High Levels Of Antioxidant Activity Research Articles

Biological Evaluation and Application of Fermented Miang ( Camellia sinensis Var. assamica (J.W.Mast.) Kitam.) for Tea Production

Fermented Miang is a traditional masticatory snack of the northern people of Thailand. The aim of this study is to collect data concerning the length of fermentation and maturity of leaves (A01, A02, B01, B02, C) to determine total phenolic content and antioxidant activity. A01 and B02 were selected for drying (A01D and B02D) since it was higher in total phenolic content and antioxidant activity. The results showed that dried young fermented Miang (B02D) possessed higher GAE and TEAC values than A01D. It was developed as a tea product. Then Miang tea product was screened for pharmacological activities. It was found that dried Miang tea product showed a high level of antioxidant activity with TEAC = 216.0 mg/mg DW tea and showed the ability to scavenge O2- activity at IC50= 0.038 mg/ml. Furthermore, it showed the capability to inhibit tyrosinase and hyaluronidase including anti-glycation activity.

Screening chemical composition of essential oils and antioxidant activities of two Artemisia species from Iran .

Essential oils of two wild-growing Artemisia species collected from west of Iran during the flowering stage were obtained by hydro-distillation and analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC–MS). Under the optimum extraction and analysis conditions, 23 and 19 constituents were identified in A. fragrans and A. hausskenechtii which represented 92.96% and 90.20% of the oils, respectively. The main constituents of A. hausskenechtii were camphor (42.50), 1,8-cineol (20.91 %) and isoborneol (7.27%). Chrysanthenone (41.05%), 1,8-cineol (11.09%), and n-pentane (9.07%) were the major components of essential oils in A. fragrans. Antioxidant activity was assayed by two complementary test systems, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and β-carotene/linoleic acid systems. Antioxidant activity of polar sub-fraction of A. hausskenechtii was found to be higher than those of the others in DPPH assay while essential oil in A. hausskenechtii had the highest level of antioxidant activity in β-carotene/linoleic acid test (54.2± 0.5 μg/ml and 80.2±0.8% inhibition rate, respectively).

Preparation and characterization of quercetin/dietary fiber nanoformulations

Quercetin is well known for its beneficial health effects on the human body. However, the slow dissolution rate leading to poor bioavailability constitutes a barrier to being further developed for nutritional products. In this work, quercetin was co-precipitated with dietary fibers into a fast-dissolving nanoformulation via antisolvent precipitation, followed by spray drying. With the help of cellulose fiber, resistant starch or resistant maltodextrin, a high dissolution rate and good storage stability was achieved for quercetin nanoformulations. In addition, nanoformulations exhibited higher level of antioxidant activities in contrast to raw quercetin. The developed quercetin/dietary fiber nanoformulations could be used as supplements or functional ingredients for food development.

Effects of genotype and environment on avenanthramides and antioxidant activity of oats grown in northwestern China

To investigate the effects of genotype and growing environment on avenanthramides and antioxidant activity of oats, the total phenolic content (TPC), avenanthramide compositions, and antioxidant activity were determined for whole oat from 39 cultivars grown in four locations in northwestern China (Inner Mongolia, Qinghai, Shanxi and Gansu). The results demonstrated that environment (E), genotype (G) and the interaction of these factors (E × G) significantly affected TPC, concentration of avenanthramide 2c (2c, ranged from 6.24 to 136.20 mg kg−1), avenanthramide 2p (2p, 6.07–112.25 mg kg−1), avenanthramide 2f (2f, 7.26–222.77 mg kg−1) and antioxidant activity of oats. The effect of E was considerably greater than that of G or E × G. Based on G plus G × E interaction biplots (GGE biplots) analysis, the four locations in northwestern China can be divided into either two or three regions. Qinghai was determined to be distinct from the other locations. Cultivar Bayou 9 and oats grown in Gansu exhibited the highest TPCs, concentrations of 2c, 2p, 2f and antioxidant activity. The results suggest that oats containing more avenanthramides and exhibiting high levels of antioxidant activity could be obtained by selecting an appropriate genotype and growth location.

Pruning maqui (Aristotelia chilensis (Molina) Stuntz) to optimize fruit production

Maqui (Aristotelia chilensis (Molina) Stuntz) is a wild tree native to Chile with one of the highest levels of antioxidant activities known. The increasing demand for its fruit is all coming from wild collection. The ongoing domestication process is seeking for better fruit quality and sustainability of the production. The present research studies the response of cultivated maqui to different pruning treatments: spring heading, summer heading and renewal cuts. Spring pruning favored the appearance of vegetative and reproductive shoots. This treatment also improved the fruit yield of the following season compared with summer pruning. Vegetative shoots sprout mainly on two year old branches, while reproductive shoots appear also from recently grown plant sections. To achieve high fruit yields, maqui should be pruned in spring and branches renewed constantly to maintain a small plant size.

Influence of pre-harvest red light irradiation on main phytochemicals and antioxidant activity of Chinese kale sprouts.

The effects of pre-harvest red light irradiation on main healthy phytochemicals as well as antioxidant activity of Chinese kale sprouts during postharvest storage were investigated. 6-day-old sprouts were treated by red light for 24h before harvest and sampled for further analysis of nutritional quality on the first, second and third day after harvest. The results indicated that red light exposure notably postponed the degradation of aliphatic, indole, and total glucosinolates during postharvest storage. The vitamin C level was remarkably higher in red light treated sprouts on the first and second day after harvest when compared with the control. In addition, red light treatment also enhanced the accumulation of total phenolics and maintained higher level of antioxidant activity than the control. All above results suggested that pre-harvest red light treatment might provide a new strategy to maintain the nutritive value of Chinese kale sprouts during postharvest storage.

Resveratrol and Epigallocatechin-3-gallate addition to thawed boar sperm improves in vitro fertilization

Thawing is one of the most delicate process after semen cryopreservation as spermatozoa pass from a dormant metabolic stage to a sudden awakening in cellular metabolism. The rapid oxygen utilization leads to an overproduction of reactive oxygen species that can damage sperm cells, thus causing a significant decrease of fertilizing potential of frozen-thawed spermatozoa. Resveratrol (Res) is a natural grape-derived phytoalexin and Epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea (Camellia sinensis); both molecules are known to possess high levels of antioxidant activity. The objective of the present study was to assess the effect of different concentrations of Res (0.5, 1 or 2 mM; Experiment 1) or EGCG (25, 50 or 100 μM; Experiment 2) supplementation to thawing boar semen extender on sperm quality parameters (viability and acrosome integrity) and in vitro fertilization (IVF). Semen after thawing and dilution with three volumes of Beltsville Thawing Solution (BTS), was immediately divided in control group without antioxidants addition (CTR) and either Res or EGCG groups. Sperm viability and acrosome integrity were evaluated in CTR, Res or EGCG groups after 1 h of incubation at 37 °C. The addition of different doses of Res or EGCG to thawing extender for 1 h did not induce any effect on boar sperm viability and acrosome integrity. However, both Res and EGCG treated samples exhibited a significantly higher penetration rate compared with CTR when used for IVF. In particular the treatment with all the EGCG concentrations increased the penetration rate (P < 0.01) while only Res 2 mM induced a significant increase of this parameter (P < 0.01). In addition, EGCG 25 and 50 μM supplementation significantly increased total fertilization efficiency as compared to control (EGCG 25 μM: 40.3 ± 8.2 vs 26.8 ± 9.5, P < 0.05; EGCG 50 μM: 40.4 ± 7.8 vs 26.8 ± 9.5, P < 0.01). The same effect was observed with Res 2 mM (51.0 ± 7.6 vs 29.6 ± 11.3, P < 0.01). In conclusion, our results indicate that the addition of different doses of the two antioxidants to thawed spermatozoa for one hour, even if does not exert any effect on sperm viability and acrosome integrity, efficiently improves in vitro penetration rate. Moreover, both molecules (EGCG 25 and 50 μM and Res 2 mM) significantly increases the total efficiency of fertilization.

English

Coffea arabica (Arabica) and Coffea canephora (Robusta) are the economic plants in Thailand that are widely cultivated in Northern and Southern Thailand. This study aims to evaluate the antioxidant, anti-tyrosinase activities, toxicity, stability and identify chemical components of the coffee bean extracts. The best extract that showed good biological activities will be further used to develop cosmeceutical products. Green and roasted coffee beans from two species were extracted with hexane following ethanol by maceration. Their antioxidant activities were detected by 2,2-diphenyl-1-picryl hydrazyl (DPPH), 2,2&rsquo;-Azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and lipid peroxidation inhibition assays. In addition, anti-tyrosinase activity was also evaluated. The results revealed that the ethanolic coffee bean extracts showed a higher level of antioxidant activity than in the hexane extracts. All extracts also possessed a considerable anti-tyrosinase activity, but less potent than kojic acid and arbutin. Chemical compounds of these extracts were determined using caffeine and chlorogenic acid as standards of reference by the thin layer chromatography and the high performance liquid chromatography. The green coffee bean extracts consisted of caffeine and chlorogenic acid while the roasted coffee bean extracts presented only caffeine due to a few chlorogenic acid content after the roasting process. The ethanolic coffee bean extracts that showed good activities were selected to be evaluated on toxicity and stability. The selected extracts were kept at various storage conditions to evaluate their stability using DPPH assay and anti-tyrosinase activity assay. The result showed that the extracts were not toxic to cells. Therefore, the extracts were safe to be components in skin care products. After the stability test, the extracts indicated a good stability and activities. These results led to the conclusions that the coffee bean extracts possess a good biological activities and are assumed to be promising natural active ingredients with a good stability profile for further development of cosmeceutical or anti-aging products. Key words: Coffea arabica, Coffea canephora, green coffee bean, roasted coffee bean, antioxidant activity, anti-tyrosinase activity.

Green method for determination of phenolic compounds in mung bean (Vigna radiata L.) based on near‐infrared spectroscopy and chemometrics

SummaryMung bean grains exhibit high level of antioxidant activity due the presence of phenolic compounds. Near‐infrared spectroscopy (NIRS), in conjunction with chemometrics, was used to develop a rapid, nondestructive, chemical free and easy‐to‐use method to determine these compounds in sixty genotypes of mung bean. NIRS calibration curve with high‐performance liquid chromatography (HPLC) as reference method was used to determine phenolic compounds (catechin, chlorogenic acid, caffeic acid, p‐coumaric acid, t‐ferulic acid, vitexin, isovitexin, myricetin, quercetin and kaempferol). It was observed that partial least square regression (PLSR) model in the wavelength range of 1600–2500 nm with standard normal variate (SNV) and linear baseline correction (LBC) as preprocessing techniques can measure phenolic compound accurately (R2 &gt; 0.987) with root‐mean‐square error less than 1.82%. This study shows that NIRS along with chemometrics is an accurate method to estimate the phenolic compounds rapidly and nondestructively.

Quality Parameters and Antioxidant Activity of Three Clover Species in Relation to the Livestock Diet

Products of metabolism that are directly involved in growth, development and reproduction and also secondary products of metabolism were studied in 16 natural populations of three species of the genus Trifolium (T. repens – four populations, T. alpestre – three populations, T. pannonicum – nine populations), collected from the central Balkans region, i.e. territory of Serbia. Statistical analysis showed the presence of variability in all species of the test material. The best quality of dry matter, estimated by the ratio of crude protein and crude fiber, was achieved in the populations of white clover. In this species, average protein content was 216.4 g kg-1 while the average content of crude fiber was 222.4 g kg-1. The highest average content of total phenols (77.9 mg GA g-1), flavonoids (159.7 mg Ru g-1) and antioxidant activity (70.2 μg ml-1) was measured in populations of T. pannonicum by phytochemical analysis of aerial parts of plants. The content of secondary metabolites and antioxidant activity in other species were extremely low. Populations of T. pannonicum were notable for fodder quality and antioxidant activity: CS091 with 186.2 g kg-1 of crude protein and antioxidant activity of 55 μg ml-1; RA123 with 175.6 g kg-1 of crude protein and a high level of antioxidant activity of 44.8 μg ml-1. It can be concluded that the selection of these populations may lead to creation of different varieties of fodder crops that could give safe animal feed and would be suitable for growing under adverse conditions of mountainous climate.

Influence of ozonated water sanitation on postharvest quality of conventionally and organically cultivated mangoes after postharvest storage

We investigated the alterations on bioactive compounds after treatments with ozonated water during the storage of organically and conventionally cultivated mangoes, cv. Palmer. Mangoes were stored in a cold chamber (14±2°C) for 15 d and evaluated after the harvest and sanitization treatments (chlorine and ozonated water—10 and 20min) at 7 and 15 d. To simulate the market, after 7 d, mangoes were removed from cold storage and kept at room temperature (27±2°C) to be analyzed following 4 (7+4) and 8 (7+8) d at room temperature. The conventionally mango showed higher firmness, regardless of the sanitization system used. Ozonated water did not alter the levels of β-carotene, ascorbic acid, dehydroascorbic acid and phenol in organically or conventionally cultivated mangoes during storage, but when the mangoes, cv. Palmer were transferred to room temperature, the β-carotene level increased. Organically cultivated mangoes showed higher levels of antioxidant activity. Ozonated water can be used as an alternative to chlorine sanitizer without causing damage to mango, cv. Palmer fruit or inducing a decrease in the various compounds and the treatment using ozonated water was efficient for maintaining fruit without microorganisms, preventing the reduction of quality and avoiding the generation of organic waste.

A 2-Cys peroxiredoxin in response to oxidative stress in the pine wood nematode, Bursaphelenchus xylophilus.

The pine wood nematode, Bursaphelenchus xylophilus, is the causal agent of pine wilt disease that has devastated pine forests in Asia. Parasitic nematodes are known to have evolved antioxidant stress responses that defend against host plant defenses. In this study, the infestation of whitebark pine, Pinus bungean, with B. xylophilus led to a significant increase in plant hydrogen peroxide (H2O2) and salicylic acid levels. Correspondingly, the expression of an antioxidative enzyme, 2-Cysteine peroxiredoxin (BxPrx), was elevated in B. xylophilus following the H2O2 treatments. Recombinant BxPrx, a thermal stabile and pH tolerant enzyme, exhibited high level of antioxidant activity against H2O2, suggesting that it is capable of protecting cells from free radical attacks. Immunohistochemical localization study showed that BxPrx was broadly expressed across different tissues and could be secreted outside the nematode. Finally, the number of BxPrx homologs in both dauer-like and fungi-feeding B. xylophilus were comparable based on bioinformatics analysis of existing EST libraries, indicating a potential role of BxPrx in both propagative and dispersal nematodes. These combined results suggest that BxPrx is a key genetic factor facilitating the infestation and distribution of B. xylophilus within pine hosts, and consequently the spread of pine wilt disease.

Antioxidant activity and phenol content of extracts of bark, stems, and young and mature leaves from Blepharocalyx salicifolius (Kunth) O. Berg.

Phenolic compounds are a group of plant secondary metabolites known to have a variety of bioactivities, including the ability to function as antioxidants. Because of the side effects of the use of synthetic substances, the search for natural and less toxic compounds has increased significantly. This study was designed to evaluate the antioxidant activity and phenol content of hexane, ethyl acetate, and aqueous extracts of the bark (suber) and stems as well as the young and mature leaves of Blepharocalyx salicifolius. The extracts were obtained by extraction with organic solvents and subsequent fractionation by chromatographic partition coefficient. Preliminary tests for the presence of antioxidants were performed using bioautography in thin-layer chromatography. The antioxidant activity of the extracts was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, and the phenol content of the extracts was quantified using the Folin-Ciocalteu technique. The results showed that 9 of the 12 extracts evaluated displayed very strong antioxidant activity and three displayed moderate activity. Aqueous extracts of the young leaves and bark and the ethyl acetate extract of the young leaves showed the highest levels of antioxidant activity and total phenolic content (TPC). A correlation was observed between TPC and antioxidant activity index (AAI) with a correlation coefficient (r2) of 0.7999. Thus, the high phenol content of B. salicifolius extracts and its correlation with antioxidant activity provide substrates for further studies.

Enhancement of storage quality and antioxidant capacity of harvested sweet cherry fruit by immersion with β-aminobutyric acid

Freshly harvested sweet cherry fruit were immersed with 30mmolL−1 β-aminobutyric acid (BABA) for 10min and then stored at 20°C for 5 d to investigate the effect of BABA on quality and antioxidant activity. The results showed that BABA-treated cherries had lower respiration rates and weight loss and higher levels of titratable acidity, total phenolics, ascorbic acid, fructose, glucose, sucrose, malic, citric and succinic acids compared with that in control fruit. BABA treatment inhibited the decrease of L* value of fruit pericarp and chlorophyll contents of fruit peduncles. BABA enhanced the antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) throughout the storage period. In addition, BABA-treated fruit exhibited higher levels of antioxidant activity as measured by the scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide and hydroxyl radicals, and by the reducing power test compared to the control. These results indicate that postharvest application of BABA immersion can improve the organoleptic and nutritive qualities and enhance the antioxidant capacity of harvested sweet cherry fruit.

Effect of Induced Mutation on Antioxidant Activity in &amp;lt;i&amp;gt;Ocimum basilicum&amp;lt;/i&amp;gt; Linn

Five batches from the same stock of seeds of Ocimum basilicum were irradiated at 5, 10, 15, 20 and 25 Gy, respectively using 60C source. Methanolic leaf extracts of these samples and a control were evaluated for their antioxidant activity by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging method using M2 plants. All the methanolic extracts showed antioxidant activity. The IC50 of the methanolic extracts of the six different treatments, control, 5 Gy, 10 Gy, 15 Gy, 20 Gy and 25 Gy, showed antioxidant activity with IC50 values of 100, 90, 86, 61, 71 and 70 μg/ml, respectively. Three individual mutants, M-15-5, M-20-6 and M-15-4, had IC50 values of 26, 30 and 40 μg/ml, respectively. These mutants were from the 15 Gy and 20 Gy treatments. From the results, it is confirmed that induced mutation can be employed to create variation in the levels of free radical scavenging activity in O. basilicum and can therefore serve as a tool for breeding for high levels of antioxidant activity in O. basilicum.

Assessment oxidative stress biomarkers and metal bioaccumulation in macroalgae from coastal areas with mining activities in Chile.

The aim of this study was to evaluate the effect on seaweeds Scytosiphon lomentaria and Ulva rigida of coastal waters of sites with mining activity, using oxidative stress biomarkers and heavy metal determination both in water and in tissue. The greatest bioaccumulation factors in S. lomentaria and U. rigida were founded for iron and arsenic in Quintay. Bioaccumulation factor in S. lomentaria in descending order was Fe> Cu> Zn> Cd> Cr> As> Mo and in U. rigida, in descending order, was Fe> Cu> Cd> Zn> Cr> Mo> As. Both species had higher antioxidant activity levels in areas with high mining activities. The concentration of metals in waters such as copper and arsenic in S. lomentaria, and iron, arsenic, and cadmium in U. rigida were related with oxidative stress biomarkers measured in both species. The use of both species is proposed to monitor the bioavailability and oxidative damage in coastal areas with mining activity. This work will generate a significant knowledge about the impact of mining wastes on macroalgal community in the area of north-central Chile.

Cooking techniques improve the levels of bioactive compounds and antioxidant activity in kale and red cabbage

The aim of this study is to investigate the effects of different home cooking techniques (boiling, steaming, and stir-frying) in kale and red cabbage, on the levels of bioactive compounds (carotenoids, anthocyanins and phenolic compounds) determined by high-performance liquid chromatography coupled with photodiode array and mass spectrometry detectors (HPLC–DAD–MSn), and on the antioxidant activity evaluated by ABTS, ORAC and cellular antioxidant activity (CAA) assays. The steaming technique resulted in a significant increase in phenolic content in kale (86.1%; p<0.001) whereas in red cabbage it was significantly reduced (34.6%; p<0.001). In the kale, steaming resulted in significant increases in antioxidant activity levels in all of the evaluation methods. In the red cabbage, boiling resulted in a significant increase in antioxidant activity using the ABTS assay but resulted in a significant decrease using the ORAC assay. According to the CAA assay, the stir-fried sample displayed the highest levels of antioxidant activity.

New acylated anthocyanins from purple yam and their antioxidant activity.

Purple yam (Dioscorea alata L.), which is widely distributed in tropical and subtropical regions, is characterized by its color and viscosity. Previous studies have shown that purple yams contain a variety of acylated anthocyanins that exhibit higher levels of antioxidant activity than the corresponding nonacylated compounds. In this study, the pigments found in purple yams from the Philippines (D. alata) were isolated and evaluated in terms of antioxidant activity. Four new acylated anthocyanins, alanins (1-4) were isolated from the MeOH extracts of purple yam, which were subsequently determined to be cyanidin (1, 2, and 4) and peonidin (3) type compounds, along with four known anthocyanins (5-8). The structures of 1-4 were determined by spectroscopic methods, including NMR and MS analyses. The antioxidant activities of anthocyanins 1-8 were investigated using oxygen radical absorbing capacity and ferric reducing antioxidant power assays.

The Fatty Acid Profile and Phenolic Composition of Descurainia sophia Seeds Extracted by Supercritical CO2

AbstractOil and phenolics were extracted from Descurainia sophia (Sophia) seeds by a supercritical CO2 system. Extractions were conducted in two sequential steps, first using 100 % CO2 and then adding 10 % ethanol as co‐solvent. The extracts were collected in each step using two separate collectors operating at different pressures. The extraction run was 3 and 4 h for the first period, and 2 h for the second period. The majority of the oil was collected in the first extraction period while phenolic compounds were obtained in the second extraction period. A combined mode of static/dynamic extraction (3 h running and 1 h soaking in CO2) was also used in the first extraction period, which enhanced the total extraction yield (29.3 ± 0.5 %) and was comparable to the 4 h extraction yield (31.4 ± 0.1 %). The total fatty acid (FA) content of oil in collector 1 (0.94 g) was nearly twice that in collector 2 (0.60 g). The oil contained 14 FAs with α‐linolenic being predominant (48.5 %), with a total 91.1 % unsaturated FAs, a ω3/ω6 ratio of 2.7, and an erucic acid content of 6.2 %. More than 10 phenolic compounds were detected by HPLC in the Sophia seed extracts of which sinapic acid was the dominant compound. Sophia seed extracts showed high levels of antioxidant activity. These results suggest that Sophia seed oil and phenolics have the potential for functional food and pharmaceutical applications.

Sunlight Induces Black Color and Increases Flavonoid Levels in the Grain of Sorghum Line Tx3362

ABSTRACTThe grain sorghum [Sorghum bicolor (L.) Moench.] line ‘Tx3362’ has a uniformly black pericarp color when produced under summer production conditions and it also contains high levels of 3‐deoxyanthocyanidins (3‐DOAs) in the bran layers of the grain. Consequently, Tx3362 has high levels of antioxidant activity and is a source of natural pigmentation that can be used as natural food coloring. However, prior research indicates that the black color is not fully penetrant in all environments. Specifically, black sorghum panicles shaded from sunlight between flowering and physiological maturity are dark red in color. The objective of this study was to determine if the time of light exposure affects pericarp color, 3‐DOA production, and other grain composition traits. Three experiments were conducted that shaded developing Tx3362 black sorghum panicles for varying time intervals in two Texas environments. After harvest, samples were visually phenotyped, quantitatively measured for color via colorimeter, and analyzed using near‐infrared spectroscopy (NIR) to estimate grain composition values. Across both environments, increased shading reduced and, in some cases, eliminated the black color, resulting in red grain. In addition, increased shading reduced the concentration of 3‐DOA, total phenols, tannins, and fiber but increased fat concentrations. Because of the strong association between visual score and 3‐DOA concentration, field selection for the darkest pericarp should result in selection for the highest 3‐DOA content. Additionally, maximum production of these beneficial compounds is environment‐specific. Therefore, environments with high sunlight intensity are conducive to the production of darker grain and higher 3‐DOA, tannin, and phenol content.