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1.
In this work, spray-dried lipid systems based on soy phosphatidylcholine, cholesterol and lauroyl polyoxylglycerides for entrapping Green tea polyphenols were produced. The aim was to study the effects of the encapsulating composition and spray drying conditions on the system performance and physicochemical product properties. The spray dryer powder production yield falls around 50.7?±?2.8%, which is typical for lab scale spray dryers. Wrinkled and rounded particles, with low surface porosities were generated, independent of the drying carriers (trehalose or lactose) used. The product showed high encapsulation efficiency of Green tea polyphenols, which was promptly redispersible in water. It presented low density, and good compressive and flow properties. The results herein reported confirm the feasibility of the entrapment of Green tea polyphenols in lipid-based compositions by spray drying in presence of the drying carriers evaluated. The spray-dried microparticles show high potential to be used as additive in food, nutraceutical and pharmaceutical products. 相似文献
2.
Fusarium head blight (FHB), incited by Fusarium graminearum Schwabe is one of the most devastating diseases of wheat. Primary inoculum generated on crop residue is the driving force
of FHB epidemics. Fusarium survival on crop residues is affected by soil microbial antagonists. The incorporation of green manures has been shown to
increase the density and diversity of microbes in soils, particularly the density and the pathogen-inhibitory activity of
specific bacteria and fungi. Evidence of increased streptomycete populations in soil as a response to green manure incorporation,
and their negative effect on the survival of Fusarium oxysporum Schlechtendahl in soil, suggests their potential use to reduce the survival of related pathogens. There is, however, no precedent
for the use of green manures to promote indigenous streptomycete populations to control FHB. This study investigated the use
of green manures (sorghum–sudangrass hybrid [Sorghum bicolor (L.) Moench–S. bicolor (L.) Moench var. sudanense (Piper)] and common buckwheat [Fagopyrum esculentum (Moench)]) for reducing F. graminearum survival in association with wheat residues. Soil bacterial density, streptomycete density and the density and inhibitory
activity of F. graminearum-antagonists were monitored from planting until 3 and 6 months following the incorporation of green manures in greenhouse
and field experiments, respectively. The decomposition of wheat residues and survival of Fusarium in residues was also assessed. The use of green manures did not statistically impact the survival of F. graminearum in wheat residue. However, green manures promoted the development of higher densities and antagonistic abilities of F. graminearum-antagonists in soils. Additionally, streptomycete densities and F. graminearum-antagonist densities were significantly and positively correlated with reduced survival of Fusarium. The results of our study suggest that the use of green manures can enhance populations of indigenous soil microorganisms
antagonistic to the survival of F. graminearum in wheat residue. 相似文献
3.
The lands including Cave Spring and most of northwest Georgia were held by the Cherokee until Cherokee removal in 1838. In 2010, a two-story pine structure that was encased inside the Green Hotel in downtown Cave Spring, Georgia, was revealed during renovation. Local Cave Spring historians insist the log structure was built by Avery Vann in 1810, making it a Cherokee structure. However, the Gold Lottery maps of 1832 show no structure on lot 871, which today contains the Green Hotel. A construction date also cannot be verified by historical documents, maps, or artifacts discovered around the Green Hotel. The purpose of this research was to determine the construction date of the Green Hotel log structure. Archaeological dating of the window glass thickness of the hotel gave dates of 1810 or 1823. However, the dendroarchaeological dating of the wood indicates cutting dates during the late spring/early summer of 1839. This would indicate that the log structure inside the Green Hotel was not built by Avery Vann or any Cherokee, but by later Euro-American settlers. 相似文献
4.
《Harmful algae》2016
Blooms of the green macroalga Ulva prolifera in the western Yellow Sea occurred every year since 2008, and they have been reported and studied extensively using a variety of means including remote sensing. However, to date, long-term bloom patterns have not been reported except for a few case studies showing examples in different years. Here, using MODIS observations and an objective method to perform statistical analysis, mean Ulva coverage in the western Yellow Sea has been derived and analyzed between 2007 and 2015 at both monthly and annual scales. On annual scale, mean Ulva coverage decreased after 2008, but increased rapidly after 2012 from 8 km2 in 2012 to 116 km2 in 2015 (the largest ever reported in history for this region). In the month of June the mean coverage increased from 18 km2 in 2012 to 363 km2 in 2015. Other than 2009 and 2010, the month of June showed maximum Ulva coverage in every year. These coverage estimates are significantly lower than previously reported values as they represent “pure” algae coverage after taking into account of partial pixel coverage. Several environmental factors were examined in an attempt to determine the reasons behind such long-term changes, yet the results are inconclusive, suggesting a strong necessity of further coordinated and multi-disciplinary researches. 相似文献
5.
Ping Su Anders Henriksson Christina Nilsson Hazel Mitchell 《World journal of microbiology & biotechnology》2008,24(9):1837-1842
The aim of this study was to assess the effect of a commercial green tea extract (TEAVIGO™) on the microbial growth of three
probiotic strains (Lactobacillus and Bifidobacterium), as well as three pathogenic bacteria. MIC and co-culture studies were performed. The MICs of the green tea extract against
Staphylococcus aureus and Streptococcus pyogenes (100 μg ml−1) were considerably lower than those against the probiotic strains tested (>800 μg ml−1) and Escherichia coli (800 μg ml−1). In co-culture studies, a synergistic effect of the probiotic strains and the green tea extract was observed against both
Staph. aureus and Strep. pyogenes. Green tea extract in combination with probiotics significantly reduced the viable count of both pathogens at 4 h and by
24 h had completely abolished the recovery of viable Staph. aureus and Strep. pyogenes. These reductions were more significant than the reductions induced by probiotics or green tea extracts used separately.
These results demonstrate the potential for combined therapy using the green tea extract plus probiotics on microbial infections
caused by Staph. aureus and Strep. pyogenes. As probiotics and the green tea extract are derived from natural products, treatment with these agents may represent important
adjuncts to, or alternatives to, conventional antibiotic therapy. 相似文献
6.
7.
《Journal of molecular biology》2021,433(19):167162
Many proteins that can assemble into higher order structures termed amyloids can also concentrate into cytoplasmic inclusions via liquid–liquid phase separation. Here, we study the assembly of human Golgi-Associated plant Pathogenesis Related protein 1 (GAPR-1), an amyloidogenic protein of the Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1 proteins (CAP) protein superfamily, into cytosolic inclusions in Saccharomyces cerevisiae. Overexpression of GAPR-1-GFP results in the formation GAPR-1 oligomers and fluorescent inclusions in yeast cytosol. These cytosolic inclusions are dynamic and reversible organelles that gradually increase during time of overexpression and decrease after promoter shut-off. Inclusion formation is, however, a regulated process that is influenced by factors other than protein expression levels. We identified N-myristoylation of GAPR-1 as an important determinant at early stages of inclusion formation. In addition, mutations in the conserved metal-binding site (His54 and His103) enhanced inclusion formation, suggesting that these residues prevent uncontrolled protein sequestration. In agreement with this, we find that addition of Zn2+ metal ions enhances inclusion formation. Furthermore, Zn2+ reduces GAPR-1 protein degradation, which indicates stabilization of GAPR-1 in inclusions. We propose that the properties underlying both the amyloidogenic properties and the reversible sequestration of GAPR-1 into inclusions play a role in the biological function of GAPR-1 and other CAP family members. 相似文献
8.
We examined whether actin filaments are involved in the cAMP-dependent activation of a high affinity sodium/glucose cotransporter (SGLT1) using epithelial expression systems. The expression of enhanced green fluorescent protein-tagged SGLT1 (EGFP-SGLT1) in Madin-Darby canine kidney (MDCK) cells was revealed by Western blotting and confocal laser microscopy. 8-Br-cAMP, a membrane permeable cAMP analog, enhanced [14C]-α-methyl glucopyranoside ([14C]-AMG) uptake. Both basal and 8-Br-cAMP-elicited [14C]-AMG uptakes were inhibited by N-(2{[3-(4-bromophenyl)-2-propenyl]-amino}-ethyl)-5-isoquinolinesulfonamide (H-89), a protein kinase A inhibitor, and cytochalasin D, an actin filament formation inhibitor. Furthermore, cytochalasin D inhibited the distribution of EGFP-SGLT1 at the apical surface. These results suggest that the EGFP-SGLT1 protein is functionally expressed in the apical membrane of MDCK cells, and is up-regulated by a cAMP-dependent pathway requiring intact actin filaments. 相似文献
9.
A. C. Kuesel J. Sianoudis D. Leibfritz L. H. Grimme A. Mayer 《Archives of microbiology》1989,152(2):167-171
The green alga Chlorella fusca accumulates polyphosphates under conditions of nitrogen starvation while deassembling the photosynthetic apparatus. The polyphosphate content of cells regreening after resupply with nitrate under different culture conditions was investigated by P-31 in-vivo NMR spectroscopy. Neither phosphate deficiency nor anaerobiosis during the first hours of regreening inhibited the recovery of the cells. Polyphosphates were degraded during regeening. Differences in the amount of polyphosphates of phosphate supplied and deficient cells occurred only after more then 8 h. After 16 h phosphate deficient cells had still 75% of the polyphosphate content of phosphate suppled cells. In cells kept under anaerobic conditions polyphosphate degradation was much higher than in oxygen supplied cells. After 8 h they contained less than 50% of the polyphosphate content of oxygen supplied cells. These data suggest that polyphosphates serve as obligatory phosphate source during regreening and may be used as an energy source.Non standard abbreviations EDTA
Ethylene diamine tetraacetic acid
- FID
Free induction decay
- MOPSO
3-(N-morpholine)-2-hydroxy-propanesulfonic acid
- NMR
Nuclear magnetic resonance
- PP
Polyphosphates
- PP4
central phosphate groups of polyphosphates 相似文献
10.
Summary On a Typic Ustochrept soil incorporation of 10 tons/ha of a green manure plus submergence for 10 days followed by raising upland nursery checked iron chlorosis. In contrast, presubmergence with and without FYM and iron sulfate or pyrite were a failure. Nor weekly sprays with 3.0% iron sulfate were found very effective. The success of green manure plus submergence was associated with the mobilization of soil iron as a result of intense reduction and its subsequent retention in available form at a sufficient high level during the growth of upland nursery. 相似文献