Exposure to single-walled carbon nanotubes differentially affect in vitro germination, biochemical and antioxidant properties of Thymus daenensis celak. seedlings

Carbon nanomaterials such as single-walled carbon nanotubes (SWCNTs) offer a new possibility for phyto-nanotechnology and biotechnology to improve the quality and quantity of secondary metabolites in vitro. The current study aimed to determine the SWCNTs effects on Thyme (Thymus daenensis celak.) seed germination. The seedlings were further assessed in terms of morphological and phytochemical properties. Sterile seeds were cultured in vitro and treated with various concentrations of SWCNTs. Biochemical analyses were designed on seedling sample extracts for measuring antioxidant activities (AA), total flavonoids (TFC) and phenolic contents, and the main enzymes involved in oxidative reactions under experimental treatments. The results indicated that an increase in SWCNTs concentration can enhance the total percentage of seed germination. The improvement was observed in samples that received SWCNTs levels of up to 125 µg ml-1, even though seedling height and biomass accumulation decreased. Seedling growth parameters in the control samples were higher than those of grown in SWCNT-fortified media. This may have happened because of more oxidative damage as well as a rise in POD and PPO activities in tissues. Additionally, secondary metabolites and relevant enzyme activities showed that maximum amounts of TPC, TFC, AA and the highest PAL enzyme activity were detected in samples exposed to 62.5 µg ml-1 SWCNTs. Our findings reveal that SWCNTs in a concentration-dependent manner has different effects on T. daenensis morphological and phytochemical properties. Microscopic images analysis revealed that SWCNTs pierce cell walls, enter the plant cells and agglomerate in the cellular cytoplasm and cell walls. The findings provide insights into the regulatory mechanisms of SWCNTs on T. daenensis growth, germination and secondary metabolites production.

Chemical Composition and Antifungal and Antibiofilm Effects of Vitex pseudo-negundo Essential Oil against Pathogenic Fungal Strains

Background

Vitex pseudo-negundo is a plant of the Lamiaceae family that grows in different parts of the world and the vicinity of seasonal rivers in Iran.

Methods

The chemical composition of the Vitex pseudo-negundo essential oils was distilled and evaluated using gas chromatography/mass spectrometry. The antifungal activity of the essential oils against the fungal strains was analyzed by broth microdilution methods as suggested by the Clinical and Laboratory Standards Institute. Furthermore, the antibiofilm activity of the Vitex pseudo-negundo essential oils was assessed using the XTT reduction assay.

Results

Based on GC/MS analysis, the major components of the Vitex pseudo-negundo essential oils were α-pinene, α-terpinyl acetate, limonene, and (E)-caryophyllene. The growth of tested yeasts was inhibited at concentrations ranging from 2 to 64 μl/mL. Vitex pseudo-negundo fruit essential oil was the most effective in inhibiting yeast growth. Moreover, the essential oils exhibited antifungal activity against filamentous fungi strains. Additionally, the biofilm formation of Candida albicans was inhibited by the leaf, flower, and fruit of the essential oils.

Conclusion

Considering the significant antifungal activities of these essential oils, they can be considered a potential source for formulating novel agents to control fungal infections.

The use of silicon and mycorrhizal fungi to mitigate changes in licorice leaf micromorphology, chlorophyll fluorescence, and rutin content under water-deficit conditions

In this study, the effects of water-deficit conditions, silicon (Si) fertilizer (300 ppm), and arbuscular mycorrhizal (AM) inoculation by Claroiedoglomus etunicatum were evaluated on several features of licorice (Glycyrrhiza glabra L.). The measurable features were photosynthetic parameters, rutin content in aerial parts, and leaf micromorphology. Drought was administered at five levels determined by the percentage of field capacity (FC), i.e. 100, 80, 60, 40, and 20% of FC. Leaf extracts were utilized for measuring rutin content (via HPLC), and photosynthetic pigments; measurement of stomatal density, and trichome analysis were performed by scanning electron microscopy (SEM). Under severe drought stress, leaf area decreased by 50.84%, compared to well-irrigated plants. A significant decrease in leaf numbers (32.52%) was observed because of deficit irrigation. AM and Si improved chlorophyll fluorescence, which corresponded to the maximum efficiency of photosystem II. Rutin content decreased significantly under deficit irrigation. Also, the integration of AM and Si treatments positively affected rutin quantity under various irrigation regimes. Under moderate stress (60% FC), using AM and/or Si treatments reduced the stomatal length by 61.22 and 52.98%, respectively. Interestingly, a significant reduction in stomatal density towards control was observed as a result of the integrated treatments of Si and AM (58.28% at W₂₀ and 59.82% at W₁₀₀), which helped plants reduce water loss when facing drought stress. Principal component analysis (PCA) showed that photosynthetic pigments, chlorophyll fluorescence, and rutin changed quantitatively under moderate drought stress, while more variations were observed in leaf epidermal micromorphology under severe drought stress. These findings revealed that Si and AM, by exogenous application, synergistically mitigated the effects of drought stress on licorice.

Adaptation of Glycyrrhiza glabra L. to water deficiency based on carbohydrate and fatty acid quantity and quality

Water deficit affects agricultural systems negatively globally. This research objective was to mitigate drought's detrimental effects on plants metabolite profiling by utilizing biofertilizers and mineral nutrition. The carbohydrate content and fatty acid profile of Licorice (Glycyrrhiza glabra) were assessed under Silicon (Si) nutrition, Claroiedoglomus etunicatum inoculation (F), and drought stress (100, 80, 60, 40, and 20% of field capacity (FC)). Results showed that Si application increased total sugar content under severe drought levels (20 and 40% FC) and made it reach 12.41 and 12.63 g/100 g _DW, respectively. Sucrose, as the predominant sugar of licorice, was at its highest level (13.1 g/100 g _DW) in response to integrated values of F and Si (60% FC). Gas chromatography-mass spectrometry showed that the majority of fatty acid components in plants were 9-Octadecenoic acid (8.72-71.27%), 9,12-Octadecadienoic acid (0.1-56.43%), Hexadecanoic acid (12.84-30.59%), Octadecanoic acid (6.9-15.3%), Docosanoic acid (0.57-2.77%), Eicosanoic acid (1.07-2.64%), and 7-Hexadecenoic acid (0.26-2.62%). Since a lower omega6/omega3 ratio represents a healthier product, the lowest ratio (0.25%) was observed in well-watered inoculated plants. Also, severe drought-treated plants under integrated Si and F applications showed a low omega6/omega3 ratio (1.88%). In conclusion, Si and F improved synergistically the carbohydrate content and fatty acid profile in plants, despite the drought stress.

Evaluation of metabolites in Iranian Licorice accessions under salinity stress and Azotobacter sp. inoculation

Licorice (Glycyrrhiza glabra L.) is an industrial medicinal plant that is potentially threatened by extinction. In this study, the effects of salinity (0 and 200 mM sodium chloride (NaCl)) and Azotobacter inoculation were evaluated on 16 licorice accessions. The results showed that salinity significantly reduced the fresh and dry biomass (FW and DW, respectively) of roots, compared to plants of the control group (a decrease of 15.92% and 17.26%, respectively). As a result of bacterial inoculation, the total sugar content of roots increased by 21.56% when salinity was applied, but increased by 14.01% without salinity. Salinity stress increased the content of glycyrrhizic acid (GA), phenols, and flavonoids in licorice roots by 104.6%, 117.2%, and 56.3%, respectively. Integrated bacterial inoculation and salt stress significantly increased the GA content in the accessions. Bajgah and Sepidan accessions had the highest GA contents (96.26 and 83.17 mg/g DW, respectively), while Eghlid accession had the lowest (41.98 mg/g DW). With the bacterial application, the maximum amounts of glabridin were obtained in Kashmar and Kermanshah accessions (2.04 and 1.98 mg/g DW, respectively). Bajgah and Kashmar accessions had higher amounts of rutin in their aerial parts (6.11 and 9.48 mg/g DW, respectively) when their roots were uninoculated. In conclusion, these results can assist in selecting promising licorice accessions for cultivation in harsh environments.

Microbial amelioration of salinity stress in endangered accessions of Iranian licorice (Glycyrrhiza glabra L.)

BACKGROUND

Glycyrrhiza glabra L. is a medicinal and industrial plant that has gone extinct due to different abiotic stress caused by climate change. To understand how the plant-associated microorganism can support this plant under salinity, we collected sixteen Iranian accessions of G. glabra L., inoculated their rhizomes with Azotobacter sp. (two levels, bacterial treatments, and no-bacterial treatments, and grown them under salinity stress (NaCl levels; 0, and 200 mM).

RESULTS

Two accessions of Bardsir and Bajgah significantly showed higher resistant to salinity, for example by increasing crown diameter (11.05 and 11 cm, respectively) compared to an average diameter of 9.5 in other accessions. Azotobacter inoculation caused a significant increase in plant height and crown diameter. Among studied accessions, Kashmar (46.21%) and Ilam (44.95%) had the highest rate of membrane stability index (MSI). Evaluation of enzyme activity represented that bacterial application under salinity, increased polyphenol oxidase (PPO) (0.21 U mg^-1 protein), peroxidase (POD) (3.09 U mg^-1 protein U mg^-1 protein), and phenylalanine ammonia-lyase (PAL) (17.85 U mg^-1 protein) activity. Darab accession showed the highest increase (6.45%) in antioxidant potential compared with all studied accessions under Azotobacter inoculation. According to principal component analysis (PCA), it was found that the accession of Meshkinshahr showed a more remarkable ability to activate its enzymatic defense system under salt stress. Also, three accessions of Meshkinshahr, Eghlid, and Ilam were categorized in separated clusters than other accessions regarding various studied treatments.

CONCLUSION

Analysis indicated that five accessions of Meshkinshahr, Rabt, Piranshahr, Bardsir, and Kermanshah from the perspective of induced systematic resistance are the accessions that showed a greater morphophysiological and biochemical outcome under salinity. This study suggested that, inoculation of with Azotobacter on selected accession can relieve salt stress and support industrial mass production under abiotic condition.

Eco-friendly 'ochratoxin A' control in stored licorice roots - quality assurance perspective

According to toxicity data, ochratoxin A (OTA) is the second most important mycotoxin and is produced by Aspergillus and Penicillium. As a natural antifungal agent, clove essential oil (CEO) is a substance generally recognised as safe (GRAS) and shows strong activity against fungal pathogens. Here, we aimed to investigate the control efficacy of CEO in nano-emulsions (CEN) against OTA production in licorice roots and rhizomes during storage. The experiments were performed under simulated conditions of all four seasons (i.e. Spring, Summer, Autumn and Winter). Relative humidity (RH) and temperature were simulated in desiccators along with various salt solutions in incubators. Fresh licorice roots were immersed in CEN at various concentrations (150, 300, 600, 1200 and 2400 µl/l). Before utilising the nano-emulsions, we measured their polydispersity index and mean droplet size by the dynamic light scattering (DLS) technique. Also, the chemical composition of the CEO was determined using GC and GC-MS analyses. Sampling was carried out to monitor OTA once every five days. The samples were dried immediately and analysed by high-performance liquid chromatography (HPLC). Results showed that various concentrations of CEN inhibited the growth of fungi and OTA production. The most effective CEN concentrations were 1200 and 2400 µl/l, which reduced OTA production to 19 and 20 ppb under Winter and Autumn conditions, respectively. These results suggest an effective eco-friendly method for the storage of licorice to reduce postharvest fungal decay.

Therapeutic Efficacy of Great Plantain (Plantago major L.) in the Treatment of Second-Degree Burn Wounds: A Case-Control Study

BACKGROUND

Great plantain (Plantago major L. or P.major) is a medicinal plant that is available all around the world. The whole plant has several bioactive compounds including terpenoids, flavonoids, phenolic compounds, alkaloids, fatty acids, iridoid glycosides, polysaccharides, and vitamins. Scientific studies have recognized several medical benefits like wound healing, anti-inflammatory, antimicrobial, antiulcerative, and antioxidative agents. The wound-healing capacity of this plant has been investigated under in vivo and ex vivo conditions. In the current study, we aim to compare the therapeutic effect of the P.major extract with 1% sulfadiazine on the healing of second-degree burn wounds.

METHOD

Second-degree burn victims were included in our study. The investigation and control group, respectively, received P. major ointment 10% and silver sulfadiazine ointment 1%. The bacterial culture from the wound site was taken on days 3, 7, 10, 13, and last day of hospitalization. Patients' subjective complaints were obtained through the visual analog scale (VAS). All patients were treated and evaluated in the hospital.

RESULT

Among the 15 patients, 11 were male, and the mean age was 33.3 years. The average complete healing duration was 11.73 vs. 13 days in the P. major and control group, respectively (P=0.166). On the third day, infection control was similar between the two groups, and on the seventh day, all bacterial cultures were negative. Although there was a significant reduction in pain scores during the recovery time, no significant differences in pain reduction were noted between the two groups (P=0.849).

CONCLUSION

We showed that P.major ointment is a safe and suitable herbal compound in the treatment of second-degree burn wounds that not only has wound-healing properties but also is an analgesic and antimicrobial compound.

Antimicrobial core-shell electrospun nanofibers containing Ajwain essential oil for accelerating infected wound healing

Treatment of skin injuries is still facing major challenges, such as chronicity and infections, particularly those caused by multi-drug resistance pathogens. An effective treatment of such wounds should accelerate the wound healing process while preventing bacterial contamination. Here, a novel core-shell nanofiber mat was fabricated comprising gelatin/polyvinyl alcohol (as a core) and aloe vera/arabinose/polyvinylpyrrolidone (as a shell) for accelerating the healing process of bacteria-infected wounds. Trachyspermum Ammi (Ajwain) essential oil (EO), as a potent and natural antimicrobial agent against microorganisms, was incorporated into the core of nanofiber mats using coaxial electrospinning. The microscopy images demonstrated the successful fabrication of the core-shell structure with a uniform fiber size of 564 ± 106.35 nm. Moreover, Ajwain EO-loaded nanofiber mat (core-shell/EO) provided excellent antimicrobial activity and antioxidant ability. The in vitro and ex vivo release of Ajwain EO from the fabricated nanofiber mat corroborated a prolonged release profile. Furthermore, in vivo antibacterial activity, wound closure, and histomorphological examinations showed the high efficacy of the core-shell/EO mat in the treatment of Staphylococcus aureus-infected full-thickness rat wounds compared to standard control treatment with a gauze. Overall, these results represent the core-shell/EO mat's potential as a newly developed wound dressing for bacteria-infected full-thickness skin injuries.

Core-shell chitosan/PVA-based nanofibrous scaffolds loaded with Satureja mutica or Oliveria decumbens essential oils as enhanced antimicrobial wound dressing

Wounds are prone to bacterial infections, which cause a delayed healing process. Regarding the emergence of bacterial resistance to common antibiotics, using natural antimicrobial agents can be beneficial. Chitosan is a biological polymer, which has shown partial antioxidant and antimicrobial activities. In this study, core-shell nanofibrous scaffolds composed of chitosan (CS)/polyvinyl alcohol (PVA) as the core and polyvinylpyrrolidone (PVP)/ maltodextrin (MD) as the shell were developed. Satureja mutica (S. mutica) or Oliveria decumbens (O. decumbens) essential oil (EO) was encapsulated into the core of the produced scaffolds. The broth microdilution analysis showed significant antimicrobial activity of the EOs. The SEM analysis indicated that the unloaded and loaded core-shell scaffolds with S. mutica or O. decumbens EO had a uniform, beadless structure with fiber mean diameters of 210 ± 50, 250 ± 45, and 225 ± 46 nm, respectively. The CS/PVA-PVP/MD and CS/PVA/EO-PVP/MD scaffolds indicated suitable mechanical properties. The addition of the studied EOs enhanced the antioxidant activity of the scaffolds. The antimicrobial test of produced scaffolds showed that loading of 10% S. mutica or O. decumbens EO could broaden the microbicidal activity of the CS/PVA-PVP/MD scaffolds. These results revealed that the CS/PVA/EO-PVP/MD nanofibrous scaffolds are promising candidates for wound dressing.

Development of pre-emergence herbicide based on Arabic gum-gelatin, apple pectin and savory essential oil nano-particles: A potential green alternative to metribuzin

This study was conducted as a plot experiment to investigate the phytotoxicity effects of nano-encapsulated savory essential oil (EO) when it is incorporated separately into carbohydrate and protein natural polymers (Arabic gum-gelatin, apple pectin and gelatin) and two cross-linkers including one poly acid and one enzyme (citric acid and transglutaminase enzyme). Each product was tested as a pre-emergence herbicide against amaranth and tomato. The evaluations also involved determining the stability, morphology, encapsulation efficiency and release properties of the prepared formulations. Coating the savory EO with cross-linked biopolymers enhanced its stability and herbicidal activity, compared to the EO nano-emulsion without any polymer or cross-linker. Among the tested formulations, the strongest inhibitory effect against amaranth germination and growth was caused by Arabic gum-gelatin and apple pectin biopolymers at the concentration of 3 ml/L of EO, when cross-linked with citric acid. These two treatments had slight effects on tomato seedlings, however. The suppressive ability of the formulations was almost similar and comparable to the chemical herbicide metribuzin (1.75 g/L). In conclusion, Arabic gum-gelatin and apple pectin cross-linked by citric acid containing savory EO can be considered as potential, green and safe replacements for metribuzin in organic tomato production.

A natural post-emergence herbicide based on essential oil encapsulation by cross-linked biopolymers: characterization and herbicidal activity

This work describes efforts to encapsulate savory (Satureja hortensis L.) essential oil (EO) with different natural polymers (i.e., Arabic gum/gelatin (AGG), apple pectin (AP), gelatin (G)) and, as a separate set of experiments, with bio cross-linkers (i.e., citric acid and transglutaminase enzyme). The phytotoxic activity of encapsulated savory EO on tomato (Lycopersicon esculentum Mill.) and amaranth weed (Amaranthus retroflexus L.) was investigated. The micro-capsules were evaluated in terms of size, polydispersity, stability, encapsulation efficiency, morphology, and release properties. The Korsmeyer-Peppas model operated when EO was being released from the micro-capsules. Carvacrol (52.5%) and γ-terpinene (30.2%) comprised the main constituents of the savory EO. Based on the results, encapsulating the EO with cross-linked biopolymers increased the stability and herbicidal activity of EO, as compared to simple EO emulsions. Maximum toxicity injuries (MTI) were caused by encapsulations of apple pectin, cross-linked with APe enzyme (15 ml/L) on both plant species. MTI were observed 2 days after using the micro-encapsulated herbicides (MCHs). However, the injury caused by MCHs on tomato was not significant. The lowest values of fresh weight (2.80 g), chlorophyll a (0.194 mg/g Fw), and total chlorophyll content (0.219 mg/g Fw) of amaranth occurred in response to APe (15 ml/L). Moreover, using AP(e) (10 ml/L) caused the lowest values of starch (0.444 mg/g Fw) and flavonoid contents (4.18 mg Cat/g Fw) in amaranth which measured as 59% and 90% reductions, respectively, in comparison with the control. The highest values of MDA (0.0109 nmol/g Fw) and H₂O₂ (0.0432 μmol/g Fw) were observed in amaranth plants treated with AP(e) (10 ml/L). In summary, cross-linked apple pectin can perform well in slow release delivery systems of agrochemicals. It can be recommended for use in the production of commercial, EO-based natural herbicides.

Multi-walled carbon nanotubes stimulate growth, redox reactions and biosynthesis of antioxidant metabolites in Thymus daenensis celak. in vitro

This research was aimed at determining the effects of multi-walled carbon nanotubes (MWCNTs) on seed germination, seedling growth parameters and secondary metabolite (SM) production of Thymus daenensis in vitro. Seeds were aseptically cultured in Murashige and Skoog medium (MS) with various concentrations of MWCNTs (0, 125, 250, 500, 1000 and 2000 μg ml^-1). Seed germination and morphological changes in seedlings were measured. The measurements were aimed at quantifying the total phenolic contents (TPC) and flavonoids (TFC), antioxidant activities and the activity of polyphenol oxidase (PPO), l-phenylalanine ammonia-lyase (PAL), dehydrogenase (DHA) and peroxidase enzyme (POD) of the seedling extract. Seedling biomass and seedling height grew significantly as the MWCNTs level increased. The biomass and height peaked at 250 μg ml^-1 (0.41 ± 0.01 gr FW, 5.99 ± 0.55 cm) and then rapidly decreased to 0.040 ± 0.1 gr FW and 1.42 ± 0.24 cm in response to 1000 μg ml^-1, 30 days after the treatment. Additionally, SM and the analyses of enzyme activity revealed that the highest amounts of TPC (6.70 ± 0.06 mg GAE g^-1 DW), TFC (8.19 ± 0.01 mg QUE g^-1 DW), antioxidant activities (73.88 ± 0.47%) and maximum PAL activity (1.25 ± 0.08 mM cm g^-1 FW) were detected in plants grown on MS media fortified with 250 μg ml^-1 MWCNTs. The results reveal that MWCNTs in low doses (250 μg ml^-1) can encourage the production of biomass, elicit more SM from seedlings and enhance the biosynthesis of antioxidants. TEM images showed that MWCNTs could cross the plant cell wall and enter the cellular cytoplasm.

Chemical compositions and antifungal activities of Satureja macrosiphon against Candida and Aspergillus species

Background and Purpose:

Despite the various applications of Satureja species, there are limited data in this domain. Regarding this, the present study was conducted to investigate the essential oil (EO) biological activity of S. macrosiphon species in Iran.

Materials and Methods:

The EO of S. macrosiphon flowers was obtained by hydrodistillation. Chemical compositions of the EO were analyzed using gas chromatography-mass spectrometry. In addition, minimum inhibitory concentrations (MIC) were measured by means of the broth microdilution method. The estimation of antibiofilm and cytotoxic activities was also accomplished using the tetrazolium salt and MTT assays, respectively.

Results:

A total of 26 components were identified in the EO with linalool as the main constituent (28.46%). A MIC range value of 0.25-8 μL/mL was obtained against all of the tested fungi. The EO inhibited the biofilm development of the Candida tested strains at a concentration of 4-8 μL/mL. Cytotoxicity (IC₅₀) of EO against the HeLa cell was greater than the MIC concentration (6.49 μL/mL).

Conclusion:

Based on the findings, it was concluded that the EO of S. macrosiphon has the potential for further use as an antifungal agent.

Natural herbicide activity of Satureja hortensis L. essential oil nanoemulsion on the seed germination and morphophysiological features of two important weed species

The aim of the present study was to obtain an oil/water (O/W) nanoemulsion (NE) containing garden savory (Satureja hortensis) essential oil (EO) and evaluating its herbicidal activity against Amaranthus retroflexus and Chenopodium album. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were employed to determine the chemical composition of the EO. Carvacrol (55.6%) and γ-terpinene (31.9%) were the major EO components. Low energy method was applied, allowing achievement of EO nanodroplets. The NE also presented low polydispersity, and the mean droplet was below 130nm even after storage for 30d. Laboratory tests showed that the NE at different concentrations (100, 200, 400, 800, and 1000μL.L^-1) significantly (P≤0.05) reduced the germination indices and the seedling's growth in dose-response. The inhibitory effect was the greatest at 800μL.L^-1 NE. Overall, root length was more inhibited as compared to shoot length. Post-emergence application of NE at different concentrations (1000, 2000, 3000, 4000 and 5000μL.L^-1 of EO) on 2-4 true leaves' stage of the weeds caused significant (P≤0.05) decrease in the growth factors in dose-dependent manner. Complete lethality was observed by 4000μL.L^-1 NE sprayed on the weeds. Spraying of NE significantly (P≤0.05) reduced chlorophyll content in the tested weeds. Increasing in relative electrolyte leakage (REL) 1 and 5d after treatment represented significant cell membrane disruption and increased cell membrane permeability. Transmission electron microscope (TEM) pictures confirmed NE droplet size and demonstrated membrane destruction. The study approved that the NE of S. hortensis EO has herbicidal properties as it has high phytotoxic effect, and interferes with the germination, growth and physiological processes of the weeds. The production of NE from S. hortensis EO is a low energy method that offers a promising practical natural herbicide for weed control in organic agricultural systems.

In vitro ovicidal activity of Peganum harmala seeds extract on the eggs of Fasciola hepatica

Peganum harmala seeds extract has been previously reported to have antimicrobial and other medicinal properties. The aim of this study was to evaluate the ovicidal activity of the methanolic extract of P. harmala seeds against the eggs of F. hepatica. The phenolic compounds of the methanolic extract of P. harmala seeds were identified by HPLC analysis. Catechin, rutin, p-Coumaric acid, chloregenic acid and hesperetin were found to be the major phenolic compounds. F. hepatica eggs were collected from the gall bladder of naturally infected sheep. The eggs were exposed to two concentrations of P. harmala seeds extract (1 and 3 mg/mL) for 24 and 48 h. To investigate the effect of the P. harmala seeds extract on the miracidial formation, the treated eggs were incubated at 28 °C for 14 days. The results indicated that F. hepatica eggs were susceptible to the methanolic extract of P. harmala seeds. Following 24 h exposure of the eggs to P. harmala seeds extract with concentrations of 1 and 3 mg/mL, the miracidial formation reduced to 5 and 2.2 % respectively (compared with 60 % for the control group). Following 48 h of exposure of the eggs to P. harmala seeds extract with 1 mg/mL concentration, the miracidial formation reduced to 0.5 %. In this exposure time, no miracidial formation was observed in the eggs exposed to P. harmala seeds extract with concentration of 3 mg/mL. Therefore, the results of this study indicated that P. harmala seeds extract has high ovicidal activity against the eggs of F. hepatica. Accordingly, this extract may have the potential flukicidal activity against the immature and mature F. hepatica.

Antimicrobial activity of seven essential oils from Iranian aromatic plants against common causes of oral infections

Background:

Over the past two decades, there has been a growing trend in using oral hygienic products originating from natural resources such as essential oils (EOs) and plant extracts. Seven aromatic plants used in this study are among popular traditional Iranian medicinal plants with potential application in modern medicine as anti-oral infectious diseases.

Objectives:

This study was conducted to determine the chemical composition and antimicrobial activities of essential oils from seven medicinal plants against pathogens causing oral infections.

Materials and Methods:

The chemical compositions of EOs distilled from seven plants were analyzed by gas chromatography/mass spectrometry (GC/MS). These plants included Satureja khuzestanica, S. bachtiarica, Ocimum sanctum, Artemisia sieberi, Zataria multiflora, Carum copticum and Oliveria decumbens. The antimicrobial activity of the essential oils was evaluated by broth micro-dilution in 96 well plates as recommended by the Clinical and Laboratory Standards Institute (CLSI) methods.

Results:

The tested EOs inhibited the growth of examined oral pathogens at concentrations of 0.015-16 µL/mL. Among the examined oral pathogens, Enterococcus faecalis had the highest Minimum Inhibitory Concentrations (MICs) and Minimum Microbicidal Concentrations (MMCs). Of the examined EOs, S. khuzestanica, Z. multiflora and S. bachtiarica, showed the highest antimicrobial activities, respectively, while Artemisia sieberi exhibited the lowest antimicrobial activity.

Conclusions:

The excellent antimicrobial activities of the tested EOs might be due to their major phenolic or alcoholic monoterpenes with known antimicrobial activities. Hence, these EOs can be possibly used as an antimicrobial agent in treatment and control of oral pathogens.

Chemical Compositions and Antimicrobial Activities of Ocimum sanctum L. Essential Oils at Different Harvest Stages

BACKGROUND

Essential Oils (EOs) possess antibacterial properties and represent a natural source to treat infections and prevent food spoilage. Their chemical composition might be affected by the environmental condition and the developmental growth stages of the plant.

OBJECTIVES

The current study aimed to determine the variations in chemical compositions and antimicrobial activities of the EOs of Ocimum sanctum L. at different stages of harvesting.

MATERIALS AND METHODS

The oils constituents were analyzed by gas chromatography/mass spectrometry (GC/MS). The effects of three different harvest stages of O. sanctum EOs against most common causes of food-borne were evaluated by broth micro-dilution method as recommended by the Clinical and Laboratory Standards Institute (CLSI).

RESULTS

The analysis of the EOs indicated that eugenol was the major compound of the EOs at all developmental stages which reached its maximum level at the second stage. The results showed that the tested EOs exhibited antimicrobial activities against all of the examined pathogens at concentrations of 0.125-32 µL/mL, except Pseudomonas aeruginosa which was only inhibited by high concentrations of the floral budding and full flowering EOs. EO distilled from the second developmental growth stage (floral budding) of O. sanctum exhibited the strongest antibacterial activities against the food borne bacteria.

CONCLUSIONS

Considering the wide range of antimicrobial activities of the examined EOs, they might have the potential to be used to manage infectious diseases or extend the shelf life of food products.

Preventive and therapeutic effects of Zataria multiflora methanolic extract on hydatid cyst: an in vivo study

The phenolic compounds of Zataria multiflora extract, were identified by HPLC analysis. Gallic acid, catechin, caffeic acid, and quercetin were found to be the major phenolic compounds. Eighty healthy laboratory Balb/C mice were infected intraperitoneally by injection of 1500 viable protoscoleces and were divided into prevention (40 mice) and therapeutic (40 mice) groups. To prove the preventive effect of Z. multiflora extract on development of hydatid cyst, the 40 infected animals were allocated into three treatment groups including Z. multiflora (4 g/l in drinking water for 8 months), albendazole (150 mg/kg BW/day for 10 days) and untreated (control) group. To estimate the therapeutic effect of Z. multiflora extract on the hydatid cyst, after 8 months of infection, the infected mice were allocated into three experimental treatment groups including Z. multiflora (8 g/l in drinking water for 30 days), albendazole (300 mg/kg BW/day for 20 days) and untreated (control) group. At the end of the treatment period, all mice were euthanized and necropsied, the hydatid cysts were carefully removed, weighed and their size were recorded. Weight and size of the hydatid cysts significantly decreased (p<0.05) upon the treatment with Z. multiflora extract in both prevention and therapeutic groups. The germinal layer of the hydatid cysts recovered from the treated mice, either from the prevention or therapeutic group, were completely damaged at ultrastructural level by scanning electron microscopy.

Chemical Composition, Antifungal and Antibiofilm Activities of the Essential Oil of Mentha piperita L

Variations in quantity and quality of essential oil (EO) from the aerial parts of cultivated Mentha piperita were determined. The EO of air-dried sample was obtained by a hydrodistillation method and analyzed by a gas chromatography/mass spectrometry (GC/MS). The antifungal activity of the EO was investigated by broth microdilution methods as recommended by Clinical and Laboratory Standards Institute. A biofilm formation inhibition was measured by using an XTT reduction assay. Menthol (53.28%) was the major compound of the EO followed by Menthyl acetate (15.1%) and Menthofuran (11.18%). The EO exhibited strong antifungal activities against the examined fungi at concentrations ranging from 0.12 to 8.0 μL/mL. In addition, the EO inhibited the biofilm formation of Candida albicans and C. dubliniensis at concentrations up to 2 μL/mL. Considering the wide range of the antifungal activities of the examined EO, it might be potentially used in the management of fungal infections or in the extension of the shelf life of food products.

In vitro scolicidal effect of Satureja khuzistanica (Jamzad) essential oil

OBJECTIVE

To investigate the scolicidal effect of the Satureja khuzistanica (S. khuzistanica)essential oil from aerial parts of this herbal plant.

METHODS

The essential oil was obtained by hydrodistillation method. Gas chromatography (GC) and gas chromatography mass spectrometry (GC-MS) were employed to determine the chemical composition of the essential oil. Protoscolices were collected aseptically from sheep livers containing hydatid cyst. Protoscolices were exposed to various concentrations of the oil (3, 5 and 10 mg/mL) for 10, 20, 30, and 60 min. Viability of protoscolices was confirmed by 0.1% eosin staining.

RESULTS

: A total of 19 compounds representing 97.6% of the total oil, were identified. Carvacrol (94.9%) was found to be the major essential oil constituent. Scolicidal activity of S. khuzistanica essential oil at concentration of 3 mg/mL was 28.58, 32.71, 37.20 and 42.02%, respectively. This essential oil at concentration of 5 mg/mL killed 51.33, 66.68, 81.12, and 100% of protoscolices after 10, 20, 30 and 60 min, respectively. One hundred scolicidal effect was observed with S. khuzistanica essential oil at the concentration of 10 mg/mL after 10 min (comparing with 7.19% for control group).

CONCLUSIONS

The essential oil of S. khuzistanica is rich in carvacrol and may be used as a natural scolicidal agent.

Chemical Composition and Antimicrobial Activities of Essential Oils from Nepeta cataria L. against Common Causes of Food-Borne Infections

Nepeta cataria L. is traditionally consumed as a food additive. The effects of three different harvest stages of N. cataria essential oils (EOs) against most common causes of food-borne infections were evaluated by broth microdilution method as recommended by the Clinical and Laboratory Standards Institute (CLSI). The chemical composition of the EOs from N. cataria has been analyzed by gas chromatography/mass spectrometry (GC/MS). The analysis of the EOs indicated that 4a-α,7-α,7a-β-nepetalactone (55–58%) and 4a-α,7-β,7a-α-nepetalactone (30–31.2%) were the major compounds of the EOs at all developmental stages. The results showed that the tested EOs exhibited antimicrobial activities against the food-borne pathogens at concentrations of 0.125–2 μL/mL. Based on these results, the EO of N. cataria can possibly be used in food products as a natural preservative agent.

In vitro lethal effect of ajowan (Trachyspermum ammi L.) essential oil on hydatid cyst protoscoleces

Various chemical scolicidal agents have been used for inactivation of hydatid cyst protoscolices, but most of them are associated with adverse side effects. Since ajowan (Trachyspermum ammi) has been shown to have a number of medicinal properties, in this study the scolicidal effect of the essential oil (EO) from the fruits of this herbal plant was investigated. Ajowan EO was obtained by hydrodistillation method. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were employed to determine the chemical composition of the EO. Protoscoleces were exposed to various concentrations of EO (3, 5 and 10mg/mL) for 10, 20, 30, and 60 min. Viability of protoscolices was confirmed by 0.1% eosin staining. A total of 18 compounds representing 99.54% of the total oil, were identified. Thymol (50.07%), γ-terpinene (23.92%), and p-cymene (22.9%) were found to be the major EO constituents. While the mortality rate of protoscolices in the control group was 6.67%, scolicidal power of ajowan EO at concentration of 3mg/mL was 31.34, 35.98, 45.17, and 51.58% after 10, 20, 30, and 60 min, respectively. The EO at concentration of 5mg/mL killed 51.89, 72.20, 88.64, and 100% of protoscolices after 10, 20, 30, and 60 min, respectively. One hundred percent scolicidal activity was observed with ajowan EO at concentration of 10mg/mL after 10 min of exposure. The results of this study revealed that the EO of ajowan is rich in thymol, γ-terpinene and p-cymene, has high scolicidal power and it may be used as a natural scolicidal agent.

Antioxidant, nitric oxide scavenging and malondialdehyde scavenging activities of essential oils from different chemotypes of Zataria multiflora

The antioxidant, nitric oxide (NO) scavenging and malondialdehyde (MDA) scavenging activities of different Zataria multiflora (ZM) chemotype essential oils (EOs) were investigated. The main components are: ZM1 (carvacrol, p-cymene), ZM2 (carvacrol, p-cymene), ZM3 (carvacrol, p-cymene), ZM4 (linalool), ZM5 (carvacrol, p-cymene, thymol), ZM6 (thymol, carvacrol, p-cymene, γ-terpienene), ZM7 (thymol, p-cymene, γ-terpienene) and ZM8 (carvacrol, linalool, p-cymene, thymol). The antioxidant capacities were estimated to be 863 ± 55, 619 ± 27, 876 ± 32, 38 ± 9, 649 ± 50, 595 ± 40, 696 ± 41 and 618 ± 9 µg ascorbic acid equivalents per millilitre for ZM1 to ZM8, respectively. The NO scavenging values were estimated to be 54 ± 1.2, 50 ± 1.4, 63 ± 1, 0.60 ± 0.1, 53 ± 0.7, 53 ± 1.5, 38 ± 1.1 and 46.5 ± 3 µg ascorbic acid equivalents per millilitre for ZM1 to ZM8, respectively. The MDA scavenging values were estimated to be 19 ± 1, 9 ± 1, 24 ± 1, 1.6 ± 0.6, 12 ± 1, 11.7 ± 1, 10 ± 1 and 12.5 ± 1.3 µg ascorbic acid equivalents per millilitre for ZM1 to ZM8, respectively. Among these EOs, ZM3 with carvacrol and p-cymene had higher antioxidant, NO scavenging and MDA scavenging properties.

Stabilization of sunflower oil with Carum copticum Benth & Hook essential oil

In this study, application of various concentrations (0.025%, 0.05% and 0.075%) of Carum copticum essential oil (EO) were examined on oxidative stability of sunflower oil and there were compared to Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) during storage at 37 and 47 °C. The main compounds of EO were identified as thymol (50.07%), γ- terpinene (23.92%) and p-cymene (22.9%). Peroxide value (PV), anisidine value (AnV) and thiobarbituric acid (TBA) value measurement in sunflower oil showed that all concentrations of EO had antioxidant effect in comparison to BHA and BHT. Samples added with EO at 0.075% were the most stable during storage at both temperatures (P < 0.05). Furthermore, Totox value, antioxidant activity (AA), stabilization factor (F) and antioxidant power (AOP) determination confirmed efficacy of this EO as antioxidant in sunflower oil. EO also was able to reduce the stable free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH) with a 50% inhibition concentration (IC50) of 20.3 ± 0.9 μg/mL. Therefore, the results indicate that EO could be used as a natural antioxidant in food lipids.

Influence of Growth Phase on the Essential Oil Composition and Antimicrobial Activities of Satureja hortensis

The variations in quantity and quality of essential oils (EOs) from the aerial parts of cultivated Satureja hortensis were determined at different stages of harvesting. The EOs of air-dried samples were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS). The antimicrobial activity of the EOs was investigated by broth microdilution methods. The amount of EOs (w/w, %) were 2.3, 2.5, 2.0, and 1.8% at floral budding, full flowering, immature fruit, and ripened fruit stages, respectively. γ-Terpinene was the major compound of the EO at all developmental stages, except the ripened fruit stage when it was replaced by carvacrol (46.4%). The EOs exhibited strong antibacterial activities against the tested bacteria. Moreover, the EOs either inhibited or killed the examined yeasts at concentrations ranging from 0.03-8.0 μL/mL. Considering the wide range of antimicrobial activities of the examined EOs, they might have potential to be used in the management of infective agents.

Influence of growth phase on the essential oil composition and antimicrobial activities of Satureja hortensis

The variations in quantity and quality of essential oils (EOs) from the aerial parts of cultivated Satureja hortensis were determined at different stages of harvesting. The EOs of air-dried samples were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS). The antimicrobial activity of the EOs was investigated by broth microdilution methods. The amount of EOs (w/w, %) were 2.3, 2.5, 2.0, and 1.8% at floral budding, full flowering, immature fruit, and ripened fruit stages, respectively. gamma-Terpinene was the major compound of the EO at all developmental stages, except the ripened fruit stage when it was replaced by carvacrol (46.4%). The EOs exhibited strong antibacterial activities against the tested bacteria. Moreover, the EOs either inhibited or killed the examined yeasts at concentrations ranging from 0.03-8.0 microL/mL. Considering the wide range of antimicrobial activities of the examined EOs, they might have potential to be used in the management of infective agents.

Chemical composition and antimicrobial activities of the essential oils from three ecotypes of Zataria multiflora

Background:

Zataria multiflora Boiss. is a traditional and popular spice in Iran. The effects of 3 ecotypes (ECTPs) of Z. multiflora essential oils (EOs) against most common causes of food-borne and nosocomial infections were evaluated.

Materials and Methods:

The antimicrobial activities of the EOs were examined by broth microdilution method as recommended by the Clinical and Laboratory Standards Institute (CLSI). The chemical compositions of the EOs from 3 ECTPs of Z. multiflora have been analyzed by gas chromatography–mass spectrometry.

Results:

Analysis of the EOs indicated that 3 chemotypes were present in Z. multiflora, including carvacrol, thymol-carvacrol, and linalool, whereas previous studies have only found carvacrol and thymol. Inhibition studies showed that the tested EOs entirely inhibited the growth of yeasts at concentrations of less than 1 μL/mL. Moreover, the oils exhibited significant bacteriostatic and bactericidal activities against Gram-positive and Gram-negative bacteria at concentrations ranging from 0.12 to 8 μL/mL.

Conclusion:

These results suggest that the EOs from Z. multiflora should be investigated further for possible use in antimicrobial products and food preservatives.