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Antimicrobial activity of five essential oils from lamiaceae against multidrug-resistant Staphylococcus aureus
Abstract and Figures
Analysis of Lamiaceae essential oils (EOs) by GC-FID-MS revealed the presence as the major constituents of linalool (16.8%), linalyl acetate (15.7%) in Lavandula angustifolia, menthol (29.0%), menthone (22.7%), menthyl acetate (19.2%) in Mentha x piperita, terpinen-4-ol (27.1%), (E)-sabinene hydrate (12.1%), γ-terpinene (10.0%) in Origanum majorana, α-thujone (19.5%), camphor (19.0%), viridiflorol (13.5%) in Salvia officinalis, thymol (61.9%), p-cymene (10.0%), γ-terpinene (10.0%) in Thymus vulgaris. Based on the MIC and MBC values (0.09–0.78 mg/mL) and ratio MBC/MIC showed that EO from T. vulgaris (TO) had the strong inhibitory and bactericidal effect against multidrug-resistant Staphylococcus aureus. The bacterial cells were total killed by TO at 2MIC concentration after 6 h. The higher concentrations of other EOs were needed to achieve bactericidal effects. The strong bactericidal effect of TO against these bacteria indicates the possibility of topical use of TO but it requires research under clinical conditions.
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... A very effective replacement for t h e nitrates in meat products can be TEOs with very strong antilisterial effects [56]. TEO has been used to treat wound infections as an antibacterial agent in oral hygiene [57]. Due to the presence of menthol and menthone in MEO, it manifests a significant antimicrobial activity against S. aureus, M. flavus, B. subtilis, Figure 9. Bi-plot of principal component analysis of antimicrobial potential of essential oils E coli; P vulgaris; B. subtilis; S. aureus; and C. albicans. ...
... TEO has been used to treat wound infections as an antibacterial agent in oral hygiene [56]. Due to the presence of menthol and menthone in MEO, it manifests a significant antimicrobial activity against S. aureus, M. flavus, B. subtilis, S. enteritidis, and S epidermidis [57]. MEO possesses a strong activity against C. albicans with inhibition zones ranging from 38.0 to 45.0 mm and, together with TEO, showed much larger inhibition zones (16.0-30.0 ...
Thyme, mint, and lemon balm were used to determine whether shading conditions could improve the yield, composition, antioxidant, and antimicrobial activity in plant essential oils (EOs) in comparison with non-shaded plants from an open field. The yield of the EOs of non-shaded thyme, mint, and lemon balm, was 3.44, 3.96, and 0.21 mL/100 g, respectively. Plants covered by nets produced different levels of EOs (3.46, 2.20, and 0.45 mL/100 g) after 120 min of hydrodistillation. The main components of the thyme essential oil are thymol (44.2–43.9%), γ-terpinene (18.3–16.8%), and p-cymene (16.5–17.4%). The predominant components of mint essential oil are piperitenone oxide (52.6–64.8%) and 1,8 cineole (25.9–16.3%), while lemon balm essential oil consists of the following main components: geranial (34.0–32.8%); neral (21.3–24.9%); and piperitenone oxide (17.2–16.7%). The EOs from non-shaded thyme and mint plants have the highest antioxidant activity (EC50 value 0.54 mg/mL and 3.03 mg/mL). However, shaded lemon balm showed a stronger antioxidant activity (EC50 3.43 mg/mL) than non-shaded plants (12.85 mg/mL) after 60 min of incubation. The EOs from all plants showed significant effects against Escherichia coli, Proteus vulgaris, Bacillus subtilis, Staphylococcus aureus, and Candida albicans. The most active EOs against most of the isolates originated from Thymus vulgaris L., plants. Adequate cultivation techniques, such as shading for Lamiaceae plants, has positive effects, especially in Melissa officinalis L. Shading can achieve a higher content and components in terms of the specific biological activity (antioxidant and microbial) of EOs.
... At times, the PSMs can affect the sensing system within the bacterial community and thereby inhibit biofilm formation [50][51][52]. Importantly, many secondary metabolites generate ROS that can induce enzymatic oxidative stress responses in a bacterial cell [53,54]. ...
The emergence of antibiotic resistant microorganisms possesses a great threat to human health and the environment. Considering the exponential increase in the spread of antibiotic resistant microorganisms, it would be prudent to consider the use of alternative antimicrobial agents or therapies. Only a sustainable, sustained, determined, and coordinated international effort will provide the solutions needed for the future. Plant secondary metabolites show bactericidal and bacteriostatic activity similar to that of conventional antibiotics. However, to effectively eliminate infection, secondary metabolites may need to be activated by heat treatment or combined with other therapies. Cold atmospheric plasma therapy is yet another novel approach that has proven antimicrobial effects. In this review, we explore the physiochemical mechanisms that may give rise to the improved antimicrobial activity of secondary metabolites when combined with cold atmospheric plasma therapy.
... Labiatae EOs contain many aliphatic compounds, aromatic compounds, and terpene derivatives [47]. Previous studies have shown that the EOs of Labiatae plants can inhibit a wide range of bacteria and fungi [30][31][32]. In this study, we evaluated the inhibitory effects of O. vulgare, T. mongolicus, and P. cablin EOs on the root rot pathogen of A. chinensis. ...
Atractylodes chinensis has a high medicinal value and is widely cultivated. However, root rot disease seriously affects the yield and quality of A. chinensis. To develop green and safe pesticides, the inhibitory effect of essential oils (EOs) of three Labiatae plants on the pathogenic fungi that causes root rot disease in Atractylodes chinensis was investigated. The results showed that the Origanum vulgare EO and Thymus mongolicus EO exhibited strong inhibitory effects on Fusarium oxysporum, Fusarium solani, and Fusarium redolens, with 100% inhibition rate. The low MIC values of EOs and their main components against the three pathogenic fungi indicated that all of them showed strong fungicidal effects. The MIC values of O. vulgare EO against F. oxysporum, F. solani, and F. redolens were 2.60 mg/mL, 3.13 mg/mL, and 1.56 mg/mL, respectively. Analyses using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the O. vulgare EO severely damaged the cell wall and cell membrane of mycelial cells. The O. vulgare EO increased cell permeability, leading to a large leakage of cell contents (DNA and proteins). In addition, O. vulgare EO inhibited F. oxysporum by inducing ROS production and reducing the amount of intracellular GSH, leading to a large accumulation of ROS. This study showed that plant EOs have excellent fungicidal activity and can be used as novel natural and environmentally friendly pesticides for the control of root rot in A. chinensis.
... Salvia officinalis [52,[61][62][63][64][65][66][67][68], Cistus monspeliensis [69][70][71][72], Cistus salviifolius [69,71], Origanum vulgare [70,, and Myrtus communis [19,[108][109][110][111][112][113][114][115][116][117][118][119][120] showed an average MIC against S. aureus of respectively 0.46 (±0.56) mg/mL, 0.72 (±0.78) mg/mL, 0.831 (±1.033) mg/mL, 0.997 (±3.24), and 0.736 (±1.32). ...
Antimicrobial resistance (AMR) has emerged as a global health crisis, necessitating the search for innovative strategies to combat infectious diseases. The unique biodiversity of Italian flora offers a treasure trove of plant species and their associated phytochemicals, which hold immense potential as a solution to address AMR. By investigating the antimicrobial properties of Italian flora and their phytochemical constituents, this study aims to shed light on the potential of phyto-complexes as a valuable resource for developing novel or supportive antimicrobial agents useful for animal production.
... Durante el proceso de las revisiones de diferentes artículos, diversos estudios demuestran una alta eficacia antibacteriana del Thymus vulgaris frente a Staphylococcus aureus. Por ejemplo: kovacevic et al (18) encontró una concentración mínima inhibitoria desde 0,39 a 3,125 mg/ml, Kot et al (19) mostró una concentración mínima de 0,09 a 0,19 mg/ml, Cáceres et al (20) encontró un diámetro de zona inhibitoria 24-35mm y Rinaldi et al (20) encontró una CMI de 0,125mg/ml. Siendo estudios a base de nanoemulsión, extractos de Thymus vulgaris se correlaciona que la planta posee actividad antibacteriana. ...
Introducción: El uso irracional de antibióticos es un problema de salud publica, teniendo en el Thymus vulgaris una alternativa potencial por su actividad antibacteriana. Objetivo: Revisar la bibliografía existente acerca de la actividad antibacteriana in vitro del Thymus vulgaris frente a cepas de Escherichia coli y Staphylococcus aureus . Método: Se realizó una revisión bibliográfica de estudios in vitro con preparados de aceite esencial del Thymus vulgaris que permitan responder la pregunta planteada, que se hayan publicado en los últimos 6 años. La búsqueda se hizo en el buscador PubMed y se extrajeron, de cada estudio, el valor del halo de inhibición (HI) y la concentración mínima inhibitoria (CMI). Resultados: Se identificaron un total de 105 estudios, de los cuales fueron seleccionados 8 para revisión final. De esos, cinco evaluaban la actividad sobre Staphylococcus aureus con HI de 8mm a 30mm y CMI de 2 a 160 ug/ml. Seis estudios evaluaban la actividad sobre Escherichia coli con HI de 19,66 a 37mm y CMI de 0,33 a 160 ug/ml. Conclusión: Existe evidencia de que el aceite esencial de Thymus vulgaris tiene actividad antibacteriana in vitro ante cepas de Escherichia coli y Staphylococcus aureus.
... [22], and these values are close to our data. o-Cymene prevailed among the terpenes in our samples, while other researchers [21,41,44,45,53] distinguished p-cymene as the main terpene. β-Caryophyllene and γ-terpinene contents were in line with those given for the essential oils of Thymus vulgaris L. obtained by hydrodistillation using a Dering-type apparatus [41] and commercial samples [44]. ...
Plants of the Lamiaceae family have been used for thousands of years in cooking, as well as phyto- and aromatherapy. Their essential oils are characterized by high antioxidant and other types of biological activities. In our study, the phytochemical profile and quantification of the essential oil components of thyme, marjoram, and sage were analyzed by gas chromatography with mass-spectrometric detection (GC-MSD). The antioxidant properties of the samples were evaluated using total antioxidant parameters (total antioxidant capacity (TAC), ferric reducing power (FRP), antioxidant activity (AOA) towards 2,2-diphenyl-1-picrylhydrazyl (DPPH•), and total phenolics by Folin–Ciocalteu method). The obtained FRP was 46–321-fold lower than TAC, which is consistent with the contents of phenolics identified in the samples. Terpenes, isopropylmethylphenols, and eugenol turned out to be the major components of all essential oils and determined their TAC and AOA. The Folin–Ciocalteu method was applicable to the thyme essential oil only. Its FRP, which is based on the reaction of phenolic antioxidants with electrogenerated ferricyanide ions, agreed well with the total phenolic contents (329 ± 17 and 334 ± 15 mg of carvacrol per mL, respectively). The thyme essential oil had the highest antioxidant parameters, while sage showed the weakest antioxidant properties. Positive correlations (r = 0.8846–0.9964) of the antioxidant parameters were obtained.
... 39 A complex essential oil distillate (Olbas®, Tropfen) with the main component of 1.8-cineol, menthol and menthone displayed a high antimicrobial activity against MRSA, and peppermint oil was the most potent of all individual essential oils tested in a time-kill study. 11 Moreover, the EO from Mentha x piperita with the major constituents of menthone (22.7%) effectively inhibited growth of multidrug-resistant S. aureus strains isolated from clinical materials from humans, although the MIC values showed a wide range from 0.39 mg/mL to 3.12 mg/mL 40 Our results indicated that the antimicrobial activity of menthone against MRSA were weaker than several common phenolic EO compounds such as hinokitio, thymol, carvacrol, and menthol, 41 but comparable to 1.8-cineole. 42 The antibacterial mechanism of essential oils containing menthone was rarely reported. ...
Objective:
The characteristic constituents of essential oils from aromatic plants have been widely applied as antimicrobial agents in the last decades. However, their mechanisms of action remain obscure, especially from the metabolic perspective. The aim of the study was to explore the antimicrobial effect and mechanism of menthone, a main component of peppermint oil, against methicillin resistant Staphylococcus aureus (MRSA).
Methods:
An integrated approach including the microbiology and the high-coverage lipidomics was applied. The changes of membrane properties were studies by the fluorescence and electron microscopical observations. The lipid profile was analyzed by ultra-high performance liquid chromatography coupled with quadruple Exactive mass spectrometry (UHPLC-QE-MS). The lipid-related key targets which were associated with the inhibitory effect of menthone against MRSA, were studied by network analysis and molecular docking.
Results:
Menthone exhibited antibacterial activities against MRSA, with minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of 3,540 and 7,080 μg/mL, respectively. The membrane potential and membrane integrity upon menthone treatment were observed to change strikingly. Further, lipids fingerprinting identified 136 significantly differential lipid species in MRSA cells exposed to menthone at subinhibitory level of 0.1× MIC. These metabolites span 30 important lipid classes belonging to glycerophospholipids, glycolipids, and sphingolipids. Lastly, the correlations of these altered lipids, as well as the potential metabolic pathways and targets associated with menthone treatment were deciphered preliminarily.
Conclusion:
Menthone had potent antibacterial effect on MRSA, and the mechanism of action involved the alteration of membrane structural components and corresponding properties. The interactions of identified key lipid species and their biological functions need to be further determined and verified, for the development of novel antimicrobial strategies against MRSA.
Nowadays, antibacterial resistance to synthetic antibiotics has become a big issue worldwide. Mentha piperita essential oil (EO) and its bioactive components with antibacterial, antibiofilm, and antioxidant properties are recommended for the treatment of microbial infections in traditional medicine. This study aimed to detect phytochemical components, antioxidant and cytotoxic activity; to evaluate antibacterial and antibiofilm effects of M. piperita EO on strains. Gas chromatography/mass spectrometry (GC-MS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) tests were used to determine chemical composition, antioxidant and cytotoxic potentials of EO, respectively. Antibacterial activity was carried out through disc diffusion and minimum inhibitory concentration (MIC) assays. The biofilm biomass of bacteria was determined by the crystal violet (CV) staining method. Menthone (27.28%), L-menthol (23.71%), and limonene (7.48%) were the main components. M. piperita EO was found to have strong antibacterial activity with the MIC-MBC values in the range of 0.125-16.00% (v/v) and moderate antioxidant activity. The peppermint EO showed an antibiofilm effect on all strains and a cytotoxic effect on NIH 3T3 cells. M. piperita EO may be used alone or in combination with antibiotics or carrier oils as a therapeutic agent against bacterial infections. Further in vivo experiments should be carried out to detect a safe dosage of EO.
Plant extracts and essential oils (EOs) are characterized by their antibacterial properties against various bacterial pathogens, including staphylococci. Some strains of these bacteria are resistant against the adverse effects of the environment including antibiotics, e. g. methicillin-resistant Staphylococcus aureus (MRSA). EOs alone cannot substitute for antibiotics but their treatment may be useful to intensify and strengthen the effects of antibiotics on pathogenic staphylococci. In this work, we tested the antibacterial effects of the essential oils of Mentha species with menthol as one of the effective substances against different strains of S. aureus. Two in vitro methods were used, the qualitative disc diffusion assay and the quantitative minimal inhibitory concentration (MIC) of selected essential oils. Peppermint oil from Mentha piperita, spearmint oil from Mentha spicata var. crispa and cornmint oil from Mentha arvensis were tested in this study against the various strains of Staphylococcus aureus, including methicillin resistant Staphylococcus aureus (MRSA). The oils were dissolved in DMSO (dimethyl sulfoxide) and diluted at the following ratios: 1 : 1, 1 : 2, 1 : 5, and 1 : 10. Based on the results determined by the agar disc diffusion test, the highest antibacterial properties were observed in spearmint oil against S. aureus CCM 4223 at 1 : 2 ratio where the inhibition zone varied at a range of 35.67 ± 6.81 mm. We determined also the MIC of all the oils where concentrations of the oils were as follows: 1 %; 0.5 %; 0.25 %; 0.125 % and 0.0625 %. The lowest concentrations of essential oils that possessed inhibitory effects on the growth of S. aureus varied between 0.125 % and 0.25 %.
Herbs and spices have been used since ancient times to improve the sensory characteristics of food, to act as preservatives and for their nutritional and healthy properties. Herbs and spices are generally recognized as safe (GRAS) and are excellent substitutes for chemical additives. Essential oils are mixtures of volatile compounds obtained, mainly by steam distillation, from medicinal and aromatic plants. They are an alternative to synthetic additives for the food industry, and they have gained attention as potential sources for natural food preservatives due to the growing interest in the development of safe, effective, natural food preservation. Lamiaceae is one of the most important families in the production of essential oils with antioxidants and antimicrobial properties. Aromatic plants are rich in essential oils and are mainly found in the Mediterranean region, where the production of such oils is a profitable source of ecological and economic development. The use of essential oils with antimicrobial and antioxidant properties to increase the shelf life of food is a promising technology, and the essential oils of the Lamiaceae family, such as rosemary, thyme, and sage, have been extensively studied with respect to their use as food preservatives. Regarding the new applications of essential oils, this review gives an overview of the current knowledge and recent trends in the use of these oils from aromatic plants as antimicrobials and antioxidants in foods, as well as their biological activities, future potential, and challenges.
The paper focuses on the in vitro antimicrobial activity of Lavandula angustifolia Mill. (lavender) essential oil in combination with four commercial antimicrobial agents. Stock solutions of chloramphenicol, ciprofloxacin, nystatin, and fusidic acid were tested in combination with L. angustifolia essential oil. The antimicrobial activities of the combinations were investigated against the Gram-positive bacterial strain Staphylococcus aureus (ATCC 6538) and Gram-negative Pseudomonas aeruginosa (ATCC 27858) and Candida albicans (ATCC 10231) was selected to represent the yeasts. The antimicrobial effect was performed using the minimum inhibitory concentration (MIC) microdilution assay. Isobolograms were constructed for varying ratios. The most prominent interaction was noted when L. angustifolia essential oil was combined with chloramphenicol and tested against the pathogen P. aeruginosa (ΣFIC of 0.29). Lavendula angustifolia essential oil was shown in most cases to interact synergistically with conventional antimicrobials when combined in ratios where higher volumes of L. angustifolia essential oil were incorporated into the combination.
The aim of this study was to investigate antibacterial effects of oregano and thyme essential oils (EOs) on some food-borne bacteria. GC-MS analysis of EOs was performed in order to determine their composition and phenols were predominant constituents. The investigation of the antibacterial effects of EOs was performed on Salmonella Enteritidis, Salmonella Thyphimurium, Staphylococcus aureus, methicillin resistant Staphylococcus aureus, Escherichia coli and Bacillus cereus, and MICs were determined by broth microdilution method. EOs exhibited antibacterial activity against all tested microorganisms.
Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) due to the acquisition of resistance to current antimicrobials pose a serious challenge for therapy, and new measures to treat and prevent this infectious pathogen are of crucial importance. Plant essential oils (EOs) and their constituents are promising agents with antimicrobial properties. The aim of this study was to evaluate the antistaphylococcal effect of essential oils from Salvia officinalis using the broth-microdilution method. Essential oils of S. officinalis were isolated from the same individual, but at different life stages - young and old leaves. The effects of combinations of sub-inhibitory concentrations of oil and different antibiotics were evaluated by the checkerboard method. The results, expressed as the fractional inhibitory concentration (FIC) and index (FICI), indicate that the essential oil isolated from young leaves potentiated the inhibitory effect of antibiotics against tested MRSA strains.
The antibacterial activity of peppermint oil and different extracts of Mentha piperita against some Gram-positive and Gram-negative bacterial strains was evaluated in the present research work by agar well diffusion method. It was found that the distilled concentrations of essential oil inhibited the growth of microorganisms and the results were comparable with those of antibiotic gentamycin. Essential oils showed a wider spectrum of activity but less strong inhibition as compared to the investigated commercial antibiotic. Minimum inhibitory concentrations (MICs) for the bacterial species ranged from 0.4% to 0.7% v/v. The oil and extracts also exhibited significant antioxidant activity and the oil showed about half potency when compared to the standard BHT. These results indicated the strong antibacterial and antioxidant activities of peppermint oil but additional investigations need to be performed in order to confirm the safety of these concentrations (MIC) for human consumption. Peppermint oil could be used as a good conservation agent by inhibiting some food borne pathogens.
Tea tree oil has recently emerged as an effective topical antimicrobial agent active against a wide range of organisms. Tea tree oil may have a clinical application in both the hospital and community, especially for clearance of methicillin-resistant Staphylococcus aureus (MRSA) carriage or as a hand disinfectant to prevent cross-infection with Gram-positive and Gramnegative epidemic organisms. Our study, based on the time-kill approach, determined the kill rate of tea tree oil against several multidrug-resistant organisms, including MRSA, glycopeptide-resistant enterococci, aminoglycoside-resistant klebsiellae, Pseudomonas aeruginosa and Stenotrophomonas maltophilia, and also against sensitive microorganisms. The study was performed with two chemically different tea tree oils. One was a standard oil and the other was Clone 88 extracted from a specially bred tree, which has been selected and bred for increased activity and decreased skin irritation. Our results confirm that the cloned oil had increased antimicrobial activity when compared with the standard oil. Most results indicated that the susceptibility pattern and Gram reaction of the organism did not influence the kill rate. A rapid killing time (less than 60 min) was achieved with both tea tree oils with most isolates, but MRSA was killed more slowly than other organisms.
This study investigated the chemical composition and evaluated the antioxidant, antimicrobial, cytotoxic and anti-acetylcholinesterase properties of Tunisian Origanum majorana essential oil. The findings showed that the oil exhibited high activity, particularly in terms of reducing power and β-Carotene bleaching, inducing higher IC50 values than BHT. The oil showed an important antimicrobial activity against 25 bacterial and fungal strains. In fact, the IZ, MIC and MBC values recorded for the bacterial strains were in the range of 8±0 -18.33±0.57 mm, 0.097-3.125 and 0.39-6.25 mg/mL, respectively. The IZ, MIC and MFC values of the fungal strains varied between 11±0-28±0 mm, 0.058-0.468 mg/mL and 0.234-1.875 mg/mL, respectively. A low cytotoxic effect was observed against cancer (Hep-2 and HT29) and continuous cell lineage (Vero), with CC50 values ranging from 13.73 to 85.63 mg/mL. The oil was also evaluated for anti-acetylcholinesterase effects, which showed that it exhibited significant activity with IC50 values reaching 150.33±2.02 μg/mL.
The aim of this work was to investigate the antibacterial activity of six Lamiaceae essential oils, against pathogenic and food spoilage bacteria. The chemical profiles of essential oils were evaluated by the means of GC and GC–MS. The major constituents of the oils were 1,8-cineol (29.2%), camphor (17.2%), α-pinene (11.5%) in Rosmarinus officinalis, citronellal (20.5%), β- geraniol (17.0%), β-citronellol (11.5%) in Melissa officinalis, 1,8-cineol (27.4%), α-thujone (16.3%), β-thujone (11.2%), borneol (10.4%), camphor (7.98%) in Salvia officinalis, linalool (25.1%), linalyl acetate (22.5%) in Lavandula angustifolia, thymol (52.4%), p-cymene (17.9%) in Thymus vulgaris and Patcholene alcohol (22.7%), α-bulnesene (17.1%), α-guaine (13.8%) in Pogostemon cablin. On quantitative basis, the amounts of 1,8-cineol, citronellal, 1,8-cineol, linalool, thymol and patchouli alcohol, calculated using calibrated curve with pure standard compounds, in the respective essential oils were found to be 28.4, 19.0, 26.7, 23.3, 51.1 and 21.1 g/100 g of oil, respectively. The modified resazurin microtitre-plate assay was used to evaluate the antibacterial activity of the essential oils and their principal components. All the essential oils analyzed presented inhibitory effects on most of the strains tested. Thymus vulgaris essential oil showed the highest inhibition. It was concluded that modified resazurin assay could be effectively used for reliable assessment of antibacterial activity of the tested essential oils against several Gram positive and negative bacterial taxa. The present results also demonstrated that Lamiaceae essential oils exhibiting higher antibacterial activity were generally rich in oxygenated monoterpens.
Biological activities of three essential oils of the Lamiaceae family. Medicines (Basel)
- G Nieto
Nieto G. 2017. Biological activities of three essential oils of the Lamiaceae family. Medicines (Basel).
4:1-10. doi:10.3390/medicines4030063.