Purification, structural features and immunostimulatory activity of novel polysaccharides from Caulerpa lentillifera

2018 ◽  
Vol 108 ◽  
pp. 314-323 ◽  
Author(s):  
Yujiao Sun ◽  
Guiping Gong ◽  
Yiming Guo ◽  
Zhongfu Wang ◽  
Shuang Song ◽  
...  
2019 ◽  
Vol 10 (7) ◽  
pp. 4315-4329 ◽  
Author(s):  
Yujiao Sun ◽  
Yang Liu ◽  
Chunqing Ai ◽  
Shuang Song ◽  
Xuefeng Chen

Caulerpa lentilliferapolysaccharides could serve as novel prebiotics and immunostimulators, since they improve the immune-related factors and modulate the gut microbiota in cytoxan-induced immunosuppressed mice.


Molecules ◽  
2019 ◽  
Vol 24 (2) ◽  
pp. 356
Author(s):  
Young-Ran Song ◽  
Ah-Ram Han ◽  
Tae-Gyu Lim ◽  
Ji-Hyun Kang ◽  
Hee-Do Hong

In this study, we investigated changes in the structural and immunological features of polysaccharides (S1-PLE0, S2-PLE0, and S3-PLE0) extracted from persimmon leaves at three different growth stages. Physicochemical analyses revealed that their chemical compositions, molecular weight distributions, and linkage types differed. High-performance size-exclusion chromatograms showed that the molecular weights of the polysaccharides increased during successive growth stages. In addition, seasonal variation of persimmon leaves affected the sugar compositions and glycosidic linkages in the polysaccharides. S2-PLE0 was composed of comparatively more galactose, arabinose, rhamnose, xylose, and galacturonic acid, showing the presence of β-glucopyranoside linkages. Significant differences also occurred in their immunostimulatory effects on RAW264.7 macrophages, with respect to which their activities could be ordered as S2-PLE0 > S3-PLE0 > S1-PLE0. Evidently, S2-PLE0 showed the greatest immunostimulatory activity by enhancing the phagocytic capacity and promoting nitric oxide (NO) and cytokines secretion through the upregulation of their gene expression in macrophages. These results suggest that differences in the structural features of polysaccharides according to the different maturity of persimmon leaves might impact their immunostimulatory properties. The results also provide a basis for optimizing persimmon leaf cultivation strategies for food and medical uses of the polysaccharides.


2020 ◽  
Vol 20 (2) ◽  
pp. 96-106
Author(s):  
Yue Zhao ◽  
Bocheng Yan ◽  
Zhaoyu Wang ◽  
Mingjing Li ◽  
Wei Zhao

Natural polysaccharide is a kind of natural macromolecular which can be extracted from plants, fungi, algae, animals, and bacteria. The monosaccharide compositions and glucosidic bonds of polysaccharides from different origins vary substantially. Natural polysaccharides have been shown to possess complex, important and multifaceted biological activities including antitumor, anticoagulant, antioxidative, antiviral, immunomodulatory, antihyperlipidemic and antihepatotoxic activities. Their properties are mainly due to their structural characteristics. It is necessary to develop polysaccharide immunomodulators with potential for preventive or therapeutic action. The present paper summarizes the structural features, immunostimulatory activity and the immunomodulatory mechanisms of natural polysaccharides. In particular, it also provides an overview of representative natural polysaccharide immunomodulators.


2010 ◽  
Vol 79 (2) ◽  
pp. 397-402 ◽  
Author(s):  
Joana Simões ◽  
Fernando M. Nunes ◽  
Maria do Rosário M. Domingues ◽  
Manuel A. Coimbra

Author(s):  
O.C. de Hodgins ◽  
K. R. Lawless ◽  
R. Anderson

Commercial polyimide films have shown to be homogeneous on a scale of 5 to 200 nm. The observation of Skybond (SKB) 705 and PI5878 was carried out by using a Philips 400, 120 KeV STEM. The objective was to elucidate the structural features of the polymeric samples. The specimens were spun and cured at stepped temperatures in an inert atmosphere and cooled slowly for eight hours. TEM micrographs showed heterogeneities (or nodular structures) generally on a scale of 100 nm for PI5878 and approximately 40 nm for SKB 705, present in large volume fractions of both specimens. See Figures 1 and 2. It is possible that the nodulus observed may be associated with surface effects and the structure of the polymers be regarded as random amorphous arrays. Diffraction patterns of the matrix and the nodular areas showed different amorphous ring patterns in both materials. The specimens were viewed in both bright and dark fields using a high resolution electron microscope which provided magnifications of 100,000X or more on the photographic plates if desired.


Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.


Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.


Author(s):  
R.M. Glaeser ◽  
S.B. Hayward

Highly ordered or crystalline biological macromolecules become severely damaged and structurally disordered after a brief electron exposure. Evidence that damage and structural disorder are occurring is clearly given by the fading and eventual disappearance of the specimen's electron diffraction pattern. The fading and disappearance of sharp diffraction spots implies a corresponding disappearance of periodic structural features in the specimen. By the same token, there is a oneto- one correspondence between the disappearance of the crystalline diffraction pattern and the disappearance of reproducible structural information that can be observed in the images of identical unit cells of the object structure. The electron exposures that result in a significant decrease in the diffraction intensity will depend somewhat upon the resolution (Bragg spacing) involved, and can vary considerably with the chemical makeup and composition of the specimen material.


Author(s):  
Godfrey C. Hoskins ◽  
Betty B. Hoskins

Metaphase chromosomes from human and mouse cells in vitro are isolated by micrurgy, fixed, and placed on grids for electron microscopy. Interpretations of electron micrographs by current methods indicate the following structural features.Chromosomal spindle fibrils about 200Å thick form fascicles about 600Å thick, wrapped by dense spiraling fibrils (DSF) less than 100Å thick as they near the kinomere. Such a fascicle joins the future daughter kinomere of each metaphase chromatid with those of adjacent non-homologous chromatids to either side. Thus, four fascicles (SF, 1-4) attach to each metaphase kinomere (K). It is thought that fascicles extend from the kinomere poleward, fray out to let chromosomal fibrils act as traction fibrils against polar fibrils, then regroup to join the adjacent kinomere.


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