Isoprenyl diphosphate synthases of terpenoid biosynthesis in rose-scented geranium (Pelargonium graveolens).

The essential oil of Pelargonium graveolens (rose-scented geranium), an important aromatic plant, comprising mainly mono- and sesqui-terpenes, has applications in food and cosmetic industries. This study reports the characterization of isoprenyl disphosphate synthases (IDSs) involved in P. graveolens terpene biosynthesis. The six identified PgIDSs belonged to different classes of IDSs, comprising homomeric geranyl diphosphate synthases (GPPSs; PgGPPS1 and PgGPPS2), the large subunit of heteromeric GPPS or geranylgeranyl diphosphate synthases (GGPPSs; PgGGPPS), the small subunit of heteromeric GPPS (PgGPPS.SSUI and PgGPPS.SSUII), and farnesyl diphosphate synthases (FPPS; PgFPPS).All IDSs exhibited maximal expression in glandular trichomes (GTs), the site of aroma formation, and their expression except PgGPPS.SSUII was induced upon treatment with MeJA. Functional characterization of recombinant proteins revealed that PgGPPS1, PgGGPPS and PgFPPS were active enzymes producing GPP, GGPP/GPP, and FPP respectively, whereas both PgGPPS.SSUs and PgGPPS2 were inactive. Co-expression of PgGGPPS (that exhibited bifunctional G(G)PPS activity) with PgGPPS.SSUs in bacterial expression system showed lack of interaction between the two proteins, however, PgGGPPS interacted with a phylogenetically distant Antirrhinum majus GPPS.SSU. Further, transient expression of AmGPPS.SSU in P. graveolens leaf led to a significant increase in monoterpene levels. These findings provide insight into the types of IDSs and their role in providing precursors for different terpenoid components of P. graveolens essential oil.

Silicone-geranium essential oil blend for long-term antifouling coatings.

This study explores the potential of geranium essential oil as a natural solution for combating marine biofouling, addressing the environmental concerns associated with commercial antifouling coatings. Compounds with bactericidal activities were identified by 13Carbon nuclear magnetic resonance (13C NMR). Thermogravimetric analysis (TGA) revealed minimal impact on film thermal stability, maintaining suitability for antifouling applications. The addition of essential oil induced changes in the morphology of the film and Fourier transform infrared spectroscopy (FTIR) analysis indicated that oil remained within the film. Optical microscopy showed an increase in coating porosity after immersion in a marine environment. A total of 18 bacterial colonies were isolated, with Psychrobacter adeliensis and Shewanella algidipiscicola being the predominant biofilm-forming species. The geranium essential oil-based coating demonstrated the ability to reduce the formation of Psychrobacter adeliensis biofilms and effectively inhibit macrofouling adhesion for a duration of 11 months.

Efficacy and safety of geranium-oregano-thymol formulations to control of dog tick Rhipicephalus sanguineus sensu lato under laboratory and field conditions.

The present study evaluated, in laboratory and field, the efficacy and safety of formulations of Pelargonium graveolens (geranium - G), Origanum majorana (oregano - O) commercial essential oils (EO) and thymol (T) to control of Rhipicephalus sanguineus sensu lato. In the laboratory, three formulas (A: 2% tween 80%, B: powder and C: nanoemulsion) by a mixture of these components (GOT) were prepared and evaluated, and the best one was used to assess its safety and field application against R. sanguineus s. l. on naturally infested dogs. Besides the major compounds of the EO used were identified. The results of the lab study showed that formula A (2.5 g of each G + O + T + 2% tween 80 to complete 100 mL) was significantly more effective than the other two formulas tested and exhibited highly effective adulticidal, larvicidal, and ovicidal activity against R. sanguineus s.l. Significant LC50 and LC90 values of GOT were evaluated (13.4 and 21.5 mg/mL, respectively) for the adulticidal activity, (2.81 and 4.46 mg/mL, respectively) for ovicidal activity and (2.44 and 4.45 mg/mL, respectively) for larvicidal activity. The safety of formula A has been proven by the absence of its cytotoxicity on a cell line of human epidermoid carcinoma. Citronella and carvacrol were the major compounds identified in the commercial essential oils of P. graveolens and O. majorana, respectively. Formula A was used in a field control trial for almost 8 months, during the tick infestation season (April to November, 2022). Fourteen naturally infested dogs were divided into two groups, each with seven dogs. One group received formula A spraying five times during an experiment that continued for 8 months, while the other group received treatment with commercially available malathion acaricide. The animals were sprayed on five occasions throughout the experiment (April, June, July, August, and September). The results showed a substantial percentage of effectiveness after the first application of formula A with a 99.3% reduction in tick count at day 28 post-application (PA). In the case of severe infestation 60 days after the first application of formula A (more than 180 ticks per dog), the second application was done, achieving an efficacy of 54.9% at day 3 PA, so an emergency spray was done at day 5 PA to combat the rest of the tick infestation, achieving efficacy of 99% after 3 days. Consequently, a regular spray (third, fourth, and fifth application) was done every 35 days. This regular spray revealed 100% effectiveness at 14 days PA. Biochemical parameters of treated dogs were evaluated to confirm the safety of formula A. Creatinine, ALT, and albumin of the dogs treated with formula A were within the normal range of dogs, while urea and AST were higher than the normal range. In conclusion, formula A can safely treat R. sanguineus s.l. infestations in dogs with regular application every 5 weeks.

The effect of Aromatherapy with Pelargonium graveolens (P. graveolens) on the fatigue and sleep quality of critical care nurses during the Covid-19 pandemic: A randomized controlled trial.

OBJECTIVES: Measures to reduce nurses' fatigue are necessary to improve the patient's care and the nurse's health and well-being. This study investigated the effectiveness of aromatherapy with Pelargonium graveolens (P. graveolens) essential oil on fatigue and sleep quality of nurses working in intensive care units (ICU). METHODS: In this double-blind, randomized, controlled clinical trial, 84 nurses working in the ICU of Covid-19 patients were assigned to two groups of P. graveolens and placebo by the stratified block method. The intervention group inhaled one drop of pure P. graveolens. The placebo group inhaled one drop of pure sunflower oil in three consecutive shifts (morning or evening) and each shift twice for 20 min. Using the Visual Analog Fatigue Scale (VAS-F), fatigue was measured 30 min before the intervention, immediately, and 60 min later. Also, on the morning of the intervention days, sleep quality was assessed with the Verran and Snyder-Halpern (VSH) Sleep Scale. Data analysis was performed using SPSS, version 24. Independent t-tests, Mann-Whitney, Chi-square tests, and MANOVA, were used. RESULTS: The mean score of fatigue immediately and 60 min after aromatherapy in the P. graveolens group was lower than in the control group (P Ë‚ 0.05). There was no significant difference between the mean sleep scores of nurses in the P. graveolens group before and after the intervention (P > 0.05). CONCLUSION: Inhalation aromatherapy with P. graveolens essential oil can reduce nurses' fatigue in the ICU. The findings of this study can make nurses interested in using aromatherapy as a self-care method.

Therapeutic Effects of Geranium Oil in MPTP-Induced Parkinsonian Mouse Model.

Parkinson's disease (PD) is an incurable neurodegenerative disease characterized by motor and non-motor disabilities resulting from neuronal cell death in the substantia nigra and striatum. Microglial activation and oxidative stress are two of the primary mechanisms driving that neuronal death. Here, we evaluated the effects of geranium oil on 1-methyl-4-phenyl-1,2,3,6-tetra-hydropyridine (MPTP) mouse model for PD, on microglial activation, and oxidative stress. We demonstrate that oral treatment with geranium oil improved motor performance in this model. The therapeutic effects of geranium oil were observed as a significant increase in rotarod latency and distance among the mice treated with geranium oil, as compared to vehicle-treated MPTP mice. Geranium oil also prevented dopaminergic neuron death in the substantia nigra of the treated mice. These therapeutic effects can be partially attributed to the antioxidant and anti-inflammatory properties of geranium oil, which were observed as attenuated accumulation of reactive oxygen species and inhibition of the secretion of proinflammatory cytokines from geranium oil-treated activated microglial cells. A repeated-dose oral toxicity study showed that geranium oil is not toxic to mice. In light of that finding and since geranium oil is defined by the FDA as generally recognized as safe (GRAS), we do not foresee any toxicity problems in the future and suggest that geranium oil may be a safe and effective oral treatment for PD. Since the MPTP model is only one of the preclinical models for PD, further studies are needed to confirm that geranium oil can be used to prevent or treat PD.

Safety and efficacy of a feed additive consisting of an essential oil from the herbaceous parts of Pelargonium graveolens L'Hér. (geranium rose oil) for all animal species (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil obtained from the herbaceous parts of Pelargonium graveolens L'Hér. (geranium rose oil), when used as a sensory additive in feed and water for drinking for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the use of geranium rose oil is safe up to the maximum proposed use levels of 5 mg/kg complete feed for all animal species. The FEEDAP Panel considered that the use in water for drinking is safe provided that the total daily intake of the additive does not exceed the daily amount that is considered safe when consumed via feed. No concerns for consumers were identified following the use of geranium rose oil up to the maximum proposed use level in feed. The additive under assessment should be considered as irritant to skin and eyes, and as a skin and respiratory sensitiser. The use of geranium rose oil at the proposed use level in feed was not expected to pose a risk to the environment. Since P. graveolens and its preparations were recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Odor Perception and Descriptions of Rose-Scented Geranium Pelargonium graveolens 'Dr. Westerlund'-Sensory and Chemical Analyses.

A recent study found that the natural scent from the rose-scented geranium Pelargonium graveolens 'Dr. Westerlund' had positive effects on stress reduction. Essential oils from many pelargonium species are known to have phytochemical properties and pharmacological activities. No study has, so far, explored and identified the chemical compounds and the sensory perception of these compounds in 'Dr. Westerlund' plants. Such knowledge would be an important contribution to an increased understanding of the effects of plants' chemical odor properties on human well-being, and link this to the expressed perceived scents. This study aimed to identify the sensory profile and suggest responsible chemical compounds of Pelargonium graveolens 'Dr. Westerlund'. The sensory and chemical analysis results revealed sensory profiles of Pelargonium graveolens 'Dr. Westerlund's and provided suggestions for the chemical compounds attributed to the sensory profiles. Further studies are recommended to investigate the correlation between volatile compounds and possible stress reduction in humans.

Wound Healing Properties of Pelargonium Graveolens L'Hér Extract Lipogel: In-Vivo Evaluation in an Animal Burn Model.

BACKGROUND: Pelargonium graveolens L'Hér has traditionally been used to reduce skin inflammation, and recent studies have confirmed antioxidant compounds in the plant's extract. The present study aimed to prepare a lipogel formulation from P. graveolens hydroalcoholic extract and evaluate its efficacy on the wound healing process in an animal model. MATERIAL AND METHODS: The aerial part extract of P. graveolens was prepared through percolation. Additionally, plastibase was prepared by mixing 5% of low-molecular-weight polyethylene with hot mineral oil (130°C). The extract (5%) was levigated in the mineral oil (5-15%) and dispersed in the cooled plastibase. The physical properties of the lipogel, thermal stability, and microbial limits were tested. Further, the effect of the lipogel in the wound healing rate was examined among male Wistar rats, and skin tissue samples were assessed histologically. RESULTS AND DISCUSSION: The results represented the best rheological and thermal stability characteristics in the formulation with 5% mineral oil (as the levigator). The lipogel-treated group had the least burn area compared to the silver sulfadiazine and negative control groups (p<0.05). The microscopic examination of tissue samples revealed increased collagen fiber production and maturation and significantly also faster epithelial repair among lipogel-treated rats than in the other two groups(p<0.05). CONCLUSION: The results indicated the significant therapeutic effects of P. graveolens lipogelon burn healing. The suitable physicochemical properties and the low lipogel production cost facilitate further scale-up studies.

Assessment of soil enzymatic resilience in chlorpyrifos contaminated soils by biochar aided Pelargonium graveolens L. plantation.

Chlorpyrifos (CP), a broad-spectrum organophosphorus insecticide, is known for deleterious effects on soil enzymatic activities. Hence, the present study aims to examine the resilience effect of biochar (BC) aided Pelargonium graveolens L. plantation on enzymatic activities of chlorpyrifos contaminated soil. The two chlorpyrifos contaminated agriculture soils (with concentrations: S1: 46.1 and S2: 95.5 mg kg-1) were taken for the pot experiment. The plant biomass, plant growth parameters, soil microbial biomass, and enzymatic activities such as alkaline phosphatase, N-acetyl glucosaminidase, aryl sulphatase, cellulase, ß-glucosidase, dehydrogenase, phenoloxidase, and peroxidase enzymes were  examined. Ecoenzyme activities and their stoichiometry were used to enumerate the different indices including geometric mean, weighted mean, biochemical activity indices, integrated biological response, treated-soil quality index, and vector analysis in all treatments. The results of the study demonstrated that the biochar incorporation enhanced the tolerance of P. graveolens (from 42-45% to 55-67%) in chlorpyrifos contaminated soil and reduced the CP accumulation in plants. A reduction in the inhibitory effect of chlorpyrifos on soil enzymatic activities and plant growth by BC incorporation was observed along with an increase in the activities of ecoenzymes (16.7-18.6%) in soil. The investigation indicated more microbial investments in C and P than that in N acquisition under CP stress. The BC amendment catalyzed the activities of lignin and cellulose-degrading enzymes and enhanced nutrition acquisition. The CP contamination and BC amendment have no significant effect on the oil quality of P. graveolens. The study demonstrated that BC-aided P. graveolens plantation offers sustainable phytotechnology for CP contaminated soil with an economic return.

Chemical Profiling and Biological Activities of Pelargonium graveolens Essential Oils at Three Different Phenological Stages.

The aim of this work was the determination of Pelargonium graveolens (aerial parts) volatile compounds at three developmental stages and the evaluation of their antioxidant, antidiabetic, dermaprotective, anti-inflammatory, and antibacterial effects. The aerial parts of Pelargonium graveolens were collected at three stages, namely the vegetative, beginning, and full flowering. Pelargonium graveolens essential oils were extracted from the dried materials of these aerial parts by hydrodistillation. The volatiles were analyzed by Gas Chromatography-Mass Spectrometry GC-MS, and the antioxidant activity was assessed by DPPH, ABTS, H2O2, and FRAP assays. The in vitro antidiabetic effect was evaluated by the inhibition of α-amylase, α-glucosidase, and lipase enzymes, while the antibacterial activity was assessed against six bacterial strains using an agar well diffusion assay and a microdilution method. The main constituents were menthol, menthene, eremophilene, isoborneol, isogeraniol, α-pinene, linalyl acetate, and 3-carene, with quantitative differences at the three phenological stages. The essential oil at the full flowering stage showed the best antioxidant activity, with IC50 values of 83.26 ± 0.01, 116.42 ± 0.07, 132.25 ± 0.11, and 48.67 ± 0.04 µg/mL for DPPH, FRAP, ABTS, and H2O2 assays, respectively. This oil also exhibited significant effects against α-amylase (IC50 = 43.33 ± 0.01 µg/mL), α-glucosidase (IC50 = 19.04 ± 0.01 µg/mL), lipase (IC50 = 24.33 ± 0.05 µg/mL), 5-lipoxygenase (IC50 = 39.31 ± 0.01 µg/mL), and tyrosinase (IC50 = 124.49 ± 0.07 µg/mL). The essential oil extracted at the full flowering stage showed the best antibacterial effect against a panel of microorganisms with diameter inhibition zones ranging between 11.00 ± 0.17 mm and 17.30 ± 0.17 mm and MIC values from 0.25% to 2% v/v. Overall, the results presented here suggest that the full flowering stage is the best optimal harvest time of Pelargonium graveolens for food and pharmaceutical applications.

Chemical Markers and Pharmacological Characters of Pelargonium graveolens Essential Oil from Palestine.

Pelargonium graveolens leaves are widely used in traditional medicine for relieving some cardiovascular, dental, gastrointestinal, and respiratory disorders. They are also used as food and tea additives in Palestine and many other countries. Consequently, this investigation aimed to describe the chemical markers, cytotoxic, antioxidant, antimicrobial, metabolic, and cyclooxygenase (COX) enzymes inhibitory characteristics of P. graveolens essential oil (PGEO) from Palestine utilizing reference methods. There were 70 chemicals found in the GCMS analysis, and oxygenated terpenoids were the most abundant group of the total PGEO. Citronellol (24.44%), citronellyl formate (15.63%), γ-eudesmol (7.60%), and iso-menthone (7.66%) were the dominant chemical markers. The EO displayed strong antioxidant activity (IC50 = 3.88 ± 0.45 µg/mL) and weak lipase and α-amylase suppressant effects. Notably, the PGEO displayed high α-glucosidase inhibitory efficacy compared with Acarbose, with IC50 doses of 52.44 ± 0.29 and 37.15 ± 0.33 µg/mL, respectively. PGEO remarkably repressed the growth of methicillin-resistant Staphylococcus aureus (MRSA), even more than Ampicillin and Ciprofloxacin, and strongly inhibited Candida albicans compared with Fluconazole. The highest cytotoxic effect of the PGEO was noticed against MCF-7, followed by Hep3B and HeLa cancer cells, with IC50 doses of 32.71 ± 1.25, 40.71 ± 1.89, and 315.19 ± 20.5 µg/mL, respectively, compared with doxorubicin. Moreover, the screened EO demonstrated selective inhibitory activity against COX-1 (IC50 = 14.03 µg/mL). Additionally, PGEO showed a weak suppressant effect on COX-2 (IC50 = 275.97 µg/mL). The current research can be considered the most comprehensive investigation of the chemical and pharmacological characterization of the PGEO. The results obtained in this study demonstrate, without doubt, that this plant represents a rich source of bioactive substances that can be further investigated and authenticated for their medicinal potential.

Effect of Pelargonium graveolens on Glucose Metabolism in Streptozotocin-Induced Diabetic Rats.

AIMS: The study aimed to assess the antihyperglycemic activity of Pelargonium graveolens. BACKGROUND: Pelargonium graveolens (P. graveolens) (Geraniaceae) is a medicinal plant frequently used in traditional medicine in Morocco and Algeria as remedy against a multitude of illnesses. Interestingly, it is used in the Moroccan pharmacopeia for managing diabetes. OBJECTIVE: The current study was carried out in order to assess the antihyperglycemic activity of P. graveolens in normal and streptozotocin(STZ)-induced diabetic rats, as well as to evaluate the acute toxicity of the leaves aqueous extract of Pelargonium graveolens (PGLAE). METHODS: The therapeutic effect of PGLAE at a dose of 40 mg/kg on blood glucose levels was investigated in normal and STZ-induced diabetic rats after a single oral (6h) and a repeated (15 days) oral administration. The acute toxicity of the PGLAE was examined in accordance the OECD test guideline. Post-treatment, body weight, signs of toxicity, and/or mortality were observed for 14 days. Further assays such as the oral glucose tolerance test, histopathological examination and antioxidant activity was also performed according to standard protocols. RESULTS: Findings exhibited that both single and repeated oral doses of PGLAE (40 mg/kg) produced significant reduction of blood glucose levels in normal and diabetic rats. All treated animals survived and no apparent adverse effects were observed during the duration of the acute toxicity study. Importantly, oral LD50 of PGLAE was greater than 2000 mg/kg BW. Furthermore, a remarkable influence on glucose tolerance was also noticed after PGLAE treatment. Moreover, PGLAE was able to improve histopathological structure of liver and possesses a potential antioxidant effect in vitro. CONCLUSION: In conclusion, this study reports the antidiabetic effect of PGLAE in rats supporting then its traditional use for the management of diabetes.

Antimicrobial synergism and antibiofilm activities of Pelargonium graveolens, Rosemary officinalis, and Mentha piperita essential oils against extreme drug-resistant Acinetobacter baumannii clinical isolates.

Rosemary officinalis L., Pelargonium graveolens L., and Mentha piperita L., essential oils are used by complementary medicine specialists simultaneously with traditional antibiotics for treatment purposes. The chemical composition of essential oils was analyzed by the gas chromatography-mass spectrometry method. In vitro antibacterial and antibiofilm activities of the essential oils were tested against extreme drug-resistant (XDR) colistin-resistant and colistin susceptible Acinetobacter baumannii clinical strains. The synergistic activities between essential oils and colistin antibiotics were investigated by the checkerboard method. The highest antibacterial effect was detected in mint essential oil (2.5-5 µl/ml), followed by pelargonium essential oil (5-20 µl/ml) and rosemary essential oil (5-20 µl/ml). The combination of rosemary essential oil or pelargonium essential oil with colistin showed strong synergistic activity in most of the bacterial strains tested (fractional inhibitory concentration index ≤ 0.5; synergy). As a result of the combination of mint essential oil and colistin, an indifferent effect was observed in only two bacterial strains, and other strains could not be evaluated. No antagonistic effects were observed in any of the tested essential oils. As a result of the effectiveness of the combination, the minimum inhibitory concentration (MIC) values of colistin in XDR-A. baumannii clinical isolates decreased 2-32 fold. Additionally, the sub-MIC concentration of essential oils exhibited an inhibitory effect (48-90%) against the biofilm layer of tested A. baumannii strains.

Harnessing Endophytic Fungi for Enhancing Growth, Tolerance and Quality of Rose-Scented Geranium (Pelargonium graveolens (L'Hér) Thunb.) Plants under Cadmium Stress: A Biochemical Study.

Heavy metal contamination in soil is increasing rapidly due to increasing anthropogenic activities. Despite the importance of rose-scented geranium as a medicinal plant, little attention was paid to enhancing its productivity in heavy metal-polluted soil. In this regard, endophytes improve plant resistance to heavy metal toxicity and enhance its tissue quality. Here, the impact of the three endophytic fungi Talaromyces versatilis (E6651), Emericella nidulans (E6658), and Aspergillus niger (E6657) on geranium growth, tolerance, and tissue quality under cadmium (Cd) stress was investigated. In contrast to E. nidulans, T. versatilis and A. niger enhanced geranium growth and the stimulatory effect was more pronounced under Cd-stress. The three endophytes significantly alleviated Cd accumulation and increased mineral content in geranium leaves. In addition, endophytic fungi successfully alleviated Cd-induced membrane damage and reinforced the antioxidant defenses in geranium leaves. Inoculation with endophytes stimulated all the antioxidant enzymes under Cd-stress, and the response was more obvious in the case of T. versatilis and A. niger. To reduce the toxicity of tissue-Cd levels, T. versatilis and A. niger upregulated the detoxification mechanisms; glutathione-S-transferase, phytochelatin, and metallothionein levels. Moreover, endophytic fungi improved the medicinal value and quality of geranium by increasing total antioxidant capacity (TAC), phenolic compound biosynthesis (phenylalanine ammonia-lyase), and vitamin content as well as the quantity and quality of essential oil, particularly under Cd-stress conditions. The variation in the mechanisms modulated by the different endophytic fungi was supported by Principal Component Analysis (PCA). Overall, this study provided fundamental insights into endophytes' impact as a feasible strategy to mitigate the phytotoxicity hazards of Cd-stress in geranium and enhance its quality, based on the growth and biochemical investigations.

Potentiation of anti-Helicobacter pylori activity of clarithromycin by Pelargonium graveolens oil.

BACKGROUND AND STUDY AIM: Peptic ulcer is one of the most serious diseases in Egypt, affecting more than one-third of the population. Helicobacter pylori is the main organism responsible for peptic ulcer formation. These ulcers can lead to chronic active gastritis and lymphoma. As such, in this study, we evaluate the efficacy of Pelargonium graveolens oil for the treatment of H pylori, as well as its synergistic effects with the antibiotic clarithromycin (CLR). PATIENTS AND METHODS: We evaluated the chemical composition of P. graveolens volatile oil as well as its anti-Helicobacter activities. We assessed the volatile oil components using gas chromatography coupled with mass spectrometry. We determined anti-H. pylori potential using a micro-well dilution method. RESULTS: We identified 92 compounds from the oil. Citronellol, geraniol, citronellyl formate, and isolongifolan-7-α-ol were the predominant components (15.64%, 11.31%, 10.19%, and 7.84%, respectively). The oil exhibited a good activity against H. pylori at an minimal inhibitory concentration of 15.63 µg/ml. Once we combined the volatile oil with CLR, a significant synergistic effect appeared at an fractional inhibitory concentration index of 0.38 µg/ml. CONCLUSION: The in-vitro interaction between the P. graveolens oil and CLR improved the antimicrobial activity of the latter, suggesting that further studies are needed to determine formulations for potential antimicrobial applications in food and pharmaceuticals.

Synergistic Activity of New Diclofenac and Essential Oils Combinations against Different Candida spp.

According to recent studies, Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) have shown a good antimicrobial and antifungal activity. Their association with essential oils (EOs) could be useful for the treatment of infections caused by Candida spp. The aim of this studyis to evaluate the synergistic antifungal activity of new combinations between Diclofenac Sodium Salt (DSS), a widely used NSAID, with EOs of Mentha × piperita, Pelargonium graveolens and Melaleuca alternifolia. The in-vitro antifungal activity was determined on different Candida strains. The determination of the chemical composition of EOs was carried out by gaschromatography-massspectrometry (GC-MS). Susceptibility testing of planktonic cells was performed by using the broth microdilution assay and checkerboard methods. Minimum Inhibitory Concentrations (MIC) of DSS was in a range from 1.02 to 2.05 µg/mL reaching a MIC value of 0.05 µg/mL when combined with Pelargonium graveolens (FICI = 0.23-0.35) or Menthapiperita (FICI = 0.22-0.30) EOs. These preliminary results show thatthe combination of the EOs with DSS improves the antifungal activity on all the tested Candida strains.

Cytosolic geraniol and citronellol biosynthesis require a Nudix hydrolase in rose-scented geranium (Pelargonium graveolens).

Geraniol, citronellol and their esters are high-value acyclic monoterpenes used in food technology, perfumery and cosmetics. A major source of these compounds is the essential oil of rose-scented geraniums of the genus Pelargonium. We provide evidence that their biosynthesis mainly takes place in the cytosol of glandular trichomes via geranyl monophosphate (GP) through the action of a Nudix hydrolase. Protein preparations could convert geranyl diphosphate (GDP) to geraniol in in vitro assays, a process which could be blocked by inorganic phosphatase inhibitors, suggesting a two-step conversion of GDP to geraniol. Pelargonium graveolens chemotypes enriched in either geraniol or (-)-citronellol accumulate GP or citronellyl monophosphate (CP), respectively, the presumed precursors to their monoterpenoid end products. Geranyl monophosphate was highly enriched in isolated glandular trichomes of lines producing high amounts of geraniol. In contrast, (-)-isomenthone-rich lines are depleted in these prenyl monophosphates and monoterpene alcohols and instead feature high levels of GDP, the precursor to plastidic p-menthane biosynthesis. A Nudix hydrolase cDNA from Pelargonium glandular trichomes, dubbed PgNdx1, encoded a cytosolic protein capable of hydrolyzing GDP to GP with a KM of about 750 nm but is only weakly active towards farnesyl diphosphate. In citronellol-rich lines, GDP, GP and CP were detected in nearly equimolar amounts, while citronellyl diphosphate was absent, suggesting that citronellol biosynthesis may proceed by reduction of GP to CP in this species. These findings highlight the cytosol as a compartment that supports monoterpene biosynthesis and expands the roles of Nudix hydrolases in the biosynthesis of plant volatiles.

Chemical Profile and Use of the Peat as an Adsorbent for Extraction of Volatile Compounds from Leaves of Geranium (Pelargonium graveolens L' Herit).

Volatile organic compounds (VOCs) from leaves of geranium (Pelargonium graveolens L' Herit) were extracted by dynamic headspace using Porapak Q (HSD-P) as adsorbent and peat, a novel adsorbent in the extraction of plant volatiles, analyzed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography-flame ionization (GC/FID), and the results were compared with those obtained by hydrodistillation (HD). The yield volatiles changed with the extraction method. HD was more efficient for extracting linalool (11.19%) and citronellyl formate (9.41%). Citronellol (28.06%), geraniol (38.26%) and 6,9-guaiadiene (9.55%) and geranyl tiglate (8.21%) were the major components identified by dynamic headspace using peat (HSD-T), while citronellol (16.88%), geraniol (13.63%), 6,9-guaiadiene (16.98%) and citronellyl formate (6.95%) were identified by dynamic headspace using Porapak Q (HSD-P). Furthermore, this work showed, for the first time, that in natura peat is useful to extract VOCs from leaves of geranium.

The effects of UV-B radiation on genetic and biochemical changes of Pelargonium graveolens L'Her.

Ultraviolet radiation induces biochemical and genetic changes in plants. The aim of this study was to investigate the effects of UV-B radiation on genetic stability, phenolic compounds and antioxidant activity of Pelargonium graveolens L'Her. Plant cuttings were exposed to 0, 0.12. 0.26 and 0.38 W/m2 of UV-B radiation. Results indicated that by increasing the UV-B radiation intensity, total phenols, flavonoids and anthocyanin contents, Phenylalanine ammonia lyase activity and antioxidant capacity were increased. Analysis of four flavonols (quercetin, myricetin, kaempferol and rutin) contents of leaves extract by HPLC indicated that these four flavonols were enhanced in all treated plants and also the ratio of quercetin to kaempferol (Q/K) showed a significant increase (P ≤ 0.05) in UV-B treated plants in compare to control. To evaluate the genetic variation in treated plants, 10 ISSR primers were used. The highest level of percentage of polymorphism (P%), Shannon index (I), number of effective allele (Ne) and Nei' genetic diversity (He), were observed at the highest UV-B radiation (0.38 W/m2). The AMOVA analysis also showed a significant genetic differentiation (P ≥ 0.001) among the studied groups, and confirmed the differentiation of groups obtained by the cluster analysis of molecular data. Overall, these results showed that biochemical changes in different intensities of UV-B were in line with genetic variations, so that the highest biochemical and genetic variations were observed in 0.38 W/m2 treatment.

The Chemical Composition and Anti-mycobacterial Activities of Trachyspermum copticum and Pelargonium graveolens Essential Oils.

BACKGROUND: Microbial resistance to antibiotics and their adverse effects related to these antibiotics are a matter of global public health in the 21th century. The emergence of drug-resistant strains, has gained the interest of the scientists to discover new antimicrobial agents from the essential oil of medicinal plants. METHODS: Anti-mycobacterial effects of Trachyspermum copticum and Pelargonium graveolens essential oils were determined against multi-drug resistant clinical strains of Mycobacterium tuberculosis, Mycobacterium kansasii, Mycobacterium fortuitum and standard strain of Mycobacterium tuberculosis H37Rv by a Broth micro-dilution method. Pelargonium graveolens plant named Narmada was discovered by Kulkarni R.N et al. (Patent ID, USPP12425P2) and a formulation comprising thymol obtained from Trachyspermum is useful in the treatment of drug-resistant bacterial infections (Patent ID, US6824795B2). The chemical composition of hydro-distilled essential oils was determined by GC and GC-MS. RESULTS: Minimum Inhibitory Concentration (MIC) values for T. copticum essential oil against tested isolates were ranged from 19.5 µg/mL to 78 µg/mL. The least minimum inhibitory concentration of P. graveolens extract against M. Kansasii and MDR-TB was 78 µg/ml. CONCLUSION: The results of the present research introduced T. copticum and P. graveolens essential oils as a remarkable natural anti-mycobacterial agent, but more pharmacological studies are required to evaluate their efficacy in animal models.