Electron spin resonance (ESR) studies on the formation of roasting-induced antioxidative structures in coffee brews at different degrees of roast     

Bekedam EK  Schols HA  Cämmerer B  Kroh LW  van Boekel MA  Smit G 《Journal of agricultural and food chemistry》2008,56(12):4597-4604

The antioxidative properties of coffee brew fractions were studied using electron spin resonance spectroscopy using 2,2,6,6-tetramethyl-1-piperidin-1-oxyl (TEMPO) and Fremy's salt (nitrosodisulfonate) as stabilized radicals. TEMPO was scavenged by antioxidants formed during roasting and not by chlorogenic acid, whereas Fremy's salt was scavenged by all antioxidants tested including chlorogenic acid. The stabilized radical TEMPO allowed the exclusive measurement of roasting-induced antioxidants. The roasting-induced antioxidant activity of coffee brews increased with increasing degree of roast, and most of these antioxidants were formed during the initial roasting stage. The majority of these roasting-induced antioxidants were present in the high molecular weight fractions, indicating that the formation of these antioxidants preferably occurs at specific high molecular weight structures, likely being arabinogalactan and/or protein moieties which might be part of the melanoidin complex. It was found that chlorogenic acids most probably do not lose their antioxidant activity and phenolic characteristics upon incorporation in coffee melanoidins. The parameter fast reacting antioxidants (FRA) was introduced as an alternative for the antioxidative potential. FRA levels showed that coffee fractions rich in roasting-induced antioxidants exposed their antioxidant activity relatively slowly, which must be a consequence of its complex structure. Finally, the melanoidin content and the roasting-induced antioxidant activity showed a positive and linear correlation for the coffee brew fractions, showing that roasting-induced antioxidants are present within melanoidins. This is the first time that the formation of roasting-induced antioxidants could be directly correlated with the extent of Maillard reaction and melanoidin formation in a complex product such as coffee.  相似文献   

Serum alpha1‐proteinase inhibitor concentrations in dogs with systemic inflammatory response syndrome or sepsis          下载免费PDF全文

Romy M. Heilmann Dr med vet  PhD  DACVIM  DECVIM  Niels Grützner Dr med vet  PhD  Brittany E. Thames DVM  MPH  Jörg M. Steiner Dr med vet  PhD  DACVIM  DECVIM  James W. Barr DVM  DACVECC 《Journal of Veterinary Emergency and Critical Care》2017,27(6):674-683

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Fecal markers of inflammation,protein loss,and microbial changes in dogs with the acute hemorrhagic diarrhea syndrome (AHDS)          下载免费PDF全文

Romy M. Heilmann DVM  DACVIM  DECVIM  PhD  Melissa M. Guard MSc  DVM  Jörg M. Steiner DVM  DACVIM  PhD  Jan S. Suchodolski DVM  PhD  Stefan Unterer DVM  DECVIM 《Journal of Veterinary Emergency and Critical Care》2017,27(5):586-589

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Untersuchungen zum notwendigen Maß bei der Anwendung von Pflanzenschutzmitteln in Winterweizen in den Jahren 2004 bis 2016     

Jürgen Schwarz  Bettina Klocke  Christina Wagner  Sandra Krengel 《Gesunde Pflanzen》2018,70(3):119-127

In order to provide recommendations for future cropping systems with regard to the necessary minimum of pesticide use, a long-term field trial at the field site in Dahnsdorf of the Julius Kühn-Institute was conducted in the years 2004 to 2016 to investigate possible reduction of pesticides, taking into account the general principles of integrated pest management (Strategies to reduce the use of plant protection products). Two winter wheats (WW1 and WW2) were part of the crop rotation with six components and different quality classes (A wheat (WW1) and E wheat (WW2)) and resistance levels to important wheat pathogens. In all years, herbicides and fungicides were needed to control weeds and fungal pathogens due to the excess of the control threshold. Insecticides were only necessary in two years. When considering the treatment frequency index (TFI), the mean overall TFI varied with 2.6 in WW1 and 3.5 in WW2, but was significantly lower compared to practice. There were also differences in the mean fungicide TFI of the two crop rotation elements with 1.1 in WW1 and 1.6 in WW2 due to their different resistance level to important fungal pathogens. The same is true with regard to the herbicide TFI with of 1.1 in WW1 and 1.3 in WW2. The treatments in the strategies 2, 3 and 4 mostly resulted in significantly higher yields compared to the non-chemical strategy 1, which can be attributed to the strong weed and fungal infestations in strategy 1 and the good efficacy of the used plant protection products. The tended differences between strategy 2 with a situation-related application rate and the 25 and 50% reduced application rates in strategies 3 and 4, respectively, were not significant. A reduced application rate showed no negative long-term effects on weed emergence even after 13 years, but increased emergence numbers in strategies with reduced herbicide use. The results show that plant protection products savings are possible without significantly reducing yields. However, this requires a high level of human resources for monitoring and scoring the consistent observance of the principles of integrated pest management, such as the consideration of good crop rotation, the cultivation of resistant cultivars and the optimally coordinated treatments after the control threshold has been exceeded.  相似文献