Anti-TMV activity and functional mechanisms of two sesquiterpenoids isolated from Tithonia diversifolia

Abstract

Unlike chemical pesticides, antiviral plants are biodegradable, replenishable and safe. In this study, 14 sesquiterpene compounds from Tithonia diversifolia were tested for their activities against Tobacco mosaic virus (TMV) using the half-leaf method. Tagitinin C (Ses-2) and 1β-methoxydiversifolin-3-0-methyl ether (Ses-5) were found to have in vivo curative activities of 62.86% and 60.27% respectively, at concentrations of 100μg/mL, respectively. In contrast, the in vivo curative inhibition rate of control agent ningnanmycin was 52.48%. Indirect enzyme-linked immunosorbent assay (ID-ELISA) also verified Ses-2 and Ses-5 had higher inhibition activities than the control agent ningnanmycin. Additionally, qRT-PCR showed that both Ses-2 and Ses-5 can partly inhibit the expression of CP and RdRp, two genes that play key roles in TMV infection. When TMV started to systemically spread, Ses-2 inhibited CP expression while Ses-5 inhibited RdRp expression. These results suggest that the two bio-agents have anti-TMV activities and may be used as bio-pesticides to control the plant virus.

Diterpenoid compounds from Wedelia trilobata induce resistance to Tomato spotted wilt virus via the JA signal pathway in tobacco plants

“…Plant resistance to viruses can be induced by chemicals, such as benzothiadiazole, eugenol, 3-acetonyl-3-hydroxyoxindole (AHO), andsesquiterpenoids 10,12,27,28 . Induced resistance has been shown to be an alternative for managing viral infections of crops 29 .…”

Inhibitory Effect of Osthole from Cnidium monnieri on Tobacco Mosaic Virus (TMV) Infection in Nicotiana glutinosa

“…Many studies have reported the inhibitory effects of plant-derived antiviral pesticides on TMV. Tagitinin C (Ses-2) and 1β-methoxydiversifolin-3-0-methyl ether (Ses-5), two sesquiterpenoids isolated from Tithonia diversiflia, were found to have higher inhibitory activities than the control agent ningnanmycin [16]. Wang et al found that sulfated lentinan induced systemic and long-term protection against TMV in tobacco [17].…”

Synthesis, bioactivity and mode of action of 5A5B6C tricyclic spirolactones as novel antiviral lead compounds

“…Two sesquiterpenoids isolated from Tithonia diversifolia exhibited good curative activities by inhibiting the expression of CP and RNA-dependent RNA polymerase (RdRp). 16 Antofine analogues directly bind with malformed RNA structures to disrupt the interactions between TMV RNA and TMV CP, which severely inhibits virus assembly and systemic infection. 17 RNA silencing also functions as a major natural antiviral defense mechanism in plants.…”

“…In addition to activating the host defense pathway, direct interference with virus proteins was also the main strategy for virus resistance. Two sesquiterpenoids isolated from Tithonia diversifolia exhibited good curative activities by inhibiting the expression of CP and RNA‐dependent RNA polymerase (RdRp) . Antofine analogues directly bind with malformed RNA structures to disrupt the interactions between TMV RNA and TMV CP, which severely inhibits virus assembly and systemic infection .…”