Lycium

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Wolfberry, commercially called goji berry, is the common name for the fruit of two very closely related species: Lycium barbarum (Chinese: 寧夏枸杞; pinyin: Níngxià gǒuqǐ) and L. chinense (Chinese: 枸杞; pinyin: gǒuqǐ), two species of boxthorn in the family Solanaceae (which also includes the potato, tomato, eggplant, deadly nightshade, chili pepper, and tobacco). It is native to southeastern Europe and Asia.^[1]

It is also known as Chinese wolfberry, mede berry, barbary matrimony vine, bocksdorn, Duke of Argyll's tea tree, Murali (in India),^[2] red medlar, or matrimony vine.^[3]

Description

This section does not cite any references or sources. (May 2009)

Lycium barbarum illustration from Flora von Deutschland, Österreich und der Schweiz, by Prof. Dr. Otto Wilhelm Thomé, 1885, Gera, Germany.

Wolfberry species are deciduous woody perennial plants, growing 1–3 m high. L. chinense is grown in the south of China and tends to be somewhat shorter, while L. barbarum is grown in the north, primarily in the Ningxia Hui Autonomous Region, and tends to be somewhat taller.

Leaves and flower

Wolfberry leaves and flower

Wolfberry leaves form on the shoot either in an alternating arrangement or in bundles of up to three, each having a shape that is either lanceolate (shaped like a spearhead longer than it is wide) or ovate (egg-like). Leaf dimensions are 7-cm wide by 3.5-cm broad with blunted or round tips.

The flowers grow in groups of one to three in the leaf axils. The calyx (eventually ruptured by the growing berry) consists of bell-shaped or tubular sepals forming short, triangular lobes. The corolla are lavender or light purple, 9–14 mm wide with five or six lobes shorter than the tube. The stamens are structured with filaments longer than the anthers. The anthers are longitudinally dehiscent.

In the northern hemisphere, flowering occurs from June through September and berry maturation from August to October, depending on the latitude, altitude, and climate.

Fruit

These species produce a bright orange-red, ellipsoid berry 1–2-cm deep. The number of seeds in each berry varies widely based on cultivar and fruit size, containing anywhere between 10–60 tiny yellow seeds that are compressed with a curved embryo. The berries ripen from July to October in the northern hemisphere.

Etymology

Lycium, the genus name, is derived from the ancient southern Anatolian region of Lycia (Λυκία).^[4] The fruit is known in pharmacological references as Lycii fructus, which is Latin for "Lycium fruit".

"Wolfberry" is the most commonly used English common name^{[citation needed]}. The origin of this name is unknown, perhaps resulting from confusion over the genus name Lycium, which resembles "lycos", the Greek word for wolf.

In the English-speaking world, the name "goji berry" has been used since the early 21st century.^{[citation needed]} The word "goji" is an approximation of the pronunciation of gǒuqǐ (枸杞), the name for the berry producing plant in several Chinese dialects, including Hokkien and Shanghainese. This name possibly derives from the same roots as the Persian language term gojeh (گوجه) which means "plum/berry".

Other common names are "the Duke of Argyll's Tea Tree"^[3] and "matrimony vine".^[3]

In Tibetan the plant is called dretsherma (), with dre meaning "ghost" and tsherma meaning "thorn".^{[citation needed]}

Significance

Since the early 21st century there has been rapidly growing attention for wolfberries for their nutrient value and antioxidant content. They have been termed a superfruit, which has led to a profusion of consumer products.^[5][6]

Cultivation

China

The majority of commercially produced wolfberries come from the Ningxia Hui Autonomous Region of north-central China and the Xinjiang Uyghur Autonomous Region of western China, where they are grown on plantations. In Zhongning County, Ningxia, wolfberry plantations typically range between 40 and 400 hectares (100–1000 acres or 500–6000 mu) in area. As of 2005, over 10 million mu have been planted with wolfberries in Ningxia.^[7]

Cultivated along the fertile aggradational floodplains of the Yellow River for more than 600 years, Ningxia wolfberries have earned a reputation throughout Asia for premium quality sometimes described commercially as "red diamonds".^[8] Government releases of annual wolfberry production, premium fruit grades, and export are based on yields from Ningxia, the region recognized with

• The largest annual harvest in China, accounting for 42% (13 million kilograms, 2001) of the nation's total yield of wolfberries, estimated at approximately 33 million kilograms (72 million pounds) in 2001.
• Formation of an industrial association of growers, processors, marketers, and scholars of wolfberry cultivation to promote the berry's commercial and export potential.
• The nation's only source of therapeutic grade ("superior-grade") wolfberries used by practitioners of traditional Chinese medicine.^[9]

In addition, commercial volumes of wolfberries grow in the Chinese regions of Inner Mongolia, Qinghai, Gansu, Shaanxi, Shanxi, and Hebei. When ripe, the oblong, red berries are tender and must be picked carefully or shaken from the vine into trays to avoid spoiling. The fruits are preserved by drying them in full sun on open trays or by mechanical dehydration employing a progressively increasing series of heat exposure over 48 hours.

Wolfberries are celebrated each August in Ningxia with an annual festival coinciding with the berry harvest.^[7] Originally held in Ningxia's capital, Yinchuan, the festival has been based since 2000 in Zhongning County, an important center of wolfberry cultivation for the region.^[7] As Ningxia's borders merge with three deserts, wolfberries are also planted to control erosion and reclaim irrigable soils from desertification.^[10]

China, the main supplier of wolfberry products in the world, had total exports generating US$120 million in 2004. This production derived from 82,000 hectares farmed nationwide, yielding 95,000 tons of wolfberries.^[8]

Pesticide and fungicide use

Organochlorine pesticides are conventionally used in commercial wolfberry cultivation to mitigate destruction of the delicate berries by insects. Since the early 21st century, high levels of insecticide residues (including fenvalerate, cypermethrin, and acetamiprid) and fungicide residues (such as triadimenol and isoprothiolane), have been detected by the United States Food and Drug Administration in some imported wolfberries and wolfberry products of Chinese origin, leading to the seizure of these products.^[11]

China's Green Food Standard, administered by the Chinese Ministry of Agriculture's China Green Food Development Center, does permit some amount of pesticide and herbicide use.^[12][13][14] Agriculture in the Tibetan plateau (where many "Himalayan" or "Tibetan"-branded berries originate) conventionally uses fertilizers and pesticides, making organic claims for berries originating here dubious.^[15]

United Kingdom

The Duke of Argyll introduced Lycium barbarum into the United Kingdom in the 1730s where it is known as Duke of Argyll's Tea Tree.^[3] It was and still is used for hedging, especially in coastal districts. Its red berries are attractive to a wide variety of British birds.^[16]

The plant continues to grow wild in UK hedgerows. On 15 January 2003, the Department for Environment, Food and Rural Affairs launched a project to improve the regulations protecting traditional countryside hedgerows, and specifically mentioned Duke of Argyll's Tea Tree as one of the species to be found growing in hedges located in Suffolk Sandlings, Hadleigh, Bawdsey, near Ipswich, and Walberswick.^[17]

On June 18, 2007, the FSA (UK Food Standards Agency) stated that there was a significant history of the fruit being consumed in Europe before 1997, and has removed it from the Novel Foods list.^[18] It is now legal to sell the wolfberry in the UK as a food as reported by the British Food Standards Agency,^[19] but see section below: Marketing claims under scrutiny in Europe.

Importation of mature plants

Importation of wolfberry plants into the United Kingdom from most countries outside Europe is illegal, due to the possibility they could be vectors of diseases attacking Solanaceae crops, such as potato or tomato.^[20]

Uses

Dried wolfberries

Wolfberries are usually sold in open boxes and small packages in dried form.

Formerly frozen goji berries

Culinary

As a food, dried wolfberries are traditionally cooked before consumption. Dried wolfberries are often added to rice congee and almond jelly, as well as used in Chinese tonic soups, in combination with chicken or pork, vegetables, and other herbs such as wild yam, Astragalus membranaceus, Codonopsis pilosula, and licorice root. The berries are also boiled as an herbal tea, often along with chrysanthemum flowers and/or red jujubes, or with tea, particularly pu-erh tea,^{[citation needed]} and packaged teas are also available.

Various wines containing wolfberries (called gǒuqǐ jiǔ; 枸杞酒) are also produced,^[21][22] including some that are a blend of grape wine and wolfberries.

At least one Chinese company^{[citation needed]} also produces wolfberry beer, and New Belgium Brewery makes their seasonal Springboard ale with wolfberries used as flavoring. Since the early 21st century, an instant coffee product containing wolfberry extract has been produced in China.^{[citation needed]}

Young wolfberry shoots and leaves are also grown commercially as a leaf vegetable.^{[citation needed]}

Preliminary medical research

Marketing literature for wolfberry products including several "goji juices" suggest that wolfberry polysaccharides have biological effects and possible health benefits, although no such claims have been supported by peer-reviewed research or approved by any regulatory agency.

A 2008 pilot study^[23] indicated that parametric data did not show significant differences between subjects receiving Lycium barbarum berry juice and subjects receiving a placebo; the authors, nevertheless, concluded that subjective measures had been affected. This study was subject to various criticisms concerning its experimental design and interpretations.^[24]

Published studies have also reported biological effects of Lycium barbarum in animal models,^[25] and speculated from this basic research that there may be potential benefits against cardiovascular and inflammatory diseases,^[26][27] vision-related diseases^[28] (such as age-related macular degeneration and glaucoma^[29]) or from neuroprotective,^[30] anticancer^[31] or immunomodulatory activity.^[32]

In Traditional Chinese Medicine, Lycium leaves may be used in a tea, together with the root bark (called dìgǔpí; 地 骨 皮). A glucopyranoside (namely (+)-Lyoniresinol-3α-O-β-d-glucopyranoside) and phenolic amides (dihydro-N-caffeoyltyramine, trans-N-feruloyloctopamine, trans-N-caffeoyltyramine and cis-N-caffeoyltyramine) isolated from wolfberry root bark have inhibitory activity in vitro against human pathogenic bacteria and fungi.^[33][34]

Safety issues

Two published case reports described elderly women who experienced increased bleeding, expressed as an elevated INR, after drinking quantities of wolfberry tea.^[35][36] Further in vitro testing revealed that the tea inhibited warfarin metabolism, providing evidence for possible interaction between warfarin and undefined wolfberry phytochemicals.^[35]

Atropine, a toxic alkaloid found in other members of the Solanaceae family, occurs naturally in wolfberry fruit. The atropine concentrations of berries from China and Thailand was tested and found to be variable, with a maximum content of 19 ppb, well below a toxic level.^[37] However, misidentified or adulterated samples with higher atropine levels may explain earlier, much higher, measurements.^[37]

Nutrient content

This section needs additional citations for verification. (April 2011)

Micronutrients and phytochemicals

Wolfberries contain many nutrients and phytochemicals including

• 11 essential and 22 trace dietary minerals
• 18 amino acids
• 6 essential vitamins
• 8 polysaccharides and 6 monosaccharides
• 5 unsaturated fatty acids, including the essential fatty acids, linoleic acid and alpha-linolenic acid
• beta-sitosterol and other phytosterols
• 5 carotenoids, including beta-carotene and zeaxanthin (below), lutein, lycopene and cryptoxanthin, a xanthophyll
• numerous phenolic pigments (phenols) associated with antioxidant properties

Select examples given below are for 100 grams of dried berries.

• Calcium. Wolfberries contain 112 mg per 100 gram serving, providing about 8–10% of the Dietary Reference Intake (DRI).
• Potassium. Wolfberries contain 1,132 mg per 100 grams dried fruit, giving about 24% of the DRI.
• Iron. Wolfberries have 9 mg iron per 100 grams (100% DRI).
• Zinc. 2 mg per 100 grams dried fruit (18% DRI).
• Selenium. 100 grams of dried wolfberries contain 50 micrograms (91% DRI)
• Riboflavin (vitamin B₂). At 1.3 mg, 100 grams of dried wolfberries provide 100% of DRI.
• Vitamin C. Vitamin C content in dried wolfberries has a wide range (from different sources^{[citation needed]}) from 29 mg per 100 grams to as high as 148 mg per 100 grams (respectively, 32% and 163% DRI).

Wolfberries also contain numerous phytochemicals for which there are no established DRI values. Examples:

• Beta-carotene: 7 mg per 100 grams dried fruit.
• Zeaxanthin. Reported values for zeaxanthin content in dried wolfberries vary considerably, from 2.4 mg per 100 grams^[38] to 82.4 mg per 100 grams^[39] to 200 mg per 100 grams.^[40] The higher values would make wolfberry one of the richest edible plant sources known for zeaxanthin content.^[41] Up to 77% of total carotenoids present in wolfberry exist as zeaxanthin.^[42]
• Polysaccharides. Polysaccharides are a major constituent of wolfberries, representing up to 31% of pulp weight.

Wolfberry polysaccharides

One study^[43] published in the Journal of Ethnopharmacology found that:

Endogenous lipid peroxidation, and decreased antioxidant activities, as assessed by superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and total antioxidant capacity (TAOC), and immune function were observed in aged mice and restored to normal levels in Lycium polysaccharide-treated groups. Antioxidant activities of Lycium barbarum polysaccharides were found to be comparable with normal antioxidant, vitamin C. Furthemore, adding vitamin C to the polysaccharide treatment further increased in vivo antioxidant activity of the polysaccharides.^[43]

Criticism

Marketers^[which?] of some wolfberry products claim that polysaccharides have specific physiological roles mediated by specialized cell receptors "master" control properties over other bioactive chemicals and cells.^{[citation needed]} Characteristic spectral peaks are claimed to define one berry's geographic origin from another.^[44]

These assertions are an important marketing message for wolfberry products branded as Tibetan Goji Berries or Himalayan Goji Juice. Such statements, however, have no scientific evidence published under peer-review^{[citation needed]} and are not compliant with regulatory guidelines for marketing natural food products (see below, Marketing claims under scrutiny in Europe, Canada and the United States).

Functional food and beverage applications

It is often cultivated for a variety of food and beverage applications within China, but increasingly today for export as dried berries, juice, and pulp or grounds. Wolfberries are prized for their versatility of color and nut-like taste^{[citation needed]} in common meals, snacks, beverages, and medicinal applications. A major effort is underway in Ningxia, China to process wolfberries for “functional” wine.

Marketing

Since the early 21st century, the dried fruit has been marketed in the West as a health food (typically under the name "Tibetan goji berry"^{[citation needed]}), often accompanied by scientifically unsupported claims regarding its purported health benefits.

Its most claimed nutritional attribute^{[citation needed]} is an exceptional level of vitamin C, to be among the highest in natural plants.^{[citation needed]} However, it was demonstrated by independent assays on dried berries to be quite variable, in a range of 29–148 mg per 100 grams of fruit^{[citation needed]}. This level is comparable to many citrus fruits and strawberries^[45] as well as numerous other fruits and berries.

Companies marketing the berries often also include the unsupported myth that a Chinese man named Li Qing Yuen, who was said to have consumed wolfberries daily, lived to the age of 252 years (1678–1930).

Commercial products marketed outside Asia

Typical of many exotic fruits being introduced into western food and beverage commerce, wolfberry is best known as a juice marketed over the Internet since 2002, often via multi-level marketing that asserts its health benefits^{[citation needed]}. There is an increasing presence of wolfberry in health food stores and grocery markets in many countries^{[citation needed]}.

While juice prepared entirely from fresh wolfberries is rare,^{[citation needed]} blends containing several other berry and fruit juices are used for nearly all "wolfberry" juice products, many of which are nevertheless labeled as "goji juice"^{[citation needed]}. The percentage of wolfberry contained in these juices is generally not stated on the labels of such products.^{[citation needed]}

Other wolfberry consumer applications are

• Dried berries (pictured above)
• Berry pieces in granola bars^{[citation needed]} and
• Skin soap^{[citation needed]} (made from seed oils)
• Yogurt products

Commercial suppliers have processed wolfberry as

• An additive for manufacturing
• Juice concentrate
• Whole fruit purée
• Powders from juice or juice concentrate made from spray drying^{[citation needed]}
• Pulp powders
• Whole or ground seeds
• Seed oils (as with grape seed oil), and essential oils derived from seeds)^{[citation needed]}.

Marketing claims under scrutiny in Europe

In February 2007, the Food Standards Agency (FSA) of the United Kingdom, an advisor for food safety to the European Food Safety Authority of the European Union (EU), published an inquiry to retailers and health food stores requesting evidence of significant use of wolfberries in Europe before 1997.^[46] This period would document a safety history and evaluate how "novel" the berries are in the EU, affecting their authorization status for sale.

Proponents hoped this review would provide important safeguards for consumers by checking whether new foods are suitable for the whole population, including people with food allergies. Opponents on the other hand feared it would limit consumer choice and protect monopolistic interests rather than the public.^[47] Food safety in the EU relies importantly on a scientific basis for label information on foods like wolfberries that may be claimed to furnish health benefits.^[48]

In June 2007, the FSA announced its decision that wolfberries indeed had a history of use in Great Britain before 1997.^[49][50] Accordingly, wolfberries do not require registration as a novel food.

Marketing claims under scrutiny in Canada and the United States

In January 2007, marketing statements for a goji juice product were subject of an investigative report by CBC Television's consumer advocacy program Marketplace.^[51]

By one specific example in the CBC interview, Earl Mindell (then working for direct-marketing company FreeLife International, Inc.) claimed the Memorial Sloan-Kettering Cancer Center in New York had completed clinical studies showing that use of wolfberry juice would prevent 75% of human breast cancer cases, a false statement. There are preliminary laboratory studies^[31][52][53] and one Chinese clinical trial.^[54]

During 2006, the U.S. Food and Drug Administration (FDA) placed two goji juice distributors on notice with warning letters about marketing claims.^[55][56] These statements were in violation of the United States Food, Drug and Cosmetic Act [21 USC/321 (g)(1)]^[57] because they "establish the product as a drug intended for use in the cure, mitigation, treatment, or prevention of disease" when wolfberries or juice have had no such scientific evaluation. Additionally stated by the FDA, the goji juice was "not generally recognized as safe and effective for the referenced conditions" and therefore must be treated as a "new drug" under Section 21(p) of the Act. New drugs may not be legally marketed in the United States without prior approval of the FDA.

On May 29, 2009, a class action lawsuit was filed against FreeLife in the United States District Court of Arizona. This lawsuit alleges false claims, misrepresentations, false and deceptive advertising and other issues regarding FreeLife’s Himalayan Goji Juice, GoChi, and TaiSlim products. This lawsuit seeks remedies for consumers who have purchased these products over the past several years.^[58][59]

See also

• Gouqi jiu
• List of culinary fruits
• Sea buckthorn – another medicinal plant that somewhat resembles Wolfberry

References

Further reading

Books

• Ai, Changshan (2002). Zhi Bu Liang Yi Hua Gou Qi (A Word About Lycium chinense, Effective for Therapy and Nutrition). Changchun, China: Jilin Ke Xue Ji Shu Chu Ban She. ISBN 7-5384-2402-4. ISBN 978-7-5384-2402-7.
• Gross, P.M./Zhang, R./Zhang, X. (2006). Wolfberry: Nature's Bounty of Nutrition and Health. BookSurge Publishing. ISBN 978-1-4196-2048-5
• Oyama, Sumita (1964). Kuko o Aishite Junen (Lycium chinense in Favorable Use for Ten Years). Tokyo, Japan: Shufu no Tomosha.
• Shufo no Tomosha (1963). Kuko no koyo (Medicinal and Therapeutic Effects of Lycium chinense). Tokyo, Japan.
• Takayama, Eiji (1966). Jinsei no Honbutai wa Rokujissai Kara: Furo Choju Kuko no Aiyo (The Real Stage in Life Begins at Sixty: Habitual Use of Lycium chinense for Longevity). Tokyo, Japan: Koyo Shobo
• Zhang, Yanbo (2000). Molecular Approach to the Authentication of Lycium barbarum and its Related Species. M. Phil. thesis. Hong Kong, China: Hong Kong Baptist University
• Zhao, Yue (2005). The Market Prospect of Ningxia Wolfberry/Wolfberry Products in China. Thesis. Netherlands: University of Professional Education Larenstein Deventer.