Archive for category Ginkgo biloba'

Industrial Quality Control of Ginkgo Products

The marketing of pharmaceutical products in Europe requires an authorisation, according to the directives 65/65 EEC and 75/318 EEC. Phytomedicines are included in this general legislation, and are subjected to the same treatment as medicinal products in general. Thus, evidence of the product’s safety, efficacy and quality has to be submitted before a marketing authorisation will be granted. In this chapter the focus will be on the parameters and the analytical methods to evaluate the quality of Ginkgo biloba leaves extracts and finished products. Earlier experience gained at the University of Lausanne (Camponovo) and at Pharmaton for the standardisation of GK 501 Ginkgo biloba extract Pharmaton and for the finished product Gincosan and Memfit Pharmaton, plays an important role in this. Control of Starting Material (Ginkgo Biloba Leaves) A consistent quality for products of vegetable origin can only be guaranteed if the starting materials are rigorously defined. But what does a good quality of Ginkgo leaves mean? So far, there are no pharmacopoeia monographs on Ginkgo biloba leaf to which one can refer. Each producer supplies its own monograph with some specifications that are more or less detailed and dependent Read more […]

Development of the U.S. Pharmacopeia’s Monograph on Ginkgo Biloba

It is amazing that the Ginkgo tree, Ginkgo biloba L., the last remaining member of the Ginkgoaceae family has suddenly engaged the interest of Western medicine. Worldwide use of Ginkgo leaf extracts is reported to be on the rise in view of the reported beneficial effects of the Ginkgo as an antiasthmatic and on the circulatory system. Is it more appropriate to say that Western medicine has at last considered the medicinal properties of Ginkgo biloba whose fruits and seeds have been valued in China for their medicinal properties for the last several hundred years? Though the leaves of Ginkgo biloba were sparsely used, in comparison to the fruits and seeds, in ancient medicines in the East, the Western medicine as practiced extensively in Europe uses the leaves. Senna leaves are used directly in the preparation of tea, but traditionally extracts of Ginkgo leaves are used directly in the Western medicine preparations. United States Pharmacopeia’s (USP) interest and involvement in the development and establishment of public standards began in 1820 with the publication of its first edition. The first edition of the United States Pharmacopeia included monographs on botanicals. Thereafter for the next 120 years or so the Read more […]

Development of the U.S. Pharmacopeia’s Monograph on Ginkgo Biloba: Appendix

Ginkgo Leaf Ginkgo leaf consists of the dried leaf of Ginkgo biloba Linn (Fam. Ginkgoaceae. Packaging and storage Preserve in well-closed containers, protected from light and moisture. Labeling The label states that it is Ginkgo Leaf and states also the genus and species. USP Reference standards USP Quercetin RS, USP Rutin RS. Botanic characteristics Macroscopic: Dried whole, folded or fragmented leaves, with or without attached petiole, varying from khaki green to greenish-brown in color, often more brown at the apical edge, and darker on the adaxial surface. Lamina broadly obcuneate (fan shaped), 2 to 12cm in width and 2 to 9.5cm in length from petiole to apical margin; mostly 1.5 to 2 times wider than long. Base margins entire, concave; apical margin sinuate, usually truncate or centrally cleft, and rarely multiple cleft. Surface glabrous, with wrinkled appearance due to prominent dichotomous venation appearing parallel and extending from the lamina base to the apical margin. Petiole of a similar color to leaf, channeled on the adaxial surface, 2 to 8cm in length. Histology — Transverse section of lamina: A thin but marked cuticle occurs over a single layer of epidermal cells on both surfaces. Read more […]

Alkyl Phenols in Ginkgo Biloba

The phenolic lipids are a comparatively little known group of compounds which may be considered as biogenetically derived from fatty acids and containing a benzene ring, one to two phenolic groups and zero to one carboxyl group on the benzene ring. Some of them have had an applied artistic use for centuries for the preparation of Japanese and Chinese lacs, and others, e.g. the Cashew Nut Shell Liquid (CNSL) play a vital role in certain modern technical uses for chemical treatments and industrial utilizations. Historically, most of the analytical work on alkyl phenols has been carried out on Anacardium occidentale, because of its commercial value, and the acquired experience was translated to other alkyl phenols containing plants. This paper reviews the literature concerning the characterization of these compounds in Ginkgo biloba plant materials and in pharmaceutical preparations mainly derived from the leaves of the plant. In fact, side effects concerning the allergenic properties of this class of compounds, have been described, and a number of industrial processes have been set up in order to avoid their occurrence in phytopharmaceuticals. A small review on the chemistry and biology of ginkgo alkylphenols has appeared Read more […]

Flavonoids of Ginkgo Biloba

The use of Ginkgo preparations for the treatment of cough, bronchial asthma, irritable bladder and alcohol abuse can be traced back to the origins of Chinese herbal medicine. But the modern use of Ginkgo phytomedicines is not derived from traditional medicine. Research on Ginkgo biloba, done by the pharmaceutical company of Dr. W.Schwabe, Karlsruhe, Germany, led to the introduction of Ginkgo leaf extracts in 1965 for the treatment of circulatory diseases resulting from older age. Today, preparations containing Ginkgo leaf extracts are among the best selling phytopharmaceuticals in Europe, particularly in France and Germany. Compared to the importance of Ginkgo preparations, there is only a very small number of publications dealing with quality control of Ginkgo and Ginkgo preparations. To date, only a few general quality standards for Ginkgo leaves and Ginkgo phytomedicines have been published, although various laboratories are actively involved in the analysis of Ginkgo constituents. It appears that the marketing strategies of most companies which produce Ginkgo preparations do not permit the publication of the company-developed quality control standards. A monograph entitled “Ginkgo folium” is in preparation for the Read more […]

Ginkgo (Ginkgo Biloba)

Medical Uses Ginkgo is used for circulation problems, Alzheimer’s disease, difficulties with memory, ringing in the ears, headaches, and dizziness. Ginkgo biloba is licensed in Germany for treating: cerebral dysfunction with difficulties in memory, dizziness, tinnitus (ringing in the ears), headaches, emotional instability with anxiety, and intermittent claudication. Historical Uses Legend has it that Chinese monks saved the ginkgo tree from extinction by growing it in monastery gardens. Growth The ginkgo is the oldest known living tree in the world. It is not difficult to grow, and ginkgo trees can be found in many city areas in the United States, including Central Park in New York City. The trees are able to withstand pollution and disease. Their leaves turn yellow in the fall. Ginkgo: Part Used • Dried leaves Major Chemical Compounds • Diterpenes known as ginkgolides, sesquiterpene bilobalide, quercetin Ginkgo: Clinical Uses Ginkgo is used for peripheral vascular disease, such as intermittent claudication and cerebral insufficiency. It is approved by the German Commission E and the World Health Organization. Ginkgo biloba is licensed in Germany for treating cerebral dysfunction with difficulties Read more […]

Herb-Drug Interactions: Ginkgo

Ginkgo biloba L. (Ginkgoaceae) Synonym(s) and related species Fossil tree, Kew tree, Maidenhair tree. Salisburia adiantifolia Sm., Salisburia biloba Hoffmanns. Pharmacopoeias Ginkgo (US Ph 32); Ginkgo capsules (US Ph 32); Ginkgo dry extract, refined and quantified (British Ph 2009, European Ph 2008); Ginkgo leaf (British Ph 2009, European Ph, 6th ed., 2008 and Supplements 6.1, 6.2, 6.3 and 6.4); Ginkgo tablets (US Ph 32); Powdered ginkgo extract (The United States Ph 32). Constituents Ginkgo leaves contain numerous flavonoids including the biflavone glycosides such as ginkgetin, isoginkgetin, bilobetin, sciadopitysin, and also some quercetin and kaempferol derivatives. Terpene lactones are the other major component, and these include ginkgolides A, B and C, and bilobalide, Ginkgo extracts may be standardised to contain between 22 and 27% flavonoids (flavone glycosides) and between 5 and 12% terpene lactones, both on the dried basis. The leaves contain only minor amounts of ginkgolic acids, and some pharmacopoeias specify a limit for these. The seeds contain ginkgotoxin (4-O-methylpyridoxine) and ginkgolic acids. Use and indications The leaves of ginkgo are the part usually used. Ginkgo is often used Read more […]

Ginkgo biloba: Contraindications. Practice Points. FAQ

Contraindications and Precautions If unusual bleeding or bruising occurs, stop use immediately. Although new clinical evidence suggests that Ginkgo biloba does not affect clotting times, it may be prudent to suspend use for 1 week prior to major surgery. CEREBRAL HAEMORRHAGE AND EPILEPSY Recent, rare case reports have suggested that ginkgo should be used with caution in people with known risk factors for cerebral haemorrhage and epilepsy until further investigation can clarify its safety. Pregnancy Use Not recommended in pregnancy as insufficient reliable evidence is available to determine safety. Practice Points / Patient Counselling • Ginkgo biloba is a complex herb that contains many different active constituents and works by means of multiple mechanisms. Therefore, it has applications in many varied conditions. • It is an effective treatment in conditions of acquired cognitive impairment, including dementia of any degree of severity and intermittent claudication, according to evidence from meta-analyses. • Positive evidence also exists for premenstrual syndrome, sudden deafness, Raynaud’s syndrome and depression when associated with cognitive decline. • Largely based on the herb’s physiological Read more […]

Ginkgo biloba: Significant Interactions

PLATELET INHIBITOR DRUGS Due to its platelet-activating factor antagonist activity, Ginkgo biloba may theoretically enhance the effects of these drugs and increase risk of bruising or bleeding; however, three clinical trials have cast doubt on the clinical significance of this activity — observe patients taking this combination. WARFARIN Theoretically, ginkgo may increase bleeding risk when used together with warfarin; however, two randomised double-blind studies have found that Ginkgo biloba does not affect the pharmacokinetics, pharmacodynamics, INR or clinical effects of warfarin, and two clinical trials have not found evidence of significant effects on bleeding. Due to the potential seriousness of such an interaction, caution is still advised. CHOUNERGIC DRUGS Cholinergic activity has been identified for ginkgo; therefore, combined use may theoretically increase drug activity — observe patients using this combination, although the effects may be beneficial when used under supervision. DOXORUBICIN In vivo research suggests that ginkgo can prevent doxorubicin-induced cardiotoxicity suggesting a potentially beneficial interaction, although no human studies are available to confirm clinical significance. ANTIDEPRESSANT Read more […]

Ginkgo biloba: Uses. Dosage. Adverse Reactions

Other Uses Ginkgo biloba is used for many other indications, including improving connective tissue conditions such as haemorrhoids, common allergies, reducing the effects of exposure to radiation and to prevent some of the complications associated with diabetes. In the UK and other European countries, the cardioprotective effects of EGb 751 in myocardial ischaemia and reperfusion are currently being investigated in preclinical studies. ADJUNCT IN CANCER TREATMENT As a herb with significant antioxidant activity, ginkgo has been used to reduce the toxic side-effects of some chemotherapeutic drugs. Evidence from in vivo studies demonstrate protective effects against nephrotoxicity induced by cisplatin and cardiotoxicity induced by doxorubicin. Clinical trials are not yet available to determine its effectiveness in practice. CANCER PREVENTION A 2005 review puts forward the case that Ginkgo biloba should be more widely used as a safe, preventative agent for reducing cancer incidence. This recommendation is based on results from numerous in vitro and experimental studies showing that ginkgo affects many factors associated with the incidence and mortality of cancer. Dosage Range The recommended dose varies depending Read more […]