Different polyphenolic components of soft fruits inhibit alpha-amylase and alpha-glucosidase

Polyphenol-rich extracts from soft fruits were tested for their ability to inhibit alpha-amylase and alpha-glucosidase. All extracts tested caused some inhibition of alpha-amylase, but there was a 10-fold difference between the least and most effective extracts. Strawberry and raspberry extracts were more effective alpha-amylase inhibitors than blueberry, blackcurrant, or red cabbage. Conversely, alpha-glucosidase was more readily inhibited by blueberry and blackcurrant extracts. The extent of inhibition of alpha-glucosidase was related to their anthocyanin content. For example, blueberry and blackcurrant extracts, which have the highest anthocyanin content, were the most effective inhibitors of alpha-glucosidase. The extracts most effective in inhibiting alpha-amylase (strawberry and raspberry) contain appreciable amounts of soluble tannins. Other tannin-rich extracts (red grape, red wine, and green tea) were also effective inhibitors of alpha-amylase. Indeed, removing tannins from strawberry extracts with gelatin also removed inhibition. Fractionation of raspberry extracts on Sephadex LH-20 produced an unbound fraction enriched in anthocyanins and a bound fraction enriched in tannin-like polyphenols. The unbound anthocyanin-enriched fraction was more effective against alpha-glucosidase than the original extract, whereas the alpha-amylase inhibitors were concentrated in the bound fraction. The LH-20 bound sample was separated by preparative HPLC, and fractions were assayed for inhibition of alpha-amylase. The inhibitory components were identified as ellagitannins using LC-MS-MS. This study suggests that different polyphenolic components of fruits may influence different steps in starch digestion in a synergistic manner.     

A major QTL for gluten strength in durum wheat (Triticum turgidum L. var. durum)

Gluten strength is an important characteristic, determining the end product quality of durum wheat semolina. To identify the genetic basis of gluten strength in North Dakota durum cultivars, a doubled haploid population was developed from the cross of a weak gluten cultivar ‘Rugby’ and a strong gluten cultivar ‘Maier’. A framework linkage map consisting of 228 markers was constructed and used with phenotypic data on gluten strength (measured by sedimentation volume) to conduct single- and two-locus QTL analyses. Only one consistent QTL (QGs.ndsu-1B) contributing up to 90% of the phenotypic or 93% of the genotypic variation was detected on 1BS. No QTL × QTL or QTL × environment interactions were observed. The QGs.ndsu-1B was flanked by two DArT markers which were converted to STS markers and used along with SSR and EST-SSRs to develop a map of 1BS. QTL analysis delineated QGs.ndsu-1B in a 7.3 cM region flanked by an STS marker (STS-wPt2395) and a SSR marker (wmc85). The adapted background of this material and availability of PCR-based markers closely associated with this locus represent invaluable resources for marker-assisted introgression of gluten strength into other durum wheat varieties. A single QTL segregating in this population also makes it an ideal target for map-based cloning.     

A simple treatment for “rye-grass staggers”?

Abstract

Extract

Sir,—A series of happy coincidences (serendipity?) has led us to a simple treatment which seems to have successfully alleviated symptoms of “rye-grass staggers” in a horse, a calf and two badly affected sheep. Although primarily engaged in a search for the causative agent(s) of rye-grass staggers, casual conversations with people having long experience of this disorder revealed many interesting observations. One of these was a racing-stable remedy for rye-grass staggers, which was the administration of “a couple of handfulls” of Epsom salts in a bran mash, with as much puha (Sonchus oleraceus) as the horse would eat. A suggestion that puha may be high in potassium led to the substitution of potassium chloride for puha, and on 9 March 1981, a thoroughbred mare was dosed with 100 g MgS0₄7H₂O and 6g KCl. This animal had marked symptoms of ryegrass staggers, such as swaying and head-weaving when standing, and a very irregular and unsteady gait at the walk. It is doubtful whether the animal could have trotted in this condition. The mare was greatly improved the following day, with no evidence of the above symptoms, and on the 13 March, the mare was able to trot freely around her paddock when chased by a motor bike. On the 16 March the mare again showed symptoms of rye-grass staggers, was treated as before and similarly improved. On 13 March a calf was reported to be staggering, and was drenched with 50 g MgSO₄7H₂O and 3 g K? 1. It too, recovered, and on 20 March showed only very slight symptoms, which had not worsened by 23 March and further treatment was not warranted.     

Qualitative and quantitative control of carbonated cola beverages using ¹H NMR spectroscopy

1H Nuclear magnetic resonance (NMR) spectroscopy (400 MHz) was used in the context of food surveillance to develop a reliable analytical tool to differentiate brands of cola beverages and to quantify selected constituents of the soft drinks. The preparation of the samples required only degassing and addition of 0.1% of TSP in D?O for locking and referencing followed by adjustment of pH to 4.5. The NMR spectra obtained can be considered as "fingerprints" and were analyzed by principal component analysis (PCA). Clusters from colas of the same brand were observed, and significant differences between premium and discount brands were found. The quantification of caffeine, acesulfame-K, aspartame, cyclamate, benzoate, hydroxymethylfurfural (HMF), sulfite ammonia caramel (E 150D), and vanillin was simultaneously possible using external calibration curves and applying TSP as internal standard. Limits of detection for caffeine, aspartame, acesulfame-K, and benzoate were 1.7, 3.5, 0.8, and 1.0 mg/L, respectively. Hence, NMR spectroscopy combined with chemometrics is an efficient tool for simultaneous identification of soft drinks and quantification of selected constituents.     

Chronic Pancreatitis in Dogs

Chronic pancreatitis used to be considered uncommon in dogs, but recent pathological and clinical studies have confirmed that it is in fact a common and clinically significant disease. Clinical signs can vary from low-grade recurrent gastrointestinal signs to acute exacerbations that are indistinguishable from classical acute pancreatitis. Chronic pancreatitis is a significant cause of chronic pain in dogs, which must not be underestimated. It also results in progressive impairment of endocrine and exocrine function and the eventual development of diabetes mellitus or exocrine pancreatic insufficiency or both in some affected dogs at end stage. The etiology is unknown in most cases. Chronic pancreatitis shows an increased prevalence in certain breeds, and recent work in English Cocker Spaniels suggests it is part of a polysystemic immune-mediated disease in this breed. The histological and clinical appearance is different in different breeds, suggesting that etiologies may also be different. Diagnosis is challenging because the sensitivities of the available noninvasive tests are relatively low. However, with an increased index of suspicion, clinicians will recognize more cases that will allow them to institute supportive treatment to improve the quality of life of the patient.     

Long-term impacts of prescribed burning on regional extent and incidence of wildfires—Evidence from 50 years of active fire management in SW Australian forests

Prescribed burning is advocated for the sustainable management of fire-prone ecosystems for its capacity to reduce fuel loads and mitigate large high-intensity wildfires. However, there is a lack of comprehensive field evidence on which to base predictions of the benefits of prescribed burning for meeting either wildfire hazard reduction or conservation goals. Australian eucalypt forests are among the very few forest types in the world where prescribed burning has been practised long enough and at a large enough spatial scale to quantify its effect on the incidence and extent of unplanned fires. Nevertheless even for Australian forests evidence of the effectiveness of prescribed burning remains fragmented and largely unpublished in the scientific literature.     

Towards the identification of ecological management units: A multidisciplinary approach for the effective management of bottlenose dolphins in the southern Iberian Peninsula

相似文献   

Phage Therapy is Effective in Protecting Honeybee Larvae from American Foulbrood Disease

American foulbrood disease has a major impact on honeybees (Apis melifera) worldwide. It is caused by a Gram-positive, spore-forming bacterium, Paenibacillus larvae. The disease can only affect larval honeybees, and the bacterial endospores are the infective unit of the disease. Antibiotics are not sufficient to combat the disease due to increasing resistance among P. larvae strains. Because of the durability and virulence of P. larvae endospores, infections spread rapidly, and beekeepers are often forced to burn beehives and equipment. To date, very little information is available on the use of bacteriophage therapy in rescuing and preventing American foulbrood disease, therefore the goal of this study was to test the efficacy of phage therapy against P. larvae infection. Out of 32 previously isolated P. larvae phages, three designated F, WA, and XIII were tested on artificially reared honeybee larvae infected with P. larvae strain NRRL B-3650 spores. The presence of P. larvae DNA in dead larvae was confirmed by 16S rRNA gene-specific polymerase chain reaction amplification. Survival rates for phage-treated larvae were approximately the same as for larvae never infected with spores (84%), i.e., the phages had no deleterious effect on the larvae. Additionally, prophylactic treatment of larvae with phages before spore infection was more effective than administering phages after infection, although survival in both cases was higher than spores alone (45%). Further testing to determine the optimal combination and concentration of phages, and testing in actual hive conditions are needed.