Inhibition of Herpes Simplex Virus Type 1 by Thymol-Related Monoterpenoids

Lai, Wen-Lin; Chuang, He-Shing; Lee, Meng-Hwan; Wei, Chia-Li; Lin, Chin-Fu; Tsai, Ying-Chieh

doi:10.1055/s-0032-1315208

Cited by 71 publications

(59 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A novel finding is the anti‐HSV‐2 activity of cinnamaldehyde (SI: 28.3) reported here for the first time. Finally, the anti‐HSV‐2 activity of carvacrol (SI: 12.1) confirmed previous findings by Pilau et al () and Lai et al (). As shown in Figure , carvacrol and cinnamaldehyde were also found as components of the EO; however, this was not the most active phytopreparation.…”

Section: Resultssupporting

confidence: 90%

Inhibition of HSV‐2 infection by pure compounds from Thymus capitatus extract in vitro

Toujani

Rittá

Civra

et al. 2018

Phytotherapy Research

View full text Add to dashboard Cite

Thymus capitatus represents 1 of the 5 Tunisian species of the genus Thymus, which has long‐standing use for flavouring and preserving several food products. Its constituents have been reported to endow antimicrobial properties, but little is known about their antiviral activities. The aim of this study was to examine the antiviral activity of pure compounds from the most bioactive inhibitory T. capitatus extract in vitro against herpes simplex virus Type 2 (HSV‐2) infection and to identify their mechanism of action. Either the extracts or the essential oil exert inhibitory activity against HSV‐2 infection, with the ethanolic extract showing the lowest EC50 value (2.3 μg/ml). Three pure compounds were then isolated from the ethanolic extract and investigated for their antiviral activity. β‐sitosterol showed the most favourable selectivity index and both cinnamaldehyde and carvacrol exerted moderate antiviral effect. Investigation of the mechanism of action revealed that all three compounds directly inactivated the infectivity of the virus particles. These findings suggest the use of T. capitatus ethanolic extract as source of anti‐HSV‐2 pure compounds and warrant further studies to evaluate their therapeutic potential.

show abstract

Section: Resultssupporting

confidence: 90%

Inhibition of HSV‐2 infection by pure compounds from Thymus capitatus extract in vitro

Toujani

Rittá

Civra

et al. 2018

Phytotherapy Research

View full text Add to dashboard Cite

show abstract

“…Lai et al . reported disruption of the envelope of HSV‐1 (as visualized via TEM) by carvacrol and thymol. Another study reported the disintegration of the envelopes of HSV‐1 and Newcastle disease virus after treatment with oregano and clove oils using TEM imaging (Siddiqui et al .…”

Section: Discussionmentioning

confidence: 99%

Antiviral efficacy and mechanisms of action of oregano essential oil and its primary component carvacrol against murine norovirus

et al. 2014

View full text Add to dashboard Cite

Aims: To investigate the antiviral efficacy of oregano oil and its primary active component, carvacrol, against the nonenveloped murine norovirus (MNV), a human norovirus surrogate. Methods and Results: Along with an observed loss in cell culture infectivity, the antiviral mechanisms of action were determined in side-by-side experiments including a cell-binding assay, an RNase I protection assay and transmission electron microscopy (TEM). Both antimicrobials produced statistically significant reductions (P ≤ 0Á05) in virus infectivity within 15 min of exposure (c. 1Á0-log 10 ). Despite this, the MNV infectivity remained stable with increasing time exposure to oregano oil (1Á07-log 10 after 24 h), while carvacrol was far more effective, producing up to 3Á87-log 10 reductions within 1 h. Based on the RNase I protection assay, both antimicrobials appeared to act directly upon the virus capsid and subsequently the RNA. Under TEM, the capsids enlarged from ≤35 nm in diameter to up to 75 nm following treatment with oregano oil and up to 800 nm with carvacrol; with greater expansion, capsid disintegration could be observed. Virus adsorption to host cells did not appear to be affected by either antimicrobial.Conclusions: Our results demonstrate that carvacrol is effective in inactivating MNV within 1 h of exposure by acting directly on the viral capsid and subsequently the RNA. Significance and Impact of the Study: This study provides novel findings on the antiviral properties of oregano oil and carvacrol against MNV and demonstrates the potential of carvacrol as a natural food and surface (fomite) sanitizer to control human norovirus.

show abstract

“…Wen et al (90) found that two phytocompounds, betulinic acid and savinin, appeared to inhibit postbinding entry of severe acute respiratory syndrome (SARS) coronavirus into cells. Evidence from TEM imaging indicates that some plant antimicrobials may act directly upon the virus envelope (50,53,63).…”

Section: Discussionmentioning

confidence: 99%

“…Many plant essential oils, extracts, and their individual components have been shown to possess antibacterial properties in previous studies (30,34,35,36,37,38,39,40,41). Some have also been shown to have antifungal (30,42,43,44,45) and antiviral (30,46,47,48,49,50,51,52,53,54) properties.…”

mentioning

confidence: 97%

“…The majority of such antiviral research has been directed toward clinically relevant enveloped viruses (30,39,47,51,54,55,56,57,58,59,60,61,62), such as herpes simplex virus 1 (HSV-1) (48,52,53) and influenza A virus (46,49,50), with only limited work performed using nonenveloped viruses such as NoV. A few studies have compared the antiviral efficacies of plant antimicrobials with both enveloped and nonenveloped viruses. The observed antiviral effect has usually been greater for enveloped viruses.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Mechanisms of Antiviral Action of Plant Antimicrobials against Murine Norovirus

Gilling

Kitajima

Torrey

et al. 2014

Appl Environ Microbiol

View full text Add to dashboard Cite

Numerous plant compounds have antibacterial or antiviral properties; however, limited research has been conducted with nonenveloped viruses. The efficacies of allspice oil, lemongrass oil, and citral were evaluated against the nonenveloped murine norovirus (MNV), a human norovirus surrogate. The antiviral mechanisms of action were also examined using an RNase I protection assay, a host cell binding assay, and transmission electron microscopy. All three antimicrobials produced significant reductions (P < 0.05) in viral infectivity within 6 h of exposure (0.90 log 10 to 1.88 log 10 ). After 24 h, the reductions were 2.74, 3.00, and 3.41 log 10 for lemongrass oil, citral, and allspice oil, respectively. The antiviral effect of allspice oil was both time and concentration dependent; the effects of lemongrass oil and citral were time dependent. Based on the RNase I assay, allspice oil appeared to act directly upon the viral capsid and RNA. The capsids enlarged from <35 nm to up to 75 nm following treatment. MNV adsorption to host cells was not significantly affected. Alternatively, the capsid remained intact following exposure to lemongrass oil and citral, which appeared to coat the capsid, causing nonspecific and nonproductive binding to host cells that did not lead to successful infection. Such contrasting effects between allspice oil and both lemongrass oil and citral suggest that though different plant compounds may yield similar reductions in virus infectivity, the mechanisms of inactivation may be highly varied and specific to the antimicrobial. This study demonstrates the antiviral properties of allspice oil, lemongrass oil, and citral against MNV and thus indicates their potential as natural food and surface sanitizers to control noroviruses.

show abstract

Inhibition of Herpes Simplex Virus Type 1 by Thymol-Related Monoterpenoids

Cited by 71 publications

References 10 publications

Inhibition of HSV‐2 infection by pure compounds from Thymus capitatus extract in vitro

Inhibition of HSV‐2 infection by pure compounds from Thymus capitatus extract in vitro

Antiviral efficacy and mechanisms of action of oregano essential oil and its primary component carvacrol against murine norovirus

Mechanisms of Antiviral Action of Plant Antimicrobials against Murine Norovirus

Contact Info

Product

Resources

About