Comparison of Two Methods for Assaying Reducing Sugars in the Determination of Carbohydrase Activities
Table 1
Activities (U/mL or U/g) of different enzyme preparations toward CMC, barley β-glucan, birchwood glucuronoxylan, and galactomannan measured using the DNS and NS assays.
No.
CMCase
β-Glucanase
Xylanase
β-Mannanase
DNS
NS
DNS/NS
DNS
NS
DNS/NS
DNS
NS
DNS/NS*
DNS
NS
DNS/NS
(1)
131
112
1.2
5049
544
9.3
1215
353
3.4 (5.5)
329
36
9.1
(2)
2821
2382
1.2
35624
3051
11.7
8381
2867
2.9 (5.7)
—
—
—
(3)
119
86
1.4
673
79
8.5
345
88
3.9 (8.0)
118
16
7.4
(4)
374
267
1.4
3275
288
11.4
1380
490
2.8 (11.5)
359
40
9.0
(5)
5995
4246
1.4
31915
2628
12.1
3933
1173
3.4 (8.4)
—
—
—
(6)
71
50
1.4
2171
224
9.7
1029
173
5.9 (8.8)
202
33
6.1
(7)
124
83
1.5
692
117
5.9
1694
500
3.4 (5.8)
96
11
8.7
(8)
127
85
1.5
11770
916
12.8
1890
507
3.7 (5.8)
386
76
5.1
(9)
63
41
1.5
636
62
10.3
1379
283
4.9 (8.5)
106
15
7.1
(10)
11755
7607
1.5
71920
6284
11.4
74350
24417
3.0 (11.2)
—
—
—
(11)
9474
5876
1.6
60611
5806
10.4
321904
58600
5.5 (10.4)
982
157
6.3
(12)
132
79
1.7
3591
469
7.7
908
161
5.6 (8.1)
1040
145
7.2
Average ratio
1.4
10.1
4.0 (8.1)
7.3
Std. deviation
0.2
2.0
1.1 (2.1)
1.4
*Ratio of xylanase activities determined with arabinoxylan from wheat as a substrate is given in parentheses.
