The flavonoid nasunin isolated from the peel of the eggplant fruit is a potent antioxidant and free radical scavenger and has been demonstrated to guard cell membranes from damage.
EGGPLANT SEASON New Mexico's August heat brings the chiles and the eggplants. A new harvest every day. I pick the eggplants when they're soft and tender, no need to peel or salt, and then grill, roast, or stew. Eggplants stewed in soy sauce with chiles and garlic over noodles - my favorite comfort food from rainy days studying Chinese in Taiwan.
HISTORY The eggplant (Solanum melongena) is a plant species in the nightshade family Solanaceae. Botanically a fruit, large eggplant (brinjal) are indigenous to India and small eggplant (茄子) are indigenous to China. The texture of eggplant brings an earthiness and heft to vegetable-based cuisines and vegetarian diets. Chefs recommend that eggplant not be stored hot or cold. It is highly perishable.
Medieval Europeans were ambivalent toward eggplant, perhaps because of the bitter taste of earlier cultivated varieties. The literature warns about bitterness and pungency and the belief that eggplant creates a melancholic and angry mood. Salting and rinsing counteracted these properties, which are far less pronounced in current eggplant cultivars. Since the development of varieties without the bitter taste, the popularity of eggplants has increased. They are now celebrated worldwide for their health benefits and medicinal properties.
Henry C. Lu notes in the Chinese System of Food Cures: Preventions and Remedies that eggplant nourishes the blood, supplements vegetarian diets, and contains vitamin P (flavonoids). Eggplant possesses anticancer and antioxidant effects and prevents hardening of the blood vessels. Historically, in Traditional Chinese Medicine, eggplant was used to treat abscesses as well as for intestinal bleeding and toothache.
Pakistan Journal of Nutrition (2004). Rabbits fed a normal diet supplemented by eggplant had lower levels of lipids in the blood and increased levels of high-density lipoprotein cholesterol (good cholesterol). There were strong hypolipidemic effects from Solanum melongena and Solanum gilo, as well as an improved HDL/LDL ratio, indicating eggplant's potential for treating ischemic heart disease and arteriosclerosis.
Modern Medical Laboratory Journal (2018). The cytotoxic effects of eggplant peel extract on human gastric cancer cells and normal cells from a cell bank in Iran were investigated. Delphinidin 3-rutinoside-5-galactoside may have antioxidant properties and protective activity against lipid peroxide. A relationship between eggplant’s cytotoxic effects and its antioxidant activity has been demonstrated.
Food Elixir Science (2014). An evaluation of the nutrient and phytochemical constituents of four eggplant cultivars found high concentrations of alkaloids, tannins, and saponins. Tannin compounds have antibacterial, antiviral, and antiparasitic effects, and alkaloids and saponins have antimicrobial properties. Polyphenols may promote the uptake of glucose in tissues and improve insulin sensitivity.
Journal of Carcinogenesis & Mutagenesis (2013). Three steroidal alkaloids and two steroidal glycosides isolated from the peel of Solanum melongena L. exhibited moderate to potent activity against human cancer cell lines – activity was most pronounced against liver cancer cell lines. Subsequent in vivo testing against hepatocellular carcinoma in rats demonstrated reduced tumor marker levels. The compounds also restored levels of AST, ALT, and albumin.
CHEMICAL CONSTITUENTS OF EGGPLANT
Phytonutrients in eggplant include vitamin B1 (thiamine), vitamin B6 (pyridoxine), copper, manganese, potassium, magnesium, vitamin B3 (niacin), and vitamin B9 (folate).
The flavonoid nasunin isolated from the peel of the eggplant fruit is a potent antioxidant and free radical scavenger; it has been demonstrated to guard cell membranes from damage. Flavonoids extracted from the fruits of Solanum melongena showed significant hypolipidemic potential in rats.
The nightshade family is rich is alkaloids. Solanine is the bitter glycoalkaloid found in the vegetation and fruits of most Solanum species. Raw eggplant contains solanine and the fruit should be cooked before eating. Eggplant also has substantial levels of oxalates. If you have a history of oxalate-containing kidney stones, then you should eat eggplant in moderation.
Infants and children Avoid feeding raw eggplant to babies and toddlers. Eggplant contains compounds that may irritate the digestive system. Nitrates in eggplant convert to nitrites when cooked and may present a hazard to infants younger than four months. It is important to know the symptoms of nitrite poisoning.
People with chronic inflammatory conditions might consider limiting consumption of eggplant until the cause of the inflammation is resolved.
Please note: The medicinal properties of eggplant are described above for educational and historical purposes only. This information is not intended to replace the advice of a healthcare provider.
Kerilyn Sappington is the founder of Integrative Translations, which specializes in the Chinese to English translation of topics in conventional and complementary medicine.