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21.
功能性低聚糖的开发现状及在食品中的应用   总被引:7,自引:0,他引:7  
论述了功能性低聚糖发展的背景、我国主要开发的功能性低聚糖的种类在食品中应用的状况。讨论了我国一些企业开发和生产功能性低聚糖的情况及市场前景。  相似文献   
22.
低聚糖在饲料工业中的应用   总被引:13,自引:2,他引:13  
阐述了饲料工业中应用低聚糖的背景、低聚糖的生理功能、不同种类低聚糖对肠道微生物的营养及低聚糖在饲料中的实际应用效果。  相似文献   
23.
大豆低聚糖的制备工艺研究   总被引:4,自引:0,他引:4  
研究从脱脂豆粕中提取大豆低聚糖的制备工艺。经多次实验,确定了浸提、活性炭脱色和离子交换脱盐等过程的优化工艺参数,并对成品糖浆的成分进行了测定。  相似文献   
24.
    
Phosphoryl oligosaccharides of calcium (POs-Ca) is a calcium salt of phosphoryl maltooligosaccharides made from potato starch. POs-Ca is highly water-soluble and can supply both the calcium ion and acidic oligosaccharides in an aqueous solution. In this study, we investigated the effects of POs-Ca on the mycelial growth and fruiting body yield of Pleurotus ostreatus , which is one of the most widely cultivated edible mushrooms in the world. We cultivated the mushroom using both potato dextrose agar (PDA) medium and sawdust-based medium, with added calcium salts. The addition of POs-Ca into the PDA medium with a calcium concentration of 10 mg increased mycelial growth significantly ( p < 0.05, vs . control). POs-Ca addition to the sawdust-based medium at concentrations of 1.0 to 3.0 g/100 g medium increased the amount of calcium in the fruiting bodies but did not affect the length of the cultivation period or the weight of the fruiting body. The calcium content in the fruiting body increased 12-fold when compared to the control. On the other hand, neither the CaHPO 4 ・2H 2 O group nor the CaHPO 4 ・2H 2 O with oligosaccharides group showed changes in the calcium content of the fruiting bodies. Our results indicate that the use of POs-Ca in mushroom cultivation allows for the possibility of developing new functional foods like calcium-enriched edible mushrooms. This is the first report describing the effects of POs-Ca on mushroom cultivation.  相似文献   
25.
Mass spectrometry of oligosaccharides   总被引:12,自引:0,他引:12  
Glycosylation is a common post-translational modification to cell surface and extracellular matrix (ECM) proteins as well as to lipids. As a result, cells carry a dense coat of carbohydrates on their surfaces that mediates a wide variety of cell-cell and cell-matrix interactions that are crucial to development and function. Because of the historical difficulties with the analysis of complex carbohydrate structures, a detailed understanding of their roles in biology has been slow to develop. Just as mass spectrometry has proven to be the core technology behind proteomics, it stands to play a similar role in the study of functional implications of carbohydrate expression, known as glycomics. This review summarizes the state of knowledge for the mass spectrometric analysis of oligosaccharides with regard to neutral, sialylated, and sulfated compound classes. Mass spectrometric techniques for the ionization and fragmentation of oligosaccharides are discussed so as to give the reader the background to make informed decisions to solve structure-activity relations in glycomics.  相似文献   
26.
对黑莓果胶寡糖进行抗氧化活性研究,探究其自由基清除能力。对黑莓果胶进行提取,并利用果胶酶对其进行酶解,通过分级醇沉制得黑莓果胶寡糖。以DPPH、ABTS、羟自由基清除能力验证不同黑莓果胶寡糖体外抗氧化活性。结果表明,4倍醇沉寡糖对DPPH、ABTS自由基的IC50分别为0.59、4.75 mg/m L。10倍醇沉果胶寡糖对这两种自由基的清除作用更强,IC50分别为0.40、2.79 mg/m L。黑莓果胶寡糖具有显著的抗氧化活性,对DPPH自由基、ABTS自由基有很强的清除作用,且具有明显的量效关系。   相似文献   
27.
陈献富  季华  范益群 《化工进展》2019,38(1):394-403
功能性低聚糖具有抗肿瘤、抗放射、抗凝血、消炎和调节免疫力等医疗保健作用,广泛应用于食品科学和生物医药等领域。纳滤作为一种高效的膜分离技术,在功能性低聚糖的分离与纯化中的应用得到越来越多的关注。本文分析了纳滤膜对功能性低聚糖的分离机理,综述了纳滤膜在功能性多糖分离纯化中的应用进展,讨论了纳滤分离过程的影响因素,主要包括功能性多糖料液的性质、膜过程的操作参数以及膜材料本身的性质等。其中,料液的性质主要体现在组成、浓度、黏度等方面;操作参数主要体现在压力、温度、膜面流速和pH等方面;而膜材料的性质主要体现在微结构和表面性质两个方面。最后,进一步指出纳滤膜技术用于功能性多糖分离纯化时在设备成本、膜材料及膜污染等方面存在的问题,并对未来纳滤膜技术在低成本专用膜材料及系统开发和膜污染控制方面的研究进行了展望。  相似文献   
28.
The present work assessed the protective effect of feruloyl oligosaccharides (FOs), the ferulic acid ester of oligosaccharides from wheat bran, against oxidative DNA damage in normal human peripheral blood lymphocytes induced by hydrogen peroxide (H2O2). The DNA damage was measured by using the single cell gel electrophoresis assay (comet assay). Lymphocytes were subjected to DNA damage by exposure to a range of H2O2 concentrations (10–200 μmol/l). H2O2, at a concentration of 200 μmol/l, resulted in nearly all cells being highly damaged. FOs showed no cytotoxicity and genotoxicity to normal human lymphocytes at the tested concentrations (10–500 μmol/l). In addition, DNA damage in human lymphocytes induced by 100 μmol/l H2O2 was inhibited by FOs in a concentration-dependent fashion with 91.1% inhibition of lymphocyte DNA damage at 500 μmol/l as compared with the control. The results suggest that water-soluble FOs from wheat bran are able to enhance the ability of human lymphocytes to resist H2O2 induced oxidative damage.  相似文献   
29.
    
Prebiotics have long been used to modulate the gut microbiota and improve host health. Most established prebiotics are nondigestible carbohydrates, especially short-chain oligosaccharides. Recently, gluco-oligosaccharides (GlcOS) with 2–10 glucose residues and one or more O-glycosidic linkage(s) have been found to exert prebiotic potentials (not fully established prebiotics) because of their selective fermentation by beneficial gut bacteria. However, the prebiotic effects (non-digestibility, selective fermentability, and potential health effects) of GlcOS are highly variable due to their complex structure originating from different synthesis processes. The relationship between GlcOS structure and their potential prebiotic effects has not been fully understood. To date, a comprehensive summary of the knowledge of GlcOS is still missing. Therefore, this review provides an overview of GlcOS as potential prebiotics, covering their synthesis, purification, structural characterization, and prebiotic effect evaluation. First, GlcOS with different structures are introduced. Then, the enzymatic and chemical processes for GlcOS synthesis are critically reviewed, including reaction mechanisms, substrates, catalysts, the structures of resultant GlcOS, and the synthetic performance (yield and selectivity). Industrial separation techniques for GlcOS purification and structural characterization methods are discussed in detail. Finally, in vitro and in vivo studies to evaluate the non-digestibility, selective fermentability, and associated health effects of different GlcOS are extensively reviewed with a special focus on the GlcOS structure–function relationship.  相似文献   
30.
    
Tissue repair and regeneration in ischemic areas require effective strategies for angiogenesis and microcirculation reconstruction. In this research, extracellular vesicles (EVs) derived from hemangioma stem cells (HemSC) are used as bio-functional materials for angiogenesis. In addition, a novel thermo-sensitive hydrogel based on chitosan (CS) and modified with hyaluronic oligosaccharides (oHA), is specially developed as an ideal carrier of HemSC-EVs. The oHA/CSgel provides a sustained-release delivery system for EVs, enhances the angiogenic function of HemSC-EVs, and exerts other bio-functions to comprehensively accelerate tissue repair. The physical properties of EVs@oHA/CSgel proved to be soft, highly elastic deformable, biocompatible, and can maintain the shape and structure of EVs. In vitro co-culture assay verifies the angiogenic effect of EVs@oHA/CSgel, and this effect is also evaluated in a diabetic wound model. Compared to untreated group, the EVs@oHA/CSgel group has only 26.9% wound area on day 14, and 226.8% blood flux mark on day 17. Pharmacological mechanisms of HemSC-EVs are predicted by RNA-seq, and cluster analysis of miRNAs predicted targets presents several up-regulated biological processes involving in angiogenesis and wound healing. In conclusion, it is suggested that EVs@oHA/CSgel as a satisfying therapeutic system for microcirculation reconstruction in tissue repair.  相似文献   
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