Table 2.

Algal compounds prevent the entrance of viruses into the body.

Mode of entry	Compound	Species classification	Species	Model	Virus	Reference
Respiratory epithelia	Carrageenan	Rhodophyta	Not reported	Clinical trials, murine	CoV IAV PIAV MPNV RSV RHV	[[45], [46], [47], [48]]
	Fucoidan	Phaeophyceae	Kjellmaniella crassifolia	Murine	IAV-A	[49]
Alimentary epithelia	Fucoidan	Phaeophyceae	Undaria pinnatifida	Murine	IAV-A Avian IAV-A	[58,59,61]
Urogenital epithelia	Carrageenan	Rhodophyta	Not reported	Clinical trial Rhesus macaque	HPV HIV HSV-2 Simian immunodeficiency virus (SIV) HIV HPV	[53,54] [55] [56] [57]
	Lectins	Assorted algae, cyanobacteria Rhodophyta	Various Originally isolated from Griffithsia sp., produced recombinantly in Nicotiana benthamiana (Solanaceae)	In vitro In vitro; TZM-bl, HeLa, Vero	HIV HSV-2, HPV	[58] [59]
	MGDG	Chlorophyta	Coccomyxa sp.	Murine	HSV-2	[60]
Dermal lesion	Diterpenes	Phaeophyceae	Canistrocarpus cervicornis	Murine	HSV-1	[65]
	Bromophenols	Rhodophyta	Symphyocladia latiuscula	Murine	HSV-1	[62]
	Protein extract	Phaeophyceae	Macrocystis pyrifera, Durvillaea antarctica	Murine	HSV-1, HSV-2	[63]
	PMG	Phaeophyceae	Not reported	Murine	HPV	[64]
Conjunctiva	Carrageenan	Rhodophyceae	Not reported	Feline	FHV-1	[65]