Chemical composition and potential antioxidant, anti-inflammatory, and analgesic efficacy of Cistus albidus L

This study aims to assess the chemical composition of the aqueous extract of Cistus albidus L. leaves, as well as the potential of aqueous and hydroethanol extracts of the leaves and seeds as analgesic, anti--inflammatory, and antioxidant agents. The contents of phenolics and inorganic constituents were determined in C. albidus seeds and leaves; antioxidant capacity was assessed by 3 complementary and diverse tests. The carrageenan-induced paw edema technique was used to investigate the anti-inflammatory effect in vivo, and albumin denaturation to evaluate the anti-inflammatory effect in vitro. The acetic acid-induced contortion test, the tail-flick test, and the plantar test were used to assess the analgesic effi cacy in vivo. Chemical analysis was performed by UPLC-MS/MS to quantify several phenolic compounds including catechin (1,627.6 mg kg-1), quercitrin (1,235.8 mg kg-1) and gallic acid (628. 2 mg kg-1). The ICP analysis revealed that potassium and calcium were the main inorganic components in the seeds and leaves of C. albidus. The hydroethanolic extract of the leaves showed the highest content of polyphenols/flavonoids, whereas the highest value of proantho cyanidins was detected in the aqueous extract of the seeds. All extracts showed potent antioxidant activity related to different phenolic compounds (quercetin, gallic acid, astragalin, catechin, and rutin). The aqueous extract of the leaves strongly inhibited paw edema (76.1 %) after 6 h of treatment and showed maximal inhibition of protein denaturation (191.0 µg mL-1 for 50 % inhibition) and analgesic activity in different nociceptive models. The presented data reveal that C. albidus extracts potentially show antioxidant, anti-inflammatory, and analgesic activities that could confirm the traditional use of this plant.

Identification of bioactive components on antihemorrhoidal activity of Cistus laurifolius L. using RP-HPLC and LC-QTOF-MS

ETHNOPHARMACOLOGICAL RELEVANCE

Cistus laurifolius is widely used in folk medicine in Anatolia for the treatment of many ailments. The leaves of the plant are used in the form of tea in the treatment of hemorrhoids in the Western Black Sea Region and Central Anatolia.

AIMS OF THE STUDY

It was aimed at evaluating the anti-hemorrhoidal effects of C. laurifolus leaves in croton oil-induced hemorrhoid model in rats.

MATERIALS AND METHODS

The methanolic and aqueous extracts of C. laurifolius were tested for in vivo anti-hemorrhoidal efficacy using an experimental hemorrhoid model, followed by histological and biochemical analysis. Hemorrhoid was created by using croton oil on the anal region of the rats. TNF-α and VEGF mRNA expression levels were assessed using real-time PCR detections. The extract was also tested for anti-inflammatory properties, which are based on the suppression of an increase in capillary permeability caused by acetic acid. LC-QTOF-MS and RP-HPLC were used for the phytochemical analysis.

RESULTS

In comparison to the control, histological and biochemical assessment showed that the methanolic extract of C. laurifolius is particularly effective against hemorrhoids. The same extract group's TNF-α mRNA expression was found to be the lowest. Additionally, the methanolic extract showed a strong inhibitory effect on the increase in capillary permeability resulted on by acetic acid. Three phenolic compounds were discovered in the extracts by phytochemical analyses, while more than eighteen compounds were found by LC-QTOF-MS analysis. Five of these compounds are phenolic acid derivatives, and flavonoids constitute the majority of the group.

CONCLUSION

This is the first evidence from the research that C. laurifolius possesses strong anti-inflammatory and anti-hemorrhoidal properties.

Ionomic analysis, polyphenols characterization, analgesic, antiinflammatory and antioxidant capacities of Cistus laurifolius leaves: in vitro, in vivo, and in silico investigations

This study aims to investigate the chemical and mineral composition, antioxidant, analgesic, and anti-inflammatory effects of the aqueous extract of Cistus laurifolius var. atlanticus Pit. (Cistaceae). Additionally, molecular docking interactions of various ligands with antioxidant protein target urate oxidase (1R4U) and anti-inflammatory protein target cyclooxygenase-2 (3LN1), revealing potential dual activities and highlighting specific residue interactions. The chemical characterization focused at first glance on the mineral composition which showed that C. laurifolius extract is a mineral-rich source of potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), phosphorus (P), and zinc (Zn). We next performed, ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis, the latter showed various polyphenols in C. laurifolius extract including Gallic acid as the predominant polyphenol. Isoquercetin, Taxifolin and Astragalin were also among the major flavonoids detected. The antioxidant capacity of C. laurifolius leaves was tested using 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1- picrylhydrazyl (DPPH) and reducing power (RP) assays. In vitro analysis of the anti-inflammatory property of C. laurifolius leaves was conducted by the albumin denaturation test and the in vivo was assessed in the sequel by carrageenan-induced paw edema test. The analgesic activity was evaluated in vivo using tail flick, acetic acid-induced contortion, and plantar tests. The findings showed that the leave extract had a powerful antioxidant activity with an IC50 values of 2.92 ± 0.03 µg/mL (DPPH) and 2.59 ± 0.09 µg/mL (in RP test). The studied extract strongly abolished the induced inflammation (82%). Albumin denaturation test recorded an IC50 value of 210 µg/mL. Importantly, the oral administration of C. laurifolius extract considerably reduced the nociceptive effect of acetic acid in rats, showing a significant analgesic effect in a dose-related manner. Altogether, our results showed that C. laurifolius can be a promising source of phytochemicals for drug development potential.

Spatial Variation in Yield, Chemical Composition, and Phytotoxic Activity of Cistus ladanifer Essential Oils

Cistus ladanifer L. (rockrose) is a widespread shrub species of the Mediterranean region with products highly valued by the perfume and cosmetics industry. In this research, the variability in yield, chemical composition and phytotoxic activity of C. ladanifer essential oils collected from 12 plots belonging to four natural populations and settled on two different types of edaphic substrates were evaluated. The essential oils were analyzed by GC-MS. The essential oil content ranged from 0.19 to 0.42 mL/100 g. The volatile profiles were found to be rich in oxygenated sesquiterpenes and oxygenated monoterpenes. PCA analysis clustered the samples into two groups that were mainly attributed to the type of substrate on which the plants grow. Furthermore, CCA and correlation analysis revealed that soil organic matter was the most effective edaphoclimatic driver accounting for these high levels of variation in essential oil yield and composition. Finally, C. ladanifer essential oils showed strong phytotoxic activity on R. sativus seedlings, indicating its potential use as a natural bio-herbicide in agriculture. The results showed that the effect associated to local edaphoclimatic conditions not only impacted on the quality and quantity of the essential oil, but also on the industrial uses derived from its biological activities.

Study of the Analgesic Potential of the Ethanolic Extract of Moroccan Cistus ladanifer L

AIMS

The study aimed to analyze the analgesic activity of Cistus ladanifer L.

BACKGROUND

Cistus ladanifer L. is a fragrant shrub of the Cistaceae family widespread in the Mediterranean basin, it has various biological activities, including antidiabetic and antihypertensive effects.

OBJECTIVES

The objective of this work was to study the phytochemical profile, the acute toxicity and the analgesic power of the ethanolic extract of the species Cistus ladanifer L. (C. ladanifer) collected in Northern Morocco.

METHODS

The evaluation of antinociceptive activity in mice was performed using two validated models, the formalin-induced paw-licking model and the acetic acid-provoked writhing test.

RESULTS

According to the results, five phenolic compounds were identified in the ethanolic extract by HPLC-MS/MS. As regards the acute toxicity study, the results showed no mortality or clinical symptoms in mice treated to compare the control group at doses up to 5,000 mg/kg BW. Regarding the analgesic effect, the ethanolic extract at the doses of 400 and 800 mg/kg, BW showed a statistically significant (p <0.05) and dose-dependent analgesic effect in two nociceptive tests. On the other hand, in the syrup of ethanolic extract at the dose of 800 mg/kg, BW expressed the most superior pain-inhibiting effect in both tests, producing an analgesic effect equivalent to that of the reference drug (indomethacin).

CONCLUSION

These findings provide pharmacological justification that might aid in the development of a natural anti-nociceptive medication as an alternative to chemical analgesic drugs.

Phytochemistry and Antihyperglycemic Potential of Cistus salviifolius L., Cistaceae

Cistus salviifolius has been previously reported as a traditional remedy for hyperglycemia. However, the plant has been scarcely investigated from scientific point of view. Thus, the aim was to examine the chemical composition and to evaluate its antioxidant and antihyperglycemic potential in vitro. Aqueous and ethanolic extracts were evaluated for total phenolic, tannin, and flavonoid content using spectrophotometric methods. Detailed chemical characterization was performed by high-performance liquid chromatography (HPLC-DAD). The volatile organic compounds (VOCs) profile was assessed by gas chromatography technique. The potential in diabetes treatment was evaluated through tests of free radicals neutralization, inhibition of lipid peroxidation process, and test of ferric ion reduction; activity in tests of inhibition of α-amylase, α-glucosidase and dipeptidyl peptidase-4 was also evaluated. High content of phenolics (majority being tannins) was detected; detailed HPLC analysis revealed high content of gallic acid, followed by rutin, chlorogenic and caffeic acids. The VOCs analysis determined sesquiterpene hydrocarbons and oxygenated sesquiterpenes as the main groups of compounds. The assays classified extracts as potent neutralizers of 2,2-diphenyl-1-picrylhydrazil and nitroso radicals formation and potent inhibitors of α-amylase and α-glucosidase. In conclusion, Cistus salviifolius represents a rich source of phenolics and essential oil with sesquiterpenes. The established results suggested its promising antioxidant and antihyperglycemic activities.

The use of Dalmatian pyrethrum daisy and an excipient in the treatment of seborrheic dermatitis

The active ingredients of the Pyretrin-D trichological cosmetic series, namely benzyl benzoate, Dalmatian pyrethrum daisy, Cistus incanus, tea tree oil and geranium oil, almond acid and arginine were tested in respect to the treatment of seborrheic dermatitis. The paper describes the application of Dalmatian pyrethrum daisy and the excipient. Methods and devices used to confirm the effectiveness of the tested formulations included the TrichoScope Polarizer Dino-Lite (MEDL4HM) and the scanning electron microscope (SEM).

Chemical and Bioactive Characterization of the Essential Oils Obtained from Three Mediterranean Plants

Cupressus sempervirens L., Juniperus communis L. and Cistus ladanifer L. are Mediterranean arboreal and shrub species that possess essential oils (EO) in their leaves and branches. This study aimed at characterizing the EOs obtained by steam distillation from the three species collected in different locations from Spain (Almazán, Andévalo, Barriomartín, Cerezal, Ermitas and Huéscar). For this purpose, volatiles composition was determined by GC-MS, and different bioactivities were evaluated. The highest content in terpenes was observed in C. sempervirens (Huéscar origin) followed by J. communis (Almazán origin), corresponding to 92% and 91.9% of total compounds, respectively. With exception of C. ladanifer from Cerezal that presented viridiflorol as the most abundant compound, all the three species presented in common the α-pinene as the major compound. The EOs from C. ladanifer showed high antibacterial potential, presenting MIC values from 0.3 to 1.25 mg/mL. Concerning other bioactivities, C. ladanifer EO revealed an oxidation inhibition of 83%, while J. communis showed cytotoxicity in the MCF-7 cell line, and C. sempervirens and C. ladanifer EOs exhibited the highest potential on NCI-H460 cell lines. Nevertheless, some EOs revealed toxicity against non-tumoral cells but generally presented a GI₅₀ value higher than that of the tumor cell lines.

The antimicrobial capacity of Cistus salviifolius and Punica granatum plant extracts against clinical pathogens is related to their polyphenolic composition

Antimicrobial resistance poses a serious threat to human health worldwide. Plant compounds may help to overcome antibiotic resistance due to their potential resistance modifying capacity. Several botanical extracts and pure polyphenolic compounds were screened against a panel of eleven bacterial isolates with clinical relevance. The two best performing agents, Cistus salviifolius (CS) and Punica granatum (GP) extracts, were tested against 100 Staphylococcus aureus clinical isolates, which resulted in average MIC50 values ranging between 50-80 µg/mL. CS extract, containing hydrolyzable tannins and flavonoids such as myricetin and quercetin derivatives, demonstrated higher activity against methicillin-resistant S. aureus isolates. GP extract, which contained mostly hydrolyzable tannins, such as punicalin and punicalagin, was more effective against methicillin-sensitive S. aureus isolates. Generalized linear model regression and multiple correspondence statistical analysis revealed a correlation between a higher susceptibility to CS extract with bacterial resistance to beta-lactam antibiotics and quinolones. On the contrary, susceptibility to GP extract was related with bacteria sensitive to quinolones and oxacillin. Bacterial susceptibility to GP and CS extracts was linked to a resistance profile based on cell wall disruption mechanism. In conclusion, a differential antibacterial activity against S. aureus isolates was observed depending on antibiotic resistance profile of isolates and extract polyphenolic composition, which may lead to development of combinatorial therapies including antibiotics and botanical extracts.

Evaluation of antidiabetic effect of Cistus salviifolius L. (Cistaceae) in streptozotocin-nicotinamide induced diabetic mice

Objectives Cistus salviifoluis L. is a shrub from Cistaceae family used in many traditional medicines for the treatment of various diseases including diabetes mellitus. The aim of this study was to evaluate the in vivo antidiabetic potential of the aerial parts aqueous extract of Cistus salviifolius L. (CSA). Methods Experimental diabetes was induced in adult male mice by intra-peritoneal injection of Streptozotocin-nicotinamide (STZ-NC). CSA at a dose of 500 mg/kg was administered daily to the diabetic mice for four weeks. The effect of the extract on hyperglycemia, body weight, serum total cholesterol, triglycerides, hepatic and renal functional markers were determined. Histopathological examination of the mice pancreas was also performed. The diabetic animals treated with CSA were compared with animals treated by the standard drug metformin. Results Treatment with CSA showed a significant reduction in blood glucose, total triglycerides and creatinine levels and prevented the reduction of body weight caused by diabetes. Furthermore, histopathological analysis of the mice pancreas showed that the group treated with CSA reduced damage induced by STZ-NC on islets of Langerhans cells when compared to the diabetic control. Conclusions The results suggest that the aqueous extract of Moroccan C. salviifolius L. possesses beneficial effect on treatment of diabetes.

The old pharmaceutical oleoresin labdanum of Cistus creticus L. exerts pronounced in vitro anti-dengue virus activity

ETHNOPHARMACOLOGICAL RELEVANCE

The haemorrhagic dengue fever affects up to 500 million patients, annually causing 20.000 deaths, with no chemotherapeutic agent available. The oleoresin labdanum of Cistus creticus L. has been established as an anti-infective agent since antiquity in Mediterranean ethnopharmacology.

MATERIALS AND METHODS

We tested several extracts and fractions of labdanum - standardised on labdane-type diterpenes via GC-MS - on their activity against the dengue virus (DENV-2 strain 00st-22A) in in vitro Vero cell cultures (96-well-plates, 5 days). Preliminary experiments with a labdanum diethyl ether raw-extract did not yield measureable results due to cytotoxic effects against Vero cells. In all following experiments, cell viability was constantly checked using the MTT-test. Fractionation of this raw-extract by liquid-liquid-extraction and column-chromatography on silica-gel (gradient elution with hexane, EtOAc, CHCl₃, MeOH) succeeded in separating the anti-viral activity of labdanum from its cytotoxic effect.

RESULTS

In the most active fraction GS5 at 30 μg/ml, dengue virus proliferation was 100% suppressed and cell viability was over 90%. Structural elucidation of major constituents of GS5 is currently ongoing, but thin-layer chromatography showed that this fraction is mainly dominated by manoyloxides, a class of labdane-type diterpenes with known antimicrobial activity. Claims concerning the antiviral activity of above ground parts of C. creticus have been made previously, but these generally ascribe this activity to hot water soluble polyphenols and propose an unspecific tanning effect of the viral surface proteins as the mechanism of action. However, the water soluble fraction enhanced viral proliferation.

CONCLUSION

We therefore describe a direct, pharmacological, antiviral activity of a diethyl ether extract of labdanum against a virulent haemorrhagic fever like dengue for the first time.

Influence of Drying Method on Some Bioactive Compounds and the Composition of Volatile Components in Dried Pink Rock Rose (Cistus creticus L.)

This study investigates the effects of various drying methods applied to leaves of Cistus creticus L. on the contents of polyphenols and the composition of the volatile fraction. The following four drying methods were used: convection drying at a temperature of 40 °C (CD 40 °C), 50 °C (CD 50 °C), and 60 °C (CD 60 °C); vacuum-microwave (VMD 240 W); combined drying, involving convection pre-drying (50 °C) and vacuum-microwave (240 W) finish drying (CPD-VMFD) as well as freeze-drying (FD). Polyphenols in the dried leaves were determined using chromatography-photodiode detector-quadrupole/time of flight-mass spectrometry (UPLC-PDA-Q/TOF-MS). The contents of odoriferous substances in the dry material were determined by means of head space-solid phase microextraction (HS-SPME) with the use of a gas chromatograph (GC). Thirty-seven polyphenol components including 21 flavonols, eight flavan-3-ols, and eight hydrolyzed tannins in dry Pink Rock Rose material were found for the first time. The highest contents of polyphenols, totaling 2.8 g 100 g⁻¹ dry matter (d.m.), were found in the samples subjected to the CPD/VMFD drying method. Pink Rock Rose subjected to this drying method was characterized by large quantities of odoriferous compounds, mainly eugenol, thymol, and carvacrol, which contribute to its antiseptic properties. By using CPD/VMFD methods, it is possible to obtain fine quality dry material from the leaves of C. creticus.

Stability and anti-proliferative properties of biologically active compounds extracted from Cistus L. after sterilization treatments

The growing interest of oncologists in natural compounds such as polyphenols and flavonoids is encouraging the development of innovative and efficient carriers for the delivery of those drugs. This study examines carboxymethyl chitosan-based microcapsules created by spray drying as a method for delivering biologically active compounds isolated from the Cistus herb. Effects of sterilization and encapsulation on the polyphenol and flavonoid content of Cistus extract were investigated to optimize the production process. Furthermore, in vitro studies were carried out to examine the anticancer properties of sterilized polyphenols and flavonoids on glioblastoma cells isolated from oncological patients. Acquired results show high anticancer potential towards glioblastoma as well as low cytotoxicity towards non-cancer cell lines by the substances in question. Steam sterilization is shown to affect the content of biologically active compounds the least. We demonstrate that the investigated form of drug encapsulation is both efficient and potentially possible to scale up from the viewpoint of the pharmaceutical industry.

Seasonal and Diurnal Variation in Leaf Phenolics of Three Medicinal Mediterranean Wild Species: What Is the Best Harvesting Moment to Obtain the Richest and the Most Antioxidant Extracts?

Mediterranean plants biosynthesize high amounts of polyphenols, which are important health-promoting compounds. Leaf polyphenolic composition changes according to environmental conditions. Therefore, it is crucial to know the temporal variation in their production. This study aimed to: i) evaluate the monthly and daily changes in polyphenols of Phyllirea latifolia, Cistus incanus, and Pistacia lentiscus to identify their best harvesting moment, ii) verify the possible correlations between phenolic production and temperature and irradiation, iii) evaluate their antioxidant capacity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical (OH)scavenging assays. The extracts of leaves harvested at 8:00, 13:00 and 18:00, in May, July, and October for two years were analysed by HPLC-DAD. Both "month" and "time of the day" affected the polyphenolic content in all species. July at 13:00 was the best harvesting moment for all polyphenolic classes of P. latifolia and only for some classes of C. incanus and P. lentiscus. Environmental parameters positively correlated with the polyphenols of C. incanus and P. latifolia, while the antioxidant capacity only varied in this last species, reaching the highest value in July. Results of the study allow to determine the balsamic time for each species. Moreover, the relationship between polyphenols and environmental data can be useful for the cultivation of these plants under controlled conditions.

Labdanum and Labdanes of Cistus creticus and C. ladanifer: Anti-Borrelia activity and its phytochemical profiling✰

BACKGROUND

Intrigued by testimonies of Saxon borreliosis self-help groups concerning considerabl improvements of their symptoms by ingestion of Cistus creticus L. (Cistaceae) leaf preparations, we recently reported on the growth inhibiting activity of extracts with different polarities and its volatile oil against Borrelia burgdorferi sensu stricto (Bbss) in vitro, determined by a bioassay guided procedure. The most active volatile oil (only about 0.10% in leaves) was found to be dominated by labdane-type manoyloxides as well as carvacrol, determined via GC-MS.

HYPOTHESIS

These terpenes are major active constituents of the old pharmaceutical oleoresin labdanum, which is secreted from the leaf surface of C. creticus and traditionally harvested, e.g., on Crete by brushing the shrubs.

METHODS

In order to elucidate the definite anti-Borrelia active principles of C. creticus, preparative scale separation of the diethyl‑ether soluble fraction of Cretan labdanum was achieved by combined silica gel 60-and RP-18 CC and analysed by novel TLC-Extractor/ES-MS as well as by 1d/2d-1H/13C-NMR data. For the antispirochaetal activity tests against Bbss in vitro, all samples were solubilised in water with addition of polysorbate 80, the effect of which on bacterial growth was examined and found to be negligible.

RESULTS

This led to isolation and identification of the monoterpene carvacrol as well as of the four major manoyloxides manoyloxide (A), 3-acetoxy-manoyloxide (B), 3‑hydroxy-manoyloxide (C), and epi‑manoyloxide (D). Additionally, 2-keto-manoyloxide (E) and sclareol (F) were identified via GC/EI-MS. In subsequent microbiological tests of the isolated compounds, epi‑manoyloxide (D) exhibited by far the strongest individual antispirochaetal effect, equal to the positive control amoxicilline. Furthermore, manoyloxide (A), carvacrol, and the diethyl‑ether soluble fraction of labdanum as a whole contribute to the strong antispirochaetal activity, while the other labdanes were less active. Isolated manoyloxides were further used as external standards for a GC-MS screening of labdanum samples from different origins, revealing exceptionally high contents of all analysed manoyloxides in the samples of Cretan labdanum from C. creticus, while their contents in other commercial available labdanum samples were lower by several orders of magnitude. Especially in Spanish labdanum samples, declared as Cistus ladanifer L., mainly simple alkanes and at most traces of epi‑manoyloxide (D) and of manoyloxide (A) could be detected.

CONCLUSION

The application of C. creticus preparations by Lyme disease self-help groups may be considered as a reasonable therapy approach. For the first time, isolated epi‑manoyloxide and carvacrol could be evaluated as most promising candidates for drug development and labdanum based phytomedicine development, respectively. They should serve as vital active markers for quality assessments of C. creticus preparations.

Unraveling the crucial role of the ascorbate-glutathione cycle in the resilience of Cistus monspeliensis L. to withstand high As concentrations

Cistus monspeliensis L. is a species that grows spontaneously in contaminated mining areas of the Iberian Pyrite Belt. This species can accumulate high concentrations of As in the shoots without visible signs of phytotoxicity. In order to understand the physiological mechanisms underlying this tolerance, C. monspeliensis was grown in an Arenosol irrigated with aqueous nutrient solutions containing increasing concentrations of As (0, 1500, 5000, 10000, 15000 µM) and the effects of this metalloid on plant development and on the defence mechanisms against oxidative stress were monitored. Independently of the treatment, As was mainly retained in the roots. The plants with the highest concentrations of As in the shoots (> 5000 µM) showed toxicity symptoms such as chlorosis, low leaf size and decrease in biomass production and also nutritional deficiencies. Most of the studied physiological parameters (pigments, glutathione, ascorbate and antioxidative enzymes) showed significant correlation with As concentration in roots and shoots. Pigments, especially anthocyanins, were negatively affected even in the treatments with the lowest As concentrations. Glutathione increased significantly in roots at low As levels while in shoots this increase occurred in all As treatments. Ascorbate decreased in both tissues with As addition. The highest concentrations of As in shoots of C. monspeliensis triggered defence mechanisms against oxidative stress, namely by inducing the expression of genes coding antioxidative enzymes.

Mediterranean herb extracts inhibit microbial growth of representative oral microorganisms and biofilm formation of Streptococcus mutans

In light of the growing antibiotic resistance, the usage of plant-derived antimicrobial agents could serve as an effective alternative treatment against oral infections. The aim of this study was to investigate the antimicrobial and antibiofilm activity of Mediterranean herb extracts against representative oral microorganisms. The extraction procedures and the analysis of the obtained extracts were performed under established experimental conditions. The minimum inhibitory (MIC) and bactericidal (MBC) concentrations of the methanol extracts of Cistus creticus ssp. creticus, Cistus monspeliensis, Origanum vulgare, Rosmarinus officinalis, Salvia sclarea and Thymus longicaulis against eight typical oral bacteria and the fungus Candida albicans were determined. The antibiofilm activity against Streptococcus mutans was also quantified using the microtiter plate test. Overall, all tested extracts inhibited effectively the screened obligate anaerobic microorganisms and in concentrations ≥0.3 mg ml-1 had moderate to high antibiofilm activity comparable to that of chlorhexidine (CHX) against S. mutans. In particular, R. officinalis (MIC: 0.08-5.00 mg ml-1) and S. sclarea (MIC: 0.08-2.50 mg ml-1) showed the highest antibacterial activity, while Cistus spp., R. officinalis and S. sclarea significantly inhibited S. mutans biofilm formation at 0.60, 1.25 and 2.50 mg ml-1, respectively. Porphyromonas gingivalis and Parvimonas micra were high susceptible to O. vulgare (MIC = 0.30 mg ml-1), whereas T. longicaulis eradicated all oral bacteria (MBC: 0.15-2.50 mg ml-1). Nevertheless, C. albicans showed no sensitivity to the tested extracts. In conclusion, the tested plant extracts could serve as alternative natural antibacterial and antibiofilm components against oral infections.

Neglected Mediterranean plant species are valuable resources: the example of Cistus ladanifer

The combination of genotypic selection, targeted and improved cultivation, and processing techniques for specific applications gives C. ladanifer the potential to be used as a valuable resource in Mediterranean areas with poor agronomic advantages. Cistus ladanifer (rockrose) is a perennial shrub, well adapted to the Mediterranean climate and possibly to upcoming environmental changes. As a sequence to a thorough review on taxonomic, morphological, chemical and competitive aspects of C. ladanifer, the research team focuses here on the economic potential of C. ladanifer: from production to applications, highlighting also known biological activities of extracts and their compounds. The use of this natural resource may be a viable solution for poor and contaminated soils with no need for large agricultural techniques, because this species is highly resistant to pests, diseases and extreme environmental factors. In addition, this species reveals interesting aptitudes that can be applied to food, pharmaceutical, phytochemical and biofuel industries. The final synthesis highlights research lines toward the exploitation of this neglected resource, such as selection of plant lines for specific applications and development of agronomic and processing techniques.

Soil Perturbation in Mediterranean Ecosystems Reflected by Differences in Free-Lipid Biomarker Assemblages

Environmental information provided by free lipids in soil samples collected from control and disturbed plots (Madrid, Spain) was assessed by comparing molecular assemblages of terpenoids and distribution patterns of alkanes and fatty acids (FAs) analyzed by gas chromatography-mass spectrometry (GC-MS). Wildfires in pine forests led to increased proportions of retene, dehydroabietin, and simonellite. Friedo-oleananes were characteristic in soils under angiosperms, and norambreinolide-type diterpenes were characteristic in soils encroached by Cistus bushes. Steroids were major compounds in pastured sites. Enhanced Shannon's lipid biodiversity index in disturbed soils compared with in control soils suggested patterns of recent lipids overlapping a preserved original lipid signature. The extent of the environmental impacts was illustrated as Euclidean distances between paired control and disturbed sites calculated using the compounds in alkyl homologous series as descriptors. As expected, reforestation, bush encroachment, wildfires, and cultivation were reflected by changes in the molecular record of lipids in soils.

[Cistus - queen of teas]

The aim of our article is to present a healthy qualities of Cistus. Cistus is plant belonging to the Cistaceae has strong health-promoting properties through its antioxidant, immunomodulatory, bacteriostatic and antifungal activities. Cistus has an inhibitory effect on the multiplication of viruses, which can be used to treat cold and influenza. A significant effect of the Cistus on stopping the growth and proliferation of prostatic cells was also demonstrated, which evidence of cytotoxic and antiproliferative activity. This activity can be used in both benign and malignant prostatic enlargement, as well as adjuvant in the treatment of other cancers. Extract from Cistus through modulation of immune system significantly strengthens immunity and has antiallergic activity. Cistus has a lot of polyphenols that destroy free radicals, inhibit the formation and development of inflammation in the body, strengthen, energize, and have a preventive effect on cardiovascular diseases. Through bioflavonoids, it works synergistically with vitamin C, enhancing its action, and also protects the mucous membrane of the stomach, preventing the formation of ulcers, or helping to treat them. Because of healing properties, as well as taste qualities the Cistus- teacan be boldly recommended as a daily drink for both young and old people. The promoting the use of infusion from a Cistus along with honey or lemon juice should be as wide as possible.

Cistus ladanifer (Cistaceae): a natural resource in Mediterranean-type ecosystems

Cistus ladanifer has a well-defined taxonomic identity. 2,2,6-trimethylcyclohexanone may be an authenticity and taxonomic marker. Its traits and applications make it a possible economic resource fitted for Mediterranean areas. Cistus ladanifer is a dominant shrub species endemic to the western Mediterranean region. Due to its dominant nature and its potential ecological, aromatic or pharmacological applications, C. ladanifer has been the object of numerous studies. In this review current knowledge on different aspects of this species is summarized, from its taxonomy to its chemical characterisation or its competitive traits. There are no doubts about the taxonomic entity of C. ladanifer, although the recognition of infraspecific taxa deserves more attention. Given that the fragrant exudate of C. ladanifer holds a very specific composition, one species specific carotenoid, 2,2,6-trimethylcyclohexanone, derivative is proposed as an authenticity marker for uses of C. ladanifer in pharmacological or aromatic industries. Evidence is also gathered on the extreme adaptation of C. ladanifer to stressful conditions in the Mediterranean region, such as the ability to survive in low hydric and high solar exposition conditions, presistence in poor and contaminated soils, and growth inhibition of several other plants through the release of allelochemicals. Thus, the finding of potential applications for this plant may contribute to enhance the economic dimension of derelict lands, such as mine tailings or poor agricultural Mediterranean areas.

Dietary Effects on Stable Carbon Isotope Composition of Fatty Acids in Polar and Neutral Fractions of Intramuscular Fat of Lambs

In this study we measured δ¹³C values of the main fatty acids (FA) present in neutral and polar intramuscular lipids of meat samples from 24 lambs, fed with four different diets supplemented with sunflower and linseed oil and the tanniferous shrub Cistus ladanifer L. The objective was to understand if the increase in intramuscular fat observed in lambs fed simultaneously C. ladanifer and oil was explained mostly by incorporation of diet derived FA or by increased de novo FA synthesis. De novo FA synthesis was evaluated by ¹³C enrichment (‰) of 16:0 in intramuscular lipids compared to bulk diet or compared to dietary 16:0. Oil reduced ¹³C enrichment of 16:0 in muscle lipid but had no effect when the diet included C. ladanifer (P value <0.01). Thus, dietary C. ladanifer blocked the inhibitory effects of lipid supplementation on de novo FA synthesis.

The flavonol-enriched Cistus albidus chloroform extract possesses in vivo anti-inflammatory and anti-nociceptive activity

ETHNOPHARMACOLOGICAL RELEVANCE

Cistus albidus L. (Cistaceae) has been traditionally used to treat various inflammatory diseases, but no systematic studies on the anti-inflammatory and anti-nociceptive actions of C. albidus and its putative mechanism have been reported. We aimed to explore the anti-inflammatory and anti-nociceptive effects of this plant and to characterize its polyphenolic composition by liquid chromatography coupled to mass spectrometry (MS).

MATERIALS AND METHODS

A chloroform extract derived from C. albidus leaves was obtained by solid-liquid and liquid-liquid extraction. The tail immersion test and acetic-acid-induced writhing test were used to evaluate the anti-nociceptive action, while the experimental λ-carrageenan-induced paw edema model was used to test the anti-inflammatory action. Changes in cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) expression, as well as the role of mitogen-activated protein kinases (MAPKs) and the nuclear transcription factor kappa B (NF-kB) signaling pathways on lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages were analyzed by western blotting. HPLC with diode array detection coupled to tandem mass spectrometry detection with electrospray ionization (HPLC-DAD-ESI-MS/MS) was performed to determine the phytochemical profile of the extract.

RESULTS

Significant anti-nociceptive activity was observed both in the tail immersion (59.63% reduction at 120min) and in the acetic acid (65.94% inhibition) tests at 100mg/kg. The extract (50mg/kg) exhibited a substantial reduction in paw edema (51.6%) and significantly inhibited nitrite generation (72.62%) without affecting cell viability of LPS-stimulated murine peritoneal macrophages. These results were concomitant with a down-regulation of the pro-inflammatory enzymes COX-2 and iNOS in extract-treated macrophages and a decrease in p38 MAPK phosphorylation. HPLC-DAD-ESI-MS/MS analysis revealed that flavonols such as kaempferol and quercetin derivatives were potentially responsible for such effects.

CONCLUSION

These results support the widespread use of C. albidus in popular medicine and indicate that this plant has therapeutic potential with analgesic and anti-inflammatory properties based on the presence of flavonol derivatives.

Acute and sub-chronic toxicity studies of the aqueous extract from leaves of Cistus ladaniferus L. in mice and rats

ETHNOPHARMACOLOGICAL RELEVANCE

Cistus ladaniferus L. (C.ladaniferus) (Cistaceae) is an aromatic shrub native to the Mediterranean region. The leaves are widely used in traditional medicine throughout Morocco for the treatment of various diseases including, diabetes, diarrhea, inflammation, and skin ailments. However, to the best of our knowledge, no systematic study concerning its toxicity profile has been reported.

AIM OF THE STUDY

The study carried out evaluates the potential toxicity of the aqueous extract from leaves of the C.ladaniferus (CL extract) shrub, through the method of acute and sub-chronic oral administration in mice and rats.

MATERIALS AND METHODS

During the acute toxicity study, male and female mice were orally administrated with CL aqueous extract at single doses of 500, 1000, 2000, 3000 and 5000mg/kg (n = 5/group/sex). Abnormal behavior, toxic symptoms, weight, and death were observed for 14 consecutive days to assess the acute toxicity. During the sub-chronic toxicity study, the aqueous extract was administered orally at doses of 500, 700 and 1000mg/kg (n = 6/group) daily to Wistar rats of both sexes for 90 days. The general behavior of the rats was observed daily, and their body weight was recorded weekly. A urinalysis, biochemical analysis, hematological analysis, macroscopic examination and histopathological examination of several organs were conducted at the end of the treatment period.

RESULTS

During the acute toxicity test, when mice were administered doses of 3000 and 5000mg/kg, the CL extract produced a 10-30% mortality rate, respectively, and induced signs of toxicity. However, no mortality or adverse effect was noted at the doses of 1000 and 2000mg/kg. The median lethal dose (LD50) of the extract was estimated to be more than 5000mg/kg. In the subchronic study, the CL extract induced no mortality or treatment-related adverse effects with regard to body weight, general behavior, relative organ weights, urine, hematological, and biochemical parameters. Histopathological examination of vital organs showed normal architecture suggesting no morphological alterations. Moreover, the CL extracts improved lipid profile and exhibited a significant hypoglycemic effect in all doses tested in rats.

CONCLUSION

The results of the present study suggest that treatment with the CL extract for 13 weeks does not appear to produce significant toxicity, except at high dose. Therefore, the use of appropriate levels of the CL extract as a traditional medicine remedies should have a wide margin of safety for its therapeutic use.

ANTIOXIDANT AND CANCER CHEMOPREVENTIVE ACTIVITIES OF CISTUS AND POMEGRANATE POLYPHENOLS

Polyphenol rich extracts obtained from cistus herb (Cistus incanus L.) and pomegranate peel (Punica granatum L.) exhibited significant antioxidant activity in V79 cell culture (Chinese hamster lung fibroblasts) -cistus extract reduced intracellular content of reactive oxygen species (ROS) by 30-40% and pomegranate extract by 29-36%. In human breast (MCF-7) and colon (LOVO) cancer cell lines cistus and pomegranate extracts decreased cancer cell growth both in drug-sensitive cells by 15-30% and in drug resistant (doxorubicin-resistant; DX) sublines by 5-20%. However, the extracts did not influence on cell growth%f normal hamster fibroblast cultures (V79). The extracts induced apoptosis in the tested cancer cell lines. Significantly higher proapoptotic impact of the extracts was observed in drug-sensitive than in drug-resistant sublines. The results suggest potential usefulness of the tested polyphenol rich extracts in people exposed to oxidative stress. Their potential use as adjuvant therapy of human cancers needs further studies.

CONDITIONS OF PROOXIDANT ACTIVITY OF CISTUS AND POMEGRANATE POLYPHENOLS IN V79 CELL CULTURES

Polyphenol rich extracts obtained from cistus herb (Cistus incanus L.) and pomegranate peels (Punica granatunm L.) added at high concentrations (25-100 pg/mL) to V79 (Chinese hamster lung fibroblast) cell cultures, markedly increased intracellular level of ROS (reactive oxygen species). Also in cells exposed to the exogenous oxidant - H₂0₂, [100 μM, 30 min., 37'C] intracellular ROS level was augmented, although to a lower extent than in resting cells not exposed to H₂0₂. Additionally, cistus and pomegranate extracts at high concentration (25-100 μg/mL) inhibited the P-gp protein efflux function in V79 cell cultures. Both pro-oxidant activity of polyphenols at high concentrations and their ability to decrease efflux function of P-gp (cellular multidrug resistance protein) could be exploited for improving anticancer adjuvant therapy.

Use of Cistus aqueous extracts as botanical fungicides in the control of Citrus sour rot

In this work, we investigated the in vitro and in vivo antifungal activity of aqueous extracts obtained from eight Cistus plant species against the development of Geotrichum citri-aurantii, the causal agent of citrus sour rot. The results demonstrate the in vitro effectiveness of all tested Cistus species aqueous extracts against G. citri-aurantii, the inhibition of mycelial growth ranged between 80 and 100%. Furthermore, Cistus aqueous extracts totally inhibited germination of G. citri-aurantii arthrospores at a concentration of 5 mg/mL. Among the plant species tested, C. laurifolius, C. salviifolius, C. monspeliensis, C. ladanifer and C. populifolius displayed the best fungistatic activity since the minimum inhibitory concentration (MIC) was <0.625 mg/mL. Under in vivo conditions, incidence of sour rot was lowered to 8.33% when fruits were treated with aqueous extracts of C. populifolius and C. creticus compared to 100% in the control. Disease severity was lowered to 3.74, 4.47 and 5.13% when fruits were treated with C. creticus, C. ladanifer and C. populifolius aqueous extracts, respectively. Using such these biopesticides in a replacement for synthetic fungicides or in combination with other established disease management practices could help control citrus postharvest decay in a more sustainable and eco-friendly way.

Vibrational and Thermal Studies of Essential Oils Derived from Cistus ladanifer and Erica arborea Shrubs

Essential oils from the two most representative shrub species from the Iberian Peninsula (namely Cistus ladanifer L. and Erica arborea L.) have been characterized by Fourier transform infrared spectroscopy (FTIR) and thermoanalytical techniques (TG/DTG and DSC). Vibrational spectra have been compared with those of components of the plants, and with those of oils, gums and resins from other species. The different content in terpenoids of C. ladanifer oil (mainly mono- and- sesquiterpenoids) and E. arborea oil (mainly triterpenoids) is reflected in the ATR-FTIR by the position of the bands at around 2873 cmf⁻¹, 1730 cm-⁻¹ and 1678 cm⁻¹ As regards their thermal behavior, C. ladanifer-derived oil evinced higher thermal stability than that of obtained from E arborea: the pyrolysis of the former was sensitized at 210°C, whereas for the later it occurred at 143°C. These temperatures are high enough to state that thermolabile constituents such as terpenoids are conserved in the hydrodistillation and that this extraction process ensures the recovery of the main constituents of both-essential oils.

Modulation of in vitro rumen biohydrogenation by Cistus ladanifer tannins compared with other tannin sources

BACKGROUND

Tannins are polyphenolic compounds able to modify the ruminal biohydrogenation (BH) of unsaturated fatty acids, but their activity may vary among different tannin sources. The effect of rockrose (Cistus ladanifer) on BH has never been compared with other more common tannin sources. Tannin extracts (100 g kg^-1 substrate dry matter) from chestnut (CH), quebracho (QB), grape seed (GS) and rockrose (CL) were incubated in vitro for 6 h with ruminal fluid using as substrate a feed containing 60 g kg^-1 of sunflower oil. A control treatment with no added tannins was also included.

RESULTS

Compared with the control, GS and CL, but not CH and QB, increased (P < 0.05) the disappearance of c9,c12-18:2 with a consequent larger production of c9,t11-18:2 and t11-18:1. However, no differences among treatments (P > 0.05) were observed for the disappearance of c9-18:1 and c9,c12,c15-18:3. The production of 18:0 was not different (P > 0.05) among treatments, although its proportion in the total BH products was lower (P < 0.05) for GS than for the other treatments.

CONCLUSION

Condensed tannins from GS and, to a lesser extent, from CL stimulate the first steps of BH, without a clear inhibition of 18:0 production. © 2016 Society of Chemical Industry.

Characterisation and Antioxidant Activity of Crude Extract and Polyphenolic Rich Fractions from C. incanus Leaves

Cistus incanus (Cistaceae) is a Mediterranean evergreen shrub. Cistus incanus herbal teas have been used as a general remedy in traditional medicine since ancient times. Recent studies on the antioxidant properties of its aqueous extracts have indicated polyphenols to be the most active compounds. However, a whole chemical characterisation of polyphenolic compounds in leaves of Cistus incanus (C. incanus) is still lacking. Moreover, limited data is available on the contribution of different polyphenolic compounds towards the total antioxidant capacity of its extracts. The purpose of this study was to characterise the major polyphenolic compounds present in a crude ethanolic leaf extract (CEE) of C. incanus and develop a method for their fractionation. Superoxide anion, hydroxyl and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assays were also performed to evaluate the antioxidant properties of the obtained fractions. Three different polyphenolic enriched extracts, namely EAC (Ethyl Acetate Fraction), AF1 and AF2 (Aqueos Fractions), were obtained from CEE. Our results indicated that the EAC, enriched in flavonols, exhibited a higher antiradical activity compared to the tannin enriched fractions (AF1 and AF2). These findings provide new perspectives for the use of the EAC as a source of antioxidant compounds with potential uses in pharmaceutical preparations.

Quantitative Variation of Flavonoids and Diterpenes in Leaves and Stems of Cistus ladanifer L. at Different Ages

The compounds derived from secondary metabolism in plants perform a variety of ecological functions, providing the plant with resistance to biotic and abiotic factors. The basal levels of these metabolites for each organ, tissue or cell type depend on the development stage of the plant and they may be modified as a response to biotic and/or abiotic stress. As a consequence, the resistance state of a plant may vary in space and time. The secondary metabolites of Cistus ladanifer have been quantified in leaves and stems throughout autumn, winter, spring and summer, and at different ages of the plant. This study shows that there are significant differences between young leaves, mature leaves and stems, and between individuals of different ages. Young leaves show significantly greater synthesis of flavonoids and diterpenes than mature leaves and stems, with a clear seasonal variation, and the differences between leaves at different growth stages and stems is maintained during the quantified seasons. With respect to age, specimens under one year of age secreted significantly lower amounts of compounds. The variation in the composition of secondary metabolites between different parts of the plant, the season and the variations in age may determine the interactions of Cistus ladanifer with the biotic and abiotic factors to which it is exposed.

Potent in vitro antiviral activity of Cistus incanus extract against HIV and Filoviruses targets viral envelope proteins

Novel therapeutic options are urgently needed to improve global treatment of virus infections. Herbal products with confirmed clinical safety features are attractive starting material for the identification of new antiviral activities. Here we demonstrate that Cistus incanus (Ci) herbal products inhibit human immunodeficiency virus (HIV) infections in vitro. Ci extract inhibited clinical HIV-1 and HIV-2 isolates, and, importantly, a virus isolate with multiple drug resistances, confirming broad anti-HIV activity. Antiviral activity was highly selective for virus particles, preventing primary attachment of the virus to the cell surface and viral envelope proteins from binding to heparin. Bioassay-guided fractionation indicated that Ci extract contains numerous antiviral compounds and therefore has favorably low propensity to induce virus resistance. Indeed, no resistant viruses emerged during 24 weeks of continuous propagation of the virus in the presence of Ci extracts. Finally, Ci extracts also inhibited infection by virus particles pseudotyped with Ebola and Marburg virus envelope proteins, indicating that antiviral activity of Ci extract extends to emerging viral pathogens. These results demonstrate that Ci extracts show potent and broad in vitro antiviral activity against viruses that cause life-threatening diseases in humans and are promising sources of agents that target virus particles.

The Polyphenolic Composition of Cistus incanus Herbal Tea and Its Antibacterial and Anti-adherent Activity against Streptococcus mutans

The Mediterranean plant Cistus incanus is rich in polyphenols and has shown several pharmacological activities, mainly antibacterial effects. Furthermore, in situ studies revealed that a C. incanus infusion reduces the initial bacterial adhesion in the oral cavity due to the polyphenols, an indication that C. incanus might reduce the risk of caries disease. In the present study, the polyphenols from four different commercial C. incanus herbal teas were extracted by standardized accelerated solvent extraction for in vitro tests and by an infusion for in situ tests. Both extracts were characterized qualitatively and quantitatively by high-performance liquid chromatography and only the polyphenol content differed slightly. By means of diode array detection and mass spectrometry, 29 polyphenols, including ellagitannins, flavanols, and glycosylated flavonols, were identified. Thereby, only quantitative but no qualitative differences between the four samples were detected. Furthermore, the in vitro antibacterial activity of the C. incanus accelerated solvent extracts against Streptococcus mutans, one of the primary cariogenic bacterial species, was examined using a live/dead assay (BacLight®). With this approach, C. incanus yielded antibacterial properties. Additional in situ experiments indicated that rinses with a C. incanus infusion reduced the initial bacterial colonization of enamel samples exposed to oral fluids for over eight hours. Furthermore, it was shown by transmission electron microscopy that the application of a C. incanus infusion modifies the ultrastructure of the acquired enamel pellicle, yielding a more electron-dense morphology. It can be assumed that the polyphenols are responsible for the observed effects.

Growth performance, carcass and meat quality of lambs supplemented with increasing levels of a tanniferous bush (Cistus ladanifer L.) and vegetable oils

The effects of dietary inclusion of Cistus ladanifer L. (CL) and a vegetable oil blend were evaluated on growth performance,carcass and meat quality of fifty four lambs that were assigned to 9 diets, corresponding to 3 levels of CL(50, 100 and 200 g/kg DM) and 3 levels of oil inclusion (0, 40 and 80 g/kg DM). Treatments had no effects on growth rate. Oil depressed dry matter intake (P = 0.017), carcass muscle (P = 0.041) and increased (P = 0.016) kidney knob channel fat. Chemical and physical meat quality traits were not affected by treatments. Off-flavour perception was higher for 8% of oil (P b 0.001). The level of 100 g/kg DM of CL inclusion improved meat stability after 7 days of storage. Supplementation with linseed and soybean oils (2:1) was a good approach to improve meat nutritional value from feedlot lambs, increasing total n-3 PUFA.

Influence of the leaf content and herbal particle size on the presence and extractability of quantitated phenolic compounds in Cistus incanus herbal teas

A variety of Cistus incanus products and thereof a majority of herbal teas are offered by manufacturers despite a classification as Novel Food. For a re-evaluation of this legal status, a characterization of bioactive ingredients will provide data. These teas consist of various compositions of plant parts and particle sizes. Whereas some include high leaf contents with a small particle size, others mainly consist of woody stem parts. For the consumer it is of interest which product yields the highest concentrations of bioactive phenolic compounds in the final infusions. In this study, four commercially available samples were divided into leaves and stems. Additionally, one sample was reconstituted in three mixtures of these plant parts. The amount of wood was determined by cellulose concentration. The aim was to estimate the influence of the plant parts on the concentration of phenolic compounds, which were identified by LC-DAD-ESI-MS/MS and quantitated by LC-DAD. Furthermore, one herbal tea was separated into six fractions with different particle sizes to investigate the influence of particle size on the extractability of phenolic compounds. On basis of the results, the highest concentrations of bioactive compounds in the infusions were yielded when leafy parts with a small particle size were used for brewing.

In vivo and in vitro antidiabetic effect of Cistus laurifolius L. and detection of major phenolic compounds by UPLC-TOF-MS analysis

ETHNOPHARMACOLOGICAL RELEVANCE

In Turkish folk medicine, various parts of Cistus laurifolius L. are used to treat gastric ulcer and various types of pains. Additionally the tea prepared from the leaves is used to decrease symptoms of diabetes.

MATERIALS AND METHODS

In the present study, the hypoglycemic effects of aqueous and ethanol extracts of Cistus laurifolius were investigated in normal, glucose loaded hyperglycemic and streptozocin (STZ)-induced diabetic rats. α-Glucosidase and α-amylase enzyme inhibitory effects were determined to evaluate the mechanism of action. Total phenolic content of the extracts were determined by using Folin-Ciocalteu reagent and Ultra Performance Liquid Chromatography-Time of Flight Mass Spectrometer (UPLC-TOF-MS) was used to detect the major phenolic compounds in the extract.

RESULTS

Results indicated that blood glucose levels of the STZ-induced diabetic rats were decreased by ethanol extract at of 250 and 500mg/kg doses as compared to control group (16%-34%). In glucose loaded animals, extracts have shown a weak hypoglycemic effect (11%-20%). Additionally, the ethanol extract of Cistus laurifolius is found to be a potent inhibitor of α-glucosidase and α-amylase, possibly due to several polyphenolic compounds present within the extract. Twelve major flavonoids (apigenin, quercetin, kaempferol, naringenin, quercitrin and their derivatives), gallic, ellagic and chlorogenic acid in chromatographic fingerprint were analyzed by the on-line UPLC-TOF-MS system.

CONCLUSIONS

Due to having inhibitory effect on blood glucose level and carbohydrate digesting enzymes (α-glucosidase and α-amylase), Cistus laurifolius leaves might be beneficial for diabetic patients.

Patterns of spatio-temporal distribution of winter chronic photoinhibition in leaves of three evergreen Mediterranean species with contrasting acclimation responses

High irradiance and relatively low temperature, which characterize Mediterranean winters, cause chilling stress in plants. Downregulation of photosynthetic efficiency is a mechanism that allows plants to survive these conditions. This study aims to address whether this process shows a regular spatial pattern across leaf surface or not. Three species (Buxus sempervirens, Cistus albidus and Arctostaphylos uva-ursi) with contrasting responses to winter stress were studied. During 7 days, macro and micro Fv/Fm spatial patterns were monitored by the use of chlorophyll fluorescence imaging techniques. In the field, the strongest photoinhibition was found in B. sempervirens, while there was almost no chronic photoinhibition in C. albidus. In leaves of the first species, Fv/Fm decreased from base to tip while in C. albidus it was uniform over the leaf lamina. An intermediate behavior is shown by A. uva-ursi leaves. Spatial heterogeneity distribution of Fv/Fm was found inside the leaves, resulting in greater Fv/Fm values in the inner layers than in the outer ones. Neither xanthophyll-linked downregulation of Fv/Fm nor protein remobilization were the reasons for such spatial patterns since pigment composition and nitrogen content did not reveal tip-base differences. During recovery from winter, photoinhibition changes occurred in Fv/Fm, pigments and chloroplast ultrastructure. This work shows for the first time that irrespective of physiological mechanisms responsible for development of winter photoinhibition, there is an acclimation response with strong spatio-temporal variability at leaf level in some species. This observation should be taken into account when modeling or scaling up photosynthetic responses.

Susceptibility of the multi-drug resistant strain of Enterobacter aerogenes EA289 to the terpene alcohols from Cistus ladaniferus essential oil

The essential oil (EO) of Cistus ladaniferus was separated into non polar, moderately polar and polar fractions by column chromatography. The EO and its fractions were analysed by gas chromatography in combination with retention indices [GC-(RI)] and 13C nuclear magnetic resonance (13C NMR) spectroscopy. A minimum inhibitory concentration (MIC) assay was used to evaluate their antibacterial activity against Gram-positive and Gram-negative pathogens of clinical relevance, including a multi-drug resistant (MDR) strain. The most polar fraction, constituted by mono- and sesquiterpene alcohols, strongly inhibited the growth of all tested bacteria with MIC values ranging from 0.05 to 0.8 mg/mL. More importantly, this fraction displayed high activity against the MDR strain of Enterobacter aerogenes EA289. Transmission electron microscopy (TEM) observations of the MDR bacteria treated with the terpene alcohol-rich fraction revealed cell wall distortion with an outer cytoplasmic membrane detachment. The susceptibility of the MDR strain of E. aerogenes EA289 to the polar fraction of C. ladaniferus oil suggests the possible use of these natural products to treat infections caused by highly resistant bacteria.

A systematic study of the polyphenolic composition of aqueous extracts deriving from several Cistus genus species: evolutionary relationship

INTRODUCTION

Cistaceae is a large family of shrubs widely spread over the Mediterranean area. It includes Helianthemum, Halimium and Cistus genus. Cistus genus contains approximately 20 species distributed in three subgenus. The essential oil of Cistus species has been thoroughly studied, but the polyphenolic composition of the aerial parts of the different Cistus species needs further characterisation.

OBJECTIVE

To perform a comparative analysis of the qualitative and quantitative polyphenolic composition of the aerial parts of the most commonly distributed Spanish Cistus species in order to find a relationship between chemotype and subgenus.

METHODOLOGY

Thirteen aqueous extracts derived from 10 different Cistus species were analysed by using HPLC with diode array-detection coupled to electrospray ion trap mass spectrometry technique (HPLC-DAD-ESI-MS/MS). Their major compounds were identified and ellagitannins were quantified. Principal component analysis (PCA) was performed on the most relevant compounds to find out the statistical association between chemotype and variety.

RESULTS

Three main groups of compounds were found, i.e. ellagitannins, flavonoids and phenolic acids derivatives. The polyphenolic profile was specific for each species, although the abundance of some compounds also varied depending on the soil type. Whereas C. ladanifer, C. salviifolius, C. populifolius and C. libanotis were specially rich in ellagitannins, C. clusii, C. laurifolius and C. monspeliensis contained significant amounts of flavonoids and much less ellagitannins. In contrast, C. crispus, C. incanus and C. albidus showed a polyphenolic profile mostly based on flavonoids. PCA analysis showed a strong relationship between Cistus subgenus and its chemotype based on the most relevant water-soluble polyphenolic compounds.

CONCLUSIONS

Chemical composition of the leaves' aqueous extracts from plants belonging to the Cistus genus is strongly related to their subgenus, in agreement to previous taxonomical and phylogenetic divisions. In contrast, soil and climate are less influencing factors. Leucocistus and Halimioides subgenus showed a higher content in ellagitannins. However, Cistus subgenus had higher flavonoid content.

Constituents from Cistus salvifolius (Cistaceae) activate peroxisome proliferator-activated receptor-γ but not -δ and stimulate glucose uptake by adipocytes

A number of medicinal/culinary herbs have been reported to improve glucose metabolism and to yield hypoglycemic effects in patients with diabetes. Since stimulation of insulin sensitivity appears to be a potential mechanism, peroxisome proliferator-activated receptor (PPAR) γ is a likely target molecule for small lipophilic compounds derived from endogenous metabolism and nutrition. Functionally, PPAR γ integrates the control of energy, lipid, and glucose homeostasis. In addition, PPAR δ activity is involved in energy expenditure. Therefore the aim of this study was to investigate whether PPAR γ and PPAR δ as well as the stimulation of glucose uptake is activated by botanical products. CISTUS SALVIFOLIUS (Cistaceae) has been identified as a candidate botanical in a preliminary screening of extracts from medicinal plants of Greek flora. In a bioguided approach, crude extracts, fractions and in the end purified compounds have been evaluated for PPAR γ and PPAR δ specific activities using cell-based transactivation assays. Glucose uptake was measured by nonradioactive 2-[ N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxyglucose (2-NBDG) uptake. Concerning PPAR γ several extracts induced reporter gene activity, and clear dose-response patterns (0.1-100 µg/mL) could be established in the case of the cyclohexane and dichloromethane extracts. Isolation of individual compounds from the cyclohexane extract revealed that at least 6 out of 7 compounds isolated were active with TRANS-cinnamic acid showing a clear dose-response pattern. In contrast, they were found to be inactive on PPAR δ. The same compounds, however, were also active in stimulating glucose uptake into 3T3-L1 adipocytes. In summary, the bioguided fractionation of CISTUS SALVIFOLIUS yields PPAR γ stimulating metabolites with differing chemical natures. In conclusion, PPAR γ represents a candidate molecule for the mediation of improvement of glucose metabolism by botanical/nutritional products.

Effect of grape seed extract, Cistus ladanifer L., and vegetable oil supplementation on fatty acid composition of abomasal digesta and intramuscular fat of lambs

Thirty-six lambs were used in a 6 week experiment to evaluate the effect of vegetable oil blend supplementation (0 vs 60 g/kg of dry matter (DM)) and two dietary condensed tannin sources, grape seed extract (0 vs 25 g/kg of DM) and Cistus ladanifer L. (0 vs 250 g/kg of DM), on fatty acid (FA) composition of abomasal digesta and intramuscular polar and neutral lipids. Grape seed extract did not affect the FA profile of abomasal digesta or muscle lipid fractions. C. ladanifer had a minor effect in lambs fed diets with no oil but greatly changed the abomasal and muscle FA profiles in oil-supplemented lambs. It decreased 18:0 and increased 18:1 trans-11 in abomasal digesta and increased 18:1 trans-11 and 18:2 cis-9,trans-11 (P = 0.062) in muscle neutral lipids, resulting in an important enrichment of meat 18:2 cis-9,trans-11 when compared to other oil-supplemented diets (19.2 vs 41.7 mg/100 g of muscle).

High-performance liquid chromatography with diode array detection coupled to electrospray time-of-flight and ion-trap tandem mass spectrometry to identify phenolic compounds from a Cistus ladanifer aqueous extract

INTRODUCTION

Cistus ladanifer is an aromatic shrub that is widespread in the Mediterranean region. The labdanum exudate is used in the fragrance industry and has been characterised. However, there is not enough information about the phenolic content of the raw plant, the aerial part of it being a very rich source of bioactive compounds.

OBJECTIVE

Characterisation of the bioactive compounds of the raw plant and its aerial parts.

METHODOLOGY

High-performance liquid chromatography with diode array and electrospray ionisation mass spectrometric detection was used to carry out the comprehensive characterisation of a Cistus ladanifer shrub aqueous extract. Two different MS techniques were coupled to HPLC: time-of-flight mass spectrometry and tandem mass spectrometry.

RESULTS

Many well-known compounds present in Cistus ladanifer were characterised, such as flavonoids, phenolic acids, ellagitanins, hexahydroxydiphenoyl and derivatives, and other compounds.

CONCLUSION

The method described simultaneously separated a wide range of phenolic compounds and the proposed characterisation of the major compounds of this extract was carried out. It is important to highlight that, to our knowledge, this is the first time that a Cistus ladanifer aqueous extract from the raw plant has been characterised.

Growth inhibiting activity of volatile oil from Cistus creticus L. against Borrelia burgdorferi s.s. in vitro

Borreliosis patients from self-help groups reported considerable pain relief after ingestion of Cistus creticus leaf preparations. C. creticus leaf extracts of different polarities such as aqueous, ethyl acetate, hexane extracts as well as the volatile oil fraction obtained by steam distillation were tested for their antibacterial activity against Borrelia burgdorferi sensu stricto (Bbss) in vitro using the antibiotic amoxicilline as standard and polysorbate 80 as solubilizer for lipophilic extracts. Comparison of the four plant preparations shows that the volatile oil exerts the strongest growth inhibitory effect. Even concentrations of 0.02% (w/v) volatile oil in cultivation media reduced the total number of bacteria to 2% in comparison to a growth control after an eight-day cultivation period. While the aqueous extract did not reduce bacterial growth, incubation with hexane and ethyl acetate extracts clearly inhibited microbial growth. The main volatile components of the three active extracts tested were analyzed by GC-MS. The number of different labdane-type diterpenes as well as the total relative amount of diterpenes in the samples tested was highest in the essential oil of C. creticus. Identification of ten different volatile labdane-type diterpenes was assigned to the essential oil of C. creticus. Among these, manoyl oxide, 13-epi-manoyl oxide, 3-acetoxy-manoyl oxide and the monoterpene carvacrol were determined to be major constituents, accompanied by minor amounts of 3-hydroxy-manoyl oxide, all of which are known to exert antimicrobial activity.

Trace elements and activity of antioxidative enzymes in Cistus ladanifer L. growing on an abandoned mine area

The Mediterranean shrub Cistus ladanifer grows naturally in São Domingos (Portugal), an abandoned copper mine. High levels of trace elements in plants can generate oxidative stress increasing the activity of antioxidant enzymes. The aim of this work was to evaluate and compare As, Cu, Pb and Zn concentrations and the activity of the soluble and cell wall ionically bounded forms of the enzymes catalase, peroxidase and superoxide dismutase in leaves of C. ladanifer, collected in spring and summer, growing on São Domingos mine and on a non-contaminated area (Pomarão). São Domingos soils showed high total concentrations of As (2.6 g kg(-1)) and Pb (7.3 g kg(-1)) however the available fraction represented less than 1.5% of the total. C. ladanifer population from mine showed tolerance to Pb and Zn, which attain in leaves concentrations considered toxic for plants. The enzymatic activity of catalase, peroxidise and superoxide dismutase varied with plant populations and seasons, although with no particular trend, being specific to each trace element and enzyme cell localization. Catalase activity was evenly distributed between the soluble and ionically bounded forms, whereas the ionically bounded form of peroxidase predominated relatively to total activity, and the opposite was observed for superoxide dismutase. Spring and summer leaves from the two areas presented enzymatic activities in both fractions except to peroxidase soluble activities in leaves collected in summer. C. ladanifer enzymatic activity seems to be related with the co-existence of different stress factors (trace elements concentration, temperature, UV radiation and drought). The survival and growth of this species on contaminated mining soils is due to the presence of effective antioxidant enzyme-based defence systems.

Enhanced determination of abscisic acid (ABA) and abscisic acid glucose ester (ABA-GE) in Cistus albidus plants by liquid chromatography-mass spectrometry in tandem mode

An improved, quick and simple method for the extraction and quantification of the phytohormones (+)-abscisic acid (ABA) and its major glucose conjugate, abscisic acid glucose ester (ABA-GE) in plant samples is described. The method includes the addition of deuterium-labeled internal standards to the leaves at the beginning of the extraction for quantification, a simple extraction/centrifugation process and the injection into the liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS-MS) system in multiple reaction monitoring mode (MRM). Quality parameters of the method (detection limits, repeatability, reproducibility and linearity) have been studied. The objective of this work is to show the applicability of this method for quantifying the endogenous content of both ABA and ABA-GE in Cistus albidus plants that have been grown during an annual cycle under Mediterranean field conditions. Leaf samples from winter plants have low levels of ABA which increase in spring and summer showing two peaks that corresponded to April and August. These increases are coincident with the high temperature and solar radiation and the low RWC and RH registered along the year. On the other hand, the endogenous levels of ABA-GE increase until maximum values in July just before the ABA content reaches its highest concentration, decreasing in August and during autumn and winter. Our results suggest that the method is useful for quantifying both compounds in this plant material and represents the advantage of a short-time sample preparation with a high accuracy and viability.

Endosulfan sulfate sorption on natural organic substances

This work proposes a viable remediation method based on the use of natural organic substances (NOSs) that characterize the Mediterranean region to improve the ecological system. A series of experiments, including variable conditions, such as temperature, pH, contact time, and pesticide concentration, were performed to demonstrate the efficiency of endosulfan sulfate removal from water by NOSs. Experimental results showed that the pH and temperature of pesticide solutions negatively affect the adsorption process. The maximum adsorption capacity for a specific initial concentration of endosulfan sulfate (0.5 microg/L) was achieved with Origanum compactum (75%), followed by Cistus ladaniferus and Raphanus raphanistrum (72 and 68%, respectively). The adsorption tests gave very satisfying results and point to the possible application of these supports as a remediation technique to prevent pesticide contamination of aquatic ecosystems.

Flavonoids with anti-inflammatory and antinociceptive activity from Cistus laurifolius L. leaves through bioassay-guided procedures

Extracts obtained from the leaves and branches of various Cistus species have been used worldwide as folk remedy for the treatment of various inflammatory ailments including rheumatism and renal inflammations. Effects of the extracts and fractions from the leaves with non-woody branches of Cistus laurifolius L. (Cistaceae) were studied using two in vivo models of inflammation in mice. Model one was based on observed potent inhibitory activity against carrageenan-induced hind paw oedema and the second model used was acetic acid-induced, increased vascular permeability model. Through bioassay-guided fractionation and isolation procedures three flavonoids; 3-O-methylquercetin (1), 3,7-O-dimethylquercetin (2) and 3,7-O-dimethylkaempferol (3) were isolated as the main active ingredients from the ethanol extract. Later on, these flavonoids were shown to possess potent antinociceptive activity, which was assessed through inhibition of p-benzoquinone-induced writhing reflex. Results of the present study have clearly supported the utilization of Cistus laurifolius in Turkish traditional medicine. Subsequently, three flavonoids were shown to have strong antinociceptive and anti-inflammatory activities, per os without inducing any apparent acute toxicity as well as gastric damage.

Antimony distribution and mobility in topsoils and plants (Cytisus striatus, Cistus ladanifer and Dittrichia viscosa) from polluted Sb-mining areas in Extremadura (Spain)

A study about topsoil antimony distribution and mobility from the soils to the biomass has been afforded in three abandoned Sb mining areas located at Extremadura. Physico-chemical characteristics of the soils and total antimony levels were measured in soils and autochthonous plant species (Cytisus striatus, Cistus ladanifer and Dittrichia viscosa). Comparison with corresponding values in reference areas isolated from the mining activities is discussed. Antimony mobility in the soils was estimated by measuring the water extractable fraction; low results were obtained for the three soil areas, with no statistical differences. Plant ability to accumulate antimony was estimated by use of plant accumulation coefficients (PAC). Seasonal (spring vs. autumn) effects on the antimony content in the plant species. Cytisus striatus from Mari Rosa mine presented antimony excluder characteristics, whereas Dittrichia viscosa specimens growing in San Antonio mine showed a significant antimony bioaccumulation.

Prostaglandin inhibitory and antioxidant components of Cistus laurifolius, a Turkish medicinal plant

As Cistus laurifolius has been used traditionally to treat inflammatory and rheumatic disorders, its leaves were tested for prostaglandin (PG) inhibitory and antioxidant activities. The leaf extract showed both activities, i.e., inhibitory effect at 300 microg/ml on PGE1- and E2-induced contractions in guinea pig ileum and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect. The separation guided by the activities shown by these dual assays provided sixteen compounds, 1-16. Known compounds 1-12 and 15 were identified as 3-O-methyl quercetin (1), 3,7-O-dimethyl quercetin (2), genkwanin (3), 3,7-O-dimethyl kaempferol (4), 3,4'-O-dimethyl quercetin (5), apigenin (6), 3,4'-O-dimethyl kaempferol (7), ellagic acid (8), beta-sitosterol-3-O-beta-glucoside (9), quercetin 3-O-alpha-rhamnoside (10), 5-O-p-coumaroyl quinic acid methyl ester (11), 1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-alpha-l-rhamnopyranoxypropyl)-2-methoxyphenoxy]-1,3-propanediol (12) and 2,3-dihydro-2-(4'-alpha-l-rhamnopyranosyloxy-3'-methoxyphenyl)-3-hydroxymethyl-7-methoxy-5-benzofuranpropanol (15). New lignan glycosides 13 and 14 were determined to be olivil 9-O-beta-D-xyloside and berchemol 9-O-rhamnoside, respectively. Compound 16 was isolated as a 2:1 mixture of two diastereomers, the major one of which was determined to be (7S,8R)-dihydrodehydrodiconiferyl alcohol 9'-O-alpha-L-rhamnoside. The structures were determined by detailed 2D NMR analysis together with NOEDF and CD. PG inhibitory effect was observed in 1, 5, 10, 12 and 16 at 30 microg/ml and antioxidant activity, in 1, 2, 8, 10, 12-14 and 16.