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31.
The Chinese herb Radix astragalus (RA) has been widely used as a dietary supplement in Asia, and there are numerous reports on its bioactivities. However, there are no reports to date regarding the use of Aspergillus spp. in the culture medium of the RA plant for the production of phenolic antioxidants. In this study, utilizing the fungus Aspergillus to ferment the native RA has successfully resulted in a significant increase in the phenolic contents of RA, and the fermented RA also revealed much better antioxidant activity toward 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals, hydroxyl radical, superoxide radical and peroxyl radical than those of unfermented RA. Among these phenolics, a potent novel antioxidant was isolated and identified as 3,4-di(4'-hydroxyphenyl) isobutyric acid with a molecular weight of 272, by ESI-MS (electrospray ionization mass), 1H NMR (nuclear magnetic resonance), 13C NMR, DEPT (distortionless enhancement by polarization transfer)-NMR, HMQC (heteronuclear multiple quantum coherence), and HMBC (heteronuclear multiple bond correlation) spectra. These data demonstrated that the solid-state bioprocessing strategy could be an innovative approach to enhance the antioxidant activity of RA.  相似文献   
32.
采用光学和电子显微镜技术、SDS-PAGE技术、间接免疫酶标光镜定位和胶体金免疫电镜定位技术对银杏枝条中的营养贮藏蛋白质(VSPs)进行分离鉴定,并对其细胞学特性及动态变化规律进行初步研究。研究结果:运用制备型SDS-聚丙烯酰胺凝胶电泳分离并制备银杏32和36ku2种营养贮藏蛋白质抗原,通过免疫新西兰大白兔成功获得银杏32和36ku2种营养贮藏蛋白质的多克隆抗体。银杏VSPs主要分布于落叶期当年生枝条的次生韧皮部细胞中,呈现出团块状、颗粒状和均一状3种形态。在新梢生长期,积累在枝条中的VSPs逐渐降解消失,表现出明显的季节变化。  相似文献   
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To represent nitrogen cycling in a low input grass/legume pasture system, a previously developed, weather-driven grass/white clover growth model has been adapted to become the crop growth component of the soil nitrogen dynamics model SOILN. This provides a means of simulating nitrogen uptake by a grass/white clover crop, an important component of the overall nitrogen balance in low-input grassland systems.
Crop growth is represented by a photosynthesis equation adapted to take account of competition between the two crops for resources of light, water and nitrogen in the soil. Water shortage is represented by linked simulations with the soil water and heat model SOIL, and nitrogen shortage by links with the SOILN model. Nitrogen fixation has been introduced according to an equation for potential fixation reduced by environmental factors, particularly temperature. Transfer of nitrogen-rich clover plant material to the soil nitrogen pools of SOILN (from where it becomes available as a nutrient for grass) is also represented. The model is tested by comparing simulated cut crop yields and nitrogen content of cut material with measured data from perennial ryegrass/white clover at a test site. Soil nitrogen processes in the model are tested by comparing simulated and measured nitrate in drainflows. Apart from some discrepancies between simulated and measured results attributable to the inherent instability of a mixed crop system, agreement is reasonable by the standards of biological system models, indicating that the combined model gives a realistic representation of carbon and nitrogen processes in grassland with a grass, legume mixed crop.  相似文献   
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Plant Foods for Human Nutrition - Highbush (cultivated) and lowbush (wild) are the two major blueberry species in the US market. Eight phenolic acids were detected and quantified from these two...  相似文献   
38.
Soybean(Glycine max[L.]Merr.)is a food and oil crop whose growth and yield are influenced by root and nodule development.In the present study,Gm NMHC5 was found to promote the formation of nodules in overexpressing mutants.In contrast,the number of nodules in Gmnmhc5 edited with CRISPR/Cas9 decreased sharply.In 35 S:Gm NMHC5 mutants,expression levels of genes involved in nodulation were significantly up-regulated.Both in vitro and in vivo biochemical analyses showed that Gm NMHC5 directly interacted with Gm GAI(a DELLA protein),and the content of gibberellin 3(GA3)in overexpressing mutants was lower than that in the wild type.These results revealed that Gm NMHC5 participates in the classical GA signaling pathway,and may regulate the content of GA_3 to match the optimal concentration required for nodule formation,thereby promoting nodulation by directly interacting with Gm GAI.A model illustrating the mechanism by which Gm NMHC5 promotes soybean nodulation is presented.  相似文献   
39.
S Wu  J Sun  Z Tong  X Lan  Z Zhao  D Liao 《Marine drugs》2012,10(5):1066-1080
Lizard fish (Saurida elongata) muscle protein was hydrolyzed using neutral protease to produce protein hydrolysate (LFPH), and the hydrolysis conditions were investigated using response-surface methodology. The optimum conditions for producing peptides with the highest angiotensin-I converting enzyme (ACE)-inhibitory activity were the following: enzyme-to-substrate ratio of 10,000 U/g, temperature of 48 °C, pH 7.0, and hydrolysis time of 2 h. Under these conditions, the ACE-inhibitory activity of LFPH and the degree of hydrolysis were 84% and 24%, respectively. A novel ACE-inhibitory peptide was isolated from LFPH using ultrafiltration, Sephadex G-15, and high-performance liquid chromatography. The amino acid sequence of the ACE-inhibitory peptide was identified as Ser-Pro-Arg-Cys-Arg (SPRCR), and its IC50 was 41 ± 1 µM.  相似文献   
40.
Cinnamate‐4‐hydroxylase (CA4H), a cytochrome P450‐dependent monooxygenase, plays crucial roles in phenylpropanoid metabolism and plant defense. Previously, the authors showed that the expression of CA4H was induced in response to an allelopathic substance in Eupatorium adenophorum. Here, the full‐length cDNA of EaCA4H was cloned by using rapid amplification of cDNA ends. The 1518 bp open reading frame of EaCA4H was deduced to encode a protein of 505 amino acid residues. Like other CA4H proteins, the predicted EaCA4H polypeptides contained conserved domains of cytochrome P450. A Southern blot analysis indicated that at least five copies of EaCA4H exists in the genome of E. adenophorum. Subcellular localization revealed nuclear‐localized EaCA4H–green fluorescent protein fusion protein in onion epidermal cells. Heterologous silencing of endogenous CA4H in tobacco by a conserved EaCA4H fragment resulted in reduced expressions of key enzymatic genes and the production of downstream flavonoids in the phenylpropanoid pathway. Intriguingly, similar effects were observed in transgenic tobacco plants overexpressing EaCA4H. Altogether, the results indicate that the disturbed expression of CA4H in plants leads to relatively low expression levels of key enzymatic genes and the accumulation of the flavonoids that are involved in phenylpropanoid metabolism.  相似文献   
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