by ORAC. The lack of differences found using the FRAP assay indicates that Montmorency tart cherry consumption reduces oxidative stress primarily through a hydrogen atom transfer mechanism, as indicated through ORAC, rather than a single electron transfer as measured with FRAP.Support or Funding InformationResearch was supported by a seed grant from the AU/UGA Medical Partnership and UGA Clinical and Translational Research Unit.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Ferric reducing ability of plasma and assessment of selected plasma antioxidants in adults with celiac disease.

Oxidative stress with an excessive free radical production and a reduction in the activity of protective antioxidants is considered as one of the mechanisms responsible for gluten toxicity. However, its role in celiac disease (CD) is unclear. Evaluation of plasma nonenzymatic antioxidant capacity in patients with CD (both untreated patients and those receiving gluten-free diet [GFD]) by measuring the ferric reducing ability of plasma (FRAP) as well as assessing selected plasma antioxidants. The study included 169 adult patients: 48 patients with untreated active CD, 72 patients with CD on a GFD, and 49 healthy controls. In each group, we measured the serum levels of selected antioxidants (uric acid, bilirubin, albumin, and vitamin E) and used the FRAP assay to assess the total antioxidant capacity (TAC) of plasma. In each patient, serological and histopathological activity of CD was also evaluated. There were no significant differences in the TAC of plasma measured with the FRAP assay between the study groups. Patients with CD had higher uric acid levels compared with controls (p <0.001), while bilirubin levels were lower in patients with active disease than in controls (p <0.05). Serum vitamin E levels were lower in all patients with CD compared with controls (p <0.01). The FRAP assay is not the method of choice for assessing the TAC of plasma in patients with CD. Owing to high serum uric acid levels, the FRAP assay results in these patients may be overestimated despite the reduced levels of other plasma antioxidants.

An evaluation of the antioxidant properties of iodinated radiographic contrast media: An in vitro study.

This study reveals the antioxidant properties of iodinated radiographic contrast media to be used in diagnostic radiology. Di(phenyl)-(2,4,6-trinitrophenyl) iminoazanium (DPPH), ferric reducing ability of plasma (FRAP), and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) assays were used for determining in vitro the antioxidant properties of five iodinated radiographic contrast media such as iobitridol (xenetix), iodixanol (visipaque), iohexol (omnipaque), ioxaglate (hexabrix), and isovue (iopamiro). An ascorbic acid and Trolox solution served as a positive control. The absorbance intensity of the colored product was recorded using a spectrophotometer. For DPPH and ABTS assay, the absorbance intensity at 533 and 752 nm, respectively was decreased when compared to control; it indicated an increase in antioxidant activity. For FRAP assay, the absorbance intensity at 593 nm was increased when compared to control; it indicated an increase in antioxidant activity. The results showed that five iodinated radiographic contrast media did not differ in DPPH• radical-scavenging activity when compared to a corresponding control. The ferric reducing ability of all of these iodinated radiographic contrast media also did not differ when compared to a corresponding control, except for iobitridol at 200 mgI/mL and ioxaglate at 50-200 mgI/mL. All iodinated radiographic contrast media showed ABTS•+ radical-scavenging activity. This finding suggested that iobitridol, iodixanol, iohexol, ioxaglate, and isovue exhibited weak in vitro antioxidant properties. The antioxidant ability depended on the type of free radical production and the concentration of iodinated radiographic contrast media.

Plant growth-promoting bacteria elevate the nutritional and functional properties of black cumin and flaxseed fixed oil.

In order to study the influence of plant growth-promoting bacteria (PGPB) belonging to Streptomyces sp., Paenibacillus sp., and Hymenobacter sp. on fixed oil content of flaxseed and black cumin, 2-year field experiments were conducted. PGPB was applied during seedtime of plants. The extraction of oil from seeds was performed using supercritical CO2 . The addition of PGPB significantly increases the content of C18:1 (from 16.06 ± 0.03% to 16.97 ± 0.03%) and C18:3 (from 42.97 ± 0.2% to 45.42 ± 0.5%) in flaxseed oil and C18:2 (from 52.68 ± 0.50% to 57.11 ± 0.40%) and C20:2 (from 4.34 ± 0.02% to 4.54 ± 0.03%) in black cumin seed oil. The contents of total polyphenols, flavonoids, and carotenoids, as well as antioxidant activity measured by ferric-reducing ability of plasma assay, were found to be greater in the oil from the seeds of plants treated with the PGPB, compared with the respective non-treated samples. The use of PGPB enhances plant nutritive properties; these represent a great source for obtaining valuable functional food ingredients. © 2017 Society of Chemical Industry.

IN VITRO ANTIOXIDANT ACTIVITY OF BARK EXTRACTS OF OROXYLUM INDICUM (L) VENT

Objectives: The aim of the present work is to screen the antioxidant potentiality of the bark extract of Oroxylum indicum (L) Vent, ethnomedicinally prescribed plant as hepatoprotective.Methods: Bark extracts were prepared using soxhlet apparatus. Total phenol, flavonoid, and total alkaloid were analyzed using Folin–Ciocalteu assay, aluminum chloride colorimetric assay, atropine standard, respectively. Antioxidant capacity and free radical scavenging potentialities were done by several in vitro methods, viz.; 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide scavenging activity, reducing power assay, metal chelating activity, ferric reducing ability of plasma (FRAP) assay, and thiobarbituric acid (TBA) method.Result: Total phenol, flavonoid, and alkaloid were found to be highest in methanolic extract of O. indicum (L) Vent. Methanolic extract of the bark showed very low inhibitory concentration (IC50) and effective concentration values for DPPH assay and reducing power assay compared to another extract. In hydrogen peroxide scavenging activity assay, the lowest IC50 value was recorded in methanolic extract with 153.45±0.06 μg/ml. The FRAP assay for O. indicum methanolic extract showed the highest activity at 940.09±0.07 μg/mL of ascorbic acid equivalent. The ferric reducing capacity and TBA values of the plant extracts confirmed the presence antioxidant principles in the bark of the said plant.Conclusion: These underused plants may be used for mitigating the detrimental effect of oxidative stress and reactive oxygen species-mediated disease and thus justifies its use in folklore medicines.

Antioxidant efficiency of Beech (Fagus sylvatica L.) bark polyphenols assessed by chemometric methods

Beech (Fagus sylvatica L.) is a common industrial wood species. Its bark is mostly regarded as a by-product, however it is an abundant source of antioxidant polyphenols worthwile to extract and to utilize for various purposes. Hitherto, it has been unknown which polyphenols are primarily responsible for the antioxidant properties. The objective of the present study was to implement chemometric methods for the identification of the compounds which are mostly responsible for antioxidant effects. With this knowledge extraction can be optimized, antioxidant properties can be enhanced. Earlier published data on the polyphenolic composition and antioxidant properties of altogether 26 extract solutions were evaluated in the present study. Antioxidant capacity of the extracts was determined with DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) and FRAP (ferric reducing ability of plasma) assays. Relative concentrations of polyphenols were measured with high-performance liquid chromatography/tandem mass spectrometry by means of MRM (multiple reaction monitoring) peak areas. Chemometric methods involved correlation analysis, factor analysis and cluster analysis. A scoring system was applied for the evaluation of chemometric results. The five overall most efficient antioxidants in beech bark were found to be (+)-Catechin>Procyanidin B dimer 2> Unidentified 5>(−)-Epicatechin>Coniferin isomer 2 compounds. Isomers of Procyanidin B dimers and C trimers were shown to have different antioxidant efficiency. Significant DPPH prooxidant effects of Coniferin isomer 1 and Syringic acid-di-O-hexoside 1 were reported. The presented evaluation could be used for the assessment of the antioxidant efficiency of compounds in other plant extracts, too.

Electroanalysis and laccase-based biosensor on the determination of phenolic content and antioxidant power of honey samples

Honey is a functional food widely consumed. Thus, the evaluation of honey samples to determine its phenolic content and antioxidant capacity (AOC) is relevant to determine its quality. Usually AOC is performed by spectrophotometric methods, which lacks reproducibility and practicality. In this context, the electroanalytical methods offer higher simplicity and accuracy. Hence, the aim of this work was to use of electroanalytical tools and laccase based biosensor on the evaluation of AOC and total phenol content (TPC) of honey samples from different countries. The antioxidant power established by electrochemical index presented good correlation with the spectrophotometric FRAP (Ferric Reducing Ability of Plasma) and DPPH (2,2-Diphenyl-1-Picrylhydrazyl) radical scavenging assays. Also, TPC results obtained by the biosensor agreed with the Folin-Ciocalteu (FC) assay. In addition to the semi quantitative results, the electroanalysis offered qualitative parameters, which were useful to indicate the nature of major phenolic compounds.

Safety evaluation of an oat grain alkaloid gramine by genotoxicity assays

Gramine is a natural indole alkaloid that has been isolated from different raw plants occurring mainly in Avena sativa, etc. The study was aimed to investigate the possible in vitro antioxidant, in vitro mutagenic, in vitro antimutagenic, and in vivo genotoxic activity of gramine using ferric reducing ability of plasma (FRAP) assay, Metal chelating, Ames bacterial reverse mutation test, and the mouse bone marrow micronucleus assay as well as chromosomal aberration. Four concentrations of gramine viz. 250, 500, 1000, and 2000 μg/mL were evaluated for its antioxidant activity in FRAP Assay and Metal Chelating Test. Four concentrations of gramine (1250 μg/plate, 2500 μg/plate, 5000 μg/plate, and 10 000 μg/plate) were employed in Salmonella typhimurium strains to study the mutagenicity in the presence and absence of standard mutagens, 2-aminofluorene (2-AF), sodium azide (SA), and 2-nitrofluorene (2-NF). Three doses, i.e. 0.1, 0.2, and 0.3 × the LD50 of gramine (i.e. 50 mg/kg, 100 mg/kg, and 150 mg/kg) were administered orally to either sex of Swiss albino mice for 48 h to study the genotoxic activity in micronucleus assay as well as chromosomal aberration. Gramine showed potent antioxidant activity in both the assay. Gramine at the given dose lacks mutagenicity as well as found to possess antimutagenic efficacy. Interestingly, S9 enzymes increase the antimutagenic activity in a dose-dependent manner. There was no significant increase in the frequency of micronucleated polychromatic erythrocytes (MNPCEs), as well as no significant difference in the percentage of chromosomal aberrations was observed between the gramine groups and the negative groups but percentage of polychromatic erythrocytes (PCEs) is found to be higher in all the gramine groups. These results indicate significant antioxidant, non-mutagenic as well as non-genotoxic activity of gramine in vitro and in vivo in the given doses.

Analytical validation of an automated assay for ferric-reducing ability of plasma in dog serum.

We performed analytical validation of an automated ferric-reducing ability of plasma (FRAP) assay in the serum of dogs. Intra- and interassay precision, accuracy, detection limit, and effects of hemolysis and lipemia were evaluated. Intra- and interassay coefficients of variation were <1% and <13%, respectively. The assay showed a high correlation with a FRAP assay described previously, and results were linear when serial sample dilutions were tested. The detection limit was lower than the values observed in sera from healthy dogs; decreased serum FRAP was found in dogs with leishmaniosis. Lipemia and hemolysis caused a significant increase in the results of the assay.

Evaluation of antioxidant and anticancer activities of chemical constituents of the Saururus chinensis root extracts.

Evaluation of antioxidant and anticancer activities were screened by various Saururus chinensis root extracts. Four solvents (ethyl acetate, methanol, ethanol, and water) extracts were investigated for their total flavonoids, phenol contents and their antioxidant activity of DPPH (2,2-diphenyl-1-picrylhydrazyl), NO (nitric oxide), H2O2 (hydrogen peroxide), ABTS 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonicacid)diammonium assays, FRAP (ferric reducing ability of plasma) assays and anticancer activity. The total phenolic and flavonoid content of extracts were determined by using FC (Folin–Ciocalteu) and AlCl3 colorimetric assay method. Total flavonoid content in these plants ranged from 24.7 to 72.1 mg g−1 and amount of free phenolic compounds was between 11.2 and 67.1 mg g−1 extract. The all extracts have significant levels of phenolics and flavonoids content. Anticancer activity was screened for MCF-7 breast cancer cell line. Ethanol extract shows significant of antioxidant activity and water extract shows significant of anticancer activity compared with standard (BHT) butylated hydroxy toluene. These ethanol and water extracts could be considered as a natural source for using antioxidant, and anticancer agents compared to commercial available synthetic drugs.

Phytochemical Study of Aegle marmelos: Chromatographic Elucidation of Polyphenolics and Assessment of Antioxidant and Cytotoxic Potential.

Background:The antioxidant potential of medicinal plants has been illustrated through many reports clearly depicting that plants are a rich source of antioxidants, making them a great resource of novel drugs and health-care products.Objectives:The current study is, therefore, focused toward the assessment of antioxidant properties along with the presence of phytochemicals in leaves of 18 varieties/accessions of Aegle marmelos.Materials and Methods:The antioxidant activities were initially measured using superoxide radical scavenging method, 2, 2-diphenyl-1-picrylhydrazyl (DPPH), and ferric-reducing ability of plasma assays. Further, thin-layer chromatography (TLC), high-performance TLC, and column chromatography were performed to isolate the potentially active fraction and anti-inflammatory activity of crude, and the isolated fraction was tested on J774 macrophage cell line.Results:The maximum inhibition of superoxide anions was shown by Pant Aparna. Additionally, Pant Aparna extract was most efficient, exhibiting 92.0% inhibition in scavenging the DPPH radicals. The content of total carotenoids was found to be higher in Pant Aparna among all the varieties/accessions. Furthermore, the crude extract and the fraction A. marmelos methanolic fraction 21 (AMMF21) were found to be nontoxic and significant reactive oxygen species, and NO inhibition was observed in a concentration-dependent manner. Moreover, the methanolic extract of variety Pant Aparna showed promising in vitro antioxidant activity, indicating its potency for therapeutic applications.Conclusion:In brief, this is the first ever report on Pant Aparna as the best variety in terms of phytocompounds and identification of potential antioxidant activity. In addition, the AMMF21 fraction of methanolic extract possessing best antioxidant activity on macrophage cells indicates its use as a novel phytotherapeutic agent.SUMMARY Our study identifies the best variety/accession of Aegle marmelos possessing the potential antioxidant and reactive oxygen species scavenging activity possessed by the methanolic crude extract of variety Pant Aparna along with the fraction A. marmelos methanolic fraction 21 isolated through column chromatography on J774 murine macrophage cell lineThe high-performance thin-layer chromatography fingerprinting profile obtained acts as a diagnostic tool to identify and determine the quality and purity of this extract and fraction in future studiesOn the basis of the results obtained, the above variety should be taken further to exploit its immense potential for other biological activities of medicinal importancePant Aparna is an outstanding variety of A. marmelos and should be extensively studied for isolation of a novel and potential therapeutic agent. Abbreviations used: AMMF21: Aegle marmelos methanolic fraction 21, DPPH: (2, 2-diphenyl-1-picrylhydrazyl), FRAP: Ferric-reducing ability of plasma, HP-TLC: High-performance-thin-layer chromatography, TLC: Thin-layer chromatography, TCA: Trichloroacetic acid, TPTZ: 2,4,6-Tripyridyl-s-triazine, DNPH: 2,4-dinitrophenyl hydrazine, NBT: Nitroblue tetrazolium, NADH: Nicotinamide adenine dinucleotide, PMS: Phenazine metho-sulfate, DMEM: Dulbecco's modified Eagle medium; MTT: (3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide, DCFDA: 2’,7’-dichlorofluorescein diacetate, LPS: Lipopolysaccharide, NED: N-(1-Naphthyl) ethylenediamine.

COMPARATIVE STUDY OF ANTIOXIDANT ACTIVITIES, COSMECEUTICAL PROPERTIES AND PHENOLIC ACIDS COMPOSITION OF FERMENTED RICE BRAN AND COCONUT TESTA

Malaysia produces large number of agro-industrial products annually including rice and coconut. Along with the production, rice bran and coconut testa are also abundantly generated as by-products. Solid state fermentation (SSF) is a simple biotechnological technique that has been employed for production of bioactive compounds. The use of SSF on agro-industrial by-products is economically viable and helps to reduce the environmental impact of the by-products disposal. In this present study, rice bran (RB), coconut testa (CT) and a combination of rice bran and coconut testa (RBCT) were fermented with single culture of Aspergillus oryzae and Rhizopus oligosporus. The effect of fungal SSF on the cosmeceutical-related activities and phenolic acid content of the fermented RB, CT and RBCT extracts was determined. The results showed that total phenolic content (TPC) as well as antioxidant activity measured using the ferric reducing ability of plasma (FRAP) of all substrates increased upon fermentation. Contrary to the TPC and FRAP assays results, the radical-scavenging activity of the fermented samples as measured by using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, were varied. Tyrosinase inhibition activity was found to be the highest in the extract of RB fermented with A. oryzae (56.18%) compared to other extracts. The same extract showed the highest elastase inhibition activity with a value of 60.27%. High performance liquid chromatography (HPLC) analyses showed ferulic, sinapic, caffeic and protocatechuic acids were significantly increased in RB fermented with A. oryzae. The results of this study suggest that fungal solid-state fermentation of rice bran may have the potential to be exploited in producing different types of active metabolites that are useful for cosmeceutical industries

Antioxidant potential of Juglans nigra, black walnut, husks extracted using supercritical carbon dioxide with an ethanol modifier.

The black walnut, Junglas nigra, is indigenous to eastern North America, and abscission of its fruit occurs around October. The fruit consists of a husk, a hard shell, and kernel. The husk is commonly discarded in processing, though it contains phenolic compounds that exhibit antioxidant and antimicrobial properties. For this study, black walnut husks were extracted using supercritical carbon dioxide with an ethanol modifier. The effects of temperature, ethanol concentration, and drying of walnut husks prior to extraction upon antioxidant potential were evaluated using a factorial design of experiments. The solvent density was held constant at 0.75 g/mL. The optimal extraction conditions were found to be 68°C and 20 wt‐% ethanol in supercritical carbon dioxide. At these conditions, the antioxidant potential as measured by the ferric reducing ability of plasma (FRAP) assay was 0.027 mmol trolox equivalent/g (mmol TE/g) for dried walnut husk and 0.054 mmol TE/g for walnut husks that were not dried. Antioxidant potential was also evaluated using the total phenolic content (TPC) and 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH) assays and the FRAP assay was found to linearly correlate to the TPC assay.

Antioxidant Activity in Pulp and Peel of Three Mango Varieties

The aim of the present study was to estimate the content of total polyphenols and flavonoids and to investigate in-vitro antioxidant potential of methanolic extracts of peel and pulp in three Indian mango varieties. Antioxidant activity was assessed using [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)] ABTS+ assay, 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay, ferric-reducing ability of plasma (FRAP) assay, and phosphomolybdate assay for Total Antioxidant Capacity (TAC). Total phenolic and flavonoid content was also determined, and expressed in gallic acid equivalent (GAE) and quercetin equivalent (QE), respectively. Results of this study indicated that methanolic extracts of mango peel had significantly higher antioxidant activity compared to that of pulp (29.69 and 3.12), irrespective of the method or variety used. Free radical scavenging and antioxidant activity may be attributed to presence of phenolic (24.61mg GAE/g DM in the peel and 2.01mg GAE/g DM in the pulp) and flavonoid compounds (24.95mg QE/g DM in the peel and 16.15mg E/g DM in the pulp). Antioxidant activity determined by ABTS, DPPH and FRAP assays in mango peel was significantly higher than in the mango pulp (24.95 1.96mg TE /g DM, 23.68 versus 4.60mg BHA/g DM and 40.52 versus 2.781mg TE/g DM), respectively. Results for scavenging activity against DPPH were 96.18% for the peel and 23.86% for the pulp, while, free radical scavenging activity results using ABTS+ assay were 99.62% in the peel and 13.46% in the pulp. Our study justifies research in processing of mango peel into useful, functional food ingredients (powders or extracts).

Evaluation of antioxidant activity and phenolic profile of filamentous terrestrial cyanobacterial strains isolated from forest ecosystem

The present study aims to investigate antioxidant activity and the phenolic content in five terrestrial cyanobacterial strains isolated from the Fruska Gora mountain forest ecosystem (Serbia). The antioxidant activity of crude ethanolic extracts was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing ability of plasma (FRAP) assay. All the tested cyanobacterial strains belonging to Phormidium, Nostoc, Oscillatoria, Anabaena, and Calothrix genera exhibited antioxidant activity. The ethanolic extracts from Calothrix M2 showed strong inhibition against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals (half maximal inhibitory concentration (IC50) = 30.72 ± 3.31 μg mL−1) whereby Phormidium M1 expressed the highest radical potential in FRAP assay (22.48 ± 2.18 mg ascorbic acid equivalents (AAE) g−1). Furthermore, the presence and content of 15 phenolics in ethanolic extracts of the tested cyanobacterial strains were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The richest strain in polyphenolics was Phormidium M1 which contained 12 compounds, mostly phenolic acids and flavonoid glycosides, followed by Nostoc M1 and Oscillatoria M2. The noticeable amount of phenolic acids (quinic acid 502 μg g−1; gallic acid 84.9 μg g−1; vanillic acid 50 μg g−1) was observed in Phormidium M1 indicating that phenolic compounds could contribute to the antioxidant activity observed in FRAP assay. LC-MS/MS analysis showed that the tested terrestrial cyanobacterial species could be regarded as a promising new source of bioactive phenolic compounds. Since no significant correlation was observed between phycocyanin content and antioxidant activity, other compounds present in the crude extracts contributed to antioxidant capacities in DPPH and FRAP assay. This study highlights the potential of terrestrial cyanobacterial strains inhabiting forest ecosystems as an interesting source of compounds with antioxidant potential for further researches and exploitation.