商品描述

銀杏(萃取液)

History:

Ginkgo has been used as food and medicine for more than 4,000 years, and traditional Chinese herbalists still rely on the plant for the treatment of asthma, bronchitis, and brain disorders. Often called a "living fossil", the magnificent Ginkgo biloba tree itself is the last survivor of its botanical family. In fact, it is the oldest living tree species known to humankind, and individual trees may live as long as 1,000 years。

Research Findings:

With hundreds of published scientific studies to document its complex and varied effects, Ginkgo is among the world's best studied herbs, and the evidence continues to grow.Current trials are exploring its potential in the treatment of intermittent claudication,asthma, cataracts,drug-resistant depression,hearing loss, head injuries, and a variety of other conditions. Most trials use a ginkgo extract standardized to contain  ginkgo flavone glycosides.

Specific Studies

Clinical Study:

In a placebo-controlled, double-blind, 52-week trial involving 202 patients with mild-to-severe dementia associated with Alzheimer's disease or multi-infarct dementia, stabilization or improvements were seen in a number of daily living and cognitive functions.The researchers stated that benefits could be equated with a "six month delay in the progression" of Alzheimer's disease.

Clinical Study:

In a placebo-controlled, double-blind study involving 166 patients over the age of 60, results "confirmed the efficacy of ginkgo extract in cerebral disorders due to aging" after 3 months of treatment. Patients most affected by disease appeared to benefit most from ginkgo.

Clinical Study:

Significant improvements in mental performance, including short-term memory and concentration,were seen after 6 weeks of treatment with standardized ginkgo extract in a placebo-controlled double-blind trial involving 90 patients with cerebral insufficiency.

Meta-Analysis:

In five placebo-controlled trials,there was a highly significant increase in pain-free walking distance after treatment with standardized ginkgo extract in patients with peripheral arterial disease. (Schneider,1992)

Safety：

Gingko appears to be extremely safe and is well tolerated by most people. No major adverse effects or drug interactions were noted in any clinical trials, and side effects of any kind are rare.The most common side effects are mild gastrointestinal discomfort and headache. However,very large doses may cause diarrhea, nausea, vomiting, and restlessness.

Using Ginkgo：

Almost all of the clinical research on ginkgo has been done on one form of standardized extract, a 50:1 concentrated extract. Standardization ensures that an extract contains a consistent level of active compounds, and ginkgo extract is standardized to contain ginkgo flavone glycosides. In the clinical studies, the effective dose of the standardized extract was three times a day, a total of ginkgo extract a day.

Unstandardized Ginkgo extracts are available in tincture, capsule, and tablet form,but there is no clinical research to support the effectiveness of these preparations.

The officially recommended usage levels, and those used in research studies are:

Standardized extract capsules,tablets,or tincture:In clinical trials, effective dose was three times a day of extract, standardized to contain  ginkgo flavone glycosides.

ACTION:

Inhibition of PAF (platelet activating factor), Antioxidant (free-radical scavenging), Reduction of blood viscosity (causes an increase in the rate of blood flow), Neuro-protection, Stabilization of capillary permeability.

INDICATIONS:

Ginkgo biloba is a plant extract used to alleviate symptoms associated with cognitive deficits, e.g., decreased memory performance, lack of concentration, decreased alertness, tinnitus, and dizziness. A treatment period of 4 to 6 weeks is needed before a pronounced effect could be expected.

PAF antagonist: PAF, a plasmalogen is a major mediator of hypersensitivity, acute inflammatory reactions and anaphylactic shock.

Platelet activating factor (PAF)

In hypersensitive individuals, cells of the polymorphonuclear (PMN) leukocyte family (basophils, neutrophils and eosinophils) macrophages, and monocytes are coated with IgE molecules that are specific for a particular antigen (e.g., pollen, dust, insect stings, certain molecules in foods). Subsequent re-exposure to the antigen and formation of antigen-IgE complexes provokes the synthesis and release of PAF. PAF is not stored in the body but only synthesized and released when PMNs are stimulated.

When PAF is released, they cause; platelet aggregation, edema, PMN cell chemotaxis, contraction of smooth muscle, reduction of coronary circulation, hypertension, bronchoconstriction, increase permeability of cutaneous vessels, raised haematocrit, and secretion of lysosomal enzymes.

Ginkgolide B blocks the binding of PAF to membrane receptors.

Free radical scavenging: Ginkgo extract stimulates prostaglandin synthesis and inhibits lipid peroxidation in the cell membrane (Pincemail and Deby, 1991). Pincemail et al. (1987,1989) were also able to show that ginkgo possesses superoxide dismutase activity. Superoxide dismutase (SOD) is a group of metalloenzymes that catalyze a disproportionation reaction in which superoxide is reduced to hydrogen peroxide according to the following equation:

O2- + O2- + 2H+ -> H2O2 + O2

Rate of blood flow: The flow of blood is mainly influenced by the haematocrit, plasma viscosity, the aggregation and flexibility of the erythrocytes. In therapeutic concentrations of 35 to 70µg/10ml, ginkgo extract produced a significant reduction in erythrocyte aggregation in patients with vascular disease involving abnormal erythrocyte aggregation and flexibility.

Ginkgo biloba extracts EPG 246,G328 and G320:

Chemical definition:

Mixture of Ginkgo flavonol glycosides, Ginkgo terpene lactones and Proanthocyanidins.

Assay:

l Linnea EPG 246: 24% Ginkgo flavonglycosides, 6% Terpene lactones (Ginkolides and bilobalides balanced as per German monograph)

l Linnea G 328: 32% Ginkgo flavonglycosides,8%Terpene lactones

l Linnea G 320: 32% Ginkgo flavonglycosides, without Terpene lactones (mainly used in cosmetic applications)

Origins:

Linnea Ginkgo Biloba Extracts EPG 246, G 328 and G 320 are extracted from the leaves of the Ginkgo Biloba tree dating from the Palaeozoic era (350 million years ago). The Ginkgo Biloba tree, which is notable for high resistance to both pollutants and pests, has a long tradition of use in Oriental medicine; in particular for the treatment and control of respiratory and circulatory ailments and for brain function.

The name Ginkgo is derived from a wrong transcription of the Japanese name Yin-Kwo that means silver fruit, while the name biloba derives from the bilobed shape of its leaf.

Among the pharmacological active constituents those compounds with great importance are the flavonoids (ginkgo flavonol glycosides) and the terpene trilactones (ginkgolides and bilobalide). Different kind of flavonoids has been isolated from the ginkgo extracts. Those of therapeutic interest are glycosyl derivitives of quercitin and kaempferol respectively. Kaempferol is considered particularly relevant for the therapeutic efficacy.

Therapeutic Applications:

Ginkgo biloba extract is believed to have a regulating effect on the entire vascular system of veins, arteries and capillaries. The most common usage of Gingko biloba extract is for its widely accepted effects in the regulation of blood flow to the brain, legs and other extremities. Also commonly cited for the control of the level of various neurotransmitters in the brain thus helping to counteract memory loss, depression and lack of alertness which may occur in old age.

A reported "smart drug" Ginkgo biloba extract may also promote the metabolism of cerebral and neurosensorial cells. Gingko biloba is also used to counteract a number of conditions such as vascular insufficiency and tinnitus and has also been indicated in the treatment of intermittent claudication (pain while walking). Recent studies have also indicated the potential use of Ginkgo biloba in the treatment of Alzheimerﾕs disease. Ginkgo biloba extract is also a free radical scavenger and powerful antioxidant.

Therapeutical Categories:

Vasodilator, Anti-ischemic, Free radical scavenger & Antioxidant

In summary, scientific studies have shown this remarkable natural product to:

l Improve mental functions

l Improve circulation to the brain and extremities as well as in the ear, eye, nose, and throat

l Increase the amount of oxygen and glucose supply to the brain

l Help counter many of the side effects of aging such as short-term memory loss, dizziness, ringing in the ear, depression, intermittent clawdication, and vertigo.

Ginkgo seems to offer protection to the vascular system because of its strong antioxidant properties or free radical scavenging properties. Free radicals are dangerous chemical which can damage the wall of the arteries causing further blockage due to the accumulation of plaque.Ginkgo has no known side effects and has been used in many long term studies. There is no addiction from continued use.

Extracts of Ginkgo are made from dried leaves. Ginkgo contains many different substances, and most of them fall into two categories: Flavonoids and Terpene lactone. Flavonoids are natural substances also found in fruits and vegetables. They act as antioxidants, enhance the immune system and interfere with the formation of tumors. The type in ginkgo is called Ginkgolide. Terpene lactones are the active constituents that give ginkgo a bitter and strong flavor, and helps increase blood circulation.

The active ingredients in ginkgo are believed to have their beneficial effects by thinning the blood, preventing red blood cells and platelet from clotting and, by improving the circulation in the tiny blood vessels such as the capillaries. Studies have shown that they increase the flow of oxygen to the brain, thereby increasing brain cells and working capacity. In some researches conducted in France, it has been shown to have possess beneficial effects in combating a leading cause of age-related hearing loss.

Based on an article in Newletter Medical Herbalist, ginkgo is safe, even when used in large dosage. Like many medical herbs, the ginkgo leaf contains tannins, astringent chemicals, which may cause stomach distress if used in large amount. Today 50:1 extract are tannin-free.