Glucosides of Catechin and Epigallocatechin Gallate: Enzymatic Synthesis to Improve Its Biological Activity

Polyphenols are secondary metabolites of plants, which are responsible for prevention of many diseases. Polyvinylpolypyrrolidone (PVPP) has a high affinity towards polyphenols. This method involves the use of PVPP column to remove polyphenols under centrifugal force. Standards of gallic acid, epigallocatechin gallate, vanillin, and tea extracts(Camellia sinensis)were used in this study. PVPP powder was packed in a syringe with different quantities. The test samples were layered over the PVPP column and subjected to centrifugation. Supernatant was tested for the total phenol content. The presence of phenolic compounds and caffeine was screened by HPLC and measuring the absorbance at 280. The antioxidant capacity of standards and tea extracts was compared with the polyphenol removed fractions using DPPH scavenging assay. No polyphenols were found in polyphenolic standards or tea extracts after PVPP treatment. The method described in the present study to remove polyphenols is simple, inexpensive, rapid, and efficient and can be employed to investigate the contribution of polyphenols present in natural products to their biological activity.

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Virus-Like Particles in a Human Breast Cancer: Structural Similarity to Previously Reported Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072332 ◽

1973 ◽

Vol 31 ◽

pp. 378-379

Author(s):

G. Kasnic ◽

S. E. Stewart ◽

C. Urbanski

Keyword(s):

Breast Cancer ◽

Biological Activity ◽

Human Breast Cancer ◽

Osteogenic Sarcoma ◽

Human Tumor ◽

Structural Similarity ◽

Cell Tumor ◽

Human Breast ◽

Human Tumor Cell ◽

Type Particle

We have reported the maturation of an intracisternal A-type particle in murine plasma cell tumor cultures and three human tumor cell cultures (rhabdomyosarcoma, lung adenocarcinoma, and osteogenic sarcoma) after IUDR-DMSO activation. In all of these studies the A-type particle seems to develop into a form with an electron dense nucleoid, presumably mature, which is also intracisternal. A similar intracisternal A-type particle has been described in leukemic guinea pigs. Although no biological activity has yet been demonstrated for these particles, on morphologic grounds, and by the manner in which they develop within the cell, they may represent members of the same family of viruses.

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Effects of Vincristine on Endothelial Microtubules in the Spinal Cord

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090270 ◽

1976 ◽

Vol 34 ◽

pp. 58-59

Author(s):

John L. Beggs ◽

John D. Waggener ◽

Wanda Miller

Keyword(s):

Spinal Cord ◽

Biological Activity ◽

Horseradish Peroxidase ◽

Transport Mechanism ◽

Vasogenic Edema ◽

Vesicular Transport ◽

Close Proximity

Microtubules (MT) are versatile organelles participating in a wide variety of biological activity. MT involvement in the movement and transport of cytoplasmic components has been well documented. In the course of our study on trauma-induced vasogenic edema in the spinal cord we have concluded that endothelial vesicles contribute to the edema process. Using horseradish peroxidase as a vascular tracer, labeled endothelial vesicles were present in all situations expected if a vesicular transport mechanism was in operation. Frequently,labeled vesicles coalesced to form channels that appeared to traverse the endothelium. The presence of MT in close proximity to labeled vesicles sugg ested that MT may play a role in vesicular activity.

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