Zein-Based Films Containing Monolaurin/Eugenol or Essential Oils with Potential for Bioactive Packaging Application

Zein is renewable plant protein with valuable film-forming properties that can be used as a packaging material. It is known that the addition of natural cross-linkers can enhance a film’s tensile properties. In this study, we aimed to prepare antimicrobial zein-based films enriched with monolaurin, eugenol, oregano, and thyme essential oil. Films were prepared using the solvent casting technique from ethanol solution. Their physicochemical properties were investigated using structural, morphological, and thermal techniques. Polar and dispersive components were analyzed using two models to evaluate the effects on the surface free energy values. The antimicrobial activity was proven using a disk diffusion method and the suppression of bacterial growth was confirmed via a growth kinetics study with the Gompertz function. The films’ morphological characteristics led to systems with uniform distribution of essential oils or eugenol droplets combined with a flat-plated structure of monolaurin. A unique combination of polyphenolic eugenol and amphiphilic monoglyceride provided highly stretchable films with enhanced barrier properties and efficiency against Gram-positive and Gram-negative bacteria, yeasts, and molds. The prepared zein-based films with tunable surface properties represent an alternative to non-renewable resources with a potential application as active packaging materials.

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Evaluation of the in vitro antibacterial activity of some essential oils and their blends against Staphylococcus spp. isolated from episodes of sheep mastitis

RENDICONTI LINCEI ◽

10.1007/s12210-021-00991-5 ◽

2021 ◽

Author(s):

Filippo Fratini ◽

Margherita Giusti ◽

Simone Mancini ◽

Francesca Pisseri ◽

Basma Najar ◽

...

Keyword(s):

Antibacterial Activity ◽

Essential Oils ◽

Diffusion Method ◽

Minimal Bactericidal Concentration ◽

Coagulase Negative Staphylococci ◽

Disk Diffusion Method ◽

In Vitro Antibacterial Activity ◽

High Concentrations ◽

Thymus Serpyllum

AbstractStaphylococcus aureus and coagulase-negative staphylococci are among the major causes of mastitis in sheep. The main goal of this research was to determine the in vitro antibacterial activity of several essential oils (EOs, n 30), then five of them were chosen and tested alone and in blends against staphylococci isolates. Five bacteria were isolated from episodes of ovine mastitis (two S. aureus and three S. xylosus). Biochemical and molecular methods were employed to identify the isolates and disk diffusion method was performed to determine their antimicrobial-resistance profile. The relative percentage of the main constituents in the tested essential oils and their blends was detected by GC-EIMS analysis. Antibacterial and bactericidal effectiveness of essential oils and blends were evaluated through minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). All of them showed sensitivity to the used antimicrobials. The EOs with the highest antibacterial activity were those belonging to the Lamiaceae family characterized by high concentrations of thymol, carvacrol and its precursor p-cymene, together with cinnamon EO, rich in cinnamaldehyde. In terms of both MIC and MBC values, the blend composed by Thymus capitatus EO 40%, Cinnamomum zeylanicum EO 20%, Thymus serpyllum EO 20% and Satureja montana EO 20% was found to be the most effective against all the isolates. Some essential oils appear to represent, at least in vitro, a valid tool against ovine mastitis pathogens. Some blends showed a remarkable effectiveness than the single oils, highlighting a synergistic effect in relation to the phytocomplex.

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USING ESSENTIAL OILS TO COMBAT THE THREAT OF MULTI-DRUG RESISTANT BACTERIA, PSEUDOMONAS AERUGINOSA

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2016v8i12.13564 ◽

2016 ◽

Vol 8 (12) ◽

pp. 180 ◽

Cited By ~ 1

Author(s):

Jenies Grullon ◽

James P. Mack ◽

Albert Rojtman

Keyword(s):

Pseudomonas Aeruginosa ◽

Essential Oils ◽

Alternative Treatment ◽

Scientific Discovery ◽

Diffusion Method ◽

Resistant Bacteria ◽

Human Beings ◽

Disk Diffusion Method ◽

Cinnamon Bark

<div class="WordSection1">Objective: The development of antibiotics was a revolutionary scientific discovery and medical advancement that greatly extended the life expectancy of mankind. Through less than 100 y of using antibiotics to treat infectious bacteria, some of these highly adaptive organisms have developed resistance to the drugs. The healthcare field is greatly concerned with the threat of many common infections that have been considered treatable for decades, regaining its ability to be severely fatal; thus, making alternative treatments currently in high demand. This study concentrated on investigating an alternative treatment for a specific gram-negative bacterium, Pseudomonas aeruginosa (P. aeruginosa), a resistance-gaining bacteria that commonly infects hospitalized patients with weakened immune systems and/or open wounds.Methods: Prior to the age of modern medicine, human beings relied on nature for medicinal treatments. In our research, we focused on determining the in vitro efficacy of using the essential oils, cassia and cinnamon bark, their major component, cinnamaldehyde, as well as the major component of manuka honey, methylglyoxal, as an alternative treatment against P. aeruginosa We tested cassia, cinnamon bark, cinnamaldehyde, and methylglyoxal using the Kirby-Bauer disk diffusion method; the diameter of the zone of inhibition for each treated bacterial sample was measured and compared with the standard antibiotic treatments, tobramycin, and amikacin.Results: This study showed that the selected essential oils, cinnamaldehyde, and methylglyoxal were as effective or better in inhibiting the growth of P. aeruginosa compared to the standard aminoglycoside antibiotics.Conclusion: The tested essential oils, cinnamaldehyde, and methylglyoxal may be useful as an alternative treatment for infections caused by P. aeruginosa and may also provide communities where antibiotics are not readily available, a cost-effective way to treat this infectious disease.</div>

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In Vitro Efficacy of Essential Oils from Melaleuca Alternifolia and Rosmarinus Officinalis, Manuka Honey-based Gel, and Propolis as Antibacterial Agents Against Canine Staphylococcus Pseudintermedius Strains

Antibiotics ◽

10.3390/antibiotics9060344 ◽

2020 ◽

Vol 9 (6) ◽

pp. 344

Author(s):

Gabriele Meroni ◽

Elena Cardin ◽

Charlotte Rendina ◽

Valentina Rafaela Herrera Millar ◽

Joel Fernando Soares Filipe ◽

...

Keyword(s):

Essential Oils ◽

Antimicrobial Agents ◽

Antibacterial Properties ◽

Rosmarinus Officinalis ◽

Diffusion Method ◽

Melaleuca Alternifolia ◽

Disk Diffusion Method ◽

Staphylococcus Pseudintermedius ◽

Tea Tree

Essential oils (EOs) and honeybee products (e.g., honey and propolis) are natural mixtures of different volatile compounds that are frequently used in traditional medicine and for pathogen eradication. The aim of this study was to evaluate the antibacterial properties of tea tree (Melaleuca alternifolia) EO (TTEO), Rosmarinus officinalis EO (ROEO), manuka-based gel, and propolis against 23 strains of Staphylococcus pseudintermedius (SP) isolated from canine pyoderma. Antimicrobial resistance screening was assessed using a panel of nine antimicrobial agents coupled with a PCR approach. An aromatogram was done for both EOs, using the disk diffusion method. The minimum inhibitory concentration (MIC) was determined for all the compounds. Among the 23 SP strains, 14 (60.9%) were multidrug-resistant (MDR), 11 strains (47.8%) were methicillin-resistant (MRSP), and 9 (39.1%) were non-MDR. The mean diameter of the inhibition zone for Melaleuca and Rosmarinus were 24.5 ± 8.8 mm and 15.2 ± 8.9 mm, respectively, resulting as statistically different (p = 0.0006). MIC values of TTEO and ROEO were similar (7.6 ± 3.2% and 8.9 ± 2.1%, respectively) and no statistical significances were found. Honeybee products showed lower MIC compared to those of EOs, 0.22 ± 0.1% for Manuka and 0.8 ± 0.5% for propolis. These findings reveal a significant antibacterial effect for all the tested products.

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The influence of plant essential oils on in vitro growth of Pectobacterium and Dickeya spp. bacteria

Acta Scientiarum Polonorum Hortorum Cultus ◽

10.24326/asphc.2021.6.3 ◽

2021 ◽

Vol 20 (6) ◽

pp. 19-29

Author(s):

Małgorzata Schollenberger ◽

Agnieszka Gadomska-Gajadhur ◽

Ewa Mirzwa-Mróz ◽

Damian Kret ◽

Ewa Skutnik ◽

...

Keyword(s):

Essential Oils ◽

Soft Rot ◽

Inhibitory Effect ◽

Diffusion Method ◽

Juniperus Virginiana ◽

Bacterial Strains ◽

Disk Diffusion Method ◽

First Report ◽

Plant Essential Oils

The activity of essential oils from Eucalyptus globulus, Pinus silvestris, Lavandula angustifolia, Juniperus virginiana, Rosmarinus officinalis and Citrus paradise against the soft-rot pathogens Pectobacterium carotovorum subsp. carotovorum, Pectobacterium atrosepticum, Pectobacterium parmentieri and Dickeya solani was determined in vitro. The antibacterial activity of the essential oils will be evaluated using the disk-diffusion method by Kirby-Bauer [Bauer et al. 1966]. It was found that all the presented essential oils varied in antimicrobial activity against the four bacterial strains. No differences in the influence of streptomycin on inhibition of growth of the four bacterial strains were observed. Among six tested plants, essential oils from P. sylvestris had the strongest inhibitory effect on the growth of soft rot bacteria from Pectobacterium genus. This paper constitute the first report on the activity of the essential oils obtained from J. virginiana against soft rot bacteria. They are also the first report on the activity of the essential oils obtained from E. globulus, P. silvestris, L. angustifolia and C. paradisi against P. atrosepticum, P. parmentieri and D. solani as well as on the activity of the R. officinalis essential oils against P. atrosepticum and P. parmentieri.

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Antifungal activity of some vegetal extracts on Candida biofilms developed on inert substratum

Biointerface Research in Applied Chemistry ◽

10.33263/briac11.015023 ◽

2011 ◽

Vol 1 (1) ◽

pp. 015-023 ◽

Cited By ~ 10

Keyword(s):

Essential Oils ◽

Virulence Factors ◽

Antifungal Drugs ◽

Test Method ◽

Diffusion Method ◽

Time Curve ◽

Disk Diffusion Method ◽

Variable Intensity ◽

Plant Materials ◽

Coordinated Expression

Essential oils extracted from Citrus maxima (epicarp), Anethum graveolens (fruits) and Picea abies (leaves) were investigated for their ability to inhibit the growth and coordinated expression of virulence factors in Candida sp. strains recently isolated from clinical specimens, identified by using Vitek II automatic system and tested for susceptibility to antifungal drugs by E-test method. Plant materials were hydrodistiled in a Neo Clevenger type apparatus. Qualitative screening was performed using killing time curve and an adapted disk diffusion method. The microtiter method was used for establishing the influence of the essential oils on the microbial adherence to inert substrata. Subinhibitory concentrations of the tested essential oils were studied for their interference with the expression of soluble enzymatic virulence factors. All extracts exhibited an inhibitory activity of variable intensity on the microbial growth of planktonic as well as adherent strains, demonstrating the potential effect of the active compounds on the coordinated expression of virulence factors and consequently, on the initiation and progression of a fungal biofilm associated infection.

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Chemical composition and antimicrobial activity of Myrtus communis essential oils from Algeria

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d220249 ◽

2021 ◽

Vol 22 (2) ◽

Author(s):

YACINE MOHAMADI ◽

TAKIA LOGRADA ◽

Messaoud Ramdani ◽

GILLES FIGUEREDO ◽

PIERRE CHALARD

Keyword(s):

Antimicrobial Activity ◽

Chemical Composition ◽

Essential Oils ◽

Bacterial Species ◽

Antibacterial Activities ◽

Geranyl Acetate ◽

Diffusion Method ◽

Klebsiella Pneumonia ◽

Myrtus Communis ◽

Disk Diffusion Method

Abstract. Mohamadi Y, Lograda T, Ramdani M, Figueredo G, Chalard P. 2021. Chemical composition and antimicrobial activity of Myrtus communis essential oils from Algeria. Biodiversitas 22: 933-946. The objectives of this study were to determine the chemical composition and the antibacterial activities of Myrtus communis essential oils. The aerial parts of the myrtle were collected from nineteen localities of the Algerian coast, and subjected to hydrodistillation. The chemical composition of essential oils was analyzed using gas chromatography coupled with mass spectrometry (GC/MS). The antibacterial activity was evaluated by the disk diffusion method against ten bacterial species. Essential oils of M. communis was pale yellow oils, very fragrant, with an average yield of 0.68 ± 0.6%. Forty-six compounds were identified, representing an average of 99.17 ± 0.6% of total oils. The α-pinene was the most abundant component in the essential oils of all populations studied, with a mean of 50.1 ± 10.3%, followed by 1,8-cineole (22.27 ± 4.32%), limonene (5.16 ± 2.67%), linalool (3.79 ± 2.97%), α-terpineol (2.75 ± 1.12%), geranyl acetate (1.95 ± 0.7%) and methyl eugenol (1.40 ± 0.98%). Myrtenyl acetate was only observed in four populations with significant levels (from 10.66 to 20.94%). Six chemotypes have been identified in these oils. The α-pinene – 1,8-cineole - limonene chemotype was found in the majority of populations. The chemotype of α-pinene - 1,8-cineole - α-terphenyl acetate characterizes the Oued El-Aneb population. The α-pinene - neryl formate - limonene chemotype is observed in the Honaïn population. The remaining populations are characterized by myrtenyl acetate. The essential oils of M. communis were effective against Staphylococcus aureus ATCC 25923, Salmonella enterica ATCC35659, Proteus mirabilis, and Escherichia coli ATCC 25922; however, no significant effect was observed on Klebsiella pneumonia ATCC 700603 and Serratia liquefaciens.

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Chemical Composition and Antimicrobial Activity of the Leaf and Twig Essential Oils of Magnolia hypolampra Growing in Na Hang Nature Reserve, Tuyen Quang Province of Vietnam

Natural Product Communications ◽

10.1177/1934578x19860370 ◽

2019 ◽

Vol 14 (6) ◽

pp. 1934578X1986037

Author(s):

Chu T.T. Ha ◽

Tran H. Thai ◽

Nguyen T. Hien ◽

Ha T.V. Anh ◽

Le N. Diep ◽

...

Keyword(s):

Minimum Inhibitory Concentration ◽

Essential Oil ◽

Essential Oils ◽

Nature Reserve ◽

Inhibitory Concentration ◽

Dry Weight ◽

Gas Chromatography Mass Spectrometry ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Test Microorganism

The leaf and twig essential oils of Magnolia hypolampra, growing wild in Na Hang Nature Reserve, Tuyen Quang province of Vietnam, were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The oil yield calculated on a dry weight basis from leaves of M. hypolampra was very high (1.62%, v/w), while that from twigs was much lower (0.07%, v/w). The essential oils were dominated by monoterpenoids (74.3% and 84.8%) and sesquiterpenoids (24.4% and 13.3%) with β-pinene (36.5% and 41.3%), α-pinene (23.7% and 24.4%), and germacrene D (14.6% and 5.8%) as respective major components. Antibiotic activity of the essential oil samples was tested against Gram-positive bacteria Staphylococcus aureus, Gram-negative bacteria Escherichia coli, and yeast Candida albicans using an agar disk diffusion method. Both the leaf and twig oils showed strong inhibition against all 3 tested microorganism strains with inhibition zones from 18.5 to 30.5 mm and from 45.5 to 46 mm, respectively. Minimum inhibitory concentration of the essential oils was determined using microdilution broth susceptibility assay against 7 test microorganism strains including Bacillus subtilis, Lactobacillus fermentum, Salmonella enterica, Pseudomonas aeruginosa, and 3 abovementioned strains. Minimum inhibitory concentration values of the essential oil from the twigs were from 2.0 to 8.2 mg/mL, while those from the leaves were from 4.1 to 16.4 mg/mL.

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The composition and antibacterial activity of the essential oil of Levisticum officinale Koch. flowers and fruits at different developmental stages

Journal of the Serbian Chemical Society ◽

10.2298/jsc100524126m ◽

2010 ◽

Vol 75 (12) ◽

pp. 1661-1669 ◽

Cited By ~ 13

Author(s):

Mohammad Mirjalili ◽

Peyman Salehi ◽

Ali Sonboli ◽

Javad Hadian ◽

Samad Ebrahimi ◽

...

Keyword(s):

Antibacterial Activity ◽

Essential Oil ◽

Essential Oils ◽

Developmental Stages ◽

Antibacterial Activities ◽

Diffusion Method ◽

Mature Fruit ◽

Disk Diffusion Method ◽

Immature Fruit

The composition and antibacterial activity of the essential oil of Levisticum officinale Koch. at different developmental stages (flower, immature fruit, green mature fruit and ripened fruit) is reported. The essential oils were obtained by hydrodistillation of air-dried samples and their antibacterial activities were tested against seven bacteria. The yield of oil (w/w %) in different stages was in the order: immature fruit (1.5 %) > green mature fruit (1.0 %) > ripened fruit (0.6 %) > flower (0.1 %). The essential oils were analyzed by GC and GC-MS. In total, 27, 31, 28 and 26 constituents were identified and quantified in the mentioned samples, respectively. Monoterpene hydrocarbons were the main group of compounds in the green mature fruit (79.2 %), immature fruit (78.4 %), ripened fruit (75.2 %) and flower (44.0 %). The antibacterial activity of the oils was evaluated by the disk diffusion method using M?ller-Hinton agar and determination of inhibition zones. The results of the bioassays showed some variations between the three tested oils in their inhibitory activity against the tested bacteria at a 10 ?l disc-1 concentration. The oils from mature and ripened fruit exhibited potent antibacterial activity against Bacillus subtilis, with minimum inhibitory concentration (MIC) values of 0.90 mg ml-1 in mature and ripen fruits.

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Comparative study on the phytochemical composition and antibacterial activity of the essential oil of Diphasia klaineana stems at pre-flowering and fruit set

The Journal of Phytopharmacology ◽

10.31254/phyto.2021.10509 ◽

2021 ◽

Vol 10 (5) ◽

pp. 331-337

Author(s):

Benson Boua Boua ◽

◽

Yacouba Koné ◽

Lanciné Traoré ◽

N’Guessan Ambroise Malan ◽

...

Keyword(s):

Antibacterial Activity ◽

Essential Oil ◽

Essential Oils ◽

Fruit Set ◽

Developmental Stages ◽

Antibacterial Activities ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Phytochemical Composition ◽

Staphyloccocus Aureus

The phytochemical composition and antibacterial activity of the essential oils of Diphasia klaineana at different developmental stages (pre-flowering and fruit set) were reported. The essential oils were extracted by continuous hydro distillation and their antibacterial activities were tested against Staphyloccocus aureus ATCC 25923. The yield of oil (w/w %) of stems in different stages was in the order: pre-flowering (0.21 %) > fruit set (0.07 %). GC and GC/MS were analyzed the essential oils composition. In total, 35 and 34 constituents were identified and quantified in the mentioned samples, respectively. Monoterpene hydrocarbons were the main group of compounds in the stems during preflowering (42.40 %) and fruit set (56.15 %). Major compounds at pre-flowering were β-elemol, sabinene, guaiol and terpinen-4-ol. The antibacterial effect of essential oils was estimated by the disk diffusion method using Müller–Hinton agar and the measurement of diameters of inhibition zones. The bioassay results showed some variations between the two tested oils in their inhibitory activity against the tested bacteria at 10 µL. The essential oils from Diphasia klaineana stems at pre-flowering exhibited potent antibacterial activity against Staphyloccocus aureus ATCC 25923, with a minimum inhibitory concentration (MIC) value of 25 mg/mL, while the stems essential oil at fruit set had no activity

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Potential inhibition of essential oils and crude extract of Zingiber species to the growth of Fusarium oxysporum Schlecht f.sp. cubense

Biofarmasi Journal of Natural Product Biochemistry ◽

10.13057/biofar/f010204 ◽

2003 ◽

Vol 1 (2) ◽

pp. 58-64

Author(s):

PURWANTI PURWANTI ◽

SURANTO SURANTO ◽

RATNA SETYANINGSIH

Keyword(s):

Essential Oil ◽

Essential Oils ◽

Fusarium Oxysporum ◽

Crude Extract ◽

Disk Diffusion ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Zingiber Zerumbet ◽

Paper Disk

The aims of this research were (1) to investigate the potency of essential oil and crude extract of rhizome lempuyang pahit (Zingiber amaricans Vahl.), lempuyang gajah (Zingiber zerumbet L.) and lempuyang wangi (Zingiber aromaticum L.) in preventing growth of F. oxysporum f.sp. cubense (2) to determine the proper concentration of essential oil and crude extract in preventing the growth of F. oxysporum f.sp. cubense. Essential oil of rhizome Zingiber spp. was separated by Stahl destilation with methanol solvent. Crude extract was made by soaking the powder of Zingiber spp. in methanol absolute and then filtered by paper disk. Several compounds of rhizome Z. amaricans Vahl. were analysed by GC-MS. Potential inhibition of essential oil and crude extract were examined using disk diffusion method at concentration of 1%, 10%, and 100% respectively, while methanol absolute was used as control and Benlate fungicide was used for comparison. The result showed that essential oil and crude extract of Z. amaricans Vahl. and Z. zerumbet L. were able to inhibit the growth of F. oxysporum f.sp. cubense. Essential oil Z. amaricans Vahl. were also able to inhibit the growth of F. oxysporum f.sp. cubense at lowest concentration of 1% while the Z. zerumbet L. at concentration 10%. Crude extract Z. amaricans Vahl. and Z. zerumbet L. were able to prevent the growth of F. oxysporum f.sp. cubense even at concentration of 100%.

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