Shortly after anthesis, empty endosperm cells adjacent to the embryo were crushed between the developing embryo and endosperm tissues to form the crushed cell layer. Starch granules in cells adjacent to this layer were hydrolysed and the empty cells were added to the crushed layer. In this way, the crushed layer increased in thickness throughout kernel development. α-Amylase 2 was detected in the crushed cell layer region of barley endosperms during the period that starch granule hydrolysis was occurring. 相似文献
A total of 96 entire male pigs were used to evaluate the effects of feeding raw potato starch (RPS) and live weight (LW; 90, 100 or 115 kg) on skatole, indole and androstenone levels in fat and plasma. Different methods to analyse the compounds were compared. Fat levels of skatole analysed by HPLC and colorimetric methods, and androstenone analysed by HPLC and ELISA, were highly correlated. However, androstenone values obtained by ELISA were overestimated. Feeding RPS reduced skatole levels in plasma and fat but did not affect indole levels. Androstenone levels in plasma measured by direct ELISA were not altered by diet, whereas the levels measured by ELISA with extraction were lower in the pigs fed RPS. Feeding RPS did not reduce androstenone levels in fat. Androstenone levels in fat were higher at 115 than at 90 kg, whereas skatole and indole levels were not affected by LW. 相似文献
ABSTRACT: Flour and starch were produced from 11 cassava genotypes. Starch and total dietary fiber contents were determined using a single-enzyme gravimetric procedure and high-performance anion exchange chromatography, pasting profiles by rotary viscometry, water holding capacity gravimetrically, and granular characteristics by scanning electron microscopy. Starch and total dietary fiber contents varied among genotypes. Flour peak viscosities, setback, and final viscosities differed significantly. Flour water holding capacity correlated with flour peak viscosity (r = 0.7). Starch granules ranged from 9 to 20 μm. Predominant granule shapes were oval, rounded, and truncated. The results provide insights into cassava genotype characteristics, and functionality of cassava starch and flour. 相似文献
Effects of physically or chemically modified celluloses on gelatinization and retrogradation of sweet potato starch were examined by Theological measurements and differential scanning calorimetry. The mixture of sweet potato starch and four modified celluloses (powdered microcrystalline cellulose, alkaline soluble fibrous cellulose, carboxymethylcellulose and methylcellulose) in the ratio of 9 to 1 was used as a model, because that ratio of starch to cellulose is about the same for sweet potato root. Cellulose derivatives generally did not show important effects on gelatinization temperature and enthalpy of gelatinization. Cellulose derivatives which are not water-soluble increased starch retrogradation, while water-soluble methylcellulose unexpectedly prevented retrogradation. 相似文献
Background: Organic porous material is a promising carrier for enhancing the dissolution of poorly water soluble drug. The aim of the present study was to enhance dissolution and oral bioavailability of lovastatin (LV) by preparing a porous starch microsphere foam (PSM) using a novel method, meanwhile, looking into the mechanism of improving dissolution of LV.
Methods: PSM was prepared by the W/O emulsion – freeze thawing method. The porous structure of PSM was characterized by scanning electron microscopy (SEM) and nitrogen adsorption/desorption analysis. The adsorption role of nanopores on the drug dissolution and physical state of LV was systematically studied by instrumental analysis, and in vitro and in vivo drug dissolution studies. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate carrier cytotoxicity.
Results: The SEM images of PSM showed nanometer-sized pores. Physical state characterization indicated that porous structure effectively limited the degree of crystallinity of LV. The results of in vitro and in vivo tests testified that PSM accelerated the release of LV and enhanced its oral bioavailability in comparison with crude LV and commercial capsules. The loaded PSM powder indicated a good physical stability under storage for 12 months. MTT assay shows PSM has no toxicity for Caco-2 cell.
Conclusion: The preparation was a promising method to produce small and uniform PSM with markedly enhanced dissolution rate and oral bioavailability due to the spatial confinement effect of porous structure. The present work demonstrates the significant potential for the use of PSM as a novel delivery system for poorly water soluble drugs. 相似文献