The dielectric constant of a solvent is defined as the ratio of the capacitances of a capacitor filled with the solvent or air. Dielectric constant (e) = Csolvent/Cair where C is the capacitance of the condenser filled with respective medium (solvent or air). Every solute shows a maximum solubility in any given solvent system at one…
Lactate, which is produced in the skeletal muscle, is the precursor for gluconeogenesis. In anaerobic conditions, pyruvate is reduced to lactate by using lactate dehydrogenase. Lactate is the end product of glycolysis, since it must be reconverted to pyruvate for its further metabolism. Lactate is carried from the skeletal muscle through blood and handed over…
Cosolvents are used to increase the solubility of weak electrolytes, nonpolar molecules and volatile constituents that are used to impart a desirable flavor and odor to the product. Weak electrolytes and nonpolar molecules have poor water solubility. These types of solutes are more soluble in a mixture of solvents than in one solvent alone. This…
Glucose 6-phosphatase catalyses the conversion of glucose 6-phosphate to glucose. Figure 8.27 Pathway of Gluconeogenesis and Glycolysis in Liver The presence or absence of this enzyme in a tissue determines whether the tissue is capable of contributing glucose to the blood or not. It is mostly present in liver and kidney but not in muscle, brain,…
An excess amount of drug is placed in a vial along with a specific amount of the solvent. The tightly closed vial is then agitated at constant temperature and the amount of drug in solution is determined by a suitable analytical method. The solubility is generally expressed in mg of solute per ml of solvent…
Solubility When a solute is dissolved in a solvent, two types of interactions are possible. One is the intramolecular force of attraction between the solute molecules and the other is the intermolecular force of attraction between the solute and solvent molecules. When a solute dissolves, the intramolecular force or cohesive force must be overcome by…
Phosphoenol pyruvate undergoes the reversal of glycolysis until fructose 1,6-bisphosphate is produced. The enzyme fructose 1,6-bisphosphatase converts fructose 1,6 bisphosphate to fructose 6-phosphate.
Solutions are classified on the basis of the following aspects (Figure 6.1): Figure 6.1 Classification of Monophasic Liquid Dosage Forms
This takes place in two steps. Pyruvate carboxylase is a biotin-dependent mitochondrial enzyme that converts pyruvate to oxaloacetate in the presence of ATP and CO2. This enzyme regulates gluconeogenesis. Oxaloacetate is synthesised in the mitochondrial matrix. It has to be transported to cytosol to be used in gluconeogenesis, where the rest of the pathway occurs.…
Gluconeogenesis closely resembles the reversed pathway of glycolysis, the citric acid cycle, and some special reactions as shown in Figure 8.27. The three stages bypassed by alternate enzymes specific to gluconeogenesis are discussed below: The following are the enzymes involved in gluconeogenesis: