The insight and survey on medicinal properties and nutritive components of Shallot

Shallot is a horticultural commodity belonging to spice vegetables. Shallot (Allium ascalonicum L.) is a perennial crop which is grown as an annual for its cluster of small cloves and bulbs. Persian shallot also is native and endemic of Iran and grows as a wild plant across Zagross mountains at high elevations. Shallot is an important source of carbohydrate, vitamin A, B, and C. Phenolic compound in Shallot consist of gallic acid, apigenin, eriodictyol, quercetin, isoquercetin, rutin, kaempferol, catechin and tannic acid. The most important health benefits of shallots are reduction of cancer risk, improve heart health, aid detoxification, help control diabetes, improve brain health, help to fight obesity and treat allergies, boost bone health, maintain vision health, boost immunity, improve skin health, increase abdominal health and keep hair healthy. The dominants medicinal properties of Persian shallot is it antibiotic, hypolipidemic, anticancer, antioxidant, hypoglycemic, kidney protective and hepatoprotective properties. This review article allowed verifying shallots as sources of compound s with valuable nutritional and bioactive properties with great ability for incorporation into foods with functional properties. Also, treatment with natural herbal medicine like shallot as non-synthetic drug is recommended.


INTRODUCTION
Both natural products and traditional medicines have great importance (Shahrajabian et al., 2019a, b, c;Sun et al., 2019). Traditional medicine refers to health practices, knowledge, approaches and beliefs incorporating plants and herbs based on bot h ancient and modern pharmaceutical science (Ogbaji et al., 2018;Shahrajabian et al., 2019d,e). Traditional Asian medicine plays an important role in sustainable agriculture and food systems; it also offers a holistic and signific ant approach to prevent diseases while making suitable usage of organic and herbal products (Soleymani and Shahrajabian, 2012;Ogbaji et al., 2013;Ge et al., 2018;Shahrajabian et al., 2018;Soleymani and Shahrajabian, 2018).

SHALLOT OCCURRENCE AND CULTIVATION
Shallot is one of the most important vegetable crops in *Corresponding author. E-mail: chengqi@caas.cn.
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License various local cuisines in different part of the world (Sulistio et al., 2015;Yao et al., 2017;Tabor, 2018). Shallot (Allium ascalonicum L.) is a perennial crop which is grown as an annual for its cluster of small bulbs or cloves. Shallots are valuable spices for both flavoring dishes and as medicinal plants (Swamy and Veere Gowda, 2006). Greek history and literature mention shallots. It most likely originated in S outheast Asia and from there, spread into India and the Mediterranean region. Shallot is a hardy member of the onion family that is famous for its delicate, meaty, onion -like flavor. Persian shallot, a bulb producing plant from Alliaceae, is a wildly growing plant collected for its bulbs, and it is called Mooseer in Farsi, are oval, white skinned and completely different from common shallot (Allium ascalonicum) (Ebrahimi et al., 2019). Persian shallot is native and endemic of Iran and grows as a wild plant across Zagross mountains at high elevations of different provinces from Nort hwestern to Sout hern of Iran with the climate of very cold to moderate cold (Moradi et al., 2013). Shallot is a major component of many Asian diets and is widely believed to be beneficial to health (Jalal et al., 2011). Tesfa et al. (2015) found that shallot can be a substitute where bulb onion does not do well, however, the production of shallot can be limited due to poor soil fertility, lack of improved production techniques, unimproved varieties and high post-harvest losses. Shallots are a unique vegetable that is used by domestic consumers as every day seasoning, raw materials of food industry, and medicine (S ukasih, 2015). The most common dis eases of shallots are downy mildew, bacterial soft rot and neck rot, and the most important insects are onion maggot and onion thrips.

CHEMICAL CONSTITUENTS AND HEALTH BENEFITS
Shallot is a source of carbohy drat e, vitamin A, B, and C. Fasihzadeh et al. (2016) noted that 1-But ene, 1-(methylthio)-(Z) (18.21%), methyl methylthiomethyl disulfide (8.41%), dimethyl tetrasulfide (6.47%), and piperitenone oxide (4.55%) are the most abundant components of Persian s hallot and comprised 37% of t he essential oil. Ebrahimi et al. (2008) showed that Iranian shallot landraces are important in mineral elements and essential fatty acids content and are rec ommended for human nutrition. Sittisart et al. (2017) showed that shallots extracts contained some polyphenols such as apigenin, gallic acid, catechin, querc etin, kaempferol and tannic acids which are famous compounds possessing antifungal activity. Golubkina et al. (2019) indicated that shallot is an excellent candidate for the health-centered strategy of producing functional foods wit h high levels of Se and antioxidants; and the usage of arbuscular mycorrhizal fungi and selenium application represent environmentally friendly strategies to enhance the overall yield and quality performances of shallot bulbs. Fattorusso et al. (2002) reported two new furostanol saponins, named ascalonicoside A 1/A2 (1a/1b) and ascalonicoside B(4), respectively, along with compounds 2a and 2b. Phaiphan et al. (2019) discovered that heating and shallot supplementation can massively improve t he quality of apple juice. Yin et al. (2006) suggested the use of shallot and scallion oils in food systems which may enhance lipid and microbial stability. Raeisi et al. (2016) concluded that the application of 3% ajwain seed extract gave the best antioxidant and antimicrobial activities, as well as sensory, up to 15 days of storage, followed by 3% shallot fruit extract. Leelarungray ub et al. (2006) stated that organic solvent and aqueous extracts of garlic and shallot bulbs had significant antioxidant potential, as measured by decreases in free radicals and an ability to inhibit lipid oxidation. Wongmekiat et al. (2008) indicat ed the protective potential of shallot extract against CsA nephrotoxicity and suggest a significant contribution of its antioxidant property to this beneficial effect. Abdelrahman et al. (2017) provided evidence for the anticanc er from shallot plants and a strong foundation for more investigations to build theoretical bases for cell apoptosis and development of novel anticancer drugs. Seyfi et al. (2010) proved that shallot is a useful herb with therapeutic or preventive activity against angiogenesis related disorders. Chen et al. (2011) have shown the potential of shallots for use in treating adenoviral infection activities. Krejc ova et al. (2014) found the usage of Persian shallot for the treatment of inflammatory disorders. They introduced 2-[(Methylthio)methyldithio] pyridine N-oxide with high anti-inflammatory effects. Hajian et al. (2018) showed that shallot extract can dose dependently reduce the factors related to lead induc ed renal damages. Falahati et al. (2011) indicated that crude juice of shallot has anti-candidal activity and might be promising in the treatment of candidiasis. Kongkaew and Phichai (2010) found that dried shallot powder, was effective at inhibiting the growth of Trichoderma spp. isolated from Yanagi mushroom. Noengpa (2004) mentioned that water extract of shallot showed inhibitory effects on C. gloeosporioides and Fusarium sp. spore growth. Amin et al. (2009) noticed that based on the antimicrobial compounds, shallot can be effective medicine for treatment of dermatomycosis and other infectious diseases. Jalal et al. (2011) found that Iranian shallot extracts appear to improve learning and mem ory impairments in fructose-fed rats. Mohammadi-Motlagh et al. (2011) indicated that shallot can be a candidate for prevention and treatment of many diseases related to inflammation and malignancy. Leelarungrayub et al. (2004) indicated that hexane-extract shallot had very high activity on protecting the human erythrocyte from radicals and is possible to be modified for medical plants or commercial product in the future. Sadat Hosseini et al. (2017) found that the Persian shallot extract could be considered as a potential candidate for production of drug for the prevention or treatment of human hepatoma.  1  Allicin  2  Saponins  3  Sapogenins  4 Ajoene 5

S/N Component
Sulphuric compounds (thiosulfinates) 6 Flavonoids: Quercetin and Kaempferol 7 Mineral Elements 8 Essential fatty acids 9 Folic acid 10 Protein 11 Fiber 13 Vitamin C Iranian shallot extracts appear to improve learning and memory impairments in fructose-fed rats (Razieh et al., 2011). Amanzadeh et al. (2006) proved the inhibitory effect of Persian shallot hydroalcoholic extract on Leishmania infantum. Nasiri Kashani et al. (2009) indicated that shallot crude juice has antifungal activity and looks promising to be an alternative for chemical antifungal agents that have sometimes serious effects. Rattanachaikunsopon and Phumkhachorn (2009) Farajii et al. (2018) stated that the shallot extract was preferred in both terms of reducing microbial growth and suitable sensory properties. Zarei Mahmoudabadi and Gharib Nasery (2009) concluded that the fresh crude juice of shallot bulbs has mark edly antifungal effect, and also shallot extract has more antisaprophytes effect at 0.25% followed by C. albicans and dermatophytes. Kazemian et al. (2017) noted that hydroalcoholic shallot extract increas es the number of germ cells in mic e tested and helps amplify the sexual ability of male mice. Shallot as traditional medicine are for febrifuge, diabetes, blood sugar and blood cholesterol, and also prevents thickening and hardening of the blood vessels and ulcers (Sukasih, 2015). Sukasih (2015) also report ed that shallot powder is widely used as an industrial raw material such as in snacks production, seasoning in cooking, and medicine. Persian shallot has been report ed to have a range of health benefits which include anticarcinogenic, hypoglycemic, hypolipidemic, antioxidant, antibiotic properties, and kidney and liver protective effects (Moradi et al., 2013). Contents of polyphenols in extract of chili, shallot and garlic are shown in Table 1. Some components found in Persian shallot are presented in Table 2. Medicinal properties of in Table 3. Volatile organic compounds in shallot with absorption on SPME fiber at 20°C are presented in Table 4.  (Moradi et al., 2013).

S/N Properties 1
Antibiotic properties 2 Hypolipidemic properties 3 Anticancer properties 4 Antioxidant properties 5 Hypoglycemic properties 6 Kidney protective properties 7 Hepatoprotective properties Volatile organic compounds in shallot with absorption on SPME fiber at 50°C are presented in Table 5. The most important health benefits of shallots are shown in Table  6.

Conclusion
Shallot is a key part of diet of many populations and there is long-held belief in their health enhancing properties.

S/N Benefit 1
Reduction of cancer risk 2 Improve heart health 3 Aid detoxification 4 Help control diabetes 5 Improve brain health 6 Help fight obesity 7 Help treat allergies 8 Boost bone health 9 Might maintain vision health 10 Boost immunity 11 Improve skin health 13 Enhance abdominal health 14 Keep Hair healthy Historically, the shallot has been used for bot h its nutritional and aromatic properties in Iranian, Indian, Chinese, Asian, French and Mediterranean cooking. The shallot is considered an important plant in Asian medicinal practices and is commonly prescribed as an effective remedy for various ailments in Ayurvedic medicine. Shallots, like onions, are a member of t he allium family, but their flavor is richer, sweet er, yet more potent. The most important benefits of shallots are high source of antioxidants, improve heart health, cancer prevention, diabetes, anti-inflammatory, antimicrobial, might help fight obesity, and help to prevent or treat allergies. The demand for shallot products is increasing every year with increase population growth and food industries. More clinical studies may be required to uncover the numerous substances and their effects in shallot that contribute to public health.