Medicinal Plants with Antiviral Properties to Tackle Covid-19 Pandemic: A Short-Review

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Citation:
Sadeek AM, Abdallah EM (2021). Medicinal Plants with Antiviral Properties to Tackle Covid-19 Pandemic: A Short-Review.
SunText Rev Biotechnol 2(1): 122.
1
SunText Review of Biotechnology Open Access
ISSN: 2766-5097 Review Article
Volume 2:1
Medicinal Plants with Antiviral Properties to
Tackle Covid-19 Pandemic: A Short-Review
Sadeek AM and Abdallah EM*
Department of Laboratory Sciences, College of Science and Arts at Al Rass, Qassim
University, Saudi Arabia
*Corresponding author: Abdallah EM, Department of Laboratory Sciences, College of Science
and Arts at Al Rass, Qassim University, Saudi Arabia; Email: emad100sdl@yahoo.com
Abstract
The dramatic spread of the new coronavirus (SARS-CoV-2) abbreviated as COVID-19 is considered the worst disaster for humanity
in the 21st century. Extensive reports have been published since this pandemic was announced in December 2019. Regardless of the
effectiveness of some vaccines that have been appeared the human body can be supported with some bioactive natural products and
medicinal plants that may combat this coronavirus, reduce its deadly risks and even provide complete treatment. The future endeavors
face many challenges as medicinal plant drug discovery has historically taken slower and more complex than most synthetic or
chemical drugs. Therefore, faster and better methodologies must be employed. Interestingly, phytochemical molecules of antiviral
activity extracted from medicinal plants have been reported as possible therapeutic agents in the treatment of COVID-19 disease,
thereby warranting further comprehensive investigation. The current short-review aimed to highlight some medicinal plants of
potential antiviral activity for extensive studies against SARS-CoV-2 virus causing COVID-19 disease and called to revisit and
retrieve the interest in medicinal plants as possible anti-covid-19 agents and as a potential renewable source for antiviral drugs.
Keywords: Coronavirus; Covid-19; SARS-CoV-2; Medicinal plants
Introduction
At the beginning of the year 2020, the world faced a health
catastrophe that had not been seen in centuries, named the Covid-
19 pandemic. This epidemic has changed people's lifestyle all
over the globe; social distancing, use of gloves, masks, and hand
sanitizer have become daily human behaviors, millions of people
have been put on lockdown, flights and transportation have been
closed, and economic activities have been stopped which causes
extensive job losses there is a direct loss to the world economy
[1,2]. To date, more than 2,317,162 people have died across the
world and the number of global positive cases overflow106
million; it is anticipated that cases would rise gradually, at least in
the coming months [3]. All of this helps one consider a serious
question, which is: Have we mishandled or misjudge this
pandemic. To answer this substantial question, we must first
clarify the unsuccessful measures that have been introduced and
have no scientific basis, and have proven to be ineffective [4].
Summarized them into five measures:
1. The air disinfection of cities and communities,
2. The excessive usage of personal protective equipment,
3. The blind practice of blocking life activities and lockdown
of cities and villages,
4. The spread of misinformation that leads to the expansion of
panic, anxiety, and fear.
5. Growing and circulating the concept that there is no
effective cure or drug to tackle Covid-19.
The author believes that the fifth misleading measure must be
resisted with extensive scientific research on the possible sources
for antiviral-remedies, Parallel to the efforts made to create
effective vaccines. Medicinal plants and natural products were the
largest renewable source of medication since ancient times and
still is until now, and numerous plant extracts that exhibited
remarkable antiviral activities have been reported in the literature,
Received date: 02 April 2021; Accepted date: 14
April 2021; Published date: 29 April 2021
Citation: Sadeek AM, Abdallah EM (2021).
Medicinal Plants with Antiviral Properties to Tackle
Covid-19 Pandemic: A Short-Review. SunText Rev
Biotechnol 2(1): 122.
DOI: https://doi.org/10.51737/2766-5097.2021.022
Copyright: © 2021 Abdallah EM. This is an open-
access article distributed under the terms of the
Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are
credited.

Sadeek, SunText Rev Biotechnol (2021), 2:1
Citation:
Sadeek AM, Abdallah EM (2021). Medicinal Plants with Antiviral Properties to Tackle Covid-19 Pandemic: A Short-Review.
SunText Rev Biotechnol 2(1): 122.
deserve to be investigated and evaluated against the SARS-Cov-2
virus. The current mini-review aims to highlight and suggest
some antiviral medicinal plants for urgent scientific investigations
to tackle the Covid-19 pandemic [5].
SARS-Cov-2 Infection and Treatment
The SARS-CoV-2 virus that causing COVID-19 disease was
initially reported in Wuhan, China on 30 December 2019, it is a
new human coronavirus candidate belongs to the family
Coronaviridae; a diverse group of viruses that are mostly zoonotic
and rarely infect human, approximately four coronaviruses were
known to infect human and causing mild-symptoms of common
cold or flu and mostly recovered in a short period without
noticeable complications, these four infectious coronaviruses are
HCoVOC43, HCoV-229E, HCoV-UKU1, and HCoV-NL63 [6].
Notably, coronaviruses had caused pandemics since the start of
the new millennium, two highly pathogenic coronaviruses have
emerged, severe acute respiratory syndrome coronavirus (SARS-
CoV) in 2002 and Middle East respiratory syndrome coronavirus
(MERS-CoV) in 2012 [7, 8]. Although, the last one that appeared
at the end of 2019 (SARS-CoV-2) is the most devastating yet.
Although the fatality ratio is of SARS-CoV-2 (2.3%) is less than
that of previous contagious coronaviruses (SARS-CoV fatality
rate = 9.5% and MERS-CoV fatality rate = 34.4% %), and it was
estimated that the average mortality rate from covid-19 was
0.66%, in people over 80 years of age rose dramatically to 7.8%
and declined to 0.0016% in children aged 9 and under However,
the novel coronavirus SARS-CoV-2 (COVID-19) exhibited a
higher reproductive number (R0), which was (2.0–2.5) compared
to the R0 of SARS (1.7–1.9) and the R0 of MERS (<1) [[9,10].
Regretfully, the number of deaths from COVID-19 is much
higher than that of SARS and MERS and the number of
confirmed cases is dramatically increasing every day amongst
some countries Whatever the case, the With respect to the
treatment and prevention, although previous trials have indicated
that some antivirals, including oseltamivir, remdesivir,
lopinavir/ritonavir, and even chloroquine, have been used for
SARS and MERS, so far no adequate clinical trial results are
available [11] (Figure 1).
Some scientists believed that we should apply the “One Health”
approach in our struggle with COVID-19, which national and
global levels for a collective, multisectoral and transdisciplinary
approach to achieve optimum health outcomes against the disease
(Mushi, 2020). Moreover, Scientists believed that vaccination is
one of the most promising options to combat this disease, and
accordingly, seven strategies have been explored as vaccines for
COVID-19; Inactivated virus vaccines, Virus-like particle or
nanoparticle vaccines, Protein subunit vaccines, Virus-vectored
vaccines, Live-attenuated virus vaccines, DNA vaccines, and
mRNA vaccines [12]. As 2020 draws to a close, the acceptance
by the regulatory FDA of COVID-19 vaccines has raised
expectations and ambitions that the pandemic will be eliminated
from our world by the end of 2021.
Figure 1: Distribution of COVID-19 cases in top 7 most affected
countries.
However, the issue of vaccine production and delivery suggests
that could beat the COVID-19 pandemic would be a long-winded
marathon whose finish line is still far from being realized [13].
For all these attempts to counter COVID-19, the main source,
which is medicinal plants, is ignored for all prescription
medicines over the centuries.
Medicinal Plants of Antiviral Activity
It is ironic that plants were the main source of medicines and
drugs throughout the ages and ancient civilizations, but they were
so far neglected in modern civilization represented by the largest
global pharmaceutical companies that turned to synthetic
chemical compositions. Whereas, the WHO estimated that more
than 80% of Earth's population relied on traditional medicine in
their primary health care and that traditional medicine mostly
depended on medicinal plants [14]. Since viruses occur before the
advent of man on Earth, and man used to treat them with
medicinal plants in the ages before Dmitri Ivanovsky discovered
them in1892. It is also clear that certain active compounds that are
capable of defending against or destroying viruses can be found in
medicinal plants. It is estimated that antiviral plant molecules
undergo action by various mechanisms, such as inactivation of
virus particles, reduction of endocytic activity, inhibition of viral
enzymes and the viral molecular reproduction mechanisms,
altering properties of virus capsid, acting as blocking agent during
adsorption and penetration of virus on target human cell,
inhibition of reverse transcriptase process, inhibition of
translational process, decrease in expression level, and inhibiting
viral assembly [15]. Interestingly, China, from which the

Sadeek, SunText Rev Biotechnol (2021), 2:1
Citation:
Sadeek AM, Abdallah EM (2021). Medicinal Plants with Antiviral Properties to Tackle Covid-19 Pandemic: A Short-Review.
SunText Rev Biotechnol 2(1): 122.
epidemic began, exceedingly prevailed over the pandemic, so is
the reason due to their use of Traditional Chinese Medicine in the
treatment of COVID-19. In literature, numerous studies suggested
some herbs and plant products as a potential source for antiviral
drugs, such plants are strongly recommended for scientific
research on SARS-Cov-2 causing COVID-19. In the current
study, some plants of interesting antiviral activity are presented in
and some important phytochemical molecules of potential
antiviral activity are demonstrated in (Figure 2).
Figure 2: Phytochemical molecules of potential antiviral activity.
Up to 16 plant species were mentioned in, which reported a
remarkable antiviral activity, to name but a few. Has published
that garlic exhibited good antiviral activity (Table 1) [16]. Since
ancient times, garlic is used to treat the common cold, this study
showed that some bioactive compounds extracted from garlic
such as allicin, diallyl trisulfide, and ajoene have antiviral
activity, have examined up to 44 Chinese medicinal herbs against
the respiratory syncytial virus (RSV), amongst the twenty-seven
herbs that showed various antiviral activity, Sophora flavescens
Ait [17]. And Scutellaria baicalensis Georgi. Recorded the
highest antiviral potential and recommended as a promising drug.
Nigella sativa (Black seed) is a natural product with various
pharmacological activities, the essential oil of Nigella sativa
represented remarkable antiviral potential against avian influenza
virus (H9N2) and murine cytomegalovirus infection (MCMV)
[18]. Fresh juice (but not dried) of ginger (Zingiber officinale
Rosc.) exhibited high antiviral activity against human respiratory
syncytial virus HRSV-induced, it decreased the numbers of viral
plaques in vitro and blocked viral attachment and internalization
[19]. Aqueous extract of Curcuma longa Linn recorded interested
antiviral effects against hepatitis B virus (HBV), it suppressed the
production of HBV particles and inhibits HBV replication in
HepG 2.2.15 cells [20]. The Purple coneflower (Echinacea
purpurea L.) is a popular herbal medicine in Europe and North
America, consumed as teas, sprays, extracts, and tinctures,
ancient native Americans used it for the treatment of respiratory
infections, studies reported that it has immunostimulatory effects
and antiviral activity against Herpes simplex virus (HSV),
influenza viruses, and respiratory syncytial virus (RSV) [21].
Interestingly, After the SARS coronavirus outbreak in 2002, the
antiviral potential of Artemisia annua was evaluated by some
researchers and the results revealed that its ethanolic extract has a
high antiviral effect against SARS and recommend it as an
effective treatment from SARS [22]. The Hartwood of
Caesalpinia sappan, commonly known as Sappan wood was
found to be active against influenza A virus subtypes H1N1,
H3N2, and H9N2 [23]. Pseudorabies virus (PRV) is a causative
agent of Aujeszky’s disease, a Chinese herb named Radix isatidis
has been recommended as a potent antiviral against that disease
[24]. Leaves Psidium guajava of slowed markedly higher anti-
influenza activities against clinical influenza A (H1N1) [25].
Taraxacum officinale, grown in Mexico, efficiently inhibited the
replication of Dengue virus 2 and subsequent biological analysis
of the bioactive molecules would be performed to develop
therapeutics against Dengue virus 2 (DENV2) [26]. The crude
extract of Capsicum annuum was active against the Herpes
simplex virus and showed low cytotoxicity which can be utilized
to treat herpes infection in conjunction with the regular
medication [27]. The aqueous extract of a Chinese herb,
Houttuynia cordata represented significant immunomodulatory
and anti-SARS activities and results suggested that this antiviral
plant may inhibit the pivotal enzymes which lead to slow down
the viral replication process and accordingly trigger negative
feedback control in the immune system [28].
The activity of protocatechuic acid extracted from Hibiscus
sabdariffa was examined against Herpes simplex virus 2 (HSV-
2), the protocatechuic acid exhibits potent anti-HSV-2 activity
compared to that of acyclovir drug [29]. A Controversial
homeopathic drug derived from an Indian plant known as
Arsenicum album is recommended as an anti-COVID-19 drug by
some scientific reports, and believed that it is effective against
SARS-CoV-2 (COVID-19) and it has an immune-modulator
effect, however, its effectiveness and possible negative symptoms
such as toxicity should be extensively studied due to suspicion of
potential toxicity [30].

Sadeek, SunText Rev Biotechnol (2021), 2:1
Citation:
Sadeek AM, Abdallah EM (2021). Medicinal Plants with Antiviral Properties to Tackle Covid-19 Pandemic: A Short-Review.
SunText Rev Biotechnol 2(1): 122.
Table 1: Some plant species used for the treatment of different viral infections.
Plant name
Common name (s)
Part used
Extract or major
active compound (s)
Effective against virus
Reference
Allium sativum
Garlic
Bulb
Allicin, diallyl
trisulfide and ajoene
Influenza A and B,
cytomegalovirus,
rhinovirus, HIV, herpes
simplex virus herpes
simplex virus 2 viral
pneumonia, and
rotavirus.
[16]
Sophora
flavescens
Scutellaria
baicalensis
Ku Shen (bitter
root)
Baikal skullcap
(Chinese skullcap)
Root
Root
Anagyrine, oxymatrine,
sophoranol, wogonin,
and oroxylin A.
Respiratory syncytial
virus (RSV) also called
human respiratory
syncytial virus (HRSV)
[17]
Nigella sativa
Black cumin
Seeds
Thymoquinones
Avian influenza virus
(H9N2) and murine
cytomegalovirus
infection (MCMV)
[18]
Zingiber
officinale
Ginger
Rhizomes
Only fresh juice were
active, it is rich in
phytochemical
molecules such as
alkaloids, saponins,
flavonoids,
polyphenols and
cardiac glycosides
Human respiratory
syncytial virus (HRSV)
also called Respiratory
syncytial virus (RSV)
[19]
Curcuma longa
Curcumin
Rhizomes
Aqueous extract of
have antiviral activity,
major compound is
turmeric
hepatitis B virus (HBV)
[20]
Echinacea
purpurea
Purple coneflower,
hedgehog
Areal parts
Chicoric acid, caffeic
acids, alkylamides, and
polysaccharides
Herpes simplex virus
(HSV), influenza
viruses, and
respiratory syncytial
virus (RSV)
[21]
Artemisia annua
Sweet wormwood,
sweet annie
Whole plant
Artemisinin
Severe Acute
Respiratory Syndrome
virus (SARS-CoV)
[22]

Sadeek, SunText Rev Biotechnol (2021), 2:1
Citation:
Sadeek AM, Abdallah EM (2021). Medicinal Plants with Antiviral Properties to Tackle Covid-19 Pandemic: A Short-Review.
SunText Rev Biotechnol 2(1): 122.
Caesalpinia
sappan
Sappan Wood
Heartwood
7,4'-Homoisoflavane
influenza A virus
subtypes H1N1, H3N2,
and H9N2
[23]
Radix isatidis
Ban-Lan-Gen
Roots
Polysaccharides
Pseudorabies virus
(PRV)
[24]
Psidium guajava
Guava
Leaves
Tannins
Influenza A (H1N1)
[25]
Taraxacum
officinale
Dandelion
Leaves
Phenolics
Dengue virus 2
(DENV2)
[26]
Capsicum
annuum
Cayenne pepper
Fruits
Polyphenolics and
flavonoids
Herpes simplex virus
(HSV-1 and HSV-2)
[27]
Houttuynia
cordata
Fish mint, fish leaf,
Chinese lizard tail,
Undefined
Flavonoids,
polyphenols, and
alkaloids.
Severe Acute
Respiratory Syndrome
(SARS)
[28]
Hibiscus
sabdariffa
Roselle
Calyces
Protocatechuic acid
Herpes simplex virus 2
(HSV-2),
[29]
Arsenicum album
Undefined
Undefined
Arsenic
SARS-CoV-2 (COVID-
19)
[30]
Conclusions
Three highly pathogenic and virulent human coronaviruses have
arisen within the last two decades, namely SARS, MERS, and
finally SARS-CoV-2 (causing COVID-19 disease). Throughout
that period, mankind has not shown a high ability to combat these
pandemics. This serious situation required new strategies to deal
with such viral diseases and effective antiviral agents are urgently
needed to combat them. Vaccination, cellular therapy, and
immunotherapy may be brilliant therapeutic strategies. However,
medicinal plants could play an intrinsic role to tackle the Covid-
19 pandemic. Scientific researches on plant products as possible
anti-COVID-19 are scant and neglected. In the current study,
some compounds of medicinal plants that have demonstrated
potential anti-viral properties are recommended for further
investigations against COVID-19. Finally, the risk of similar
coronavirus outbreaks in the future remains high unless we use all
possible remedial measures, and medicinal plants remain the best
sources and it should not be neglected in our struggle with
COVID-19 disease.
Acknowledgment
None
Conflicts of Interest
The authors declare no conflict of interests.
Funding
This research is not supported by any organization or institution.
Ethical Approval
Non-applicable
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