Welcome to Risun Bio-Tech Inc!

Tel:+86-29-8610-0730
Categories
Contact Us

Tel:+86-29-8610-0730

Fax:+86-29-8610-5620

E-mail:sale@risunextract.com

Web:www.risunextract.com

Knowledge

Home > Knowledge > Content
The Description of Wolfberry Extract
Risun Bio-Tech Inc  May 27, 2016

  the description of the wolfberry extract 


   The Chinese name for the lycium plant is gouqi and for the fruits is gouqizi (zi is used to describe small fruits); the common name “wolfberry” comes about because the character gou is related to the one that means dog or wolf.  The spiny shrub has also been called matrimony vine, for reasons long lost.  Carl Linnaeus provided the genus name Lycium in 1753.   He is responsible for the species name barbarum, while botanist Philip Miller described Lycium chinense just 15 years later.   Lycium is extensively cultivated, especially in Ningxia Province, a small autonomous region formerly part of Gansu, with several production projects initiated since 1987.  China now produces over 5 million kilograms of dried lycium fruit each year, most of it for domestic use.  The fruits are dried with or without sulfur to yield the market herb, or the fresh fruits may be squeezed for their juice that is then concentrated to preserve it for future use in making various beverages.


traditional and modern uses 

  Although lycium fruit was described in the Shennong Bencao Jing (ca 100 A.D.), its use in traditional formulas was rather limited until the end of the Ming Dynasty period (1368–1644).   At that time, it was frequently combined with tonic herbs such as rehmannia, cornus, cuscuta, and deer antler to nourish the “kidney” (as described in Chinese medicine) for the treatment of a variety of deficiency syndromes.  This therapeutic approach, using gently warming and “thick” tonifying herbs for nurturing the internal organs, was especially promoted by Zhang Jingyue, whose work is described in the book Jingyue Quanshu(ca 1640).    Lycium fruit is depicted by Chinese doctors as having the properties of nourishing the blood, enriching the yin, tonifying the kidney and liver, and moistening the lungs, but its action of nourishing the yin of the kidney, and thereby enriching the yin of the liver, is the dominant presentation.  It is applied in the treatment of such conditions as consumptive disease accompanied by thirst (includes early-onset diabetes and tuberculosis), dizziness, diminished visual acuity, and chronic cough.  As a folk remedy, lycium fruit is best known as an aid to vision, a longevity aid, and a remedy for diabetes.  With the intensive research work done in recent years, reliance on descriptions of centuries-old use of the herb is less important than for many other Chinese herbs, since much is now known about the chemical constituents and their potential health benefits.


Constituents and Actions

  The color components of lycium fruit are a group of carotenoids, which make up only 0.03–0.5% of the dried fruit (1).  The predominant carotenoid is zeaxanthin (see structure below), which is present mainly as zeaxanthin dipalmitate (also called physalien or physalin), comprising about one-third to one-half of the total carotenoids.  Lycium fruit is considered one of the best food sources of zeaxanthin.

                                                          Zeaxanthin is a yellow pigment (an isomer of lutein and a derivative of β-carotene) produced in plants.  It contributes to the color of corn, oranges, mangoes, and egg yolks (from dietary carotenoids), and it is also the main pigment of another medicinal fruit recently popularized in China: sea buckthorn (hippophae).  When ingested, zeaxanthin accumulates in fatty tissues, but especially in the macula, a region of the retina.  It is believed that by having a good supply of this compound, the macula is protected from degeneration, which can be induced by excessive sun exposure (UV light) and by other “oxidative” processes (2–4).   Lutein, another yellow carotenoid that accumulates in the macula and provides similar protection, is an ingredient of yellow chrysanthemum flowers (juhua) that are often combined with lycium fruits in traditional Chinese herb formulas to benefit the eyes, including deteriorating vision that occurs with aging and may, in some cases, correspond to macular degeneration.  The effective daily dose of these two carotenoids, from food and supplements, has been estimated to be about 10 mg.


  Another plant in the Solanaceae family used in Chinese medicine (though rarely), is Physalis alkekengi, the Chinese lantern plant, which contains zeaxanthin dipalmitate as a major active component.  In addition, the plant contains some steroidal compounds that have been named physalins, producing some confusion about the use of this term because of its former application to the carotenoid.  Physalis is used as a treatment for viral hepatitis, and this effect may be attributed in part to zeaxanthin and also to the steroidal compounds.  Physalis is used for treating a variety of inflammatory disorders, perhaps aiding treatment of infections; extracts of physalis have been shown to increase natural killer cell activity when administered to mice.  


  The red carotenoids of lycium have not been fully analyzed.  It is believed that part is due to lycopene, the major red pigment in tomatoes and capsicum fruits.  The red portion of lycium has been designated as renieratene; the red color overwhelms the yellow of zeaxanthin and the small amount of β-carotene, though the fruits often display an orange tinge due to the yellow components. 


  Benefits of carotenoid intake are thought to mainly arise from prolonged use.  Therefore, lycium fruit, as a source of zeaxanthin and other carotenoids, would be consumed regularly to complement dietary sources, boosting the amount of these components available from fruits and vegetables and egg yolks.


  Another component of lycium is polysaccharides, chains of sugar molecules with high molecular weight (several hundred sugar molecules per chain).  It is estimated that 5-8% of the dried fruits are these polysaccharides , though measures of the active polysaccharides are difficult to undertake, since differentiating functional long chains versus non-functional short chains is challenging; this figure for polysaccharide content is likely on the high side.  Studies of the polysaccharides have indicated that there are four groups of them, each group having slightly different structures and molecular weights .  Although referred to as polysaccharides, the functional immune-regulating substance is actually a polysaccharide-peptide mixture; the amino acid chains maintain a critical structure for the polysaccharide.


  Clinical effects of polysaccharides are also somewhat difficult to determine because absorption after oral administration of polysaccharides is limited and may be quite variable; it is estimated that less than 10% of the high molecular weight plant polysaccharides are absorbed, possibly as little as 1%.  So, most studies of these polysaccharides are done with isolated cells or with injections of the purified component to laboratory animals, yielding results that may or may not occur when these substances are consumed orally.   In one clinical evaluation, cancer patients were treated with a combination of IL-2 and activated lymphokine killer cells plus lycium fruit polysaccharides (which are reported to promote the body’s production of these therapeutic substances), in which patients were given an oral dose of 1.7 mg/kg of the polysaccharides (so, about 100 mg for a 60 kg person), with the reported result that the response rate was higher than without the polysaccharides .  This dose of polysaccharides is quite low compared to usual clinical practice, and further evaluation is needed.


  These lycium fruit polysaccharides, like those obtained from medicinal mushrooms and from several herbs (the best known as a source is astragalus), have several possible benefits, including promoting immune system functions, reducing gastric irritation, and protecting against neurological damage.  The latter application has been the subject of several recent studies at the University of Hong Kong, where lycium polysaccharides are proposed, on the basis of laboratory studies with isolated neurons, to be of benefit to those with Alzheimer’s disease, though clinical trials have not yet been carried out . 


  The immunological impacts of polysaccharides have been the primary focus of study .  One of the primary mechanisms of action for these large molecules may be that they appear to the immune system as though they were cell surface components of microorganisms, promoting activation of a response cascade involving interleukins (such as IL-2) that impact immune cells (such as T-cells).  Since the plant polysaccharides are not the same as the structures on particular pathogens, but have a more poorly defined quality, the response is non-specific.    It is possible that repeated exposure to large amounts of polysaccharides might result in a lessened response, so that this method of therapy is probably best suited to relatively short duration (e.g., a few weeks).  Low dosage exposure may result in no immunological responses, since these polysaccharides are present in several foods in small amounts, and the immune system would be protected from reacting to ordinary exposure levels.


  A review of research on lycium fruit appearing in Recent Advances in Chinese Herbal Drugs , indicates that polysaccharides from lycium fruit enhance both cell-mediated and humoral immune responses.  It was reported, for example, that in laboratory animals, a dose of 5–10 mg/kg lycium fruit polysaccharides daily for one week could increase activity of T-cells, cytotoxic T-cells, and natural killer cells; other studies showed that part of the mechanism of action was via IL-2 stimulation.  The end response to polysaccharide administration did not appear to be solely a stimulation of immune activity, however.  In a laboratory study of lycium on IgE responses, it was noted that lycium fruit reduced antibodies associated with allergy-type reactions, which was presumed to be accomplished through the mechanisms of promoting CD8 T-cells and regulating cytokines; licorice root had a similar effect. 


Extraction and isolation of polysaccharides in low concentration is simple, as they are soluble in hot water that is used as an extracting agent.  Getting a high concentration of polysaccharides is a more significant task.  The easiest method is to first produce a hot water extract of the herb (using more than one extraction to get most of the polysaccharides into solution), and then force the polysaccharides out of solution by adding alcohol, in which they are not soluble; then, the liquid is separated off and the residue is dried to produce the finished polysaccharide product.  This method will also condense other large molecules.  Although small amounts of highly purified polysaccharides can be produced for laboratory and clinical studies, at this time, commercial extracts containing 40% polysaccharides represent the highest concentration available, while 10–15% polysaccharide content from simple hot water extraction is more common.  


  A third constituent of interest is the amino-acid like substance betaine, which is related to the nutrient choline (betaine is an oxidized form of choline and is converted back to choline by the liver when it is ingested).  When added to chicken feed, betaine enhances growth of the animals and increases egg production; it is currently used in poultry farming because of these effects.  In recent years, betaine has been included in some Western nutritional supplement products, especially those used for improving muscle mass, using several hundred milligrams for a daily dose.  Betaine was shown to protect the livers of laboratory animals from the impact of toxic chemicals; other pharmacologic studies have shown that it is an anticonvulsant, sedative, and vasodilator.   It has been suggested that betaine could aid the treatment of various chronic liver diseases, such as non-alcoholic fatty liver disease.  Betaine is found also in capsicum, silybum (the source of the liver-protective flavonoid silymarin), and beets (Beta vulgaris, from which betaine gets its name).  The amount of betaine in lycium fruit, is about 1% , so to get a significant amount, a large dose of lycium fruit would need to be consumed (e.g., 20–30 grams).


  The mild fragrance of the fruits is attributed to a small amount of volatile oils, mainly two sesquiterpenes: cyperone and solavetivone .  The amount present does not have significant pharmacological functions when lycium is consumed in ordinary amounts. The fruit also contains about 0.15% flavonoids, including rutin and chlorogenic acid .