Table 1.

Effects of biotransformation on the biological activities of different diterpenes.

Parent Compound	Biotransformation Biocatalyst	Biological Activity Evaluated	Enzymatic Reaction	Effect on Biological Activity *	References
sclareolide	fungi	cytotoxicity in vitro	hydroxylation	enhance	[72]
ingenol-3-angelate	plant cell cultures	cytotoxicity in vitro	Hydroxylation deacylation	decrease decrease	[66]
ent-15α-hydroxy-kaur-16-en-19-oic	fungi	allelopathic	hydroxylation	enhance	[73]
ent-8(14),15-pimaradiene	fungi	antibacterial	hydroxylation dihydroxylation	enhance no effect	[74]
mulin-11,13-dien-20 oic acid	fungi	gastroprotective in vivo	hydroxylation dihydroxylation	enhance enhance	[75]
20-deoxyingenol	fungi	cytotoxicity in vitro	hydroxylation	no effect	[81]
13-oxyingenol dodecanoate	fungi	cytotoxicity in vitro	hydroxylation	decrease	[81]
pseudolaric acid B	fungi	antifungal	conjugation with amino acids epimerization migration of double bond	decrease decrease decrease	[46]
ent-trachyloban-18-oic acid	fungi	cytotoxicity in vitro	hydroxylation backbone rearrangement	decrease decrease	[80]
(+)-(4R,5S,8R,9S)-18-hydroxy-ent-halima-1(10),13-(E)-dien-15-oic	fungi	anticholinesterase (Hr-AChE)	oxidation carboxylation hydroxylation	enhance enhance enhance	[55]
cryptotanshinone	fungi	antiviral	Degradation and rearrangement	enhance	[54]
16-oxacleroda-3,13(14)E-dien-15-oic acid	fungi	antifungal	hydroxylation	enhance	[82]
trachyloban-19-oic acid	fungi	anticholinesterase	oxidation rearrangement	enhance enhance	[65]
10-oxo-2R,5R,14β-triacetox-ytaxa-4(20),11(12)-diene	bacteria	tumor MDR reversal activity	hydroxylation dihydroxylation oxidation and acetalization	no effect no effect enhance	[59]
deoxyandrographolide	fungi	LPS-induced NO production	oxidation of –OH to ketone hydroxylation epoxidation cleavage of the lactone	enhance decrease decrease decrease	[77]
andrographolide	fungi	cytotoxicity in vitro	oxidation of –OH to ketone hydration epimerization	decrease decrease enhance	[56,57]

* When compared to the parent compound.