Mentha Longifolia Extract
Also known as: Horse mint, wild mint, wild bergamot, Mentha longifolia (L.) Huds., Mentha longifolia
Overview
Mentha longifolia, commonly known as horse mint, is a perennial herbaceous plant belonging to the Lamiaceae family, found across Europe, Asia, and North Africa. Traditionally, it has been utilized for its respiratory, digestive, and antimicrobial properties. Extracts can be prepared as aqueous, ethanolic, or essential oil forms, containing key bioactive compounds such as menthol, pulegone, and various flavonoids. Current research indicates its potential in alleviating respiratory symptoms, acting as an antimicrobial and antioxidant agent, and showing preliminary anticancer potential in vitro. While some clinical trials exist, particularly for respiratory benefits, comprehensive systematic reviews specifically on M. longifolia extract are limited, and more robust, large-scale randomized controlled trials are needed to solidify its evidence base.
Benefits
Mentha longifolia extract shows promise across several health areas. A randomized controlled trial (RCT) demonstrated significant improvement in clinical symptoms like fever, fatigue, chest pain, and cough in COVID-19 patients, with 50% achieving complete recovery within 7 days compared to 26.7% in controls. This suggests strong potential for respiratory symptom relief. The extract also exhibits robust antioxidant activity, which is beneficial for cellular health and may contribute to its use in pharmaceuticals and food preservation. Furthermore, it possesses antimicrobial properties against various pathogens, supporting its traditional use. In vitro studies indicate a dose-dependent cytotoxic effect on cancer cell lines, including breast cancer (MCF-7), showing up to 62.5% cell death at higher concentrations, though clinical evidence for anticancer effects is currently lacking. A meta-analysis on Mentha species (not exclusively M. longifolia) suggested a potential clinically meaningful reduction in long-term blood pressure, particularly for pre-hypertensive and hypertensive individuals, though short-term effects were not statistically significant.
How it works
The therapeutic effects of Mentha longifolia are primarily attributed to its rich composition of bioactive compounds, including menthol, pulegone, and flavonoids. These compounds contribute to its antioxidant activity by scavenging free radicals and inhibiting matrix metalloproteinases (MMPs), which are enzymes involved in inflammation and tissue remodeling. The antimicrobial properties are likely due to the direct action of these compounds on microbial cell structures or metabolic pathways. In cancer cells, the cytotoxic effects observed in vitro may involve the induction of apoptosis and inhibition of cell proliferation. For respiratory symptom relief, the extract is believed to exert anti-inflammatory and potentially bronchodilatory effects, although the precise molecular pathways in human respiratory systems require further investigation.
Side effects
Mentha longifolia is generally considered safe when consumed in traditional doses. However, caution is advised with concentrated extracts, particularly essential oils, due to the presence of pulegone. Pulegone is a known hepatotoxin at high doses, posing a risk of liver damage. No significant adverse effects were reported in a randomized controlled trial involving COVID-19 patients using an aqueous extract. Comprehensive data on drug interactions and contraindications for Mentha longifolia extract are limited. Therefore, individuals who are pregnant, breastfeeding, or have pre-existing liver conditions should exercise caution and consult a healthcare professional before use. Due to the lack of extensive safety data, it is prudent to adhere to recommended dosages and avoid excessive consumption, especially of highly concentrated forms.
Dosage
Specific standardized dosing guidelines for Mentha longifolia extract are not yet established. The randomized controlled trial on COVID-19 patients utilized an aqueous extract, but the precise dosage details were not specified in the available summary. Preclinical in vitro studies investigating anticancer effects used extract concentrations ranging from 500 to 2000 μg/mL. Given the variability in extract types (aqueous, ethanolic, essential oil) and their differing concentrations of bioactive compounds, dosing should ideally be based on standardized extracts and guided by clinical context. Absorption and bioavailability data for various forms of Mentha longifolia are limited, suggesting that aqueous extracts may have different pharmacokinetic profiles compared to essential oils. Due to the potential hepatotoxicity of pulegone in concentrated forms, upper limits and safety thresholds for long-term use, especially of essential oils, need further research.
FAQs
Is Mentha longifolia extract effective for respiratory infections?
Preliminary randomized controlled trial data suggest that aqueous M. longifolia extract can significantly improve clinical symptoms in COVID-19 patients, indicating potential for respiratory symptom relief.
Does Mentha longifolia extract lower blood pressure?
A meta-analysis on Mentha species suggests a possible clinically meaningful reduction in long-term blood pressure, but no statistically significant short-term effects have been observed.
Is Mentha longifolia extract safe to use?
It is generally considered safe in traditional use. However, caution is advised with concentrated essential oils due to the potential hepatotoxicity of pulegone at high doses.
How quickly can one expect to see benefits from Mentha longifolia extract?
In the COVID-19 RCT, significant symptom improvement was observed within 7 to 15 days of starting the aqueous extract.
Research Sources
- https://jbums.org/article-1-11724-en.pdf – This randomized controlled trial investigated the effect of aqueous Mentha longifolia extract on COVID-19 patients. It found that the extract significantly improved clinical symptoms and recovery rates compared to a control group, with 50% of the intervention group achieving complete recovery within 7 days. The study suggests M. longifolia as a potential adjunctive therapy for COVID-19 symptoms.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC7923432/ – This review summarizes the phytochemical composition and pharmacological activities of Mentha species, including M. longifolia. It highlights the strong antioxidant and antimicrobial properties of M. longifolia extracts and presents in vitro evidence of dose-dependent cytotoxicity against cancer cell lines, suggesting potential anticancer applications, though clinical data are lacking.
- https://pubmed.ncbi.nlm.nih.gov/39587518/ – This systematic review and meta-analysis evaluated the effect of Mentha species on blood pressure. It concluded that while there was no statistically significant short-term effect on blood pressure, there might be a clinically meaningful reduction in long-term blood pressure, particularly beneficial for pre-hypertensive and hypertensive patients. The review calls for more species-specific RCTs.