Plant antimicrobial peptides: structures, functions, and applications

AbstractAntimicrobial peptides (AMPs) are a class of short, usually positively charged polypeptides that exist in humans, animals, and plants. Considering the increasing number of drug-resistant pathogens, the antimicrobial activity of AMPs has attracted much attention. AMPs with broad-spectrum antimicrobial activity against many gram-positive bacteria, gram-negative bacteria, and fungi are an important defensive barrier against pathogens for many organisms. With continuing research, many other physiological functions of plant AMPs have been found in addition to their antimicrobial roles, such as regulating plant growth and development and treating many diseases with high efficacy. The potential applicability of plant AMPs in agricultural production, as food additives and disease treatments, has garnered much interest. This review focuses on the types of plant AMPs, their mechanisms of action, the parameters affecting the antimicrobial activities of AMPs, and their potential applications in agricultural production, the food industry, breeding industry, and medical field.

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Studies on bioactive bis-1,3,5-triazinyl dithiocarbamates

Journal of the Serbian Chemical Society ◽

10.2298/jsc0707635l ◽

2007 ◽

Vol 72 (7) ◽

pp. 635-641 ◽

Cited By ~ 3

Author(s):

V.D. Lunagariya ◽

R.M. Desai ◽

V.H. Shah

Keyword(s):

Antimicrobial Activity ◽

Nmr Spectroscopy ◽

1H Nmr Spectroscopy ◽

Antimicrobial Activities ◽

Gram Negative Bacteria ◽

Plate Method ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Elemental Analyses ◽

Bacteria And Fungi

The compounds bis(4,6-dichloro/bis[(p-methoxyphenyl)amino]-1,3,5- -triazin-2-yl)1,2-hydrazine-1,2-dicarbodithioate/1,4-phenylenebis(carbamodithioate)/( 1,1?-biphenyl)-4,4?-diylbis(carbamodithioate)/(sulphonyldi-4,1-phenylene)- bis(carbamodithioate/1,2-ethanediylbis(carbamothioate) 4a-j were synthesized by two different methods. In the first method (A) for the preparation of 4a-e, 2,4,6- trichloro-1,3,5-triazine 1 was condensed with diammonium 1,2-hydrazine-1,2-dicarbodithioate/ 1,4-phenylenebis(carbamodithioate)/(1,1?-biphenyl)-4,4?diylbis(carbamodithioate)/( sulphonyl-di-4,1-phenylene)-bis(carbamodithioate)/1,2-ethanediylbis(carbamodithioate) 3a-e to afford 4a-e which undergo reaction with p-methoxyaniline to afford 4f-j. In the second method (B) of preparation, 1 was condensed with p-methoxyaniline to yield 2 followed by the action of 3a-e to yield 4a-j. The structure of the newly synthesized compounds 4a-j was established on the basis of elemental analyses, as well as IR and 1H-NMR spectroscopy. The antimicrobial activities of compounds 4a-j were determined by the cup-plate method against gram-positive bacteria, gram-negative bacteria and fungi. All the synthesized compounds showed significant antimicrobial activity.

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Volatiles from Selected Apiaceae Species Cultivated in Poland—Antimicrobial Activities

Processes ◽

10.3390/pr9040695 ◽

2021 ◽

Vol 9 (4) ◽

pp. 695

Author(s):

Jaroslaw Widelski ◽

Konstantia Graikou ◽

Christos Ganos ◽

Krystyna Skalicka-Wozniak ◽

Ioanna Chinou

Keyword(s):

Antimicrobial Activity ◽

Essential Oils ◽

Antimicrobial Agents ◽

Antimicrobial Activities ◽

Gas Chromatography Mass Spectrometry ◽

Gram Positive ◽

Ongoing Research ◽

Gram Positive Bacteria ◽

Aerial Parts ◽

Bacteria And Fungi

As part of our ongoing research on phytoconstituents that can act as promising antimicrobial agents, the essential oils of nine selected Apiaceae plants, cultivated in Poland, were studied. The volatiles of the aerial parts with fruits (herba cum fructi) of Silaum silaus, Seseli devenyense, Seseli libanotis,Ferula assa-foetida, Glehnia littoralis and Heracleum dulce, in addition to the fruits (fructi) of Torilis japonica and Orlaya grandiflora as well as of the aerial parts (herba) of Peucedanum luxurians were investigated through Gas Chromatography–Mass Spectrometry to identify more than 60 different metabolites. The essential oils from S. devenyense, H. dulce, T. japonica and P. luxurians are reported for the first time. All examined species were also assayed for their antimicrobial activities against several human pathogenic Gram-positive and -negative bacteria and fungi. The species H. dulce, S. devenyense and S. libanotis exerted the strongest antimicrobial activity, mostly against Gram-positive bacteria strains (MIC values 0.90–1.20 mg/mL). To the best of our knowledge, this is the first attempt to determine the antimicrobial activity of the above Apiaceae species.

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Impact of Altitudinal Variation on the Phytochemical Profile, Anthelmintic and Antimicrobial Activity of Two Pinus Species

Molecules ◽

10.3390/molecules26113170 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3170

Author(s):

Wafaa M. Elkady ◽

Mariam H. Gonaid ◽

Miriam F. Yousif ◽

Mahmoud El-Sayed ◽

Hind A. N. Omar

Keyword(s):

Antimicrobial Activity ◽

Essential Oils ◽

Pinus Halepensis ◽

Biological Activities ◽

Anthelmintic Activity ◽

Antimicrobial Activities ◽

Pinus Pinea ◽

Active Components ◽

Pinus Species ◽

Bacteria And Fungi

Active components from natural sources are the current focus in most pharmacological research to provide new therapeutic agents for clinical use. Essential oils from the Pinus species have been traditionally used in medicine. This study aimed to investigate the chemical profile of two Pinus species, Pinus halepensis L. and Pinus pinea Mill, from different altitudes in Libya and study the effect of environmental conditions on the biological activities of essential oils. A clevenger apparatus was used to prepare the essential oils by hydrodistillation. Analyses were done using GC/MS. Anthelmintic and antimicrobial activities were tested against the earthworm Allolobophora caliginosa, gram-positive bacteria, gram-negative bacteria, and fungi. Different chemical profiles were observed among all tested essential oils, and terpenes were the most dominant class. All studied essential oils from the Pinus species exhibited a remarkable anthelmintic activity compared to the standard piperazine citrate drug. Pinus halepensis from both altitudes showed broad-spectrum antimicrobial activity against all tested microorganisms, while Pinus pinea was effective against only Escherichia coli. From these findings, one can conclude that there are variations between studied species. The essential oil compositions are affected by environmental factors, which consequently affect the anthelmintic and antimicrobial activity.

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Characterization of Leader Processing Shows That Partially Processed Mersacidin Is Activated by AprE After Export

Frontiers in Microbiology ◽

10.3389/fmicb.2021.765659 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jakob H. Viel ◽

Amanda Y. van Tilburg ◽

Oscar P. Kuipers

Keyword(s):

Antimicrobial Activity ◽

Synthetic Biology ◽

Heterologous Expression ◽

Expression System ◽

Heterologous Expression System ◽

Proteolytic Activation ◽

E Coli ◽

Gram Positive Bacteria ◽

Precursor Peptide ◽

Potential Applications

The ribosomally synthesized and post-translationally modified peptide mersacidin is a class II lanthipeptide with good activity against Gram-positive bacteria. The intramolecular lanthionine rings, that give mersacidin its stability and antimicrobial activity, are specific structures with potential applications in synthetic biology. To add the mersacidin modification enzymes to the synthetic biology toolbox, a heterologous expression system for mersacidin in Escherichia coli has recently been developed. While this system was able to produce fully modified mersacidin precursor peptide that could be activated by Bacillus amyloliquefaciens supernatant and showed that mersacidin was activated in an additional proteolytic step after transportation out of the cell, it lacked a mechanism for clean and straightforward leader processing. Here, the protease responsible for activating mersacidin was identified and heterologously produced in E. coli, improving the previously reported heterologous expression system. By screening multiple proteases, the stringency of proteolytic activity directly next to a very small lanthionine ring is demonstrated, and the full two-step proteolytic activation of mersacidin was elucidated. Additionally, the effect of partial leader processing on diffusion and antimicrobial activity is assessed, shedding light on the function of two-step leader processing.

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Chemical Compositions and Antimicrobial Activity of the Essential Oils of Piper abbreviatum, P. erecticaule and P. lanatum (Piperaceae)

Natural Product Communications ◽

10.1177/1934578x1400901235 ◽

2014 ◽

Vol 9 (12) ◽

pp. 1934578X1400901 ◽

Cited By ~ 1

Author(s):

Wan Mohd Nuzul Hakimi Wan Salleh ◽

Farediah Ahmad ◽

Khong Heng Yen

Keyword(s):

Antimicrobial Activity ◽

Essential Oils ◽

Antimicrobial Agents ◽

Antimicrobial Activities ◽

Dilution Method ◽

Chemical Compositions ◽

Gram Positive Bacteria ◽

Aerial Parts ◽

Ms Analysis ◽

Weak Activity

The study was designed to examine the chemical composition and antimicrobial activities of essential oils extracted from the aerial parts of three Piper species: Piper abbreviatum, P. erecticaule and P. lanatum, all from Malaysia. GC and GC/MS analysis showed qualitative and quantitative differences between these oils. GC and GC-MS analysis of P. abbreviatum, P. erecticaule and P. lanatum oils resulted in the identification of 33, 35 and 39 components, representing 70.5%, 63.4% and 78.2% of the components, respectively. The major components of P. abbreviatum oil were spathulenol (11.2%), ( E)-nerolidol (8.5%) and β-caryophyllene (7.8%), whereas P. erecticaule oil mainly contained β-caryophyllene (5.7%) and spathulenol (5.1%). Borneol (7.5%), β-caryophyllene (6.6%) and α-amorphene (5.6%) were the most abundant components in P. lanatum oil. Antimicrobial activity was carried out using disc diffusion and broth micro-dilution method against nine microorganisms. All of the essential oils displayed weak activity towards Gram-positive bacteria with MIC values in the range 250–500 μg/mL. P. erecticaule oil showed the best activity on Aspergillus niger (MIC 31.3 μg/mL), followed by P. lanatum oil (MIC 62.5 μg/mL). This study demonstrated that the essential oils have potential as antimicrobial agents and may be useful in the pharmaceutical and cosmetics industries.

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Screening of Antimicrobial Activity and Cytotoxic Effects of Two Cladonia Species

Zeitschrift für Naturforschung C ◽

10.1515/znc-2013-5-604 ◽

2013 ◽

Vol 68 (5-6) ◽

pp. 191-197 ◽

Cited By ~ 2

Author(s):

Birkan Açıkgöz ◽

İskender Karaltı ◽

Melike Ersöz ◽

Zeynep M. Coşkun ◽

Gülşah Çobanoğlu ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antimicrobial Activities ◽

Chloroform Extract ◽

Cytotoxic Effects ◽

Minimal Inhibitory Concentrations ◽

E Coli ◽

Methanol Extracts ◽

Gram Positive Bacteria

The present study explores the antimicrobial activity and cytotoxic effects in culture assays of two fruticose soil lichens, Cladonia rangiformis Hoffm. and Cladonia convoluta (Lamkey) Cout., to contribute to possible pharmacological uses of lichens. In vitro antimicrobial activities of methanol and chloroform extracts against two Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli), two Gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus), and the yeast Candida albicans were examined using the paper disc method and through determination of minimal inhibitory concentrations (MICs). The data showed the presence of antibiotic substances in the chloroform and the methanol extracts of the lichen species. The chloroform extracts exhibited more signifi cant antimicrobial activity than the methanol extracts. However, a higher antifungal activity was noted in the methanol extract of C. rangiformis. The maximum antimicrobial activity was recorded for the chloroform extract of C. convoluta against E. coli. The cytotoxic effects of the lichen extracts on human breast cancer MCF-7 cells were evaluated by the trypan blue assay yielding IC50 values of ca. 173 and 167 μg/ml for the extracts from C. rangiformis and C. convoluta, respectively.

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Inhibitory Spectra and Modes of Antimicrobial Action of Gallotannins from Mango Kernels (Mangifera indicaL.)

Applied and Environmental Microbiology ◽

10.1128/aem.02521-10 ◽

2011 ◽

Vol 77 (7) ◽

pp. 2215-2223 ◽

Cited By ~ 62

Author(s):

Christina Engels ◽

Andreas Schieber ◽

Michael G. Gänzle

Keyword(s):

Staphylococcus Aureus ◽

Wild Type Strain ◽

Antimicrobial Activities ◽

Resistance Mechanisms ◽

Gram Negative Bacteria ◽

Wild Type ◽

Gram Positive Bacteria ◽

Food Borne ◽

Membrane Bound ◽

Bacteria And Fungi

ABSTRACTThis study investigated the antimicrobial activities and modes of action of penta-, hexa-, hepta-, octa-, nona-, and deca-O-galloylglucose (gallotannins) isolated from mango kernels. The MICs and minimum bactericidal concentrations (MBCs) against food-borne bacteria and fungi were determined using a critical dilution assay. Gram-positive bacteria were generally more susceptible to gallotannins than were Gram-negative bacteria. The MICs of gallotannins againstBacillus subtilis,Bacillus cereus,Clostridium botulinum,Campylobacter jejuni,Listeria monocytogenes, andStaphylococcus aureuswere 0.2 g liter−1or less; enterotoxigenicEscherichia coliandSalmonella entericawere inhibited by 0.5 to 1 g liter−1, and lactic acid bacteria were resistant. The use of lipopolysaccharide mutants ofS. entericaindicated that the outer membrane confers resistance toward gallotannins. Supplementation of LB medium with iron eliminated the inhibitory activity of gallotannins againstStaphylococcus aureus, and siderophore-deficient mutants ofS. entericawere less resistant toward gallotannins than was the wild-type strain. Hepta-O-galloylglucose sensitizedLactobacillus plantarumTMW1.460 to hop extract, indicating inactivation of hop resistance mechanisms, e.g., the multidrug resistance (MDR) transporter HorA. Carbohydrate metabolism ofLactococcus lactisMG1363, a conditionally respiring organism, was influenced by hepta-O-galloylglucose when grown under aerobic conditions and in the presence of heme but not under anaerobic conditions, indicating that gallotannins influence the respiratory chain. In conclusion, the inhibitory activities of gallotannins are attributable to their strong affinity for iron and likely additionally relate to the inactivation of membrane-bound proteins.

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Screening of antimicrobial activity of essential oil and methanol extract of Satureja hortensis on foodborne bacteria and fungi

Czech Journal of Food Sciences ◽

10.17221/753-cjfs ◽

2008 ◽

Vol 25 (No. 2) ◽

pp. 81-89 ◽

Cited By ~ 43

Author(s):

A. Adiguzel ◽

H. Ozer ◽

H. Kilic ◽

B. Cetin

Keyword(s):

Antimicrobial Activity ◽

Chemical Composition ◽

Minimum Inhibitory Concentration ◽

Essential Oil ◽

Inhibitory Concentration ◽

Methanol Extract ◽

Antimicrobial Activities ◽

Satureja Hortensis ◽

Bacteria And Fungi

The present work reports the in vitro antimicrobial activities of the essential oil and methanol extract from Satureja hortensis as well as the content of its essential oil. The chemical composition of hydrodistilled essential oil of Satureja hortensis was analysed by means of GC-MS. Thirty constituents were identified. The main constituents of the oil were thymol (40.54%), γ-terpinene (18.56%), carvacrol (13.98%), and p-cymene (8.97). The essential oil of Satureja hortensis exhibited the activity against 25 bacteria, 8 fungi, and a yeast, C. albicans; exerting the Minimum Inhibitory Concentration values (MIC) ranging from 15.62 to 250 µl/ml. Similarly, methanol extract of the plant also showed antimicrobial activity.

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Chemical Hydrogels Bearing Thiazolium Groups with a Broad Spectrum of Antimicrobial Behavior

Polymers ◽

10.3390/polym12122853 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2853 ◽

Cited By ~ 1

Author(s):

Alexandra Muñoz-Bonilla ◽

Jakub Zagora ◽

Daniela Plachá ◽

Coro Echeverría ◽

Alberto Chiloeches ◽

...

Keyword(s):

Antimicrobial Activity ◽

Water Solution ◽

Thermal Polymerization ◽

Inert Atmosphere ◽

Gram Negative Bacteria ◽

Monomer Content ◽

Bacteria And Fungi ◽

Thermal Stability Of ◽

Potential Antimicrobial Activity ◽

Positively Charged

Several hydrogels based on 2-hydroxyethyl methacrylate and a methacrylic monomer containing a thiazole group in its lateral chain have been prepared by thermal polymerization at 60 °C in water solution varying the chemical composition of the gels. The posterior quaternization of the thiazole groups with methyl iodine has rendered positively charged hydrogels with potential antimicrobial activity. This modification has been structurally characterized by infrared spectroscopy, whereas the thermal stability of all hydrogels has been studied by thermal degradation in inert atmosphere. The swelling behavior in distilled water and the rheology of the different hydrogels have been analyzed as a function of 2-(4-methylthiazol-5-yl)ethyl methacrylate (MTA) monomer content as well as its methylation. Finally, the active character of hydrogels against Gram-positive and Gram-negative bacteria and fungi has been evaluated, revealing excellent antimicrobial activity against all tested microorganisms. The methylated hydrogels could be used as potential materials for wound healing or contact lens applications.

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Synthesis and Evaluation of Antimicrobial and Cytotoxic Activity of Oxathiine-Fused Quinone-Thioglucoside Conjugates of Substituted 1,4-Naphthoquinones

Molecules ◽

10.3390/molecules25163577 ◽

2020 ◽

Vol 25 (16) ◽

pp. 3577

Author(s):

Yuri E. Sabutski ◽

Ekaterina S. Menchinskaya ◽

Ludmila S. Shevchenko ◽

Ekaterina A. Chingizova ◽

Artur R. Chingizov ◽

...

Keyword(s):

Antimicrobial Activity ◽

Cytotoxic Activity ◽

Antimicrobial Activities ◽

Biologically Active ◽

Hydroxyl Group ◽

Diffusion Method ◽

Gram Positive ◽

Gram Positive Bacteria ◽

High Cytotoxic Activity ◽

Derivatives Of

A series of new tetracyclic oxathiine-fused quinone-thioglycoside conjugates based on biologically active 1,4-naphthoquinones and 1-mercapto derivatives of per-O-acetyl d-glucose, d-galactose, d-xylose, and l-arabinose have been synthesized, characterized, and evaluated for their cytotoxic and antimicrobial activities. Six tetracyclic conjugates bearing a hydroxyl group in naphthoquinone core showed high cytotoxic activity with EC50 values in the range of 0.3 to 0.9 μM for various types of cancer and normal cells and no hemolytic activity up to 25 μM. The antimicrobial activity of conjugates was screened against Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus), Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli), and fungus Candida albicans by the agar diffusion method. The most effective juglone conjugates with d-xylose or l-arabinose moiety and hydroxyl group at C-7 position of naphthoquinone core at concentration 10 µg/well showed antimicrobial activity comparable with antibiotics vancomicin and gentamicin against Gram-positive bacteria strains. In liquid media, juglone-arabinosidic tetracycles showed highest activity with MIC 6.25 µM. Thus, a positive effect of heterocyclization with mercaptosugars on cytotoxic and antimicrobial activity for group of 1,4-naphthoquinones was shown.

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