encyclopedia

Hops and Lupulin

Scientific Names:     

Humulus lupulus L. [Cannabaceae]     

Forms:     

Infusions and extracts of hops strobiles; lupulin extracts from hops grains.     

Traditional Usage:     

– Anxiety
– Appetite Loss
– Digestive Problems
– Gynecological Aid
– Hyper-excitability
– Insomnia
– Intestinal Cramps
– Menopause
– Nervous Tension
– Restlessness
– Skin Abrasions
– Stress
– Tension Headache
– Ulcers
– Urinary System Conditions     

Overview:     

The female flowers of the hop plant, Humulus lupulus L. [Cannabaceae], have long been used as a preservative and flavoring ingredient in beer. The cultivation of hops dates back to at least 860 A.D., based on written records. The therapeutic use of hops for treating anxiety, insomnia and restlessness is first noted in Europe in the 9th century. It was introduced in England in the sixteen century but was soon banned by King Henry VIII whose public believed it spoiled the taste of drinks, caused melancholy and endangered the people. Young hops shoots can be eaten but it is the strobiles (oval-shaped, semi-transparent scales otherwise known as hops or hop cones) and grains that are used in medicinal teas and manufacturing beer. Hops are primarily used as a sedative and relaxant. Sleeping on a pillow filled with hops is believed to help insomnia. Although the only confirmed value for hops lies in its use for edginess and insomnia, this herb has also been used traditionally as a bitter to stimulate the appetite, increase the flow of digestive juices, and treat ulcers, skin abrasions, and bladder inflammation. Cherokee healers traditionally used hops as a sedative, antirheumatic, analgesic, gynecological aid for breast and womb problems, and kidney and urinary aid for gravel and inflammation. In India and China hops are recommended for treating restlessness associated with nervous tension, headache, indigestion, insomnia, intestinal cramps and lack of appetite. Hops are now recognized for their strong estrogenic activity and are being included in some herbal preparations for women for “breast enhancement.” A recent study found that the main phytoestrogen in hops, 8-Prenylnaringenin, competed strongly with 17ss-estradiol for binding to both the alpha- and ss-estrogen receptors. Another study showed that hops bind competitively to estrogen receptors and up-regulate progesterone receptor mRNA in cultured endometrial cells.     

Active Ingredients:     

Hop strobiles contain: 5-30% bitter substances including acylphloro-glucides, humulones, lupulones; essential oil containing mono- and sesquiterpenes (myrcene, linalool, farnesene, caryophyllene, etc.; more that 150 aroma substances have been identified; tannins; flavonoids including kaempferol and quercetin mono- and diglycosides; xanthohumol and other chalcones. Traces of phenol-carboxylic acids (ferulic and chlorogenic acids. Phytoestrogen flavonoids include: 8-prenylnaringenin, and structurally related hop flavonoids. 6-Prenylnaringenin, 6,8-diprenylnaringenin and 8-geranylnaringenin
At the base of the hop scales are two hard nuts covered in aromatic, yellow glands or grains called lupulin. Lupulin can also be found in the scales but to a lesser degree. To extract lupulin from hops, the strobiles are rubbed and the grains sifted. Bitter substances (acylphloro-glucides) present in the resin make up to 50-80% of the hop grains whereas they make up only 15-30% of the hops strobiles. The resin is differentiated into the light-petroleum-insoluble part (hard resin) and the light-petroleum-soluble part (alpha and beta soft resins). The most important part of the alpha-soft resin is the bitter substance humulone, while the beta-soft resin contains mainly lupulone, another bitter substance.

Suggested Amount:     

Tea: Pour (150 ml) of boiling water over 1-2 teaspoons of cut or powdered strobile or dry extract powder of hops (0.5g per single dosage). Steep 10-15 minutes then strain. Drink infusion 2 or 3 times a day and before going to bed. Other preparations can be taken correspondingly. 1 Teaspoon = 0.4 g.     

Drug Interactions:     

Combinations of hops infusions with all other sedative drugs can be beneficial; alcoholic extracts of hops, however, should be avoided with sedatives that are known to interact dangerously with alcohol.     

Contraindications:     

Hops are rich in estrogenic substances and may interfere with pre-existing hormonal therapy. In view of this, hops are contraindicated in the case of breast cancer until further research can determine their potential positive or negative effects.    

Side Effects:     

May cause dermatitis in some people.     

References:     

Blumenthal M, Goldberg A, Brinckmann J 2000. Herbal Medicine: Expanded Commission E Monographs. Copyright American Botanical Council. Publ. by Integrative Medicine Communications, 1029 Chestnut Street, Newton, MA 02464. Pp. 193-196.
 
Liu J, Burdette JE, Xu H, Gu C, van Breemen RB, Bhat KP, Booth N, Constantinou AI, Pezzuto JM, Fong HH, Farnsworth NR, Bolton JL. 2001. Evaluation of estrogenic activity of plant extracts for the potential treatment of menopausal symptoms.  J Agric Food Chem. 2001 May; 49(5): 2472-9.
 
Milligan SR, Kalita JC, Pocock V, Van De Kauter V, Stevens JF, Deinzer ML, Rong H, De Keukeleire D. 2000. The endocrine activities of 8-prenylnaringenin and related hop (Humulus lupulus L.) flavonoids. J Clin Endocrinol Metab. 2000 Dec; 85(12): 4912-5.
 
Wichtl, M and NG Bisset (Eds). 1994. Lupuli strobulus/glandula – Hops/Hop Grains. In Herbal Drugs and Phyto-pharmaceuticals. (English translation by Norman Grainger Bisset). CRC Press, Stuttgart, pp. 305-308.
 
Yilmazer M, Stevens JF, Deinzer ML, Buhler DR. 2001. In vitro biotransformation of xanthohumol, a flavonoid from hops (Humulus lupulus), by rat liver microsomes. Drug Metab Dispos. 2001 Mar; 29(3): 223-31.