Phytochemical and comparative transcriptome analyses reveal different regulatory mechanisms in the terpenoid biosynthesis pathways between Matricaria recutita L. and Chamaemelum nobile L.

BACKGROUND: Matricaria recutita (German chamomile) and Chamaemelum nobile (Roman chamomile) belong to the botanical family Asteraceae. These two herbs are not only morphologically distinguishable, but their secondary metabolites - especially the essential oils present in flowers are also different, especially the terpenoids. The aim of this project was to preliminarily identify regulatory mechanisms in the terpenoid biosynthetic pathways that differ between German and Roman chamomile by performing comparative transcriptomic and metabolomic analyses. RESULTS: We determined the content of essential oils in disk florets and ray florets in these two chamomile species, and found that the terpenoid content in flowers of German chamomile is greater than that of Roman chamomile. In addition, a comparative RNA-seq analysis of German and Roman chamomile showed that 54% of genes shared > 75% sequence identity between the two species. In particular, more highly expressed DEGs (differentially expressed genes) and TF (transcription factor) genes, different regulation of CYPs (cytochrome P450 enzymes), and rapid evolution of downstream genes in the terpenoid biosynthetic pathway of German chamomile could be the main reasons to explain the differences in the types and levels of terpenoid compounds in these two species. In addition, a phylogenetic tree constructed from single copy genes showed that German chamomile and Roman chamomile are closely related to Chrysanthemum nankingense. CONCLUSION: This work provides the first insights into terpenoid biosynthesis in two species of chamomile. The candidate unigenes related to terpenoid biosynthesis will be important in molecular breeding approaches to modulate the essential oil composition of Matricaria recutita and Chamaemelum nobile.

Acid-Induced Rearrangement of Epoxygermacranolides: Synthesis of Furanoheliangolides and Cadinanes from Nobilin.

The acid-induced rearrangement of three epoxyderivatives of nobilin 1, the most abundant sesquiterpene lactone in Anthemisnobilis flowers, was investigated. From the 1,10-epoxyderivative 2, furanoheliangolide 5 was obtained, while the 4,5-epoxy group of 3 did not react. Conversely, when the 3-hydroxy function of nobilin was acetylated (12), the 4,5-epoxy derivative did cyclize into cadinanes (15 and 16) under Lewis acid catalysis. The reactivity of the 4,5- and 1,10-epoxy derivatives of nobilin (2 and 3) was compared with that of parthenolide, and rationalized on the basis of quantum chemical calculations. All isolated reaction products were fully characterized by spectroscopic and computational methods, and their in vitro anti-protozoal activity was evaluated. The paper could provide new insights into the biosynthesis of this class of natural products.

Octulosonic acid derivatives from Roman chamomile (Chamaemelum nobile) with activities against inflammation and metabolic disorder.

Six new octulosonic acid derivatives (1-6) were isolated from the flower heads of Roman chamomile (Chamaemelum nobile). Their structures were elucidated by means of spectroscopic interpretation. The biological activity of the isolated compounds was evaluated toward multiple targets related to inflammation and metabolic disorder such as NAG-1, NF-κB, iNOS, ROS, PPARα, PPARγ, and LXR. Similar to the action of NSAIDs, all the six compounds (1-6) increased NAG-1 activity 2-3-fold. They also decreased cellular oxidative stress by inhibiting ROS generation. Compounds 3, 5, and 6 activated PPARγ 1.6-2.1-fold, while PPARα was activated 1.4-fold by compounds 5 and 6 only. None of the compounds showed significant activity against iNOS or NF-κB. This is the first report of biological activity of octulosonic acid derivatives toward multiple pathways related to inflammation and metabolic disorder. The reported anti-inflammatory, hypoglycemic, antiedemic, and antioxidant activities of Roman chamomile could be partly explained as due to the presence of these constituents.

Mycotoxicogenic fungal inhibition by innovative cheese cover with aromatic plants.

BACKGROUND: The use of aromatic plants and their extracts with antimicrobial properties may be compromised in the case of cheese, as some type of fungal starter is needed during its production. Penicillium verrucosum is considered a common cheese spoiler. The aim of this study was to evaluate the innovative use of certain aromatic plants as natural cheese covers in order to prevent mycotoxicogenic fungal growth (P. verrucosum). A collection of 12 essential oils (EOs) was obtained from various aromatic plants by solvent-free microwave extraction technology, and volatile characterisation of the EOs was carried out by gas chromatography/mass spectrometry. RESULTS: The most effective EOs against P. verrucosum were obtained from Anethum graveolens, Hyssopus officinalis and Chamaemelum nobile, yielding 50% inhibition of fungal growth at concentration values lower than 0.02 µL mL⁻¹. All EOs showed high volatile heterogeneity, with α-phellandrene, pinocamphone, isopinocamphone, α-pinene, camphene, 1,8-cineole, carvacrol and trans-anethole being found to be statistically significant in the antifungal model. CONCLUSION: The use of these aromatic plants as natural covers on cheese can satisfactorily inhibit the growth of some mycotoxicogenic fungal spoilers. Among the volatile compounds present, α- and ß-phellandrene were confirmed as the most relevant in the inhibition.

[Comparison of antioxidant activity between two species of chamomiles produced in Xinjiang by TLC-bioautography].

OBJECTIVE: To compare the antioxidant active components from two species of chamomile-matricaria and Roman chamomile produced in Xinjiang. METHOD: The TLC-bioautography was used, with 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical as the experimental model. The peak areas of various antioxidant components were obtained by TLC-scanning for analyzing antioxidant active components contained in volatile oil extracts and flavone extracts from the two species of chamomiles. The total peak area was taken as the indicator for comparing the antioxidant capacities of the two types of extracts, and comparing them with the total antioxidant activity of flavone extracts of the two species of chamomiles. RESULTS: According to the result of TLC-bioautography in volatile oil extracts from the two species of chamomiles, volatile oil extracts from chamomile showed four white antioxidant spots, including en-yne-dicycloether, and volatile oil extracts from Roman chamomile showed only one white antioxidant spot. The TLC-scanning result showed that the peak area of antioxidant spots of volatile oil extracts from chamomile was significantly larger than that of volatile oil extracts from Roman chamomile. According to the test on the antioxidant activity of the two species of chamomiles with ultraviolet-visible spectrophotometry, the concentration of chamomile after scavenging 50% of DPPH radicals was 0.66 g x L(-1), whereas the figure for Roman chamomile was 0.33 g x L(-1). According to the result of TLC-bioautography in flavone extracts from the two species of chamomiles, flavone extracts from chamomile showed seven yellowish antioxidant spots, including apigenin and apigenin-7-glucoside, and flavone extracts of Roman chamomile showed eight yellowish antioxidant spots, including apigenin and apigenin-7-glucoside. The TLC-scanning results showed that the peak area of antioxidant spots of flavone extracts from Roman chamomile was significantly larger than that of flavone extracts from chamomile. CONCLUSION: Volatile oil extracts from the two species of chamomiles have significant difference in the antioxidant activity in TLC-bioautography. Specifically, the antioxidant activity of volatile oil extracts from chamomile is stronger than volatile oil extracts from Roman chamomile; the known antioxidant active components in volatile oil extracts from chamomile is en-yne-dicycloether, while all of the other three antioxidant active components as well as antioxidant active components in volatile oil extracts from Roman chamomile are unknown components and remain to be further determined. Considering the significant difference in the number of antioxidant active spots in volatile oil extracts from the two species of chamomiles, the result can be applied to distinguish the two species of chamomiles. The antioxidant activity determination result for flavone extracts from two species of chamomiles was consistent with the result of TLC-bioautography, showing that flavone extracts from chamomile and Roman chamomile are more antioxidant active, while that of Roman chamomile is stronger than chamomile. Flavone extracts from both of the two species of chamomiles contain apigenin and pigenin-7-glucoside, which are known, while all of the other five antioxidant active components contained in flavone extracts from chamomile and the other six antioxidant active components contained in flavone extracts from Roman chamomile are unknown and remain to be further identified. The method lays a foundation for further identification of antioxidant active components contained in chamomile.

Valorisation of Roman chamomile (Chamaemelum nobile L.) herb by comprehensive evaluation of hydrodistilled aroma and residual non-volatile fractions.

Valorization of botanicals for the development of natural food-grade ingredients is an important task in terms of sustainability and processing waste reduction. In this study, Roman chamomile (Chamaemelum nobile L.) herb was collected at six different vegetation phases in the period 26 May - 23 August 2019 and subjected to biorefining into the several valuable fractions. The yield of hydro-distilled essential oil (EO) was in the range of 0.22% (intensive vegetative growth) to 0.80% (full flowering). Angelic, isobutyric, butyric and methacrylic acid esters and some monoterpene and sesquiterpene derivatives were the major EO constituents: 3-methylpentyl angelate (20.11-27.56%), methallyl angelate (7.28-10.33%), isoamyl angelate (5.57-9.02%), isobutyl angelate (4.84-6.79%), 2-methylbutyl angelate (3.11-6.32%), 3-methylamyl methacrylate (5.04-6.17%), 3-methylpentyl isobutyrate (4.29-6.64%), 3-methylamyl isobutyrate (4.29-6.64%), α-pinene (1.61-6.37%) and pinocarvone (1.46-4.67%). In order to valorize water soluble and solid EO distillation residues their antioxidant potential was evaluated by several in vitro assays: water extracts were considerably stronger antioxidants than acetone extracts isolated from the solid residues. Water extracts of the plants collected at flowering phases were the strongest antioxidants; their TPC, FRAP and ORAC values were up to 143.2 mg gallic acid equivalents/g, 650, and 5601 µmol TE/g dry extract, respectively, while effective concentrations (EC50) of DPPH• and ABTS•+ scavenging, were down to 0.59 and 0.49 mg/mL, respectively. Among 7 tentatively identified by UPLC/Q-TOF/MS phenolic constituents the intensity of molecular ion of 3,5-dicaffeoyl quinic acid was the largest. The results obtained may assist for developing flavorings, antioxidants and health beneficial preparations from C. nobile extracts.

Roman chamomile inhalation combined with clomipramine treatment improves treatment-resistant depression-like behavior in mice.

It is well known that chamomile is one of the oldest known medicinal herbs and has been used to treat various disorders, but it is mainly German chamomile. The effects of Roman chamomile on depression still unclear. In this study, we used chronically stressed mice to investigate whether inhalation of Roman chamomile essential oil affects depression-like behavior. We previously reported that restraint and water immersion stress produce depression-like behavior and a blunted response to the tricyclic antidepressant clomipramine. Each mouse was exposed to restraint and water immersion stress for 15 days, and resistance to the effect of clomipramine was induced in a behavioral despair paradigm. In the present study, we found that cotreatment with clomipramine and inhalation of Roman chamomile attenuated depression-like behavior in a forced swim test. Next, we examined the hippocampal mRNA levels of two cytokines, tumor necrosis factor (TNF) alpha and interleukin-6 (IL-6); a neurotrophic factor, brain derived-neurotrophic factor (BDNF); and nerve growth factor (NGF). TNF alpha, IL-6 and BDNF mRNA levels did not change in the hippocampus of stressed mice. However, the NGF mRNA level was significantly decreased, and this decrease was not attenuated by treatment with clomipramine or inhalation of Roman chamomile alone. We also examined whether Roman chamomile combined with clomipramine treatment affects hippocampal neurogenesis and serum corticosterone levels. Stressed mice had fewer doublecortin (DCX)-positive cells in the subgranular zone of the dentate gyrus, but this was significantly attenuated by Roman chamomile and clomipramine treatment. In addition, the serum corticosterone level was also significantly decreased by treatment with Roman chamomile and clomipramine. These results suggest that Roman chamomile inhalation may enhance the antidepressant effect of clomipramine by increasing hippocampal neurogenesis and modulating corticosterone levels in patients with treatment-resistant depression.

In vivo Antibacterial and Wound Healing Activities of Roman Chamomile (Chamaemelum nobile).

BACKGROUND: Today considerable number of drugs are produced from plants. Several plants with antibacterial and healing applications are used in medicine such as Roman chamomile (Chamaemelum nobile L.). Wound infection is one of the most prevalent infections among infectious diseases around the world. Due to appearance of drug resistance, researchers are now paying attention to medicinal plants. Therefore, this study was designed to investigate the antimicrobial and wound healing properties of C. nobile against Pseudomonas aeruginosa using in vivo conditions. METHODS: Ethanolic extract of C. nobile was provided using standard method. The 5% C. nobile ointment was prepared by dissolving lyophilized extract in eucerin. Forty five male rats were obtained from Ilam university. After anesthetization and wound creation, wounds were infected by P. aeruginosa. The rats were divided into three groups, group I was treated with C. nobile ointment, group II was treated with tetracycline ointment and the third group was treated with base gel as control group. RESULTS: Antibacterial and wound healing activities of C. nobile ointment were more than tetracycline ointment significantly. Our results indicated that extract of C. nobile had effective antibacterial activity and accelerated the progression of wound healing. CONCLUSION: Our study indicated that antibacterial and wound healing activities of C. nobile ointment were notable. C. nobile therapy in combination with antibiotics can also be useful because medicinal plants contents operate in synergy with antibiotics. These results revealed the value of plant extracts to control antibiotic resistant bacteria in wound infections.

Evaluation of antioxidant and antifungal properties of the traditional plants against foodborne fungal pathogens.

OBJECTIVE: To determine the antioxidant and antifungal activities of the essential oils from five aromatic herbs, including Thymus vulgaris, Chamaemelum nobile, Ziziphora clinopodioides, Zingiber officinale and Cuminum cyminum, against different Aspergillus and Penicillium species. METHODS: The oils were subjected to screening for their possible antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The susceptibility test for the oils was carried out in terms of minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) using microdilution method. RESULTS: The values of the essential oils in DPPH assay were as follows: T. vulgaris (450.11±5.23 µg/mL), Ch. nobile (602.73±4.8 µg/mL), Ziz. clinopodioides (1238.82±9.3 µg/mL), Cu. cyminum (1255.52±8.92 µg/mL) and Zin. officinale (5595.06±8.24 µg/mL). Our findings also indicated a strong activity against tested fungi for the oil of T. vulgaris (1250 µg/mL), followed by Cu. cyminum (1416 µg/mL), Zin. officinale (1833 µg/mL), Ziz. clinopodioides (2166 µg/mL) and Ch. nobile (3750 µg/mL). This study confirmed the excellent antifungal and antioxidant properties of the essential oils, especially T. vulgaris, against foodborne pathogenic fungi. CONCLUSION: Owing to their strong protective features, these oils could be used in ethno-medicine as preventers of lipid peroxidation and cellular damage, and in food industries as preservers of foodstuffs against spoilage fungi. Also, they could be the candidates to develop new antibiotics and disinfectants to control infective agents.

Green synthesis of CuO nanoparticles by aqueous extract of Anthemis nobilis flowers and their catalytic activity for the A³ coupling reaction.

CuO nanoparticles (NPs) were prepared by Anthemis nobilis flowers extract as a reducing and stabilizing agent and employed in catalyzing an aldehyde-amine-alkyne coupling reaction. The synthesized CuO NPs was characterized by SEM, EDS, XRD, FT-IR and UV-visible techniques. A diverse range of propargylamines were obtained in a good to high yield. Furthermore, the separation and reuse of CuO NPs was very simple, effective and economical.

Antibacterial, anti-swarming and anti-biofilm formation activities of Chamaemelum nobile against Pseudomonas aeruginosa.

INTRODUCTION: Chamomile (Chamaemelum nobile) is widely used throughout the world, and has anti-inflammatory, deodorant, bacteriostatic, antimicrobial, carminative, sedative, antiseptic, anti-catarrhal, and spasmolytic properties. Because of the increasing incidence of drug-resistant bacteria, the development of natural antibacterial sources such as medical herbs for the treatment of infectious diseases is necessary. Extracts from different plant parts such as the leaves, flowers, fruit, and bark of Combretum albiflorum, Laurus nobilis , and Sonchus oleraceus were found to possess anti-quorum sensing (QS) activities. In this study, we evaluated the effect of C. nobile against Pseudomonas aeruginosa biofilm formation. METHODS: The P. aeruginosa samples were isolated from patients with different types of infection, including wound infection, septicemia, and urinary tract infection. The flowers of C. nobile were dried and the extract was removed using a rotary device and then dissolved in dimethyl sulfoxide at pH 7.4. The microdilution method was used to evaluate the minimum inhibitory concentration (MIC) of this extract on P. aeruginosa , and biofilm inhibition was assayed. RESULTS: Eighty percent of the isolated samples (16/20) could form a biofilm, and most of these were isolated from wound infections. The biofilm inhibitory concentration of the C. nobile extract was 6.25-25mg/ml, whereas the MIC was 12.5-50mg/ml. CONCLUSIONS: The anti-QS property of C. nobile may play an important role in its antibacterial activity, thus offering an additional strategy in the fight against bacterial infections. However, molecular investigation is required to explore the exact mechanisms of the antibacterial action and functions of this phytocompound.

Nutrients, phytochemicals and bioactivity of wild Roman chamomile: a comparison between the herb and its preparations.

Roman chamomile, Chamaemelum nobile L. (Asteraceae), has been used for medicinal applications, mainly through oral dosage forms (decoctions and infusions). Herein, the nutritional characterisation of C. nobile was performed, and herbal material and its decoction and infusion were submitted to an analysis of phytochemicals and bioactivity evaluation. The antioxidant activity was determined by free radicals scavenging activity, reducing power and inhibition of lipid peroxidation, the antitumour potential was tested in human tumour cell lines (breast, lung, colon, cervical and hepatocellular carcinomas), and the hepatotoxicity was evaluated using a porcine liver primary cell culture. C. nobile proved to be an equilibrated valuable herb rich in carbohydrates and proteins, and poor in fat, providing tocopherols, carotenoids and essential fatty acids (C18:2n6 and C18:3n3). Moreover, the herb and its infusion are a source of phenolic compounds (flavonoids such as flavonols and flavones, phenolic acids and derivatives) and organic acids (oxalic, quinic, malic, citric and fumaric acids) that showed antioxidant and antitumour activities, without hepatotoxicity. The most abundant compounds in the plant extract and infusion were 5-O-caffeoylquinic acid and an apigenin derivative. These, as well as other bioactive compounds, are affected in C. nobile decoction, leading to a lower antioxidant potential and absence of antitumour potential. The plant bioactivity could be explored in the medicine, food, and cosmetic industries.

Chemical compositions of the essential oils of the aerial parts of Chamaemelum mixtum (L.) Alloni.

The chemical compositions of the aerial parts essential oils of Chamaemelum mixtum (L.) Alloni from Corsica and Sardinia were investigated employing gas chromatography and gas chromatography-mass spectrometry (GC-MS). The structure of (Z)-heptadeca-9,16-dien-7-one, a natural compound not previously described, was elucidated by GC-MS (electron impact and chemical ionization) and one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy. The variation in C. mixtum essential oil was studied, and statistical analysis showed the clustering of oil samples into three groups according to the amount of oxygenated compounds; these groups correlated to the harvest area. The strong biological activity of the oxygenated fraction (minimum inhibitory concentration of <0.1 mg/mL) of the Corsican oil against Candida albicans , Citrobacter frendii , Enterococcus faecalis , Escherichia coli , Klebsiella pneumoniae , Listeria monocytogenes , and Staphyllococcus aureus can be attributed to the presence of irregular monoterpene alcohols and (Z)-heptadeca-9,16-dien-7-one.

Antibacterial, anti-swarming and anti-biofilm formation activities of Chamaemelum nobile against Pseudomonas aeruginosa

Chamomile ( Chamaemelum nobile ) is widely used throughout the world, and has anti-inflammatory, deodorant, bacteriostatic, antimicrobial, carminative, sedative, antiseptic, anti-catarrhal, and spasmolytic properties. Because of the increasing incidence of drug-resistant bacteria, the development of natural antibacterial sources such as medical herbs for the treatment of infectious diseases is necessary. Extracts from different plant parts such as the leaves, flowers, fruit, and bark of Combretum albiflorum, Laurus nobilis , and Sonchus oleraceus were found to possess anti-quorum sensing (QS) activities. In this study, we evaluated the effect of C. nobile against Pseudomonas aeruginosa biofilm formation

Quantification of spiroether isomers and herniarin of different parts of Matricaria matricarioides and flowers of Chamaemelum nobile.

A simple HPLC-PAD-MS method was established to quantitatively analyse two spiroether isomers (cis-en-yn-dicycloether and trans-en-yn-dicycloether) and the main coumarin, herniarin, in chamomile herbs, simultaneously. By using this method, the contents of these three compounds in the flowers of two chamomile species, Roman chamomile (Chamaemelum nobile) and pineapple weed (Matricaria matricarioides), as well as in different parts of pineapple weed, were investigated. It was found that the flowers of both herbs contained large amounts of cis-en-yn-dicycloether and trans-en-yn-dicycloether, with the trans-form being more abundant than the cis-form. The leaves of pineapple weed were found to have the highest concentration of cis-en-yn-dicycloether and herniarin than the other parts. HPLC-PAD-MS-guided isolation and identification of other constituents are also discussed.