Table 2.

Major functional groups of active components based on the peak value of Fourier transform infrared.

Seaweed species	Extracts	Major functional groups
		Phenol	Carboxylic acids	Alkoxy	Aromatics	Alkene	Amides/amines	Sulfonate
P. tetrastromatica	Methanol	$+$	$+$	$+$	$-$	$+$	$-$	$+$
	Ethanol	$+$	$+$	$+$	$+$	$+$	$-$	$+$
	Water	$+$	$+$	$+$	$+$	$+$	$+$	$-$
G. tenuistipitata	Methanol	$+$	$+$	$+$	$+$	$+$	$-$	$+$
	Ethanol	$+$	$+$	$+$	$+$	$+$	$+$	$-$
	Water	$+$	$+$	$+$	$+$	$+$	$+$	$-$

“+” constituent's existence, “−” constituent's non-existence.