Chemical Constituents of Plants from the Genus Dracocephalum

The effect of Dracocephalum subcapitatum hydroalcoholic extract on dexamethasone-induced hyperlipidemic rats

Background and purpose

Recent data show the antihyperlipidemic activities of some plants belonging to the genus Dracocephalum. In this study, the effects of hydroalcoholic extract of D. subcapitatum (O. Kuntze) Lipsky aerial parts were evaluated in a model of hyperlipidemia induced by dexamethasone.

Experimental approach

The extract was prepared by maceration method and its total phenolic content was determined. Seven groups of 6 Wistar rats were used as follows: group 1 (normal control) received vehicle; group 2 (extract control) treated only with 200 mg/kg D. subcapitatum; group 3 (hyperlipidemia control) received dexamethasone (10 mg/kg/day, subcutaneously); group 4 (reference) received dexamethasone and atorvastatin (40 mg/kg, orally), and groups 5-7 (test groups) received dexamethasone and simultaneously treated orally with 50, 100, or 200 mg/kg D. subcapitatum. All treatments were done for 1 week. Serum lipid profile, fasting blood glucose, malondialdehyde concentration, and liver histopathology were examined.

Findings/Results

Total phenolic content was 77.34 ± 4.9 mg/g as gallic acid equivalent. Treatment with D. subcapitatum (200 mg/kg) meaningfully declined triglycerides, total cholesterol, low-density lipoprotein, very low-density lipoprotein, blood glucose, alanine aminotransferase, aspartate aminotransferase, and malondialdehyde levels, and alleviated hepatic steatosis in dexamethasone-induced dyslipidemic rats.

Conclusion and implications

Findings of the current study suggest that D. subcapitatum may be effective in the management of hyperlipidemia. Further studies are necessary to determine the clinical efficacy of this treatment and to understand the underlying mechanisms responsible for its ability to lower lipid levels.

Medium- and High-Pressure Integrated Chromatographic Strategies for the Isolation and Purification of Free Radical Inhibitors from Dracocephalum heterophyllum

Dracocephalum heterophyllum has been reported as a traditional Tibetan medicine with diverse therapeutic benefits for the effective treatment of various diseases. However, only a few reports on its free radical inhibitors are limited due to its complex chemical composition and difficult isolation and purification processes. In this study, five free radical inhibitors are isolated by an integrated chromatographic method from Dracocephalum heterophyllum, followed by an investigation of the in vitro antioxidant activity utilizing 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Medium-pressure liquid chromatography was used for the pretreatment of the crude extract of Dracocephalum heterophyllum and targeted separation and purification of the free radical inhibitors using high-pressure liquid chromatography; the antioxidant peaks are recognized by the separation and purification process in combination with an online HPLC-DPPH system. Five free radical inhibitors with purity higher than 95% were obtained, namely xanthotoxol, 5-hydroxy-8-methoxypsoralen, luteolin, methyl rosmarinate, and ethyl rosmarinate. Finally, DPPH assays are performed, and their IC50 values for isolated compounds are 250.39 ± 13.32 μM, 26.91 ± 1.93 μM, 66.87 ± 14.33 μM, 21.99 ± 3.17 μM, and 36.96 ± 1.72 μM, respectively. This method is effective in isolating free radical inhibitors from Dracocephalum heterophyllum, and it has the potential to be adopted for the isolation of antioxidants from other plants of medicinal value as well.

Flavones, Flavonols, Lignans, and Caffeic Acid Derivatives from Dracocephalum moldavica and Their In Vitro Effects on Multiple Myeloma and Acute Myeloid Leukemia

Phenolic plant constituents are well known for their health-promoting and cancer chemopreventive properties, and products containing such constituents are therefore readily consumed. In the present work, we isolated 13 phenolic constituents of four different compound classes from the aerial parts of the Moldavian dragonhead, an aromatic and medicinal plant with a high diversity on secondary metabolites. All compounds were tested for their apoptotic effect on myeloma (KMS-12-PE) and AML (Molm-13) cells, with the highest activity observed for the flavone and flavonol derivatives. While diosmetin (6) exhibited the most pronounced effects on the myeloma cell line, two polymethylated flavones, namely cirsimaritin (1) and xanthomicrol (3), were particularly active against AML cells and therefore subsequently investigated for their antiproliferative effects at lower concentrations. At a concentration of 2.5 µM, cirsimaritin (1) reduced proliferation of Molm-13 cells by 72% while xanthomicrol (3) even inhibited proliferation to the extent of 84% of control. In addition, both compounds were identified as potent FLT3 inhibitors and thus display promising lead structures for further drug development. Moreover, our results confirmed the chemopreventive properties of flavonoids in general, and in particular of polymethylated flavones, which have been intensively investigated especially over the last decade.

Dracocephalum kotschyi Boiss. In Vitro Efficacy on Growth and Apoptosis Induction in Leishmania major Promastigotes

Dracocephalum kotschyi Boiss. is a plant generally used in modern medicine to treat many human illnesses. It is also used to prevent tumor cell proliferation throughout the world. This study's objective was to evaluate this plant's in vitro efficacy on growth and apoptosis induction in Leishmania major promastigotes. To do this, the essential oil is extracted for the test following the collection and identification of D. kotschyi. The essential oil was analyzed using a GC-MS analyzer. Promastigotes of L. major were cultured in RPMI-1640 media, and the MTT assay and a flow cytometry analysis were carried out on promastigotes that had entered the log phase. To differentiate between viable, necrotic, and apoptotic treated or untreated promastigotes, the flow cytometry method of double staining with annexin V-FLUOS and propidium iodide (PI) was used. Given the results obtained, 11 phytochemicals were identified in the essential oil of this plant. Copaene (22.15%), methyl geranate (16.31%), geranial (13.78%), and carvone (11.34%) were the main substances. The essential oil of D. kotschyi inhibits the proliferation of L. major promastigotes at 921 μg/mL, 252 μg/mL, and 416 μg/mL, respectively, after 24 h, 48 h, and 78 h. The cells were divided into four quadrates based on cell phases using the flow cytometry approach by double staining with annexin V-FLUOS and propidium iodide (PI): necrosis (Q1), late apoptosis (Q2), early apoptosis (Q3), and viable (Q4) quadrates. Overall, it is apparent that the different concentrations induced cell apoptosis in promastigotes. Observation under the light microscope at ×100 magnification showed that the different doses of D. kotschyi essential oil caused apparent alterations in the treated promastigotes. In this work, D. kotschyi essential oils induce programmed death on L. major promastigotes. This study opens many research perspectives, such as investigating the mechanisms of action and the production of a phytomedicine based on this plant.

A GC-MC analysis of chemical compounds and identification of the antibacterial characteristics of the essential oil of two species exclusive to Iranian habitats: New chemotypes

BACKGROUND

The diversity found in the chemical compounds of a single species in different regions results in different biologic characteristics which can be considered as a strong source for identifying new chemotypes. Hymenocrater incanus Bunge and Dracocephalum kotschyi Boiss. are exclusive species of the Lamiaceae family which grow in the western and central habitats of Iran. This study was designed and carried out to determine the yield, identify the chemical compounds, and evaluate the antimicrobial characteristics of the essential oil (EO) of these two species in Iran for the first time.

METHODS

The flowering twigs of the species D. kotschyi and H. incanus were collected from the villages of Totmach and Kamu in Isfahan province respectively, in May 2019. The EO of these plants was extracted and separated using the water distillation method, utilizing the Clevenger device. The EO compounds were analyzed using a gas chromatograph coupled with a mass spectrometer (GC-MS). The evaluation of antimicrobial characteristics was carried out by determining the growth inhibition zone implementing the Agar method, the minimum inhibition concentration (MIC), and the minimum bactericidal/fungicidal concentration (MFC/MBC) utilizing liquid dilution culture.

RESULTS

The results indicated that the highest yield belonged to the EO of D. kotschyi at %2.6 (w/w). In this EO there were citral (%25.44), neral (%20.87), α-pinene (%14.48), trans-geranic acid methyl ester (%9.74), and D-limonene (%6.87). Moreover, H. incanus had the dominant compounds (-)-Spathulenol (%12.61), caryophyllene (%10.00), linolenic acid (%8.54), 1,8-cineole (%5.95), palmitic acid (%5.35), and α-cadinol (%5.17). The largest diameter of growth inhibition zone belonged to the H. incanus EO against the Gram-positive bacteria S. pyogenes (~17.67mm). The strongest inhibition activities in the form of growth inhibition diameter exhibited by the D. kotschyi EO were against the Gram-negative bacteria S. paratyphi-A serotype (~ 12 mm), K. pneumoniae, and Sh. dysenteriae (~ 11 mm) which was significant compared to the Gram-positive rifampin (~ 8 mm).

CONCLUSIONS

It can be seen that these species are new chemotypes with special and novel chemical compounds which can potentially be used to manufacture natural antibiotics against some bacterial strains.

Caucasian Dragonheads: Phenolic Compounds, Polysaccharides, and Bioactivity of Dracocephalum austriacum and Dracocephalum botryoides

Dracocephalum botryoides Steven and Dracocephalum austriacum L. are unexplored species of the Dracocephalum genus (Lamiaceae family) with a distribution in the Caucasus, where they are used in folk medicine and local cuisine. There are no data on the chemical composition of these Dracocephalum species. In this study, the application of a liquid chromatography-mass spectrometry technique for the metabolite profiling of methanol extracts from herbs and roots of D. austriacum and D. botryoides resulted in the identification of 50 compounds, including benzoic acid derivatives, phenylpropanoids, flavonoids and lignans. Water-soluble polysaccharides of the herbs and roots of D. austriacum and D. botryoides were isolated and characterized as mostly pectins with additive arabinogalactan-protein complexes and starch-like compounds. The antioxidant potential of the studied extracts of Dracocephalum and selected phenolics and water-soluble polysaccharides were investigated via radical-scavenging and ferrous (II) ion chelating assays. This paper demonstrates that herbs and roots of D. austriacum and D. botryoides are rich sources of metabolites and could be valuable plants for new biologically active products. To the best of our knowledge, this is the first study of whole plant metabolites and their antioxidant activity in D. austriacum and D. botryoides.

Preparation and Antioxidant Activities of Phenylethanoids from Dracocephalum heterophyllum

The health benefits of Dracocephalum heterophyllum are widely reported in traditional Tibetan medicines, but the reported chemical composition is limited, probably due to difficulties in separating and purifying compounds. In this study, antioxidative phenylethanoids were isolated from an extract of Dracocephalum heterophyllum using medium- and high-pressure liquid chromatography, coupled with on-line HPLC–1,1-diphenyl-2-picrylhydrazyl recognition. Firstly, crude samples (1.3 kg) of Dracocephalum heterophyllum were pretreated via silica gel medium-pressure liquid chromatography to yield 994.0 g of Fr2, of which 10.8 g was then pretreated via MCI GEL®CHP20P medium-pressure liquid chromatography. The resulting Fr23 and Fr25 were further separated and purified using high-pressure liquid chromatography, and yielded 8.08 mg of Fr2391, 9.76 mg of Fr2551, 16.09 mg of Fr2581, and 8.75 mg of Fr2582. Furthermore, analysis of the purity and structures of the phenylethanoids suggested that Fr2391, Fr2551, Fr2581, and Fr2582 corresponded to decaffeoylverbascoside, rosmarinic acid, acteoside, and 2′-O-acetylplantamajoside, respectively, with all being over 95% pure. Finally, the antioxidant potential of the compounds was explored based on their ability to scavenge 1,1-diphenyl-2-picrylhydrazine, as well as through molecular docking of proteins related to antioxidant pathways. Altogether, our findings revealed that the proposed method is promising for separating pure antioxidative phenylethanoids from other natural compounds.

In Vitro and In Vivo Anti-Toxoplasma Activities of Dracocephalum kotschyi Extract in Experimental Models of Acute Toxoplasmosis

BACKGROUND

The problem of resistance to antiparasitic drugs, associated with their side effects, suggest exploring other alternatives, including medicinal plants. Dracocephalum kotschyi (D. kotschyi), for example, from Lamiaceae family, is a plant widely used in Iran and in many countries, and to which interesting pharmacological properties have been attributed. This study aimed to investigate in vitro and in vivo anti-Toxoplasma activities of D. kotschyi extract in experimental models of acute toxoplasmosis.

METHODS

Anti-Toxoplasma activity of the extracts in vitro was performed on Vero Cell, using the MTT test. Vero cell were infected with (3 × 10⁵ tachyzoites/well) following treatment with Dichloromethane (F1), dichloromethane: methanol (F2), methanol (F3), methanol: water (F4), and deionized water (F5) extracts of D. kotschyi, and pyrimethamine and sulfadiazine (positive control). MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) was used to measure cell viability. Effects of extracts on tachyzoites viability were evaluated by trypan blue exclusion method, followed by light microscopy. For in vivo test, 18 groups of 8-10-week-old Inbred Balb/c mice weighing 18-20 g, were intraperitoneally infected with 2 × 10³ tachyzoites and then treated with sterile PBS (negative control), pyrimethamine (25 mg/kg) and sulfadiazine (500 mg/kg) as positive controls, and F1 to F5 extracts (at doses 50, 100 and 200 mg/kg).

RESULTS

The 50% Inhibitory Concentration of F1 extract, F2 extract, Sulfadiazine (Positive control) and Pyrimethamine (Positive control) were 8.77 µg, 7.1 µg 391.18 µg, and 84.20 µg, respectively, while the selectivity indices were 15.667, 30.197, 1.552 and 4.064, respectively. In vivo anti-Toxoplasma activity test showed that Methanol: water (F-4) 50 extract was more active than the positive control.

CONCLUSIONS

Indeed, the extract allowed a survival rate of 10% of the mice, compared to 0% for all the other groups. D. kotschyi has the potential to be valorized in the management of toxoplasmosis.

Dracocephalum palmatum S. and Dracocephalum ruyschiana L. Originating from Yakutia: A High-Resolution Mass Spectrometric Approach for the Comprehensive Characterization of Phenolic Compounds

Dracocephalum palmatum S. and Dracocephalum ruyschiana L. contain a large number of target analytes, which are biologically active compounds. High performance liquid chromatography (HPLC) in combination with an ion trap (tandem mass spectrometry) was used to identify target analytes in extracts of D. palmatum S. and D. ruyschiana L. originating from Yakutia. The results of initial studies revealed the presence of 114 compounds, of which 92 were identified for the first time in the genus Dracocephalum. New identified metabolites belonged to 17 classes, including 16 phenolic acids and their conjugates, 18 flavones, 5 flavonols, 2 flavan-3-ols, 1 flavanone, 2 stilbenes, 10 anthocyanins, 1 condensed tannin, 2 lignans, 6 carotenoids, 3 oxylipins, 2 amino acids, 3 sceletium alkaloids, 3 carboxylic acids, 8 fatty acids, 1 sterol, and 3 terpenes, along with 6 miscellaneous compounds. It was shown that extracts of D. palmatum are richer in the spectrum of polyphenolic compounds compared with extracts of D. ruyschiana, according to a study of the presence of these compounds in extracts, based on the results of mass spectrometric studies.

Plants from Genus Dracocephalum in Iran: Pharmacology and Phytochemistry Overview

BACKGROUND

Genus Dracocephalum belongs to the Lamiaceae family, representing 11 species in Iran, containing D. ghahremanii Jamzad, D. lindbergii Rech. F, D. oligadenium Bornm. & Gauba, D. kotschyi Boiss., D.multicaule, D.Aucheri, D.Subcapitatum, D.Thymifolium, D.Moldavica, D. polychaetum Borm, and D. surmandinum Rech.f. The current study aimed to investigate the morphological and phytochemical properties of Dracocephalum species in Iran and their pharmacological effects.

METHODS

The search was restricted to scientific articles from PubMed, Google Scholar, Science Direct, SpringerLink, and Scopus. The search was limited to scientific journals, books, and book chapters focusing on the medicinal properties of Dracocephalum in Iran for the era from 1993 to 2020.

RESULTS

Findings show that Dracocephalum species were utilized to treat various disorders in traditional medicine. Phytochemical studies show that the main constituents isolated from the plant consist of lignans, phytosterol, flavonoids, phenols, alkaloids, Sesquiterpenes, and oxygenated and hydro carbonated monoterpenes. These main components are responsible for antihyperlipidemic, antimicrobial, anticancer, antispasmodic, antioxidant, and cardiovascular effects of the plant.

CONCLUSION

This plant has a good potential for drug discovery and curing different diseases. Therefore, more research will be done on the Iranian species of Dracocephalum based on clinical and animal studies to develop an effective drug formulation.

The Use of Moldavian Dragonhead Bagasse in Shaping the Thermophysical and Physicochemical Properties of Ice Cream

The aim of the study was to analyze the influence of bagasse from Moldavian dragonhead (D. moldavica L.) seeds as a source of valuable nutrients on the physicochemical properties of rice milk ice cream. The basic composition of the ice cream was modified with a varied proportion of Moldavian dragonhead bagasse (MDB) (1.0%, 1.5%, 2.0%, 2.5%, and 3.0%). The analysis of fatty acids showed a high proportion of linolenic acid (n-3) in the tested ice cream, especially with 3.0% share of bagasse. The addition of MDB increased dry matter, fat, and protein contents in the ice cream. The increasing share of this additive affected the physical properties of ice cream, increasing hardness, adhesiveness and viscosity, and reducing their melting rate. The study showed a negligible effect of the increasing share of MDB on the thermophysical properties of ice cream. Due to the high nutritional value of the bagasse (with the appropriate refinement of the recipe), it is possible to obtain rice milk ice cream with potential health-promoting properties.

UPLC-PDA-ESI-QTOF-MS/MS and GC-MS analysis of Iranian Dracocephalum moldavica L

Dracocephalum moldavica L. is a significant component in the Iranian food basket. This study aimed to investigate the bioactive compounds and biological activities of different extracts obtained from D. moldavica aerial parts. From the aerial parts, a crude methanolic (MeOH) extract and its four sub-fractions, that is, petroleum ether (Pet), ethyl acetate (EtOAc), n-butanol (n-BuOH), and aqueous (water) extracts were obtained. The total phenolic and flavonoid contents as well as the antioxidant and cytotoxic activities of the extracts were determined. Moreover, the phytochemical profiles of the essential oil (EO) and of those extracts with the highest antioxidant activity measured by GC/MS and UPLC-PDA-ESI-QTOF-MS/MS. Results showed that the highest concentrations of phenols and flavonoids as well as the most potent antioxidant potential according to the DPPH method were determined in the EtOAc and MeOH extracts with IC50 values of 22.0 and 34.4 µg.ml-1, respectively. Quantitative analysis of these extracts was subsequently performed by UPLC-PDA-ESI-QTOF-MS/MS. Both extracts contained mainly rosmarinic acid, caffeic acid, and 2-hydroxycinnamic acid, which may be responsible for their high antioxidant activity. Moreover, none of the extracts showed cytotoxic effects against MCF7, SW48, and a normal cell line of mouse embryonic fibroblast cells (NIH/3T3) in the tested concentrations (up to 400 μg.ml-1). Additionally, GC-MS analysis showed that oxygenated monoterpenes (55.4%) were the main constituents of the EO of D. moldavica.

Dracomolphin A-E, new lignans from Dracocephalum moldavica

Eight new lignans, dracomolphin A-E (1-8), together with eight known lignans (9-16) were isolated from the aerial part of Dracocephalum moldavica. The structures of the isolated compounds were established based on NMR and HRESIMS data. Dracomolphin A (1-4) was elucidated as a lignan possessed a 5-membered ketal ring formed between C-8' and C-3, C-4. The two stereogenic centers rendered dracomolphin A as a mixture of two diastereomeric pairs of enantiomers (1-4). All of the four isomers were separated successfully by using chiral HPLC and their stereochemical features were determined by CD spectra. Bioactivity screening revealed that compounds 1-4, 6, 7, 12, 15 and 16 were potential Nrf2 transcriptional activators. Dracomolphin E (8) reduced cell viability of lung cancer NCI-H292 cells associated with apoptosis.

In vitro and in vivo Anti-Toxoplasma activity of Dracocephalum kotschyi essential oil

Toxoplasma gondii is a zoonotic parasite of worldwide importance, responsible for toxoplasmosis in homeotherms. Although treatment options are readily available, most drugs often cause serious side effects. Extracts of Dracocephalum kotschyi (D. kotschyi) have shown significant pharmacological activity against various parasites, viruses, and bacteria. In this study, we evaluated the anti-T. gondii activity in vitro and in vivo of D. kotschyi essential oil. The thiazolyl blue tetrazolium bromide (MTT) method was used to assess the anti-T. gondii activity and cytotoxicity of the essential oil. The presence of T. gondii was observed by Giemsa staining, and the viability was evaluated by the trypan blue staining method. Furthermore, the survival rate of acutely infected mice was evaluated by intraperitoneal injecting of the essential oil (50, 100, and 200 mg kg-1 day-1) for five days after infection with 2 × 104 tachyzoites. Essential oil, negative, and positive controls that showed the best toxoplasmacidal activity were assayed in triplicate at each concentration. The essential oil exhibited the highest anti-Toxoplasma activity with a half-maximal inhibitory concentration (IC50) of 9.94 ± 0.38 µg, with a selectivity index of 2.463. On Vero cells, the CC50 of the oil was 24.49 ± 0.96 µg and exhibited a significant anti-Toxoplasma activity. Moreover, the treatment by essential oil significantly increased the survival rate compared to untreated infected control. In conclusion, the essential oil might be a useful compound, and with more testing, it may be an excellent alternative to standard chemical drugs in the treatment of toxoplasmosis.

Transformed Shoots of Dracocephalum forrestii W.W. Smith from Different Bioreactor Systems as a Rich Source of Natural Phenolic Compounds

Transformed shoots of the Tibetan medicinal plant Dracocephalum forrestii were cultured in temporary immersion bioreactors (RITA and Plantform) and in nutrient sprinkle bioreactor (NSB) for 3 weeks in MS (Murashige and Skoog) liquid medium with 0.5 mg/L BPA (N-benzyl-9-(2-tetrahydropyranyl)-adenine) and 0.2 mg/L IAA (indole-3-acetic acid). The greatest biomass growth index (GI = 52.06 fresh weight (FW) and 55.67 dry weight (DW)) was observed for shoots in the RITA bioreactor, while the highest multiplication rate was found in the NSB (838 shoots per bioreactor). The levels of three phenolic acids and five flavonoid derivatives in the shoot hydromethanolic extract were evaluated using UHPLC (ultra-high performance liquid chromatography). The predominant metabolite was rosmarinic acid (RA)—the highest RA level (18.35 mg/g DW) and total evaluated phenol content (24.15 mg/g DW) were observed in shoots grown in NSB. The NSB culture, i.e., the most productive one, was evaluated for its antioxidant activity on the basis of reduction of ferric ions (ferric reducing antioxidant power, FRAP) and two scavenging radical (O₂^•– and DPPH, 1,1-diphenyl-2-picrylhydrazyl radical) assays; its antibacterial, antifungal, and antiproliative potential against L929 cells was also tested (3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) test). The plant material revealed moderate antioxidant and antimicrobial activities and demonstrated high safety in the MTT test—no cytotoxicity at concentrations up to 50 mg/mL was found, and less than a 20% decrease in L929 cell viability was observed at this concentration.

Phytochemical composition profile and space-time accumulation of secondary metabolites for Dracocephalum moldavica Linn. via UPLC-Q/TOF-MS and HPLC-DAD method

The aerial parts of Dracocephalum moldavica L. are extensively used in traditional ethnic medicines in China as a remedy for cardiovascular and cerebrovascular damage. However, the chemical composition and the accumulation of main secondary metabolites of D. moldavica in different natural environments remain unclear. This study aimed to conduct a qualitative and quantitative analysis of the main secondary metabolites to explore the quality variation of D. moldavica in markets. The evaluation of space-time accumulation of main secondary metabolites in D. moldavica was carried out during different growth periods and in different geographical locations. A total of 35 ingredients were detected and 24 identified, including 21 flavonoids, two phenolic acids and one coumarin by UPLC-QTOF-MS method. Furthermore, a simple and convenient HPLC method was successfully developed for the simultaneous determination of lutelin-7-O-glucuronide and tilianin and rosmarinic acid in D. moldavica. The results of space-time accumulation analysis showed the distinct variation of secondary metabolites of D. moldavica with the growth period and geographical location. Finally, the current study provided a meaningful and useful approach for comprehensively evaluating the quality of D. moldavica.

The effect of purine-type cytokinin on the proliferation and production of phenolic compounds in transformed shoots of Dracocephalum forrestii

Dracocephalum forrestii is a perennial, endemic to China plant with a number of pharmaceutical properties. Transformed shoots of the species spontaneously regenerated from hairy roots induced by Agrobacterium rhizogenes. The transgenic nature of the shoots was confirmed by polymerase chain reaction (PCR). The shoot culture was multiplied on Murashige and Skoog (MS) medium with 0.2 mg/l IAA and 0.2, 0.5, 1.0, 2.0 or 5.0 mg/l purine-type cytokinins (mT, BAR, BPA or BAP). The highest multiplication rate (about thirteen shoot or buds per explant) was obtained on MS medium with 0.2 mg/l mT after four weeks of culture. The phenolic compounds present in the hydromethanolic extracts from the D. forrestii transgenic shoots were characterized using UPLC-PDA-ESI-MS. The shoots were found to biosynthesize three phenolic acids and five flavonoid glycosides. UHPLC analysis of the hydromethanolic extracts found the predominant phenolic acid to be rosmarinic acid, with its highest content observed in shoots cultivated with 5.0 mg/l BPA. In contrast, the greatest production of flavonoid derivatives (especially acacetin derivatives) was observed in the medium supplemented with 2 mg/l BPA.

Medicinal Properties and Active Constituents of Dracocephalum kotschyi and Its Significance in Iran: A Systematic Review

OBJECTIVES

Dracocephalum has over 60 species and is found mainly in the temperate regions of Asia and Europe. One of these species, i.e., Dracocephalum kotschyi Boiss, is known to have a number of medicinal properties and active ingredients in many parts of the world. Despite being an endemic wild-flowering plant of great importance, the plant is currently considered endangered in Iran. Besides, there is paucity of information on the significance of the medicinal properties and active constituents of D. kotschyi among the Iranian people. On that account a systematic review of studies reporting on the medicinal properties and active ingredients and its significance to human and animal health was conducted and the existing knowledge gaps were identified.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used in the search for published articles on medicinal properties and active ingredients of D. kotschyi and its significance on humans and animals in Iran. The search was confined to scientific articles from repositories of popular data bases and search engines among them PubMed, Web of Science, Google Scholar, Science Direct, SpringerLink, and Scopus. The search narrowed down on scientific journals, books, and book chapters focusing on the medicinal properties of D. kotschyi in Iran for the period between 1970 and 2018.

RESULTS

A total of 1158 scientific articles were sourced from the various databases, out of which 38 met the search criteria and qualified for this review. The studies were conducted in only 9 of the 31 provinces of Iran, with a large proportion in Isfahan province, central Iran. The studies showed that all plant parts (roots, aerial parts, flowers, and leaves) had active constituents. Essential oils and aerial plant parts were the main components studied. Nevertheless, the most frequently reported constituents were xanthomicrol, limonene, luteolin, geranial, apigenin, and calycopterin. A number of medicinal properties were reported among them antioxidant, antibacterial, anticancerous, antinociceptive, antihyperlipidemic, antispasmodic, cytotoxic, and immunomodulatory effects. The plant was also reported to be a remedy for inflammatory pain, headaches, congestion, liver disorders, ulcer, fever, renal pain, dyspepsia, stomach ache, abdominal pain, joints pains, muscle spasm, congestion, bloating, and wound healing effects, among others.

CONCLUSION

This review has shown that D. kotschyi is an important medicinal plant with a large number of active constituents and great potential to safeguard human and animal health in Iran. However, over utilization of the D. kotschyi plant is already endangering its existence. Nevertheless, more studies need be conducted across the country.

Cytotoxic Terpenoids from the Roots of Dracocephalum taliense

A chemical investigation of methanol extract from the roots of Dracocephalum taliense led to the isolation of a new aromatic abietane diterpenoid, 12-methoxy-18-hydroxy-sugiol (1), and one highly-oxygenated ursane triterpenoid, 2α,3α-dihydroxy-11α,12α-epoxy-urs-28,13β-olide (2), together with 15 known natural products (3–17). Among these, compounds 1–13 and 15–17 were detected for the first time in the genus of Dracocephalum. The structures of all of these isolates were determined by extensively spectroscopic analyses. In the anti-inflammatory assay, compounds 1 and 2 had no obvious inhibitory activity on the release of cytokine IL-2 in lipopolysaccharide-induced RAW 264.7 macrophages. However, compound 2 exhibited significant cytotoxic activity against cell lines HepG2 (IC₅₀ = 6.58 ± 0.14 μM) and NCI-H1975 (IC₅₀ = 7.17 ± 0.26 μM).

Effect of Low Temperature Cultivation on the Phytochemical Profile and Bioactivity of Arctic Plants: A Case of Dracocephalum palmatum

The influence of climatic factors, e.g., low temperature, on the phytochemical composition and bioactivity of the arctic plant Dracocephalum palmatum Steph. ax Willd. (palmate dragonhead), a traditional food and medical herb of Northern Siberia, was investigated. D. palmatum seedlings were grown in a greenhouse experiment at normal (20 °C, NT) and low (1 °C, LT) temperature levels and five groups of components that were lipophilic and hydrophilic in nature were characterized. The analyses indicated that D. palmatum under NT demonstrates high content of photosynthetic pigments, specific fatty acid (FA) profile with domination of saturated FA (53.3%) and the essential oil with trans-pinocamphone as a main component (37.9%). Phenolic compounds were identified using a combination of high performance liquid chromatography with diode array detection and electrospray ionization mass-spectrometric detection (HPLC-DAD-ESI-MS) techniques, as well as free carbohydrates and water soluble polysaccharides. For the first time, it was established that the cold acclimation of D. palmatum seedlings resulted in various changes in physiological and biochemical parameters such as membrane permeability, photosynthetic potential, membrane fluidity, leaf surface secretory function, reactive oxygen species-antioxidant balance, osmoregulator content and cell wall polymers. In brief, results showed that the adaptive strategy of D. palmatum under LT was realized on the accumulation of membrane or surface components with more fluid properties (unsaturated FA and essential oils), antioxidants (phenolic compounds and enzymes), osmoprotectants (free sugars) and cell wall components (polysaccharides). In addition, the occurrence of unusual flavonoids including two new isomeric malonyl esters of eriodictyol-7-O-glucoside was found in LT samples. Data thus obtained allow improving our understanding of ecophysiological mechanisms of cold adaptation of arctic plants.

Application of Moldavian dragonhead (Dracocephalum moldavica L.) leaves addition as a functional component of nutritionally valuable corn snacks

Application of Moldavian dragonhead (Dracocephalum moldavica L.) leaves in extruded snacks was evaluated. Directly expanded corn snacks (crisps) were supplemented with 5-20% of dragonhead leaves. The supplemented snacks were characterized to have improved nutritional value and were a good source of dietary fibre. The presence of phenolic compounds, especially rosmarinic acid, showed a high antioxidant potential and a radical scavenging activity of tested snacks, especially if a high content of additive was used. The increasing amount of additive also had an impact on the physical properties of extrudates lowering the expansion ratio, water absorption and solubility, yet increasing bulk density, cutting force and the breaking index of the enriched snacks. The highest viscosity was observed at 5 and 10% addition level. The increasing amount of dragonhead leaves lowered the brightness of snacks and increased the greenness tint significantly. A sensory evaluation showed good acceptability of snacks enriched with up to 15% of dragonhead dried leaves. Dried leaves of the Moldavian dragonhead seem to be a prospective functional additive for extruded crisps with a high nutritional value, especially because of dietary fibre and rosmarinic acid content, a strong antioxidant potential and acceptable sensory properties.

Preparative Capillary GC for Characterization of Five Dracocephalum Essential Oils from Mongolia, and their Mosquito Larvicidal Activity

The chemical composition and mosquito larvicidal and adulticidal activity of five essential oils (EOs), Dracocephalum ruyschiana L. (DR), D. foetidum Bunge (DF), D. moldavica L. (DM), D. fruticulosum Steph. ex Willd. (DFr) and D. peregrinum L. (DP) were evaluated. Simultaneous GC-FID and GC-MS analyses revealed in the EOs of DR, DF and DM an unidentified compound (1) ([M+122], 5.4%, 57.9% and 74.0%, respectively). Therefore, we aimed to isolate compound 1 using Preparative Capillary GC (PCGC) connected to a Preparative Fraction Collector (PFC) system. Structure determination of 1 was determined by 1H- and 13C-NMR as p-mentha-1,8-dien-10-al (1, limonen-10-al). Other detected major constituents were thymol (34.0%) and carvacrol (6.1%) in DR; limonene (28.8%) in DF; cis-chrysanthenol acetate (29.1%) and trans-verbenol (5.0%) in DFr; and linalool (17.9%), trans-β-bergamotene (7.9%), (E)-nerolidol (7.7%) and eugenol (5.5%) in DP. The DFr, DP, DR and DM EOs produced 100% mortality to 1st instar larvae of Aedes aegypti L. at 250 ppm and DR and DM EO exhibited the strongest activity and killed 100% 1st instar larvae at 62.5 ppm. No adulticidal activity was observed against female Ae. aegypti. In the scope of the present study, for the first time isolation of limonen-10-al (1) from DR, DM, and DP EOs and larvicidal activity of five Dracocephalum EOs were reported.

Development of HPLC Protocol and Simultaneous Quantification of Four Free Flavonoids from Dracocephalum heterophyllum Benth

Quantification of the four flavonoids, namely, luteolin, kaempferol, diosmetin, and chrysosplenetin, has been performed for the first time in 80% ethanolic extract of Dracocephalum heterophyllum B. through HPLC coupled to UV detector after optimization of extracting solvent and chromatographic conditions. Total flavonoids quantified were 0.324 mg/mL of the extract. HPLC analysis delivered contents of the luteolin, kaempferol, diosmetin, and chrysosplenetin as 0.08%, 0.14%, 0.28%, and 0.79% of the dried extract, respectively. LOD (%) values calculated were 0.04, 0.03, 0.03, and 0.08 and LOQ (%) values were 0.08, 0.12, 0.11, and 0.28 for luteolin, kaempferol, diosmetin, and chrysosplenetin, respectively. The recovery percentages for these flavonoids were within the acceptable range of 95% to 105%. Standard deviation and %RSD were calculated for each target analytes individually in extract for determining the reproducibility and accuracy of the method. In no case the %RSD was higher than 1 taking retention time as a factor while in the case of area under the curve maximum %RSD was noted in the case of diosmetin as 2.85. From our literature review regarding the plant species under study, it appears that these flavonoids have not been quantified before and are reported for the first time in this paper.

Chemical Composition and Biological Activity of Essential Oils of Dracocephalum heterophyllum and Hyssopus officinalis from Western Himalaya

The essential oils of two representatives of the Lamiaceae, Dracocephalum heterophyllum Benth. and Hyssopus officinalis L., are described for their antifungal, antibacterial, larvicidal and inect biting deterrent activities. Additionally, the chemical compositions of the essential oils, analyzed by simultaneous GC-MS and GC-FID, and odor descriptions are given. The main components of H. officinalis oil were pinocarvone, cis-pinocamphone, and β-pinene. Citronellol was found as the main compound of D. heterophyllum essential oil. Antibacterial testing by agar dilution assay revealed greater activity of D. heterophyllum against Staphylococcus aureus compared with H. officinalis. D. heterophyllum essential oil also showed promising antifungal activity against Colletotrichum species and was more toxic to Aedes aegypti larvae in a larvicial bioassay. Both essential oils showed high activity in the biting deterrent bioassay.

Monoterpene glycosides, phenylpropanoids, and acacetin glycosides from Dracocephalum foetidum

Chemical investigation of the acetone extract from the aerial parts of the Mongolian medicinal plant Dracocephalum foetidum resulted in the isolation of three limonene glycosides, a caffeic acid trimer, four rosmarinic acid glucosides, and five acacetin acyl glycosides, together with 13 known natural products. The chemical structures of all of the compounds were determined by spectroscopic analyses. Among these compounds three showed hyaluronidase inhibitory activity. In addition, one other compound showed stronger 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity than the positive control Trolox, whereas three other compounds demonstrated a similar activity to that of Trolox.

Chemical composition and antioxidant activity of Tánara Ótó (Dracocephalum palmatum Stephan), a medicinal plant used by the North-Yakutian nomads

Dracocephalum palmatum Stephan (Lamiaceae) is a medicinal plant used by the North-Yakutian nomads. From the crude ethanolic extract of the aerial parts of this plant, 23 compounds (phenylpropanoids, coumarins, flavonoids, and triterpenes) were isolated. Among these, eight compounds (salvianolic acid B, caftaric acid, cichoric acid, umbelliferone, aesculetin, apigenin-7-O-β-D-glucuronopyranoside, isorhoifolin, and luteolin-4'-O-β-D-glucopyranoside) were detected for the first time in the genus Dracocephalum. Their structures were elucidated based on chemical and spectral data. The levels of most of the compounds detected in the cultivated sample were close to that of the wild sample, indicating the reproducibility of the biologically active compounds of D. palmatum through cultivation. Investigation into the biological activity of D. palmatum under in vitro conditions demonstrated that its extracts have a strong antioxidant effect due to the presence of high concentrations of phenolic compounds.

Flavone tetraglycosides and benzyl alcohol glycosides from the Mongolian medicinal plant Dracocephalum ruyschiana

From an extract of the aerial parts of Dracocephalum ruyschiana, five new flavone tetraglycosides, five new benzyl alcohol glycosides, and 19 known compounds were isolated. The tetraglycosides contain a 7-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→6)]-β-d-glucopyranosyl moiety. The benzyl alcohol glycosides had acyl groups on their glycosyl or aglycone moieties. The compounds were tested for antioxidant activity using DPPH. Although the new compounds were not active, phenylpropanoylquinic acid derivatives were revealed as radical scavengers in D. ruyschiana.

Phenolic alkaloids from the aerial parts of Dracocephalum heterophyllum

Chemical examination of aerial parts of Dracocephalum heterophyllum resulted in isolation of phenolic alkaloids, including two flavonoidal alkaloids, drahebephins A and B, one imidazole alkaloid with a phenolic substituent, drahebenine, together with 15 other known compounds. Their structures were established by extensive spectroscopic data analyses. Due to the stereogenic center in the pyrrolidin-2-one ring, the flavonoidal alkaloids are chiral, although they were isolated as racemates. The enantiomers were separated by HPLC using a chiral phase and stereochemically characterized by circular dichroism (CD) spectroscopy. The structure of compound drahebenine was established by X-ray crystallography.

Chromone and flavonoid alkaloids: occurrence and bioactivity

The chromone and flavonoid alkaloids represent an unusual group of structurally diverse secondary metabolites, derived from the convergence of multiple biosynthetic pathways that are widely distributed through the plant and animal kingdoms. Many of them have been discovered through bioassay-guided chemical investigations of traditional medicines, suggesting potential therapeutic significance. Their unique structures and varied pharmacological activities may provide important new leads for the discovery of drugs with novel mechanisms of action. Potential therapeutic indications are as diverse as cancer and viral infections, inflammation and immunomodulation, neurological and psychiatric conditions, and diabetes.