Hypericum perforatum parts

Flavonoids in the diet have been widely promoted as important antioxidant contributors. Their neuroprotective properties, because of this effect, have been demonstrated by several workers. However, they have also been demonstrated to have MAOI activity and this has been proposed as part of the explanation of the use of the common herb, St Johns Wort, Hypericum perforatum L., as an antidepressant. This dual role has now been proposed for a variety of flavonoids, such as kaempferol (22) from the leaves of Ginkgo biloba L., a widely used herbal product which has been suggested as a preventative agent against neurodegeneration. Quercetin (23), similarly, has also shown to inhibit MAO-B " and reverse the effects of induced catalepsy, which mimics the bradykinesia associated with PD. Tangeretin (24) also inhibits MAO-B and crosses the blood brain barrier in a rat model. 

St. John s wort is derived from the flowers of the Hypericum perforatum plant that grows throughout England, Europe, Asia, and parts of the United States. This herbal supplement has been used extensively to treat symptoms of depression and anxiety. Although the details are unclear, St. John s wort probably contains several chemicals that alter the balance of central nervous system (CNS) neurotransmitters affecting mood and behavior.46,84 As discussed in Chapter 7, depression seems to be associated with a fundamental defect in amine neurotransmitters such as serotonin, norepinephrine, and dopamine. St. John s wort may promote changes in these neurotransmitters in a manner similar to conventional prescription antidepressants.56,84 Many people have therefore used St. John s wort as an alternative medication to help improve mood and resolve the symptoms of depression.46,72... 

The commercial products of St. John s wort are derived from the dried flowering tops or aerial parts of Hypericum perforatum L. they are harvested shortly before or during the flowering period. Hypericum preparations include the dried herb (chopped or powdered), tea infusion, liquid extract, dried (hydroalcoholic) extract, oil, and tincture. 

The herb St. John s wort (Hypericum perforatum) has a number of constituent parts, including hyperforin, which is currently being studied as the responsible constituent for the antidepressant action. The herb contains at least ten compounds that can have an unpredictable effect on the consumer. 

ST. JOHN S WORT, Hyperici herba, is the dried aerial parts of Hypericum perforatum... 

A second major herbal medicine is St. John s wort, which consists of the leaves and flowering parts of Hypericum perforatum L. (Clusiaceae). It is sold as an antidepressant in both the United States and Europe and its sales in... 

Several investigations have studied the in vivo antidepressant activity of this herb and of compounds isolated from it. For example, a commercially available extract of the aerial parts of Hypericum perforatum LI 160 and hypericin, Fig. (13) showed pronounced activity in selected animal bioassays. These include the forced swimming test and the tail suspension test, used to determine antidepressant activity, and tests indicating activity on the central nervous system, such as body temperature and ketamine-induced sleeping time [231,232],... 

For a hydroalcoholic extract of Hypericum perforatum, produced by successive extraction of dried aerial parts with petroleum ether, 1,2-dichlorethane and ethanol (50 % v/v), a sedative effect in mice has been reported [123]. The authors observed a bell-shaped dose-response effect on spontaneous motility with maximal activity at an oral dose of 26.5 mg/kg p.o, while pentobarbital-induced sleeping time was most significantly prolonged at the lowest dose applied (13.25 mg/kg p.o.). No effect on neuromuscular transmission was observed in three different test models (chimney test, traction test and rota-rod test). After separation of the crude extract in fractions containing mainly flavones, naphthodianthrones or amino acids, it was not possible to clearly attribute the effect of the native extract to a particular group of constituents. Thus, the authors conclude that activity of the hydroalcoholic extract may results form the cumulative effects of different compound, but they do not offer any explanation for the lower activity of the extract at higher doses. 

While this book by necessity deals, in the main, with the properties of isolated plant constituents, the reader is reminded of the phenomenon of synergy—where the interaction of two or more agents results in a combined effect that is greater than the sum of the individual parts (i.e. of the additive effects). This process is often referred to in herbal medicine circles (e.g. for Hypericum perforatum) although it is a difficult one to prove. The primary application of this concept is in the traditional methods of combining herbal medicines in formulas however, in recent times it has also been applied using the combined effects of active constituents within the same herb. 

In 2012, different pectin fractions were extracted from the above-ground part of St. John s wort Hypericum perforatum L) [110]. Using an aqueous solution of ammonium oxalate, the results obtained indicate that pectins have a low degree of esterification with 4.8% for the fraction with higher nelds, and a total of 6.2%. With the results obtained, the above-ground part of St John s wort can be considered a source of LDE pectin extraction, and relatively low yields can be improved using other extraction methods. 

Hypericin 1 is present in plants, insects and protozoa. In plants, apart from H. perforatum, it occurs in a number of other species of Hypericum, namely H. hirsutum, H. maculatum, H. nummularium and H. triquetrifolium [17]. It is located in minute glands on different parts of the plants such as young stems, leaves and flowers. Interestingly, hypericin 1 is found in the integument of Australian Lac insects of the Coccoidea family, and appears with a number of structurally-related compounds [18, 19]. In protozoa, the blue-green ciliate, Stentor coerulus possesses a photoreceptor, stentorin, which consists of proteins bound to hypericin 1 [20]. 

H.perforatum, 13, II8-biapigenin 46 as the major, and 13 , II8-biapigenin (= amentoflavone) 47 as minor components [87, 88]. There were some assumptions that biflavones could contribute to the antidepressant activity of St. John s Wort, however their significance remains unclear [7]. Of the xanthones, a very typical class of compounds in the Guttiferae family, only two have been reported to occur in H. perforatum [89, 90]. The xanthonolignoid kielcorin 48 was isolated and identified by Nielsen and Arends from root materials of this and several other Hypericum species [91]. In aerial parts of H. perforatum, a trace amount of 1,3,6,7-tetrahydroxyxanthone 49 was found by Berghofer [86]. 

Traditional use In folk medicine Hypericum scabrum is used in a similar manner as H. perforatum (Khalmatov 1964). The aboveground parts are collected during flowering before the appearance of unripe fruits and are used to treat coughs and liver, heart, stomach, intestinal, and bladder diseases. An infusion of the flowers is used to treat jaundice (Khodzhimatov... 

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