All rights reserved. Terms of use. Â¨ 37 11 Thermodynamics andThermochemistry Thermodynamics is the study of heat, and how heat can be interconverted into other energyforms. In thermodynamics the system is a specific part of the universe that is being studied,often the system is a chemical reaction. The surroundings are all parts of the universe that arenot the system, typically everything outside the test tube.Â¥ An open system can exchange both energy and matter with its surroundings.
Pepsin splits proteins into water-soluble fragments called peptones. Although this ordinarily occurs in the stomach, it can be duplicated in a large reaction vessel on a commercial basis. Partial digestion by pepsin can be used in food applicationsâfor instance, in the processing of soy protein and gelatin.
7 For general digestion of proteins, suggestedconditions are a 0.4% solution of pepsin in10 mM HCl, and digestion for 30-90 minutes at 37 Â°C.Pepsin has optimal activity with native proteins atapproximately pH 1.0, but with some denaturedproteins the optimal activity is at approximatelypH 1.5-3.5. For general digestion of proteins, suggestedconditions are a 0.4% solution of pepsin in10 mM HCl, and digestion for 30-90 minutes at 37 Â°C.Pepsin has optimal activity with native proteins atapproximately pH 1.0, but with some denaturedproteins the optimal activity is at approximatelypH 1.5-3.5.