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341.
微量元素和重金属是评价中成药质量的重要指标。文章应用ICP-MS分析了航天育种牛膝中微量元素和重金属的含量。结果表明航天育成的牛膝中含有丰富的对人体有益的元素,特别是Ca,Fe,Zn,Mn,Cu,Se和Mo,含量分别达到9 182.252 μg·g-1·DW,310.5 μg·g-1·DW,24.718 μg·g-1·DW,18 416.97 ng·g-1·DW,5 518.97 ng·g-1·DW,1 747.692 ng·g-1·DW和211.87 ng·g-1·DW,这对人类健康意义重大。重金属(As,Pb,Hg,Cd和Cr)的含量分别是514.332 ng·g-1·DW,1 657.65 ng·g-1·DW,13.212 ng·g-1·DW,49.22 ng·g-1·DW和922.038 ng·g-1·DW,含量偏高但符合相关标准。除了品种以外,栽培中药材时选择优质的土壤和合适的栽培条件,是提高微量元素含量和有效控制重金属含量的重要措施。  相似文献   
342.
Polysaccharides from Flos Sophorae Immaturus (FSI) are one of its pharmacological compounds that can perform effective activities. Aiming to extract the most effective polysaccharides against hepatocellular carcinoma (HCC), the polysaccharides were separated from FSI through ultrasonic microwave extraction, and the first comparison was carried out on the characterization of the structure and its cytotoxic properties on HCC SMMC 7721 cells of undeproteinized purified polysaccharides (PFSI-1) and papain-deproteinized polysaccharides (PFSI-2) from FSI. The findings indicated that PFSI-1 and PFSI-2 had characteristic absorption peaks of polysaccharides; PFSI-1 contained three monosaccharides and PFSI-2 contained ten; and SEM, AFM, and NMR were consistent with the verification of IR polysaccharide characteristics, suggesting probable additional latent activities. The pharmacotoxic effects of both PFSI-1 and PFSI-2 on SMMC 7721 cells (p < 0.05), attenuated the migration ability of SMMC 7721 cells (p < 0.05) and promoted apoptosis (p < 0.05), with an increase in G0/G1-phase cells and decrease in S-phase cells in the PFSI-1 as well as a decrease in G0/G1-phase cells, increase in S-phase cells, and decrease in apoptosis in the PFSI-2 (p < 0.05). The significant cytotoxic effect of PFSI-2 on SMMC 7721 cells (p < 0.05) and its protective effect on human hepatic L02 cells (HL-7702) at low concentrations (p > 0.05) could indicate its potential as a new drug for the treatment of HCC.  相似文献   
343.
A polysaccharide from Gastrodia elata (named GEP-1) was isolated with a DEAE-52 column and Sephadex G-100 column. The structural characteristics showed that GEP-1 was mainly composed of glucose (92.04%), galactose (4.79%) and arabinose (2.19%) with a molecular weight of 76.444 kDa. The polydispersity (Mw/Mn) of GEP-1 was 1.25, indicating that the distribution of molar mass (Mw) was relatively narrow, which suggested that GEP-1 was a homogeneous polysaccharide. Moreover, the molecular conformation plot of the root mean square (RMS) radius (<rg2> 1/2) versus Mw yielded a line with a slope less than 0.33 (0.15 ± 0.02), displaying that GEP-1 is a compact and curly spherical molecule in NaNO3 aqueous solution. NMR and methylation analyses revealed that the main chain structure of GEP-1 was α-(1→4)-glucans. Furthermore, it was proven that GEP-1 possessed cytoproliferative and enhancing phagocytic activities and induced cytokine (TNF-α, IL1-β) and nitric oxide (NO) release in macrophages by upregulating the related gene expression. In addition, the RNA-seq results suggested that the GEP-1-induced immunomodulatory effect was mainly caused by activation of the NF-κB signaling pathway, which was further verified by NF-κB ELISA and pathway inhibition assays. As a result, GEP-1 exhibits the potential to be developed as a novel cheap immunostimulant without obvious toxicity.  相似文献   
344.
Vascular retinopathy is a pathological change in the retina caused by ocular or systemic vascular diseases that can lead to blurred vision and the risk of blindness. Lycium barbarum polysaccharides (LBPs) are extracted from the fruit of traditional Chinese medicine, L. barbarum. They have strong biological activities, including immune regulation, antioxidation, and neuroprotection, and have been shown to improve vision in numerous studies. At present, there is no systematic literature review of LBPs on vascular retinal prevention and treatment. We review the structural characterization and extraction methods of LBPs, focus on the mechanism and pharmacokinetics of LBPs in improving vascular retinopathy, and discuss the future clinical application and lack of work. LBPs are involved in the regulation of VEGF, Rho/ROCK, PI3K/Akt/mTOR, Nrf2/HO-1, AGEs/RAGE signaling pathways, which can alleviate the occurrence and development of vascular retinal diseases in an inflammatory response, oxidative stress, apoptosis, autophagy, and neuroprotection. LBPs are mainly absorbed by the small intestine and stomach and excreted through urine and feces. Their low bioavailability in vivo has led to the development of novel dosage forms, including multicompartment delivery systems and scaffolds. Data from the literature confirm the medicinal potential of LBPs as a new direction for the prevention and complementary treatment of vascular retinopathy.  相似文献   
345.
A water-soluble sulfated polysaccharide, F2-1, was obtained from the marine green alga, Codium isthmocladum, using ion-exchange and size-exclusion chromatography. Structure analysis showed that the F2-1 was a sulfated arabinan comprising Ara, Rha, Man, Gal, and Xyl with an 18% sulfate content and a molecular weight of 100 kDa. Methylation analysis combined with desulfation, GC-MS, IR, and NMR spectroscopy showed that the backbone of F2-1 was →4)-β-L-Arap(1→ residue. Its 2-O and/or 3-O positions showed sulfate modification; additionally, the 2-O or 3-O position showed branch points. The side chains were composed of →5)-β-D-Galf, (1→2,6)-β-D-Galf(1→, (1→2)-β-L-Rhap4S, →4)-α-D-Glcp(1→, and terminal α-D-Galp(1→ and β-D-Xylp(1→. Polysaccharides containing β-D-galactofuranose are rarely found in seaweed. F2-1 exhibited significant anticoagulant activity in vitro. Our findings suggested that the green-tide alga, Codium isthmocladum, can be considered as a useful resource for bioactive polysaccharides.  相似文献   
346.
杏鲍菇多糖和微量元素的含量测定   总被引:1,自引:0,他引:1  
采用苯酚-硫酸法测定了景宁产杏鲍菇中多糖的含量,并采用等离子体发射光谱法(ICP-AES法)测定了其微量元素的含量.结果表明,多糖测定波长为490nm,在2.04~10.20μg/mL范围内吸光度与被测物含量呈良好的线性关系,r=O.9992,方法的平均回收率为100.8%,RSD=1.3%.杏鲍菇含有丰富的多糖及铜、铁、锰、锌、硒等微量元素,药食两用,具有很高的经济价值和药用价值.多糖测定方法简便、准确、重现性好,可作为杏鲍菇多糖含量的测定方法.  相似文献   
347.
Nimesulide (NIM, N-(4-nitro-2-phenoxyphenyl)methanesulfonamide) is a relatively new nonsteroidal anti-inflammatory analgesic drug. It is practically insoluble in water (<0.02 mg/mL). This very poor aqueous solubility of the drug may lead to low bioavailability. The objective of the present study was to investigate the possibility of improving the solubility and the bioavailability of NIM via complexation with polysaccharide arabinogalactan (AG), disodium salt of glycyrrhizic acid (Na2GA), hydroxypropyl-β-cyclodextrin (HP-β-CD) and MgCO3. Solid dispersions (SD) have been prepared using a mechanochemical technique. The physical properties of nimesulide SD in solid state were characterized by differential scanning calorimetry and X-ray diffraction studies. The characteristics of the water solutions which form from the obtained solid dispersions were analyzed by reverse phase and gel permeation HPLC. It was shown that solubility increases for all complexes under investigation. These phenomena are obliged by complexation with auxiliary substances, which was shown by 1H-NMR relaxation methods. The parallel artificial membrane permeability assay (PAMPA) was used for predicting passive intestinal absorption. Results showed that mechanochemically obtained complexes with polysaccharide AG, Na2GA, and HP-β-CD enhanced permeation of NIM across an artificial membrane compared to that of the pure NIM. The complexes were examined for anti-inflammatory activity on a model of histamine edema. The substances were administered per os to CD-1 mice. As a result, it was found that all investigated complexes dose-dependently reduce the degree of inflammation. The best results were obtained for the complexes of NIM with Na2GA and HP-β-CD. In noted case the inflammation can be diminished up to 2-fold at equal doses of NIM.  相似文献   
348.
Ferulated polysaccharides such as pectin and arabinoxylan form covalent gels which are attractive for drug delivery or cell immobilization. Saccharomyces boulardii is a probiotic yeast known for providing humans with health benefits; however, its application is limited by viability loss under environmental stress. In this study, ferulated pectin from sugar beet solid waste (SBWP) and ferulated arabinoxylan from maize bioethanol waste (AX) were used to form a covalent mixed gel, which was in turn used to entrap S. boulardii (2.08 × 108 cells/mL) in microbeads using electrospray. SBWP presented a low degree of esterification (30%), which allowed gelation through Ca2+, making it possible to reduce microbead aggregation and coalescence by curing the particles in a 2% CaCl2 cross-linking solution. SBWP/AX and SBWP/AX+ S. boulardii microbeads presented a diameter of 214 and 344 µm, respectively, and a covalent cross-linking content (dimers di-FA and trimer tri-FA of ferulic acid) of 1.15 mg/g polysaccharide. The 8-5′, 8-O-4′and 5-5′di-FA isomers proportions were 79%, 18%, and 3%, respectively. Confocal laser scanning microscopy images of propidium iodide-stained yeasts confirmed cell viability before and after microbeads preparation by electrospray. SBWP/AX capability to entrap S. boulardii would represent an alternative for probiotic immobilization in tailored biomaterials and an opportunity for sustainable waste upcycling to value-added products.  相似文献   
349.
Enantioseparation of limonene‐based bicyclic 1,3‐aminoalcohols and 1,3,5‐ and 1,3,6‐aminodiols was performed by normal‐phase high‐performance liquid chromatographic and supercritical fluid chromatographic (SFC) methods on polysaccharide‐based chiral stationary phases. The effects of the composition of the mobile phase, the column temperature and the structures of the analytes and chiral selectors on retention and selectivity were investigated by normal‐phase LC and SFC technique. Thermodynamic parameters derived from selectivity–temperature‐dependence studies were found to be dependent on the chromatographic method applied, the nature of the chiral selector and the structural details of the analytes. Enantiorecognition in most cases was enthalpically driven but an unusual temperature behavior was also observed: decreased retention times were accompanied by improved separation factors with increasing temperature, i.e. some entropically driven separations were also observed. The elution sequence was determined in all cases. The separation of the stereoisomers was optimized in both chromatographic modalities.  相似文献   
350.
灵芝多糖的结构特征分析   总被引:5,自引:0,他引:5  
采用沸水回流法从灵芝子实体中提取多糖,经Sevage法除蛋白,乙醇沉淀,离心、透析、膜分离,浓缩、冻干后得灵芝多糖。经HIO4氧化、Smith降解及甲基化反应,并利用多糖及刚果红混合液在碱性溶液中的波长的红移变化,通过UV-VIS,IR,GC,GC-MS,NMR对灵芝水提多糖的结构特征及三螺旋体结构进行分析研究。结果表明:灵芝多糖含有三螺旋体构型,GC-MS分析灵芝多糖的主要单糖组分为葡萄糖,还有少量的半乳糖、甘露糖、木糖和艾杜糖,IR及1HNMR分析多糖为β-构型,HIO4氧化、Smith降解和甲基化分析表明:多糖主要为(1→3)糖苷键连接构型,并伴有少量的1→6位支链键连接的结构,灵芝多糖是由D-葡萄糖单元通过β-(1→3)糖苷键连接葡聚多糖,其主要构型特征为(1→3)β-D-线性连接的骨架结构。  相似文献   
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