Immunity Boosting Functional Foods to Combat COVID-19

Apurba Giri

• Publisher: CRC Press
• Year: 2021
• Print ISBN: 9781032151236
• eBook ISBN: 9781000486032
• Edition: 1
• Topic: Medicine
• Subtopic: Nutrition, Dietics & Bariatrics

In this book, several functional foods or food ingredients, their mechanism of immune enhancing properties and use in food products have been discussed through seventeen chapters written by eminent authors. There are several medicinal plants which have significant role for immunity boosting such as Ashwagandha, Tulsi, Shatavari, Giloy, Aloe vera, Amla, Neem, licorice, garlic, ginger, turmeric, rosemary, black cumin, cinnamon, sage, thyme,fenugreek, peppermint, black pepper, clove etc. These have been discussed in detail. Note: T&F does not sell or distribute the hardback in India, Pakistan, Nepal, Bhutan, Bangladesh and Sri Lanka.

CHAPTER - 1

POTENTIAL APPLICATIONS OF IMMUNE BOOSTING MEDICINAL PLANTS IN FUNCTIONAL FOODS TO COMBAT COVID-19

Narayana NMNK

Senior Lecturer, Faculty of Agriculture, University of Ruhuna,
Mapalana, Kmburupitiya-81100, Sri Lanka

E-mail: [email protected]

ABSTRACT

The novel corona virus disease COVID-19 which is caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) became a pandemic causing a huge loss to the lives of the people and to the global economic situation while imposing a significant pressure on the health structures of the nations worldwide. Immunocompromized people are more vulnerable to the infection and are at high risk of death. In the absence of an effective antiviral drug or a vaccine, alternative prophylactic and therapeutic solutions are essentially needed to be used to save the lives of the people from this disaster. The article highlighted the possibilities of utilizing medicinal plants rich in phytochemicals which are having proven immunomodulatory and antiviral activity in developing novel functional foods with acceptable consumer appeal to be used in reducing the risk of SARS CoV-2 infection by strengthening the immune system of the individual and complement the therapeutic measures taken against the disease. Innovative functional foods made by fortification of medicinal plants have a great promise to improve the general health and immensely help the general public against the viral infections such as COVID-19. Nevertheless, more evidences are required through controlled clinical trials to support the safety and efficacy of the functional foods fortified with medicinal plants.

Keywords: Antiviral, Coronavirus, Functional foods, Immune boosting, Medicinal plants, Phytochemicals

INTRODUCTION

Highly contagious novel corona virus disease, COVID-19 which was reported to be originated in the Wuhan city, Hubei Province of China during late 2019, has spread in an unprecedented manner all over the world within a short period of time causing a huge loss, not only to the lives of the people but also to the world economy creating a global crisis. It imposes a significant pressure on the health systems of the countries worldwide. COVID-19 is caused by a RNA virus and was named as Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) (Gorbalenya et al., 2020). As of 15^th September 2020, a total of 2,95,28,057 confirmed COVID-19 cases were reported while 9,34,230 were succumbed to death affecting 213 countries around the world (www­.wo­rld­ome­ter­.in­fo, 2020). However, actual number of infected people might be higher than the reported since, many in the population shows no symptoms. Radiating spread of this disease throughout the world is due mainly to the increased global travel of the people.

In the absence of a known cure or a treatment, the best way is to find alternative solutions to control this pandemic while gradually getting into the normal life until an effective anti-viral therapy and/or preventive vaccine has successfully been developed. Nevertheless, it is essential to keep in mind that the viruses mutate, hampering and overcoming the drug effect, which is also the case of SARS-CoV-2, the novel coronavirus. It is reported that, SARS-CoV has very high mutation rate (Ahmad et al., 2020). Especially for the RNA viruses, the antigenic structure is altered frequently and hence, developing a successful vaccine is a difficult task. Even though a vaccine is successfully developed, it could be less or ineffective when there is a change to the antigenic structure in the existing virus (Mousa, 2017).

Therefore, taking measures to control and prevent the risk of infection is important in managing the current problem of COVID-19. Among the several possible alternatives, taking healthy foods rich in functional ingredients to strengthen the immune system is one of the promising practices that could be recommended because a healthy immune system is vital to protect our body from the invading pathogens including viruses. Some plants especially the medicinal plants contain immunomodulatory phytochemicals which can be incorporated to develop functional foods. Some of the phytochemicals have exhibited broad spectrum antiviral activity for the viruses that shows resistance for the drugs. Those are due to the multifunctional components possess by these plants (Tolo et al., 2006). In this context the foods fortified with medicinal plants/their extracts/powders/essential oils which are having promising immunomodulatory and antiviral effects are of significant importance to fight against COVID-19. Chojnacka et al. (2020) reported that use of plant derived compounds and plant preparations in functional food development is relatively fast because the raw materials i.e. herbs and plants are of natural origin and are already approved for human consumption worldwide.

With the above introduction, the objective of this paper is to compile the information on different medicinal plants with promising immunomodulatory and antiviral properties in general and on COVID-19 in particular, that are having potential applications in functional food developments with favourable consumer appeal.

SARS-CoV-2 and COVID-19

SARS-CoV-2 the virus responsible for the COVID-19 disease is a RNA virus of the family coronaviridae (sub family Coronavirinae) and its lineage is similar to the coronaviruses that causes SARS but genetically distinct (Dhama et al., 2020). It has a spike like projections on its enveloped surface giving it a crown like appearance and hence the name coronavirus (Kumar et al., 2020; Singhal, 2020). Zhou et al. (2020) reported that the virus binds via viral structural spike (S) protein with angiotensin-converting enzyme 2 (ACE 2) receptor and invade the host cell primarily through endocytosis. SARS-CoV-2 virus transmitted from person to person by multiple means such as aerosols, droplets and fomites (Wang and Du, 2020) by contacting with the eyes, nose and the mouth. Symptoms of COVID-19 include fever, cough, myalgia or fatigue and less frequently headache, hemoptysis and diarrhea (Huang et al., 2020). In a study carried out in UK, Menni et al. (2020) reported that loss of taste and smell is also a strong predictor of having been infected with COVID-19. However, the clinical features have a wide range from being no signs or asymptomatic to severe respiratory disorders that need intensive care under hospitalization. Tian (2020) reported that SARS-CoV-2 has shown less severe pathogenesis compared to the SARS-CoV and MERS-CoV, but high transmission competence as evidence by the continuous increase in the confirmed cases worldwide. Further, SARS-CoV-2 has unique characteristics. One such character is around 80% of the affected people shows no symptoms (Day, 2020) and they act as silent carriers and spread the disease. Also there is no guarantee that the patients recovered from the disease are protected from the next time infection (WHO, 2020). Those are the reasons for the high transmission competence of this virus. To date no effective vaccine or antiviral drug is available to treat COVID-19.

Healthy Immune System to Fight Against Diseases

Immune system is a complicated defense system and act to protect the host against invading harmful microorganisms such as bacteria, viruses, fungi, parasites etc. and malignant cells (Calder and Kew, 2002; Venkatalakshmi et al., 2016). Therefore, a healthy immune system is an important weapon to fight against pathogens including viruses such as SARS-CoV-2 that causes the COVID-19. However, it is well documented that the immune-competence of a person is affected by many factors such as age (Castelo-Branco and Soveral, 2014; Scepanovic et al., 2018), sex (Oertelt-Prigione, 2012), genetic variability (Scepanovic et al., 2018), stress (Pruett, 2003), alcohol/drug abuse (Friedman et al., 2003), malnutrition (França et al., 2009), environmental pollution (Venkatalakshmi et al., 2016), lifestyle (Venkatalakshmi et al., 2016) etc. With respect to the COVID-19 pandemic, Wu et al. (2020) reported that the older age patients had both Acute Respiratory Distress Syndrome (ARDS) and death than the others and one of the main reasons is less rigorous immune system that they possess. Therefore, enhancing immunity is definitely one of the ways medical practitioners all over the world have been using to treat this deadly disease (Balkrishna, 2020). Getting a healthy diet is one of the ways among many others such as having adequate quality sleep, stress management, doing regular physical activity and relaxation practices etc. which help to keep the immune system strong. Panyod et al. (2020) mentioned that since treating influenza with large amounts of vitamin C, which is known to boost immunity, has been practiced for decades; it might be an effective nutritional treatment for COVID-19 as well. It has already been reported that, high doses of vitamin C have been administered to the COVID-19 patients in China and some other places in the world and has shown promising results (Balkrishna, 2020).

Medicinal Plants as a Mine of Phytochemicals

Plants are considered as biosynthetic laboratory of phytochemicals (Venkatalakshmi et al., 2016) such as alkaloids, flavonoids, glycosides, steroids, polyphenols, polysaccharides, vitamins, tannins, coumarins, gums, terpenes, terpenoides etc. (Okwu, 2004; Mittal et al., 2014; Venkatalakshmi et al., 2016). Phytochemicals are secondary metabolites that do not essentially needed for the survival of the plant but produced as a response to external stimuli such as infection, changes in the nutrition, climate etc. and accumulated only in certain parts of the plant (Verpoorte et al., 1999). They serve as the natural defense system for the host plant (Venkatalakshmi et al., 2016). Medicinal plants which are rich in phytochemicals have been used from prehistoric times as natural medicines for prophylactic and therapeutic purposes as a safer alternative (Lin et al., 2014; Mittal et al., 2014; Ahmad et al., 2020). Medicinal plants contain properties or compounds which can be used for therapeutic purposes or those that synthesize metabolites to produce useful drugs. Immune-modulatory and antimicrobial (including antiviral, antibacterial, antifungal, antiprotozoal, anthelmintic) activity are few of the potentials among many others such as anti-oxidant, anti-diabetic, memory enhancing, cholesterol lowering, anticancer, anti diarrheal, anti inflammatory, anti hypertensive, anti allergic, anti asthmatic, anti arthritic, adaptogenic, anti stress etc. possess by phytochemicals present in these plants (Goel et al., 2010; Pavaraj et al., 2011; Hemalatha et al., 2011; Venkatalakshmi et al., 2016; Vinaya et al., 2017).

Utilization of Medicinal Plants for the Fortification of Functional Foods

Haslberger et al. (2020) in their mini review, referring to WHO expert report on clinical studies on combination treatments for SARS which has immerged earlier, mentioned that functional foods possess a huge possibility for avoiding the mechanisms of viral infection and altering immune responses. The functional food concept was initially introduced by Japanese scientists in 1984, and in Japan, those foods have been marketed as “Foods for Specified Health Use” (FOSHU). Roberfroid (2000) defined functional foods as the foods whic...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Dedication
• Table of Contents
• Preface
• Acknowledgements
• 1. Potential Applications of Immune Boosting Medicinal Plants in Functional Foods to Combat COVID-19
• 2. Tulsi-A Potential Immune Boosting Functional Food Ingredient to Combat COVID-19
• 3. Potential Use of Curcumin to Combat COVID-19
• 4. Use of Ashwagandha to Boost Immunity to Combat COVID-19
• 5. Boosting Immunity by Liquorice (Yashtimadhu) in COVID-19 Pandemic Situation
• 6. Role of Indian Herbs in Boosting Immunity
• 7. Potential Benefits of Berries and Their Bioactive Compounds as Functional Food Component and Immune Boosting Food
• 8. Effectiveness of Flax Seed, an Immune Booster Functional Food during COVID-19 Pandemic Situation
• 9. Dragon Fruit: The New Functional Food and Its Potential Use in Treating Co-Morbid Diseases in the COVID-19 Situation
• 10. Mushroom Exopolysaccharides: Their Antioxidant and Antiviral Properties to Boost Immunity Against COVID-19
• 11. Broccoli - as Immunity Booster Against COVID-19
• 12. Perspective of Green Tea: Its Immunomodulatory Action and Health Benefits
• 13. Application of Probiotics and Fermented Foods in Immunostabilization
• 14. Immune-Boosting and Nutraceutical Applications of Whey Protein: Current Trends and Future Scope
• 15. Biofunctional Properties of Traditional Indian Fermented Milk Foods for Immunity Boosting
• 16. Immune-Boosting Role of Zinc against COVID-19
• 17. Vitamin D Supplementation to Combat COVID-19: A Review