实验纤维素酶活力的测定.docx

实验纤维素酶活力的测定〔3,5-二硝基水酸法〕
一、实验目的
掌握复原糖的测定原理,学习用3,5-二硝基水酸法测定纤维素酶活力的法.
二、实验原理
纤维素酶水解纤维素,产生纤维二糖、葡萄糖等复原糖,能将3,5-二硝基水酸中的硝基

ExperimentalInstrument
25mLcolorimetrictubetype(2).722spectrophotometer
dropper(4)bath(5)pipette(6)electricfurnace
Reagent
3,5-dinitrosalicylicacidsolution:Weigh10g3,5-twonitrosalicylicacid,dissolvedin200mLofdistilledwater,adding20gsodiumhydroxideofanalytically
pure,200gsodiumpotassiumtartrate,addwaterto500mL,,,,layasideaweekbeforeuse.
-sodiumacetatebuffersolution.
%CMC-Naliquid:,
dissolvedinwatertomakeacolloidalsolution,.
:weigh100mganhydrousglucosedriedtoconstantweight,dissolveinwaterto100mL.
Cellulaseliquid:-sodiumacetatebuffersolution,,dilutewith
thebuffersolutiontoscale.
ExperimentalSteps
StandardCurveDrawing:
,,,,,,,,-,boiledinboilingwaterbath10minforcolordeveloping,thencooling,add21mLofdistilled
water,,
opticaldensityasordinate,glucosegnumberasabscissa,todrawthestandard
curve.
SerialNumber
1
2
3
4
5
6
glucosestandardsolution(mL)
0.
0

0



0

Distilledwater(mL)
1.
0

0



0

3,5-dinitrosalicylicacid(mL)
3.
0





ExperimentOperation
Heating10mininboilingwaterbath,dilutewithwatertoscaleaftercooling,shake,colorimetricdetermination
AbsorbanceA550nm
0.
0