Medicinal Plants in the prevention and Treatment of COVID-19 Pandemic: From folklore to pharmacy lab
The whole world is entangled in the coronavirus disease (COVID‐19) pandemic caused by severe acute respiratory syndrome coronavirus (SARS‐CoV‐2).
By Ghulam Abbas Narejo *, H. U Khan, Muhammad Ismail Bhatti, Zil-E-Haleefa, Amir Hussain
COVID-19 was declared a pandemic by the World Health Organization (WHO) on March 11, 2020, because of its rapid transmission and infection rates worldwide. This disease is characterized by progressive and severe pneumonia, and the most common symptoms are fever, dry cough, fatigue, and headache. However, recent evidence indicates that multiple neurological complications could present in COVID-19 patients. People are dying in thousands each day without an actual medication.
Currently, the search to identify treatments and vaccines for novel coronavirus disease (COVID-19) is ongoing. Desperation within the community, especially among the middle-and low-income groups acutely affected by the economic impact of forced lockdowns, has driven increased interest in exploring alternative choices of medicinal plant-based therapeutics.
Medicinal plants have been used in healthcare since time immemorial. Studies have been carried out globally to verify their efficacy and some of the findings have led to the production of plant-based medicines.
A lot of misinterpretations of the use of medicinal plants to treat or prevent COVID-19 have been spreading throughout the world.
This is evident with the rise in unsubstantiated efficacy claims of these interventions circulating on social media. Based on inquiries received, scientists and researchers throughout the world were given the chance to produce evidence summaries evaluating the potential of complementary interventions in COVID-19 management.
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 (Sweet Wormwood), Agastache rugosa (Korean mint), Astragalus membranaceus (Mongolian milkvetch), Cassia alata (Candle Bush), Ecklonia cava (brown alga), Gymnema sylvestre (Australian cowplant), Houttuynia cordata (Chameleon Plant), Lindera aggregate (lindera), Lycoris radiata (Red Spider Lily), Mollugo cerviana (Thread stem carpetweed), Polygonum multiflorum (tuber fleece flower), Tinospora cordifolia (Guduchi), etc. have shown promising inhibitory effect against coronavirus. Several molecules, including acacetin, allicin, curcumin, daidzein, diosmin, emodin, herbacetin, lycorine, etc. isolated from plants could also be potential drug candidates against COVID‐19. This research creates a determined hope for future phyto-vaccines.
In China, Nepal, and other Asian countries researchers have found the usefulness of more than 60 plant species namely, ginger, garlic, neem tree, lemon, black cumin (Kalonji), etc, against antiviral, anti-inflammatory, and immunomodulatory effects in COVID-19 management.
Similarly, China, India, Bolivia, Morocco, Nepal, Peru and Brazil, and Columbia are using traditional medicine against COVID-19. There are approximately 50,000 plant species with medicinal uses, and the WHO has estimated that 80% of the population of developing countries uses traditional medicine as their main source of medicines. In Europe, WHO has indicated that 71% and 40% of the population of Chile and Colombia, respectively, use traditional medicines to treat COVID-19.
A recent study has reported an association between the use of 17 medicinal plants and the treatment or prevention of the respiratory symptoms related to COVID-19, and the most used plants were eucalyptus, ginger, spiked pepper, and garlic.
Recent literature also suggests that some of the antiviral medicinal plant species such as orange (Citrus sinensis), Allium sativum (Garlic), Allium cepa (Onion), Mentha piperita (Peppermint), and Nigella sativa (Kalonji) are the most desirable herbal drink or fruit that can introduce effective adjuvant components in COVID-19 management.
Traditional herbal medicine seems to have revealed encouraging results in reducing the rate of mild, severe, overall mortality, and shortening total disease duration. When combined with modern biomedicine, herbal medicines could exert antiviral; relieve chronic obstructive pulmonary disease and hypoxemia, immune-regulatory, and anti-inflammatory activities. Similarly, traditional medicines are used for the management of COVID-19 parallel with modern medicine and vaccinations.
In Pakistan, some medicinal plants as discussed above are also found and can be well used for treatment against COVID-19, respectively. But there is still a need for research and development to extract some valuable medicines from them for future phyto-vaccines.
Ghulam Abbas Narejo *, H. U Khan, Muhammad Ismail Bhatti, Zil-E-Haleefa, Amir Hussain
Botanical Science Division, Pakistan Museum of Natural History, Islamabad