Teucrium polium (Teucrium polium L.; English name: Felty Germander) is a perennial wild flowering plant widely distributed in North Africa, Europe, and South-Western Asia.
It is a plant belonging to the
Lamiaceae family, and is used in folk medicine. In terms of plant morphology, it is an herbaceous plant with many branches at heights of 10 to 35 cm and has a white cotton appearance. The branches of this plant are round and often seen in reddish-purple color. The flowers of
T. polium are relatively large, and are arranged in clusters of one to six in the upper leaf axis and are white, yellowish white, yellow or even purple in color (
Figure 1).
This plant is mainly found in barren areas, rocky beaches, and sand fields. Regarding geographical distribution,
T. polium has a pluriregional distribution and grows in Europe, Asia, North Africa, and some parts of Asia. In Iran, it is widely distributed in different regions of the north, south, west, and center. Due to the diverse geographical distribution and availability of this plant, this plant in many regions, including Iran, Turkey, and parts of Europe is used to treat various diseases (
18-
20). In terms of the history of plant consumption, based on the available documents, the history of using this plant dates back to more than two thousand years and to Hippocrates and Galen time (
21,
22). Also, the existence of valuable sources and documents of Iranian medicine from scientists, such as Abolhassan Ali Ibn Abbas Ahvazi, Ibn Sina, Ismaeil Ibn Hussein Jorjani, Mohammad Zakaria Razi, and Mohammad Hossein Aghili Alavi Khorasani Shirazi, suggests the continuous use of herbal medicines to treat diseases over the centuries (
21-
23). This plant, with the name Jaadeh in some sources ofIranian traditional medicine, has a warm and dry temperament, and according to some people, it has a dry temperament. Some of the plant functions in the body include antidote, laxative, diuretic, and menstruation and is used to clean the uterus, help to treat dysuria and joint pains (
24). Although
T. polium is one of the herbal medicines traditionally used to treat some diseases, new studies on this plant indicate its useful effects in treating many disorders. Twaij et al. investigated the effect of 150 mg/kg aqueous extract of
T. polium by intraperitoneal injection (
25). The results showed that it caused 50% recovery in gastrointestinal ulcers induced by reserpine 20 mg/kg, while receiving the same amount of extract orally resulted in recovery in 85% of gastrointestinal ulcers (
25). Moreover, a study by Gharib Naseri and Omidi Birgani on aqueous extract of
T. polium in 2007 showed that it has antispasmodic effects on ilium contractions in rats induced by potassium chloride (
26).
A study conducted by Shahraki et al. on rats in 2006 showed that visceral analgesic effect in the group receiving the aqueous extract of
T. polium orally for 30 days at a dose of 50 mg/kg compared with the group receiving subcutaneous morphine sulfate at a dose of 10 mg/kg for 4 days was not significantly different, although the tail response to the analgesic stimulus was significantly different in both groups compared with the control group (
27). Another study conducted by Abdollahi et al. confirmed the analgesic effects of aqueous extract of
T. polium at 150, 225, and 300 mg/kg doses (
28). The essential oil of the plant significantly reduced the writing test response compared with the control group. These effects are probably due to flavonoids and sterols that have anti-inflammatory effects (
28). The antioxidant effects of the plant at doses of 50 and 100 mg/kg in in vitro studies are equivalent to 10 mg/kg α-tocopherol (
29).
Teucrium polium is among the fragrant plants and contains tannin, terpenoid, saponin, flavonoid, glycoside-α, sterol, leucoanthocyanin, beta-caryophyllene, caryophyllene oxide, diterpenoid, asparagine, and dietrin, and some of these compounds have inflammation effects (
30-
32).
The presence of flavonoids and sterols may be responsible for the anti-inflammatory activity of this medicinal plant.
Teucrium polium also applies anti-cancer effect through mitochondrial changes, and these results are due to increased activity of Sirt3 in the HT-29 colorectal cancer cell line (
33). A study conducted by Emami Zeydi showed that the metabolic extract of
T. Polium enhances the cytotoxic and apoptotic effects in vincristine, vinblastine, and doxorubicin drugs against cancer cells, indicating that the metabolic extract of
T. polium can be an effective factor of chemotherapy for treatment of cancer (
34). This plant can be used as a natural remedy for managing cardiovascular diseases. A study conducted by Amraei et al. showed that receiving 170 mg/kg of the hydroalcoholic extract of
T. polium reduces serum levels of triglycerides, LDL-cholesterol, and cholesterol and increases serum levels of HDL-cholesterol (
35). In a triple-blind study conducted on 70 women aged 20 to 30, results showed that oral administration of 250 mg of
T. polium capsules every 6 hours during the first three days of menstruation resulted in a significant reduction in bleeding during menstruation (
36). It has been shown that
T. polium increases breast milk and reduces patients’ complaints of digestive problems in the last months of pregnancy and after delivery (
37). Given the presence of biologically active compounds in
T. polium, this plant seems to have significant antimicrobial effects (
38). The ethanolic extract of
T. polium in vitro has shown significant antimicrobial activity against
Pseudomonas aeruginosa and
Escherichia coli as Gram-negative bacteria and
Streptococcus pyogenes,
Staphylococcus epidermidis, and
Staphylococcus aureus as Gram-positive bacteria (
39). The flowers of this plant contain volatile essential oils, picrosalvin, saponin, cineole, diterpene, and camphor (
40).
It has also been shown that
T. polium extract has significant antioxidant activity in the body and antioxidant activity of
T. polium extract is similar to that of α tocopherol antioxidant (
29,
36). Ljubuncic et al. also showed that
T. polium extract can inhibit oxidative processes thanks to its antioxidant activity (
41). Antioxidant effects can play an effective role in reducing and curing inflammatory diseases (
42). Common vaginitis in women is caused by microorganisms, such as
Candida albicans (fungi),
Haemophilus vaginalis, and
T. vaginalis parasite (
43). In a study conducted by Fazeli Nasab et al., results showed that
T. polium has strong antioxidant properties due to its phenol and flavonoids so that after
Myrtus and
Rosemary extracts, the hydroalcoholic extract of
T. polium has the highest antioxidant properties and consequently antimicrobial properties (
44). A study conducted by Bahmani et al. showed that the plants of
Lamiaceae family, including
T. polium, that contain compounds such as diterpenoids, 5-7-glycoside, thymols, carvacrols, and volatile essential oils in the northwestern regions of Iran are widely used to treat infections (
23). Khoramian Tusi et al. showed that
T. polium mouthwash can reduce the number of salivary
Streptococcus mutans (
45). A study conducted by Qabaha found that
T. polium extract has extended antimicrobial activity against eight species of clinical pathogens and significant antioxidant ability (
46). Bonyayeian Boroujani showed that
T. polium extract inhibits the growth of
C. albicans and may be effective in treating vaginitis caused by this fungus (
16).
The results of a study done by Moghtader et al. showed that
T. polium essential oil has a high inhibitory and antimicrobial power (
40). The antibacterial effects of
T. polium essential oil can be attributed to the compounds of α-pinene and linalool (the plant’s major compounds). They showed good antibacterial effects against three Gram-positive bacteria, including
S. aureus,
S. epidermidis, and
Streptococcus faecalis, and 6 Gram-negative bacteria of
P. aeruginosa,
Shigella flexneri,
Klebsiella pneumoniae,
Salmonella latifii,
Serratia marcescens, and
E. coli (
40). In a phytochemical study of
T. polium plant, Bahramikia and Yazdanparast showed that the extract and components isolated from different parts of this plant have special biological effects, and
T. polium has different properties such as antioxidant, antiseptic, anti-inflammatory, cytotoxic, antibacterial and antifungal properties (
47). Antioxidant, antiseptic, and anti-free radical activities have been proven by in vitro methods in many studies on the
T. polium plant using in vitro models (
47). Bezić et al. showed that the combination of sesquiterpenes and beta-caryophyllene, as the main component of
T. polium oil, is effective as an anti-phytoviral responsible for antiviral activity in this plant. However, some other components may contribute to its effectiveness (
48). Talib and Mahasneh showed that other species of the genus Teucrium, such as
Teucrium chamaedrys, have antibacterial activity against
P. aeruginosa,
Salmonella,
E. coli,
Bacillus cereus, and antifungal activity against
C. albicans and
Aspergillus niger (
49). The results of the study conducted by Bonyadpour et al. showed that the use of other methods of consumption of
T. polium (plant smoke) also has suitable antifungal effects in comparison with clotrimazole and fluconazole azoles (
50).
Essawi and Srour found that the extract of this plant showed a wide range of activities against both Gram-positive and Gram-negative bacteria and confirmed the use of this plant in traditional medicine to treat infections (
51). Also, a survey carried out by Amirrajab et al. showed that the hydroethanolic extracts of
T. polium leaf revealed moderate anti-candidial effectiveness (
52).
Results of several studies on the phytochemical, medicinal and antifungal, antibacterial, antibiotic, and antioxidant effects of
T. polium and its effectiveness in treating many diseases and infections indicate that it has useful and effective therapeutic properties against microorganisms and treatment of infections. Since the common causes of vaginitis are bacteria, fungi, and other infectious microorganisms, the potential anti-inflammatory, antifungal, antibacterial, and antibiotic effects of
T. polium can be used in vaginal infection treatment. Despite the positive effects of this plant, the use of herbal medicines containing
T. polium extract without any scientific guidance in some cases has led to liver toxicity, which is due to increased blood urea and cholesterol after receiving its hydroalcoholic extract for six weeks at doses of 50 mg/kg and 20 mg (
20,
53,
54).