The method of determining the activity of lipase.

: Ask you about the determination method of lipase vitality, instruments,
reagents
. Thank you for your advice!
: That's what I found in a piece of literature. The acid price is used as an indicator, 95% ethanol is used as a terminator, and the determination of acid price reflects the degree to which lipase breaks down fat, so as to find enzyme vitality.
:
1, preparation of crude enzyme fluid
in use of electrons
balance
respectively called crude lipase 0.010 g, 0.020 g and 0.030 g, Dissolved with distilled water and fixed to 100 mL, with concentrations of 0.01%, 0.02% and 0.03%, respectively.
2, experimental design
This experiment with 10 mL salad oil as the base, with enzyme dosing, hydrolytic temperature, reaction time factors, through the determination of acid price to determine the best conditions for hydrolyzing.
3, acid price measurement
acid price refers to the number of milligrams of NaOH required to medium 1 mol free fatty acids, which is used to measure the degree of hydrolysing of fats and fats. In the experiment,
the acid price
hydrolytes was determined by titration of acid and alkali. Referring to the method used in the literature, add 1 mL 95% ethanol solution to the resulting hydrolyte droplets, shake well, terminate the reaction, and add 2 drops of phenolic indicator, quickly titration the solution with 0.05 mol/L NaOH solution to the solution is slightly red, does not disappear within 30 s for the end point, records the consumption of NaOH solution ml (V). The blank values are measured in the same way, repeated twice per experiment, with the average as the result.
the acid price press calculation:
. X - C (V - V0) ×40 / M
: X - Grease acid price (mgNaOH /g oil)
C - NaOH standard solution concentration (mol/L)
M - sample mass (g)
40- NaOH's mmol mass (mg/mmol)
4 determination of crude lipase vitality
Under optimal hydrolytic conditions, the acid price of crude lipase and standard lipase hydrolytes was measured X1, X2, respectively, according to formula U1 / U - X1 / X2 to find the vitality of crude lipase, Where U1 is crude lipase vitality, U is standard lipase vitality.
5 standard lipase solution is
according to the best conditions of the experiment, the preparation of standard lipase solution.
: Experimental design, this experiment with 10 mL salad oil as the base, with enzyme dosing, hydrolytic temperature, reaction time factors, through the determination of acid price to select the best conditions for hydrolyzing. It is not appropriate to use salad oil as a base, generally olive oil, chemical pure.
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