Variation in Antioxidants,Bioactive Compounds and Antioxidant Capacity in Germinated and Ungerminated Grains of Ten Rice Cultivars

Present study was conducted to characterise ten rice(Oryza sativa L.) cultivars viz. IET-23466, Dhan-201, IET-23448, MAS-946, IET-23445, IET-23463, IET-23455, PR-123, PR-115 and IET-23449 based on antioxidants(total phenolics, flavonols and tannins), bioactive compounds(phytic acid, gamma amino butyric acid, tocopherol and reduced ascorbate) and antioxidant activity(1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, hydroxyl radical scavenging activity, free radical antioxidant power and total reducing power) with an aim to identify cultivars containing higher health promoting components after germination. Three cultivars IET-23466, IET-23463 and PR-123 performed better as revealed by higher level of antioxidants, bioactive compounds and antioxidant activity before and after germination. Three cultivars MAS-946, IET-23445 and IET-23449 had moderate level of antioxidants, bioactive compounds and antioxidant activity. Four cultivars Dhan-201, IET-23448, IET-23455 and PR-115 performed intermediately. Strong positive correlation was observed among total phenolics and the antioxidant activity. Phytic acid was found to be negatively correlated to the antioxidant activity. Our results highlighted that cultivars IET-23466, IET-23463 and PR-123 hold great potential after germination and would open up a useful opportunity for the functional food industry, and consumption of these cultivars after germination would afford health benefits to consumers since they contain higher level of antioxidants.     

A study of biodiversity of flavonoid content in the rice caryopsis evidencing simultaneous accumulation of anthocyanins and proanthocyanidins in a black-grained genotype

Rice genotypes with pigmented caryopses have received increased attention because of their antioxidant properties. Previous works evidenced that the kernel of red rice is characterized by the presence of proanthocyanidins, whereas black rice is characterized by the presence of anthocyanins. In the present study, the total antioxidant capacity (TAC) and the polyphenol content of the caryopsis were evaluated on a set of Italian rice varieties (three white, two black and five red ones). The pigmented rices, on average, had a TAC four times higher than the white ones. As expected, red-grained genotypes contained no detectable anthocyanins and one black rice contained no detectable proanthocyanidins. However, the black-grained cv. Artemide had large amounts of both proanthocyanidins and anthocyanins. This genotype was also characterized by the highest TAC and polyphenol content: its TAC was about twice the TAC of the other pigmented rices, and it had a polyphenol content 2–3 times the content found in the other pigmented rices. Pigmented genotypes are confirmed to be very interesting to breed rice for high polyphenol content and TAC. Furthermore, the possibility to select for genotypes accumulating both anthocyanins and proanthocyanidins provides a way to substantially increase the polyphenol content and TAC of the rice caryopsis.     

Chemical composition, color, and antioxidant activity of three varieties of Annona diversifolia Safford fruits

Annona diversifolia is a Central America native fruit which has become an important crop because of its tasty flavor, high pulp content, nutritional value and antioxidant properties. Color, crude protein, crude fat, crude fiber, ash, minerals, pH, titratable acidity, and carbohydrate contents were determinated in white, pink and deep pink varieties of A. diversifolia. Our results show that the three studied varieties of A. diversifolia could be considered as important sources of fiber, sugars, potassium and zinc. Color measuring was successfully used to objectively characterize the three A. diversifolia varieties, resulting in an excellent agreement with visual observations. The antioxidant activity also was determined and compared. An in vitro study was conducted in terms of vitamin C, total phenols, total flavonoids, and radical scavenging activity. A strong correlation between total polyphenols and radical scavenging activity was observed. This paper reports for the first time the total flavonoid content of Annona genus fruits. In addition, A. diversifolia extracts possessed greater radical scavenging activity and similar total polyphenol content compared to those of other Annona species reported elsewhere.     

Chemical and Functional Characterization of Kañiwa (C<Emphasis Type="Italic">henopodium pallidicaule</Emphasis>) Grain,Extrudate and Bran

Cereals provide a good source of dietary fibre and other important compounds with nutritional potential, such as phenolic compounds, antioxidants, minerals and vitamins. Although native Andean cereals are known to have high nutritional value, their minor components have not been studied thoroughly. In this study, two varieties of a native Andean crop, kañiwa (Chenopodium pallidicaule), were investigated as sources of dietary fibre and specific antioxidant compounds. Two products, an extrudate and bran, were also prepared and their functional properties and bioactive compounds were determined. Both varieties were rich in total dietary fibre and lignin, and the phenolic components analyzed had high antioxidant activity. The extrudates had good functional properties, such as degree of gelatinization, sectional expansion index and water solubility index; the bran was high in bioactive compounds, such as total phenolics. In conclusion, kañiwa may offer an alternative to traditional cereals as a health-promoting food ingredient.     

椰子种皮油提取物的抗氧化活性研究

测定椰子种皮油提取物中的总酚含量,对羟基自由基、DPPH（1,1-二苯基-2-三硝基苯肼）自由基、ABTS（2,2连氮-双-（3-乙基苯并噻咪唑-6-磺酸）自由基清除能力和总抗氧化能力等抗氧化活性指标。结果表明,椰子种皮油提取物中含有较高的总酚含量（68 mg/g）,提取物浓度为0.1 mg/mL时对羟基自由基的清除率为56.89％,对DPPH自由基的清除率为71.0％,对ABTS自由基的清除率为96.4％,表明椰子种皮油提取物具有很好的抗氧化活性。     

Effect of processing conditions on bioactive compounds and glycemic index of the selected landrace rice variety in pre-diabetes

Paddy processing can affect glycemic index (GI) and bioactive compounds of rice. Therefore, the effects of processing conditions such as germination, parboiling and polishing on total polyphenols, ferulic acid and gamma-aminobutyric acid (GABA) contents of seven landrace varieties from Thailand were investigated. Subsequently, the best rice variety was chosen to evaluate GI in pre-diabetic subjects. Four different rice forms used were brown rice (BR), parboiled brown rice (PBR), germinated parboiled brown rice (GPBR) and polished rice (PR). Results showed that polishing process strongly reduced all bioactive compounds. In contrast, parboiling the grains slightly increased polyphenol, and germination followed by parboiling significantly increased polyphenol content. Ferulic acid content was found to be similar among BR, PBR and GPBR and the highest GABA content was found in GPBR. Furthermore, Leuang Awn variety exhibited the highest polyphenol (126.70 ± 1.08 mg GAE/100 g), ferulic acid (17.77 ± 0.16 mg/100 g) and GABA content (78.57 ± 1.00 mg/100 g) and was selected for GI study. PBR and GPBR had medium GI values (55.10 ± 5.37 and 60.58 ± 6.48) and PR showed high GI value (83.10 ± 5.10). In conclusion, parboiling and germination had less effects on the bioactive compounds of whole grain rice and produced low-medium GI, which could be beneficial for health promotion.     

Characterizing the pigmented traditional rice cultivars grown in temperate regions of Kashmir (India) for free and bound phenolics compounds and in vitro antioxidant properties

The purpose of the research was to identify the phenolic and flavonoid compounds of seven different traditional pigmented whole rice cultivars grown in the temperate regions of Kashmir so as to study their relationship with in vitro antioxidant capacities. The completely pigmented rice cultivars were found to have higher phenolic, flavonoid, anthocyanin contents and exhibited higher antioxidant capacities than the light colored and sparely colored rice cultivars. A total of 40 compounds had been identified in the analyzed rice cultivars that were found to be distributed in 6 major categories with 6-phenolics, 6-flavonoids, 11-hydroxycinnamic acid derivatives, 7-hydroxybenzoic acid derivatives, 3-anthocyanins and 7-flavonoid glucosides of different flavonoid compounds. Among the free and bound fractions for each cultivars the light and sparsely colored depicted higher content of phenolics and in vitro antioxidant properties in bound faction, while the completely pigmented cultivars showed higher antioxidant properties in free fractions. The anthocyanins quercetin-3-O-galactoside, cyanidin-3-O-rutinoside and pelargonidin-3-O-diglucoside had been identified by LC-MS existing in the free fractions of the analyzed rice cultivars whereas, the free fraction of acetone + H₂O possessed higher percentage of phenolic compounds as compared to methanolic extracts and bound fractions. The black colored cultivars possessed higher DPPH scavenging activity and lipid peroxidation inhibition.     

Antioxidant properties of wheat and rye bran extracts obtained by pressurized liquid extraction with different solvents

Rye and wheat brans are valuable sources of bioactive compounds, which could be used for the development and commercialization of high added value functional ingredients such as dietary antioxidants. The aim of this study was to evaluate antioxidant potential of rye and wheat bran using different polarity solvents. Cereal brans were ground to four different particle size fractions and extracted at 10.3 MPa pressure and 80 °C temperature by consecutive application of hexane, acetone and methanol:water (80:20%). The highest extract yield was obtained from rye bran using methanol-water; particle size in most cases had a significant effect. Antioxidant potential of extracts was assessed by ABTS^+•, DPPH^• scavenging, ORAC and total phenols content (TPC) assays. Extraction solvent had a major influence on TPC and antioxidant activity of the extracts. The most active extracts were obtained using methanol:water; rye bran extracts, in general, were stronger antioxidants than wheat bran extracts. For the majority of assays, reduction of particle size resulted in higher antioxidant activity values. However, ABTS^+• scavenging was found to decrease by decreasing particle size of rye bran used for extraction.     

Total Phenolic and Phytosterol Compounds and the Radical Scavenging Activity of Germinated Australian Sweet Lupin Flour

In addition to their favourable nutritional profile, legumes also contain a range of bioactive compounds such as phenolic compounds and phytosterols which may protect against chronic diseases including cancer and cardiovascular disease. Germination of some legume seeds has been previously reported to increase the concentration of the bioactive compounds. In this study, the effect of germination of Australian Sweet Lupin (ASL) seeds for 9 days on the concentration of some bioactive compounds and the radical scavenging activity in the resulting flour was determined. The concentration of total phenolic compounds in methanolic extracts of germinated ASL flour was determined using Folin Ciocalteu reagent and phytosterols in oil extracts were analyzed by gas–liquid chromatography. The methanolic and oil extracts were also used to determine radical scavenging activity toward 2,2-diphenyl-1-picrylhydrazyl. In the methanolic extracts of germinated ASL flour, phenolic contents and the antioxidant activity were significantly increased following germination (700 and 1400 %, respectively). Analysis of the oil extracts of germinated ASL flour revealed that the concentration of phytosterols and the antioxidant activity were also increased significantly compared to ungerminated ASL flour (300 and 800 %, respectively). The relative proportion of phytosterols in germinated ASL flour was: β-sitosterol (60 %), stigmasterol (30 %) and campesterol (10 %). Germination increases the concentration of bioactive compounds and the radical scavenging activity in the germinated ASL flour.     

Antioxidant,anti-amylase and anti-glycation potential of brans of some Sri Lankan traditional and improved rice (Oryza sativa L.) varieties

Brans of 23 traditional and 12 improved (both red and white) rice varieties in Sri Lanka were screened for anti-amylase and anti-glycation activities in vitro. Varieties which showed the highest inhibitory activities at screening were further investigated for anti-glucosidase and glycation reversing as anti-diabetic properties. The same varieties were studied for selected antioxidant properties. Significantly high anti-amylase and anti-glycation activities were observed for bran extracts of red varieties compared to white varieties at screening. Traditional red rice varieties, Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti, exhibited significant and dose dependent anti-amylase, anti-glycation and glycation reversing activities. These varieties also showed marked antioxidant properties. It is concluded that brans of Sri Lankan traditional red rice varieties Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti may be potential food supplements for diabetes.     

Antioxidant,anti-amylase and anti-glycation potential of brans of some Sri Lankan traditional and improved rice (Oryza sativa L.) varieties

Brans of 23 traditional and 12 improved (both red and white) rice varieties in Sri Lanka were screened for anti-amylase and anti-glycation activities in vitro. Varieties which showed the highest inhibitory activities at screening were further investigated for anti-glucosidase and glycation reversing as anti-diabetic properties. The same varieties were studied for selected antioxidant properties. Significantly high anti-amylase and anti-glycation activities were observed for bran extracts of red varieties compared to white varieties at screening. Traditional red rice varieties, Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti, exhibited significant and dose dependent anti-amylase, anti-glycation and glycation reversing activities. These varieties also showed marked antioxidant properties. It is concluded that brans of Sri Lankan traditional red rice varieties Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti may be potential food supplements for diabetes.     

Superfine grinding improves functional properties and antioxidant capacities of bran dietary fibre from Qingke (hull-less barley) grown in Qinghai-Tibet Plateau,China

The effect of particle size of hull-less barley (HLB) bran DF on antioxidant and physicochemical properties was investigated. HLB bran and extracted DF was ground by regular and superfine grinding, their particle sizes were determined using laser diffraction method. The results showed that superfine grinding could significantly pulverize DF particles to micro-scale; the particle size distribution was close to a Gaussian distribution. The soluble DF in HLB bran was increased effectively with superfine grinding. Insoluble DF with submicron scale showed increased total phenolic content (TPC), DPPH radical scavenging activity and ferric reducing antioxidant power (FRAP). With particle size reduction, the water retention capacity (WRC), swelling capacity (SC), oil binding capacity (OBC), and nitrite ion absorption capacity (NIAC) were significantly (p < 0.05) increased and the water holding capacity (WHC) had no significant change. A kind of health beneficial DF with higher soluble DF content, WRC, SC, OBC, NIAC and antioxidant activity was obtained using superfine grinding.     

Black currant polyphenols: Their storage stability and microencapsulation

Interest in the consumption of fresh fruits is, to a large extent, due to its content of bioactive nutrients and their importance as dietary antioxidants. There is a growing demand for delivery of antioxidants through functional foods with the related challenge of protecting their bioactivity during food processing and subsequent passage through the gastrointestinal tract. This study focuses on the evaluation of concentration of bioactive compounds in black currant berries (Ribes nigrum L.) and retention of black currant polyphenol compounds and their antioxidant activity after microencapsulation by spray-drying. The polyphenol contents and antioxidant activities were assessed for 5 black currant cultivars grown in Canada in fresh and stored fruits at −20 °C for 9 months. The Ben Alder cultivar was the richest in anthocyanins and flavonols content with high antioxidant potential measured with ABTS and DPPH radicals (4.5 and 2.4 mM/100 g). Black currant polyphenols were stable during 9 month of storage at −20 °C. The results of this study indicated that in black currants storage did not affect negatively the antioxidant capacity. The good stability of bioactive compounds of black currants during freezer storage allows prolonging the storage time of these berries. Maltodextrins with different DE (dextrose equivalent): DE11, DE18, DE21 and inulin were selected as wall material. The stability of encapsulated polyphenols during 12 months storage at 8 °C and 25 °C was evaluated. Compared to maltodextrins DE18 and DE21, maltodextrin DE11 had not only higher drying yield but also offered better protection for phenolics during storage. Radical scavenging activity studies demonstrated significant antioxidant activity of microencapsulated powders before and after storage. The black currant polyphenol microcapsules described in this study represent a promising food additive for incorporation into functional foods due to antioxidant content.     

Effect of solid state fermentation by Enterococcus faecalis M2 on antioxidant and nutritional properties of wheat bran

Wheat bran is the main by-product during wheat flour processing. Although wheat bran is rich in the bioactive compounds and antioxidant capacity, it is not widely utilized in its natural state. To improve the antioxidant and nutritional properties of wheat bran, a dominant strain, Enterococcus faecalis M2, was screened from lactic acid bacteria (LAB) isolated from various foods. Following solid state fermentation, the soluble dietary fiber content of wheat bran nearly quadrupled compared to the raw material. Total proportion of phenols, flavonoids, alkylresorcinols, along with the antioxidant capacity and free radical scavenging rate were significantly improved, particularly the ferulic acid content increased by 5.5 times. Additionally, the free amino acid content increased with degradation of wheat bran protein, whereas the level of anti-nutrient phytic acid decreased. The results of this study could provide an effective method for biological modification of wheat bran, which further enhance the health benefit and utilization of bran.     

基于主成分分析和聚类分析的不同水稻品种营养品质评价研究

为了评价不同颜色糙米品种的营养品质,以3个红米品种、8个黑米品种和8个普通糙米品种为材料,对其5项基本营养成分、13种矿质元素含量和9项活性物质含量等27项营养品质指标进行比较分析,并采用主成分分析和聚类分析对不同水稻品种进行营养品质评价。结果表明,不同品种稻米的总淀粉、膳食纤维和脂肪含量在较小范围内波动;有色米品种的矿质元素含量变化范围较大,普通糙米品种的变化范围较小;总酚、总黄酮、ABTS和DPPH抗氧化活性间存在极显著的相关性,其在有色米品种中的含量显著高于普通糙米品种,且大多数黑米品种的含量显著高于红米品种;总花色苷、矢车菊素-3-O-葡萄糖苷、芍药素-3-O-葡萄糖苷在黑米品种中含量比较高。对稻米基本营养成分和矿物质元素等指标进行主成分分析,提取了6个主成分,其累积方差贡献率达80%左右,可以较好反映稻米的营养品质。对19个水稻品种稻米的所有营养品质参数进行聚类分析,可以将水稻品种分为有色米类和普通糙米类;将所有品质指标分为五类,其两类主要是矿质元素,一类主要是活性物质,两类主要是基本营养成分。该研究结果可为稻米营养品质的评价提供科学依据,也可为生产功能性稻米新产品提供新思路...     

Antioxidant Activities and Characterization of Polyphenols from Selected Northern Thai Rice Husks: Relation with Seed Attributes

Rice production generates a significant amount of agricultural waste. This study aimed to give results related to the existence of antioxidant phenols in agricultural waste of selected Northern Thai rice varieties. The antioxidant activities, contents of total flavonoids and phenolic compounds in the ethanolic rice husk extract were evaluated. The highest antioxidant activities were found in the variety PES1CMU, with 2,2?-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid and 2,2-diphenyl-1-picrylhydrazyl as 679.66 and 4.16 mmol/(L·g) trolox equivalent, respectively, ferric reducing antioxidant power as 0.87 mmol/(L·g) Fe²⁺, total phenolic content as 29.90 mmol/(L·g) gallic acid and total flavonoid content as 12.16 mg/g catechin equivalent. Polyphenol compounds were identified mainly by standard polyphenols using the liquid chromatography mass spectrometry, with the highest contents of phytic acid, o-coumaric acid, naringin and kaempferol. The non-glutenous and wetland ecotypes of rice husk samples were the richest in antioxidant activities and polyphenol contents characterized by using principal component analysis. The glutenous rice husk contained higher antioxidant activities than the rest. Interestingly, quercetin is a significant phenolic compound that positively correlated with the overall antioxidant activities of rice husk. This finding will be relevant for future application of rice husk antioxidant components in the production of functional ingredients as well as for the food and pharmaceutical industries.     

Effects of Polishing on Proximate Composition,Physico-Chemical Characteristics,Mineral Composition and Antioxidant Properties of Pigmented Rice

The effects of polishing on proximate compositions,physico-chemical characteristics,mineral compositions and antioxidant properties of the rice flours obtained from three different pigmented rice varieties(Chak-hao Angangba,Chak-hao Amubi and Chak-hao Poireiton) were investigated.The rice varieties were significantly(P 0.05) different in the contents of the test characteristics.Lipids,ash,minerals,phytochemicals(phenolic acids and flavonoids) and 2,2-diphenyl-1-picrylhydrazyl(DPPH) activity of rice flours were decreased after polishing(9% degree of milling),while amylose content and lightness were increased.X-ray diffraction pattern of rice flours exhibited A-type crystalline pattern with reflections at 15.1o,17.1o,18.2o and 23.0o.Pasting properties and transition temperatures were decreased after polishing treatment.Polishing resulted in changes in the crystallinity,enthalpy and morphology of rice flours.     

Differences in functional properties and biochemical characteristics of congenetic rice proteins

Proteins in brown rice (BR), white rice (WR) and rice bran (RB) were extracted from the same paddy rice and investigated for their components, functional properties and chemical characteristics by SDS-PAGE methodology. BR and WR proteins possessed a poor solubility under weak acid conditions due to a high content of glutenin and richness in higher molecular-weight (MW) protein fractions. Rice bran protein contained significantly lower molecular-weight components (MWs < 50 kDa) than those in WR and BR. Nitrogen solubility, foaming and emulsification properties of their rice protein preparations were affected not only by pH (3–11), but also by the concentrations of NaCl (0.4–2.0%) and sucrose (4.0–20.0%). All of them, particularly rice bran protein, had favorable functional properties in the medium with a high salt or sugar concentration. Therefore, they have a good potential for development in the food industry.     

原生态椰子油体外抗氧化活性

对原生态椰子油(VCO)的体外抗氧化活性进行了评价,分析了VCO中总酚酸的含量及其对DPPH自由基和ABTS+自由基的清除能力,对Fe~(2+)的络合能力以及对花生油的抗氧化能力.结果表明,VCO中总酚酸的含量为(0.180±0.003)mg/mL;对DPPH自由基的清除率为31.95%.低于Trolox、BHT和没食子酸;对ABTS~+自由基的清除能力为67.49 μmol/L Tmlox当量(TEAC值);对Fe~(2+)的络合能力优于Tmlox和BHT,但显著低于没食子酸;VCO对花生油具有一定的抗氧化能力.     

Isolation and antioxidative properties of phenolics-saponins rich fraction from defatted rice bran

The study presents a protocol for the preparation of phenolics-saponins rich fraction (PSRF), a new active nutraceutical from defatted rice bran followed by the determination of its antioxidant properties. PSRF was prepared by employing a simple alcoholic fractionation procedure on the crude alcoholic extract (CAE) of defatted rice bran. PSRF was found to be significantly higher in the contents of total phenolic, saponin, and steroidal saponin than CAE and its counterpart, aqueous fraction (AqF) (p < 0.05). Except for iron chelating activity, PSRF exhibited notably higher activity than CAE and AqF in all antioxidant activity assays performed (p < 0.05). HPLC-DAD analysis revealed that PSRF contained substantially higher amounts of gallic acid, 4-hydroxybenzoic acid, caffeic acid, p-coumaric acid, and ferulic acid than CAE and AqF (p < 0.05). In conclusion, alcoholic fractionation of CAE simultaneously concentrated the phenolic compounds and saponins into PSRF, thus contributed to its higher antioxidant activity. Due to its elevated antioxidant properties, PSRF may be recommended for investigation as an active ingredient in the nutraceutical, functional food, and natural food preservative formulations. This is also the first report suggesting defatted rice bran as a potential and sustainable source of saponins.