Humulus lupulus

Humulus lupulus is a perennial herbaceous plant up to {{Convert|10|m|abbr=off}} tall, living up to 20 years.{{Cite web |last1=Conway |first1=Sean |last2=Snyder |first2=Reid |date=2008 |title=Humulus lupulus - Hops |url=http://academics.hamilton.edu/foodforthought/Our_Research_files/hops.pdf |access-date=July 31, 2008 |website=College Seminar 235 Food for Thought: The Science, Culture, & Politics of Food |publisher=Hamilton College}} It has simple leaves with 3–5 deep lobes that can be opposite or alternate.{{Go Botany |genus=Humulus |species=lupulus |common=common hop, hops |access-date=2017-04-13}} The species is triggered by the longer summer days to flower,{{Cite web |title=HerbalGram: Hops (Humulus lupulus): A Review of its Historic and Medicinal Uses |url=http://cms.herbalgram.org/herbalgram/issue87/article3559.html?ts=1491676763&signature=2e9ee1bc86397f678c6439775de66cdd |access-date=2017-04-08 |website=cms.herbalgram.org }}{{Dead link|date=December 2024 |bot=InternetArchiveBot |fix-attempted=yes }} usually around July or August in the Northern Hemisphere.{{Cite web |title=Hop, Humulus lupulus - Flowers |url=http://www.luontoportti.com/suomi/en/kukkakasvit/hop |access-date=2017-04-13 |website=NatureGate}} The plant is dioecious, with male and female flowers on separate plants. The fragrant flowers are wind-pollinated.{{Cite web |title=Hops, Humulus lupulus, plant facts |url=https://www.edenproject.com/learn/for-everyone/plant-profiles/hops |access-date=2017-04-12 |website=Eden Project}} The staminate (male) flowers do not have petals, while the pistillate (female) flowers have petals enveloping the fruit. The female flower cones (or strobili) are known as hops. The fruit is an achene, meaning that it is dry and does not split open at maturity. The achene is surrounded by tepals and lupulin-secreting glands are concentrated on the fruit.{{cite web |title=Vitis riparia |url=http://climbers.lsa.umich.edu/?p=465 |website=CLIMBERS: Censusing Lianas in Mesic Biomes of Eastern Regions |first=Robyn J. |last=Burnham |date=2014 |publisher=University of Michigan College of Literature, Sciences and the Arts |access-date=2017-04-02}}{{Cite web|url=https://hort.purdue.edu/newcrop/duke_energy/Humulus_lupulus.html |title=Humulus lupulus |website=NewCROP, the New Crop Resource Online Program |access-date=2017-04-02}}

The species is sometimes described as a bine rather than a vine because it has stiff downward facing hairs that provide stability and allow it to climb.

H. lupulus contains myrcene, humulene, xanthohumol, myrcenol and linalool,{{cite journal |doi=10.1016/j.jep.2008.01.011 |title=Pharmacognostic and pharmacological profile of Humulus lupulus L |date=2008 |last1=Zanoli |first1=Paola |last2=Zavatti |first2=Manuela |journal=Journal of Ethnopharmacology |volume=116 |issue=3 |pages=383–396 |pmid=18308492 }} as well as less defined tannins and resin.

Hops are unique for containing secondary metabolites, flavonoids, oils, and polyphenols that impact the flavor of the products they are common in, such as beer.{{Cite journal |last1=Eriksen |first1=Renée L. |last2=Padgitt-Cobb |first2=Lillian K. |last3=Townsend |first3=M. Shaun |last4=Henning |first4=John A. |last12=Hendrix |first12=David A. |date=December 2021 |title=Gene expression for secondary metabolite biosynthesis in hop (Humulus lupulus L.) leaf lupulin glands exposed to heat and low-water stress |url= |journal=Scientific Reports |language=en |volume=11 |issue=1 |pages=5138 |bibcode=2021NatSR..11.5138E |doi=10.1038/s41598-021-84691-y |issn=2045-2322 |pmc=7970847 |pmid=33664420}} The bitter flavors in hops can be accounted for by acids composed of prenylated polyketides (a group of secondary metabolites), which highly impact the taste of hop-based products.{{Cite journal |last1=Goese |first1=Markus |last2=Kammhuber |first2=Klaus |last3=Bacher |first3=Adelbert |last4=Zenk |first4=Meinhart H. |last5=Eisenreich |first5=Wolfgang |date=1999-07-15 |title=Biosynthesis of bitter acids in hops. A 13C-NMR and 2H-NMR study on the building blocks of humulone |journal=European Journal of Biochemistry |volume=263 |issue=2 |pages=447–454 |doi=10.1046/j.1432-1327.1999.00518.x |issn=0014-2956 |pmid=10406953|doi-access=free }} Multiple genes have been identified as factors in the expression of taste including {{Nowrap|O-methyltransferase 1}}, geranyl diphosphate synthase, and chalcone synthase. Genomic analyses have shown evidence that the intervention of humans in the selection process of the hop over the thousands of years it has been cultivated have provided noticeable enhancements in aroma and bitterness as well as selection of varieties with high yield rates.{{Cite journal |last1=Natsume |first1=S. |last2=Takagi |first2=H. |last3=Shiraishi |first3=A. |last4=Murata |first4=J. |last5=Toyonaga |first5=H. |last6=Patzak |first6=J. |last7=Takagi |first7=M. |last8=Yaegashi |first8=H. |last9=Uemura |first9=A. |last10=Mitsuoka |first10=C. |last11=Yoshida |first11=K. |date=2014-11-20 |title=The Draft Genome of Hop (Humulus lupulus), an Essence for Brewing |journal=Plant and Cell Physiology |volume=56 |issue=3 |pages=428–441 |doi=10.1093/pcp/pcu169 |issn=0032-0781 |pmid=25416290 |doi-access=}}

File:Hop plant by Kent Ditch - geograph.org.uk - 5892896.jpg

Predicted genes in homologous primary contigs have been identified as accounting for various traits expressed via variation in the growth, flowering, and stress responses in the plant. These homologous primary contigs correspond to regions with large amounts of sequence variation. Genes in the hop that contain higher rates of sequence divergence in homologous primary contigs (overlapping DNA sequences inherited by a common ancestor) have been attributed to the expression of flowering, growth and responses to (both abiotic and biotic) stress in the plant. The responses to stress are thought to manifest in the distinct differences and difficulties in the cultivation processes between geographically popular varieties of the hop plant.{{Cite journal |last1=Padgitt-Cobb |first1=Lillian K. |last2=Kingan |first2=Sarah B. |last3=Wells |first3=Jackson |last4=Elser |first4=Justin |last5=Kronmiller |first5=Brent |last6=Moore |first6=Daniel |last7=Concepcion |first7=Gregory |last8=Peluso |first8=Paul |last9=Rank |first9=David |last10=Jaiswal |first10=Pankaj |last11=Henning |first11=John |last12=Hendrix |first12=David A. |date=2021-02-18 |title=A draft phased assembly of the diploid Cascade hop ( Humulus lupulus ) genome |journal=The Plant Genome |volume=14 |issue=1 |pages=e20072 |doi=10.1002/tpg2.20072 |issn=1940-3372 |pmid=33605092 |doi-access=free |s2cid=231962731}} Outside environmental stress, such as changes in temperature and water availability has also been shown to significantly alter the transcriptome and incite reductions in genes known to be involved in the synthesis of secondary metabolites (including bitter acids), which are organic compounds produced that do not impact development or reproduction of hops. Environmental stress has also been shown to reduce expression of the valerophenone synthase gene, which is known to be an essential genetic component in the regulation of bitter acid production. This shows that impacts of outside stress on H. lupulus likely has a direct implication of the expression of the bitter flavor that remains an essential component of the popularity of the plant.

• Humulus lupulus contains xanthohumol, which is converted by large intestine bacteria into the phytoestrogen 8-prenylnaringenin, which may have a relative binding affinity to estrogen receptors{{cite journal |vauthors=Milligan SR, Kalita JC, Heyerick A, Rong H, De Cooman L, De Keukeleire D |date=June 1999 |title=Identification of a potent phytoestrogen in hops (Humulus lupulus L.) and beer |journal=J Clin Endocrinol Metab |volume=84 |issue=6 |pages=2249–52 |doi=10.1210/jcem.84.6.5887 |pmid=10372741 |doi-access=free}} as well as potentiating effects on GABA_A receptor activity{{Cite journal |last1=Benkherouf |first1=Ali Y. |last2=Soini |first2=Sanna L. |last3=Stompor |first3=Monika |last4=Uusi-Oukari |first4=Mikko |date=February 2019 |title=Positive allosteric modulation of native and recombinant GABAA receptors by hops prenylflavonoids |journal=European Journal of Pharmacology |volume=852 |pages=34–41 |doi=10.1016/j.ejphar.2019.02.034 |issn=0014-2999 |pmid=30797788 |s2cid=73456325}}
• Humulus lupulus extract is antimicrobial, an activity which has been exploited in the manufacture of natural deodorant.{{cite web |title=Hops [CO2] Extract |url=http://www.tomsofmaine.com/products/ingredient-detail.aspx?id=110&name=Hops%20%5BCO2%5D%20extract |url-status=dead |archive-url=https://web.archive.org/web/20131224112745/http://www.tomsofmaine.com/products/ingredient-detail.aspx?id=110&%3Bname=Hops%20%5BCO2%5D%20extract |archive-date=December 24, 2013 |access-date=2009-06-06 |publisher=Toms of Maine}}
• Spent H. lupulus extract has also been shown to have antimicrobial and anti-biofilm activities, raising the possibility this waste product of the brewing industry could be developed for medical applications.{{cite journal |vauthors=Rozalski M, Micota B, Sadowska B, Stochmal A, Jedrejek D, Wieckowska-Szakiel M, Rozalska B |year=2013 |title=Antiadherent and Antibiofilm Activity of Humulus lupulus L. Derived Products: New Pharmacological Properties |journal=BioMed Research International |volume=2013 |pages=1–7 |doi=10.1155/2013/101089 |pmc=3794639 |pmid=24175280 |doi-access=free}}
• Extracts of the bitter alpha-acids present in H. lupulus have been shown to decrease nocturnal activity, acting as a sleep aide, in certain concentrations.{{Cite journal |last1=Franco |first1=L. |last2=Sánchez |first2=C. |last3=Bravo |first3=R. |last4=Rodriguez |first4=A. |last5=Barriga |first5=C. |last6=Juánez |first6=Javier Cubero |date=2012-06-01 |title=The sedative effects of hops (Humulus lupulus), a component of beer, on the activity/rest rhythm |journal=Acta Physiologica Hungarica |volume=99 |issue=2 |pages=133–139 |doi=10.1556/APhysiol.99.2012.2.6 |issn=0231-424X |pmid=22849837}}

Because of the growing understanding regarding the hop's overlap in gene structures with cannabidiolic acid synthase, the precursor structure to cannabidiol, there is a gap in general understanding about potential unknown compounds and benefits in hops. As the understanding of the health benefits available in cannabidiol increases, there is a growing demand to further investigate the overlap between cannabidiolic acid synthase and H. lupulus.{{Cite web |title=Advancing understanding of hop genome to aid brewers, medical researchers |url=https://www.sciencedaily.com/releases/2021/02/210222092258.htm |access-date=2021-04-09 |website=ScienceDaily |language=en}}

The genome of H. lupulus is relatively large and has been shown to be a similar size to the human genome. The complexity of the hop genome has made it difficult to understand and identify unknown genetic properties, however with the growing availability of accessible sequencing, there is room for more advanced understanding of the plant. Because of the growing concern of climate change, and the assumption that there will be an increase of heat waves, it is likely that growing large yields of hops could become more difficult. This could result in changes to the transcriptome of the hop, or result in a decrease of certain varieties, leaving less room for further research.

The hop is within the same family of plants such as hemp and marijuana, called Cannabaceae. The hop plant diverged from Cannabis sativa over 20 million years ago and has evolved to be three times the physical size.{{Cite journal |last1=Divashuk |first1=Mikhail G. |last2=Alexandrov |first2=Oleg S. |last3=Razumova |first3=Olga V. |last4=Kirov |first4=Ilya V. |last5=Karlov |first5=Gennady I. |date=2014-01-21 |title=Molecular Cytogenetic Characterization of the Dioecious Cannabis sativa with an XY Chromosome Sex Determination System |url= |journal=PLOS ONE |volume=9 |issue=1 |pages=e85118 |bibcode=2014PLoSO...985118D |doi=10.1371/journal.pone.0085118 |issn=1932-6203 |pmc=3897423 |pmid=24465491 |doi-access=free}}{{Cite journal |last1=Murakami |first1=A |last2=Darby |first2=P |last3=Javornik |first3=B |last4=Pais |first4=M S S |last5=Seigner |first5=E |last6=Lutz |first6=A |last7=Svoboda |first7=P |date=2006-05-10 |title=Molecular phylogeny of wild Hops, Humulus lupulus L. |journal=Heredity |volume=97 |issue=1 |pages=66–74 |doi=10.1038/sj.hdy.6800839 |issn=0018-067X |pmid=16685279 |doi-access=free |s2cid=11920277}}{{Cite journal |last1=Pisupati |first1=Rahul |last2=Vergara |first2=Daniela |last3=Kane |first3=Nolan C. |date=2018-02-21 |title=Diversity and evolution of the repetitive genomic content in Cannabis sativa |url= |journal=BMC Genomics |volume=19 |issue=1 |page=156 |doi=10.1186/s12864-018-4494-3 |issn=1471-2164 |pmc=5822635 |pmid=29466945 |doi-access=free }} The hop and C. sativa are estimated to have approximately a 73% overlap in genomic content.{{Cite journal |last1=Laverty |first1=Kaitlin U. |last2=Stout |first2=Jake M. |last3=Sullivan |first3=Mitchell J. |last4=Shah |first4=Hardik |last5=Gill |first5=Navdeep |last6=Holbrook |first6=Larry |last7=Deikus |first7=Gintaras |last8=Sebra |first8=Robert |last9=Hughes |first9=Timothy R. |last10=Page |first10=Jonathan E. |last11=van Bakel |first11=Harm |date=2018-11-08 |title=A physical and genetic map of Cannabis sativa identifies extensive rearrangements at the THC/CBD acid synthase loci |url= |journal=Genome Research |volume=29 |issue=1 |pages=146–156 |doi=10.1101/gr.242594.118 |issn=1088-9051 |pmc=6314170 |pmid=30409771}} The overlap between enzymes includes polyketide synthases and prenyltransferases.{{Cite journal |last1=Marks |first1=M. David |last2=Tian |first2=Li |last3=Wenger |first3=Jonathan P. |last4=Omburo |first4=Stephanie N. |last5=Soto-Fuentes |first5=Wilfredo |last6=He |first6=Ji |last7=Gang |first7=David R. |last8=Weiblen |first8=George D. |last9=Dixon |first9=Richard A. |date=2009-07-06 |title=Identification of candidate genes affecting Δ9-tetrahydrocannabinol biosynthesis in Cannabis sativa |url= |journal=Journal of Experimental Botany |volume=60 |issue=13 |pages=3715–3726 |doi=10.1093/jxb/erp210 |issn=1460-2431 |pmc=2736886 |pmid=19581347}} The hop and C. sativa also have significant overlap in the cannabidiolic acid synthase gene, which is expressed in the tissues of the leaves in both plants.

File:Humle (Humulus lupulus)-2017-Ystad.jpg 2017]]

File:Humulus lupulus 'Aurea' - Golden Hop.jpg

The five varieties of this species (Humulus lupulus) are:

• H. l. var. lupulus – Europe, western Asia
• H. l. var. cordifolius – eastern Asia
• H. l. var. lupuloides (syn. H. americanus) – eastern North America
• H. l. var. neomexicanus – western North American.{{PLANTS |symbol=HULUN |taxon=Humulus lupulus var. neomexicanus |access-date=May 5, 2016}}
• H. l. var. pubescens – midwestern and eastern North America{{GRIN |access-date=2018-07-31}}{{PLANTS |symbol=HULUP |taxon=Humulus lupulus var. pubescens}}

Many cultivars are found in the list of hop varieties. A yellow-leafed ornamental cultivar, Humulus lupulus 'Aureus', is cultivated for garden use. It is also known as golden hop, and holds the Royal Horticultural Society's Award of Garden Merit (AGM).{{cite web|url= https://www.rhs.org.uk/Plants/91715/Humulus-lupulus-Aureus/Details |title=Humulus lupulus 'Aureus' AGM|work=RHS Plant Selector|publisher=Royal Horticultural Society|access-date=25 August 2020}}{{cite web | url= https://www.rhs.org.uk/plants/pdfs/agm-lists/agm-ornamentals.pdf | title = AGM Plants - Ornamental | date = July 2017 | page = 43 | publisher = Royal Horticultural Society | access-date = 3 March 2018}}

The genus name Humulus is a medieval name that was at some point Latinized after being borrowed from a Germanic source exhibiting the h•m•l consonant cluster, as in Middle Low German homele.

According to Soviet Iranist Vasily Abaev this could be a word of Sarmatian origin which is present in the modern Ossetian language ({{langx|os|Хуымæллæг}}) and derives from proto-Iranian hauma-arayka, an Aryan haoma.Абаев В. И. Историко-этимологический словарь осетинского языка. Т. 4. М.—Л., 1989. С. 261-262.

From Sarmatian dialects this word spread across Eurasia, thus creating a group of related words in Turkic, Finno-Ugric, Slavic and Germanic languages (see {{langx|ru|хмель}}, Chuvash хăмла, Finnish humala, Hungarian komló, Mordovian комла, Avar хомеллег).

The specific epithet lupulus is Latin for "small wolf".{{Cite web |title=Humulus lupulus |url=http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=f191 |access-date=2017-04-12 |website=Plant Finder |publisher=Missouri botanical Garden}} The name refers to the plant's tendency to strangle other plants, mainly osiers or basket willows (Salix viminalis), like a wolf does a sheep. Hops could be seen growing over these willows so often that it was named the willow-wolf.

The English word hop is derived from the Middle Dutch word {{lang|dum|hoppe}}, also meaning Humulus lupulus.{{OEtymD|hop}}

The plant is native to Europe, western Asia and North America.

It grows best in the latitude range of 38°–51° in full sun with moderate amounts of rainfall.

The flowers attract butterflies, amongst other insects.

• Damson hop aphid (Phorodon humuli)
• Two spotted spider mite (Tetranychus urticae)
• Japanese beetle (Popillia japonica)
• Comma butterfly (Polygonia c-album)
• Pale tussock moth (Calliteara pudibunda)
• Currant pug moth (Eupithecia assimilata)
• Buttoned snout moth (Hypena rostralis)
• Buff ermine moth (Spilosoma lutea)

{{main|List of hop diseases}}

• Downy mildew (Pseudoperonospora humuli)
• Powdery mildew (Podosphaera macularis)

H. lupulus can cause dermatitis to some who handle them. It is estimated that about 1 in 30 people are affected by this.

{{main|Hops}}

H. lupulus is first mentioned in 768 CE when King Pepin donated hops to a monastery in Paris. Cultivation was first recorded in 859 CE, in documents from a monastery in Freising, Germany.{{Cite journal |last=Behre |first=Karl-Ernst |year=1999 |title=The history of beer additives in Europe - a review |url=https://www.researchgate.net/publication/226208521 |journal=Vegetation History and Archaeobotany |volume=8 |issue=1–2 |pages=35–48 |doi=10.1007/BF02042841 |bibcode=1999VegHA...8...35B |s2cid=129429552}}

The chemical compounds found in H. lupulus are the main components in flavoring and bittering beer. The fragrant flower cones, known as hops, impart a bitter flavor and also have aromatic and preservative qualities.{{cite journal |vauthors=Langezaal CR, Chandra A, Scheffer JJ |date=1992 |title=Antimicrobial screening of essential oils and extracts of some Humulus lupulus L. cultivars |journal=Pharm Weekbl Sci |volume=14 |issue=6 |pages=353–356 |doi=10.1007/bf01970171 |pmid=1475174 |s2cid=12561634}} Some other compounds help with creating foam in beer. Chemicals such as linalool and aldehydes contribute to the flavor of beer. The main components of bitterness in beer are iso-alpha acids, with many other compounds contributing to beer's overall bitterness.{{Cite journal|url=http://onlinelibrary.wiley.com/store/10.1002/j.2050-0416.2011.tb00471.x/asset/j.2050-0416.2011.tb00471.x.pdf?v=1&t=j1qr8dsg&s=f82746474fe24332c8d300aa8504f97861f3892b|doi=10.1002/j.2050-0416.2011.tb00471.x|title=125th Anniversary Review: The Role of Hops in Brewing|journal=Journal of the Institute of Brewing|volume=117|issue=3|pages=259–267|year=2011|last1=Schönberger|first1=C.|last2=Kostelecky|first2=T.|doi-access=free}} Until the Middle Ages, many varieties of plant were used to flavor beer, including most commonly Myrica gale. H. lupulus became favored because it contains preserving agents which prolong the viability of a brew.

Buds or hops of Humulus lupulus are used in Iranian ethnomedicine as a sedative.{{cite journal |last1=Buso |first1=Piergiacomo |last2=Manfredini |first2=Stefano |last3=Reza Ahmadi-Ashtiani |first3=Hamid |last4=Sciabica |first4=Sabrina |last5=Buzzi |first5=Raissa |last6=Vertuani |first6=Silvia |last7=Baldisserotto |first7=Anna |title=Iranian Medicinal Plants: From Ethnomedicine to Actual Studies |journal=Medicina |date=26 February 2020 |volume=56 |issue=3 |page=18 |doi=10.3390/medicina56030097|doi-access=free |pmid=32110920 |pmc=7143749 }}

H. lupulus was voted the county flower of Kent in 2002 following a poll by the wild flora conservation charity Plantlife.Plantlife website [http://www.plantlife.org.uk/wild_plants/county_flowers/ County Flowers page] {{webarchive|url=https://web.archive.org/web/20150430170312/http://www.plantlife.org.uk/wild_plants/county_flowers/ |date=2015-04-30 }}

{{Reflist}}

• "Czech hop varieties". Žatec: Chmelařský institut, 2012. [http://www.chizatec.cz/download/page5021.pdf on-line]
• Barchet, Ron. "German hops in craft brewing". Wolnzach: Hopfen-Rundschau, 2014.
• Biendl, Martin. "Hops and health". Wolnzach: German Hop Museum, 2013.
• Hieronymus, Stan. "For the love of hops: The practical guide to aroma, bitterness and the culture of hops". Boulder, CO: Brewers Publications, a division of the Brewers Association, 2012.
• Kopp, Sylvia. "Barley & hops: The craft beer book". Berlin: Gestalten, 2014.
• Melnychuk, M. D.; Boyko, A. L.; Hryhoryuk, I. P.; Likhanov, A. F.; Klyuvadenko, A. A.; Martyn, H. H.; Kukovenko, V. I. "Hop (Humulus lupulus L.): From cell to plant". Kyiv: Printeko, 2013.
• Nesvadba, Vladimír. "Development and tradition of Czech hop varietes". Žatec: Hop Research Institute, 2013.
• Neve, Ray A. "Hops". London: Chapman and Hall, 1991.
• Skomra, Urszula. "Polish hop cultivars". Puławy: Institute of Soil Science and Plant Cultivation, 2010.

{{Commons|Humulus lupulus}}

• [https://hort.purdue.edu/newcrop/duke_energy/Humulus_lupulus.html Purdue University article]
• [http://www.botanical.com/botanical/mgmh/h/hops--32.html Botanical.com - a wealth of information on the Hop plant and its past and modern uses]
• [http://www.armeniapedia.org/index.php?title=Humulus_lupulus Armeniapedia.org - Medicinal uses of hops in Armenia]
• 2005-10-25 Oregon State University [https://web.archive.org/web/20070121185641/http://oregonstate.edu/dept/ncs/newsarch/2005/Oct05/beerandcancer.htm Anti-cancer Compound in Beer Gaining Interest]

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{{Taxonbar|from=Q104212}}

lupulusa

Category:Plants described in 1753

Category:Taxa named by Carl Linnaeus

lupulus

Category:Cannabaceae

Category:Perennial plants