The Inhibitory Effects of L-Adrenaline on Lactoperoxidase Enzyme Purified from Bovine Milk

Figures & data

Table 1 Purification scheme of LPO obtained after the application of different purification steps

Purification steps	Total volume (mL)	Enzyme activity (EU/mL)	Total enzyme activity (ABTS Unit)	Protein (mg/mL)	Total protein (mg)	Specific activity (EU/mg)	Recovery (%)	Purification fold
Homogenate	185	2.53	468.05	1.73	320.05	1.46	100	1.00
Ammonium sulphate precipitation	35	12.86	450.10	2.09	73.15	6.15	96.19	4.21
CM-Sephadex C-50 column chromatography	302	1.35	407.70	0.095	28.69	14.21	87.1	9.73
Ammonium sulphate precipitation	31	11.43	354.33	0.66	20.46	17.32	75.7	11.86
Sephadex G-100 column chromatography	143	1.96	280.28	0.10	14.30	19.60	59.9	13.42
Ammonium sulphate precipitation and dialyze	31	6.37	197.47	0.21	6.51	30.33	42.18	20.77
LPO: Lactoperoxidase enzyme purified from bovine milk.

Figure 1 Column 1: SDS-PAGE bands of LPO purified from bovine milk. Column 2: standard proteins. Line a: bovine serum albumine (66 kDa). Line b: ovalbumine (45 kDa). LPO: lactoperoxidase; SDS-PAGE: sodium dodecylsulphate-polyacrylamide gel electrophoresis. (Color figure available online.)

Table 2 IC₅₀ values, K _i constant, and inhibition type of L-adrenaline as inhibitor of LPO

	L-Adrenaline
IC50 value (mM)	34.5
Ki constant (μM)	2.26
Inhibition type	Non-competitive
LPO: Lactoperoxidase enzyme purified from bovine milk.

Figure 2 The effect of different concentrations of L-adrenaline (8.33–55.0 mM) on lactoperoxidase obtained from bovine milk (R ²: 0.9984).

Figure 3 Lineweaver-Burk graph for different ABTS concentrations and three different L-adrenaline concentrations for determination of K_i constant.