紅花苜蓿.Red Clover

Botanical Name:   Trifolium pratense  

Common Names:   Beebread, Cow Clover, Cow Grass, Meadow Clover, Purple Clover  


Red clover, a wild plant used as grazing food for cattle and other livestock, has also been used medicinally to treat a wide array of conditions. These have included cancer, mastitis (inflammation of the breast), joint disorders, jaundice, bronchitis, spasmodic coughing, asthma, and skin inflammations, such as psoriasis and eczema. Red clover is thought to "purify" the blood by promoting urine and mucous production, improving circulation, and stimulating the secretion of bile. Recently, specific chemicals in red clover -- known as isoflavones -- have been isolated and tested for their effectiveness in treating a variety of conditions. Although isolated isoflavone products are very different from the whole herb, they have shown promise in the treatment of a number of conditions associated with menopause, such as hot flashes, cardiovascular health, and the bone loss associated with osteoporosis. 

Plant Description:

  Red clover is a perennial herb that commonly grows wild in meadows throughout Europe and Asia, and has now been naturalized to grow in North America. The red flowers at the end of the branched stems are considered to be the source of its medicinal properties and are usually dried for therapeutic use.

    Red Clover (Trifolium pratense) - Red clover is a perennial which belongs to the family of Leguminosae. Other names for red clover are cow clover, purple clover and bee-bread. It's a perennial with trifoliate leaves and pink to red flowers. Red clover has hairy stemmed to prevent ants from easily climbing the stems. 

The plant derives its name in part from its flowers, which are fragrant and can range in color from white to a dark red. 

Red clover is a wild and very common plant. Red clover is abundant throughout Europe, Central and Northern Asia from the Mediterranean to the Arctic Circle. Red clover has been naturalized to grow in North America. As the other name, "bee-bread" suggests, red clover produces a honey but far less than white clover. 

Red clover also grows well in grazing land where it binds nitrogen into the soil. Planting red clover will improve the soil because the roots have special nodules that house nitrogen-fixing bacteria. These bacteria can grab nitrogen from the air in the soil and make it available to the plant. When the red clover plant decomposes it makes that nitrogen available to the soil.




Characteristics of Red Clover:

 Red clover (Trifolium pratense L.) is grown throughout the northeastern U.S. for forage production and use in rotations for soil improvement. It is adapted to areas where summer temperatures are moderate and adequate moisture is available throughout the growing season. Unlike alfalfa, red clover will grow moderately well on slightly acid soils. However, maximum yields are obtained when the pH is 6.0 or higher. 

Red clover is a short-lived perennial, which usually produces two or three hay crops per year. It is characterized by rapid spring growth and low winterhardiness which contributes to its short-lived nature. 

The growth habit of red clover varies from erect to prostrate. Numerous stems with large trifoliate leaves arise from the crown region each year. Red clover has a thick tap root which grows to a length of 24-36 inches. Lateral roots which arise from the tap root are mainly concentrated in the upper 5 inches of the soil. Small ovoid, pinkish, nitrogen fixing nodules can be found on the lateral roots if it is actively incorporating atmospheric nitrogen into protein nitrogen. 

The isoflavones in red clover are used primarily to alleviate the symptoms of female menopause. Red clover is also used to support the prostate gland and normal urinary tract function in males, to promote general prostate health and is also cited to support normal cholesterol levels.  

Red clover isoflavones are generally recommended for relief of menopausal symptoms and for general health and well-being of postmenopausal women. Red clover has also been cited to help maintain normal blood cholesterol levels and to maintain a healthy urinary tract and prostate.  

Due to recent studies red clover extracts are currently used more for their phytoestrogenic properties. However, red clover has been used historically by Orientals and Europeans as a medicinal herb for a variety of purposes. In folk medicine, red clover has been used to promote lymph flow and support immune system function. It is suggested to provide a mild sedative effect that can relax and relieve muscle cramping and nervousness. Red clover is also known as a blood purifier and for improving the overall health of the liver. It may also act as a digestive aid and stimulator of digestive fluids and bile production.  

Traditionally, the blossoms from the red clover plant were used as a tonic taken in the spring to promote good health and peace of mind. Red Clover contains small amounts of silica, choline, calcium and lecithin, all important  for normal body function. Red Clover help with muscle relaxation and also is a good expectorant. It is an old-time topical remedy for eczema. 

Common Uses of Red Clover in herbal medicines: Blood purification, alterative, antineoplastic, skin ailments, wounds; antispasmodic, bronchitis, coughs. Red Clover combines well with other herbs; Burdock, Stillinngia, Golden Seal, etc. Believed to be soothing to nerves, ulcers, psoriasis, eczema, and gentle enough for children. 

Red Clover grows in Europe and North America. The plant grows best where soils are rich in calcium, phosphorus, and potassium. The flowering tops are used medicinally.  In Europe, Red Clover is widely cultivated and used as a tonic and a salad herb. Red Clover is used by honey makers to add a mild, sweet taste to their honey. Like Alfalfa, it serves as common fodder for domestic animals. Herbalists have long prized this herb for its' traditional use as a blood purifier, expelling toxins from the bloodstream. Primary chemical constituents of Red Clover include phenolic glycosides (salicylic acid), essential oil (methyl salicylate), sitosterol, genistiene, flavonoids, salicylates, coumarins, cyanogenic glycosides, silica, choline, and lecithin. Red Clover also contains Vitamin A, Vitamin C, B-complex, calcium, chromium, iron, and magnesium. Researchers from the National Cancer Institute (NCI) have found anti-cancer properties in this herb. 

Flavonoids are 3-ring phenolic compounds consisting of a double ring attached by a single bond to a third ring. In leaves they block far ultraviolet (UV) light (which is highly destructive to nucleic acids and proteins), while selectively admitting light of blue and red wavelengths which is crucial for photosynthesis. Flavonoids include water soluble pigments (such as anthocyanins) that are found in cell vacuoles. Water soluble flavonoids (mostly anthocyanins) are responsible for the colors of many flowers and can range from red to blue, depending on the pH of the watery sap in the vacuoles. The common garden shrub called hydrangea (Hydrangea macrophylla ) produces showy clusters of white, pink, red or blue flowers depending on the pH of the soil. 




Duckweeds of the family Lemnaceae contain many kinds of flavonoids, including red anthocyanins in some species. They are often difficult to identify because they are such reduced flowering plants with relatively few characteristics. Using two-dimensional paper chromatography, duckweed species have been separated and identified by their unique flavonoid content. When viewed under UV light. 



This is the basic flavonol skeleton, with the -OH at position 3 and the =O at position 4. It also differs from flavanols by having a double bond between carbons 2 and 3 on the C ring. 

Flavones:  Flavones are like flavonols, without the "-ol." In other words, there is no longer an -OH group at position 3 on the central ring.



ic flavanone skeleton retains the =O, which makes it an "-one." Many flavanones occur as glycosides; for example, hesperitin (aglycone) and hesperidin (glycoside) occur in citrus along with naringenin  (--->)

Isoflavones: Isoflavones (also known as isoflavonoids) are very similar to flavones, except the B ring is attached to position 3 of the C ring, rather than to position 2 as in the flavones:



To the left is the basic flavone skeleton, with the B ring attached to position 2

of the central ring. On the right is the isoflavone skeleton,which is exactly the same as the flavone skeleton but with the B ringa ttached to position 3. "Iso" is short for "isomer." 




Here is the isoflavone Genistein, found in Red clover, Alfalfa, Peas, Soy & other legumes. It consists of the basic isoflavone skeleton with -OH groups attached at positions 5, 7, and 4'. Genistein is protective against breast, prostate, and colon cancers and can help with hot flashes and osteoporosis prevention. 


 Seeds are reported to contain trypsin inhibitors and chymotrypsin inhibitors. Green forage of red clover is reported to contain: 81% moisture, 4.0% protein, 0.7% fat, 2.6% fiber, 2.0% ash. Hay of red clover contains 12.0% moisture, 11.8% protein, 2.6% fat, 27.2% fiber, and 6.4% ash. On the basis of more than 500 analyses, Miller (1958) reported the hay contained on a moisture free basis: 8.3–24.7% protein (avg 14.9%), 1.0–6.6% fat (avg. 2.9%), 12.5–39.3% crude fiber (avg. 30.1%), 3.1–14.0% ash (avg. 7.9), and 33.4–59.1% N-free extract (avg. 44.2). For green red clover forage he reported 12.4–34.87. protein (avg. 18.2), 3.2–5.9% fat (avg. 4.0%), 12.7–30.8% crude fiber (avg. 24.2), 7.0–13.6% ash (avg. 8.8), and 37.1–49.7% N-free extract (avg. 44.8%). The hay (dry matter averaging 87.7%) contained 0.97–2.29% Ca (avg. 1.61), 0.09–0.45% P (avg. 0.22), 0.57–2.67% K (avg. 17.6%), 0.24–0.81% Mg (avg. 0.45%), 0.001–0.185% Fe (avg. 0.013%), 9.9–17.6 ppm Cu (avg. 11.2 ppm), and 24.9–120.8 ppm Mn (avg. 65.6). The green forage contained 0.58–3.21% Ca (avg. 1.76), 0.24–0.53% P (avg. 0.29), 1.49–2.94% K (avg. 2.10%), 0.36–0.57% Mg (avg. 0.45), 0.016–0.032% Fe (avg. 0.03), 7.3-10-3 ppm Cu (avg. 8.8 ppm), 121–464 ppm Mn (avg. 159 ppm). The leaf-protein concentrate (59% protein) contains 6.4% arginine, 2.5% histidine, 5.4% threonine, 1.7% tryptophan, 9.5% leucine, 5.3% isoleucine, 1.7% methionine, 6.87. lysine, 6.1% phenylalanine, and 6.8%. valine. Estrogenic disorders have been reported in cattle grazing largely on red clover, apparently due to activity of the isoflavones formononetin, biochanin A, and to some small extent daidzein and genistein. the flowers contain a number of phenolic compounds: daidzein, genistein, isotrifolin, isorhamnetin, pratol, pratensol, trifolin, and an antifungal compound trifolirhizin. They also contain coumaric acid, hentriacontane, heptacosane, myricyl alcohol, and b-sitosterol. On a dry basis flowers yield 0.028% of an oil containing furfural (Duke, 1981a).  

Red clover is available in a variety of preparations, including teas, tinctures, tablets, capsules, liquid extract, and extracts standardized to specific contents. It can also be prepared as an ointment for topical application.