Commelina communis, also known as white commelina or Lina, is the stem pith of the plant Phyllostachys heterocycla. "Bencao Shi Yi" states, "Phyllostachys heterocycla grows on the side of the mountain, with leaves resembling ramie, and a lovely white pith inside, which is used by women to decorate. 'Erya' refers to it as Lina or Lina Tuo." It has a cool nature and a mild taste, and it enters the spleen and stomach meridians. It has the effects of clearing heat and promoting diuresis, promoting ventilation and lactation. It is commonly used to treat symptoms such as red and hot urine, painful urination, edema with reduced urine output, lack of milk secretion, dizziness, and nasal congestion. In the market, dried stem pith of the Hydrangeaceae plant Hydrangea macrophylla is sometimes falsely sold as Commelina communis. When using it, attention should be paid to identification.
Authentic Commelina communis
The dried stem pith is cylindrical, generally 0.3-0.6 meters long, with a diameter of 1.2-3 centimeters. The surface is clean white or pale yellow, with shallow longitudinal grooves. It is light and soft, with elasticity. The cross-section is flat, with a 0.5-1.5 centimeter hollow or white translucent film in the middle. The outer ring is silver-white, and there are layered membranes visible in the longitudinal section. There is no odor and the taste is mild.
False Hydrangea macrophylla
The stem pith is cylindrical, 30-50 centimeters long, with a diameter of 0.3-0.9 centimeters. The surface is light yellowish white or light brownish yellow, without texture. It is light and flexible, and can be curled into small rings. It can be deformed when squeezed. The cross-section is solid, flat, and has a silver-white luster. There is no slippery feeling when soaked in water. There is no odor and no taste when tasted.
"Compendium of Materia Medica" states, "Commelina communis is white in color and cool in nature, with a mild taste and light body. Therefore, it enters the Taiyin lung meridian, dispels heat and promotes urination; it enters the Yangming stomach meridian, promotes ventilation and lactation. Its cool nature makes it descend, and its mild taste makes it ascend." Since false Hydrangea macrophylla does not belong to the same family as Commelina communis, and the woody part of the stem does not have the same effects as Commelina communis, it cannot be used as a substitute for Commelina communis in medicine. Therefore, careful identification is required when using it.
