Influence of Glassy or Rubbery State on the Antimicrobial Activity of Chitosan-gelatin Films

The aim was to study if the antimicrobial activity of chitosan incorporated into edible films based on gelatin could be affected by the molecular mobility (glassy or rubbery state) of the matrix. Films were obtained from film-forming suspensions (FFS) of bovine and salmon gelatins (7% w/w) and chitosan (0; 0.25; 0.5; 1% w/w) equilibrated at 33% y 85% of relative humidities. Antimicrobial properties against Escherichia coli, Listeria monocytogenes and Salmonella thyphimurium were determined. The results showed that both FFS and films had antimicrobial effects related to chitosan concentration. This besides depended on their glass and rubber film state, being in the initially glassy state for salmon 66% higher than bovine in comparison to the rubbery state (8%). This was mainly due to the highest moisture uptake (1.82±0.02% water absorbed/min) for glassy state. Therefore, the molecular mobility of the matrix film affected the antimicrobial activity of chitosan in chitosan-gelatin films.

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Basil Essential Oil: Composition, Antimicrobial Properties, and Microencapsulation to Produce Active Chitosan Films for Food Packaging

Foods ◽

10.3390/foods10010121 ◽

2021 ◽

Vol 10 (1) ◽

pp. 121

Author(s):

Ghita Amor ◽

Mohammed Sabbah ◽

Lucia Caputo ◽

Mohamed Idbella ◽

Vincenzo De Feo ◽

...

Keyword(s):

Antimicrobial Activity ◽

Essential Oil ◽

Shelf Life ◽

Food Packaging ◽

Antimicrobial Properties ◽

Edible Films ◽

Biological Properties ◽

Oil Composition ◽

Packaging System ◽

Cooked Ham

The essential oil (EO) from basil—Ocimum basilicum—was characterized, microencapsulated by vibration technology, and used to prepare a new type of packaging system designed to extend the food shelf life. The basil essential oil (BEO) chemical composition and antimicrobial activity were analyzed, as well as the morphological and biological properties of the derived BEO microcapsules (BEOMC). Analysis of BEO by gas chromatography demonstrated that the main component was linalool, whereas the study of its antimicrobial activity showed a significant inhibitory effect against all the microorganisms tested, mostly Gram-positive bacteria. Moreover, the prepared BEOMC showed a spheroidal shape and retained the EO antimicrobial activity. Finally, chitosan-based edible films were produced, grafted with BEOMC, and characterized for their physicochemical and biological properties. Since their effective antimicrobial activity was demonstrated, these films were tested as packaging system by wrapping cooked ham samples during 10 days of storage, with the aim of their possible use to extend the shelf life of the product. It was demonstrated that the obtained active film can both control the bacterial growth of the cooked ham and markedly inhibit the pH increase of the packaged food.

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Edible films gelatin-based obtained from mahi-mahi skin (Coryphaena hippurus) and oregano extract: Physicochemical, antimicrobial, structural and surface characteristics

Scientia Agropecuaria ◽

10.17268/sci.agropecu.2021.026 ◽

2021 ◽

Vol 12 (2) ◽

pp. 229-237

Author(s):

Silvia Pandia-Estrada ◽

Renzo Romero-Santivañez ◽

Roxana Céspedes-Chombo ◽

Armando Solari-Godiño

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Antimicrobial Activity ◽

Lipid Fraction ◽

Surface Characteristics ◽

Edible Films ◽

Proteus Vulgaris ◽

Coryphaena Hippurus ◽

Film Forming ◽

Scanning Electron

Edible films were elaborated from gelatin solutions (4% w/v) of mahi-mahi skin (Coryphaena hippurus) with 2,5; 5; 7,5 and 10% v/v of oregano extract (OE) and its physicochemical, antimicrobial, structural and surface properties were determined. The control and with 2.5% OE films showed the lowest moisture and opacity values and the highest viscosity values. All films with OE inhibited the growth of Staphylococcus aureus and Proteus vulgaris. Alone films with 10% OE showed antimicrobial activity against all the strains evaluated. Scanning electron microscopy showed that the incorporation of oregano extract in the film-forming solutions, FFS, was related to an increase in the presence of oil droplets in the films, showing the lipid fraction of OE. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyzes showed the interaction between gelatin, plasticizer, and oregano extract in all films. In conclusion, this study demonstrated the viability of mahi-mahi skin gelatin edible films with OE incorporated for their application as packaging with antimicrobial action in foods susceptible to spoilage by microorganisms.

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Physicochemical and Antimicrobial Properties of Whey Protein-Based Films Functionalized with Palestinian Satureja capitata Essential Oil

Coatings ◽

10.3390/coatings11111364 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1364

Author(s):

Manar Abdalrazeq ◽

Nidal Jaradat ◽

Mohammad Qadi ◽

C. Valeria L. Giosafatto ◽

Eliana Dell’Olmo ◽

...

Keyword(s):

Antimicrobial Activity ◽

Essential Oil ◽

Food Packaging ◽

Pathogenic Bacteria ◽

Whey Proteins ◽

Antimicrobial Properties ◽

Wild Plants ◽

Gram Negative Bacteria ◽

Elongation At Break ◽

Film Forming

The present study aimed to produce bio-active packaging materials made of whey proteins (WPs) and essential oil (EO) extracted from Thymbra (Satureja capitata, L.), one of the most popular Palestinian wild plants. In this study, two different Thymbra leaves from Nablus and Qabatiya in Palestine were collected and analyzed for EOs by gas chromatography and mass spectrometry. Based on the analysis, two EOs, namely, TEO1 and TEO2, were extracted, and it was found that both samples primarily contain γ-terpinene and carvacrol, whereas p-cymene was detected only in TEO1. The antimicrobial activity of TEO1 and TEO2 was evaluated by microbroth microdilution assays against pathogenic bacteria and yeast. Based on the results, TEO1 exhibited potent antimicrobial activity against the test strains. Besides, TEO1 was chosen to functionalize WP-based films at different concentrations (0.1%, 0.4%, and 0.8% v/v of Film Forming Solutions). Film mechanical property investigation showed a marked reduction in the tensile strength and Young’s modulus at 0.8% TEO1. In contrast, its elongation at break value was significantly (p < 0.05) increased due to the plasticizing effect of the EO. Moreover, the film transparency was found to be significantly (p < 0.05) reduced by increasing TEO1 concentrations. Finally, microbiological investigations indicated that film antimicrobial activity against both gram-positive and gram-negative bacteria increased dose-dependently. The overall results open interesting perspectives for employing these films as preservative materials in food packaging.

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How dry is dry? Molecular mobility in relation to thallus water content in a lichen

Journal of Experimental Botany ◽

10.1093/jxb/eraa521 ◽

2020 ◽

Author(s):

Fabio Candotto Carniel ◽

Beatriz Fernandez-Marín ◽

Erwann Arc ◽

Teresa Craighero ◽

José Manuel Laza ◽

...

Keyword(s):

Water Content ◽

Molecular Mobility ◽

Glassy State ◽

Life Forms ◽

Poor Knowledge ◽

Rubbery State ◽

Downstream Effects ◽

Flavoparmelia Caperata ◽

Water Contents ◽

Thallus Water Content

Abstract Lichens can withstand extreme desiccation to water contents of ≤ 0.1 g H2O g–1 DW, and in the desiccated state are among the most extremotolerant organisms known. Desiccation-tolerant life-forms such as seeds, mosses and lichens survive ‘vitrification’, that is the transition of their cytoplasm to a ‘glassy’ state, which causes metabolism to cease. However, our understanding of the mechanisms of desiccation tolerance is hindered by poor knowledge of what reactions occur in the desiccated state. Using Flavoparmelia caperata as a model lichen, we determined at what water contents vitrification occurred upon desiccation. Molecular mobility was assessed by dynamic mechanical thermal analysis, and the de- and re-epoxidation of the xanthophyll cycle pigments (measured by HPLC) was used as a proxy to assess enzyme activity. At 20 °C vitrification occurred between 0.12–0.08 g H2O g−1 DW and enzymes were active in a ‘rubbery’ state (0.17 g H2O g−1 DW) but not in a glassy state (0.03 g H2O g−1 DW). Therefore, desiccated tissues may appear to be ‘dry’ in the conventional sense, but subtle differences in water content will have substantial consequences on the types of (bio)chemical reactions that can occur, with downstream effects on longevity in the desiccated state.

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Heat Effect on Antimicrobial Properties of Plasticizer PEG Blended Chitosan

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.804.203 ◽

2015 ◽

Vol 804 ◽

pp. 203-206

Author(s):

Duongruitai Nicomrat ◽

Jirasak Tharajak ◽

Pattarica Soongsombat

Keyword(s):

Antimicrobial Activity ◽

Shelf Life ◽

Food Packaging ◽

Room Temperature ◽

Antimicrobial Properties ◽

Antibacterial Activities ◽

Heating Process ◽

Essential Information ◽

Film Forming ◽

Shrimp Wastes

Chitosan is the second most abundant polysaccharide in nature, non-toxic, biocompatible, biodegradable, and bacteriostatic and fungistatic. Many researches have devoted on the development of new biodegradable materials especially films and coatings with its polysaccharides causing film-forming properties. The heating process during plasticization has been long known for its detrimental effects on a shelf life of chitosan and possibly its antimicrobial activity. In the study, we were interested in understanding of antimicrobial activity of chitosan after mixing with various amounts of plasticizer polyethylene glycol (PEG) under various temperatures but not further be plasticized chitosan films. From fifty percentages of chitosan obtained by deacetylation of chitin which was extracted from shrimp wastes. Chitosan was mixed with plasticizer PEG, incubated at room temperature, 40, 60, 80, or 100°C for 15 min, and observed for their microbial susceptibility. The results exhibited comparable effectiveness of the antimicrobial properties in chitosan and even quite lower in chitosan blended with PEG, in exhibiting antimicrobial activity. Additionally, antibacterial activities of chitosan blended with PEG were heat dependent. These overall data will be essential information for the development of antimicrobial films and coatings in food packaging with the extending shelf life.

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Disinfection of Fruits with Activated Water

JOURNAL OF ADVANCES IN AGRICULTURE ◽

10.24297/jaa.v10i0.8462 ◽

2019 ◽

Vol 10 ◽

pp. 1864-1872

Author(s):

Prof. Teodora P. Popova

Keyword(s):

Antimicrobial Activity ◽

Aqueous Solutions ◽

Antimicrobial Properties ◽

The Other ◽

Gram Negative Bacteria ◽

High Antimicrobial Activity ◽

Gram Negative ◽

E Coli ◽

Number Of Microorganisms ◽

Lower Effect

The effect of ionized aqueous solutions (anolytes and catholyte) in the processing of fruits (cherries, morellos, and strawberries) for decontamination has been tested. Freshly prepared analytes and catholyte without the addition of salts were used, as well as stored for 7 months anolytes, prepared with 0.5% NaCl and a combination of 0.5% NaCl and 0.5% Na2CO3. The anolyte prepared with a combination of 0.5% NaCl and 0.5% Na2CO3, as well as the anolyte obtained with 0.5% NaCl, exhibit high antimicrobial activity against the surface microflora of strawberries, cherries, and sour cherries. They inactivate E. coli for 15 minutes. The other species of the fam. Enterobacteriaceae were also affected to the maximum extent, as is the total number of microorganisms, especially in cherries and sour cherries. Even stored for 7 months, they largely retain their antimicrobial properties. Anolyte and catholyte, obtained without the addition of salts, showed a lower effect on the total number of microorganisms, but had a significant effect on Gram-negative bacteria, and especially with regard to the sanitary indicative E. coli.

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Edible Films from Carrageenan/Orange Essential Oil/Trehalose—Structure, Optical Properties, and Antimicrobial Activity

Polymers ◽

10.3390/polym13030332 ◽

2021 ◽

Vol 13 (3) ◽

pp. 332

Author(s):

Jancikova Simona ◽

Dordevic Dani ◽

Sedlacek Petr ◽

Nejezchlebova Marcela ◽

Treml Jakub ◽

...

Keyword(s):

Antimicrobial Activity ◽

Essential Oil ◽

Antibacterial Properties ◽

Edible Films ◽

Attenuated Total Reflectance ◽

Practical Application ◽

Film Properties ◽

Gram Positive Bacteria ◽

Edible Packaging ◽

Orange Essential Oil

The research aim was to use orange essential oil and trehalose in a carrageenan matrix to form edible packaging. The edible packaging experimentally produced by casting from an aqueous solution were evaluated by the following analysis: UV-Vis spectrum, transparency value, transmittance, attenuated total reflectance Fourier-Transform spectroscopy (FTIR), scanning electron microscopy (SEM) and antimicrobial activity. The obtained results showed that the combination of orange essential oil with trehalose decreases the transmittance value in the UV and Vis regions (up to 0.14% ± 0.02% at 356 nm), meaning that produced films can act as a UV protector. Most produced films in the research were resistant to Gram-positive bacteria (Staphylococcus aureus subsp. aureus), though most films did not show antibacterial properties against Gram-negative bacteria and yeasts. FTIR and SEM confirmed that both the amount of carrageenan used and the combination with orange essential oil influenced the compatibility of trehalose with the film matrix. The research showed how different combinations of trehalose, orange essential oils and carrageenan can affect edible film properties. These changes represent important information for further research and the possible practical application of these edible matrices.

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Antioxidant, Antihypertensive and Antimicrobial Properties of Phenolic Compounds Obtained from Native Plants by Different Extraction Methods

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052475 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2475

Author(s):

Francisco Ramiro Boy ◽

Rocío Casquete ◽

Ana Martínez ◽

María de Guía Córdoba ◽

Santiago Ruíz-Moyano ◽

...

Keyword(s):

Antimicrobial Activity ◽

Phenolic Compounds ◽

Native Plants ◽

Antimicrobial Properties ◽

Extraction Methods ◽

Ultra Sound ◽

Antihypertensive Activity ◽

Ultrasound Extraction ◽

Rubus Ulmifolius ◽

Cistus Salviifolius

This study aims to evaluate the efficacy of two methods (agitation and ultra-sound) for extracting phenolic compounds from 15 native plants. Plant species collected in the Dehesa of Extremadura were used. The antioxidant, antihypertensive and antimicrobial activity of the phenolic extracts was investigated. Significantly different results were obtained when comparing the two extraction methods, with the highest concentrations of phenolic compounds found for ultrasound extraction. In addition, the extracts obtained for Cistus albidus, Cistus salviifolius, Rubus ulmifolius and Quercus ilex showed the highest concentrations of phenolic compounds. The antioxidant activity was higher in the extracts of Cistus and Q. ilex obtained by ultrasound, as was the antihypertensive activity. Antimicrobial activity was also higher in the extracts obtained by ultrasound from C. salviifolius and Q. ilex plants against bacteria and from Cistus ladanifer against yeasts. Therefore, it can be concluded that, with the ultrasound extraction of phenolic compounds from C. ladanifer, C. albidus and Q. ilex plants, it is possible to obtain extracts with important functional properties, so they could be studied for their use in food with the aim of obtaining healthy and safe products, favouring the sustainability of the environment of the Dehesa Extremeña.

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Phytochemical, antioxidant and antimicrobial properties of Litsea angulata extracts

F1000Research ◽

10.12688/f1000research.16620.1 ◽

2018 ◽

Vol 7 ◽

pp. 1839

Author(s):

Harlinda Kuspradini ◽

Indah Wulandari ◽

Agmi Sinta Putri ◽

Sabeti Yulis Tiya ◽

Irawan Wijaya Kusuma

Keyword(s):

Antimicrobial Activity ◽

Antioxidant Activity ◽

Radical Scavenging ◽

Antimicrobial Properties ◽

Phytochemical Analysis ◽

Dpph Radical ◽

Free Radical Formation ◽

Dpph Radical Scavenging ◽

Phytochemical Constituent ◽

Microdilution Broth

Background: Litsea angulata is a plant species belonging to Lauraceae family that is distributed throughout Indonesia, Malaysia, and New Guinea. The seeds have been traditionally used by local people in Kalimantan, Indonesia for the treatment of boils; however, there is no information about the potency of its branch, bark and leaves yet. This study aimed to determine the antioxidant, antimicrobial activity as well as the phytochemical constituent of Litsea angulata branch, bark, and leaves. Methods: Extraction was performed by successive maceration method using n-hexane, ethyl acetate, and ethanol solvent. Antioxidant activity was evaluated by DPPH radical scavenging assay. The antimicrobial activity using the 96 well-plate microdilution broth method against Staphylococcus aureus and Streptococcus mutans. Results: Based on the phytochemical analysis, it showed that extract of L. angulata contains alkaloids, flavonoids, tannins, terpenoids, and coumarin. The results showed that all extracts of plant samples displayed the ability to inhibit DPPH free radical formation and all tested microorganisms. Conclusions: L. angulata contains secondary metabolites such as alkaloids, flavonoids, tannins, terpenoids, carotenoids, and coumarin. The antioxidant activity on different plant extracts was a range as very strong to weak capacity. All extracts in this study could inhibit the growth of S. aureus and S. mutans.

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An In Vitro Study on the Antimicrobial Properties of Essential Oil Modified Resin Composite against Oral Pathogens

Materials ◽

10.3390/ma13194383 ◽

2020 ◽

Vol 13 (19) ◽

pp. 4383

Author(s):

Barbara Lapinska ◽

Aleksandra Szram ◽

Beata Zarzycka ◽

Janina Grzegorczyk ◽

Louis Hardan ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antibacterial Activity ◽

Antifungal Activity ◽

Antimicrobial Agents ◽

Resin Composite ◽

Antimicrobial Properties ◽

In Vitro Study ◽

Diffusion Method ◽

Oral Pathogens

Modifying the composition of dental restorative materials with antimicrobial agents might induce their antibacterial potential against cariogenic bacteria, e.g., S.mutans and L.acidophilus, as well as antifungal effect on C.albicans that are major oral pathogens. Essential oils (EOs) are widely known for antimicrobial activity and are successfully used in dental industry. The study aimed at evaluating antibacterial and antifungal activity of EOs and composite resin material (CR) modified with EO against oral pathogens. Ten EOs (i.e., anise, cinnamon, citronella, clove, geranium, lavender, limette, mint, rosemary thyme) were tested using agar diffusion method. Cinnamon and thyme EOs showed significantly highest antibacterial activity against S.mutans and L.acidophilus among all tested EOs. Anise and limette EOs showed no antibacterial activity against S.mutans. All tested EOs exhibited antifungal activity against C.albicans, whereas cinnamon EO showed significantly highest and limette EO significantly lowest activity. Next, 1, 2 or 5 µL of cinnamon EO was introduced into 2 g of CR and microbiologically tested. The modified CR showed higher antimicrobial activity in comparison to unmodified one. CR containing 2 µL of EO showed the best antimicrobial properties against S.mutans and C.albicans, while CR modified with 1 µL of EO showed the best antimicrobial properties against L.acidophilus.

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