Antimicrobial Potential and Chemical Characterization of Serbian Liverwort (Porella arboris-vitae): SEM and TEM Observations

The chemical composition ofPorella arboris-vitaeextracts was determined by solid phase microextraction, gas chromatography-mass spectrometry (SPME GC-MS), and 66 constituents were identified. The dominant compounds in methanol extract ofP.arboris-vitaewereβ-caryophyllene (14.7%),α-gurjunene (10.9%),α-selinene (10.8%),β-elemene (5.6%),γ-muurolene (4.6%), and allo-aromadendrene (4.3%) and in ethanol extract,β-caryophyllene (11.8%),α-selinene (9.6%),α-gurjunene (9.4%), isopentyl alcohol (8.8%), 2-hexanol (3.7%),β-elemene (3.7%), allo-aromadendrene (3.7%), andγ-muurolene (3.3%) were the major components. In ethyl acetate extract ofP.arboris-vitae, undecane (11.3%),β-caryophyllene (8.4%), dodecane (6.4%),α-gurjunene (6%), 2-methyldecane (5.1%), hemimellitene (4.9%), and D-limonene (3.9%) were major components. The antimicrobial activity of differentP.arboris-vitaeextracts was evaluated against selected food spoilage microorganisms using microbroth dilution method. The Minimal Inhibitory Concentration (MIC) varied from 0.5 to 1.5 mg/mL and 1.25 to 2 mg/mL for yeast and bacterial strains, respectively. Significant morphological and ultrastructural alterations due to the effect of methanolic and ethanolicP.arboris-vitaeextracts onS. Enteritidis have also been observed by scanning electron microscope and transmission electron microscope, respectively. The results provide the evidence of antimicrobial potential ofP.arboris-vitaeextracts and suggest its potential as natural antimicrobial agents for food preservation.

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Assessment of the Chemical Composition and In Vitro Antimicrobial Potential of Extracts of the Liverwort Scapania Aspera

Natural Product Communications ◽

10.1177/1934578x1300800932 ◽

2013 ◽

Vol 8 (9) ◽

pp. 1934578X1300800

Author(s):

Danka R. Bukvicki ◽

Amit K. Tyagi ◽

Davide G. Gottardi ◽

Milan M. Veljic ◽

Snezana M. Jankovic ◽

...

Keyword(s):

Chemical Composition ◽

Antimicrobial Agents ◽

Methanol Extract ◽

Solid Phase ◽

Ethanol Extract ◽

Gas Chromatography Mass Spectrometry ◽

Bacterial Strains ◽

Spoilage Microorganisms ◽

Broth Dilution

The chemical composition of Scapania aspera extracts was determined by solid phase micro extraction gas chromatography–mass spectrometry (SPME GC-MS) and 96 constituents were identified. The dominant compounds in the methanol extract were β-barbatene (25.1%), o-cymene (14.0%), α-barbatene (5.7%), allo-aromadendrene (4.9%) and β-bourbonene, while in the ethanol extract, o-cymene (17.8%), β-barbatene (17.6%), α-thujene (6.7%), octen-1-ol acetate (4.9%) and β-bazzanene (2.4%) were the major components. In the ethyl acetate extract, β-barbatene (14.3%), undecane (11.8%), 2-methyldecane (11.2%), decane (10.9%) and o-cymene (3.6%) were major components. The antimicrobial activity of the different extracts was evaluated against pathogenic and food spoilage microorganisms using disc diffusion and micro-broth dilution methods. The minimal inhibitory concentration (MIC) of extracts of S. aspera varied from 0.4 to 1.5 mg/mL and 1 to 3 mg/mL for yeast and bacterial strains, respectively. The zone of inhibition of the methanol extract for yeast strains was higher than that for bacterial strains. The results suggest that S. aspera extracts have potential as natural antimicrobial agents.

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BIOLOGICAL EVALUATION, QSAR AND MOLECULAR MODELING STUDIES OF 2,4-DICHLOROBENZOIC ACID DERIVATIVES AS ANTIMICROBIAL AGENTS

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2019.v12i4.31631 ◽

2019 ◽

pp. 98-105

Author(s):

SAMRIDHI THAKRAL ◽

VIKRAMJEET SINGH

Keyword(s):

Molecular Modeling ◽

Antimicrobial Agents ◽

Structural Characteristics ◽

Docking Simulation ◽

Biological Evaluation ◽

Dilution Method ◽

Bacterial Strains ◽

Qsar Studies ◽

Antimicrobial Potential

Objective: The aim of this study was to evaluate 2,4-dichlorobenzoic acid derivatives as antimicrobial agents through in vitro, QSAR and molecular docking studies. Methods: The compounds were subjected to in vitro antimicrobial screening by test tube dilution method and the structural characteristics governing the antimicrobial potential were studied using QSAR methodology. These compounds were also screened for docking simulation to find out binding confirmation of reported compounds with PDB 1aj0 and 5fsa using AutoDock tools and discovery studio. Results: The antimicrobial evaluation data indicated that compounds 13 and 18 were found to be the most effective against all the bacterial strains and Aspergillus niger while compounds 1 and 14 exhibited more antifungal potential against Candida albicans. QSAR studies confirmed the role of molar refractivity and Balaban index (J) as controlling parameters for antimicrobial potential. Molecular modeling study revealed that compounds interact with the active site of PDB by hydrophobic, hydrogen bonding, and Van der Wall interactions. Conclusion: These test compounds were identified as potent candidates for the control of microbial strains tested, and structural relationship with activity may provide valuable information for further design and synthesis of compounds with antimicrobial potential.

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Antimicrobial Activity and Chemical Characterization of a Non-Polar Extract of Saffron Stamens in Food Matrix

Foods ◽

10.3390/foods10040703 ◽

2021 ◽

Vol 10 (4) ◽

pp. 703

Author(s):

Severino Zara ◽

Giacomo L. Petretto ◽

Alberto Mannu ◽

Giacomo Zara ◽

Marilena Budroni ◽

...

Keyword(s):

Chemical Composition ◽

Fatty Acid Content ◽

Chemical Characterization ◽

Antimicrobial Activities ◽

Added Value ◽

Gas Chromatography Mass Spectrometry ◽

Food Matrix ◽

Bacterial Strains ◽

By Products

The production of saffron spice generates large quantities of plant by-products: over 90% of the plant material collected is discarded, and a consideration fraction of this waste is plant stamens. This work investigated the chemical composition and the antimicrobial activities of the non-polar fraction extracted from four different saffron flower stamens. The chemical composition of ethereal extracts of the saffron stamens was qualitatively assessed by means of gas–chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) analyses. These analyses revealed ethereal extracts to possess a high polyunsaturated fatty acid content. In vitro antibacterial activity of stamen extracts showed no large differences between Gram-positive and Gram-negative bacteria in terms of minimal inhibitory concentration (MIC). In food matrix microbial analysis of the bacterial strains belonging to the main foodborne pathogen species, including Staphylococcus aureus DSM 20231, Escherichia coli DSM 30083, and Listeria monocytogenes DSM 20600, using low-fat UHT milk, revealed a statistically significant reduction in the number of cells (particularly for E. coli and S. aureus with a complete elimination of the population of the two target bacteria following incubation in diethyl ether extracts of saffron stamen (DES) at high concentrations tested, both at 37 °C and 6 °C (for 48 h and 7 days, respectively). A synergic effect was observed when the pathogens were incubated at 6 °C with DES. This work shows these by-products to be excellent sources of bioactive compounds, which could be exploited in high-added-value products, such as food, cosmetics, and drugs.

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Chemical Characterization of Capsule-Brewed Espresso Coffee Aroma from the Most Widespread Italian Brands by HS-SPME/GC-MS

Molecules ◽

10.3390/molecules25051166 ◽

2020 ◽

Vol 25 (5) ◽

pp. 1166

Author(s):

Veronica Lolli ◽

Animesh Acharjee ◽

Donato Angelino ◽

Michele Tassotti ◽

Daniele Del Rio ◽

...

Keyword(s):

Solid Phase Microextraction ◽

Solid Phase ◽

Chemical Characterization ◽

Gas Chromatography Mass Spectrometry ◽

Multivariate Statistical ◽

Espresso Coffee ◽

Volatile Profiles ◽

Few Data ◽

Selection Of

Coffee capsules market is on the rise as it allows access to a wide selection of coffee, differing in taste and brand. However, few data about the chemical characterization of the capsule-brewed coffee aroma are available. In this work, an untargeted approach using headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS) and combined to chemometrics was performed to study and compare aroma profile from 65 capsule-brewed espresso coffees (ECs) commercialized by five of the most representative brands in Italy. Volatile profiles obtained from ECs were subjected to multivariate statistical analysis, which generally did not show a significant variability among coffees belonging to the same brand, except for those modified after the addition of specific flavor additives or aromatic substances (such as caramel, chocolate, etc.). Similarities may be related to the starting coffee brew or the processing method, which is likely the same for each individual brand. Additionally, partial least squares discriminant analysis (PLS-DA) showed that capsules from a specific brand contain the highest concentration of pyrazines, thus characterized by an intense and characteristic aroma, and a stronger note than those from the other brands. This study supports that the chemical analysis in conjunction with chemometric tools is a useful approach for assessing flavor quality, even if the need remains to identify volatile markers of high-quality beverages.

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Essential Oils from Fruit and Vegetables, Aromatic Herbs, and Spices: Composition, Antioxidant, and Antimicrobial Activities

Biology ◽

10.3390/biology10111091 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1091

Author(s):

Soumi De-Montijo-Prieto ◽

María del Carmen Razola-Díaz ◽

Ana María Gómez-Caravaca ◽

Eduardo Jesús Guerra-Hernandez ◽

María Jiménez-Valera ◽

...

Keyword(s):

Antioxidant Activity ◽

Essential Oils ◽

Bacterial Species ◽

Radical Scavenging ◽

Antimicrobial Activities ◽

Food Preservation ◽

Diffusion Method ◽

Dilution Method ◽

Agar Dilution Method ◽

Bacterial Strains

In the field of food preservation, encapsulated Essential Oils (EOs) could be the best non-toxic and eco-friendly tool for food preservative applications substituting the chemicals ones that have several disadvantages for the environment and health. Thirteen commercial EOs from plants, fruits, and vegetables were characterized by GC-MS. The antioxidant activity was measured by DPPH and ABTS techniques. Antimicrobial activity was assessed by agar well-diffusion method and the Minimum Inhibitory Concentration (MIC) by agar dilution method against six bacteria, Candida albicans, and Botrytis cinerea. All the EOs tested have demonstrated antioxidant activity in the range of IC50 0.01–105.32 mg/mL. Between them, cinnamon EOs were the best, followed by oregano and thyme EOs. Fennel EO showed the lowest radical scavenging. MIC values ranged from 0.14 to 9 mg/mL. C. cassia, thyme, and oregano EOs were the most effective against the bacterial species tested, and the yeast C. albicans. On the contrary, citric fruit EOs showed low or no inhibition against most bacterial strains. The percentages of inhibition of mycelia growth of B. cinerea ranged from 3.4 to 98.5%. Thyme, oregano, mint, and fennel EOs showed the highest inhibition.

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Profile of Volatile Compounds in Dessert Yogurts Prepared from Cow and Goat Milk, Using Different Starter Cultures and Probiotics

Foods ◽

10.3390/foods10123153 ◽

2021 ◽

Vol 10 (12) ◽

pp. 3153

Author(s):

Georgia Papaioannou ◽

Ioanna Kosma ◽

Anastasia V. Badeka ◽

Michael G. Kontominas

Keyword(s):

Volatile Compounds ◽

Carboxylic Acids ◽

Lactobacillus Acidophilus ◽

Solid Phase ◽

Goat Milk ◽

Starter Cultures ◽

Cow Milk ◽

Gas Chromatography Mass Spectrometry ◽

Bacterial Strains ◽

Organoleptic Evaluation

The purpose of this study was to determine the profile of volatile compounds (aroma) and overall flavor in dessert yogurts prepared from cow and goat milk, using three different, commercially available starter cultures, in the presence or absence of probiotic bacteria and to correlate this to organoleptic evaluation results obtained using a consumer acceptability method. The extraction of volatile compounds was carried out by solid phase micro-extraction; separation and analysis by gas chromatography-mass spectrometry. Variations among the different classes of compounds (i.e., aldehydes, alcohols, ketones, volatile acids, hydrocarbons, and terpenes) were recorded for different treatments. The results showed that the main volatiles in the cow milk dessert yogurts without Bifidobacterium BB-12 were: acetaldehyde, 2,3-butanedione, 2,3-pentanedione, 3-OH-2-butanone, 2-propanone, hexanoic acid and limonene). Respective volatiles in cow milk dessert yogurts with Bifidobacterium BB-12 were: acetaldehyde, pentanal, hexanal, the same ketones, acetic acid and limonene). The volatiles in goat milk dessert yogurts without Lactobacillus acidophilus LA-5 were: acetaldehyde, the same ketones, no carboxylic acids, limonene, camphene, α- and β-pinene. Respective volatiles in goat milk dessert yogurts with Lactobacillus acidophilus LA-5 were: aldehydes acetaldehyde, the same ketones, butanoic acid, α-pinene and camphene varying in concentration in different samples. Based on the results of volatiles and organoleptic evaluation, it can be concluded that dessert yogurts from cow milk without probiotic bacterial strains using the mild and classic starter cultures, and dessert yogurts from goat milk with probiotic bacterial strains using the classic and acidic starter cultures are found to be more organoleptically acceptable by consumers. In most cases, a positive correlation was found between dessert yogurt organoleptically determined flavor and volatiles (aldehydes, ketones and carboxylic acids).

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Design, Synthesis, Docking and Computational Pharmacokinetic Profiling of New Pyrazolinyl Thiazolinone Biheterocycles as Potent Antimicrobial Agents

Letters in Drug Design & Discovery ◽

10.2174/1570180817999200623115049 ◽

2020 ◽

Vol 17 (11) ◽

pp. 1342-1354

Author(s):

Vinutha Vittala Salian ◽

Badiadka Narayana ◽

Balladka Kunhanna Sarojini ◽

Sharath Chandra Kodandoor ◽

Anupam Glorious Lobo

Keyword(s):

Antifungal Activity ◽

Active Sites ◽

Antimicrobial Agents ◽

Building Blocks ◽

Diffusion Method ◽

Dilution Method ◽

Bacterial Strains ◽

Design Synthesis ◽

Reference Drug ◽

Fungal Strains

Background: Development of potential antimicrobial agents is the main aim in the drug discovery process to overcome the problem of drug resistance. Pyrazolines and thiazolinones are extensively used as building blocks for the synthesis of diverse and medicinally important compounds. Methods: In this present work, a new series of functionalized pyrazolinyl-thiazolinone biheterocycles is designed and synthesized from N-pyrazolinecarbothioamide. Antimicrobial screening is carried out in order to discover their potential towards six bacterial and four fungal strains. The zone of inhibition (ZI in mm) was determined by the disc diffusion method and minimum inhibitory concentration (MIC in μg/mL) by macro dilution method. The druggability of these new entities is done through in silico pharmacokinetic profiling using Maestro 2017-1 interface of Schrӧdinger software. Results and Disscusion: Compounds 4c and 4e with chloro and iodo substituents on Nphenylacetamide ring displayed good inhibitory antibacterial activity against the tested bacterial strains with minimum MIC values when compared to the reference drug tetracycline. Compound 3 with an acetic acid derivative showed high antifungal activity among all the tested derivatives. Compound 3 not only showed antifungal activity but also qualified druggability test with no violation of Lipinski rule of five. Conclusion: The capability of the synthesized pyrazolinyl-thiazolinone derivatives was performed to efficiently inhibit the growth of microorganisms against selected bacterial and fungal strains. Further, these compounds are found to be effectively bound to the active sites of attractive target Escherichia coli FabH.

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Reduction of aldehydes and terpenes within pine wood by microbial activity

Holzforschung ◽

10.1515/hf-2015-0243 ◽

2016 ◽

Vol 70 (9) ◽

pp. 895-900 ◽

Cited By ~ 8

Author(s):

Bernhard Widhalm ◽

Thomas Ters ◽

Ewald Srebotnik ◽

Cornelia Rieder-Gradinger

Keyword(s):

Gas Chromatography ◽

Solid Phase ◽

Complete Removal ◽

Growth Conditions ◽

Raw Material ◽

Gas Chromatography Mass Spectrometry ◽

Bacterial Strains ◽

Pine Wood ◽

Wood Processing ◽

Wood Particles

Abstract Aldehydes and terpenes are the most frequently emitted volatile organic compounds (VOCs) in the wood-processing industry. These emissions are classified as injurious to health and hazardous to the environment. To address this problem, the growth conditions have been identified under which bacteria extensively degrade both aldehydes and particularly terpenes in pine wood particles as a raw material for the production of particle boards. In this study, the focus was on pentanal and hexanal (aldehydes) as well as α- and β-pinene (terpenes). Bacterial strains were selected for their ability to metabolize α-pinene as single carbon source in liquid culture medium. α-Pinene degradation was then determined by gas chromatography (GC) analysis. Strains belonging to the genus Pseudomonas showed the best results (98% degradation after 72 h). Comparably good results were also achieved with the thermophilic strain Bacillus pallidus (90% degradation) at 55°C. Furthermore, an adapted mixed culture of Pseudomonas species was inoculated onto wood particles and incubated at room temperature for 3 days. Solid-phase microextraction (SPME) measurements of emitted volatiles and subsequent gas chromatography-mass spectrometry (GC-MS) analysis indicated a complete removal (100%) of aldehydes and, even more importantly, α- and β-pinene. Pre-treatment of unsterile pine wood particles with Pseudomonas species may have potential for industrial application.

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Activities of Synthetic Hybrid Peptides against Anaerobic Bacteria: Aspects of Methodology and Stability

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.1.68-72.2000 ◽

2000 ◽

Vol 44 (1) ◽

pp. 68-72 ◽

Cited By ~ 41

Author(s):

Herin Oh ◽

Maria Hedberg ◽

David Wade ◽

Charlotta Edlund

Keyword(s):

Pathogenic Bacteria ◽

Antimicrobial Agents ◽

Anaerobic Bacteria ◽

Accurate Method ◽

Dilution Method ◽

Bacterial Strains ◽

Hybrid Peptides ◽

Anaerobic Infections ◽

The Stability

ABSTRACT The increasing problem of antibiotic resistance among pathogenic bacteria requires development of new antimicrobial agents. One line of investigation is the synthesis of antimicrobial hybrid peptides. The aim of the present investigation was to determine the in vitro activities of 16 cecropin-melittin hybrid peptides (CAMEL analogues) against 60 anaerobic bacterial strains, to compare their activities with those of seven clinically used antimicrobial agents, and to compare different methods for anaerobic susceptibility testing of these peptides. The stability of one of the peptides, temporin B, with different stereoisomeric configurations was investigated in a fecal milieu. The CAMEL analogues showed antimicrobial activity against the anaerobic bacteria, with MICs ranging from 0.125 to 32 μg/ml. The overall activities (the MICs at which 90% of isolates are inhibited) of the CAMEL analogues against anaerobic bacteria were mainly inferior to those of imipenem, clindamycin, and piperacillin but were equal to or superior to those of metronidazole, cefoxitin, ciprofloxacin, and chloramphenicol. The agarose dilution method was found to be an accurate method for the testing of large numbers of bacterial strains. The d isomer of temporin B was inactivated more slowly in feces than the l isomer. This study shows that the CAMEL analogues are potential agents for the treatment of anaerobic infections.

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MoO₃ Nano-Bricks as Novel Antimicrobial Agents

European Journal of Biology and Biotechnology ◽

10.24018/ejbio.2020.1.6.134 ◽

2020 ◽

Vol 1 (6) ◽

Author(s):

Saleh B. Alghamdi

Keyword(s):

Textile Industry ◽

Antimicrobial Agents ◽

Multiple Drug Resistance ◽

Antibacterial Properties ◽

Physicochemical Characterization ◽

Model Organism ◽

Multiple Drug ◽

Molybdenum Oxides ◽

Bacterial Strains ◽

Antimicrobial Potential

Multiple drug resistance in microorganisms has impersonated critical vulnerability to existing antibiotics; hence substitutes/or options to encounter resistant pathogenic microbes are desirable. Our focus in this study was the synthesis and characterization of Molybdenum oxide (MoO3) nano-bricks and to explore them in terms of their antimicrobial potential. MoO3 nano-bricks were successfully synthesized by hydrothermal method using (NH4)6Mo7O24⋅4H2O precursor and calcination at 500 °C for 2 h. The synthesized MoO3 nano-bricks determined antibacterial activity against four bacterial isolates and one fungal isolate. The MoO3 bricks were characterized using standard physicochemical characterization viz. XRD, SEM, FTIR, and EDX. In the present investigation, characteristic antibacterial properties of MoO3 nano-bricks against Gram +ve (S. aureus ATCC 29213 and S. epidermidis ATCC 12228) and Gram -ve (E. coli ATCC 35218 and K. pneumoniae ATCC 700603) bacteria is noted. The antifungal activity was tested using C. albicans ATCC 10231 as model organism. Molybdenum oxides generate acidic medium and demonstrated potent antimicrobial action for various pathogenic bacterial strains causing infections. The MoO3 nano-bricks depicted broad spectrum antimicrobial potential which strongly recommends their use as material of choice as potential antimicrobial material to be used in food industry, water purification, textile industry etc.

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