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1.
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.  相似文献   

2.
The objectives of this study were to (1) investigate the relationship between physicochemical characteristics (mean/median particle sizes, physical hull content) and hydrolyzed hydroxycinnamic acid profile (ferulic acid (FA), para-coumaric acid (pCA), and their ratio) of barley varieties and in situ rumen degradability in dairy cattle; and (2) investigate rumen degradation kinetics of FA and pCA of CDC barley varieties grown in western Canada. Barley variety had a significant effect (P < 0.05) on rumen undegradable fraction of DM, FA, pCA, neutral (NDF) and acid detergent fiber (ADF) at 12 and/or 24 h of rumen incubation. FA in barley grain was more degradable than the pCA (P < 0.05). There were no differences (P > 0.05) in effective degradability of DM (EDDM) and EDFA, but significant differences in EDpCA (P < 0.05). Barley hull was strongly correlated to NDF, ADF, ADL, hemicellulose and cellulose (R > 0.78, P < 0.001) and correlated to FA (R = 0.57, P < 0.05) but not to pCA (R = 0.42, P > 0.05) in original samples. FA and pCA were highly and positively correlated to NDF, ADF, ADL, hemicellulose, cellulose, mean/median particle sizes, and rumen indigestible DM, NDF and ADF at either 12 or 24 h (P < 0.05). Mean/median particle size of barley grain positively influenced the rumen indigestible DM, but not others (FA, pCA). The results implied that reduction of barley hull, FA and pCA contents could increase the degradability of barley grain in rumen. Multi-regression with best model variable selection analysis revealed that FA was the factor most inhibiting to DM degradability of barley in rumen, and was the most effective factor to predict DM degradability, while hull was the most effective factor to determine NDF degradability in rumen. Both hull and FA affected ADF degradability in the rumen. The results indicate that breeding or identifying barley varieties with lower hull and FA contents would result in higher degradability, higher energy density and higher quality barley and improve nutrient availability of barley.  相似文献   

3.
An analytical ultrasound-assisted extraction (UAE) technique has been optimized and validated for the extraction of tryptophan and its derivatives from rice grains. A Box–Behnken design in conjunction with a response surface methodology based on six factors and three levels was used to evaluate the effects of the studied factors prior to optimizing the UAE conditions. The significant (p < 0.05) response surface models with high coefficients of determination were fitted to the experimental data. The most significant (p < 0.0001) effect is the solvent-to-sample ratio while quadratic effects caused by temperature and solvent-to-sample ratio were of moderate importance (p < 0.05). The optimal UAE conditions were as follows: extraction time of 5 min, ultrasound amplitude of 30%, cycle of 0.7 s−1, extraction temperature of 30 °C, 8% methanol in water as the extraction solvent at pH 3 and a solvent/solid ratio 5:1. The method validation ensured that appropriate values were obtained for the LOD, LOQ, precision and recovery. Furthermore, the method was successfully applied to the analysis of a number of rice samples of different varieties. It was demonstrated that this particular UAE method is an interesting tool for the determination of tryptophan and tryptophan derivatives in rice grain samples.  相似文献   

4.
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5.
In this work, α-amylase was used to treat oat flour with the intent to release phenolic compounds with known antioxidant properties. After methanol extraction, the amounts of nine beneficial phenolic compounds were measured using HPLC. The antioxidant activities of the extracts were assessed using 2,2′-azinobis (3- ethylbenzothiazoline-6-sulfonic acid) (ABTS)，2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and protein oxidative damage protection assays. Compared with heating-only treated oat flour, that treated with α-amylase showed significant increase of extractable total phenolic content (0.46–1.35 μmol gallic acid equivalents per gram oat), total antioxidant capacity, and an increased ability on the protection of protein from oxidative damage. Heating-only increased caffeic acid and vanillin content by 17 (0.03 vs 0.54 μg/g oat) and 1.8 (0.62 vs 1.11 μg/g oat) folds, but slightly increased the content of other phenols. Excluding heating effect, α-amylase treatment increased gallic acid content by 2.6 folds (0.38 vs 1.38 μg/g oat), caffeic acid content by 2.4 (0.54 vs 1.82 μg/g oat) folds, and other phenols by 1.0–1.8 folds. In conclusion, α-amylase treatment can yield oat products containing more extractable phenolic compounds with increased antioxidant capacity.  相似文献   

6.
The outstanding high carotenoid content of the tritordeum (×Tritordeum Ascherson et Graebner) grains, a promising novel cereal derived from the crossing of durum wheat and the wild barley Hordeum chilense, has previously been assigned as a character derived from the genetic background of its wild parent. The carotenoid profile of H. chilense, especially the lutein esters presented in this study, provide biochemical evidences to confirm this affirmation, being the first time that the individual carotenoid profile of this cereal has been characterized. The total carotenoid content (6.14 ± 0.12 μg/g) and the individual carotenoid composition were very similar to the tritordeum grains, with lutein being the major carotenoid (88%; 5.38 ± 0.11 μg/g) and very low levels of β-carotene. In contrast to tritordeum, H. chilense presented a considerable amount of zeaxanthin (12%; 0.74 ± 0.01 μg/g). Up to 55% of lutein was esterified with palmitic (C16:0) and linoleic (C18:2) acids, presenting a characteristic acylation pattern, in agreement with the tritordeum one, and composed by four monoesters (lutein 3′-O-linoleate, lutein 3-O-linoleate, lutein 3′-O-palmitate and lutein 3-O-palmitate) and four diesters (lutein dilinoleate, lutein 3′-O-linoleate-3-O-palmitate, lutein 3′-O-palmitate-3-O-linoleate, lutein dipalmitate). These data may be useful in the field of carotenoid biofortification of cereals.  相似文献   

7.
Tracking changes in the bioactive compounds of white (ML-W), red (ML-R) and black (RB) rice during the 5 stages of grain development were studied. Total anthocyanin (TAC) was found only in RB (stages 3–5) and proanthocyanidin (TPAC) contents were only found in ML-R (stages 2–5). Considerable amounts of total phenolic contents (TPC) were found in stages 2–4 of ML-R, while total flavonoid contents (TFC) were most detected in stages 4–5 of RB. The DPPH activity of ML-W and ML-R decreased from stages 1–5. The highest FRAP activity was found in ML-R (stages 2–3) indicating that it is highly related to the bioactive compound content. Cyanidin-3-glucoside and peonidin-3-glucoside were found in RB at stages 3–5. The cyanidin of RB in stages 4–5 was related to the amount of TAC. The proanthocyanidin compound catechin was first found and reported in stages 2–3 of ML-R. Principal component analysis indicated that antioxidant activity and the bioactive components were highly related. The data from this study suggests that ML-R at stage 2 and RB at stage 4 are the most suitable stages for harvesting to achieve the highest level of bioactive compounds, which have many health benefits.  相似文献   

8.
Digestibility of fiber components namely neutral detergent fiber (total content of cellwall) cellulose, hemicellulose and lignin are estimated in 14 healthy vegetarian men during adlibitum feeding and at 3 energy levels namely 2526, 2868 and 3290 kcals/day. Values of digestibility for adlibitum experiments were 34.17±2.3 for neutral detergent fiber (NDF), 30.1±3.9 for cellulose and 53.4±3.0 for hemicellulose and 8.1±2.6 for lignin. There was a considerable variability in digestibility of fiber components between individuals.  相似文献   

9.
Improvement of the nutritive value of dual-purpose sorghum (Sorghum bicolor (L.) Moench) stover is an important objective for the semi-arid tropics where sorghum crop residue is extensively used for livestock feed. To identify the relative importance of genetic and environmental sources of variation for nutritive value, leaves and stems of six diverse dual-purpose sorghum cultivars were evaluated for in vitro gas production (Gas48hr), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin, nitrogen, and ash contents under two fertility and two plant-density regimes during 2 years in India. Substantial genotypic differences were observed for stem Gas48hr (25.7 to 33.0 ml in 200 g−1 dry matter (DM)) and NDF (564–687) content. Gas48hr and NDF content of stems exhibited more promise as selection criteria than those of leaves, as stems showed larger portion of variation attributed to genotypes, relatively less genotype by environment (GE) interactions, and were closely related to whole-plant values. Year, nitrogen fertilization and plant density showed very little influence on Gas48hr, NDF or ADF of leaves and stems. Gas48hr exhibited substantial GE interactions with all environmental factors, indicating the need for multi-environment testing to achieve progress.  相似文献   

10.
This study evaluated the effects of a ferulic acid esterase (FAE) and a non‐FAE‐producing inoculant applied alone or in combination with exogenous fibrolytic enzymes (EFE) on the fermentation and nutritive value of mixed grain (barley, oats and spring triticale) silage. The mixed crop was ensiled in laboratory mini‐silos either untreated (CON), or treated with a FAE inoculant (FAE), a non‐FAE inoculant (NFAE) or NFAE + EFE. Inoculated silages were lower (P < 0·01) in water‐soluble carbohydrate, whereas NFAE and NFAE + EFE silages had higher (P < 0·001) DM loss than other silages. FAE and NFAE silage had higher neutral detergent fibre (NDF), but were lower in NFAE + EFE than other silages (P < 0·001). Copy numbers of 16S rRNA associated with Lactobacillus buchneri were higher (P < 0·001) in NFAE and NFAE + EFE silages than in others, resulting in higher (P < 0·001) acetic acid in these silages. NFAE + EFE silage had lower (P < 0·001) in vitro gas production and NDF digestibility (NDFD) than other silages. FAE silage had higher (P < 0·01) in situNDFD than CON and NFAE + EFE silages. Inoculation of mixed small‐grain silage with NFAE‐producing inoculants combining EFE reduced NDFD.  相似文献   

11.
The quality of common wheat is largely influenced by the composition of its storage proteins. The currently presented research explores factors influencing observed differences in quality and quantity between wheat cultivars, in particular in relation to gluten composition and its relationship to technological characteristics. Eight wheat cultivars (H. Wieser, Seilmeier, W., Belitz, H.D., 1994 Parsi, Sirvan, Sivand, Pishgam, Pishtaz)were selected for evaluation. Analysis results demonstrated that Morvarid and Sirvan cultivars yielded the highest quality of wheat, while the Chamran cultivar was indicated as the most favorable for baking Taftoon bread. Conversely, the Sepahan cultivar was deemed to have the worse quality in both categories. A Q Exactive LC-MS/MS system was employed to evaluate the most effective sub-fractions of gliadin and glutenin on wheat quality. Matching peptides resulting from trypsin digestion on gliadin and glutenin fractions, led to the identification of subunits α/β-gliadin, γ-gliadin, HMW-Dx5, HMW-Bx17, HMW-Dy3, HMW-Dy10, HMW-By15, LMW-m, LMW-s, and LMW-i. The obtained results indicated that the most influential subunits of glutenin on wheat quality were Dy10, Dy3 and Dx5, while the most effective gliadin subfraction was noted to be α/β-gliadin However, the most important subunit influencing the quality of flat breads in particular was identified as the x-HMW-GS, in particular the Bx17 subunit, and LMW-GS.  相似文献   

12.
This study evaluated the effect of two fibrolytic enzyme products, applied at baling, on the chemical composition and digestibility of alfalfa hay. Three replicate bales of alfalfa hay (82% dry matter) were produced with the application of one of five treatments including an untreated control and one of two fibrolytic enzyme products (DYC and ECO), either applied alone or in combination with a ferulic acid esterase‐producing bacterial additive. The enzyme products were applied on the basis of endoglucanase activity. The neutral detergent fibre (NDF) concentration and accumulated temperature after storage of hay produced using DYC‐ or ECO‐based treatments were greater (P < 0·05) than untreated hay, except for hay bales produced using ECO alone. Bales produced using ECO‐based treatments had a greater (P < 0·05) in vitro NDF digestibility compared with untreated bales. The application of fibrolytic enzymes at baling may potentially improve NDF digestibility without negatively affecting chemical composition or increasing aerobic deterioration. However, the effects of fibrolytic enzymes varied depending on the product applied. Combining ferulic acid esterase‐producing bacterial additives with fibrolytic enzymes did not improve the nutritive value of hay after storage.  相似文献   

13.
Brewers' spent grain (BSG) is the insoluble residue generated from the production of wort in the brewing industry. This plant-derived by-product is known to contain significant amounts of valuable components, which remain unexploited in the brewing processes. Therefore, it is essential to develop a more detailed characterization of BSG in order to highlight its potential in developing new value-added products and simultaneously solve the environmental problems related to its discharge. The content of BSG in several biologically active compounds (fatty acids, polyphenols, flavonoids, antioxidant capacity) as well as its volatile fingerprint were assessed and compared with the composition of barley, malt and wheat flour samples. The obtained results emphasized the importance and the opportunities of the re-use of this agro-industrial by-product.  相似文献   

14.
The process of in vivo esterification of xanthophylls has proven to be an important part of the post-carotenogenesis metabolism which mediates their accumulation in plants. The biochemical characterization of this process is therefore necessary for obtaining new and improved crop varieties with higher carotenoid contents. This study investigates the impact of postharvest storage conditions on carotenoid composition, with special attention to the esterified pigments (monoesters, diesters and their regioisomers), in durum wheat and tritordeum, a novel cereal with remarkable carotenoid content. For tritordeum grains, the total carotenoid content decreased during the storage period in a clear temperature-dependent manner. On the contrary, carotenoid metabolism in durum wheat was very much dependent on the physiological adaptation of the grains to the imposed conditions. Interestingly, when thermal conditions were more intense (37 °C), a higher carotenoid retention was observed for tritordeum, and was directly related to the de novo esterification of the lutein induced by temperature. The profile of lutein monoester regioisomers was constant during storage, indicating that the regioisomeric selectivity of the XAT enzymes was not altered by temperature. These data can be useful for optimizing the storage conditions of grains favoring a greater contribution of carotenoids from these staple foods.  相似文献   

15.
Consumption of whole-wheat based products is encouraged due to their important nutritional elements that benefit human health. However, the use of whole-wheat flour is limited because of the poor processing and end-product quality. Bran was postulated as the major problem in whole wheat breadmaking. In this study, four major bran components including lipids, extractable phenolics (EP), hydrolysable phenolics (HP), and fiber were evaluated for their specific functionality in flour, dough and bread baking. The experiment was done by reconstitution approach using the 24 factorial experimental layout. Fiber was identified as a main component to have highly significant (P < 0.05) and negative influence on most breadmaking characteristics. Although HP had positive effect on farinograph stability, it was identified as another main factor that negatively impacted the oven spring and bread loaf volume. Bran oil and EP seemed to be detrimental to most breadmaking characteristics. Overall, statistical analysis indicates that influence of the four bran components are highly complex. The bran components demonstrate multi-way interactions in regards to their influence on dough and bread-making characteristics. Particularly, Fiber appeared to have a high degree of interaction with other bran components and notably influenced the functionality of those components in whole wheat bread-making.  相似文献   

16.
To enlarge the feed resources and enhance the utilization efficiency of straws as ruminant feed in Tibet, four kinds of local crop straws with tall fescue (Festuca arundinacea Schreb.) based on the ratio of 40/60 (fresh weight) were ensiled with four levels (0, 10%, 20% and 30% of fresh weight) of alfalfa (Medicago sativa L.), respectively. The laboratory silos (1L) were opened after 45 days of ensiling, and the fermentation characteristics, nutritive value and in vitro digestibility of the mixed silages were analysed. The silages including alfalfa had significantly (p < 0.05) or numerically (p > 0.05) higher lactic acid and crude protein contents, lactic acid bacteria counts, in vitro digestibility of dry matter, neutral detergent fibre (NDF) and acid detergent fibre (ADF), and lower NDF and ADF contents than controls. The results suggest that inclusion of alfalfa to mixtures of straws and tall fescue had favourable effects on fermentation quality and obviously improved the nutritive value and in vitro digestibility of mixed silages. This effect was most evident when the inclusion proportion of alfalfa was 30% in oat straw mixed silage.  相似文献   

17.
为了探究酶制剂对苎麻混合青贮品质的影响,本试验在苎麻与麦麸(80%苎麻+18%麦麸+2%蔗糖)混合青贮中分别添加10 mL蒸馏水(对照组)、纤维素酶2 g/kg、纤维素酶2 g/kg+半纤维素酶0.4 g/kg、纤维素酶2 g/kg+半纤维素酶0.4 g/kg+果胶酶0.7 g/kg,30天后开包取样分析各项指标。结果表明,苎麻与麦麸混合青贮发酵品质和营养品质均较好。与对照相比,添加酶制剂显著提高了碳水化合物、干物质和粗蛋白含量(P<0.05),显著降低了中性洗涤纤维、酸性洗涤纤维、粗纤维的含量和氨态氮/总氮比值(P<0.05),但是对pH值、乳酸、乙酸和丙酸含量无显著影响(P<0.05)。本试验条件下,添加酶制剂能够有效提高苎麻混合青贮的品质,单独添加纤维素酶与复合酶制剂无显著性差异,从节约成本角度考虑,单独添加纤维素酶组为最佳选择。  相似文献   

18.
We aimed to evaluate the effects of chitosan and microbial inoculant addition to sugarcane silage fermentation, gas and effluent losses, chemical composition, in situ dry matter (DM), neutral detergent fibre (NDF) degradation and aerobic stability. A completely randomized design with four treatments (n = 40) was performed. It was arranged in a 2 × 2 factorial scheme with chitosan [0 and 6 g/kg of sugarcane DM—1.66 g/kg of natural matter (NM)] and microbial inoculant (0 and 8 mg/kg on NM). Each g of inoculant contained 3.9 × 1010 UFC/g of Pediococcus acidilactici and 3.75 × 1010 UFC/g of Propionibacterium acidicipropionici. The addition of microbial inoculant increased lactic acid concentration in silos treated with chitosan. Furthermore, chitosan increased pH and tended to increase acetic acid of silage. In contrast, the inoculant decreased pH and acetic acid, besides increasing ethanol concentration. As chitosan addition increased DM recovery, inoculant addition decreased it. Chitosan decreased NDF and acid detergent fibre (ADF) level and increased DM degradation, while inoculant decreased DM content, DM and NDF degradation. In addition, chitosan improved the aerobic stability only in non‐inoculated silos. Thus, chitosan has a positive effect on silage fermentation, reducing fermentative losses, and improving silage chemical composition and degradation. Conversely, the addition of microbial inoculant negatively affected silage DM recovery, chemical composition, and its association with chitosan decreased the aerobic stability when compared to the exclusive use of chitosan.  相似文献   

19.
Raw rice bran was treated with or without visible light exposure at room temperature or stored at 40 °C in the dark for 10 days and rice bran oil (RBO) was recovered from each rice bran. Headspace oxygen content from rice bran and conjugated dienoic acid (CDA) value, acid value, content of γ-oryzanol, and fluorescence intensity in RBO were analyzed to determine the effects of visible light on the oxidative stability in rice bran. Headspace oxygen content in visible light irradiated rice bran (RBL) decreased by 12.8% for 10 days while those in the dark (RBD) and stored at 40 °C (RBT) decreased by 5.87 and 5.35%, respectively, implying visible light irradiation accelerates the consumption of oxygen. CDA values in RBO from RBL were significantly higher than those in RBO from RBD and RBT (p < 0.05). However, acid values in RBO were not significantly different among samples (p > 0.05). Both γ-oryzanol content and fluorescence intensity in RBO from RBL were significantly lower than those in RBO from RBD and RBT (p < 0.05). Fluorescence intensity, which is related to the content of chlorophylls, decreased in samples under light only, implying that chlorophyll photosensitization may play important roles in the acceleration of lipid oxidation in rice bran.  相似文献   

20.
The nutritive value of pasture is an important determinant of the performance of grazing livestock. Proximal sensing of in situ pasture is a potential technique for rapid prediction of nutritive value. In this study, multispectral radiometry was used to obtain pasture spectral reflectance during different seasons (autumn, spring and summer) in 2009–2010 from commercial farms throughout New Zealand. The analytical data set (n = 420) was analysed to develop season‐specific and combined models for predicting pasture nutritive‐value parameters. The predicted parameters included crude protein (CP), acid detergent fibre (ADF), neutral detergent fibre (NDF), ash, lignin, lipid, metabolizable energy (ME) and organic matter digestibility (OMD) using a partial least squares regression analysis. The calibration models were tested by internal and external validation. The results suggested that the global models can predict the pasture nutritive value parameters (CP, ADF, NDF, lignin, ME and OMD) with moderate accuracy (0·64 ≤ r2 ≤ 0·70) while ash and lipid are poorly predicted (0·33 ≤ r2 ≤ 0·40). However, the season‐specific models improved the prediction accuracy, in autumn (0·73 ≤ r2 ≤ 0·83) for CP, ADF, NDF and lignin; in spring (0·61 ≤ r2 ≤ 0·78) for CP and ash; in summer (0·77 ≤ r2 ≤ 0·80) for CP and ash, indicating a seasonal impact on spectral response.  相似文献   

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