As diferentes ervas-cidreira e seus efeitos medicinais
Quais as duas ervas cidreira mais comuns? Quais suas propriedades clínicas?
Erva-cidreira verdadeira
Erva-cidreira é popularmente muito bem conhecida e é amplamente utilizada por conta do seu sabor agradável, aromático; e costuma ser um recurso caseiro contra cólicas intestinais, gases e como calmante. Essas propriedades terminaram sendo comprovadas pelas modernas experiências médicas.
No caso, dos dois tipos chamados popularmente de erva-cidreira possuem propriedades semelhantes. Estes dois tipos de “erva-cidreira” são, na verdade, duas famílias ou espécies diferentes, mas com atividades bioquímicas semelhantes (embora não iguais).
A melissa (Melissa officinalis), uma pequena planta aromática é considerada como a erva-cidreira verdadeira, e sua origem é européia,ao passo que aquele arbusto que popularmente nós conhecemos como erva-cidreira é a erva-cidreira falsa (Lippia alba), nativa do continente americano; as propriedades medicinais das duas são semelhantes e ambas possuem aroma agradável.
Lippia alba ou erva-cidreira falsa
A erva-cidreira verdadeira, ou melissa, européia de origem, é da família das labiadas e há bem mais pesquisas sobre ela; a “brasileira”, ou erva-cidreira falsa, foi menos estudada, é de outra família (verbenáceas), sendo nativa em quase todo o Brasil, ao contrário da melissa, mais cultivada nos climas do Sul e Sudeste. A erva-cidreira falsa também é conhecida como cidreira brasileira e erva-cidreira de arbusto.
Tanto uma como outra destas duas ervas pode ser utilizada sem problemas para pequenas cólicas intestinais e menstruais, também por seu leve efeito calmante. Assim como para excesso de gases. Ambas são levemente anti-espasmódicas.
Melissa officinalis ou erva-cidreira verdadeira
Estudos científicos identificaram propriedades antimicrobianas, antifúngicas, analgésicas, inseticidas, sedativas, relaxantes, ansiolíticas, anestésicas, antioxidantes, espasmolíticas, emenagogas e carminativas na erva-cidreira falsa [B]. E propriedades anticoagulantes [antitrombóticas] também na erva-cidreira falsa [E], assim como antifúngicas, em estudo de 2016 [F].
A dose é sempre a mesma: infusão de uma xícara de água fervente para 1 colher de sopa da folha fresca cortada ou então da folha seca e moída (deixar em repouso). Costuma ser usada algumas vezes ao dia.
Lippia alba ou erva-cidreira falsa
Não são tóxicas em uso moderado, apenas não foram bem estudadas em relação a outras propriedades medicinais que elas certamente possuem (o que significa que podem ser mais curativas do que parecem).
Não devem ser confundidas com o capim-limão [Cymbopogon citratus] que alguns chamam de erva-cidreira [ou de capim-cidreira].
Cymbopogon citratus ou capim-cidreira
A erva-cidreira verdadeira (melissa) possui ação virostática (anti-viral) comprovada contra o vírus da herpes labial. E pode ser usada em palpitações benignas [C]. Há estudos sobre o uso da melissa em ansiedade moderada. E em desordens sexuais e, em alguns casos, depressão e dificuldades do sono [G].
[Ver vídeo abaixo - A - que ilustra muito bem a diferença entre as ervas cidreira]
A erva-cidreira “brasileira” (ou falsa) se divide em três tipos de acordo com a forma de suas folhas e flores e, também, de acordo com suas propriedades medicinais (decorrentes da presença de determinado óleo aromático).
Os três tipos são calmantes e contra dor intestinal leve, mas um deles é mais sedativo que os outros, outro é mais analgésico e o terceiro é o único que tem propriedades expectorantes.
O mais fácil de reconhecer a olho nu é o tipo mais analgésico (maior teor do óleo essencial mirceno) porque ele tem as folhas e inflorescências maiores; os outros dois tipos têm a mesma aparência: folhas e inflorescências menores e só podem ser diferenciados pela composição química (um tem mais teor do óleo aromático limoneno, daí ser mais eficaz contra nervosismo e ansiedade; o outro tem maior teor do óleo essencial carvona, daí ser eficaz contra o muco dos brônquios, é expectorante).
Não se deve confundir erva-cidreira com capim-cidreira (Cymbopogon citratus); este, é de outra espécie (e pertence à família das gramíneas), é também conhecido como capim-limão, e embora tendo propriedades medicinais bem semelhantes às da erva-cidreira (calmante e espasmolítico suave, chegando a ser até mais eficaz que as ervas-cidreiras como calmante) mas tem certas propriedades anti-microbianas. Não é tóxico, em todo caso, e foi relativamente bem estudado. Com suas folhas frescas e cortadas, se faz um bom refresco, à base de suco de laranja doce, servido gelado (e bem coado: SEMPRE tem que ser bem coado, uma vez que pedacinhos das suas folhas podem agredir a mucosa do tubo digestivo mecanicamente).
Capim-cidreira
Tampouco se deve confundir a erva-cidreira que estamos analisando aqui com o cidró, que basicamente só existe no Sul e lá também é conhecido como erva-cidreira; o cidró também tem propriedades semelhantes às das demais erva-cidreiras (e às do capim-cidreira), por conta da presença de óleos essenciais tipo citral e limoneno, mas também tem poderes inseticidas. E pertence à família das verbenáceas (é a Aloysia triphylla).
As anotações acima sobre as duas erva-cidreira devem ser tomadas apenas como introdutórias. Podem ser feitos estudos na base de dados do PubMed e outras fontes, para quem quiser aprofundar o tema.
GMF, Brasília, 28-2-2023
Referências ________________
[A] Video ilustrativo Disponivel no Facebook – Diferenças entre a L.alba, melissa e o capim limão: https://www.facebook.com/Lippia-alba-Erva-cidreira-1917155154997751/videos/diferen%C3%A7as-entre-a-lippia-alba-melissa-e-o-capim-lim%C3%A3o/264324487527882/?locale=pt_BR
[B] http://www.unirio.br/ccbs/ibio/herbariohuni/lippia-alba-mill-n-e-br-ex-britton-p-wilson
[C] ALIJANIHA F, NASERI M, 2015. Heart palpitation relief with Melissa officinalis leaf extract: double blind, randomized, placebo controlled trial of efficacy and safety. J Ethnopharmacol . 2015 Apr 22;164:378-84. . Epub 2015 Feb 11. “Heart palpitation is a common complaint that is often benign and associated with a marked distress that makes the condition difficult to treat. Herbal medicines provide an alternative to conventional drugs for treating various kinds of diseases. This study was done as a double blind randomized placebo-controlled clinical trial to evaluate the efficacy and safety of the dried extract of M. officinalis on adults suffering from benign palpitations. Results: Fifty-five volunteers out of 71 recruited study subjects completed the trial. Results showed that 14-day of treatment with lyophilized aqueous extract of M. officinalis leaves reduced frequency of palpitation episodes and significantly reduced the number of anxious patients in comparison to the placebo (P=0.0001, P=0.004 resp.). Also, M. officinalis extract showed no indication of any serious side effects. Conclusion: Lyophilized aqueous extract of M. officinalis leaves may be a proper and safe herbal drug for the treatment of benign palpitations”. Disponível em: https://pubmed.ncbi.nlm.nih.gov/25680840/
[D] SHAKERI A, SAHEBKAR, A, 2016. Melissa officinalis L. - A review of its traditional uses, phytochemistry and pharmacology J Ethnopharmacol . 2016 Jul 21;188:204-28. . Epub 2016 May 7. “Ethnopharmacological relevance: Melissa officinalis L. is a medicinal plant that has long been used in different ethno-medical systems especially in the European Traditional Medicine and the Iranian Traditional Medicine for the treatment of several diseases. It is also widely used as a vegetable and to add flavor to dishes Aim of the review: This review aimed to provide a summary on the botanical characterization, traditional uses, phytochemistry, pharmacological activities, pharmacokinetics and toxicity of M. officinalis, and discusses research gaps and future opportunities for investigations on this plant. Materials and methods: We extensively reviewed major unpublished old texts, and published and electronic literature on traditional medicines of different regions of the world to find traditional uses of M. officinalis. Electronic databases including Web of Science, PubMed, ScienceDirect, Google Scholar and Scopus were searched to find articles (published between 1956 and 2015) on pharmacology and phytochemistry of M. officinalis. Results: Traditional uses of M. officinalis have been recorded mostly in European countries, Mediterranean region and Middle East countries. Phytochemical investigations revealed that this plant contains volatile compounds, triterpenoids, phenolic acids and flavonoids. Crude extracts and pure compounds isolated from M. officinalis exhibited numerous pharmacological effects, from which only anxiolytic, antiviral and antispasmodic activities of this plant as well as its effects on mood, cognition and memory have been shown in clinical trials. AChE inhibitory activity, stimulation of the acetylcholine and GABAA receptors, as well as inhibition of matrix metallo proteinase-2 are the main mechanisms proposed for the widely discussed neurological effects of this plant. Conclusions: Modern pharmacological studies have now validated many traditional uses of M. officinalis. The data reviewed here revealed that M. officinalis is a potential source for the treatment of a wide range of diseases especially anxiety and some other CNS disorders, though confirmatory trials are warranted to substantiate these effects in the clinical setting. Data regarding many aspects of this plant such as mechanisms of actions, pharmacokinetics, adverse effects of the extracts, potential interactions with standard-of-care medications and active compounds is still limited which call for additional studies particularly in humans”. Disponível em: https://pubmed.ncbi.nlm.nih.gov/27167460/
[E] LEITE, P M, MIRANDA A P N, 2023. Antithrombotic potential of Lippia alba: A mechanistic approach. J Ethnopharmacol . 2023 Jan 30;301:115744. . Epub 2022 Sep 29. “Ethnopharmacological relevance: Lippia alba (Mill.) N.E.Br. ex Britton & P. Wilson is traditionally used in Brazil as an adjunct in the relief of mild anxiety, as an antispasmodic, and as an antidyspeptic. This medicinal species was included in the Phytotherapeutic Form of the Brazilian Pharmacopeia 2nd edition (2021) and has already been described as the most used medicinal plant in a study with patients from an Anticoagulation Clinic in Brazil. Meanwhile, no studies were found that support the safety of the use of L. alba in patients using anticoagulants, a drug with several safety limitations. Aim of the study: Provide scientific evidence to ensure the safety of the concomitant use of L. alba and warfarin and support the management of these patients by evaluating its in vitro anticoagulant effect and chemical composition. And, as a timely complementation, evaluate the potential of this medicinal species in the development of new antithrombotics. Methods: The chemical profile of L. alba derivatives was analyzed by chromatographic methods such as Ultra-Performance Liquid Chromatography (UPLC) coupled with electrospray ionization mass spectrometry (ESI-MS), qualitative UPLC using Diode-Array Detection, and Thin Layer Chromatography. The anticoagulant activity was evaluated by the innovative Thrombin Generation Assay by Calibrated Automated Thrombogram method and using traditional coagulometric tests: prothrombin time, activated partial thromboplastin time, and plasma fibrinogen measurement. Results: Extracts and fractions prolonged the coagulation time in all the tests and reduced thrombin formation in thrombin generation assay. Coagulation times with the addition of ethanloic extract (2.26 mg/mL) was 17.78s, 46.43s and 14.25s respectively in prothrombin time, activated partial thromboplastin time and fibrinogren plasma measurement. In thrombin generation test, this same extract showed ETP as 323 nM/min compared to control (815 nM/min) with high tissue factor and 582 nM/min compared to control (1147 nM/min) using low tissue factor. Presence of flavonoids, phenylpropanoids, and triterpenes were confirmed by chromatographic methods and 13 compounds were identified by UPLC-ESI-MS. Based on these results and on the scientific literature, it is possible to propose that phenylpropanoids and flavonoids are related to the anticoagulant activity observed. Conclusion: The results demonstrate the in vitro anticoagulant activity of L. alba, probably due to the activation of intrinsic and extrinsic pathways. It is concluded, then, that there is a potential for interaction, which needs to be further studied, between L. alba and warfarin. Also, this medicinal species shows a great potential for use in the development of new antithrombotics”. Disponível em: https://pubmed.ncbi.nlm.nih.gov/36181984/
[F] SANTOS, N O, PASCON R C, 2016. Cytotoxic and Antimicrobial Constituents from the Essential Oil of Lippia alba (Verbenaceae) Medicines (Basel) . 2016 Aug 12;3(3):22.” Backgroud:Lippia alba (Verbenaceae) is a plant widely used in folk medicine to treat various diseases. The present work deals with the chemical composition of the crude essential oil extracted from leaves of L. alba and evaluation of its antimicrobial and cytotoxic activities. Methods: Leaves of L. alba were extracted by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) as well as by nuclear magnetic resonance (NMR) spectroscopy. Cytotoxic and antimicrobial activities of crude essential oil were evaluated in vitro using MTT and broth microdilution assays, respectively. Results: Chemical analysis afforded the identification of 39 substances corresponding to 99.45% of the total oil composition. Concerning the main compounds, monoterpenes nerol/geraniol and citral correspond to approximately 50% of crude oil. The cytotoxic activity of obtained essential oil against several tumor cell lines showed IC50 values ranging from 45 to 64 µg/mL for B16F10Nex2 (murine melanoma) and A549 (human lung adenocarcinoma). In the antimicrobial assay, was observed that all tested yeast strains, except C. albicans, were sensitive to crude essential oil. MIC values were two to four-folds lower than those determined to bacterial strains. Conclusion: Analysis of chemical composition of essential oils from leaves of L. alba suggested a new chemotype nerol/geraniol and citral. Based in biological evidences, a possible application for studied oil as an antifungal in medicine, as well as in agriculture, is described. Disponível em: https://pubmed.ncbi.nlm.nih.gov/28930132/
[G] ZAM W, QUISPE C, 2022. An Updated Review on The Properties of Melissa officinalis L.: Not Exclusively Anti-anxiety Front Biosci (Schol Ed) . 2022 Jun 7;14(2):16. “Melissa officinalis L. is a plant of the Lamiaceae family known in numerous countries for its medicinal activities. This plant has been used since ancient times to treat different disorders, including gastrointestinal, cardiovascular, neurological, psychological conditions. M. officinalis contains several phytochemicals such as phenolic acids, flavonoids, terpenoids, and many others at the basis of its pharmacological activities. Indeed, the plant can have antioxidant, anti-inflammatory, antispasmodic, antimicrobial, neuroprotective, nephroprotective, antinociceptive effects. Given its consolidated use, M. officinalis has also been experimented with clinical settings, demonstrating interesting properties against different human diseases, such as anxiety, sleeping difficulties, palpitation, hypertension, depression, dementia, infantile colic, bruxism, metabolic problems, Alzheimer's disease, and sexual disorders. As for any natural compound, drug, or plant extract, also M. officinalis can have adverse effects, even though the reported events are very rare and the plant can be considered substantially safe. This review has been prepared with a specific research strategy, interrogating different databases with the keyword M. officinalis. Moreover, this work analyzes the properties of this plant updating currently available literature, with a special emphasis on human studies”. Disponível em: https://pubmed.ncbi.nlm.nih.gov/35730441/
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