Structural characterization and immune-enhancing activity of a novel high-molecular-weight polysaccharide from Cordyceps militaris.

A novel homogeneous polysaccharide (CMP-III) was extracted and purified from C. militaris. Structural characterization revealed that CMP-III had an average molecular weight of 4.796 × 104 kDa and consisted of glucose, mannose and galactose with the molar ratio of 8.09:1.00:0.25. The main linkage types of CMP-III consisted of 1 â†’ 4)-α-D-Glc (70.08%), 1 â†’ 4,6)-α-D-Man (9.59%), 1→)-α-D-Man (10.79%) and 1 → 2,6)-α-D-Gal (3.93%) based on methylation and NMR analysis. The immunomodulatory assay indicated that CMP-III significantly promoted macrophage phagocytosis and secretion of NO, TNF-α and IL-6. Further study suggested that macrophage activated by CMP-III involved mitogen-activated protein kinases (MAPKs) and nuclear factor kappa-B (NF-κB) signaling pathways. Overall, these results suggested that CMP-III could be developed as a potent immunomodulatory agent for use in functional foods and dietary supplements.

Structure and bioactivity of a polysaccharide containing uronic acid from Polyporus umbellatus sclerotia.

Polyporus umbellatus is a medicinal fungus, has been used in traditional Chinese medicine for thousands years for treatment of edema, scanty urine, vaginal discharge, jaundice and diarrhea. The structure of a soluble polysaccharide (named PUP80S1), purified from the sclerotia of Polyporus umbellatus was elucidated by gas chromatography (GC), GC-mass spectrometry and nuclear magnetic resonance spectroscopy. PUP80S1 is a branched polysaccharide containing approximately 8.5% uronic acid and having an average molecular weight of 8.8kDa. Atomic force microscopy of PUP80S1 reveals a globular chain conformation in water. Antioxidant tests, Oxygen radical absorption capacity and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays indicate that PUP80S1 possesses significant antioxidant activity. But the related polysaccharide, PUP60S2, which contains more uronic acid residues and a higher level of branching, shows better antioxidant activity. These results suggest that structure features of polysaccharides play an important role in their physiological functions.

Development, physiochemical characterization and forming mechanism of Flammulina velutipes polysaccharide-based edible films.

Edible films of Flammulina velutipes polysaccharide were prepared and characterized in terms of rheological, optical, morphologic, mechanical and barrier properties to evaluate their potential application in food packaging. Results suggested that FVP film prepared by the solution of 1:150 (w/v) had the optimal mechanical property, smooth and uniform surface, and good barrier property to water (37.92±2.00gmm/m(2)hkPa) and oxygen (37.92±2.01meq/kg). The capacity of film-formation might be related to inter-molecular and intra-molecular hydrogen bonds of FVP and formation of ß-glycosidic bonds during the process of film-formation. These findings will contribute to a theoretical basis for the development of FVP film in food packaging.

Hacia una definición de fibra alimentaria / Alimentary fiber definition

La fibra alimentaria (FA) ha sido un tópico de considerable interés para los nutricionistas y médicos en estos últimos 35 años. Este artículo presenta un análisis sobre la definición de fibra alimentaria y la controversia que existe al respecto, así como las nuevas propuestas que han surgido para incluir en su definición. La FA fue definida como: todos los polisacáridos no almidones más la lignina, que no pueden ser digeridos o absorbidos en el intestino delgado humano. Esta definición no incluye otros componentes vegetales tales como: polifenoles, proteínas resistentes y almidones resistente, los cuales son también resistentes a la digestión. Para muchos investigadores, la definición de FA aun no esta concluida o completa. Las investigaciones epidemiológicas han indicado, la posible relación entre las enfermedades más comunes en las modernas sociedades occidentales y la fibra alimentaria.

Dietary fiber (DF) has been a topic of considerable interest among nutritionists and physicians for the last 35 years. This work was basically focused on an analysis of the dietary fiber definition, the currently existing controversy and the new proposal to be included in such a definition. DF was defined as all nonstarch polysaccharides plus lignin, which are not digested or absorbed in the human digestive tract. This definition does not include other vegetable substances, such as, polyphenols, resistant protein or resistant starch, which are also resistant to digestion. For most researchers this definition is not yet complete. Epidemiological investigations, have suggested the possible relationship between the most common diseases in the modern Western societies and the dietary fiber.

Worldwide production of high-fructose syrup and crystalline fructose.

High-fructose syrups (HFS) are now manufactured and used in many countries throughout the world. They are produced from a variety of starch raw materials including corn, rice, tapioca, wheat, cassava, and sugar beet pulp. Production of HFS is highly dependent on local sucrose and economics of agricultural raw materials. HFS is produced and consumed in the largest quantity in the United States by using corn starch as the raw material. Eastern Europe, the former Soviet Union, and Asia are major growth areas for HFS production. Crystalline fructose is now being used in a growing number of food applications but its production represents a small percentage of total fructose sweeteners.