Evaluation of the effect of germination on phenolic compounds and antioxidant activities in sorghum varieties     

Dicko MH  Gruppen H  Traore AS  van Berkel WJ  Voragen AG 《Journal of agricultural and food chemistry》2005,53(7):2581-2588

The screening of 50 sorghum varieties showed that, on average, germination did not affect the content in total phenolic compounds but decreased the content of proanthocyanidins, 3-deoxyanthocyanidins, and flavan-4-ols. Independent of germination, there are intervarietal differences in antioxidant activities among sorghum varieties. Phenolic compounds and antioxidant activities were more positively correlated in ungerminated varieties than in germinated ones. Sorghum grains with pigmented testa layer, chestnut color glumes, and red plants had higher contents, larger diversity of phenolic compounds, and higher antioxidant activities than other sorghums. Some red sorghum varieties had higher antioxidant activities (30-80 mumol of Trolox equiv/g) than several sources of natural antioxidants from plant foods. Among varieties used for "to", "dolo", couscous, and porridge preparation, the "dolo"(local beer) varieties had the highest average content and diversity in phenolic compounds as well as the highest antioxidant activities. The biochemical markers determined are useful indicators for the selection of sorghum varieties for food and agronomic properties.  相似文献   

Conformational states of sunflower (Helianthus annuus) Helianthinin: effect of heat and pH     

González-Pérez S  Vereijken JM  Merck KB  van Koningsveld GA  Gruppen H  Voragen AG 《Journal of agricultural and food chemistry》2004,52(22):6770-6778

The structure and solubility of helianthinin, the most abundant protein of sunflower seeds, was investigated as a function of pH and temperature. Dissociation of the 11S form (hexamer) into the 7S form (trimer) gradually increased with increasing pH from 5.8 to 9.0. High ionic strength (I = 250 mM) stabilizes the 11S form at pH > 7.0. Heating and low pH resulted in dissociation into the monomeric constituents (2-3S). Next, the 7S and 11S forms of helianthinin were isolated and shown to differ in their secondary and tertiary structure, and to have denaturation temperatures (T(d)) of 65 and 90 degrees C, respectively. Furthermore, the existence of two populations of the monomeric form of helianthinin with denaturation temperatures of 65 and 90 degrees C was described. This leads to the hypothesis that helianthinin can adopt two different conformational states: one with T(d) = 65 degrees C and a second with T(d) = 90 degrees C.  相似文献   

Horseradish peroxidase-catalyzed cross-linking of feruloylated arabinoxylans with beta-casein   总被引：2，自引：0，他引：2  

Boeriu CG  Oudgenoeg G  Spekking WT  Berendsen LB  Vancon L  Boumans H  Gruppen H  van Berkel WJ  Laane C  Voragen AG 《Journal of agricultural and food chemistry》2004,52(21):6633-6639

Heterologous conjugates of wheat arabinoxylan and beta-casein were prepared via enzymatic cross-linking, using sequential addition of the arabinoxylan to a mixture of beta-casein, peroxidase, and hydrogen peroxide. The maximal formation of adducts between the beta-casein and the feruloylated arabinoxylan was reached at a protein-to-arabinoxylan ratio of 10:1, in combination with a molar ratio hydrogen peroxide to substrate of 2:1 and a molar protein-to-enzyme ratio between 10(2) and 10(4). The protein-arabinoxylan adducts were separated from the arabinoxylan homopolymers by size exclusion and anion exchange chromatography. The molar ratio protein:arabinoxylan in the purified conjugates varied between 0.1 and 5.6. This is the first report on the large-scale enzymatic preparation of heterologous protein-arabinoxylan conjugates.  相似文献   

Tentative assignment of the potato serine protease inhibitor group as beta-II proteins based on their spectroscopic characteristics     

Pouvreau L  Gruppen H  van Koningsveld GA  van den Broek LA  Voragen AG 《Journal of agricultural and food chemistry》2004,52(25):7704-7710

Potato serine protease inhibitor (PSPI) is the most abundant protease inhibitor group in potato tuber. The investigated PSPI isoforms have a highly similar structure at both the secondary and the tertiary level. From the results described, PSPI is classified as a beta-II protein based on (1) the presence in the near-UV spectra of sharp peaks, indicating a rigid and compact protein; (2) the sharp transition from the native to the unfolded state upon heating (only 6 degrees C) monitored by a circular dichroism signal at 222 nm; and (3) the similarity in secondary structure to soybean trypsin inhibitor, a known beta-II protein, as indicated by a similar far-UV CD spectrum and a similar amide I band in the IR spectrum. The conformation of PSPI was shown also to be stable at ambient temperature in the pH range 4-7.5. Upon lowering the pH to 3.0, some minor changes in the protein core occur, as observed from the increase of the intensity of the phenylalanine peak in the near-UV CD spectrum.  相似文献   

Comparison of content in phenolic compounds,polyphenol oxidase,and peroxidase in grains of fifty sorghum varieties from burkina faso     

Dicko MH  Hilhorst R  Gruppen H  Traore AS  Laane C  van Berkel WJ  Voragen AG 《Journal of agricultural and food chemistry》2002,50(13):3780-3788

Analysis of fifty sorghum [Sorghum bicolor (L.) Moench] varieties used in Burkina Faso showed that they have different contents of phenolic compounds, peroxidase (POX), and polyphenol oxidase (PPO). Most of the varieties (82%) had a tannin content less than 0.25% (w/w). POX specific activity was higher than the monophenolase and o-diphenolase specific activities of PPO. For POX, there was a diversity of isoforms among varieties. No clear correlation could be made between the quantitative composition of the grain in phenolics, PPO, and POX, and resistance of plant to pathogens. In general, varieties good for a thick porridge preparation ("t?") had low phenolic compounds content and a medium POX activity. From the red varieties, those used for local beer ("dolo") had a high content in phenolic compounds and PPO, and a low POX activity. The variety considered good for couscous had a low POX content. The characteristics might be useful as selection markers for breeding for specific applications.  相似文献   

Emission Inventories for SO2 and NOx in Developing Country Regions in 1995 with Projected Emissions for 2025 According to Two Scenarios     

Vallack  Harry W.  Cinderby  Steve  Kuylenstierna  Johan C.I.  Heaps  Charles 《Water, air, and soil pollution》2001,130(1-4):217-222

Water, Air, &; Soil Pollution - Top-down inventories of anthropogenic SO2 and NOx emissions were compiled for 1995 for developing country regions. Regional emission factors were used to generate...  相似文献   

Der Gehalt einiger Purin- und Pyrimidin-Verbindungen und Nukleinsäuren in Blättern von Gerste-Pflanzen verschiedener Sorten in Abhängigkeit vom Alter der Pflanzen     

Harry Bergmann 《Genetic Resources and Crop Evolution》1972,20(1):327-349

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Veterinary Clinical Parasitology, 6th ed          下载免费PDF全文

Harry Smith 《The Canadian veterinary journal. La revue veterinaire canadienne》1995,36(2):118-119

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The intestinal flora of the chicken in the period 2 to 6 weeks of age, with particular reference to the anaerobic bacteria   总被引：15，自引：0，他引：15  

E M Barnes  G C Mead  D A Barnum  E G Harry 《British poultry science》1972,13(3):311-326

A study has been made of the intestinal flora of chickens aged between 2 and 6½ weeks. No major differences were found when rations containing 9 or 25% fish meal were compared or when two different sources of fish meal were used. Throughout the period investigated, it was confirmed that the lactobacilli are the only group of organisms generally present in the small intestine in numbers exceeding 104/g. Clostridia were regularly found at 102 to 104/g, but Clostridium welchii was isolated from only occasional samples.

In the caeca, the total number of bacteria present at 2, 3, 4 and 6½ weeks was about 1011/g. Of these it was generally possible to isolate more than 20% using an anaerobic roll‐tube technique and oxygen‐free CO2. Many different types of anaerobes were isolated including strictly anaerobic budding bacteria which had not previously been studied. During the growth of the bird the flora changed. Anaerobic streptococci (peptostreptococci) predominated at 2 weeks but gradually decreased so that by 6½ weeks these organisms formed only a small part of the flora. Many of the Gram‐negative non‐sporing anaerobes only appeared between the 4th and 6th weeks.

Throughout the 2 to 6½‐week period all the caecal samples examined contained 108 to 109 anaerobes/g which were able to attack uric acid and sometimes 1010/g. This property was shared by at least one group of peptostreptococci, four groups of Gram‐negative non‐sporing anaerobes, three groups of Gram‐variable or Gram‐positive anaerobic non‐sporing rods and several species of clostridia.  相似文献   

Physiologic responses of feral horses to succinylcholine chloride immobilization     

LeRoy V. Gallagher DVM  MS  Ronald E. Borchard DVM  PhD  Paul A. Klavano DVM  Harry W. Vaughn DVM 《Journal of Equine Veterinary Science》1983,3(2):48-52

Five captive feral horses were immobilized at 72 hour intervals for 30 days by intramuscular administration of succinylcholine chloride (SCh) using a capture gun and dart system. The serum enzyme activities of creatine phosphokinase, glutamate-oxaloacetate transaminase, and lactate dehydrogenase and serum cortisol concentrations were monitored to assess the response to chemical immobilization in feral horses over time.Reference values for these parameters in feral horses were found to be in close agreement with those of normal, rested horses not in training. The results suggest that single, or infrequently repeated, use of succinylcholine-chloride by intramuscular administration to captive feral horses, or to otherwise unapproachable horses, could be efficiently and practically employed in field situations without major physiologic alterations and with minimal stress occurring in these horses.  相似文献