Turmeric is being used as a spice and a traditional medicine for the treatment of swelling, distress, chronic inflammation and gastrointestinal problems. Significant preclinical studies have shown that a variety of chronic conditions could be addressed by Turmeric and its biologically active curcuminoid polyphenols. Global turmeric output is projected to reach 1.5 million metric tonnes by 2027. It has been reported over the period 2020-2027 (https://www.reportlinker.com/p05960349/Global-Turmeric-Industry.html) that, the “International Turmeric Industry” will grow at a compound annual growth rate (CAGR) of around 3.9 percent. An average 4 percent CAGR is expected to be recorded by a few of the divisions analysed in the report and reaches 1 million metric tonnes even by end of the analysis duration. The development in the pharmaceuticals & other segments are projected to be updated to a 3.6 percent CAGR over the next 7 years. It is projected that perhaps the U.S. market will grow at 302.9 thousand metric tonnes, while China is expected to grow at 7% CAGR (https://www.reportlinker.com/p05960349/Global-Turmeric-Industry.html). By 2027, China has projected the size of the market of 313.8 thousand metric tonnes, which represents a 7 percent increase in CAGR over the 2020 to 2027 analysis period. The 2012-2027 turmeric global market projections (Figure 1) show the value of the international turmeric market in 2012 and 2016 and provide a forecast for 2027. The global turmeric market was valued at about US$3.16 billion in 2016 (https://www.statista.com/statistics/740259/global-turmeric-market-volume/). In Japan and Canada, over the 2020-2027 period, growth is estimated at 1.2 percent and 3 percent, respectively, whereas Germany is projected to grow at 2 percent CAGR. India has the world’s largest number of farmers, consumers and suppliers of turmeric. Because of the condition of elevated curcumin quality, Indian Turmeric is regarded as the best graded Turmeric (https://www.reportlinker.com/p05960349/Global-Turmeric-Industry. html). The main Turmeric exporting areas are India, Thailand, Taiwan, and Southeast Asia, Central, and Latin America (https://economictimes.indiatimes.com/topic/Turmeric-market). The largest importers of Turmeric are in Japan, Sri Lanka, Iran, the UAE, the United States, the United Kingdom and Ethiopia (https://economictimes.indiatimes.com/topic/Turmeric-market). Telangana, Andhra Pradesh, Tamil Nadu, Karnataka, Odisha, West Bengal and Maharashtratra are the major turmeric producing states in India. The 2018-2019 statistics show that even in India, 47,888 hectares were covered by government of Telengana growing turmeric compared to 44,956 hectares last year. The beginning stocks were reported to be around 1.32 lakh tonnes as per Turmeric supply figures presented in Figure 2 for 2018-19, while end stocks were only about 0.71 lakh tonnes due to increase in the number of internal demand and export for the year 2018 under a low production condition (https://economictimes.indiatimes.com/topic/Turmeric-market). The potential incentives for the production, exports and imports of Turmeric for pharmaceutical usage could be attributed to the presence of active compounds such as curcumin, demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) which are collectively known as curcuminoids [1] [2]. These curcuminoids were isolated from rhizomes of Turmeric plant and generally yellow in colour [3]. Curcumin, which has a small relative molecular mass, is one of the most interesting components of the curcuminoid, and is a polyphenolic compound. At the acidic pH of the stomach, curcumin is stable. Natural compounds, including tumerone, atlantone, zingiberone, sugars, proteins and resins are the other constituents present [4] [5]. It is a tautomeric compound found in organic solvents and water within the enolic and keto form. Turmeric is usually like fingers with bulbs and splits, 2 to 8 cm long and 1 to 2 cm wide. After harvesting, rhizomes are dried and further refined in order to acquire the Turmeric in powder form.

For its various benefits, curcumin has been used as a traditional medicine: antioxidant, anti-inflammatory, antimutagenic, antimicrobial and a number of other pharmaceutical properties [6]. Several substances are being used to increase curcumin’s bioavailability, like piperine, which increases its biocompatibility by suppressing its metabolic pathway [6] [7]. Within the root extracts of turmeric, curcumin is an important component. This has been used in Asian countries as a flavouring agent and coloration agent for food and medicine [8]. There are several formulations of curcumin currently available, like pills, tablets and ointments [9]. Curcuminoids were approved as “Generally Accepted as Safe” (GRAS) [10] by the Food and Drug Administration (FDA) of the United States. Turmeric is often used in herbal based treatment for atrophic arthritis, chronic anterior uveitis, conjunctivitis, carcinoma, smallpox, chickenpox, wound healing, tract infections, and liver diseases, strengthening the body’s general capacity, dissipating worms, controlling menstruation, breaking down gallstones, washing wounds, and even for various gastrointestinal issues, among many other conditions. Turmeric’s chemical makeup consists of 3 percent of curcumin, 1.4 percent of demethoxycurcumin and 1.2 percent of bisdemethoxycurcumin [11] [12] [13]. Turmeric has a long history of using it as a spice in Asian cuisines, and in many other areas of the globe. Turmeric is used in countries such as China, India, Iran and Indonesia to cure human diseases and to be used as a tonic for an extended period. Curcumin has three major complexes of curcumin, i.e. curcumin I, curcumin II, and curcumin III [14] [15] [16]. The dry root portion of Turmeric has been observed to contain up to 8 curcumin [17]. The goal of this review is to have a brief overview of the health benefits of curcumin and its capacity for boosting immunity against the ongoing COVID-19 pandemic.

A rich source of carbohydrates and fibre is Turmeric which includes some protein and fat, but there is still a complete absence of cholesterol. In addition, this has an adequate amount of pyridoxine, vitamin C, potassium, calcium, magnesium, and phosphorus, which is reported as a natural food product which is nutritionally efficient. The brief nutritional composition of Turmeric is shown in Table 1 [18]. Turmeric has a broad variety of molecular components, each with a range of biological activities. Overall, Turmeric is identified for approximately 326 biological activities [19]. Curcuminoid polyphenols are the most researched elements consisted of curcumin, bisdemethoxycurcumin, and demethoxycurcumin (Figure 3). For the extraction of curcumin, organic solvents are used as it is insoluble in water. For the isolation of curcumin from grounded Turmeric, a methodology was designed [19] and thin layer chromatography analysis was performed to verify the presence of different components which have also shown that turmeric contains a large number of ingredients and Figure 4 indexes their percentage [20].

Curcumin is likewise called diferuloylmethane and the IUPAC name of Curcumin is (1E-6E)-1,7-bis(4-hydroxy-3-methoxy phenyl)-1,6-heptadiene-3,5-dione with compound recipe C₂₁H₂₀O₆ and sub-atomic mass 368.385 g/mole [21]. In the curcumin structure, there are two oxy-subbed aryl moieties containing ortho-methoxy phenolic OH gatherings, which is connected by a seven carbon chain comprising of a β-unsaturated β-diketone moiety in which the methoxy bunch is missing from both aryl rings [22]. The reaction of hydrogen-atom donation which contributes to the curcumin oxidation process, the process of nucleophilic addition reactions, the process of hydrolysis, the degradation process and the essential enzymatic reactions are the prominent chemical reactions associated with the biological functional activity of curcumin [23]. Curcumin is hydrophobic in nature with a log P value of 3.43, but is generally not soluble in aqueous medium [24]. In polar solvents like DMSO, methanol, acetone and ethanol, the curcumin is soluble [25]. It can function as a hydrophobic reducing agent and scavenge various reactive oxygen species (ROS) and is better at suppressing the oxidative stress [26] [27]. Pharmacokinetic tests have shown that curcumin is digested to deliver sulfate and glucuronide metabolites upon oral ingestion [28].

Since December 2019, disease outbreak SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) has rapidly spread all throughout entire planet. Hardly any specific drug or vaccine has been approved for its remedy or preventative measures. So far, even though anti-retroviral capsules as well as hydroxylchloroquine etc. have been used for the cure [84]. Various derivatives of curcumin have proof of anti-viral properties. The stimulation assay of neuraminidase demonstrates that five active derivatives of the curcumin additive reduced the activation of H1N1 induced neuraminidase in H1N1 infected lung epithelial cells [85]. This same activation of nucleoproteins becomes even down-regulated by Tetramethyl l curcumin and curcumin. Substantial antiviral activity of Turmeric against H5N1 virus is also determined in Madin-Darby dog kidney (MDCK) cells in vitro by interfering with the activity of infectious hemagglutination (HA) [86], that may be advantageous for recent disease outbreak circumstances. With both the up-regulation of TNF-alpha and IFN-β mRNA expressions within the investigated MDCK cells, that are comprehensive anti-viral agents, the impacts of the anti-H5N1 viral infection with both the assistance of turmeric extracts have been demonstrated [87] [88]. Due to its inhibition activity on HIV protease and integrase, Curcumin is also beneficial in other viral problems like AIDS. Other pathogens also have an inhibition activity due to curcumin, such as hepatitis B, hepatitis C, zika, chikungunya, dengue, etc. The leading cause of COVID-19 death rates is respiratory illness syndrome with fulminant hypercyto-kinemia and multi-organ failure [89] [90]. Curcumin was reported to reduce lung tissue injuries sustained by influenza virus by obstructing the signalling of NF-umB and preventing the release of inflammatory cytokines.

The safety of Turmeric has also been researched in vitro, animal models, as well as drug testing. As per a detailed review on this topic, the organism is not toxic. Cultured cells studies have shown that “curcumin can decrease the growth of probiotic and prove anti-proliferative impacts in healthy cells”. There’s really, even so, hardly any evidence of genotoxicity and mutagenicity. In human beings, this same oral use of curcumin is secure. In a small percentage of cases, gagging, tongue redness, atrial fibrillation, and gastrointestinal problems (e.g., flatulence, diarrhoea, nausea, and constipation) have been observed. There is indeed a biocompatibility issue with intravenous curcumin, so this should be consumed at a dose lesser than oral administration [91]. This should be mentioned that certain sorts of pharmacokinetic modification of cardiovascular medications, antibiotics, antidepressants, chemotherapy drugs, immunosuppressants and corticosteroids may well be triggered by curcumin. Consequently, its simultaneous accessibility with other collectivist medications must be routinely laid out [92]. A slight reduction throughout weight gain in F₂ generation chicks has been triggered by oral curcumin of around 1000 mg/kg body mass, as published in one report [93]. This same security of such modern mixtures must be regarded with respect to the interpretation of drug transfer technologies for improving Turmeric bioactivity. For instance, if carriers or surfactants are being used as a biocompatibility action plan the product could be toxic [94]. Even though most of such innovative technologies occur to also be safe, there are no negative effects in patients with osteosarcoma and also in healthy populations, there are no detrimental effects on solid lipid curcumin formulation [95]. As yet another different framework expressing curcuminoids nasally to the brain, the poly (N-isopropylacrylamide) distribution network demonstrates hardly any noxiousness [96]. Dipeptide curcumin nanomaterials are too safe. A dipeptide is formulated from alpha, beta-dehydro phenylalanine and methionine amino acids which are comfortable and safe to dissolve in nature [96]. In additament, curcumin-loaded blood serum albumin nanoparticles showed hardly any toxic effects during arterial use throughout HCT116 tumour xenograft models [97]. A new intravenous curcumin study showed that rabbits throughout the curcumin nanosuspension group would have a reduced chance of local irritation and phlebitis and erythrocyte hemolysis than those from the curcumin solution group [98].

Globally, curcumin is recognised because of its antioxidant, anti-inflammatory characteristics and other potential benefits which are helpful for public health. It improves bioavailability in conjunction with curcumin and piperin. Curcumin also might deal with oxidative, inflammatory, metabolic, arthritis, anxiousness and hyperlipidemic diseases. Exercise-induced inflammation and sore muscles are monitored as well as enhanced by inactive individuals throughout rehabilitation and performance level. In addition, for people who have not yet been successfully treated with any disease, it’s indeed beneficial. The root is the core aspect of Turmeric and includes more than enough bioactive compounds, vitamins and minerals, trying to make this the safest therapeutic herb. It is also used in pregnancy as well as during renal or hepatic failure in lactating women. It includes curcumin, the most main bioactive element, accompanied by certain substances like atlantone curcuminoid, dimethoxycurcumin, diarylheptanoid, tumerone, and diferuloylmethane flavonoid curcumin. These have antibacterial, anti-inflammatory, and antioxidant activity which safeguard against different cellular injuries. In addition, psychological diseases such as Parkinson’s and Alzheimer’s diseases also are successfully treated by Turmeric. It is also efficient against metabolic syndrome and different forms of cancer. In summary, to regulate a wide range of human illnesses, this can be added to dietary foods. A major emergence in China in December 2019 of the highly contagious novel coronavirus (COVID-19), spread across the world to a new pandemic [99]. It is caused by the novel SARS-CoV-2 Corona virus (severe coronavirus 2 acute respiratory syndrome) from the Coronaviridae family. No special antiviral treatment for COVID-19 patients is available to date. The clinicians, including antivirals, antibiotics and anti-inflammatory drugs [99], have considered combination therapy in developing countries. Including hydroxychloroquine, the use has been extensive. In addition, the role of curcumin in the influence of the RAAS (rennin-angiotensin-aldosterone system) components through which anti-oxidant, anti-inflammatory and antimicrobial effects are known has also been thoroughly researched. The role of curcumin in ACE and AT1R downregulation of brain tissue and vascular smooth muscle cells was impacted by animal models, which usually results in the mediated effects of hypertension and oxidative stress on animals, respectively, of the inhibition of angiotensin II-AT1R [100]. For greater understanding and moral judgement over its usage in medical care, even more investigation is essential for implementation throughout the future.

The authors declare no conflicts of interest regarding the publication of this paper.