Bioactive Compounds and Biological Activities of Lotus (Nelumbo nucifera Gaertn.)

Nelumbo nucifera Gaertn. Gaertn.Lotus (Nelumbonaceae A. Rich.) is a beautiful aquatic flowering plant with a subterranean rhizome. With a vast array of culinary applications and a storehouse of bioactive compounds in its plant parts, N. nucifera functions as both an underground food crop and a valuable medicinal plant. With a more than 7,000-year history of cultivation, this plant is one of the few aquatic plants used as a vegetable. N. nucifera possesses copious amounts of alkaloids and flavonoids as phytochemicals, along with various other derivatives. The rhizome is consumed as a vegetable since it has more carbohydrates, proteins, and vitamins, and it also possesses phytocompounds that exhibit immunomodulatory, antiviral, and antioxidant properties. Many countries in Asia use N. nucifera starch as a major culinary ingredient. To date, many phytochemicals isolated from this plant are used in many medicinal systems, including traditional, Ayurvedic, herbal, and oriental medicine. The extracts of various organs of this plant are used to treat numerous types of cancers, cardiac diseases, liver ailments, diabetes, and nervous disorders. The flower extracts are effective against fever, adipsia, cholera, and diarrhea. Eaten raw or puffed, lotus seeds are high in protein and contain minerals like calcium, phosphorus, iron, and potassium. The seeds are used as antibiotics to cure skin diseases like leprosy. Chinese medicine uses lotus seeds to treat renal and cardiac problems. Accordingly, N. nucifera is employed in food, medicine, culture, and religion. Furthermore, N. nucifera is an excellent environmental adapter and has the capacity to modify its resistance to environmental stress in order to adapt to a variety of abiotic stresses including flooding, extremely high temperatures, salt, low light, and heavy metals. It can therefore be grown in a variety of environments. Although this aquatic crop is restricted to an extensive geographical region and has a huge variety of cultivars, many parts of the world are still uninformed about this crop. Therefore, it is crucial to comprehend the medicinal and nutritional benefits of this tuberous crop in order to investigate it as a potential replacement for present-day food crops as well as a source of medicine. In order to effectively utilize this aquatic underground crop, this chapter aims to embody the nutritional advantages, traditional uses, phytochemistry, and bioactivity of the phytocompounds from the various parts of N. nucifera. It also emphasizes lotus breeding to date, applications as food, cultural aspects, and future production of potential N. nucifera underground crops of the highest quality.