Synergistic antibacterial effects of Moroccan Artemisia herba alba, Lavandula angustifolia and Rosmarinus officinalis essential oils

Synergistic Interaction Effect of Artemisia cina n-hexane Extract and Tagetes lucida Ethyl Acetate Extract on Haemonchus Contortus

PURPOSE

We analysed the possible synergistic activity among active extracts from Artemisia cina and Tagetes lucida combinations on Haemonchus contortus, a nematode parasitising sheep.

METHODS

The work was carried out in vitro on eggs and infective larvae (L3) of H. contortus. The results were analysed with SAS 9.1, applying the ANOVA and Tukey test, and the lethal concentration (LC) values LC50 and LC90 were determined with regression analysis, employing Proc Probit of SAS 9.1. Additionally, the lethal concentration (LC) was calculated with LC50 and LC90 to determine the synergistic effect.

RESULTS

The results demonstrated a high efficacy of the two plants studied on both nematode eggs and L3 larvae as well as of their combinations. The highest egg hatching inhibition was obtained with a 50/50 combination, and the best larvae mortality was obtained with 25% A. cina and 75% T. lucida at 10 mg/mL. Additionally, this combination showed a synergistic effect.

CONCLUSION

The two plant species studied here can be applied as natural anthelmintic alternatives due to their high bioactive effect and synergistic response.

In Vitro Evaluation of Synergistic Essential Oils Combination for Enhanced Antifungal Activity against Candida spp

In recent years, a significant number of infections have been attributed to non-albicidal Candida species (NAC), mainly due to the increasing resistance of NAC to antifungal agents. As only a few antifungal agents are available (azoles, echinocandins, polyenes, allylamines and nucleoside analogues), it is very important to look for possible alternatives to inhibit resistant fungi. One possibility could be essential oils (EOs), which have been shown to have significant antifungal and antibacterial activity. Therefore, in this study, the efficacy of 12 EOs and their combinations was evaluated against four yeasts of the genus Candida (C. albicas, C. glabrata, C. tropicalis and C. parapsilosis). GC-MS and GC-MS FID techniques were used for the chemical analysis of all EOs. VITEK-2XL was used to determine the antifungal susceptibility of the tested Candida spp. strains. The agar disc diffusion method was used for primary screening of the efficacy of the tested EOs. The broth dilution method was used to determine the minimum inhibitory concentrations (MICs) of the most potent EOs. After MIC cultivation, the minimum fungicidal concentration (MFC) was determined on Petri dishes (60 mm). The synergistic effect of combined EOs was evaluated using the checkerboard method and expressed as a fractional inhibitory concentration index (FICI). The results showed that ginger > ho-sho > absinth > dill > fennel > star anise > and cardamom were the most effective EOs. For all Candida species tested, the synergy was mainly observed in these combinations: ginger/fennel for C. albicans FICI 0.25 and C. glabrata, C. tropicalis and C. parapsilosis FICI 0.5 and absinth/fennel for C. albicans FICI 0.3125, C. tropicalis FICI 0.3125 and C. parapsilosis FICI 0.375. Our results suggest that the resistance of fungal pathogens to available antifungals could be reduced by combining appropriate EOs.

Optimization and antifungal efficacy against brown rot fungi of combined Salvia rosmarinus and Cedrus atlantica essential oils encapsulated in Gum Arabic

The stability, sensitivity, and volatility of essential oils are some of their most serious limitations, and nanoencapsulation has been considered one of the most effective techniques for solving these problems. This research aimed to investigate the incorporation of Salvia rosmarinus Speen and Cedrus atlantica Manetti (MEO) essential oil mixture in Gum Arabic (GA) and to evaluate nanoencapsulation's ability to promote antifungal activity against two brown rot fungi responsible for wood decay Gloeophyllum trabeum and Poria placenta. The optimization of encapsulation efficiency was performed using response surface methodology (RSM) with two parameters: solid-to-solid (MEO/GA ratio) and solid-to-liquid (MEO/ethanol). The recovered powder characterization was followed by various techniques using a scanning electron microscope (SEM), X-ray diffractometry (XRD), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and thermo-gravimetric analysis (TGA). The optimal nanoencapsulating conditions obtained from RSM were ratios of MEO/GA of 1:10 (w/w) and MEO/ethanol of 10% (v/v), which provided the greatest encapsulation efficiency (87%). The results of SEM, XRD, DLS, FTIR, and TGA showed that the encapsulation of MEO using GA modified particle form and molecular structure and increased thermal stability. An antifungal activity assay indicated that an effective concentration of MEO had an inhibitory effect on brown rot fungi. It had 50% of the maximal effect (EC50) value of 5.15 ± 0.88 µg/mL and 12.63 ± 0.65 µg/mL for G. trabeum and P. placenta, respectively. Therefore, this product has a great potential as a natural wood preservative for sustainable construction and green building.

Simultaneous Hydrodistillation of Healthy Cedrus atlantica Manetti and Infected by Trametes pini and Ungulina officinalis: Effect on Antibacterial Activity Utilizing a Mixture-Design Method

The Atlas cedar belongs to the Pinaceae family of trees and can be found in a crucial resinous mountain forest in Morocco that spans 133,000 hectares. This endemic species is valued for its wood quality and essential oil (EO), which has various biological activities. However, pathogenic fungi, particularly Trametes pini and Ungulina officinalis, frequently attack Atlas cedarwood, causing significant damage and loss of value. This study aims to extract EO from both healthy and infected Atlas cedarwood to promote its valorization and to assess the antibacterial properties of the resulting EOs. The EOs from healthy and sick cedarwood, as well as a combination of these woods, were extracted using hydrodistillation and simultaneous hydrodistillation. Gas chromatography and mass spectrometry were used to examine the chemical compositions of the EOs. In addition, the disk diffusion method and a measurement of the minimum inhibitory concentration were used to assess the EOs' antibacterial activity against two bacterial strains, namely, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The results show that the extraction yields of healthy cedarwood, cedarwood infected by Trametes pini, and cedarwood infected by U. officinalis were 1.43 ± 0.03, 0.56 ± 0.03, and 0.26 ± 0.06%, respectively, Moreover, the antibacterial results showed that neither the healthy nor the diseased cedar oil had any impact on either strain. However, the EOs from some binary mixtures (75:25, 50:50, and 25:75%) of cedarwood infected by Trametes pini and cedarwood infected by U.ngulina officinalis and the mixture of healthy cedarwood and cedarwood infected by the two fungi inhibited the growth of S. aureus with different MIC values. The findings of this research could lead to the development of new products with antibacterial properties, such as natural disinfectants, and reduce the amount of waste generated by the cedar industry.

Combination of Chemically-Characterized Essential Oils from Eucalyptus polybractea, Ormenis mixta, and Lavandula burnatii: Optimization of a New Complete Antibacterial Formulation Using Simplex-Centroid Mixture Design

This study aims to identify the volatile profile of three essential oils obtained from Eucalyptus polybractea cryptonifera (EPEO), Ormenis mixta (OMEO), and Lavandula burnatii briquet (LBEO) and to examine their combined antibacterial activity that affords the optimal inhibitory ability against S. aureus and E. coli using simplex-centroid mixture design and checkerboard assay. Essential oils (EOs) were isolated by hydrodistillation and characterized using gas chromatography-mass spectrometry (GC-MS) and gas chromatography coupled with flame-ionization detector (GC-FID). The antibacterial activity was performed using disc diffusion and microdilution assays. The chemical analysis revealed that 1,8-cineole (23.75%), p-cymene (22.47%), and α-pinene (11.20%) and p-menthane-1,8-diol (18.19%), α-pinene (10.81%), and D-germacrene (9.17%) were the main components detected in E. polybractea and O. mixta EOs, respectively. However, L. burnatii EO was mainly represented by linalool (24.40%) and linalyl acetate (18.68%). The EPEO, LBEO, and OMEO had a strong antibacterial effect on S. aureus with minimal inhibitory concentrations (MICs) values ranging from 0.25 to 0.5% (v/v). Furthermore, the combination of 1/2048 MICEPEO + 1/4 MICLBEO showed a synergistic antibacterial effect on S. aureus with a FIC index of 0.25, while the formulation of 1/4 MICEPEO + 1/4 MICOMEO demonstrated an antibacterial synergistic activity on E. coli with a FIC index of 0.5. Moreover, the simplex-centroid mixture design reported that the most effective combinations on E. coli and S. aureus correspond to 32%/28%/40% and 35%/30%/35% of E. polybractea, O. mixta, and L. burnatii, respectively. Presented information highlights the action of antibacterial formulations of these EOs and suggests their potential applications as alternatives to commercialized drugs to contract the development of bacteria causing serious infections and food deterioration.

Simultaneous Hydrodistillation of Cedrus atlantica Manetti and Salvia rosmarinus Spenn: Optimization of Anti-Wood-Decay Fungal Activity Using Mixture Design Methodology

Chemical fungicides are often harmful to people and the environment because of their toxicity. The wood protection industry places a high priority on replacing them with natural products. Therefore, this investigation focused on developing a formulation of a binary combination of Salvia rosmarinus Spenn and Cedrus atlantica Manetti obtained by Simultaneous hydrodistillation to protect the wood from decay using a mixture design methodology. The chemical composition of essential oil was identified by gas chromatography coupled with mass spectrometry (GC/MS), and their anti-wood-decay fungal activity was assessed using the macrodilution method against four fungi responsible for wood decay: Coniophora puteana, Coriolus versicolor, Gloeophyllum trabeum, and Poria placenta. The results of GC/MS identified myrtenal as a new component appearing in all binary combinations. The optimum anti-wood-decay fungal activity was observed in a combination of 60% S. rosmarinus and 40% C. atlantica essential oils, providing an effective concentration for 50% of maximal effect (EC50) value of 9.91 ± 1.91 and 9.28 ± 1.55 μg/mL for C. puteana and C. versicolor, respectively. The highest anti-wood-decay fungal activity for G. trabeum and P. placenta was found in the combination of 55% of S. rosmarinus and 45% of C. atlantica essential oils, with EC50 values of 11.48 ± 3.73 and 22.619 ± 3.79 μg/mL, respectively. Combined simultaneous hydrodistillation improved the antifungal effect of these essential oils. These results could be used to improve antifungal activity and protect wood against wood-decay fungi.

Essential Oil of Lavandula officinalis: Chemical Composition and Antibacterial Activities

The purpose of this study was to determine the chemical composition of the essential oil of Lavandula officinalis from Morocco using the GC-MS technique and assess the antibacterial effects against seven pathogenic bacteria strains isolated from the food origins of Salmonella infantis, Salmonella kentucky, Salmonella newport, three serotypes of Escherichia coli (O114H8K11, O127K88ac, O127H40K11) and Klebsiella. Tests of sensitivity were carried out on a solid surface using the Disc Diffusion Method. Results showed that E. coli and S.newport were sensitive to Lavandula officinalis essential oil. Minimum inhibitory concentrations (MIC) were determined using the method of agar dilution. The antibacterial results showed that four strains (three serotypes of E. coli, and S. newport) were remarkedly sensitive to Lavandula officinalis essential oil, giving MIC values of 88.7 µg/mL and 177.5 µg/mL. The molecular docking of the main oil products with the E. coli target protein 1VLY, showed that eucalyptol and linalyl acetate bind efficiently with the active site of the target protein. In particular, eucalyptol showed a higher activity than gentamicin used as positive control with a binding energy of -5.72 kcal/mol and -5.55 kcal/mol, respectively.

Antibacterial activity and synergic effects of the essential oils of Amomum verum Blackw and Zanthoxylum limonella (Dennst.) Alston

The antibacterial activity of Amomum verum Blackw, Zanthoxylum limonella (Dennst.) Alston, Zanthoxylum bungeanum, and Zingiber montanum (J. Koenig) Link ex A. Dietr essential oils were investigated against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa. The essential oils of A. verum Blackw, Z. limonella (Dennst.) Alston, Z. bungeanum, and Z. montanum (J. Koenig) Link ex A. Dietr displayed strong antibacterial activity with a minimum inhibitory concentration and minimumbactericidal concentration ranging from 0.31 to 1.25 µg/mL and 0.62-5.00 µg/mL, respectively. The chemical composition of A. verum Blackw, Z. limonella (Dennst.) Alston, Z. bungeanum, and Z. montanum (J. Koenig) Link ex A. Dietr essential oils were analysed using gas chromatography-mass spectrometry. 1,8-Cineole and limonene were detected in high amounts in the A. verum Blackw and Z. limonella (Dennst.) Alston essential oils, respectively. The major compound in Z. bungeanum and Z. montanum (J. Koenig) Link ex A. Dietr essential oil was 2,4-dimethylether-phloroacetophenone and terpinene-4-ol, respectively. The antibacterial activities and synergistic effects between these essential oils were further analysed. The combination of A. verum Blackw and Z. limonella (Dennst.) Alston essential oils showed a synergistic effect against all bacterial strains, while the other essential oil combinations showed additive, antagonistic effects, and no interaction. The synergistic effect of the combination between A. verum Blackw and Z. limonella (Dennst.) Alston essential oils could be resulted from 1,8-cineole and limonene which was evaluated to possess strong antibacterial activity.

LC-MS/MS and GC/MS Profiling of Petroselinum sativum Hoffm. and Its Topical Application on Burn Wound Healing and Related Analgesic Potential in Rats

Parsley (Petroselinum sativum Hoffm.) is renowned for its ethnomedicinal uses including managing pain, wound, and dermal diseases. We previously highlighted the estrogenic and anti-inflammatory properties of parsley and profiled the phytochemistry of its polyphenolic fraction using HPLC-DAD. To extend our investigation, we here characterized the phytochemical composition of the hydro-ethanolic extract using LC-MS/MS and GC-MS upon silylation, and evaluated the antioxidant, analgesic, antimicrobial, and wound healing activities of its hydro-ethanolic and polyphenolic fraction. The antioxidant property was assessed using FRAP, DPPH, and TAC assays. The antimicrobial activity was tested against four wound infectious microbes (Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans). The analgesic effect was studied using acetic acid (counting the number of writhes) and formalin (recording the licking and biting times) injections while the wound healing activity was evaluated using burn model in vivo. The LC-MS/MS showed that the hydro-ethanolic contains four polyphenols (oleuropein, arbutin, myricetin, and naringin) while GC-MS revealed that it contains 20 compounds including malic acid, D-glucose, and galactofuranoside. The hydro-ethanolic (1000 mg/kg) decreased abdominal writhes (38.96%) and licking time (37.34%). It also elicited a strong antioxidant activity using DPPH method (IC₅₀ = 19.38 ± 0.15 µg/mL). Polyphenols exhibited a good antimicrobial effect (MIC = 3.125-12.5 mg/mL). Moreover, both extracts showed high wound contraction by 97.17% and 94.98%, respectively. This study provides evidence that P. sativum could serve as a source of bio-compounds exhibiting analgesic effect and their promising application in mitigating ROS-related disorders, impeding wound infections, and enhancing burn healing.

Moroccan Endemic Artemisia herba-alba Essential Oil: GC-MS Analysis and Antibacterial and Antifungal Investigation

In Morocco, the endemic Artemisia herba-alba is well known by its traditional uses and health benefits. The search for natural, safe, and effective antibacterial and antifungal agents from plants is in high demand due to microbial and fungal resistance to conventional synthetic antibiotics and antifungal drugs. In this study, the A. herba-alba was collected from the region of Fez-Boulemane during the periods of March, June, and September. Essential oils (EOs) were extracted from the aerial part of the plant by the hydrodistillation method. The chemical constituents were determined using GC-MS as analytical tools. The antimicrobial activities of different oils were tested using the macrodilution method. The results showed the difference in the yields between the three EOs (0.49, 1.74, 1.30% (mL/100 g)), respectively, as well as in their corresponding chemical compositions. The main constituents revealed by GC-MS are higher contents of oxygenated monoterpenes (84.7, 84.4, 81%), such as cis chrysanthenyl acetate (30, 26.7, 27.6%), β-thujone (23.2, 12.9, 15.4%), camphor (9.76, 14.3, 15.8%), chrysanthenone (2.4, 1, 14%), 1,8-cineole (1.5, 11.7, 11.8%), trans β-dihydroterpineol (7.8, 7.2, 6.9%), α-thujone (4.8, 3, 5.4%), and sesquiterpenic davanone (3.9, 1.5, 1.4%), respectively. The three EOs biological activities’ results showed significant antimicrobial effects against four bacteria tested (E. coli, B. subtilis, S. aureus, M. luteus), with the MIC values ranging from 0.1 to 0.03% (v/v), as well as interesting antifungal effects on both wood rot fungi against four fungi examined (G. trabeum, P. placenta, C. puteana, C. versicolor) and molds against three microorganisms tested (A. niger, P. digitatum, P. expansum), with MIC values ranging from 0.2 to 0.03% (v/v) and 0.4 to 0.03% (v/v), respectively. The June and September EO samples showed more potent activities than those collected during March. Our research findings showed quantitative variability in both EO contents and chemical compositions, which could be due to the phenological stages, climatic conditions of growth, and harvesting periods. The potent results of the antimicrobial/antifungal activities were provided by the EOs of June and September and might be correlated to the contribution and synergism effect of all oxygenated monoterpenes. These results support the possible application of A. herba-alba EOs as natural and safe antibacterial agents, and an effective alternative to synthetic drugs, enabling the prevention and treatment of certain pathogenic infections in food and health, and the preservation of wood alteration against fungi.

Potential of plant secondary metabolite-based polymers to enhance wound healing

There is a global epidemic of non-healing wounds. Chronic inflammation, overexpression of pro-inflammatory cytokines, oxidative stress and bacterial infection are implicated in delayed wound healing. Natural extracts are a rich source of bioactive molecules called plant secondary metabolites (PSMs) that include terpenes and phenols. These molecules may facilitate wound healing through their antioxidant, anti-inflammatory, and antibacterial activity. After briefly outlining the process of wound healing and how it is compromised in chronic wounds, this review focuses on investigating how PSMs-based polymers may improve wound healing. Best methods for incorporating PSMs into wound dressings are reviewed and critically compared. The exiting body of literature strongly suggests that PSMs-based polymers incorporated into wound dressings could have clinical value in aiding wound healing. STATEMENT OF SIGNIFICANCE: Chronic wounds develop by the persistence of inflammation, oxidative stress and infection. Chronic wounds affect the worldwide population, by reducing quality of life of patients with significant cost to healthcare systems. To help chronic wounds to heal and overcome this burden, materials with anti-inflammatory, antioxidant and antibacterial properties are required. Plant secondary metabolites (PSMs) are volatile materials that have all these properties. PSMs-based polymers can be fabricated by polymerization techniques. The present review provides an overview of the state-of-the-art of the wound healing mechanisms of PSMs. Current developments in the field of PSMs-based polymers are reviewed and their potential use as wound dressings is also covered.

Chemometric Investigation and Antimicrobial Activity of Salvia rosmarinus Spenn Essential Oils

To ensure the better production and sustainable management of natural resources, a chemometric investigation was conducted to examine the effect of cooperative and harvesting periods on the crop yields and chemical compositions of Salvia rosmarinus Spenn essential oils in the Oriental region of Morocco. The samples were collected from three cooperatives over nine time periods from January 2018 to April 2019. The chemical composition of Salvia rosmarinus Spenn essential oils was analyzed by gas chromatography coupled with mass spectrometry. The data from this study were processed by multivariate analyses, including principal component analysis (PCA) and hierarchical cluster analysis (HCA). The disc diffusion technique and a determination of the minimal inhibitory concentration were performed to study the antibacterial properties of the oils. Statistical analysis showed that the cooperative and harvest period have a significant effect on yields. The highest yield of essential oil was recorded in April 2019 at cooperative C1. The PCA and the HCA results were divided into two groups: Group A for the summer season and group B for the winter season. The samples collected during summer were characterized by a high amount of 1,8-cineole component and a high yield of essential oil, whereas the samples collected during winter were qualified by a high amount of α-pinene component and a low yield of essential oil. The antibacterial activity of Salvia rosmarinus Spenn essential oils showed that Mycobacterium smegmatis ATCC23857 and Bacillus subtilis ATCC 23857 are the most susceptible strains, stopping growth at 1/500 (v/v). The least susceptible strain is Escherichia coli ATCC25922, with an MIC value corresponding to 1/250 (v/v). The findings of this study could have a positive economic impact on the exploitation of rosemary in the Oriental region, especially during the best harvest periods, as they indicate how to obtain the best yields of oils richest in 1,8-cineole and α-pinene chemotypes.

Unassisted and Carbon Dioxide-Assisted Hydro- and Steam-Distillation: Modelling Kinetics, Energy Consumption and Chemical and Biological Activities of Volatile Oils

The demand for more suitable eco-friendly extraction processes has grown over the last few decades and driven research to develop efficient extraction processes with low energy consumption and low costs, but always assuring the quality of the volatile oils (VOs). The present study estimated the kinetic extraction and energy consumption of simultaneous hydro- and steam-distillation (SHSD), and SHSD assisted by carbon dioxide (SHSDACD), using an adopted modelling approach. The two isolation methods influenced the VOs yield, chemical composition and biological activities, namely, antioxidant, anti-glucosidase, anti-acetylcholinesterase and anti-inflammatory properties. SHSDACD provided higher VOs yields than the SHSD at a shorter extraction time: 2.8% at 30 min vs. 2.0% at 120 min, respectively, for Rosmarinus officinalis, 1.5% at 28 min vs. 1.2% at 100 min, respectively, for Lavandula angustifolia, and 1.7% at 20 min vs. 1.6% at 60 min, respectively, for Origanum compactum. The first order and sigmoid model fitted to SHSD and SHSDACD, respectively, with R2 value at 96% and with mean square error (MSE) < 5%, where the k distillation rate constant of SHSDACD was fivefold higher and the energy consumption 10 times lower than the SHSD. The rosemary SHSD and SHSDACD VOs chemical composition were similar and dominated by 1,8-cineole (50% and 48%, respectively), and camphor (15% and 12%, respectively). However, the lavender and oregano SHSDACD VOs were richer in linalyl acetate and carvacrol, respectively, than the SHSD VOs. The SHSDACD VOs generally showed better capacity for scavenging the nitric oxide and superoxide anions free radicals as well as for inhibiting α-glucosidase, acetylcholinesterase, and lipoxygenase.

Simultaneous Hydrodistillation-Steam Distillation of Rosmarinus officinalis, Lavandula angustifolia and Citrus aurantium from Morocco, Major Terpenes: Impact on Biological Activities

Interest in the use of essential oils (EOs) in the biomedical and food industries have seen growing over the last decades due to their richness in bioactive compounds. The challenges in developing an EO extraction process that assure an efficient levels of monoterpenes with impact on biological activities have driven the present study, in which the EO extraction process of rosemary, lavender and citrus was performed by simultaneous hydrodistillation-steam distillation, and the influence of EO composition on biological activities, namely antioxidant, anti-inflammatory, antidiabetic, anti-acetylcholinesterase, anti-tyrosinase, antibacterial, and antibiofilm activity, were evaluated. The EO yields of combinations were generally higher than the individual plants (R. officinalis (Ro), L. angustifolia (La), and C. aurantium (Ca)) extracted by the conventional hydrodistillation. The EOs obtained by this process generally had a better capacity for scavenging the free radicals, inhibiting α-glucosidase, and acetylcholinesterase activities than the individual EOs. The combination of EOs did not improve the ability for scavenging peroxide hydrogen or the capacity for inhibiting lipoxygenase activity. The antioxidant activity or the enzyme inhibition activity could not only be attributed to their major compounds because they presented lower activities than the EOs. The chemical composition of the combination Ro:La:Ca, at the ratio 1/6:1/6:2/3, was enriched in 1,8-cineole, linalool, and linalyl acetate and resulted in lower MIC values for all tested strains in comparison with the ratio 1/6:2/3:1/6 that was deprived on those components. The biofilm formation of Gram positive and Gram negative bacteria was impaired by the combination Ro:La:Ca at a sub-inhibitory concentration.

Multidisciplinary Studies of Folk Medicine "Five Thieves' Oil" (Olejek Pięciu Złodziei) Components

To meet the growing interest in natural antibacterial agents, we evaluated the physicochemical and biological properties of the folk medicine known as “five thieves’ oil” (Polish name: olejek pięciu złodziei). Five thieves’ oil consists of a mixture of five oils: rosemary, lemon, clove, eucalyptus, and cinnamon. In this study, we performed gas chromatography, FTIR, and UV–vis spectroscopic analysis, as well as L-a-b color tests, contact angle determination, and surface tension determination. To verify its antibacterial activity, the metabolic activity and changes in cell membrane permeability of bacteria of the genus Pseudomonas were studied. As a result, it was found that among the constituent oils, the oils of clove and cinnamon were the least volatile and, at the same time, had the strongest antibacterial activity. However, a mix of all the oils also showed comparable activity, which was even more pronounced for the oils after 4 weeks of aging. This effect can be linked to the high content of terpene derivatives such as eugenol and cinnamaldehyde, which can cause changes in bacterial membrane permeability, affecting cell activity and survival. This study is the first to characterize the constituents of the popular folk medicine five thieves’ oil, confirming and explaining its strong antibacterial activity, thus constituting a significant contribution to contemporary health education.

Combination Therapy Involving Lavandula angustifolia and Its Derivatives in Exhibiting Antimicrobial Properties and Combatting Antimicrobial Resistance: Current Challenges and Future Prospects

Antimicrobial resistance (AMR) has been identified as one of the biggest health threats in the world. Current therapeutic options for common infections are markedly limited due to the emergence of multidrug resistant pathogens in the community and the hospitals. The role of different essential oils (EOs) and their derivatives in exhibiting antimicrobial properties has been widely elucidated with their respective mechanisms of action. Recently, there has been a heightened emphasis on lavender essential oil (LEO)’s antimicrobial properties and wound healing effects. However, to date, there has been no review published examining the antimicrobial benefits of lavender essential oil, specifically. Previous literature has shown that LEO and its constituents act synergistically with different antimicrobial agents to potentiate the antimicrobial activity. For the past decade, encapsulation of EOs with nanoparticles has been widely practiced due to increased antimicrobial effects and greater bioavailability as compared to non-encapsulated oils. Therefore, this review intends to provide an insight into the different aspects of antimicrobial activity exhibited by LEO and its constituents, discuss the synergistic effects displayed by combinatory therapy involving LEO, as well as to explore the significance of nano-encapsulation in boosting the antimicrobial effects of LEO; it is aimed that from the integration of these knowledge areas, combating AMR will be more than just a possibility.

An overview on ethnobotanico-pharmacological studies carried out in Morocco, from 1991 to 2015: Systematic review (part 1)

ETHNOPHARMACOLOGICAL RELEVANCE

The full bibliometric records of data retrieved from ethnobotanical field studies carried out in Morocco (1991-2015) was quali-quantitatively analysed. Despite the importance of traditional medicinal uses in Morocco, any comments about the methodologies and approaches adopted by reviewed studies have been undertaken. Include more data about the importance of traditional medicinal uses in Morocco.

AIM OF THE STUDY

Three key points were targeted in this review: (i) to contribute to original compilation of medicinal plants traditionally used by people at whole Morocco, by gathering and documenting the current status of these ancestral medical practices, (ii) to provide a novel insight into the relationship between local and biomedical disease concepts in Moroccan society, taking into account health-related beliefs, and their influences on medicinal plant uses, (iii) to figurout the weaknesses and the strengths of the conceptual approches and methods adopted by researchers in ethnobotanical field works.

MATERIALS AND METHODS

With the help of a computerized database querying, we conducted an extensive literature search respecting our integration criteria. We performed this bibliographic research by using the following search engines available over the Web: Google Scholar, PUBMED, Sciencedirect, Current Content Connect, SCOPUS, SPRINGER LINK, GLOBAL PLANTS, Cochrane Library and SCIRUS. The scientific names listed in the present paper have been validated according to the "The Plant List" and the African Plants Database in order to standardize ethnobotanical data on an international level. For the analysis of data gathered, quali-quantitative analyses have been performed.

RESULTS

A total of 905 medicinal plant species belonging to 116 families and 726 genera have been selected from 63 published articles. The dominant families were ASTERACEAE (111 species) followed by the FABACEAE (77 species), LAMIACEAE (75 species) and APIACEAE (46 species). The plant species listed are used to cure several public ailments. The digestive ailments represented the most important category (494 species) followed by dermatological diseases (407 species), diabetes (315 species) and urinary diseases (277 species). We assigned the importance of the plant species by several measures (including Frequency Cited (FC), Number of Uses (NU), Number of Respondents (NR) and Index of Performance (IP). The ICF (Informant Consensus Factor) calculated was important in all categories of diseases averaging 47%.

CONCLUSION

The results obtained, which cover the whole country, delineate the profile of rich wealth of indigenous knowledge on traditional uses of medicinal plants heald by Moroccan society. The total number of 905 plant species listed in this paper, are currently being utilized as medicines and the number is expected to grow as infrastructure allows greater access to unexplored parts of the country. Furthermore, the know how, regarding the plants used, is consistent because the ICF has recorded important values for most diseases treated. Furthermore, in the present paper, we suggested, for authors, some useful recommendations for ethnobotanical field works such as the respect of ethnobotanical standards including checklist of plants with international data base, the deposited voucher specimens, sampling and collection methods.

Phenolic Composition, Antioxidant Capacity and Antibacterial Activity of White Wormwood (Artemisia herba-alba)

Artemisia herba-alba Asso. (Wormwood) is a wild aromatic herb that is popular for its healing and medicinal effects and has been used in conventional as well as modern medicine. This research aimed at the extraction, identification, and quantification of phenolic compounds in the aerial parts of wormwood using Soxhlet extraction, as well as characterizing their antimicrobial and anitoxidant effects. The phenolic compounds were identified in different extracts by column chromatography, thin layer chromatography (TLC), and high performance liquid chromatography. Five different fractions, two from ethyl acetate extraction and three from ethanolic extraction were obtained and evaluated further. The antimicrobial activity of each fractions was evaluated against two Gram-positive (Bacillus cereus and Staphylococcus aureus) and two Gram-negative microorganisms (Escherichia coli and Proteus vulgaris) using the disc-diffusion assay and direct TLC bioautography assay. Fraction I inhibited B. cereus and P. vulgaris, Fraction II inhibited B. cereus and E. coli, Fraction III inhibited all, except for P. vulgaris, while Fractions IV and V did not exhibit strong antimicrobial effects. Their antioxidant capabilities were also measured by calculating their ability to scavenge the free radical using DPPH method and the ferric reducing antioxidant power (FRAP) assay. Ethanolic fractions III and V demonstrated excellent antioxidant properties with IC50 values less than 15.0 μg/mL, while other fractions also had IC50 values less than 80.0 μg/mL. These antioxidant effects were highly associated with the number of phenolic hydroxyl group on the phenolics they contained. These extracts demonstrated antimicrobial effects, suggesting the different phenolic compounds in these extracts had specific inhibitory effects on the growth of each bacteria. The results of this study suggested that the A. herba-alba can be a source of phenolic compounds with natural antimicrobial and antioxidant properties which can be used for potential pharmaceutical applications.

A Current Perspective of Plants as an Antibacterial Agent: A Review

With the emergence and evolution of bacterial strains, it is now becoming difficult for pharmaceutical industries to provide remedies required for the betterment of mankind. Continuous exposure with available medication leads to the development of new strains with a significant amount of resistance, due to which pharmaceutical industries are facing various challenges. Antimicrobial resistance is the phenomenon causing a challenge in new drug development through conventional methods. Therefore, the requirement of alternative medicine is in high demand. Recently, allopathic medicines have seen a disinterest and people are preferring natural solutions due to their fewer side effects comparable to conventional medicine. Worldwide plants are utilized for various disease treatments such as bacterial infection, skin disorders, cancer, asthma, respiratory problems, etc. The presence of a wide range of phytocompounds in different plants provides an alternative to the pharmaceutical industries to counter the problem of bacterial infections. Different plants contain various phytochemicals that possess numerous therapeutic activities and provide a remedy to suppress various bacterial strains. Therefore, in this review, an overview of various plants and their phytocompounds which are responsible for antibacterial activity has been discussed.

Antibacterial, Antifungal, Antimycotoxigenic, and Antioxidant Activities of Essential Oils: An Updated Review

The interest in using natural antimicrobials instead of chemical preservatives in food products has been increasing in recent years. In regard to this, essential oils-natural and liquid secondary plant metabolites-are gaining importance for their use in the protection of foods, since they are accepted as safe and healthy. Although research studies indicate that the antibacterial and antioxidant activities of essential oils (EOs) are more common compared to other biological activities, specific concerns have led scientists to investigate the areas that are still in need of research. To the best of our knowledge, there is no review paper in which antifungal and especially antimycotoxigenic effects are compiled. Further, the low stability of essential oils under environmental conditions such as temperature and light has forced scientists to develop and use recent approaches such as encapsulation, coating, use in edible films, etc. This review provides an overview of the current literature on essential oils mainly on antifungal and antimycotoxigenic but also their antibacterial and antioxidant activities. Additionally, the recent applications of EOs including encapsulation, edible coatings, and active packaging are outlined.