Table 2.

Tyrosinase inhibitory effects of arbutin and α-arbutin and their glucosides.

Literature	Compounds		Tyrosinase Inhibitory Effects		Enzymes and Substrates Used
	Name	Chemical Structure	Monophenolase Activity	Diphenolase Activity
[89]	α-arbutin	3		IC50 = 2.1 mM	Human tyrosinase; 3.3 mM L-DOPA
	Arbutin	2		IC50 > 30 mM
	4-Hydroxyphenyl β-maltoside	7		IC50 = 5.7 mM
	4-Hydroxyphenyl β-maltotrioside	8		IC50 = 6.1 mM
[90]	4-Hydroxyphenyl α-maltoside	11		IC50 = 4.9 mM	Human tyrosinase; 3.3 mM L-DOPA
	4-Hydroxyphenyl α-maltotrioside	12		IC50 = 13.9 mM
[91]	Arbutin	2		Ki = 2.8 mM	Mushroom tyrosinase; 3.3 mM DOPA
	4-Hydroxyphenyl β-isomaltoside	9		Ki = 3.7 mM
	4-Hydroxyphenyl β-isomaltotrioside	10		Not determined
[92]	Arbutin	2	IC50 = 6 mM		Mushroom tyrosinase; 0.03% L-tyrosine
	β-D-Glucopyranosyl-(1→6)-arbutin	4	IC50 = 8 mM
	β-D-Glucopyranosyl-(1→4)-arbutin	5	IC50 = 10 mM
	β-D-Glucopyranosyl-(1→3)-arbutin	6	IC50 = 5 mM
	α-D-Glucopyranosyl-(1→4)-arbutin	7	IC50 = 5 mM
[93]	α-arbutin	3		IC50 = 2.1 mM	Human tyrosinase; 3 mM L-DOPA
	α-arbutin-α-glucoside	11		IC50 = 6.9 mM
	α-arbutin-α-maltoside	12		IC50 = 15.6 mM
	α-arbutin-α-maltotrioside	13		Not determined