Süstemaatiline kuuluvus (APG IV)
Riik: Taimed (Plantae)
Klaad: Soontaimed (Tracheophyta)
Klaad: Katteseemnetaimed (Angiospermae)
Klaad: Üheidulehelised (Monocotyledon)
Selts: Kõrreliselaadsed (Poales)
Sugukond: Kõrrelised (Poaceae)
Perekond: Sidrunhein (Cymbopogon)
Liik: Harilik sidrunhein - Cymbopogon citratus (DC.) Stapf

Botaaniline kirjeldus
Sidrunhein on troopilises kliimas kasvav kõrreline. Sidrunheina siledad sinakasrohelised lehed koosnevad lühikesest suletud lehetupest ja pikast avatud lehelabast, mis kasvab kuni 150 cm pikkuseks ja ripub otsast allapoole. Risoom on lühike, valge või helelilla. Teravate servadega lehed, mis lõhnavad aromaatselt sidruni järele, kui neid sõrmede vahel hõõruda, moodustavad kuni 120 cm kõrgusi puhmaid. Lehtede alus on paksenenud, sest noorima lehe tupest kasvavad välja uued lehed. Nii tekib sibulataoliselt üksteise sees paiknevatest lehtedest ring, kusjuures kõige vanemad lehed on väljaspool. Vaid harva moodustab sidrunhein tähkjaid õisikuid, enamasti paljuneb ta vegetatiivselt, võsudega. Õied on väikesed ja silmapaistmatud. Õitseb märtsist aprillini. Viljad on väikesed piklikud terised. [1]

Levila
Sidrunhein kasvab troopilistel ja lähistroopilistel Aasia, Aafrika ja Lõuna-Ameerika aladel. Taim eelistab kuiva ja hästiharitud mulda nig päikesepaistelist kasvukohta. [2]

Toime ja kasutus
Harilikku sidrunheina kasutatakse laialdaselt kulinaarsetel eesmärkidel, eriti Aasia köögis, kus see annab toitudele sidrunise ja värskendava maitse. Samuti on see populaarne ravimtaim, mida tarvitatakse teedes ja eeterliku õlina erinevate terviseprobleemide, nagu seedehäired ja stressi leevendamiseks. Uuringud näitavad, et sidrunheinal on antibakteriaalne, kõhulahtisusevastane, soolenugiliste -, seene-, amööbi- ja põletikuvastane toime. [2] Rakukultuuris on tähendatud tsütotoksilist toimet kasvajarakkudele [5] In vitro omab sidrunheina eeterlik õli plasmoodiumivastast toimet ja omab seega potentsiaali malaariavastases võitluses. Eeterliku õli kasutatakse ka sääskede peletamiseks.  [4] Ürt (kuivatatud lehed) sisaldab umbes 1–2% eeterlikku õli, mille bioaktiivsed keemilised koostisosad varieeruvad sõltuvalt keskkonnatingimustest, milles taim kasva. Eeterlik õli sisaldab tsitraali (terpenoidide ja geraniaali segu), genariooli, tsitronellooli ja α-oksobisabolooli. [6] 

Droogiks on eeterlik õli, mille tarbeks kogutakse ürti, mis destilleeritakse veeauruga. Ürti ja eeterlikku õli tarvitatakse nõrgalt kootava ja seedimist soodustava vahendina. Seda võetakse sisse seedehäirete puhul, aga ka külmetushaiguste korral. Korraga võetakse 3-6 tilka eeterlikku õli, mis tilgutatakse suhkrutükile. [8]

Kasutatud allikad
1. Ranade, S. S., & Thiagarajan, P. (2015). Lemon grass: An aromatic medicinal grass with potent pharmacognostic applications. International Journal of Pharmaceutical Sciences Review and Research, 35(2), 162-167. Retrieved from www.globalresearchonline.net
2. Shah, G., Shri, R., Panchal, V., Sharma, N., Singh, B., & Mann, A. S. (2011). Scientific basis for the therapeutic use of Cymbopogon citratus, stapf (Lemon grass). Journal of advanced pharmaceutical technology & research, 2(1), 3–8. https://doi.org/10.4103/2231-4040.79796
3. Bayala, B., Bassole, I. H. N., Maqdasy, S., Baron, S., Simpore, J., & Lobaccaro, J. A. (2018). Cymbopogon citratus and Cymbopogon giganteus essential oils have cytotoxic effects on tumor cell cultures. Identification of citral as a new putative anti-proliferative molecule. Biochimie, 153, 162–170. https://doi.org/10.1016/j.biochi.2018.02.013
4. Kpoviessi, S., Bero, J., Agbani, P., Gbaguidi, F., Kpadonou-Kpoviessi, B., Sinsin, B., Accrombessi, G., Frédérich, M., Moudachirou, M., & Quetin-Leclercq, J. (2014). Chemical composition, cytotoxicity and in vitro antitrypanosomal and antiplasmodial activity of the essential oils of four Cymbopogon species from Benin. Journal of ethnopharmacology, 151(1), 652–659. https://doi.org/10.1016/j.jep.2013.11.027
5. Bassolé, I. H., Lamien-Meda, A., Bayala, B., Obame, L. C., Ilboudo, A. J., Franz, C., Novak, J., Nebié, R. C., & Dicko, M. H. (2011). Chemical composition and antimicrobial activity of Cymbopogon citratus and Cymbopogon giganteus essential oils alone and in combination. Phytomedicine : international journal of phytotherapy and phytopharmacology, 18(12), 1070–1074. https://doi.org/10.1016/j.phymed.2011.05.009
6. Oladeji, O. S., Adelowo, F. E., Ayodele, D. T., & Odelade, K. A. (2019). Phytochemistry and pharmacological activities of Cymbopogon citratus: A review. Scientific African, 6, e00137. https://doi.org/10.1016/j.sciaf.2019.e00137
7. Raal, A. (2010). Maailma ravimtaimede entsüklopeedia. Tallinn: Eesti Entsüklopeediakirjastus

Classification (APG IV)
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Clade: Commelinids
Order: Poales
Family: Poaceae
Genus: Cymbopogon
Species: Lemon grass - Cymbopogon citratus (DC.) Stapf

Botanical description
Lemon grass is a grass that grows in tropical climates. The smooth, bluish-green leaves of lemongrass consist of a short, closed sheath and a long, open blade, which grows up to 150 cm long and hangs downward at the tip. The rhizome is short, white, or pale purple. The sharp-edged leaves, which emit a lemon-like aroma when rubbed between fingers, form clumps up to 120 cm high. The base of the leaves is thickened because new leaves emerge from the sheath of the youngest leaf. This creates an onion-like ring of overlapping leaves, with the oldest leaves on the outside. Lemongrass rarely forms spike-like inflorescences and mostly propagates vegetatively through shoots. The flowers are small and inconspicuous. It blooms from March to April. The fruits are small, elongated grains. [1]

Distribution
Lemon grass grows in tropical and subtropical regions of Asia, Africa, and South America. The plant prefers dry, well-cultivated soil and sunny growing conditions. [2]

Effects and uses
Lemon grass is widely used for culinary purposes, especially in Asian cuisine, where it imparts a lemony and refreshing flavor to dishes. It is also a popular medicinal herb used in teas and as an essential oil for various health issues, such as digestive problems and stress relief. Studies indicate that lemongrass has antibacterial, antidiarrheal, antiparasitic, antifungal, amoebicidal, and anti-inflammatory properties. [2] In cell culture studies, cytotoxic effects on tumor cells have been observed. [5] In vitro, lemongrass essential oil exhibits antiplasmodial activity, showing potential for use in combating malaria. The essential oil is also used as a mosquito repellent. [4] The herb (dried leaves) contains about 1–2% essential oil, with bioactive chemical components varying depending on the environmental conditions in which the plant grows. The essential oil contains citral (a mixture of terpenoids and geranial), geraniol, citronellol, and α-oxobisabolol. [6]

The essential oil is the main product, obtained by steam distillation of the harvested herb. Both the herb and the essential oil are used as mild astringents and digestive aids. It is taken internally for digestive issues and colds. A dose of 3–6 drops of essential oil is taken at a time, dripped onto a sugar cube. [8]

References
1. Ranade, S. S., & Thiagarajan, P. (2015). Lemon grass: An aromatic medicinal grass with potent pharmacognostic applications. International Journal of Pharmaceutical Sciences Review and Research, 35(2), 162-167. Retrieved from www.globalresearchonline.net
2. Shah, G., Shri, R., Panchal, V., Sharma, N., Singh, B., & Mann, A. S. (2011). Scientific basis for the therapeutic use of Cymbopogon citratus, stapf (Lemon grass). Journal of advanced pharmaceutical technology & research, 2(1), 3–8. https://doi.org/10.4103/2231-4040.79796
3. Bayala, B., Bassole, I. H. N., Maqdasy, S., Baron, S., Simpore, J., & Lobaccaro, J. A. (2018). Cymbopogon citratus and Cymbopogon giganteus essential oils have cytotoxic effects on tumor cell cultures. Identification of citral as a new putative anti-proliferative molecule. Biochimie, 153, 162–170. https://doi.org/10.1016/j.biochi.2018.02.013
4. Kpoviessi, S., Bero, J., Agbani, P., Gbaguidi, F., Kpadonou-Kpoviessi, B., Sinsin, B., Accrombessi, G., Frédérich, M., Moudachirou, M., & Quetin-Leclercq, J. (2014). Chemical composition, cytotoxicity and in vitro antitrypanosomal and antiplasmodial activity of the essential oils of four Cymbopogon species from Benin. Journal of ethnopharmacology, 151(1), 652–659. https://doi.org/10.1016/j.jep.2013.11.027
5. Bassolé, I. H., Lamien-Meda, A., Bayala, B., Obame, L. C., Ilboudo, A. J., Franz, C., Novak, J., Nebié, R. C., & Dicko, M. H. (2011). Chemical composition and antimicrobial activity of Cymbopogon citratus and Cymbopogon giganteus essential oils alone and in combination. Phytomedicine: international journal of phytotherapy and phytopharmacology, 18(12), 1070–1074. https://doi.org/10.1016/j.phymed.2011.05.009
6. Oladeji, O. S., Adelowo, F. E., Ayodele, D. T., & Odelade, K. A. (2019). Phytochemistry and pharmacological activities of Cymbopogon citratus: A review. Scientific African, 6, e00137. https://doi.org/10.1016/j.sciaf.2019.e00137
7. Raal, A. (2010). Maailma ravimtaimede entsüklopeedia. Tallinn: Eesti Entsüklopeediakirjastus