Mukunuwenna: The Cooling Herb for Eye Health

Introduction to Mukunuwenna

Mukunuwenna (Alternanthera sessilis) is a rapidly growing, prostrate, and creeping aquatic or semi-aquatic plant found abundantly in the wet zones of Sri Lanka. While considered a weed in some parts of the world, it is highly prized in Sri Lankan culinary and traditional medicinal practices. In Ayurvedic philosophy, it is celebrated for its deep cooling effects on the body and its specific affinity for treating ocular (eye) conditions.

Nutritional and Phytochemical Profile

Mukunuwenna is an exceptional source of micronutrients. It is incredibly rich in provitamin A (beta-carotene), Vitamin C, dietary fiber, and essential minerals including iron, calcium, and potassium. Phytochemically, the plant contains active sterols, triterpenes, and flavonoids such as vitexin, which contribute to its potent antioxidant activity.

Evidence-Based Health Benefits

1. Vision and Ocular Health

Traditional practitioners strongly recommend Mukunuwenna for patients suffering from blurred vision, dry eyes, and night blindness. This traditional wisdom is supported by the plant's exceptionally high beta-carotene content, which the liver converts into Vitamin A, an essential nutrient for the maintenance of a healthy cornea and the synthesis of rhodopsin (the pigment required for low-light vision).

2. Hematinic Properties (Treating Anemia)

In traditional medicine, the herb is prescribed to pregnant women and individuals suffering from iron-deficiency anemia. The high bioavailability of iron in the leaves, combined with a rich concentration of Vitamin C (which vastly improves iron absorption), makes Mukunuwenna an excellent dietary intervention for improving hemoglobin levels.

3. Hepatoprotective and Antioxidant Activity

Animal studies have demonstrated that extracts of Alternanthera sessilis exhibit significant hepatoprotective properties, shielding the liver from toxin-induced damage. The flavonoids present in the plant scavenge free radicals, reducing oxidative stress and lowering systemic inflammation.

How to Use

Due to its slightly tough texture, Mukunuwenna is rarely eaten raw. The most popular preparation is Mukunuwenna Mallum. The leaves and tender stems are finely shredded and lightly stir-fried or steamed with freshly grated coconut, turmeric, onions, and Maldive fish. Cooking it lightly with a fat source (coconut) is essential, as it significantly increases the bioavailability of its fat-soluble beta-carotene.

Scientific References

• Lin, S. C., Lin, C. C., Lin, Y. H., Supriyatna, S., & Teng, C. W. (1994). Protective and therapeutic effects of Alternanthera sessilis on carbon tetrachloride-induced hepatotoxicity in rats. The American Journal of Chinese Medicine, 22(02), 153-162.
• Walter, A., et al. (2014). Nutritional and Medicinal value of Alternanthera sessilis: A Review. International Journal of Pharmacy and Pharmaceutical Sciences.
• Gunathilake, K. D. P. P., & Ranaweera, K. K. D. S. (2016). Antioxidant properties of 34 green leafy vegetables consumed in Sri Lanka. Food Chemistry, 212, 597-603.