close
horehound plant

Horehound

Horehound also known as white horehound or Marrubium vulgare, is a plant with high bioactive potential that has been traditionally used in Europe and in southern and eastern Mediterranean countries. The most common traditional uses of white Horehound worldwide is for the treatment of gastrointestinal and respiratory disorders  such as acute or chronic bronchitis, colds and asthma 1, 2. Horehound plant is also traditionally used in cases where there is a lack of appetite or dyspepsia and for type 2 diabetes 1. White horehound is traditionally used in Morocco, Mexico, and Algeria in the treatment of diabetes mellitus 3.

White horehound is often confused with Black horehound (Ballota nigra or Marrubium peregrinum), which is also a traditionally used herbal substance with antiemetic (anti nausea and vomiting), sedative, and mild astringent properties 4, 5.

In the English language, the name ‘horehound’ comes from the Old English words har and hune, meaning downy plant. Horehound contains marrubiin, a labdane diterpene that is characteristic for this genus, as well as a complex mixture of phenolic compounds. According to numerous studies, Horehound acts as a good antioxidant agent, and due to this, it could potentially be useful in treatments of cancer, diabetes mellitus, and liver diseases 2. In addition, Horehound has even been used for anti-inflammatory, wound-healing, antihypertensive, hypolipidemic, and sedative therapy 2. Apart from that, its antimicrobial activity, especially against Gram+ bacteria, fungi, herpes simplex virus, and parasites such as Toxoplasma gondii, Trichomonas vaginalis, and Plasmodium berghei-berghei was recorded 2. Additionally, Horehound could be used as a chicken lice repellent, herbicide, and natural insecticide against mosquito larvae and natural molluscicide. In veterinary medicine, Horehound can be used as an anthelmintic against the eggs and larvae of bovine strongyles parasites, and as an antibiotic against bovine mastitis caused by resistant bacterial strains 2.

White horehound (Marrubium vulgare) is native to the Mediterranean sea region and widely distributed in many temperate regions of North Africa, Asia, and Europe 6. White horehound is a bushy spreading plant in a species of an annual or perennial herb in the family Lamiaceae (mint family) that grows to 75cm in height 7. The base of the stems is woody. The leaves are grey-green, roundish, with long hairs on the upper and lower surface and wavy edges. The veins are deeply impressed above and prominent below. giving it a crinkled appearance. The mature plant is erect and bushy in habit with stems which branch from the base and along their length and become woody. The top growth dies back, partially or completely, over winter but dead stems may persist for a considerable time. During colonization, the plant was introduced in America to great levels of popularity because of the simplicity of its growing; it was especially popular in Mexico and Brazil, where it has been known as ‘maromba’, ‘marroio’ or ‘marroio-branco’ 1.

Horehound plant is cultivated or gathered to obtain the above-ground parts (whole or fragmented dried flowering aerial plants of Marrubium vulgare) for medicinal use 8. White horehound preparations are obtained by comminuting (reducing into tiny pieces) or powdering the above-ground parts of the plant, by making a liquid extract or pressing the juice from the plant. Herbal medicines containing white horehound are usually available in a comminuted form for herbal tea, or in solid or liquid forms to be taken by mouth. White horehound can also be found in combination with other herbal substances in some herbal medicines.

White horehound can be applied as herbal tea for oral use (single dose: 1–2 g of herbal material in 250 mL of boiling water, as a herbal infusion, 3 times a day; daily: dose 3–6 g), powdered herbal substance (single dose: 225–450 mg, 3 times a day; daily dose: 675–1350 mg), expressed juice (single dose: 10–20 mL, 3 times a day; daily dose: 30–60 mL) and liquid extract (single dose: 1.5–4.0 mL, 3 times a day; daily dose: 4.5–12 mL) 2.

White horehound is a rich source of polysaccharides, amino acids, tannins, flavonoids, phenols, terpenes, alkaloids, and steroids 9. Numerous phytochemicals such as flavonoids (luteolin, ladanein, apigenin, quercetin, chrysoeriol, isoquercitrin, and vitexin), diterpenes (marrubiin and related compounds), phenylpropanoid esters (acteoside (or verbascoside), forsythoside B, ballotetroside, arenarioside, marruboside, alyssonoide, and marruboside), tannins (catechin, epicatechin, proanthocyanidins, and condensed tannins), and sterols have been isolated from white horehound 10. Several flavonoid glycosides and labdane diterpenoids have been isolated from the same source. The phytochemical investigation of white horehound produced a labdane diterpenoid, a glycosidic peregrinol, and a flavonoid derivative, in addition to apigenin-4’-O-(6’’-O-p-coumaroyl)-β-D-glucopyranoside, polyodonine, and 4’,5,7- trihydroxyflavone 2. Other compounds determined in the herbal material of white horehound are various nitrogen-containing compounds such as choline and betonicine, and alkaloid stachydrine, as well as minerals, in particular potassium salts 11.

White horehound produces trace amounts of essential oil, usually between 0.03% and 0.06% 12 with monoterpenes such as camphene, p-cymol, fenchene, limonene, α-pinene, sabinene, and α-terpinolene 13. Non-volatile monoterpene derivatives are also present in the plant with monoterpene marrubic acid and monoterpene glycoside sacranoside A (myrtenyl 6-O-α-l-arabinopyranosyl-β-d-glucopyranoside) as identified compounds 14. Sesquiterpene lactone vulgarin, β-sitosterole, lupeol, and β-amyrin types of triterpenoids such as oleanolic acid have been identified in white horehound extracts 15. White horehound accumulates diterpenes of labdane type as principle bitter components, up to 3 mg/g of fresh weight 16, with marrubiin being the predominant one (0.12–1%) followed by its precursor pre-marrubiin (0.13%), 12(S)-hydroxymarrubiin, 11-oxomarrubiin, 3-deoxo-15(S)-methoxyvelutine, marrubenol, marruliba-acetal, cyllenil A, polyodonine, and preleosibirin 17. In addition, peregrinol, peregrinin, dihydroperegrinin, vulgarol, vulgarcoside A, deacetylvitexilactone, carnosol, deacetylforskolin are present in diterpenoid fraction 18. The estimated content of marrubiin in the methanol extract of white horehound is 156 mg/g 19.

Figure 1. Horehound plant

horehound plant

Table 1. Quantification of phenolic and flavonoid content in white horehound

ExtractionPhenolic ContentFlavonoid ContentReferences
Aqueous extract175.00 mg gallic acid equivalents/100 g dry material23.86 mg quercetin equivalents/100 g dry material20
Aqueous infusionNot avalilable5.08 mg/100 mg dry material21
Ethanol–water extract (70:30, v/v)93.42 mg of gallic acid equivalents23.25 mg of rutin equivalent/g of extract22
Ethanol–water extract (70:30, v/v)59.87 mg gallic acid equivalents/g dry extract14.47 mg quercetin equivalents/g dry extract23
Methanol extract (dry)44.89 mg gallic acid equivalents/g dry extract24.60 mg quercetin equivalents/g dry extract24
Methanol extract48.97–195.00 mg gallic acid equivalents/g extract12.05–93.12 mg quercetin equivalents/100 g extract25
Microwave assisted extract61.44 mg of gallic acid equivalents/g of extract37.70 mg of rutin equivalent/g of extract22
Subcritical water extract72.98–85.20 mg gallic acid equivalents/g extract26.59–31.37 mg catechin equivalents/g extract26

Horehound uses

Horehound or white horehound (Marubium vulgare) has traditionally used for the treatment of inflammatory-related symptoms such as respiratory disorders  such as acute or chronic bronchitis, colds and asthma, fever, and sore throat 27, 1. Horehound plant is also used in cases where there is a lack of appetite or dyspepsia and for type 2 diabetes 1. Various white horehound herbal medicinal products are used as an expectorant in cough associated with cold, for symptomatic treatment of mild dyspeptic complaints, such as bloating flatulence, and in temporary loss of appetite 13.

The European Medicines Agency (Europe’s equivalent to the FDA) Committee on Herbal Medicinal Products concluded that, on the basis of its long-standing use, white horehound can be used in the following ways 8:

  • As an expectorant (a medicine to help bring up phlegm) in patients with cough associated with a cold. ‘Materia Medica Vegetabilis’ gave directions for the preparation of white horehound decoction with honey against bronchitis and coughs 28. Horehound herb is used to prepare the well-known horehound candy, which, due to its pleasant taste is used to relieve cough, hoarseness, and bronchitis.
  • For treating mild dyspepsia symptoms, such as bloating and flatulence;
  • In patients with a temporary loss of appetite.

White horehound should only be used in adults and adolescents aged over 12 years. If symptoms of cough persist for longer than one week, patients should consult a qualified healthcare practitioner. For dyspepsia and loss of appetite, patients are advised to consult healthcare practitioner if symptoms last longer than two weeks. Detailed instruction on how to take white horehound medicines and who can use them can be found in the package leaflet that comes with the medicine.

White horehound has a bitter value of 3.0, acting as the bitter gustative receptores (on the base of the tongue) stimulator. This effect leads to the increase in gastric and biliar secretion and the stimulation of appetite 29. White horehound is one of the most popular herbal ‘pectoral remedies’ (respiratory disorders) in traditional medicine, and it is used as a bitter tonic, expectorant, and diuretic 30. In addition to widespread use in the treatment of respiratory disorders, it has been reported that the folk use of white horehound includes treatment for jaundice, painful menstruation, and as a laxative in higher doses 31. Externally, White horehound is used for skin damage, ulcers, and wounds 32.

Horehound contains marrubiin, a labdane diterpene that is characteristic for this genus, as well as a complex mixture of phenolic compounds. According to numerous studies, Horehound acts as a good antioxidant agent, and due to this, it could potentially be useful in treatments of cancer, diabetes mellitus, and liver diseases 2. In addition, Horehound has even been used for anti-inflammatory, wound-healing, antihypertensive, hypolipidemic, and sedative therapy 2. Apart from that, its antimicrobial activity, especially against Gram+ bacteria, fungi, herpes simplex virus, and parasites such as Toxoplasma gondii, Trichomonas vaginalis, and Plasmodium berghei-berghei was recorded 2. Additionally, white Horehound could be used as a chicken lice repellent, herbicide, and natural insecticide against mosquito larvae and natural molluscicide. In veterinary medicine, white Horehound can be used as an anthelmintic against the eggs and larvae of bovine strongyles parasites, and as an antibiotic against bovine mastitis caused by resistant bacterial strains 2.

White horehound use as natural pesticides

In Spain, white horehound has been popularly used on chicken farms to prevent lice and frequent scratching of animals, which intensified its planting on farms 33. Moreover, a plant extract of white horehound was tested against fourth instar larvae of the mosquito Culex pipiens. The obtained results indicated a sensitivity of Culex pipiens larvae that was even higher when the exposure time of larvae to the insecticide is extended. The greatest mortality rate (94%) was achieved with 900 mg/L and a 72 hour exposure to white horehound extract, whereas a 59% mortality rate was achieved with 900 mg/L and a 72 hour exposure period. These results may provide an opportunity to develop alternatives to environmentally hazardous chemicals using some readily available, affordable plants which are mostly harmless to different living organisms 34. Furthermore, the volatile oil of white horehound has a remarkable toxicity on the snails of both Schistosoma mansoni and Schistosoma haematobium species 35. In addition, white horehound leaf extract and rizosphere soil extract significantly influence the seed germination and seedling growth of Sinapis arvensis and Latuca sativa in laboratory conditions. However, the allelopatic effects depend on target species. These extracts can be used as an important source of natural herbicides to control weeds in crop fields 24.

White horehound uses in Veterinary Medicine

The anthelmintic activities of ethanolic and aqueous extract of white horehound were evaluated using the egg hatch assay and larval mortality assay. After a 24 hour exposure period at a concentration of 50 mg/mL, the mortality rate was 45.8% for the aqueous extract and 51% for the ethanolic extract. These findings showed that white horehound extracts have potential anthelmintic effect on eggs and larvae of bovine strongyles parasites in vitro 36.

Bovine mastitis is the most serious diary problem in terms of economic losses to the dairy industry. With new generations of virulence and resistant bacteria, finding alternative treatments with medicinal plants to control these pathogenic strains is very popular. Among others, the ethanol extract of white horehound shows good antibacterial activity against methicillin-resistant staphylococci and multi-resistant Escherichia coli strains isolated from animals with mastitis manifestation 37.

Horehound potential medicinal uses

Antiplasmodial activity

The antiplasmodial activity of ethanolic extract of white horehound was evaluated in mice infected with chlorquine-sensitive Plasmodium berghei-berghei using curative, suppressive, and prophylactic experimental animal models. Preliminary phytochemical screening and intraperitoneal LD50 (50% lethal dose) estimation of the extract were carried out. In all doses tested, the extract produced significant curative and suppressive effects with minimal prophylactic effect. The extract also significantly prolonged the survival time of treated mice (up to 22 days), compared to the negative control group (11 days). The results of this study suggest that the ethanol extract of white horehound possesses curative and suppressive antiplasmodial activity in mice at all tested doses 38.

Antiparasitic activity

Toxoplasma gondii is a protozoan parasite that infects most species of warm-blooded animals, including humans, and causes the disease toxoplasmosis. While the Toxoplasma gondii parasite is found throughout the world, more than 40 million people in the United States may be infected with the Toxoplasma parasite. Toxoplasma gondii parasite infection usually occurs by eating undercooked contaminated meat, exposure from infected cat feces, or mother-to-child transmission during pregnancy. Toxoplasmosis may cause flu-like symptoms in some people, but most people affected never develop signs and symptoms. For infants born to infected mothers and for people with weakened immune systems, toxoplasmosis may cause serious complications. Using MTT (3-(4,5-dimethylthiazol-2-yl)-2–5-diphenyltetrazolium bromide) cell-proliferation assay in vitro, it was concluded that white horehound could be very useful against this parasite 39.

Antiprotozoal activity

Trichomonas vaginalis is a protozoan parasite that causes Trichomoniasis, a very common sexually transmitted disease (STD). The Trichomonas vaginalis parasite passes from an infected person to an uninfected person during sex. In women, the most commonly infected part of the body is the lower genital tract (vulva, vagina, cervix, or urethra). In men, the most commonly infected body part is the inside of the penis (urethra). During sex, the parasite usually spreads from a penis to a vagina, or from a vagina to a penis. It can also spread from a vagina to another vagina. Although symptoms of the disease vary, most people who have the parasite cannot tell they are infected. White horehound essential oil and extracts (n-hexane, ethyl acetate, and methanol) have potent antiprotozoal activity against Trichomonas vaginalis. After 48 hours of exposure, horehound essential oil with a minimal inhibitory concentration (MIC) value of 291 μg/mL showed the highest antiprotozoal activity, followed by ethyl acetate (541 μg/mL), methanol (1000 μg/mL), and n-hexane (1500 μg/mL). According to the findings of this study, the compounds of white horehound have a significant effect on Trichomonas vaginalis 40.

Antiviral activity

Herpes simplex virus type 1 (HSV-1) usually causes cold sores or fever blisters around your mouth. HSV-1 is often spread through skin-to-skin contact, though it can be spread to your genital area during oral sex. Recurrences are much less frequent than they are with herpes simplex virus type 2 (HSV-2) infection. Acute and recurrent herpes simplex virus type 1 (HSV-1) infections remain an important problem due to the emergence of acyclovir resistant virus. As a result of that, the search for novel antiviral bioactive compounds from plants has intensified in recent years. The antiviral activity of methanol, hexane, and chloroform extract of white horehound showed antiviral activity with selectivity indices of 3.11, 2.8, and 1.28, respectively 2. This study revealed that the hexane fraction disrupts the early steps of cyclic replication, including HSV-1 attachment, in a dose-dependent manner 41.

Antimicrobial activity

The antibacterial potential of different white horehound extracts (ethyl acetate, diethyl ether, and 1-butanol) was tested on four strains of bacteria: Staphylococcus aureus, Escherichia coli, Proteus vulgaris, and Pseudomonas aeruginosa 2. The antibacterial activity of different fractions performed on solid agar medium showed little or no effect. This implies that the antibacterial activity proved with crude extract of white horehound was likely induced by synergistic action in chemical ingredients present in the extracts 42. The methanolic extract of white horehound showed a significant antimicrobial activity against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Proteus vulgaris, and Candida albicans 43.

Moreover, one study was undertaken to determine the antifungal activity of flavonoids (flavans and flavanols) extracted from the leaves of white horehound against two fungal strains; Aspergillus niger ATCC 16,404 and Candida albicans ATCC 10,231 using the solid medium diffusion method. The minimum inhibitory concentrations (MICs) obtained range between 6.25 and 100 μg/mL and led to experiencing strong antifungal inhibition, which often exceeded the effect of marketed antifungals (amphotericin, fluconazole, terbinafine, and econazole nitrate) that marked white horehound flavonoids as potentially powerful antifungal agents 44. In addition, Rezgui et al. 45 concluded that white horehound and marrubiin can be used as antifungal agents for the treatment of skin dermatophyte infections. They examined the effect of acetone and methanol extracts, essential oil, and marrubin (all in two doses: 20 and 100 μg/mL) against the dermatophytes fungi Microsporum gypseum, Microsporum canis, Arthroderma cajetani, Trichophyton mentagrophytes, Trichophyton tonsurans, Epidermophyton floccosum, and against two fungi strains (Botrytis cinerea, Pythium ultimum).

White horehound essential oil has a significant effect on microorganisms, especially Gram(+) bacteria with inhibition zones and minimum inhibitory concentration (MIC) values in the range of 6.6–25.2 mm and 1120–2600 μg/mL, respectively, whereas Gram(–) bacteria exhibited higher resistance 2. When it comes to antifungal activity, among the four strains tested, Botrytis cinerea exhibited the strongest response to white horehound essential oil, with inhibition zones of 12.6 mm. However, Fusarium solani, Penicillium digitatum, and Aspergillus niger were less sensitive to white horehound essential oil 46.

Wound healing (hemostatic) properties

The study of use of methanolic extract of white horehound in wound reparation demonstrated that this extract, which was rich in poliphenolic compounds (flavonoids and several phenylethanoid glycosides) and marrubiin (6.62%), showed antioxidant and wound-healing properties by promoting cell migration and the proliferation of fibrosis 32. The assessment of hemostatic activity through the plasma recalcification method confirmed the surprising dose-dependent anticoagulant effect of aqueous extract of white horehound 20. A positive linear correlation between the studied parameters, content of condensed tannins, and hemostatic activity was used to highlight the potent vasoconstriction property of these compounds.

Gastroprotective activity

In the model of ethanol-induced ulcers, a significant reduction in all analyzed parameters was observed when white horehound extract was applied 47. The curative ratios were 49.31–74.31% for the groups treated with 50 and 100 mg/kg of white horehound extract. For indomethacin-induced ulcers, the percentages of ulcer inhibition were 50.32%, 66.24%, and 82.17% for the groups treated with 25, 50, and 100 mg/kg of white horehound. In both models, the marrubiin (25 mg/kg) produced a significant reduction in all parameters compared to the control group 2. There was also a significant increase in pH and mucus production in groups treated with white horehound extracts and marrubiin. The results demonstrated that the gastroprotective effect induced by these extracts and marrubiin is related to the activity of nitric oxide and endogenous sulfhydryls, which are important gastroprotective factors.

Antihypertensive activity

The water extract of white horehound is widely used as an antihypertensive treatment in folk medicine 2. Crude extracts of the aerial parts of white horehound show a potent in vitro inhibition of potassium chloride-induced contraction of rat aorta. Bioguided fractionations, spectroscopic analysis, and chemical derivatization revealed furanic labdane diterpenes, marrubenol, and marrubiin as the most active compounds 48, 49. By analyzing the effects that 10-week-long treatment with amlodipine (a calcium channel blocker drug used to treat hypertension) and white horehound water extract had on the systolic blood pressure, cardiovascular remodeling, and vascular relaxation in spontaneously hypertensive rats, it was observed that treatment with white horehound produced a decrease in systolic blood pressure. In addition, it had significant antihypertrophic effect in aorta and it improved acetylcholine (ACh)-induced relaxation of mesenteric artery. These results demonstrated that in addition to its antihypertensive effect, white horehound water extract improved the impaired endothelial function in spontaneously hypertensive rats 50.

Antidiabetic activity

White horehound has been used in Morocco, Mexico, and Algeria for the treatment of diabetes mellitus 51. Certain efforts have been made in order to obtain scientific evidence supporting its traditional use in diabetes mellitus control 10. Hellal et al. 52 performed in vitro (test tube tests) screening for the alpha-glucosidase inhibitory activity of six Algerian traditional medicinal plant extracts where white horehound 80% ethanol extracts exerted a moderate effect (IC50 = 12.66 μg/mL). Moreover, a series of in vivo experiments were carried out on alloxan-induced diabetes during which the experimental animals were treated twice a day with aqueous extract of white horehound for 15 days 21. Oral administration of 200 and 300 mg/kg body weight of white horehound aqueous extract induced significant dose-dependent antidiabetic and antihyperlipidemic effects. A dose of 100 mg/kg reduced blood glucose by 50%, whereas doses of 200 and 300 mg/kg showed more than 60% reduction of the same parameter. A decrease of total lipids, triglycerides, and cholesterol levels were observed in animals treated with white horehound when compared to the diabetic control group. Glibenclamide (a prescription drug that is used to treat type 2 diabetes) was used as a reference and showed similar effects, and the authors hypothesized that flavonoids and verbascoside derivatives present in examine extract caused the observed effects 21.

Chakir et al. 53 showed that the oral administration of white horehound methanolic extracts resulted in a significant lowering of blood glucose level, serum urea, uric acid, and creatinine, as well as a correction of lipid profiles when compared to streptozotocin-induced diabetic rats. These methanolic extracts significantly increased the glucose uptake of liver and skeletal muscles. Contrary to this, they reduced the glucose absorption in the everted rat jejunum. These results suggest that the effect of white horehound extract may be due to extrapancreatic mechanisms. This antidiabetic effect is an outcome of the modulation of glycogen synthesis and the inhibition of intestinal glucose absorption.

Another study 54 showed the effect of different white horehound extracts (methanol, water, and buthanol) on autoimmune diabetes mellitus induced by cyclosporine and streptozotocin. When compared to diabetic mice, the animals from the group treated with extracts of white horehound showed a decrease in blood glucose levels, pancreatic levels of interferon gamma (IFN-γ), and NO. white horehound extracts also caused a significant decrease in total cholesterol, low-density lipoprotein (LDL) cholesterol, very-low-density lipoprotein (VLDL) cholesterol, and triglycerides. Additionally, the serum insulin levels were significantly increased after treatment with white horehound.

In addition, Alkofahi et al. 55 screened 21 plants grown in Jordan for their antihyperglycemic activity on Sprague–Dawley rats at 1 g/kg where white horehound extract showed a neutral effect on blood glucose levels.

The incidence of atherosclerosis and cardiovascular diseases increases in diabetes mellitus patients. Therefore, the effects of white horehound on the contractile reactivity of isolated aorta were analyzed in an experimental model of streptozotocin-induced diabetic rats after two months of oral administration of white horehound 56. The results showed that serum glucose levels increased significantly in diabetic rats, while this increase was not observed in animals treated with white horehound. In addition, white horehound-treated rats showed a lower concentration of potassium chloride and noradrenaline in comparison to the control group. Based on these results, it was concluded that the oral administration of white horehound during 2 months could attenuate the contractile responsiveness of the vascular system, which may prevent the development of hypertension in diabetic rats.

Although there is an evident antihyperglycemic effect of white horehound extract on induced diabetes in experimental animals, the duration of these studies were short, and also another model of type 2 diabetes studies would be interesting to elucidate the exact mechanisms of action of this plant. In addition, there has been one clinical trial that contradicted findings from animal studies. Namely, aqueous extract (infusion of dried white horehound leaves) was tested to evaluate a clinical effect in 22 type 2 diabetic patients that had poor response to conventional treatment. The results showed that infusion reduced glucose levels by only 0.64%, cholesterol by 4.16%, and triglycerides by 5.78% 57. Finally, novel clinical trials are essential in order to confirm antidiabetic activity in humans as well as determine the right therapeutic protocol, potential adverse effects, and precautions.

Hypolipemic activity

One study evaluated the hypocholesterolemic and hypotriglyceridemic activities of four white horehound herb extracts (petroleum ether, chloroform, ethyl acetate, and methanol) using Triton WR-1339-induced hyperlipidemia in mice 58. Extracts were applied using 0.1 and 0.25 LD50 (50% lethal dose) concentrations. After 7 hour and 24 hour of treatment, the intragastric administration of all extracts caused a significant decrease of plasma total cholesterol; LDL cholesterol and triglyceride levels were also significantly lowered by all extracts. Additionally, more polar extracts (methanol and ethyl acetate) showed a significant ameliorative action on elevated atherogenic index and LDL/HDL-C ratios 58. These findings coincide with recorded decreases in the total cholesterol and LDL cholesterol levels during antidiabetic studies, which was probably due to a stimulation of the insulin secretion 59.

Moreover, since metabolic syndrome as a cluster of conditions includes increased blood pressure, high blood sugar, and abnormal cholesterol or triglyceride levels, all of which are influenced by white horehound herb extract, it would be useful to evaluate its possible usage as a part of nutrcaceuticals approach to this indication 60.

Sedative activity

The potential to reduce morphine withdrawal signs in animals had been studied using aqueous and ethanolic extracts of white horehound in different doses (0.1, 0.5, 1.5, and 2.5 g/kg). It was concluded that all doses reduced the physical activity of mice. They also induced muscle relaxation 61.

Immunomodulatory activity

The immunomodulatory effect of different concentrations of white horehound aqueous extracts (100, 500, and 1000 mg/kg body weight) was evaluated as a cure agent in mice previously infected with Salmonella typhimurium and as a protective agent in mice infested with Salmonella typhimurium 62. According to these results, the lowest concentration of white horehound (100 mg/kg body weight) showed high immunomodulatory effect in the level of double positive T cells, interleukin (17AIL-17) and interferon-gamma (IFN-γ).

Anti-inflammatory activity

Investigation of the anti-inflammatory effect of the methanolic extracts of white horehound on isoproterenol-induced myocardial infarction in a rat model showed that serum creatinine kinase-MB was subsided by 52.2–69.0% (depending on the dose of white horehound extract) 2. In addition, the treatment with extracts significantly reduced myocardial myeloperoxidase activity in myocardial infarction (heart attack) 63. Levels of tumor necrosis factor alpha (TNF-α) also declined considerably in the serums of rats with myocardial infarction. In addition, peripheral neutrophil count was significantly lowered by all doses of the extract. Interstitial fibrosis was significantly attenuated by treatment with white horehound compared to control. The results of this study demonstrated that white horehound extracts have strong protective effects against isoproterenol-induced myocardial infarction, and it seems possible that this protection is a result of its anti-inflammatory properties. Furthermore, the 11-oxomarrubiin, vulgarcoside A, and 3-hydroxyapigenin-4′-O-(6′′-O-p-coumaroyl)-β-d-glucopyranoside from the methanolic extract of white horehound exhibited moderate to low levels of inhibition on nitric oxide production, while vulgarcoside A also showed a moderate inhibition effect on pro-inflammatory cytokinine TNF-α 17. Glycosidic phenylpropanoid esters from white horehound showed inhibitory activity toward the cyclooxygenase (COX) enzyme, which plays a key role in the transformation of arachidonic acid into pro-inflammatory prostaglandins and is associated with inflammation 64.

The assessment of anti-inflammatory activity showed that the oral administration of methanolic extract of white horehound at a dose of 200 mg/kg in rats treated with carrageenin causes a significant decrease (87.30%) of inflammation compared to standard positive control (diclofenac), which showed 85.52% protection in this test 65. In a model of microvascular leakage in mice ears, the analysis shows that marrubiin from white horehound exhibits significant and dose-related antioedematogenic effects. The treatment of mice with marrubiin caused a dose-dependent inhibition of carregeenan, bradykinin, and histamine-induced extravasation of Evans blue in mice ears, with maximal inhibitions of 63.0%, 70.0%, and 73.7%, respectively. The other phlogistic agonists, such as prostaglandin E2, caused an inhibition of less than 50%. In addition, marrubiin significantly inhibited the ovalbumin-induced allergic edema in actively sensitized animals. These results demonstrate that the systemic administration of marrubiin exerts a non-specific inhibitory effect on pro-inflammatory agent-induced microvascular extravasation of Evans blue in mice ears 66. The evaluation of anti-inflammatory activities against inflammation induced by carrageenen and prostaglandin E2 and analgesic activity in the p-benzoquinone-induced abdominal constriction test showed that methanolic extracts of white horehound have a similar effect as reference drugs indomethacin and acetylsalicylic acid 43.

An in vitro investigation of the anti-inflammatory effect that six compounds from white horehound (luteolin-7-O-β-glucopyranoside, apigenin-7-O-β-glucopyranoside, oleanolic acid, β-sitosterol, luteolin-7-O-rutinoside, and rosmarinic acid) have on cyclooxygenase (COX) showed that these compounds inhibited the formation of hormones, such as prostaglandins and peroxasalandine, which contribute to the production of inflammatory intermediators 15.

Anti-cancer activity

White horehound are often used traditionally in cancer treatment 67, 1, but the exact mechanisms of action and scientific validity of their usage are yet to be discovered. Zarai et al. 46 reported the ability of white horehound essential oil to inhibit the proliferation of cervical cancer (HeLa) cell lines with an half-maximal inhibitory concentration (IC50) value of 0.258 μg/mL. White horehound ethanol–water extracts (70:30, v/v) reduced the viability of melanoma (B16) and glioma (U251) in a dose-dependent manner. By demonstrating the ability of white horehound extracts to inhibit proliferation, induce apoptosis, and cytoprotective autophagy, the results suggested that white horehound could be a good candidate for anti-melanoma and anti-glioma therapy 68. In addition, the methanolic extract of white horehound was evaluated for its in vitro cytotoxic activity by measuring the percentage of viable cells’ glioblastoma multiforme cell lines (U87, LN229 and T98G) using a luminescence system. After evaluating the cytotoxicity impact that white horehound has on U87 (IC50: 270.3 μM), LN229 (IC50: 343 μM), and T98G (IC50: 336.6 μM) from glioblastoma multiforme cell lines, it was concluded that it is the most efficient in two cell lines, U87 (69.9%) and LN229 (71%) 25.

The in vitro anticancer activity of white horehound ethanol–water extracts (90:10, v/v) and six pure compounds (acacetin, acacetin-7-rhamnoseide, apigenin, diosmetin, diosmetin-7-glucoside, and luteolin-7-rhamnoside) were also tested against Ehrlich tumor cell lines, human tumor cell lines U251 (brain tumor) and MCF7 (breast cell lines) 69. Alcoholic extracts, acacetin, apigenin, and acacetin-7-rhamnoside showed high anticancer activity against breast carcinoma, whereas all tested compounds had anticancer activity against Ehrlich tumor cell lines. Another study 70 showed that labdanein (methoxylated flavone) from white horehound displayed a moderate effect on human myeloid leukemia (K562) and imatinib-resistant human myeloid leukemia (K562R) cells, as well as on human B cell precursor leukemia cell lines (697). The authors of this study suggested that these results provide a common natural source for the hemi-synthesis of future ladanein-derived flavones and the study of their antileukemic activity. Tlili et al. 71 examine the effect of white horehound and other Tunisian plant extracts on leukemia and colon cancer cell lines (K-562 and CaCo-2, respectively). Subsequently, the anti-inflammatory activity was assessed, and the results showed that white horehound possesses the highest activity in the group of analyzed plants.

Kozyra et al. 72 investigated the potential anticancer activity of methanolic extracts phenolic acid (PhA) fractions of white horehound against a human melanoma cancer cell line (A375) and normal human skin fibroblasts (BJ) using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide test, cell cycle analysis, and real-time monitoring of cell viability. Surprisingly, examined fractions demonstrated a low total phenolic content and did not show significant antioxidative properties, but the nonhydrolyzed PhA fraction exhibited cytotoxic activity against a human melanoma cancer cell line, without affecting normal fibroblasts. Both acidic and alkaline hydrolysis abolished this activity, indicating that the esterified forms of phenolic compounds exhibit the observed cytotoxic effects. Since white horehound is abundant in phenylpropanoid (cinnamic) esters and phenylethanoid glycosides, further investigation of these compounds may provide an insight into the exact anticancer mechanism of action and use as a model for cancer treatment drug development.

Moreover, Shawky 73 used the network pharmacology approach to identify the main active constituents of North African plants against cancer molecular targets and to explore their therapeutic mechanism. White horehound possessed the largest number of plant–constituent–target gene interactions indicating cell cycle arrest and apoptosis in addition to the inhibition of cellular proliferation as possible mechanisms and marked this plant as a potential source for the supportive treatment of cancer.

Liver protection properties

Investigation of the hepatoprotective and therapeutic effect of ethanol–water extract (70:30, v/v) and petroleum ether extracts on carbon tetrachloride (CCl4)-induced liver cell toxicity in mice showed that liver and kidney function parameters remained in the normal levels in groups treated with white horehound extracts. The administration of white horehound ethanolic extracts significantly enhanced SOD (superoxide dismutase) and CAT (catalase) activity, as well as total antioxidant capacity, with significant reduction in lipid peroxide concentration when extracts were used as protective or therapeutic agents 74. The antihepatoxic activity of ethanol–water extracts (80:20, v/v) of white horehound in different concentrations (100, 200, 300, and 400 mg/kg) was assessed by measuring lipid profile parameters such as AST (aspartate aminotransferase), ALT (alanine aminotransferase), ALP (alkaline phosphatase), GSH (reduced gluthation), SOD, and malondialdehyde (MDA), as well as by histopathological examination of CCl4-induced liver damage in rats. Different concentrations of extracts showed a significant antihepatotoxic effect by reducing the levels of AST and ALT significantly, whereas the ALP level was insignificantly decreased. Regarding the antioxidant activity, these extracts exhibited a significant decrease in SOD and contents of GSH and MDA (a biomarker of membrane lipids peroxidation). These findings showed that different concentrations of white horehound extract protect liver against CCl4-induced hepatotoxicity, and the effect may be attributed to its antioxidant activity 75.

Methanol extracts of white horehound showed considerable antihepatotoxic effect by significantly reducing levels of AST, ALT, and LDH. However, the decrease in ALP levels was not significant. As for the antioxidant activity, white horehound extracts notably increased the GPx (glutathione peroxidases), GR (glutathione reductase), and GST (glutathione transferase) activities in rat liver tissue. In addition, it increased the GSH content and decreased the production of MDA level, adding to alleviated histopathological changes in rats’ livers treated with CCl4 76.

In another animal study 77, marrubic acid exhibited a significant antihepatotoxic activity by reducing the elevated levels of serum enzymes such as serum glutamate oxaloacetate transaminase (SGOT) by 40.16%, serum glutamate pyruvate oxaloacetate transaminase (SGPT) by 35.06%, and alkaline phosphatase (ALP) by 30.51%.

The hepatoprotective potential of 12 pure compounds (marrubiin, premarrubiin, vulgarin, luteol, vulgarol, apigenin-7-glucronide, vitexin, apigenin, chryseriol, stachydrine, acetoside, and 1-caffeory-L-malic acid) characteristic for white horehound were tested on CCl4-induced acute liver injury in rats through the in silico method. All compounds showed expected and similar bioactivity, especially when it comes to liver-associated enzymes inhibition 11.

Antioxidant activity

The imbalance in homeostatic processes between oxidants and antioxidants in the body, which is caused by free radicals, leads to oxidative stress. Oxidative stress is considered to be the primary cause of aging and a wide variety of human diseases, such as cancers, diabetes, neurodegenerative disorders, rheumatoid arthritis, etc. Antioxidants are substances that significantly delay, prevent, or inhibit oxidative damage to target molecules 78.

The in vitro antioxidant properties of white horehound methanol extracts were determined using DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging assay and the results revealed a strong activity with the half maximal inhibitory concentration (IC50) value of 8.24–12.42 μg/mL 65. The antioxidant activity investigated by the same method shows that white horehound essential oil exhibits IC50 value of 153.84 μg/mL, which is about two times higher than a synthetic antioxidant (butylated hydroxytoluene or BHT) 79. Photochemiluminescence (PLC) assay, evaluating the antioxidant activity of the compound in the presence of superoxide anion radical, reactive oxygen species (ROS) also generated in the human body, determined the strong antioxidant effect of methanol and acetone white horehound extracts (261.41 and 272.90 μmol TE/g respectively), while the lower activity was observed when essential oil and isolated marrubin were investigated 45. Djeridane et al. 80 determined that there is a good correlation of antioxidant potential and the content of phenolic compounds. Furthermore, acetone extracts, deodorized acetone extracts, and deodorized water extracts from white horehound leaves were tested for their antioxidant activity in rapeseed oil at 80 °C. The effect of the extracts on the edible oil stability was assessed by measuring weight gain, peroxide value, and UV absorption 81. Acetone extracts showed better antioxidant properties than deodorized acetone extracts. According to Yousefi et al. 19, the high antioxidant activity of white horehound was associated with the presence of marrubiin, along with phenolics and flavonoids exerting a synergistic effect.

In addition, white horehound methanolic extracts showed a dose-dependent ferric reducing capacity (Ferric Reducing Antioxidant Power Assay, or FRAP) with a value equal to 50.01 μg Ascorbic Acid Equivalents/g of extract when compared to ascorbic acid (AAE: Ascorbic Acid Equivalents) 65. Other authors 14, 23 reported that FRAP assay of ethanol–water extract of white horehound (70:30, v/v) showed IC50 of 64.07 mg AAE/g of dry extract and IC50 for the neutralization of DPPH, hydroxyl (OH), and nitroso (NO) radicals were 13.41, 63.99, and 64.86 μg/mL, respectively. Furthermore, inhibition on lipid peroxidation was examined in vitro 23, the results indicating the antiatherogenic potential of white horehound extracts.

Bouterfas et al. 2016 82 also determined the potent activity of white horehound extracts on DPPH radical but concluded that this effect varied significantly depending on the type of the organic solvent used for extraction and sampling location.

Lastly, all these finding indicate the antiradical potential of white horehound extracts using different in vitro tests, but research should be directed toward in vivo experiments in order to elucidate their full antioxidant capacity.

Horehound side effects

White horehound is generally recognized as safe in the USA, and it is widely used as a flavoring agent 2. White horehound side effects from the clinical trial involving type 2 diabetes patients included nausea, oral dryness, drooling or excessive salivation, dizziness, and anorexia, although they were not adverse enough to necessarily cause a withdrawal from the study 57.

Horehound toxicity

White horehound use in children under 12 years of age is not recommended 2. Safety during pregnancy and lactation has not been established 13. Furthermore, results showed that a group of normal rats treated with the ethanol–water extract of white horehound (80:20, v/v) and pregnant rats treated with the extract exhibited a significant decrease in hematological parameters: red blood cells, hematocrit, hemoglobin, and mean corpuscular volume 2. The extract of white horehound caused a significant decrease on the mean implantations of fetuses and their size. As for the macroscopic and histological appearance of uterus; these data showed no change in normal treated rats. Contrary to these, the treated pregnant rats showed a severe histological change characterized by interrupted gestation, as well as the lysing of placental and embryo tissue in the uterus. All these results support the hypothesis of an abortifacient effect of white horehound 83. Possibly, the furanic labdane diterpene marrubin and premarrubin could be responsible for these effects, since they are structural analogues with leosibiricin, an active diterpene of Leonorus cardiaca, which is a plant that is known for its emenagogue activity and contraindicated in pregnancy 16. Additionally, the effects of alcoholic extract of white horehound on hormonal parameters in a female rat model (receiving 500 mg/kg and 1000 mg/kg of white horehound extract for 21 days) of polycystic ovarian syndrome (PCOS) were studied. Luteinizing hormone (LH) hormone significantly decreased at a dose of 1000 mg/kg, and estradiol and progesterone decreased at doses of 500 mg/kg and 1000 mg/kg, while testosterone decreased at a dose of 1000 mg/kg. These findings contribute to the potential influence of examined extract on female hormones, thus questioning their safe usage in pregnancy 84. In addition, white horehound is mentioned in certain literature as a potentially nephrotoxic plant 85. However, there is no relevant scientific evidence to confirm these claims.

Horehound summary

White horehound has been used in the traditional medicine systems worldwide; but well designed clinical trials are needed to confirm the many traditional uses of white horehound herb preparations for the prevention and treatment of various ailments. The European Medicines Agency (Europe’s equivalent to the FDA) Committee on Herbal Medicinal Products concluded that, on the basis of its long-standing use, white horehound can be used in patients with cough, dyspepsia symptoms and loss of appetite are based on their ‘traditional use’. This means that, although there is insufficient evidence from clinical trials, the effectiveness of these herbal medicines is plausible and there is evidence that they have been used safely in this way for at least 30 years (including at least 15 years within the EU). Moreover, the intended use does not require medical supervision.

In its assessment the European Medicines Agency Committee on Herbal Medicinal Products considered the well documented and longstanding use of white horehound in the approved indications. The European Medicines Agency Committee on Herbal Medicinal Products noted that white horehound bitter substances and essential oils may stimulate appetite and secretions from the lining of the airways. In addition, there were published experimental studies suggesting a number of properties that could plausibly help in patients with mild dyspepsia.

Black horehound

Black horehound also known as Ballota nigra is a species of eudicot in the family Lamiaceae (mint family). Black horehound is native to the Mediterranean region and predominantly found in Europe and Asia 86. People in many parts of Turkey use the aerial parts of black horehound traditionally to treat haemorrhoids, wounds, ulcers, animal bites, sores, flu, colds, and flatulence, and as an antiseptic for inflamed skin, wounds, burns, and diabetes mellitus 87.

Table 2 shows the results of phytochemical evaluation of different parts of different extracts and subfractions of Black horehound (Ballota nigra). Numerous compounds such as 7α-acetoxymarrubiin, ballonigrin, ballotenol, ballotinone, dehydrohispanolone (hispanone), ballonigrin, ballotenol, ballotinone, marrubiin, preleosibirin, hydroxyballonigrolide, siderol, dehydrohispanolone, apigenin-7-glucoside, luteolin-7-glucosyl-lactate, luteolin-7-lactate, ladanein, vicenin-2, tangeretin, caffeic, caffeoylmalic, and chlorogenic acids were isolated from black horehound 86.

Table 2. Phytochemical analysis of Black horehound (Ballota nigra) (root, stem, and leaves)

Part usedExtractsAlkaloidsFlavonoidsTerpenesTanninsSaponinsPhenols
Black horehound (root)Crude+ + +
n-Hexane+
Chloroform+ + +
Ethyl Acetate+ + +
Butanol
Aqueous
Black horehound (stem)Crude+ + + + +
n-Hexane+
Chloroform+
Ethyl Acetate+ + +
Butanol+ + +
Aqueous
Black horehound (leaves)Crude+ + +
n-Hexane+
Chloroform+ + +
Ethyl acetate+ +
Butanol+ + +
Aqueous

Footnote: (−) sign shows absence of phytochemicals and (+) sign shows presence of phytochemicals.

[Source 88 ]

Black horehound uses

Black horehound (Ballota nigra) has traditionally has been used for nausea, vomiting, nervous dyspepsia and specifically for vomiting of central origin 4. Black horehound is commonly used for treating influenza and cough in western Europe 89. A 70% ethanol extract of Black horehound has been reported to possess hypoglycaemic, insulin-releasing, and cholesterol-lowering effects in rats 87. The whole plant of black horehound (Ballota nigra) is used in repellent fumigation against insects 90.

References
  1. Rodríguez Villanueva J, Martín Esteban J. An Insight into a Blockbuster Phytomedicine; Marrubium vulgare L. Herb. More of a Myth than a Reality? Phytother Res. 2016 Oct;30(10):1551-1558. doi: 10.1002/ptr.5661
  2. Aćimović, M., Jeremić, K., Salaj, N., Gavarić, N., Kiprovski, B., Sikora, V., & Zeremski, T. (2020). Marrubium vulgare L.: A Phytochemical and Pharmacological Overview. Molecules (Basel, Switzerland), 25(12), 2898. https://doi.org/10.3390/molecules25122898
  3. Boudjelal A, Henchiri C, Siracusa L, Sari M, Ruberto G. Compositional analysis and in vivo anti-diabetic activity of wild Algerian Marrubium vulgare L. infusion. Fitoterapia. 2012 Mar;83(2):286-92. doi: 10.1016/j.fitote.2011.11.005
  4. British Herbal Pharmacopoeia. British Herbal Medicine Association; Keighley: 1983.
  5. Berger F. Handbuch der Drogenkunde, Vol 4. Wilhelm Maudrich Verlag, Wien 1954, 339–342
  6. Lodhi S., Vadnere G.P., Sharma V.K., Usman M. Marrubium vulgare L.: A review on phytochemical and pharmacological aspects. J. Intercult. Ethnopharmacol. 2017;6:429. doi: 10.5455/jice.20170713060840
  7. Horehound (Marrubium vulgare). https://www.weeds.asn.au/tasmanian-weeds/view-by-common-name/horehound
  8. Marrubii herba. https://www.ema.europa.eu/en/medicines/herbal/marrubii-herba
  9. Zawiślak G.R.A.Ż.Y.N.A. The chemical composition of the essential oil of Marrubium vulgare L. from Poland. Farmacia. 2012;60:287–292.
  10. Rodríguez Villanueva, J., Martín Esteban, J., & Rodríguez Villanueva, L. (2017). A Reassessment of the Marrubium Vulgare L. Herb’s Potential Role in Diabetes Mellitus Type 2: First Results Guide the Investigation toward New Horizons. Medicines (Basel, Switzerland), 4(3), 57. https://doi.org/10.3390/medicines4030057
  11. Verma A., Masoodi M., Ahmed B. Lead findings from whole plant of Marrubium vulgare L. with hepatoprotective potentials through in silico methods. Asian Pac. J. Trop. Biomed. 2012;2:S1308–S1311. doi: 10.1016/S2221-1691(12)60406-7
  12. El-Leithy A.S., El-Hanafy S.H., Omer E.A., El-Sayed A.A.A. Effect of nitrogen and potassium biofertilization on growth, yield and essential oil production of white horehound, Marrubium vulgare L. Plant. J. Hortic. Sci. Ornam. Plants. 2013;5:46–59. doi: 10.5829/idosi.jhsop.2013.5.1.272
  13. EMA—European Medicines Agency, Committee on Herbal Medicinal Products (HMPC) Community Herbal Monograph on Marrubium vulgare L., herba. HMPC; London, UK: 2013. EMA/HMPC/604271/2012
  14. Amessis-Ouchemoukh N., Abu-Reidah I.M., Quirantes-Piné R., Madani K., Segura-Carretero A. Phytochemical profiling, in vitro evaluation of total phenolic contents and antioxidant properties of Marrubium vulgare (horehound) leaves of plants growing in Algeria. Ind. Crops Prod. 2014;61:120–129. doi: 10.1016/j.indcrop.2014.06.049
  15. Neamah S.I., Sarhan I.A., Al-Shayea O.N. Extraction and evaluation of the anti-inflammatory activity of six compounds of Marrubium vulgare L. Biosci. Res. 2018;15:2393–2400.
  16. Knöss W, Zapp J. Accumulation of furanic labdane diterpenes in Marrubium vulgare and Leonurus cardiaca. Planta Med. 1998 May;64(4):357-61. doi: 10.1055/s-2006-957451
  17. Shaheen F, Rasoola S, Shah ZA, Soomro S, Jabeen A, Mesaik MA, Choudhary MI. Chemical constituents of Marrubium vulgare as potential inhibitors of nitric oxide and respiratory burst. Nat Prod Commun. 2014 Jul;9(7):903-6.
  18. Amri B, Martino E, Vitulo F, Corana F, Kaâb LB, Rui M, Rossi D, Mori M, Rossi S, Collina S. Marrubium vulgare L. Leave Extract: Phytochemical Composition, Antioxidant and Wound Healing Properties. Molecules. 2017 Oct 28;22(11):1851. doi: 10.3390/molecules22111851
  19. Yousefi, K., Hamedeyazdan, S., Torbati, M., & Fathiazad, F. (2016). Chromatographic Fingerprint Analysis of Marrubiin in Marrubium vulgare L. via HPTLC Technique. Advanced pharmaceutical bulletin, 6(1), 131–136. https://doi.org/10.15171/apb.2016.019
  20. Ghedadba N., Hambaba L., Fercha N., Houas B., Abdessemed S., Mokhtar S.M.O. Assessment of hemostatic activity of the aqueous extract of leaves of Marrubium vulgare L., a Mediterranean Lamiaceae Algeria. Int. J. Health Sci. 2016;2:253–258. doi: 10.20319/lijhls.2016.s21.253258
  21. Boudjelal A., Henchiri C., Siracusa L., Sari M., Ruberto G. Compositional analysis and in vivo anti-diabetic activity of wild Algerian Marrubium vulgare L. infusion. Fitoterapia. 2012;83:286–292. doi: 10.1016/j.fitote.2011.11.005
  22. Mittal V., Nanda A. The pharmacognostical evaluation of the Marrubium vulgare Linn collected from the Pulwama district of Jammu and Kashmir State of India. J. Chem. Pharm. Res. 2016;8:7–15.
  23. Salaj N., Barjaktarović J., Kladar N., Gavarić N., Božin B. Biomedical potential of horehound extract (Marrubium vulgare, Lamiaceae) Med. Pregl. 2018;71:21–26. doi: 10.2298/MPNS1802021S
  24. Dallali S., Rouz S., Aichi H., Ben Hassine H. Phenolic content and allelopathic potential of leaves and rizosphere soil aqueous extracts of white horehound (Maribum vulgare L.) J. New Sci. Agric. Biotechnol. 2017;39:2106–2120.
  25. Okur M.E., Karakas N., Karadag A.E., Yilmaz R., Demirci F. In vitro cytotoxicity evaluation of Marrubium vulgare L. methanol extract. J. Res. Pharm. 2019;23:711–718. doi: 10.12991/jrp.2019.180
  26. Gavarić A., Vladić J., Ambrus R., Jokić S., Szabo-Revesz P., Tomić M., Blažić M., Vidović S. Spray drying of a subcritical extract using Marrubium vulgare as a method of choice for obtaining high quality powder. Pharmaceutics. 2019;11:523. doi: 10.3390/pharmaceutics11100523
  27. Yamaguchi, K., Liggett, J. L., Kim, N. C., & Baek, S. J. (2006). Anti-proliferative effect of horehound leaf and wild cherry bark extracts on human colorectal cancer cells. Oncology reports, 15(1), 275–281.
  28. Steinmetz E.F. Materia Medica Vegetabilis. Published by Author; Amsterdam, The Netherlands: 1954.
  29. Bisset N.G. In: Herbal Drugs and Phytopharmaceuticals. Wichtl M., editor. CRC Press; Boca Raton, FL, USA: 2001.
  30. Lodhi S., Vadnere G.P., Sharma V.K., Usman M.R. Marrubium vulgare L.: A review on phytochemical and pharmacological aspects. J. Intercult. Ethnopharmacol. 2017;6:429–452. doi: 10.5455/jice.20170713060840
  31. Akther N., Shawl A., Sultana S., Chandan B., Akhter M. Hepatoprotective activity of Marrubium vulgare against paracetamol induced toxicity. J. Pharm. Res. 2013;7:565–570. doi: 10.1016/j.jopr.2013.06.023
  32. Amri, B., Martino, E., Vitulo, F., Corana, F., Kaâb, L. B., Rui, M., Rossi, D., Mori, M., Rossi, S., & Collina, S. (2017). Marrubium vulgare L. Leave Extract: Phytochemical Composition, Antioxidant and Wound Healing Properties. Molecules (Basel, Switzerland), 22(11), 1851. https://doi.org/10.3390/molecules22111851
  33. Rezgui M., Majdoub N., Ben-Kaab S., Marzouk B., Gouia H., Araujo M.E.M., Ben-Kaab L.B. How salt stress represses the biosynthesis of marrubiin and disturbs the antioxidant activity of Marrubium vulgare L. Pol. J. Environ. Stud. 2017;26:267–277. doi: 10.15244/pjoes/64792
  34. Aouati A., Berchi S. Larvicidal effect of Marrubium vulgare on Culex pipiens in eastern Algeria. Energy Procedia. 2015;74:1026–1031. doi: 10.1016/j.egypro.2015.07.739
  35. Saleh M.M., Glombitza K.W. Volatile oil of Marrubium vulgare and its anti-schistosomal activity. Planta Med. 1989;55:105–106. doi: 10.1055/s-2006-961873
  36. Moussouni L, Benhanifia M, Ayad A. In-vitro Anthelmintic Effects of Aqueous and Ethanolic Extracts of Marrubium vulgare Leaves Against Bovine Digestive Strongyles. Turkiye Parazitol Derg. 2018 Dec;42(4):262-267. doi: 10.5152/tpd.2018.5972
  37. Saidi R., Mimoune N., Baazizi R., Benaissa M.H., Khelef D., Kaidi R. A study of ethno-veterinary medicinal plants and in vitro antimicrobial activities against bovine mastitis isolated bacterial pathogens in Algeria. Bull. UASVM Vet. Med. 2019;76:154–161. doi: 10.15835/buasvmcn-vm:2019.0010
  38. Abdussalam U.S., Aliyu M., Maje I.M. In vivo antiplasmodial activity of ethanol leaf extract of Marrubium vulgare L. (Lamiaceae) in Plasmodium berghei-berghei infected mice. Trop. J. Nat. Prod. Res. 2018;2:132–1135. doi: 10.26538/tjnpr/v2i3.6
  39. Bahadory E.S., Asl A.D., Mosavipoor S.S., Ghaffari A.D., Namroodi S., Novin S.G. The therapeutic effect of Marrubium vulgare, Salvia officinalis and Lippia citrodora in killing of Toxoplasma gondii tachyzoite and evaluation by MTT assay. Med. J. Tabriz Univ. Med. Sci. Health Serv. 2018;39:44–50.
  40. Akbari Z., Dastan D., Maghsood A.H., Fallah M., Matini M. Investigation of in vitro efficacy of Marrubium vulgare L. essential oil and extracts against Trichomonas vaginalis. Zahedan J. Res. Med. Sci. 2018;20:e67003. doi: 10.5812/zjrms.67003
  41. Fayyad A.S.F., Ibrahim N., Yaakob W.A. Phytochemical screening and antiviral activity of Marrubium vulgare. Malays. J. Microbiol. 2014;10:106–111.
  42. Kahlouche-Riachi F., Djerrou Z., Ghoribi L., Djaalab I., Mansour-Djaalab H., Bensari C., Hamdi-Pacha Y. Chemical characterization and antibacterial activity of phases obtained from extracts of Artemisia herba alba, Marrubium vulgare and Pinus pinaster. Int. J. Pharmacogn. Phytochem. Res. 2015;7:270–274.
  43. Kanyonga P.M., Faouzi M.A., Maddah B., Mpona M., Essassi E.M., Cherrah Y. Assessment of methanolic extract of Marrubium vulgare for anti-inflammatory, analgesic and anti-microbiologic activities. J. Chem. Pharm. Res. 2011;3:199–204.
  44. Bouterfas K, Mehdadi Z, Aouad L, Elaoufi MM, Khaled MB, Latreche A, Benchiha W. La localité d’échantillonnage influence-t-elle l’activité antifongique des flavonoïdes de Marrubium vulgare vis-à-vis de Aspergillus niger et Candida albicans ? [Does the sampling locality influence on the antifungal activity of the flavonoids of Marrubium vulgare against Aspergillus niger and Candida albicans?]. J Mycol Med. 2016 Sep;26(3):201-11. French. doi: 10.1016/j.mycmed.2016.02.019
  45. Rezgui M, Majdoub N, Mabrouk B, Baldisserotto A, Bino A, Ben Kaab LB, Manfredini S. Antioxidant and antifungal activities of marrubiin, extracts and essential oil from Marrubium vulgare L. against pathogenic dermatophyte strains. J Mycol Med. 2020 Apr;30(1):100927. doi: 10.1016/j.mycmed.2020.100927
  46. Zarai, Z., Kadri, A., Ben Chobba, I., Ben Mansour, R., Bekir, A., Mejdoub, H., & Gharsallah, N. (2011). The in-vitro evaluation of antibacterial, antifungal and cytotoxic properties of Marrubium vulgare L. essential oil grown in Tunisia. Lipids in health and disease, 10, 161. https://doi.org/10.1186/1476-511X-10-161
  47. Oliveira A.P., Santin J.R., Lemos M., Junior L.C.K., Couto A.G., Bittencourt C.M.S., Filho V.C., Andrade S.F. Gastroprotective activity of methanol extract and marrubiin obtained from leaves of Marrubium vulgare L. (Lamiaceae) J. Pharm. Pharmacol. 2011;63:1230–1237. doi: 10.1111/j.2042-7158.2011.01321.x
  48. El Bardai S.E., Morel N., Wibo M., Fabre N., Llabres G., Lyoussi B., Quetin-Leclercq I. The vasorelaxant activity of marrubenol and marrubiin from Marrubium vulgare. Planta Med. 2003;69:75–77. doi: 10.1055/s-2003-37042
  49. El Bardai S., Wibo M., Hamaide M.C., Lyoussi B., Quetin-Leclercq J., Morel N. Characterisation of marubenol, a diterpene extracted from Marrubium vulgare, as an L-type calcium channel blocker. Br. J. Pharmacol. 2003;140:1211–1216. doi: 10.1038/sj.bjp.0705561
  50. El Bardai S, Lyoussi B, Wibo M, Morel N. Comparative study of the antihypertensive activity of Marrubium vulgare and of the dihydropyridine calcium antagonist amlodipine in spontaneously hypertensive rat. Clin Exp Hypertens. 2004 Aug;26(6):465-74. doi: 10.1081/ceh-200031818
  51. Barkaoui M, Katiri A, Boubaker H, Msanda F. Ethnobotanical survey of medicinal plants used in the traditional treatment of diabetes in Chtouka Ait Baha and Tiznit (Western Anti-Atlas), Morocco. J Ethnopharmacol. 2017 Feb 23;198:338-350. doi: 10.1016/j.jep.2017.01.023
  52. Hellal, K., Maulidiani, M., Ismail, I. S., Tan, C. P., & Abas, F. (2020). Antioxidant, α-Glucosidase, and Nitric Oxide Inhibitory Activities of Six Algerian Traditional Medicinal Plant Extracts and 1H-NMR-Based Metabolomics Study of the Active Extract. Molecules (Basel, Switzerland), 25(5), 1247. https://doi.org/10.3390/molecules25051247
  53. Chakir A.R.S., Elbadaoui K., Alaoui T. Antidiabetic activities of methanolic extracts of Marrubium vulgare leaves in rats. Int. J. Pharm. Phytopharm. Res. 2015;4:258–263.
  54. Elmhdwi M.F. Hypoglycemic effects of Marrubium vulgare (Rubia) in experimentally induced autoimmune diabetes mellitus. Int. Res. J. Biochem. Bioinform. 2014;44:42–54.
  55. Alkofahi AS, Abdul-Razzak KK, Alzoubi KH, Khabour OF. Report – Screening of the Anti-hyperglycemic activity of some medicinal plants of Jordan. Pak J Pharm Sci. 2017 May;30(3):907-912.
  56. Dehkordi F.R., Roghani M., Baluchnejadmojarad T. The effect of Marrubium vulgare on contractile reactivity of aorta in diabetic rats. ARYA Atheroscler. J. 2012;7:1–4.
  57. Herrera-Arellano A, Aguilar-Santamaría L, García-Hernández B, Nicasio-Torres P, Tortoriello J. Clinical trial of Cecropia obtusifolia and Marrubium vulgare leaf extracts on blood glucose and serum lipids in type 2 diabetics. Phytomedicine. 2004 Nov;11(7-8):561-6. doi: 10.1016/j.phymed.2004.01.006
  58. Ibrahim AY, Hendawy SF, Elsayed AA, Omer EA. Evaluation of hypolipidemic Marrubium vulgare effect in Triton WR-1339-induced hyperlipidemia in mice. Asian Pac J Trop Med. 2016 May;9(5):453-9. doi: 10.1016/j.apjtm.2016.03.038
  59. Hamza N, Berke B, Umar A, Cheze C, Gin H, Moore N. A review of Algerian medicinal plants used in the treatment of diabetes. J Ethnopharmacol. 2019 Jun 28;238:111841. doi: 10.1016/j.jep.2019.111841
  60. Sirtori CR, Pavanello C, Calabresi L, Ruscica M. Nutraceutical approaches to metabolic syndrome. Ann Med. 2017 Dec;49(8):678-697. doi: 10.1080/07853890.2017.1366042
  61. Hosseinzadeh H., Ziaee T., Ahi A. Effect of Marrubium vulgare L. aerial parts aqueous and ethanolic extracts on morphine withdrawal syndrome in mice. Pharmacologyonline. 2007;3:422–427.
  62. Ajedi A.S.S., Widodo N., Widyarti S., Rifai M. Immunomodulatory effect of Moringa oleifera and Marrubium vulgare leaf aqueous extracts in BALB/C mice infected with Salmonella typhimurium; Proceedings of the 144th the IRES International Conference; Bali, Indonesia. 30–31 October 2018.
  63. Yousefi K, Fathiazad F, Soraya H, Rameshrad M, Maleki-Dizaji N, Garjani A. Marrubium vulgare L. methanolic extract inhibits inflammatory response and prevents cardiomyocyte fibrosis in isoproterenol-induced acute myocardial infarction in rats. Bioimpacts. 2014;4(1):21-7. doi: 10.5681/bi.2014.001
  64. Sahpaz S., Garbacki N., Tits M., Bailleul F. Isolation and pharmacological activity of phenylpropanoid esters from Marrubium vulgare. J. Ethnopharmacol. 2002;79:389–392. doi: 10.1016/S0378-8741(01)00415-9
  65. Ghedadba N., Hambaba L., Bousselsela H., Hachemi M., Drid A., Abd-Essmad A., Oueld-Mokhtar S.M. Evaluation of in vitro antioxidant and in vivo anti-inflammatory potential of white horehound (Marrubium vulgare L.) leaves. Int. J. Pharm. Sci. Rev. Res. 2016;41:252–259.
  66. Stulzer H.K., Tagliari M.P., Zampirolo J.A., Cechinel-Filho V., Schlemper V. Antioedematogenic effect of marrubiin obtained from Marrubium vulgare. J. Ethnopharmacol. 2006;108:379–384. doi: 10.1016/j.jep.2006.05.023
  67. Bourhia, M., Abdelaziz Shahat, A., Mohammed Almarfadi, O., Ali Naser, F., Mostafa Abdelmageed, W., Ait Haj Said, A., El Gueddari, F., Naamane, A., Benbacer, L., & Khlil, N. (2019). Ethnopharmacological Survey of Herbal Remedies Used for the Treatment of Cancer in the Greater Casablanca-Morocco. Evidence-based complementary and alternative medicine : eCAM, 2019, 1613457. https://doi.org/10.1155/2019/1613457
  68. Paunovic V, Kosic M, Djordjevic S, Zugic A, Djalinac N, Gasic U, Trajkovic V, Harhaji-Trajkovic J. Marrubium vulgare ethanolic extract induces proliferation block, apoptosis, and cytoprotective autophagy in cancer cells in vitro. Cell Mol Biol (Noisy-le-grand). 2016 Sep 30;62(11):108-114.
  69. Nawal H.M., Atta E.M. Cytotoxic and antioxidant activity of Marrubium vulgare and flavonoid constituents; Proceedings of the 2nd International Conference on Chemical, Environmental and Biological Sciences; Dubai, UAE. 17–18 March 2013.
  70. Alkhatib R., Joha S., Cheok M., Roumiy V., Idziorek T., Preudhomme C., Quesnel B., Sahpaz S., Bailleul F., Hennebelle T. Activity of ladanein on leukemia cell lines and its occurrence in Marrubium vulgare. Planta Med. 2010;76:86–87. doi: 10.1055/s-0029-1185972
  71. Tlili, H., Hanen, N., Ben Arfa, A., Neffati, M., Boubakri, A., Buonocore, D., Dossena, M., Verri, M., & Doria, E. (2019). Biochemical profile and in vitro biological activities of extracts from seven folk medicinal plants growing wild in southern Tunisia. PloS one, 14(9), e0213049. https://doi.org/10.1371/journal.pone.0213049
  72. Kozyra, M., Korga, A., Ostrowska, M., Humeniuk, E., Adamczuk, G., Gieroba, R., Makuch-Kocka, A., & Dudka, J. (2020). Cytotoxic activity of methanolic fractions of different Marrubium spp. against melanoma cells is independent of antioxidant activity and total phenolic content. FEBS open bio, 10(1), 86–95. https://doi.org/10.1002/2211-5463.12755
  73. Shawky E. Prediction of potential cancer-related molecular targets of North African plants constituents using network pharmacology-based analysis. J Ethnopharmacol. 2019 Jun 28;238:111826. doi: 10.1016/j.jep.2019.111826
  74. Ibrahim F.M., Ibrahim A.Y., Omer E.A. Potential effect of Marrubium vulgare L. extracts on CCl4 model induced hepatotoxicity in albino mice. World J. Pharm. Sci. 2014;2:1664–1670.
  75. El-Hallous E.I., Alsanie W.F., Ismail I.A., Dessoky E.S. Utilization of Marrubium vulgare extract as a therapeutic to hepatic damage induced by carbon tetrachloride in rats. Int. J. Pharm. Res. Allied Sci. 2018;7:168–178.
  76. Elberry AA, Harraz FM, Ghareib SA, Nagy AA, Gabr SA, Suliaman MI, Abdel-Sattar E. Antihepatotoxic effect of marrubium vulgare and withania somnifera extracts on carbon tetrachloride-induced hepatotoxicity in rats. J Basic Clin Pharm. 2010 Sep;1(4):247-54.
  77. Ahmed B, Masoodi MH, Siddique AH, Khan S. A new monoterpene acid from Marrubium vulgare with potential antihepatotoxic activity. Nat Prod Res. 2010 Nov;24(18):1671-80. doi: 10.1080/14786410802280976
  78. Mbah C.J., Orabueze I., Okorie N.H. Antioxidants properties of natural and synthetic chemical compounds: Therapeutic effects on biological system. Acta Sci. Pharm. Sci. 2019;3:28–42. doi: 10.31080/ASPS.2019.03.0273
  79. Abadi A., Hassani A. Essential oil composition and antioxidant activity of Marrubium vulgare L. growing wild in Eastern Algeria. Int. Lett. Chem. Phys. Astron. 2013;9:17–24. doi: 10.18052/www.scipress.com/ILCPA.14.17
  80. Djeridane A, Yousfi M, Brunel JM, Stocker P. Isolation and characterization of a new steroid derivative as a powerful antioxidant from Cleome arabica in screening the in vitro antioxidant capacity of 18 Algerian medicinal plants. Food Chem Toxicol. 2010 Oct;48(10):2599-606. doi: 10.1016/j.fct.2010.06.028. Epub 2010 Jun 22. Retraction in: Food Chem Toxicol. 2017 Mar;101:168. [Retracted article]
  81. Weel K.G.C., Venskutonis P.R., Pukalskas A., Gruzdiene D., Linssen J.P.H. Antioxidant activity of horehound (Marrubium vulgare L.) grown in Lithuania. Lipid. 1999;101:395–400. doi: 10.1002/(SICI)1521-4133(199910)101:10<395::AID-LIPI395>3.0.CO;2-L
  82. Bouterfas K, Mehdadi Z, Elaoufi MM, Latreche A, Benchiha W. Antioxidant activity and total phenolic and flavonoids content variations of leaves extracts of white Horehound (Marrubium vulgare Linné) from three geographical origins. Ann Pharm Fr. 2016 Nov;74(6):453-462. doi: 10.1016/j.pharma.2016.07.002
  83. Aouni R, Ben Attia M, Jaafoura MH, Bibi-Derbel A, Haouari M. Effects of the hydro-ethanolic extract of Marrubium vulgare in female rats. Asian Pac J Trop Med. 2017 Feb;10(2):160-164. doi: 10.1016/j.apjtm.2017.01.010
  84. Mokhtari M., Ebrahimpoor M.R., Harfsheno S. The effects of alcoholic extract of Marrubum vulgare on hormonal parameters in female rat model of polycystic ovarian syndrome. Med. Sci. 2014;24:74–80.
  85. Kolangi F, Memariani Z, Bozorgi M, Mozaffarpur SA, Mirzapour M. Herbs with Potential Nephrotoxic Effects According to the Traditional Persian Medicine: Review and Assessment of Scientific Evidence. Curr Drug Metab. 2018;19(7):628-637. doi: 10.2174/1389200219666180404095849
  86. Al-Snafi A.E. The Pharmacological Importance of Ballota nigra—A review. Ind. J. Pharm. Sci. Res. 2015;5:249–256.
  87. Nusier MK, Bataineh HN, Bataineh ZM, Daradka HM. Effects of Ballota nigra on glucose and insulin in alloxan-diabetic albino rats. Neuro Endocrinol Lett. 2007 Aug;28(4):470-2.
  88. Ullah, N., Ahmad, I., & Ayaz, S. (2014). In vitro antimicrobial and antiprotozoal activities, phytochemical screening and heavy metals toxicity of different parts of Ballota nigra. BioMed research international, 2014, 321803. https://doi.org/10.1155/2014/321803
  89. Kováts, N., Ács, A., Gölöncsér, F., & Barabás, A. (2011). Quantifying of bactericide properties of medicinal plants. Plant signaling & behavior, 6(6), 777–779. https://doi.org/10.4161/psb.6.6.15356
  90. Di Sanzo, P., De Martino, L., Mancini, E., & Feo, V. D. (2013). Medicinal and useful plants in the tradition of Rotonda, Pollino National Park, Southern Italy. Journal of ethnobiology and ethnomedicine, 9, 19. https://doi.org/10.1186/1746-4269-9-19
Health Jade Team 3

The author Health Jade Team 3

Health Jade