Phytoconstituents and Ergosterol Biosynthesis-Targeting Antimicrobial Activity of Nutmeg (Myristica fragans Houtt.) against Phytopathogens.

In recent years, nutmeg (Myristica fragans Houtt.) has attracted considerable attention in the field of phytochemistry due to its diverse array of bioactive compounds. However, the potential application of nutmeg as a biorational for crop protection has been insufficiently explored. This study investigated the constituents of a nutmeg hydroethanolic extract via gas chromatography-mass spectrometry and vibrational spectroscopy. The research explored the extract's activity against phytopathogenic fungi and oomycetes, elucidating its mechanism of action. The phytochemical profile revealed fatty acids (including tetradecanoic acid, 9-octadecenoic acid, n-hexadecanoic acid, dodecanoic acid, and octadecanoic acid), methoxyeugenol, and elemicin as the main constituents. Previously unreported phytochemicals included veratone, gelsevirine, and montanine. Significant radial growth inhibition of mycelia was observed against Botrytis cinerea, Colletotrichum acutatum, Diplodia corticola, Phytophthora cinnamomi, and especially against Fusarium culmorum. Mode of action investigation, involving Saccharomyces cerevisiae labeled positively with propidium iodide, and a mutant strain affected in ERG6, encoding sterol C-24 methyltransferase, suggested that the extract induces a necrotic type of death and targets ergosterol biosynthesis. The evidence presented underscores the potential of nutmeg as a source of new antimicrobial agents, showing particular promise against F. culmorum.

Facile fabrication of carboxymethylcellulose/ZnO/g-C3N4 containing nutmeg extract with photocatalytic performance for infected wound healing.

New topical antibacterial agents are required to inhibit and development of bacteria and also promoting the wound healing process. This study was evaluating the healing effect of Myristica fragrans extract coated with carboxymethyl cellulose, zinc oxide and graphite carbon nitride (CMC/ZnO/g-C3N4/MyR) by photocatalytic process on the healing process of full-thickness infectious excision wounds in mice. Nanosheets were prepared and physicochemical properties were evaluated. Safety, in vitro release, antibacterial activities under in vitro and in vivo condition, wound contraction, histopathological properties and the protein expressions of tumor necrosis factor-α (TNF-α), collagen 1A (COL1A) and CD31 were also evaluated. Physicochemical properties confirmed their successful synthesis. Nanosheets exhibited antibacterial activity under in vitro and in vivo conditions. The formulations containing CMC/ZnO/g-C3N4/MyR, significantly (P < 0.05) competed with standard ointment of mupirocin for accelerating the wound healing process due to their effects on bacterial count and the expression of TNF-α and also accelerating the proliferative phase. This structure can be used as a safe structure in combination with other agents for accelerating the wound healing process following future clinical studies.

Inhibitory and antioxidative capacity of nutmeg extracts on reduction of lipid oxidation and heterocyclic amines in pan-roasted beef patties.

Identification and inhibition of mutagenic and carcinogenic heterocyclic amines (HCAs) from pan-roasted beef patties were performed by adding (0.02%) tertiary butyl hydroquinone (TBHQ) and (0.05%) ethanol-extracted nutmeg (ENE) using HPLC and principal component analysis. Ten HCAs, including six polar and four non-polar, were assessed. The addition of (0.05%) ENE significantly (P < 0.05) reduced the cooking loss and shrinkage of patties during cooking and reduced the total formation HCAs by 73.97%, which proved the significant (P < 0.05) inhibitory effect as a natural antioxidant against lipid oxidation and HCA formation compared to TBHQ. The DPPH radical-scavenging activity, total phenolic content, and available active metabolites of ENE were estimated. Furthermore, a positive correlation was observed between pH, level of thiobarbituric acid reactive substances, and HCA formation in both the groups. TBHQ and ENE were significant HCAs inhibitors (P < 0.001), but ENE showed resilient oxidative stability during refrigeration storage. Therefore, ENE can be used to reduce HCAs formation in pan-roasted beef patties.

Chemical composition, antibacterial efficacy, and antioxidant capacity of essential oil and oleoresin from Monodora myristica and Tetrapleura tetraptera in Southeast Nigeria.

Specific to the West African sub-region, previous studies involving fruit, stem, and bark of Tetrapleura tetraptera as well as seeds of Monodora myristica have largely focused on phytochemical properties of aqueous and methanolic and ethanolic extracts. To supplement existing information, the chemical composition, antibacterial efficacy (tested against Escherichia coli and Staphylococcus aureus), and antioxidant capacity (1,1-diphenyl-2-picrylhydrazyl (DPPH∙) radical scavenging, ferric reducing power, and total antioxidant capacity) of essential oil and oleoresin extracted from T. tetraptera fruit and M. myristica seeds cultivated in Southeast Nigeria, were studied. Essential oil and oleoresin were respectively extracted by steam distillation and aqueous maceration. By way of gas chromatograph mass spectrometry (GC-MS) analysis, the chemical compounds from essential oil and oleoresin from M. myristica and T. Tetraptera samples totaled 6 and 5, as well as 27 and 16, respectively. Besides the oleoresin of M. myristica and the essential oil of T. tetraptera showing some resistance against S. aureus, the oleoresins seemed highly susceptible to E. coli-all of which demonstrated concentration-dependence to the antibacterial inhibition zone. Scavenging DPPH radical, reduction power activity, and total antioxidant capacity increased with essential oil and oleoresin extracts' concentrations, which positions M. myristica and T. tetraptera spices as very promising for food preservation, especially against autoxidation and microbial spoilage.

Effect of Grinding Process Parameters and Storage Time on Extraction of Antioxidants from Ginger and Nutmeg.

The aim of this study was to optimize the grinding process parameters (mesh size of grinder sieve (X1), the peripheral velocity of the grinding wheels (X2)), and the storage time (X3) of ground ginger rhizome and nutmeg to obtain ethanol and ethanol-water extracts with improved antioxidant properties. The optimal conditions were estimated using response surface methodology (RSM) based on a three-variable Box-Behnken design (BBD) in order to maximize the antioxidant capacity (AC) determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods, and the total phenolic content (TPC) was determined by the Folin-Ciocalteu (F-C) method in spice extracts. Additionally, the phenolic acid profiles in extracts from optimized conditions were analyzed using ultra-performance liquid chromatography (UPLC). It was found that the optimal preparation conditions for antioxidant extraction were dependent on the spice source and solvent type. The best antioxidant properties in nutmeg extracts were achieved for X1 = 1.0 mm, X2 = 40-41 Hz and X3 = 7 days, whereas the optimized parameters for ginger extracts were more varied (1.0-2.0 mm, 43-50 Hz and 1-9 days, respectively). The ginger extracts contained 1.5-1.8 times more phenolic acids, and vanillic, ferulic, gallic, and p-OH-benzoic acids were dominant. In contrast, the nutmeg extracts were rich in protocatechuic, vanillic, and ferulic acids.

Hepatoprotective effect of nanoniosome loaded Myristica fragrans phenolic compounds in mice-induced hepatotoxicity.

In this study, nanoniosome-loaded Myristica fragrans' (MF) phenolic compounds (NLMP) were synthesized and characterized for their physical properties, and hepatoprotective effects on mice with liver toxicity induced by L-asparaginase (LA) injection. According to the results, NLMP has a spherical shape with a 263 nm diameter, a zeta potential of -26.55 mV and a polydispersity index (PDI) of 0.192. The weight and feed intake of mice induced with hepatotoxicity were significantly (p ≤ 0.05) increased after they were treated with NLMP (2.5 mg/kg body weight of mice). In addition, the blood levels of triglyceride (TG), cholesterol (Chol), liver enzymes (aspartate aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP)) and total bilirubin were significantly (p ≤ 0.05) decreased. A significant increase (p ≤ 0.05) in the blood levels of the antioxidant defence system (glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT)) were also reported after NLMP treatment. NLMP was also led to a significant decrease (p ≤ 0.05) in inflammatory-related gene expression of inducible nitric oxide synthase (iNOS) and Interferon-gamma (IFN-γ) in the liver, as well as a meaningful (p ≤ 0.05) increase in the expression of SOD as an antioxidant status biomarker. Consequently, the NLMP is recommended as a potential dietary supplement to alleviate the symptoms of LA-induced hepatotoxicity.

Anti-Proliferative Acyl Phenols and Arylnonanoids from the Fruit Rind of Myristica malabarica Lam.

Phytochemical investigation of the methanol extract of the fruit rind of Myristica malabarica led to the isolation of eight known compounds that were identified as malabaricones A-D, promalabaricones B and C, 1-(2,6-dihydroxyphenyl)tetradecan-1-one, and ericanone by comparison with literature spectroscopic data. The structures of malabaricones A-D, promalabaricone B, and 1-(2,6-dihydroxyphenyl)tetradecan-1-one were confirmed by X-ray crystallography. In vitro assay of the isolated phenols indicated that they exhibited moderate anti-proliferative activity against the A2780 human ovarian cancer cell. Compounds (1, 3, 5, 6 and 7) had the most potent activities, whereas the anti-proliferative activities of compounds 2 and 4 were less potent.

The application of proteomics and metabolomics to reveal the molecular mechanism of Nutmeg-5 in ameliorating cardiac fibrosis following myocardial infarction.

BACKGROUND: Nutmeg-5, an ancient and classic formula in traditional Mongolian medicine comprising five kinds of traditional Chinese medicine, is widely used in the treatment of myocardial infarction (MI, called heart "Heyi" disease in Mongolian medicine). Cardiac fibrosis plays a critical role in the development and progression of heart failure after MI. However, the material basis and pharmacological mechanisms of the effect of Nutmeg-5 on cardiac fibrosis after MI remain unclear. OBJECTIVE: The aim of this study was to first explore the potential material basis and molecular mechanism of action of Nutmeg-5 in improving cardiac fibrosis after MI via a multiomics approach. METHODS: The constituents in Nutmeg-5 were identified by ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). High-performance liquid chromatography (HPLC) and gas chromatography (GC)-based fingerprints of Nutmeg-5 were analysed, and characteristic peaks were identified by comparison to standard samples. A rat MI model was created by permanent ligation of the left anterior descending artery. The protective effect of Nutmeg-5 on cardiac fibrosis after MI was evaluated by tissue histology and measurement of the serum biomarkers of myocardial injury. Cardiac fibrosis levels were evaluated by Sirius red staining. Differentially expressed proteins in the myocardium and metabolites in the serum were explored by proteomic and untargeted metabolome analyses, respectively. Pearson correlation analysis was performed to explore the association between serum metabolites and myocardial proteins. RESULTS: A total of 67 constituents were identified in Nutmeg-5 by UPLC-MS/MS. Sixteen components were identified in the fingerprint of Nutmeg-5 by comparison with a standard sample. Six lactones were isolated from Nutmeg-5 and quantified by HPLC and GC. MI was significantly alleviated in Nutmeg-5-treated rats compared to MI rats, as demonstrated by their decreased mortality, improved cardiac function, and attenuated cardiac fibrosis and myocardial injury. A total of 252 significant differential metabolites were identified in plasma between model and Nutmeg-5-treated rats by untargeted metabolome analysis. Among these, 36 critical metabolites were associated with Nutmeg-5 activity. Proteomic analysis identified 338 differentially expressed proteins in the rat myocardium between MI and Nutmeg-5-treated rats, including 204 upregulated and 134 downregulated proteins. Protein set enrichment analysis revealed that Nutmeg-5 treatment significantly inhibited the extracellular matrix (ECM)-receptor interaction pathway, which was activated in the myocardium of MI rats. A significant decrease in collagen and alpha smooth muscle actin expression levels was found in the myocardium of Nutmeg-5-treated rats compared to MI rats. These results illustrated that Nutmeg-5 had a significant protective effect on cardiac fibrosis after MI. A significant correlation was found between the ECM-receptor interaction pathway in the myocardium and critical metabolites in the serum. In addition, there were positive correlations between the levels of critical metabolites and the expression levels of transforming growth factor (TGF)-ß1 and Smad2 in the rat myocardium. CONCLUSIONS: Nutmeg-5 alleviated cardiac fibrosis after MI in rats by inhibiting the myocardial ECM-receptor interaction pathway and TGF-ß1/Smad2 signalling, which was achieved by regulating plasma metabolites.

Excito-repellency of Myristica fragrans Houtt. and Curcuma longa L. extracts from Southern Thailand against Aedes aegypti (L.).

The development of local plant extracts as a mosquito repellent is environmentally safe, inexpensive, and easily accessible for residents. In this study, three extracts from two local plants, Myristica fragrans Houtt. (flesh and mace) and Curcuma longa L. (rhizome) from southern Thailand, were investigated for their inherent repellent activity using the excito-repellency (ER) assay system against insectary-colonized Aedes aegypti (L.) (Diptera: Culicidae). The escape responses of mosquitoes exposed to concentrations of 0.5% to 5.0% (w/v) were measured to determine the contact irritant and non-contact repellent properties of each extract. Both the flesh and mace extracts of M. fragrans had relatively limited contact irritants (28.1% and 34.6% escape) and non-contact repellent (16.7% and 18.3% escape) activities against Ae. aegypti, respectively. The C. longa rhizome extract produced higher escape responses in the non-contact (42.6% escape) and contact (41.4% escape) trials at concentrations of 5.0% and 1.0%, respectively. GC-MS analysis found diethyl malate (56.5%) and elemicin (11.7%) to be the main components of the flesh and mace extracts, respectively, while ar-turmerone (24.6%), ß-turmerone (15.2%), α-turmerone (10.5%) were the primary constituents of the rhizome extract. Overall, our results indicate that both M. fragrans extracts primarily caused Ae. aegypti escape through contact irritation. For C. longa, lower concentrations (0.5% and 1.0%) exhibited contact irritancy, but higher concentrations (2.5% and 5.0%) exhibited non-contact repellency against Ae. aegypti. Although they had limited efficacy, further experiments (e.g., mixing with other plant-based compounds) could enhance the ER of both local plant extracts. Additional evaluation of these extracts against other mosquito species and the ER of their chemical components, either alone or in combination, would also be beneficial for the development of green repellents. Our findings emphasize the possibility of utilizing plant-based mosquito repellent as an alternative personal protection method for future mosquito control programs.

Nutmeg (Myristica fragrans Houtt.) essential oil: A review on its composition, biological, and pharmacological activities.

Myristica fragrans (Houtt.) is an evergreen tree native to the Maluku Islands, Indonesia. M. fragrans kernel is extensively used in Indian traditional medicines to treat various diseases. Several studies attempt to compile and interpret the pharmacological potential of Myristica fragrans (Houtt.) aqueous and various chemical extracts. Thus, the pharmacological potential of nutmeg essential oil has not been reviewed phytochemically and pharmacologically. Therefore, the present study aimed to share appropriate literature evidence regarding the plant essential oil chemical composition and therapeutic potential of Myristica fragrans essential oil (MFEO). MFEO of leaf, mace, kernel, and seed were used worldwide as potential Ayurvedic medicine and fragrance. MFEO extracted by various methods and oil yield was 0.7-3.2, 8.1-10.3, 0.3-12.5, and 6.2-7.6% in leaf, mace, seed, and kernel. The primary chemical constituents of MFEO were sabinene, eugenol, myristicin, caryophyllene, ß-myrcene, and α-pinene. Clinical and experimental investigations have confirmed the antioxidant, antimicrobial, antiinflammatory, anticancer, antimalarial, anticonvulsant, hepatoprotective, antiparasitic, insecticidal, and nematocidal activities of MFEO. It is the first attempt to compile oil yield, composition, and the biological activities of MFEO. In future, several scientific investigations are required to understand the mechanism of action of MFEO and their bioactive constituents.

Myristica fragrans Extract Regulates Gut Microbes and Metabolites to Attenuate Hepatic Inflammation and Lipid Metabolism Disorders via the AhR-FAS and NF-κB Signaling Pathways in Mice with Non-Alcoholic Fatty Liver Disease.

Recent studies have shown that non-alcoholic fatty liver disease (NAFLD) is closely related to the gut microbiome. Myristica fragrans is widely used as a traditional seasoning and has a therapeutic effect on gastrointestinal diseases. Although previous studies have shown that M. fragrans extracts have anti-obesity and anti-diabetes effects in mice fed a high-fat diet, few studies have determined the active components or the corresponding mechanism in vivo. In this study, for the first time, an M. fragrans extract (MFE) was shown to be a prebiotic that regulates gut microbes and metabolites in mice fed a high-fat diet. Bioinformatics, network pharmacology, microbiome, and metabolomics analyses were used to analyze the nutrient-target pathway interactions in mice with NAFLD. The National Center for Biotechnology Information Gene Expression Omnibus database was used to analyze NAFLD-related clinical data sets to predict potential targets. The drug database and disease database were then integrated to perform microbiome and metabolomics analyses to predict the target pathways. The concentrations of inflammatory factors in the serum and liver, such as interleukin-6 and tumor necrosis factor-α, were downregulated by MFE. We also found that the hepatic concentrations of low-density lipoprotein cholesterol, total cholesterol, and triglycerides were decreased after MFE treatment. Inhibition of the nuclear factor kappa B (NF-κB) pathway and downregulation of the fatty acid synthase (FAS)-sterol regulatory element-binding protein 1c pathway resulted in the regulation of inflammation and lipid metabolism by activating tryptophan metabolite-mediated aryl hydrocarbon receptors (AhR). In summary, MFE effectively attenuated inflammation and lipid metabolism disorders in mice with NAFLD through the NF-κB and AhR-FAS pathways.

Phenylpropanoids and neolignans isolated from Myristica fragrans enhance glucose uptake in myotubes.

Nutmeg is the seed of Myristica fragrans or its powder and is used as a spice and a traditional medicine. The antidiabetic effect of nutmeg is not fully understood yet. In this study, we examine the isolation and identification of the active compounds of Myristica fragrans with regards to glucose uptake and elucidate their mechanism in L6 myotubes. Myrisiticin, licarin B, erythro-2-(4-allyl-2,6-dimethoxy-phenoxy)-1-(3,4-dimethoxyphenyl)-propan-1-ol (ADDP) and (7S,8R)-2-(4-allyl-2,6-dimethoxyphenoxy)-1-(3,4,5-trimethoxyphenyl)-propan-1-ol (ADTP) were isolated and identified as the active compounds. Myristicin or a mixture of ADDP and ADTP promoted the translocation of glucose transporter 4 (GLUT4) through phosphorylation of AMP-activated protein kinase in L6 myotubes 15 min after treatment, while licarin B promoted it 240 min after treatment. Oral administration of the fraction from Myristica fragrans containing these active compounds to ICR mice suppressed post-prandial hyperglycemia. Thus, Myristica fragrans is a promising functional food to prevent post-prandial hyperglycemia and type 2 diabetes mellitus by promoting glucose uptake in muscle.

Mechanisms and Safety of Antidepressant-Like Effect of Nutmeg in Mice.

Nutmeg, a dried seed kernel of a tall evergreen Myristicaceae tree, is widely used as a spice and herbal medicine and is known to have antidepressant-like effects. This study evaluates the mechanisms underlying this antidepressant-like effect and safety of nutmeg n-hexane extract (NNE) in mice. Tail suspension and open field tests showed that NNE (10 mg/kg, per OS (p.o.)) significantly decreased the immobility time of mice without effecting their spontaneous locomotor activity. The reduction of immobility time of mice elicited by NNE was significantly inhibited by ketanserin (5-hydroxytryptamine (5-HT)2A/2C receptor antagonist), ondansetron (5-HT3 receptor antagonist), and yohimbine (α2 receptor antagonist). WAY100635 (5-HT1A receptor antagonist) tended to inhibit the effect of NNE but without significance. Testing according to the Organisation for Economic Co-operation and Development Guidelines, no mice died due to administrated NNE (2000 mg/kg, p.o.), and behavioral and weight changes were not seen in the acute toxicity test. In the Ames test, no increase in the number of revertant colonies for each bacterial strain test strains TA98 and TA100 by nutmeg powder was observed either with or without metabolic activity by S9 mix. These results suggest that NNE shows an antidepressant-like effect involving various serotonergic and noradrenergic nervous systems and maybe a highly safe natural preparation.

Neolignans from Myristica fragrans seeds, revision of their absolute configurations, reduction products and biological activities.

Chromatographic purification of the CH2Cl2 extract of Myristica fragrans seeds provided 19 known compounds, four dihydrofuran neolignans, licarines A, B and maceneolignans A, B were among the isolates. Prior to hydrogenation, in order to obtain their di- and tetrahydrogenated products, the absolute configuration of these compounds was thoroughly investigated based on their optical rotations and ECD spectra. This report provides evidences concerning the disagreement between the use of an aromatic quadrant rule and time-dependent density function theory calculation for the prediction of the absolute configurations at C-7 and C-8 in these dihydrobenzofuran neolignans. The absolute configurations of licarines A, B and maceneolignans A, B were subsequently redefined. The antimicrobial and cytotoxic activities of the isolates and reduction products of licarines A, B and maceneolignans A, B were also investigated.

Phytochemical investigation and anticholinesterase activity of ethyl acetate fraction of Myristica fragrans Houtt. seeds.

In this work, n-hexane, chloroform, and ethyl acetate fractions of the methanol extract of Myristica fragrans Houtt. seeds were evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) via Ellman's method. It was found that all fractions depicted no anti-AChE activity, however, they were active toward BChE with IC50 values of 361.8, 215.0, and 145.8 µg/mL, respectively comparing with donepezil as the reference drug (IC50 = 1.97 µg/mL). The ethyl acetate fraction which also showed high neuroprotectivity and metal chelating ability was selected for the phytochemical analysis. Our results confirmed the presence of trimyristin and 5,7-diacetyl chrysin (reported for the first time in M. fragrans) in the corresponding fraction.

Antifungal, Antibacterial, and Cytotoxic Activities of Silver Nanoparticles Synthesized from Aqueous Extracts of Mace-Arils of Myristica fragrans.

In the present study, mace-mediated silver nanoparticles (mace-AgNPs) were synthesized, characterized, and evaluated against an array of pathogenic microorganisms. Mace, the arils of Myristica fragrans, are a rich source of several bioactive compounds, including polyphenols and aromatic compounds. During nano synthesis, the bioactive compounds in mace aqueous extracts serve as excellent bio reductants, stabilizers, and capping agents. The UV-VIS spectroscopy of the synthesized NPs showed an intense and broad SPR absorption peak at 456 nm. Dynamic light scattering (DLS) analysis showed the size with a Z average of 50 nm, while transmission electron microscopy (TEM) studies depicted the round shape and small size of the NPs, which ranged between 5-28 nm. The peaks related to important functional groups, such as phenols, alcohols, carbonyl groups, amides, alkanes and alkenes, were obtained on a Fourier-transform infrared spectroscopy (FTIR) spectrum. The peak at 3 keV on the energy dispersive X-ray spectrum (EDX) validated the presence of silver (Ag). Mace-silver nanoparticles exhibited potent antifungal and antibacterial activity against several pathogenic microorganisms. Additionally, the synthesized mace-AgNPs displayed an excellent cytotoxic effect against the human cervical cancer cell line. The mace-AgNPs demonstrated robust antibacterial, antifungal, and cytotoxic activity, indicating that the mace-AgNPs might be used in the agrochemical industry, pharmaceutical industry, and biomedical applications. However, future studies to understand its mode of action are needed.

Pharmacological and Therapeutic Potential of Myristicin: A Literature Review.

Natural products have been used by humanity for many centuries to treat various illnesses and with the advancement of technology, it became possible to isolate the substances responsible for the beneficial effects of these products, as well as to understand their mechanisms. In this context, myristicin, a substance of natural origin, has shown several promising activities in a large number of in vitro and in vivo studies carried out. This molecule is found in plants such as nutmeg, parsley, carrots, peppers, and several species endemic to the Asian continent. The purpose of this review article is to discuss data published in the last 10 years at Pubmed, Lilacs and Scielo databases, reporting beneficial effects, toxicity and promising data of myristicin for its future use in medicine. From 94 articles found in the literature, 68 were included. Exclusion criteria took into account articles whose tested extracts did not have myristicin as one of the major compounds.

Comparison of antifungal activity of selected essential oils against Fusarium graminearum in vitro.

INTRODUCTION: Fusaria are microscopic filamentous fungi which are spread in soil, in various organic substrates, and include more than 80 phytopathogenic species which are predominantly hosted by cereals, fruits and vegetables. Many of these species, under certain conditions, are capable of synthesizing secondary metabolites, mycotoxins. At present, various substances are used for their elimination and one of the solutions appears to be essential oils. In the presented study, the antifungal activity of essential oils was researched in vitro. MATERIAL AND METHODS: In this study, two standard fungal isolates Fusarium graminearum CCM F-683 and Fusarium graminearum CCM 8244 (Brno, Czech Republic) were used. The antifungal effect of 6 tested essential oils (Syzygium aromaticum, Origanum vulgare, Thymus vulgaris, Hyssopus officinalis , Ocimum basilicum, Myristica fragrans) was determined using the broth microdilution method, which allows reading of the MIC (minimum inhibitory concentration). According to the results obtained, the growth inhibition of Fusarium graminearum was determined by assay for the inhibition of radial growth of the mycelium. RESULTS: The inhibitory effects of thymus, oregano, basil, myristica, hyssop and syzygium essential oil (EO) on mycelial growth of Fusarium graminearum CCM F-683 and CCM 8244 were investigated. The best antifungal activity against the both strains of Fusarium graminearum (37.4%; 40.7%) was demonstrated by Origanum vulgare EO at the concentration 100 µg/mL. Among the four tested oils, three (Syzygium aromaticum, Thymus vulgaris, Origanum vulgare) achieved the best inhibitory effect (100%) at concentrations 500 µg/mL and 1000 µg/mL. CONCLUSIONS: In the protection of plants against pathogenic fungi, essential oils appear to be a suitable substitute for synthetic chemicals.

Inhibition of Bacterial Efflux Pumps by Crude Extracts and Essential Oil from Myristica fragrans Houtt. (Nutmeg) Seeds against Methicillin-Resistant Staphylococcus aureus.

Myristicafragrans Houtt. (Nutmeg) is a widely known folk medicine across several parts of Asia, particularly used in antimicrobial treatment. Bacterial resistance involves the expression of efflux pump systems (chromosomal norA and mepA) in methicillin-resistant Staphylococcus aureus (MRSA). Crude extract (CE) and essential oil (EO) obtained from nutmeg were applied as efflux pump inhibitors (EPIs), thereby enhancing the antimicrobial activity of the drugs they were used in. The major substances in CE and EO, which function as EPIs, in a descending order of % peak area include elemicin, myristicin, methoxyeugenol, myristicin, and asarone. Here, we investigated whether the low amount of CE and EO used as EPIs was sufficient to sensitize MRSA killing using the antibiotic ciprofloxacin, which acts as an efflux system. Interestingly, synergy between ciprofloxacin and CE or EO revealed the most significant viability of MRSA, depending on norA and mepA, the latter being responsible for EPI function of EO. Therefore, CE and EO obtained from nutmeg can act as EPIs in combination with substances that act as efflux systems, thereby ensuring that the MRSA strain is susceptible to antibiotic treatment.