GINGKO

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Herbal Monograph

Herb: GINKGO LEAF    (Ginkgo Biloba; Coniferales)

Other Names:  Maidenhair Tree  (15)  ;  Maidenhair  (16)

Character/Energetics:  Leaves and Nuts–sweet, bitter, astringent, neutral    (15) 

Meridians/Organs/Body Parts affected:

Parts used:  Leaves and Seeds (Nuts)  (6) (15)–see both sources for extensive notes on ginkgo seed/nut        

Harvesting & Identification:  Tree begins to flower at 20-30 years of age.  Seeds become fleshy and plum-like round, light green or yellow, 2.5-3 cm diameter, containing a two-edged edible nut.  When ripe, exudes an intense foul odor.  Tree reaches 30-40 m high, 1 m. diameter.  Roughly grooved bark, fan-shaped leaves with bifurcated ribs (“biloba” = two lobes).  Fresh green to golden yellow in autumn.  Indigenous to China, Japan, Korea.  (2);  Leaves— Harvest in summer. Nuts— The seeds, bai gou, are only found on the female plant. (15) Likes a temperate climate.   (16);

A living fossil more than 200 million years old.  Most commercial leaf is from plantations in South Carolina, France and China.    (61)

As with many other trees, the leaves change color around September, from a dark, rich green to a golden yellow.  Considerable changes in levels of active principles result (cf. Active Constituents, below, same source).   (63)

Active Constituents:  Flavonoids:  incl. monosides, biosides and triosides of quercetin, isorhamnetins, 3′-O-methylmyristicins, kaempferol, to some extent estered with p-cumaric acid;  Bioflavonoids:  incl. ametoflavone, bilobetin, 5-methoxybilobetin, ginkgetin, isoginkgetin;  Proanthocyanidins;  Trilactonic diterpenes: ginkgolide A, B, C;  Trilactonic sesquiterpenes (bilabolide).   (2)

          Flavone glycosides (including ginkgolide), bioflavones, sitosterol, lactones,  anthocyanin  (15)

          The principal constituents found in a leaf extract are three flavone glycosides (quercetin, isorhamnetin  and  luteolin) and bioflavones (ginkgetin,  isoginkgetin and bilobetin).  In addition the leaves contain two lactones, sitosterol and an anthocyanin.  As in the case of crataegus and many other medicinal plants, a mixture of active principles is present, with flavonoids predominating.  (16)

          Levels of active principles differ in yellow/gold leaves, as compared to pre-autumn green leaves;  in the gold, the anti-oxidant flavonoids reach their highest levels, but the ginkgolides and bilobalides reach highest levels just before the color change, and drop off to lowest levels when the leaves have turned yellow and are falling from the tree (cf. Joniris R.D. note, below, in Actions).   (63)

Actions:  Inhibits development and acceleration of cerebral edema;  reduction of retinal edema and of cellular lesions in the retina;  inhibits age-related decrease of muscarinergic cholinoceptors;  also stimulates choline uptake in the hippocampus.  Improves concentration and memory deficits resulting from peripheral arterial occlusion.  In animal experiments, improves hypoxic tolerance, glucose utilization, membrane stabilization;  reduction of blood viscosity also noted.  The ginkgolide B component has a potent inhibitory effect on the platelet-activating factor (PAF) by displacing it from receptor sites.  Thus extracts of the herb could interact with antithrombotic therapy.   (2); relaxes blood vessels, circulatory stimulant    (15);  

Most current research focuses on its use in peripheral circulation as well as to the brain, esp. in the elderly.  Most studies involve an extract called EGb-761.  Effects attributed to flavone glycosides and ginkgolides, which inhibit platelet-activating factor involved in development of inflammatory, cardiovascular and respiratory disorders.  Ginkgo also has strong antioxidant activity in the brain, central nervous system and cardiovascular system.  Joniris RD Note — [The likelihood of Alzheimer’s is known to be reduced by regular dietary supplementation of Vitamin E;  further, its onset is also delayed thereby, and these actions have been attributed to E’s antioxidant activity in the memory-linking center of the brain.  Speculate that in a diet somewhat deficient in E, ginkgo’s antioxidant activity in the brain can help compensate, and similarly reduce likelihood of Alzheimer’s and slow its onset.]    (61)

Flavonoids act as free radical scavengers.  Both free radical formation and PAF can disrupt vascular membranes, resulting in increased vascular permeability.   (64)

Joniris R.D. Note:  [The flavonoids and proanthocyanidins have a toning effect on blood vessels, whereas the ginkgolides alleviate peripheral arterial occlusion (via a blood-thinning effect), improving circulation in the brain (and elsewhere) with resultant effects on concentration and memory.  Yet the ginkgolides also inhibit platelet aggregation, which can exacerbate bleeding disorders.  Therefore, given the variation in the levels of these respective principles in pre- and post- autumn leaves, harvesting practices should reflect their desired use.  For patients with bleeding disorders or currently taking anti-thrombotic or similar medications, whose side effects can be exacerbated by the PAF-inhibiting principle in ginkgo leaf, extracts should be from leaves harvested late;  also for maximum effectiveness in treatment of varicose veins or other vascular disorders.  On the other hand, if there is little danger of resulting bleeding disorder, the pre-autumn leaves are most effective for improving cognitive brain functions. 

Therefore, Joniris Herbals utilizes green-leaf ginkgo in Brain Tonic and gold-leaf ginkgo in Circulation Tonic]–note derived largely from (63).

Conditions & Uses:  Treats vertigo and tinnitus of vascular causation, brain dysfunctions resulting in dizziness, headache, anxiety.   (2);   

The 24 to 1 leaf extract is now a popular herbal product for a wide variety of vascular problems…. increasing vascular circulation to the brain for the treatment of dementia and possibly Alzheimer’s disease. (6); 

Part of the herbal repertoire only since the 1980s, the leaves are used for circulatory diseases, they are particularly good at improving blood flow to the brain. Research has shown that ginkgolide can be effective as standard pharmaceutical drugs in treating severely irregular heartbeats.  The leaves are also used for varicose veins, hemorrhoids, and leg ulcers. (15)

European studies have shown ginkgo leaf to correct erectile failure in 50% of patients.   (22)

              Ginkgo  has  proved  an  important  medicinal plant in the treatment of  circulatory disorders. It may    GINKGO LEAF    (Ginkgo Biloba; Coniferales)

Conditions & Uses: (cont)

be called an angio-activator….

The extract from fresh leaves is marketed as Tebonin (Schwabe).  A considerable literature provides experimental and clinical evidence that Tebonin achieves vasodilation and improved blood flow particularly in the region  of  deeper‑seated  medium  and small arteries. There is an increased flow rate in the capillary vessels and end‑arteries. The indications arise from this. They are primarily 1st and 2nd  degree  peripheral circulatory disorders.  Walking distance is definitely increased due to alleviation of intermittent claudication (limping).  Subjective improvement has been reported in Raynaud’s disease and other conditions involving vascular spasm.  

On the other hand, Tebonin also has an effect on disorders of cerebral circulation, particularly cerebral arteriosclerosis. Dizziness is much improved in elderly subjects, and other symptoms such as loss of memory also respond well. Ginkgo has shown itself to be a geriatric plant drug of particular value. Significant improvement in mental states, emotional lability, difficulty in remembering and the tendency to tire easily has been reported by various authors. It also appears that ginkgo is a drug that can still help in diabetic angiopathy, a condition notoriously difficult to treat.

A third indication are diseases affecting the veins, as the vasodilator effect is not limited to the arterioles but extends also to the capillaries and venoles. Tebonin therefore also has a good effect on varicose conditions, postthrombotic syndrome and leg ulcers, particularly if combined with heptaminol and a rutoside as in Veno-Tebonin. The French ginkgo preparation Ginkor (Laboratories Beaufor) is similar in composition and also recommended for varices, circulatory disorders and haemorrhoids.

Quite large doses appear to be needed to get an adequate effect in serious cases, particularly if the drug is given by mouth. There is no problem with this as it is well tolerated and no toxic side effects have been reported. 

Ginkgo has proved a valuable new edition to the herbal armamentarium for vascular diseases. It should be noted that different plants have different points of attack. Crataegus and arnica act mainly on the coronary vessels, garlic and ginkgo on the peripheral vessels. All of them also have an effect on cerebral blood flow, though this appears to be most marked with ginkgo. Maidenhair also has a demonstrable effect on the venous system and is used to treat conditions such as varicose veins. It therefore marks the transition to drugs acting purely on the venous system, such as horsechestnut.   (16)     

Re: Ginkgo Nuts: In China, the seeds, called bai gou, are considered to act on the lung and kidney acupuncture meridians and are traditionally used for asthmatic disorders and chesty coughs with thick phlegm. They also have a tonifying effect on the urinary system, so are used for incontinence and excessive urination.  (15)

Traditionally used for the brain and for lung disorders, cough and asthma, and diarrhea.  The leaf paste is applied externally to sores and to remove freckles.  Improves oxygen metabolism in the brain with corresponding improvements in short-term memory, attention span, and mood in early stages of Alzheimer’s.  Studies show some improvement of dementia associated with Alzheimer’s in later stages.    (61)

Significantly inhibited bronchial constriction in asthmatic patients for up to six hours after they were administered an asthma-causing allergen.  PAF plays a central role in airway hypersensitivity and bronchial constriction noted in asthma.   (64)

Combinations:  Combines well with horse chestnut   (1b); Combine with wood betony as a tonic, or add linden and hawthorn for circulatory problems.   (15)

Precautions:  Occasional mild GI complaints.  Extremely rare allergic skin reactions have been observed.  Some patients prove to be hypersensitive, resulting in spasms, cramps, and in cases of acute toxicity, atonia and adynamia.  Protect from light and moisture.   (2)

Ginkgo and blood thinners– Interactions between blood‑thinning herbs and pharmaceutical medications with the same action present perhaps the greatest risk of drug‑herb interactions in modern practice. The risk is due to the gravity of the underlying condition that requires a blood‑thinner, and to the fragile dose range and serious side effects of the pharmaceutical drugs themselves. The drugs must be given in high enough doses to prevent the formation of  life-threatening clots, but can cause serious and life‑threatening bleeding disorders if given in too high a dose. A blood thinning herb can act like “the straw that broke the camel’s back” by, thinning the blood enough to allow the drug to provoke a serious bleeding disorder. The risk is probably greatest with heparin, warfarin, and coumarin derivatives, but recent anecdotes indicate that interactions may also occur between blood thinning herbs and such mild pharmaceutical blood‑thinners as aspirin….(see Medical Herbalism, Summer 1997, pg.16 for remainder of article)    (30)

The danger of taking ginkgo and blood-thinning prescription meds at the same time is that blood-thinners such as warfarin inactivate vitamin K, the vitamin essential to liver production of the protein fibers that form the net-like substrate of a blood clot;  whereas ginkgo inhibits platelet activity.  In normal clotting function, the protein net forms at a breach in a blood vessel wall, and the platelets clump together and get caught in the net, starting the clot, which builds up like a clogged sink drain.  Taking an anticoagulant and an anti-PAF at the same time therefore involves more risk of hemorrhage or bleeding disorder than either alone.  If you feel a strong need to take the herb and the drug at the same time, have your doctor measure your bleeding time regularly to be certain it doesn’t exceed a healthy range.    (1c)    Joniris R.D. Note — [our opinion is that the “blood thinning” herbs such as gingko are superior to the standard prescription meds in several respects:  herbs have much fewer bad side effects, and their beneficial activities are numerous, because they represent a synergistic complex of biologically active principles, whereas prescription medicines are usually only a single chemical.]

Ginkgolic acid potentially toxic.  Rare gastric upset, headache or skin allergy.    (61)

Tincturing Process: Vita Mix (Speed 7):  Fill VM container half-full. Process 2 minutes. 60% alcohol  (1a)

Applications: 

                Fluid extract–an extract of the fresh leaves is marketed in Europe for treating arteriosclerosis in the elderly and for diseases of the peripheral circulation.

              Tincture–Combine with other cardiovascular herbs, such as greater periwinkle and limeflower, for circulatory problems, or with king’s clover for venous disorders. 

                Infusion–50 g dried leaves to 500 ml water… for arteriosclerosis and varicose conditions. Use as a wash for varicose ulcers or hemorrhoids.  (15)

Divination:

Dosage:  Avg. daily dose is 120 mg dried extract in 2-3 doses orally;  parenteral dose is 50-100 mg daily.  In Chinese medicine, daily dose is 3-6 g. of leaves in infusion.   (2)

               Large doses necessary in serious cases, particularly if the drug is given by mouth.   (16)

At least 40 mg standardized extract daily.    (61)

General Notes:  Dating back at least 200 million years, the wild maidenhair tree has probably been extinct for centuries, but cultivated trees survived in Far Eastern temple gardens. A deciduous conifer with separate male and female forms, the tree was introduced into Europe in 1730 and became a favorite ornamental. Since the 1980s, Western medical interest in the plant has grown dramatically since its potent actions on the cardiovascular system were identified.  (15) 

Pollen is wind‑borne, like that of conifers.  The peculiar leaf shape is considered to represent unity within duality (Goethe, West-Oestlicher Diwan).  (16)

Relatively new in herbal medicine, used in China since 15th c.  Must be used for 6-8 weeks before results are evident.    (61)

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References:

(1a)Joniris “Ginkgo Tincture” file

(1b) Joniris Herbals Research Data, Horse Chestnut Monograph

(1c) Joniris Herbals Research Data, “The Herb-Drug Mix” by Robert Rountree, M.D., Herbs for Health, Jul/Aug ’99, pgs. 52-54

(2) PDR for Herbal Medicines (Medical Economics Co., 1998), pgs. 871-72

(6) Planetary Herbology by Michael Tierra, C.A., N.D., pg. 345

(15) The Complete Medicinal Herbal by Penelope Ody, pgs. 64, 151

(16) Herbal Medicine by Rudolf Weiss, M.D., pgs. 178-179

(22) Herbs and Herbal Formulas (booklet) by Mark Hershiser, p. 9

(30) Medical Herbalism, Vol. 9, No. 2, Summer 1997

(61) 101 Medicinal Herbs by Steven Foster, pgs. 100-101

(63) Ginkgo, Elixir of Youth by Christopher Hobbs, p. 56

(64) Ginkgo Biloba, The Amazing 200-Million Year-Old Healer by Frank Murray, p. 12

GINKGO LEAF    (Ginkgo Biloba; Coniferales)

Distinctions between Green and Gold Leafs

Active Constituents:  Flavonoids:  incl. monosides, biosides and triosides of quercetin, isorhamnetins, 3′-O-methylmyristicins, kaempferol, to some extent estered with p-cumaric acid;  Bioflavonoids:  incl. ametoflavone, bilobetin, 5-methoxybilobetin, ginkgetin, isoginkgetin;  Proanthocyanidins;  Trilactonic diterpenes: ginkgolide A, B, C;  Trilactonic sesquiterpenes (bilabolide).   (2)

          Flavone glycosides (including ginkgolide), bioflavones, sitosterol, lactones,  anthocyanin  (15)

          The principal constituents found in a leaf extract are three flavone glycosides (quercetin, isorhamnetin  and  luteolin) and bioflavones (ginkgetin,  isoginkgetin and bilobetin).  In addition the leaves contain two lactones, sitosterol and an anthocyanin.  As in the case of crataegus and many other medicinal plants, a mixture of active principles is present, with flavonoids predominating.  (16)

Synopsis:

  Green leaf – high in ginkgolides and bilobalides (improves circulation to brain

  Gold leaf – high in flavonoids and proanthocyanidins (toning effect on blood vessels)

         

           Levels of active principles differ in yellow/gold leaves, as compared to pre-autumn green leaves;  in the gold, the anti-oxidant flavonoids reach their highest levels, but the ginkgolides and bilobalides reach highest levels just before the color change, and drop off to lowest levels when the leaves have turned yellow and are falling from the tree (cf. Joniris R.D. note, below, in Actions).   (63)

Flavonoids act as free radical scavengers.  Both free radical formation and PAF can disrupt vascular membranes, resulting in increased vascular permeability.   (64)

Joniris R.D. Note:  [The flavonoids and proanthocyanidins have a toning effect on blood vessels, whereas the ginkgolides alleviate peripheral arterial occlusion (via a blood-thinning effect), improving circulation in the brain (and elsewhere) with resultant effects on concentration and memory.  Yet the ginkgolides also inhibit platelet aggregation, which can exacerbate bleeding disorders.  Therefore, given the variation in the levels of these respective principles in pre- and post- autumn leaves, harvesting practices should reflect their desired use.  For patients with bleeding disorders or currently taking anti-thrombotic or similar medications, whose side effects can be exacerbated by the PAF-inhibiting principle in ginkgo leaf, extracts should be from leaves harvested late;  also for maximum effectiveness in treatment of varicose veins or other vascular disorders.  On the other hand, if there is little danger of resulting bleeding disorder, the pre-autumn leaves are most effective for improving cognitive brain functions. 

Therefore, Joniris Herbals utilizes green-leaf ginkgo in Brain Tonic and golf-leaf ginkgo in Circulation Tonic]–note derived largely from (63).

Cayuga Herbal Monograph…footnotes

(2) PDR for Herbal Medicines (Medical Economics Co., 1998), pgs. 871-72

(15) The Complete Medicinal Herbal by Penelope Ody, pgs. 64, 151

(16) Herbal Medicine by Rudolf Weiss, M.D., pgs. 178-179

(63) Ginkgo, Elixir of Youth by Christopher Hobbs, p. 56

(64) Ginkgo Biloba, The Amazing 200-Million Year-Old Healer by Frank Murray, p. 12