Gracilaria/Gracilariopsis lemaneiformis
Aliases：Jiang Li、Hai Cai、Xian Cai、Fa Cai、Hai Mian Xian、Zhu Tong Cai、Feng Wei Cai、Niu Mao, etc.
Longxucai (Dragon‘s Beard Seaweed), a Chinese medicinal, is the thallus of Gracilaria asiatica Zhang et Xia, Gracilaria chouae Zhang et Xia, Gracilaria lemaneiformis (Bory) Weber‑van Bosse, and other related species of the Gracilariaceae family.
Efficacy & Actions
Clear heat and resolve toxin, soften hardness and dissipate nodules, promote diuresis and relieve strangury.
Indications
Used for goiter (thyroid enlargement) and nodular swelling, difficult urination, strangury with pain, bronchitis, enteritis and dysentery, as well as chronic constipation, among others.
Modern Pharmacology
Antitumor: Studies have shown that its organic acid extract exhibits significant cytotoxic activity against HeLa cells. Immunomodulatory: The sulfated polysaccharides it contains are important immunomodulators. Antioxidant: The polysaccharide components effectively scavenge free radicals. Cardiovascular protection: Rich in dietary fiber, it helps lower blood lipids and blood pressure. Hypoglycemic: Studies indicate that its polysaccharides have a blood glucose‑lowering effect. Anticoagulant: Possesses certain anticoagulant activity. Laxative (moistening intestines and relieving constipation): The crude fiber it contains absorbs water, softens stools, and stimulates the intestinal wall.
Ingredients
Polysaccharides: Agar is the main component. Additionally, it contains sulfated polysaccharides with various biological activities, accounting for approximately 30% of the dry weight of the thallus. Proteins/Pigments: R‑phycoerythrin. Fatty acids: Rich in eicosapentaenoic acid (EPA), arachidonic acid (both unsaturated fatty acids), palmitic acid, stearic acid, oleic acid, etc. Others: Contains boric acid, lectins, prostaglandins, and various minerals such as potassium and iodine.
Usage & Dosage
Internal use: 15–30 g in decoction. For daily health maintenance and dietary therapy, it is recommended to consume 15–20 g per serving. External use: Appropriate amount, crushed and applied topically to the affected area. Dietary therapy: Can be eaten cold in a salad, stir‑fried, or cooked in soup. For example, cold dragon‘s beard seaweed salad is a commonly used dietary therapy for mumps (parotitis).
Contraindications
1. Contraindicated populations: Use with caution in cases of spleen‑stomach deficiency cold; those with a cold constitution should eat little or avoid it; those with loose stools or prone to diarrhea should consume less due to its laxative effect. 2. Precautions: Not suitable for patients with gout (as it is high in purines). Wash thoroughly before consumption; blanching in boiling water can help remove excess salt and impurities. Do not overconsume, as it may cause gastrointestinal discomfort.
Selected Formulas
1. For treating tracheitis (bronchitis) (Source: Chinese Marine Materia Medica Dictionary) Ingredients: Fengweicai (Dragon‘s Beard Seaweed) 15 g, Mahuang (Ephedra) 6 g, Xingren (Apricot Seed) 10 g, Madouling (Aristolochia) 15 g, Jiegeng (Platycodon) 10 g, Gancao (Licorice) 6 g. Usage: One dose per day, decoct in water and take orally, twice a day. 2. For treating internal heat with profuse phlegm, goiter (scrofula) and nodular swelling (Source: Chinese Medicinal Marine Organisms) Ingredients: Jiangli (Gracilaria), Ludongcao (Pelvetia), Xiakucao (Prunella) – 15 g each, Muli (Oyster Shell) 30 g. Usage: Decoct in water and take orally. 3. For treating goiter (scrofula) and nodular swelling (Source: Chinese Marine Materia Medica Dictionary) Ingredients: Fengweicai 20 g, Kunbu (Laminaria) 15 g, Haizao (Sargassum) 15 g, Gefen (Clam Shell Powder) 20 g. Usage: One dose per day, decoct in water and take orally, twice a day. 4. For treating goiter (scrofula) and nodular swelling (Source: Chinese Marine Materia Medica Dictionary) Ingredients: Jiangli 15 g, Biejia (Soft‑shelled Turtle Shell) 15 g, Muli 15 g. Usage: One dose per day, decoct in water and take orally, twice a day. 5. For treating goiter (scrofula) and nodular swelling (Source: Chinese Dietary Materia Medica) Ingredients: Jiangli 15 g, Haipiaoxiao (Cuttlebone) 6 g, Haihaozi (Sargassum) 10 g, Xiakucao 12 g. Usage: One dose per day, decoct in water and take orally, twice a day. 6. For treating difficult urination (strangury) (Source: Chinese Medicinal Marine Organisms) Ingredients: Jiangli 15 g, Cheqiancao (Plantain Herb) 15 g. Usage: Decoct in water and take orally. 7. For treating dysentery (Source: Chinese Marine Materia Medica Dictionary) Ingredients: Fengweicai 20 g, Huangbai (Phellodendron) 12 g, Huanglian (Coptis) 6 g. Usage: One dose per day, decoct in water and take orally, twice a day. 8. For treating dysentery, enteritis, and diarrhea (Source: Zhejiang Medicinal Flora) Ingredients: Appropriate amount of whole Jiangli (Gracilaria) herb. Usage: Decoct in water, add sugar, and take orally.
Daily Consumption
1. Cold Dragon’s Beard Seaweed Salad (Most Common) Ingredients: Dried dragon’s beard seaweed 15–20 g (or fresh 30–50 g), minced garlic, vinegar, light soy sauce, sesame oil, salt, sugar, chili oil (optional) – to taste. Preparation: Soak the dried seaweed in cold water for 30 minutes until softened, wash, and remove any impurities. Blanch in boiling water for 1–2 minutes, then drain and rinse with cold water. Add minced garlic, vinegar, light soy sauce, sesame oil, salt, sugar, and other seasonings. Mix well. Action: Clears heat and resolves toxin, softens hardness and dissipates nodules. It is traditionally used as an adjunctive treatment for mumps (parotitis). 2. Scrambled Eggs with Dragon’s Beard Seaweed Ingredients: Fresh dragon’s beard seaweed 50 g, 2–3 eggs, salt, chopped scallion – to taste. Preparation: Wash the fresh seaweed, cut into sections, blanch, and drain. Beat the eggs, add salt, and mix well. Heat oil in a wok, pour in the egg mixture and stir‑fry until half cooked. Add the seaweed sections and chopped scallion, then stir‑fry until fully cooked. Action: Supplies protein and iodine, enhances immune function. 3. Dragon’s Beard Seaweed and Tofu Soup Ingredients: Dried dragon’s beard seaweed 15 g, soft tofu 200 g, shredded ginger, salt, sesame oil – to taste. Preparation: Soak and wash the dried seaweed, cut the tofu into cubes. Bring water to a boil, add shredded ginger and tofu, cook for 5 minutes. Add the seaweed and cook for another 2–3 minutes. Season with salt and sesame oil. Action: Clears heat and promotes diuresis. Suitable for difficult urination and edema.
Medicinal Parts
dried thallus
Selection & Storage
Dried product: After harvesting, wash, dry in the sun or by oven, then store in a sealed container in a cool, dry place, protected from moisture and insects. Fresh product: Use fresh or store in a refrigerator for short‑term preservation.