Radical Scavenging Activity Of Samples Research Articles

The simultaneous influence of ultraviolet rays and cold plasma on the physicochemical attributes and shelf life of dried pistachios during the storage period

AbstractThis investigation aimed to assess the simultaneous impact of ultraviolet (UV) and cold plasma (CP) on the quality and microbial attributes of dried pistachios during the storage period. Currently, novel nonthermal technologies exhibit high potential as a low‐cost, efficient, additive‐free, and nonpolluting strategies for fungi deactivation and mycotoxins degradation in foods. Over recent years, the combination of CP with other procedures, such as ultraviolet (UV) irradiation, ultrasound, ozone, and so forth, has been proposed and attracted lots of attention. For this purpose, in this study, the simultaneous effects of ultraviolet rays and cold plasma on dried pistachios artificially contaminated with aflatoxigenic fungi were assessed. The physicochemical attributes and surface morphology of pistachios were evaluated as well. The concentration of aflatoxin produced was investigated via high‐performance liquid chromatography. Artificially contaminated pistachios were treated with cold plasma at 80 W constant power level at both 10 and 15 min. Following the plasma treatment, pistachio samples were treated by ultraviolet rays at 354 nm wavelength and current intensity in 0.25 A at the same time. The results of this study revealed the fungal deactivation rate achieved by UV‐CP treatment was greater than the sum of the deactivation rates of distinct UV and CP treatments, as maximum reduction of Aspergillus oryzae count (3.7 CFU/g) observed after simultaneous UV‐CP treatment for 15 min (p < 0.05). Moreover, no substantial modifications were detected in the investigation of pH and DPPH radical scavenging activity of samples treated with UV‐CP (p > 0.05). The results of this study confirm the effectiveness of the simultaneous application of UV rays and CP in nuts to maintain quality and increase useful life, along with an alternative method for thermal treatments.Practical applicationsUsually, nonthermal procedures lead to their destruction by changing the chemical structure of mycotoxins. Ultraviolet (UV) radiation being a nonthermal technology, the benefits of its usage are various: the least loss of nutrients and sensorial quality of foods, no toxic residues, and low energy consumption compared with other thermal treatments normally applied for food decontamination. The latter is the main purpose of this technique due to its effectiveness in the inactivation of pathogenic microorganisms and spoilage. Besides this, Cold plasma (CP) technology has been displayed to overcome many of the insufficiency of regular decontamination strategies in the food industry, with slight damage to the quality of products and high efficiency. Although several physical procedures have shown acceptable results in the decontamination of fungi and degradation of mycotoxins in many foods, to date there are few published works on the effects of simultaneous application of UV radiation and CP on foods, particularly pistachios in is available. Hence, the intention of this investigation was to assess the effect of combination of UV radiation and CP on the physicochemical attributes and shelf life of dried pistachios during the storage period.

Effects of molokhia (Corchorus olitorius) powders obtained by different drying methods on some selected properties of erişte, Turkish noodle

Corchorus olitorius, known as molokhia, is a good source of protein, which makes it a cheap and high quality food material. Molokhia could be dried to obtain a new functional food ingredient. In this study, molokhia powders dried by different methods (oven, tray, microwave and vacuum drying) were used in erişte with 2.5, 5, 7.5 and 10% substitution ratios. Physical, chemical, sensory properties and cooking quality of erişte samples were investigated. Molokhia powder substitution led to an increase in the ash, crude fat and protein contents of erişte samples. Substitution ratio of 2.5% provided higher quality on the color, firmness and cooking quality properties. As the substitution ratio increased from 0% to 10%, the total polyphenolic content of erişte samples increased from 100.26 mg GAE/kg to 245.68 mg GAE/kg. Similarly, the DPPH radical scavenging activity of samples increased from 10.05% to 76.92%. Microwave drying has provided better color values and higher ash, crude fat and crude protein contents in erişte. Consequently, the nutritional properties of a traditional type of product, erişte was improved with molokhia powder substitution. Microwave drying was successfully applied to obtain high quality molokhia powders.

CuO/NiO bimetallic nanocomposite: A facile DNA assisted synthetic approach and evaluation of bio efficacy

In this present work, a simple chemical co-precipitation method was used to synthesize deoxyribonucleic acid (DNA) capped CuO-NiO bimetallic nanocomposite. The morphology and structure related properties of the samples were analyzed using Energy Dispersive X-Ray Analysis, X-Ray Diffraction, Transmission Electron Microscopy and Scanning Electron Microscopy. Widely used Agar well diffusion method evaluated the antimicrobial activity of the sample. DPPH and FRAP assays were applied to test the antioxidant activity of the sample. Average crystallite size of 16.218 nm NiO and 15.871 nm CuO were confirmed within CuO- NiO bimetallic oxide nanoparticles by means of XRD technique. EDAX studies confirmed the purity of the sample. The grain size obtained from TEM studies matches with the XRD results. The free radical scavenging activity of sample was higher in lower concentrations, viz. 0.1, 1, 5 and 10 µg/ml of the sample and activity decreased after that. The IC50 value in FRAP assay shows the potential of this mixed metal oxide nanoparticle in radical scavenging. In agar well cut method, the sample showed moderate antibacterial activity against Mycobacterium smegmatis and Salmonella typhimurium. The results also showed that the CuO-NiO bimetallic nanoparticles are biologically compatible, environmentally benign and economical material having potential applications in biomedical industry.

Antioxidant and Antiglycation Effects of Polyphenol Compounds Extracted from Hazelnut Skin on Advanced Glycation End-Products (AGEs) Formation.

The advanced glycation end-products (AGEs) arise from non-enzymatic reactions of sugar with protein side chains, some of which are oxido-reductive in nature. Enhanced production of AGEs plays an important role in the pathogenesis of diabetic complications as well as in natural aging, renal failure, oxidative stress, and chronic inflammation. The aim of this work is to study antiglycation effects of polyphenol compounds extracted by hazelnut skin that represents an example of polyphenols-rich food industry by-product, on AGEs formation. AGEs derived from incubation of bovine serum albumin (BSA) and methylglyoxal (MGO) were characterized by fluorescence. The phenolics identification and total polyphenol content in hazelnut skin extracts were analyzed by HPLC-MS and the Folin–Ciocalteu method, respectively. Antioxidant efficacy was evaluated by monitoring total antioxidant activity to assess the ABTS radical scavenging activity of samples by TEAC assay and oxygen radical absorbance capacity (ORAC) assay, expressed as millimoles of Trolox equivalents per gram of sample. Data here presented suggest that phenolic compounds in hazelnut skin have an inhibitory effect on the BSA-AGEs model in vitro, and this effect is concentration-dependent. The putative role of the hazelnut skin antioxidative properties for hindering AGEs formation is also discussed. Because of AGEs contribution to the pathogenesis of several chronic diseases, foods enriched, or supplements containing natural bioactive molecules able to inhibit their production could be an interesting new strategy for supporting therapeutic approaches with a positive effect on human health.

Assessment of flavonoids and phenolic compound accumulation in invasive Solidago canadensis L. in Slovakia

Solidago canadensis L. was introduced to Europe as an ornamental plant from North America in 1645 and began to spread during the XIX-XX centuries. Nowadays the species is considered the most aggressive invasive species. On the other hand, S. canadensis is considered to be a medicinal plant. The raw material known as Herba Solidaginis includes herbs of S. canadensis, S. gigantea, and S. virgaurea. These species are known for their diuretic, anti-inflammatory, antimicrobial, antioxidant, antispasmodic properties. The purpose of our study was to analyze the chemical compounds and some biological properties of S. canadensis, growing in Slovakia, to evaluate its therapeutic potential. The total phenolic content (TPC) of the extracts from aerial parts of S. canadensis was determined by the Folin-Ciocalteu method. The evaluation of total flavonoid content (TFC) was performed by using a spectrophotometric method. The flavonoids content was expressed as rutin equivalents (mg REs) per g DW vegetal product. The phytochemical profile of S. canadensis extracts was assessed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The radical scavenging activity of samples was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Reducing power of extracts was determined by the phosphomolybdenum method. Total phenolic contents (TPC) and total flavonoid contents (TFC) of the extracts varied from 204.19 to 293.43 mg GAE.g-1 DW, and 64.99 – 175.25 g QE.g-1 DW, respectively; the best results were obtained for ethanol extract. Some phenolic compounds were identified by HPLC with significant amounts of rutin (211.20 µg.mL-1), quercetin (122.08 µg.mL-1), quercitrin (102.50 µg.mL-1) and chlorogenic acid (147.00 µg.mL-1). The DPPH values in the inflorescences were higher than in the leaves: the antioxidant activity of leaf extracts was in the range from 5.34 to 17.16 mg TE.g-1, for inflorescences, this parameter ranged from 6.09 to 19.87 mg TE.g-1. The high total phenolic compounds and flavonoids can be used as a valuable source of phytochemicals in herbal remedies. Our study of S. canadensis, growing in Slovakia, shows the promising potential that can be evaluated as an effective antioxidant and antimicrobial agent in herbal medicines.

ANTIOXIDANT ACTIVITY AND PHENOLIC CONTENTS OF EXTRACTS FROM THE LEAVES OF ACANTHOPANAX TRIFOLIATUS HARVESTED IN DIFFERENT SEASONS

Acanthopanax trifoliatus or ‘Phak Paem’ is a deciduous shrub in Araliaceae which is commonly found in the north region of Thailand. This plant was traditionally used in Southeast Asia for ginseng-like purposes as a tonic to improve general weakness and for treatments of tuberculosis, lung hemorrhages and ulcers. Young leaves and the shoots are also popularly consumed as vegetables in northern Thai traditional cuisines. Leaf extracts of phak-paem were reported to promote some interesting biological effects including antioxidant, anti-inflammatory and anti-anxiety activities. This study aimed to evaluate the antioxidant properties of leaf extracts of A. trifoliatus collected from different seasons and quantitatively analyzed for both total phenolic and flavonoid contents. Eleven decoction extracts from the leaves of A. trifoliatus collected from different durations of a year were tested for free radical scavenging activity using DPPH scavenging assay and inhibition of lipid peroxidation of rat brain homogenate using TBARS method. Free radical scavenging activities of samples were evident while inhibitory effects to lipid peroxidation were evident too. Total phenolic and flavonoid contents of the extracts were determined using colorimetric methods. It was found that climatic condition such as temperature and rainfall had no effect to overall antioxidant activity of plant samples. However, samples collected in the winter especially in January and November were detected in high amount of total phenolic and flavonoid. This data suggests the optimum period for harvesting of plant raw material.

Phenolic composition and radical scavenging activity of commercial Greek white wines from Vitis vinifera L. cv. Malagousia

Seven commercial white wine samples of the Malagousia cultivar were investigated for the first time with regard to their phenolic composition and radical scavenging activity. Total phenol content, corrected for ascorbic acid contribution (0–47mg gallic acid equivalents/L of wine), ranged between 241 and 336mg gallic acid equivalents/L of wine. On the other hand, the range for total hydroxycinnamates was 51.5–122.4mg chlorogenic acid equivalents/L of wine and that for total flavanols 19.6–68.8mg catechin equivalents/L wine. Fifteen phenolic compounds were identified and quantified by gas chromatography/mass spectrometry in the selective ion monitoring and high-performance liquid chromatography coupled with diode array detector. Tyrosol, caftaric, caffeic and 2-S-glutathionyl caffeoyl tartaric (GRP) acids were the major phenolics in all samples with mean concentrations of 12.32, 10.71, 10.17 and 4.79mg/L wine, respectively. Catechin (3.75mg/L) and p-coumaric acid (3.04mg/L) followed in abundance. Variations in the values of GRP/caftaric (0.1–4.6) and caffeic/caftaric (0.4–4.2) acid concentrations, suggested differences in the degree of oxidation on one hand and hydrolytic processes during production and bottling on the other. Despite these variations, the radical scavenging activity of samples examined with DPPH and ABTS+ assays (mean value 0.85 and 3.45mmol Trolox equivalents/L of wine) indicated a high efficiency in comparison to literature data on native and foreign white wines. The present findings can be useful for both technological and nutritional purposes.

Antioxidant properties of some selected Indian medicinal plants: Their correlation with total phenolic contents

Background: Antioxidants play a major role in protecting the biological systems against oxidative stress, which is associated with development of many chronic diseases and disorders. Plants are the main sources of natural antioxidants in the form of phenolic compounds, which help human beings to deal with oxidative stress, caused by free radical damage. Aim: The present study aimed at the evaluation of antioxidant properties of extracts of different medicinal plants and their correlation with the total phenolic contents (TPCs). Materials and Methods: The selected plant materials were sequentially extracted with solvents with increasing polarity and analysed for their phytochemical constituents and antioxidant properties. The free radical scavenging activity of solvent extracts was assessed by 2,2‑diphenyl‑1‑picrylhydrazyl assay and TPCs by Folin‑Ciocalteu method. Results and Conclusions: In preliminary assay, 35 plants were screened for antioxidant properties, among them four plants were selected for the study. The methanol extracts of Acacia catechu (AC‑ME), Adenanthera pavonia (AP‑ME), Holopetelea integrifolia (HI‑ME) and ethanol extract of Terminalia paniculata (TP‑EE) showed highest antioxidant activity with 50% inhibitory concentration (IC50) value ranging from 7.5 to 350 µg/ mL. The percentage radical scavenging activities of samples were compared to the standard butylated hydroxytoluene (BHT). The antioxidant activity of extracts and BHT in increasing order was HI‑ME < AP‑ME < TP‑EE < BHT < AC‑ME. A positive correlation was observed between antioxidant activity and TPCs. The results suggested that the phenolic compounds in extracts are most likely to be responsible for the observed antioxidant activity. Key words: Antioxidant activity, correlativity, 2,2‑diphenyl‑1‑picrylhydrazyl assay, medicinal plants, phytochemicals, total phenolic contents

Antioxidant Activity of Milling Fractions of Selected Cereals

Antioxidant Activity of Milling Fractions of Selected CerealsThe aim of this study was to evaluate antioxidant potential of four milling fractions of selected cereals grew in the year 2009 and 2010. Free radical scavenging activity of samples was measured using DPPH assay and reducing power was determined using FRAP assay. Secondary, total phenolic and flavonoid content of cereal extracts was evaluated. We found that flour fractions (break flour and reduction flour) showed the lower proportion of the total antioxidant potential than bran fractions (fine bran and coarse bran), which was balanced in observed years. Extract from barley had the highest values of antioxidant activity and polyphenol content.

Enrichment and purification of flavones from rhizomes of Abacopteris penangiana by macroporous resins

AimTo investigate the enrichment and purification of flavones from the rhizomes of Abacopteris penangiana (RAP) by macroporous resins. MethodsStatic adsorption and desorption tests were performed to select the appropriate resin. The kinetic adsorption and desorption experiments were carried out on selected HPD500 resin to optimize the separation process of flavones. Additionally, the effects of four parameters including adsorption flow rate, elute flow rate, volume of water and ethanol solution for elution were explored by a L4/3 orthogonal experiment. Finally, the ABTS (2, 2′-azinobis-3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activities of samples before and after being treated by HPD500 were compared. ResultsThe results showed that the optimal parameters were initial concentration of 2.86 mgmL−1, elute solution of 70% ethanol, absorb flow rate of 1 mLmin−1, elute flow rate of 2 mLmin−1, 5 BV of water for elution and 5 BV of ethanol solution for elution. ConclusionThe content of flavones is above 60% in RAP after being treated by HPD500, indicating that macroporous resins could be successfully applied to enrich and purify flavones in RAP.

옥수수수염 분말의 입자크기별 이화학적 특성과 항산화활성

본 연구에서는 옥수수수염을 일반분쇄기와 저온초미분쇄기를 이용하여 얻은 5단계의 다른 입자 크기의 옥수수수염 분말을 각각의 입자 크기별 이화학적 특성을 검토하고 항산화활성을 평가하여 최적의 입자크기를 찾고 우수한 가공법을 확립하고자 연구를 수행하였다. 본 연구의 결과를 요약하면 다음과 같다. 1. 건조된 옥수수수염을 일반적 분쇄 방법과 저온초미분쇄기를 이용하여 분쇄한 5단계의 입자크기는 각각 <TEX>$199.17{\mu}m$</TEX>, <TEX>$178.27{\mu}m$</TEX>, <TEX>$85.48{\mu}m$</TEX>, <TEX>$27.04{\mu}m$</TEX> 및 <TEX>$20.97{\mu}m$</TEX>로 가장 큰 입자 크기와 가장 작은 입자 크기와는 약 10배 가량 입자크기의 차이가 있었다. 2. 입자크기별 옥수수수염 분말의 색차는 입자의 크기가 작아질수록 명도와 황색도의 수치가 커졌다. 3. 또한 입자크기별 옥수수 수염 분말을 주사전자현미경(SEM)을 이용하여 300배 확대하여 관찰한 결과 입자의 크기가 작아질수록 확대한 입자의 크기가 작은 것을 확인할 수 있었으며 입자의 모양은 다각형의 모양을 보였다. 4. 입자크기별 옥수수수염 분말의 조지방, 조섬유, 조회분, 조단백질 함량과 유리당 함량을 분석한 결과 조섬유 함량과 조단백질 함량은 입자크기가 작아질수록 그 수치가 줄어들었고, 조지방 함량과 조단백질 함량, 유리당 함량은 입자크기 간에 유의적인 차이를 보이지 않았다. 5. 입자크기별 옥수수수염 분말의 총 페놀 함량과 DPPH 라디컬 소거능 모두 입자크기가 작아질수록 그 수치가 증가하였고 통계적으로도 유의적인 차이를 보였다. 6. 옥수수수염 분말의 입자크기에 따른 ascorbic acid equivalents는 입자크기간의 수치적으로는 차이가 있는 것으로 보였으나 통계적으로는 서로간의 유의적 차이가 없는 것으로 나타났으나 TEAC 실험과 FRAP 실험에서는 입자크기가 작아질수록 그 수치가 증가하였고 통계적으로도 유의적인 차이를 보였다. 7. 옥수수수염 분말의 입자크기, 색도, 이화학적 특성 및 항산화 활성간의 상관관계를 분석한 결과 서로 유의적 관계를 보였으며 특히 입자크기가 작아질수록 명도, 적색도, 황색도, 총 페놀 함량, ascorbic acid equivalents, TEAC에서 고도로 유의한 상관관계를 보였다. The study was carried out to analyze the relationship between analysis of antioxidant activity and the level of functional components according to particle size of corn silk. Particle size was classified into 5 groups. By particle size distribution and color difference, the total phenol content and DPPH radical scavenging activity were observed. The particle sizes of corn silk were <TEX>$199.17{\mu}m$</TEX>, <TEX>$178.27{\mu}m$</TEX>, <TEX>$85.48{\mu}m$</TEX>, <TEX>$27.4{\mu}m$</TEX> and <TEX>$20.97{\mu}m$</TEX>, respectively. The lightness of colored pigments was increased when the particle size was decreased. The contents of free sugar (fructose, glucose, galactose, sucrose, and maltose) of corn silk were analyzed using a HPLC. The total phenol contents by the particle sizes of corn silk were 2.01 mg/g, 2.02 mg/g, 2.06 mg/g, 2.26 mg/g and 2.26 mg/g, respectively. DPPH radical scavenging activities of samples were 21.00%, 21.75%, 22.90%, 24.35% and 23.67%, respectively. Antioxidative activities of Trolox and Fe(II) in corn silk were measured by ferric reducing antioxidant power (FRAP) assay and Trolox equivalent antioxidant capacity (TEAC) assay. TEAC values of samples were <TEX>$2.36{\mu}mol$</TEX> TE / g dw, <TEX>$2.81{\mu}mol$</TEX> TE / g dw, <TEX>$3.20{\mu}mol$</TEX> TE / g dw, <TEX>$3.36{\mu}mol$</TEX> TE / g dw, and <TEX>$3.44{\mu}mol$</TEX> TE / g dw, respectively. FRAP values of samples were <TEX>$11.67{\mu}mol$</TEX> Fe(II) / g dw, <TEX>$12.80{\mu}mol$</TEX> Fe(II) / g dw, <TEX>$13.43{\mu}mol$</TEX> Fe(II) / g dw, <TEX>$13.85{\mu}mol$</TEX> Fe(II) / g dw and <TEX>$15.95{\mu}mol$</TEX> Fe(II) / g dw, respectively. Total phenolic content and antioxidantive activities based on FRAP assay and TEAC assay were increased with decreasing particle size. In addition, DPPH radical scavenging activity was also increased. A significant correlation was also noted between DPPH radical scavenging activities and the content of phenolic compounds.

The evaluation of antioxidant activity of milling fractions of selected cereals grown in the year 2010

Cereals are good source of biologically active compounds that contribute to reducing the risk of coronary heart disease and also inhibit oxidation in human plasma. The aim of this study was to evaluate of antioxidant potential of four milling fractions of selected cereals grown in the year 2010. Methanol was used to extract the antioxidant compounds from cereals. Free radical scavenging activity of samples was measured using DPPH assay and reducing power was determined using FRAP assay. Secondary was evaluated of total phenolic and flavonoid content of cereal extracts. We found that flour fractions (break flour and reduction flour) showed the lower proportion of the total antioxidant potential than bran fractions (fine bran and coarse bran). Extract from barley had the highest values of antioxidant activity and phenolic content.

Study on Antioxidant Activity of Aqueous Extracts from Scum of Mixed Juice

The scum of mixed juice is a by-product in sugarcane factory, which used up-floating method for mixed juice clarification. The scum is of great research and utilization value due to its rich organic non-sugar compounds such as proteins, lipids and polyphenols. Studies on the free radical scavenging capacity and reducing power of water extraction sample (A) and macroporous resin purified sample (B) from mixed juice scum were investigated, comparing with Vc. It was showed that the antioxidant activity of macroporous resin purified sample (B) was much stronger than that of water extraction sample (A) and Vc in , and system. For example, the scavenging capacity of sample B on was 11 times than that of Vc and 1450 times of sample A. In addition, the free radical scavenging activity of sample A and B was dependent on the sample concentration. Results in this study indicated that scum of mixed juice may be a promising natural antioxidant, which can be used as additives in food industry or feed industry.

Changes in Protein Quality and Antioxidant Properties of Buckwheat Seeds and Groats Induced by Roasting

This study focused on the evaluation of changes in protein quality and antioxidant properties of buckwheat seeds and groats induced by roasting. Changes in protein quality were indirectly measured by Maillard reaction chemical indicators such as furosine, FAST index, and browning. Characterization of antioxidant profiles of raw whole seeds, roasted whole seeds, raw groats, and roasted groats was undertaken by determining the extractable total phenolic compounds (TPC), extractable total flavonoids (TF) and individual flavonoids, lipophilic and hydrophilic peroxyl radical scavengers by ORAC(FL) assay, and scavengers of ABTS radical cations by TEAC assay. Roasting significantly decreased the total protein content of groats, whereas this parameter was not affected by the thermal treatment of whole seeds. The formation of MRPs was induced by the thermal treatment of both whole seeds and groats, thus suggesting deterioration of protein quality due to this chemical event. A significant degradation in natural antioxidants due to thermal processing was observed. Most of the peroxyl radical scavenging activity of samples was associated with hydrophilic compounds because L-ORAC(FL) values were on average 9% of the H-ORAC(FL) values. The H-ORAC(FL) values were positively correlated with extractable TPC contents (r = 0.51) and extractable TF contents (r = 0.93), whereas they showed a negative correlation with furosine (r = -0.87), FAST index (r = -0.85), and browning (r = -0.98) results.

Content of selected bioactive components and antioxidant properties of broccoli (Brassica oleracea L.)

To evaluate individual variations in broccoli VOLTA F1 plants, the bioactive components of 15 florets that were cultivated in identical agricultural and climatic conditions were analyzed. Glucosinolates were analyzed by HPLC; total phenolic compounds, ascorbic and dehydroascorbic acids (vitamin C) and the DPPH• and OH• radical-scavenging activities of samples were also determined. Florets were characterized by particularly high glucoraphanin content, 17.95 μmol/g dry weight on average, which comprised about 50% of total glucosinolates. High individual variation was observed for several bioactive compounds, as well as for DPPH• and OH• radical-scavenging activity. Coefficients of variability (CVs) were high, and except for one case, exceeded 10%. Among glucosinolates, the highest CVs were noted for progoitrin (34.22%), 4-hydroxyglucobrassicin (27.32%) and neoglucobrassicin (24.44%). High CVs were also observed for vitamin C (29.11%), including dehydroascorbic acid (26.72%), and for OH• (25.76%) and DPPH• (21.77%) radical-scavenging activities. Smaller variations were found for glucoraphanin (CV = 14.84%) and polyphenols (CV = 14.95%).