Potential roles of medicinal plants for the treatment of viral diseases focusing on COVID-19: A review

Abstract

The whole world is entangled by the coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), people are dying in thousands each day, and without an actual medication, it seems not possible for the bringing this global health crisis to a stop. Natural products have been in constant use since ancient times and are proven by time to be effective. Crude extract or pure compounds isolated from medicinal plants and/or herbs such as Artemisia annua, Agastache rugosa, Astragalus membranaceus, Cassia alata, Ecklonia cava, Gymnema sylvestre, Glycyrrhizae uralensis, Houttuynia cordata, Lindera aggregata, Lycoris radiata, Mollugo cerviana, Polygonum multiflorum, Pyrrosia lingua, Saposhnikoviae divaricate, Tinospora cordifolia etc. have shown promising inhibitory effect against coronavirus. Several molecules, including acacetin, amentoflavone, allicin, blancoxanthone, curcumin, daidzein, diosmin, epigallocatechin-gallate, emodin, hesperidin, herbacetin, hirsutenone, iguesterin, jubanine G, kaempferol, lycorine, pectolinarin, phloroeckol, silvestrol, tanshinone I, taxifolin, rhoifolin, xanthoangelol E, zingerol etc. isolated from plants could also be potential drug candidates against COVID-19. Moreover, these could also show promising inhibitory effects against influenza-parainfluenza viruses, respiratory syncytial virus, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome coronavirus (MERS-CoV). Here, we have reported 93 antiviral drug candidates which could be a potential area of research in drug discovery.

Keywords: anti-antiviral activity and COVID-19; drug candidates; natural products.

FIGURE 1

Multliplication stages of virus in a living cell and major antiviral drugs with their mode of action http://biorender.com [Colour figure can be viewed at wileyonlinelibrary.com]

FIGURE 2

(a) Natural compounds isolated from medicinal plants for antiviral activity: Lycorine (1), Kaempferol (2), Quercetin (3), Luteolin‐7‐glucoside (4), Demethoxycurcumin (5), Naringenin (6), Apigenin‐7‐glucoside (7), Oleuropein (8), Curcumin (9), Catechin (10), Epigallocatechin‐gallate (11), Zingerol (12), Gingerol (13), Allicin (14), Hesperidin (15),Diammonium glycyrrhizinate (16). (b) Natural compounds isolated from medicinal plants for antiviral activity: Amentoflavone (17), Betulinic acid (18), Bisbenzylisoquinoline (19), Blancoxanthone (20), Chrysanthemumin B (21), Cryptotanshinone (22), Escinidin (23), Hirsutenone (24), Homoharringtonine (25), Iguesterin (26), Jubanine G (27), Kazinol F (28), Leptodactylone (29), Ouabain (30), Psoralidin (31), Papyriflavonol A (32). (c) Natural compounds isolated from medicinal plants for antiviral activity: Schimperinone (33), Silvestrol (34), Sinigrin (35), Tanshinone I (36), Theaflavin (37), Tingenone (38), Tylophorine (39), Xanthoangelol E (40), 7‐Methoxycryptopleurine (41). (d) Natural compounds isolated from medicinal plants for antiviral activity: Friedeline (42), Methyl‐3α,23‐dihydroxy‐17,14‐friedolanstan‐8,14,24‐trien‐26‐oat (43), 24E‐3a,9,23‐trihydroxy‐17,14‐ friedolanostan‐14,24‐dien‐26‐oate (44), Pentagalloylglucose (PGG) (45), Glycyrrhizic acid (46), 2‐Acetamido‐β‐D‐glucopyansylamine (47), Acacetin (48), Auraptene (49), Cardamonin (50), Daidzein (51), Epicatechin (52), Glabridin (53), Herbacetin (54), Isoxanthohumol (55), Taxifolin hydrate (56), Isobavachalcone (57), Quercetin 3‐β‐D‐glucoside (58). (e) Natural compounds isolated from medicinal plants for antiviral activity: Helichrysetin (59), Fisetin (60), Rutin (61), Coumarin (62), Caffeic acid (63), 5‐Caffeoylquinic acid (64), Calanolide A (65), Baicalin (66), Emodin (67), Pectolinarin (68), Cannabinoids (69), Rhoifolin (70), Diosmin (71), Apiin (72), Diacetylcurcumin (73). (f) Natural compounds isolated from medicinal plants for antiviral activity: (E)‐1‐(2‐Hydroxy‐4‐methoxyphenyl)‐3‐[3‐[(E)‐3‐(2‐hydroxy‐4‐methoxyphenyl)‐3‐oxoprop‐1‐enyl]phenyl]prop‐2‐en‐1‐one (74), beta,beta′‐(4‐Methoxy‐1,3‐phenylene)bis(2′‐hydroxy‐4′,6′‐dimethoxyacrylophenone (75), Isoscutellarein (76), 5,7‐Dimethoxyflavone (77), Tetramethyllueteonin (78), Tri methyl apigenin (79),5‐Hydroxy‐7‐methoxyflavone (80), Ginkgetin (81), Quercetin 3‐rhamnoside (82), Celastrol (83), Pristimerin (84), Tingenone (85). (g) Natural compounds isolated from medicinal plants for antiviral activity: Dieckol (86), Eckol (87), Triphloretol A (88), Dioxinodehydroeckol (89), 2‐Phloroeckol (90), 7‐Phloroeckol (91), Phlorofucofuroeckol A (92), Fucodiphloroethol G (93)