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Many research efforts have been done toward the proofs of the use of plant species in medicinal treatments in recent years. The effect of plants used has been examined traditionally to support treatment of various diseases. An essential kind is biological buffer.
Biological Buffer Series are organic substances that maintain a constant pH over a given range by neutralizing the effects of hydrogen ions. Buffers also provide a pH environment conducive to critical biochemical processes, wherein a significant change in pH can lead to a harmful change in molecular structure, biological activity or functions. They keep the pH constant by taking up protons which are released during reactions, or by releasing protons when they are consumed by reactions. Buffers are a vital component for modeling biological systems and have many uses in cell culture, molecular biology, nucleic acid, protein purification, transformation and transfections.
The quality of a buffer is determined by is resistance to changes in pH when strong acids or bases are added and is measured in the value of its pKa where the larger the value of pKa, the weaker the acid. Knowing the value of pKa is important in dealing with systems involving acid-base equilibria in solution. Most of the buffers used today were developed in 1966 by Norman Good and his colleagues who identified parameters and characteristics of effective buffers. These biological buffers are called Zwitterionic (Good's) bufers.
Another series are Glycoside Series. Cardiac glycosides are a group that comprises the most drug-like molecules subjected to several investigations and they were proved to be fruitful in developing potential drugs. They are chemical compounds responsible for the poisoning of livestock and the treatment of congestive heart failure.
Extracts or latexes of cardiac glycosides plants have been applied to poison arrows in Africa, Asia, and South America for use in hunting and fighting. It is expected to be evolved as a defense way in plants. Cardiac glycosides are steroids having the ability to exert specific powerful action on the cardiac muscle. A very small amount can exert a beneficial simulation on diseased heart. These compounds are primarily valuable in the treatment of congestive heart failure. They increase the force of heart contraction without a concomitant increase on oxygen consumption. Consequently, the myocardium becomes more efficient pump and is able to meet the demands of circulatory system.
A large number of biologically active compounds are glycosides. Sometimes the glycosidic residue is crucial for their activity, in other cases glycosylation only improves pharmacokinetic parameters. Recent developments in molecular glycobiology brought better understanding of aglycon vs. glycoside activities, and made possible the development of new, more active or more effective glycodrugs based on these findings – a very illustrative recent example is vancomycin. The new enzymatic methodology "glycorandomization" enabled preparation of glycoside libraries and opened up paths to the preparation of optimized or entirely novel glycoside antibiotics. This chapter deals with an array of glycosidic compounds currently used in medicine but also covers the biological activity of some glycosidic metabolites of known drugs.
Except for those mentioned above, there are also othet types like Diagnostic Reagent Series, High Purity Biochemical Reagent, etc.
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