Concentration Of CeO Research Articles

Active Polysaccharide-Based Films Incorporated with Essential Oils for Extending the Shelf Life of Sliced Soft Bread.

Active, fully biobased film-forming dispersions (FFDs) with highly promising results for sliced soft bread preservation were successfully elaborated from carboxymethyl cellulose (CMC) and chitosan (CH) using a simple method based on pH adjustments. They consisted of the association of polysaccharides and oleic acid (OL) added with cinnamon (CEO) or ginger (GEO) essential oils. The chemical compositions of the commercial essential oils were first determined via GC/MS, with less than 3% of compounds unidentified. The films obtained from FFDs were characterized by SEM, FTIR and DSC, indicating specific microstructures and some interactions between essential oils and the polymer matrix. CEO-based films exhibited higher antioxidant properties and a lower minimal inhibitory concentration in terms of antifungal properties. From experiments on sliced soft bread, the ginger-based films could increase the shelf life up to 20 days longer than that of the control. Even more promising, cinnamon-based films led to complete fungal inhibition in bread slices that was maintained beyond 60 days. Enumeration of the yeasts and molds for the FFD-coated breads revealed complete inhibition even after 15 days of storage with the FFDs containing the highest concentration of CEO.

Biodegradable active composite film based on pea protein isolate, sage seed gum, and cumin essential oil: Fabrication and characterization

The present study perused the physicochemical, mechanical, thermal, barrier, and optical properties of pea protein isolate (PPI)-Sage seed gum (SG) (3:1, 1:1, and 1:3) composite films incorporated with cuminum essential oil (CEO, 0, 1, and 2 %). Results indicated that the thickness, contact angle (CA), yellowness index (a*), total color differences (∆E), and opacity (OP) significantly enhanced with increasing PPI portion and CEO concentration (p < 0.05), as well as heterogeneous and inconsistent structure were increased in film surface due to protein agglomeration and oil droplets. However, the moisture content (MC), water solubility (WS), and swelling ratio (SR) decreased. Results also indicated that the antioxidant property significantly increased (P < 0.05) following the increase in CEO concentration. The highest tensile strength (TS) and elastic modulus (EM) and the least elongation at break (EAB) in PPI 3-SG 1–0 % were estimated. The potential antimicrobial property of CEO containing film was confirmed, and the maximum inhibition zone for E.coli, S.aureus, C.albicans, and A.niger were measured in film containing 2 % CEO. The barrier properties of the film against water and oxygen (WVP, OXP) diminished with increases the SG ratios, due to the hydrophilic nature of SG. The FTIR analysis identified the functional groups in film components and the interaction between film components. The DSC thermogram indicated the thermal stability of films and the highest decomposition temperature in PPI 3-SG 1–2 % film. XRD revealed a semi-crystalline structure of biopolymer active films. With the increase of SG portion and CEO concentration, the crystallinity of the films was enhanced. Results also indicated that prepared films were more than 90 % biodegradable.

Preparation and characterisation of fish skin collagen–chitosan–cinnamon essential oil composite film

SummaryThe composite film with collagen as the main component has been widely used due to its characteristics of non‐toxicity, environmental protection and health. Fish skin, a by‐product of fish, is an excellent source of collagen. Thus, collagen was extracted from an under‐utilised species, Atlantic cod (Gadus morhua) skin, and the composite film of fish skin collagen–chitosan–cinnamon essential oil was prepared by casting. The effects of the ratio of collagen to chitosan (2:8, 4:6, 5:5, 6:4, 8:2) and the concentration of essential oil (0%, 0.1%, 0.2%, 0.3%, and 0.4% (v/v)) on the composite film were studied. The structures of the composite films were analysed using scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), and X‐ray diffractometry (XRD). The collagen content of Atlantic cod skin is approximately 50.12%, which is significantly higher than that found in basa fish and Nile tilapia (P &lt; 0.05). The content of hydroxyproline was 4.51%. Analyses of tensile strength, elongation at break, water vapor permeability, and water solubility showed Co4Ch6 (Co:Ch = 4:6) had the optimal comprehensive performance, and Co4Ch6–0.2 (Co4Ch6 with 0.2% CEO) had high water resistance in the high‐humidity environment. As the CEO concentration rose, the composite films' infrared absorption bands were enhanced in amplitude, and the XRD peaks were gradually intensified, indicating the internal crystallinity and, thereby, the opacity of the composite films were improved. The bacteriostasis zones Co4Ch6–0.4 against Escherichia coli and Staphylococcus aureus were 2.02 cm and 1.73 cm, respectively. The DPPH radical scavenging rate of Co4Ch6 rose with the increase in CEO concentration, and the DPPH radical scavenging rate of C04Ch6–0.4 was up to 48.56%. Thus, the composite films prepared from fish skin collagen, chitosan, and cinnamon essential oils have outstanding mechanical properties, barrier ability, and antimicrobial activity and are promising for application in food packaging and storage. In addition, the composite films showed a potential antioxidation ability, which might be used as green bioactive films to preserve nutraceutical products.

Extending the Shelf-Life of Nectarines through Fish Gelatin/Cellulose Nanocrystals/Cinnamon Essential Oil-Based Edible Coatings

The effect of bacterial cellulose nanocrystal–fish gelatin/cinnamon essential oil (BCNCs–FGelA/CEO) nanocoatings containing different concentrations of essential oil (1.2, 1.8, and 2.4 mL/L) on reducing the ripening and aging processes of ‘Red Gold’ nectarine fruit during cold storage (60 days, 4 °C) was studied. As a general trend, the application of the coating delayed the ripening process, and increasing the concentration of essential oil was effective in improving the coating efficacy. After 60 days, the lowest values of weight loss (6.93%), peroxidase and polyphenol oxidase activity (11.49 and 0.48 abs min−1 g−1, respectively), soluble solid content (14.56%), and pH (4.17) were detected for samples covered with the BCNCs–FGelA coatings containing the highest tested CEO concentration, whereas the maximum values of the same parameters (20.68%, 18.74 and 0.76 abs min−1 g−1, 17.93%, and 4.39, respectively) were found in the uncoated samples. In addition, increasing the concentration of the essential oil resulted in a better preservation of the firmness, ascorbic acid, and total acidity of the samples. Finally, the respiration rate and ethylene production of coated samples were lower than those detected in uncoated samples, though some differences arose depending on the amount of CEO loaded in the coatings. This study showed the capability of BCNCs–FGelA/CEO coatings to increase the cold storage period and preserve the quality of ‘Red Gold’ nectarine fruit, thereby reducing losses and increasing economic efficiency in the fruit industry.

Preservation effects of chitosan/polyvinyl alcohol/clove essential oil antifungal film on yellow peaches: Physicochemical properties and fruit quality assessment

Using antifungal food packaging films presents a significant opportunity to prolong the shelf-life of food products. In this work, a chitosan-polyvinyl alcohol antibacterial film, enriched with clove essential oil (CS/PVA/CEO), was developed for preservation effects on yellow peaches, and its physical properties and structure were investigated. The good compatibility and thermal stability of CS/PVA/CEO film were demonstrated via scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. Mechanical properties are exhibited at a 0.75% CEO concentration: the tensile strength is (25.09 ± 0.32) MPa, elongation at break is (291.23 ± 2.53)%, water vapor permeability is (0.479 ± 0.005) g·mm·m−2·h−1·kPa−1, water resistance is (18.57 ± 0.35)%, and water resistance is (9.70 ± 0.26)%. During the 11 days of storage at temperatures ranging from 23 °C to 26 °C and 26 days of storage at 4 °C–5 °C, the CS/PVA/CEO film exhibited effective preservation of yellow peach fruits. CS/PVA/CEO group extended 3–4 d at room temperature and 5–10 d at 4 °C of yellow peaches preservation compared with the CS/PVA and control groups. This effectiveness was evaluated based on various parameters, including fruit appearance, decay rate, respiratory intensity, malondialdehyde concentration, firmness, total soluble solids, and titratable acidity. Therefore, adding CEO into the antifungal film demonstrated excellent potential in enhancing the preservation of yellow peaches.

Cinnamon essential oil/inulin inclusion complexes: Physicochemical, rheological, thermal, morphological, and antimicrobial properties

AbstractCinnamon essential oil (CEO), an excellent source of active antimicrobial compounds, has a strong flavor and extreme volatility, which limits its application in the food industry. The objective of this study was to encapsulate CEO into inulin (INL) by freeze‐drying at selected concentrations (10%–20% w/w). Encapsulates containing 15% CEO exhibited the maximum encapsulation efficiency (63.30%). The concentrations of CEO significantly influenced the melting of encapsulates and their melt rheology. Oscillatory rheology data displayed abnormalities in the rheograms with increasing CEO concentrations in encapsulates. X‐ray diffraction and Fourier transform infrared spectroscopy peaks demonstrated the formation of successful encapsulations. The cracks on the encapsulated surface were visualized through SEM, and a variation in topography was quantified by atomic force microscopy measurements. The INL/CEO encapsulates demonstrated antimicrobial activity against selected pathogens, namely Salmonella Typhimurium and Listeria monocytogenes. The produced encapsulates have the potential to be used as intermediary products for food, pharmaceuticals, and packaging.Practical applicationsEncapsulates effectively retain the bioactive compounds of essential oils in a complex and release them through controlled mechanisms. These encapsulates have significant industrial applications in active packaging, flavor retention, and pharmaceutics.

Effects of clove essential oil on eggshell bacterial load, antibacterial sensitivity, and hatchability

Background and objective Clove essential oil’s (CEO) physical and chemical properties allow for its potent antibacterial action. This study sought to determine the impact of various CEO disinfectant concentrations on the eggshell bacterial load, embryonic mortality, hatchability, and chick quality. Materials and methods A total of 1500 fertile chicken eggs were randomly divided into five treatment groups. Group one was sprayed with a commercial disinfectant (BioSentry 904), the second group was sprayed with ethyl alcohol 70%, and the last three groups were sprayed with 0.5, 1, or 2% of CEO. After spraying, eggs in each group were used for the determination of total bacterial load on the eggshell, hatchability, embryonic mortality, and chick quality. Results and conclusion Results showed that the bacterial load on the eggshell declined with the increase in the concentration of CEO. The use of CEO at 1, 2%, or BioSentry 904 resulted in the lowest bacterial load. However, hatchability of set and fertile eggs for the group treated with CEO at 0.5% was numerically greater than other groups, while chick quality grade (A) was numerically greater by CEO at 1% concentration. The chick yield of the egg group treated with CEO at 1% was significantly higher than in the control group. Embryonic mortalities for all groups were statistically similar. In conclusion, using CEO at different concentrations 1, 2%, or BioSentry 904 in disinfecting broiler breeder eggs can effectively reduce the bacterial load on eggshells. In addition, using CEO improved chick quality and chick yield without any adverse effect on hatchability. Consequently, it is considered a strong competitor to BioSentry 904 and a less hazardous disinfectant for hatching egg disinfection on a commercial scale.

Public support and energy innovation: Why do firms react differently?

The literature provides mixed evidence on whether the public supports foster or fail to promote innovation. This paper explores why the effects of government R&D subsidies on corporate innovation performance vary across firms. We rely on publicly listed firms in China and find that government subsidies promote technology innovations in firms specialized in either renewable energy or fossil fuel-related innovations, but fail to motivate firms with mixed directions on both types of patenting lines to innovate. This could be explained by corporate pursuit of innovation goals, and further substantiated by the heterogeneous effects of managerial features of the firms. The effectiveness of R&D subsidies is much smaller in mixed firms with finance-oriented CEO and lower concentration of shareholders, and when firms disclose corporate social responsibility. We present empirical evidence that government R&D subsidies crowd out mixed firms' private R&D expenditure and increase their non-operating expenses. Our findings warn that it is important to improve the supervision mechanism for the use of R&D subsidies in firms and learn to manage multiple objectives, especially for firms with mixed purposes.

Production of Innovative Essential Oil-Based Emulsion Coatings for Fungal Growth Control on Postharvest Fruits.

This work assessed the antimicrobial potential of natural essential oils (EOs) from cinnamon (CEO), zataria (ZEO), and satureja (SEO), applied natively or as coatings against Penicillium expansum and Botrytis cinerea during both in vitro and in vivo (on apple fruits) experiments. The induced inhibitory effect towards fungal growth, as a function of both EO type and concentration (75–1200 μL/L), was preliminarily investigated to select the most suitable EO for producing bacterial cellulose nanocrystals (BCNCs)/fish gelatin (GelA)-based emulsions. CEO and ZEO exhibited the best performances against P. expansum and B. cinerea, respectively. None of the pristine EOs completely inhibited the fungal growth and “disease severity”, properly quantified via size measurements of lesions formed on fruit surfaces. As compared to pristine CEO, coating emulsions with variable CEO concentration (75–2400 µL/L) curbed lesion spreading on apples, owing to the controlled CEO release during a 21-day temporal window. The strongest effect was displayed by BCNCs/GelA-CEO emulsions at the highest CEO concentration, upon which lesions on fruit skins were barely detectable. This work demonstrated the capability of EOs embedded in BCNCs/GelA-based nanocapsules to efficiently slow down microbial spoilage on postharvest fruits, thus offering viable opportunities for developing innovative antimicrobial packaging systems.

INVESTIGATING RELATIONSHIP BETWEEN CHANGES IN CORPORATE GOVERNANCE CHARACTERISTICS AND PROFIT QUALITY

The main purpose of this study is to investigate the relationship between changes in corporate governance characteristics of profit quality in companies listed on the Tehran Stock Exchange. In this study, changes in the characteristics of corporate governance include changes in the independence of the board of directors, CEO, auditor and concentration of ownership, and the Kothari (2005) model has been used to measure the quality of profits. The statistical population of the study includes 161 companies listed on the Tehran Stock Exchange and the period is from 2010 until 2015. The tests were performed at the general level of companies, small companies and large companies. The research findings indicate that in general, there is a negative and significant relationship between changes in corporate governance characteristics, i.e. changes in CEO, auditor and ownership concentration with profit quality at the general level of companies. But in large corporations, no relationship was found between changes in board independence and ownership concentration with profit quality. Also, there is a negative and significant relationship between the changes of the CEO and the auditor with the quality of profits at the level of large companies. In addition, no significant relationship was found between changes in corporate governance and profit quality at the level of small companies

Cinnamomum cassia and Syzygium aromaticum Essential Oils Reduce the Colonization of Salmonella Typhimurium in an In Vivo Infection Model Using Caenorhabditis elegans.

The regulation of intestinal colonization in livestock by means of non-bactericidal additives is an important management lever for zoonotic bacteria such as Salmonella spp. Caenorhabditis elegans is proposed here as a model for the evaluation of five essential oils (EOs) as anti-colonization products against Salmonella Typhimurium. An evaluation of the toxicity of EOs for C. elegans showed LD50 values ranging from 74.5 ± 9.6 µg/mL for Cinnamomum cassia (CEO) to 271.6 ± 14.9 µg/mL for Syzygium aromaticum (SyEO). Both EOs significantly inhibited bacterial colonization in the digestive tract of C. elegans with reductions of 0.88 and 0.70 log CFU/nematode at nontoxic concentrations of 50 µg/mL and 150 µg/mL, respectively. With the minimal bactericidal concentrations of CEO and SyEO against S. Typhimurium being 312.5 µg/mL and 625 µg/mL, respectively, an antibacterial effect can be excluded to explain the inhibition of the bacterial load. The anti-colonizing activity of these two EOs could, however, be related to an inhibition of the swimming motility, which was significantly reduced by 23.47% for CEO at 50 µg/mL and 19.56% for SyEO at 150 µg/mL. This study shows the potential of C. elegans as a predictive in vivo model of anti-colonizing activities that is suitable for the evaluation of essential oils.

IMPACT OF CORPORATE GOVERNANCE ON FIRM PERFORMANCE: EVIDENCE FROM PAKISTAN

The study attempts to figure out the relationship between the performance of the firms and corporate governance in Pakistan. Governance mechanisms used in this study are CEO duality, Independence of Board, Size of Board, and Ownership Concentration. While, the ROA and ROE have been used as dependent variables to measure the performance of firms. Using regression analysis technique on 10 listed firms trading over four years from 2014-2017, the results have been derived. The data regarding all the variables have been collected from all the companies’ annual reports. The discoveries of the study direct that fundamentals of corporate governance such as the Size of the Board, Ownership, and Duality Concentration of CEO have negative effects on performance of organization, as measured by ROA and ROE. While Board independence positively affects the performance of firms. The results are thus significant and provide valuable information for the decision makers about the research issues under consideration.

Evaluation of the composition and in vitro antimicrobial, antioxidant, and anti-inflammatory activities of Cilantro (Coriandrum sativum L. leaves) cultivated in Saudi Arabia (Al-Kharj).

BackgroundIn the present study, we explored the composition of Cilantro (Coriandrum sativum L. leaves) essential oil (CEO) cultivated in Saudi Arabia (Al-Kharj) and explored its antioxidant, antimicrobial, and anti-inflammatory effects in vitro.MethodsGas chromatography-mass spectroscopy was used to detect the CEO composition. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH)-induced free radical and ferric chloride scavenging methods were used to determine the antioxidant activity. Antimicrobial activity was investigated using the well diffusion method. Anti-inflammatory activity was evaluated using egg albumin and trypsin-induced inflammation methods.ResultsForty-six compounds representing 90.17% of the total aroma were identified in the CEO; the major constituents were found to be 1-decanol (17.85%), decanal (11.04%), trans-2-dodecen-1-ol (7.87%), menthone (6.71%), 2-decen-1-ol, trans- (5.44%), dodecanal (4.76%), trans-tetradec-2-enal (3.14%), sedanolide (3.02), and thymol (3.01%). DPPH-induced free radical and ferric chloride scavenging assays demonstrated low antioxidant effects of CEO, and the antioxidant activity was observed at a high CEO concentration. The antimicrobial activity of CEO was assessed against 5 microorganisms (bacteria and fungi) by using well diffusion methods; CEO was found to possess excellent antimicrobial activity against all microorganisms, except Escherichia coli. Moreover, CEO demonstrated strong anti-inflammatory activity against egg albumin- and trypsin-induced inflammation.ConclusionThe essential oil extracted from C. sativum chemotype grown in Al-Kharj region of Saudi Arabia possesses low antioxidant potential, superior antimicrobial activity, and outstanding anti-inflammatory effects.

In vitro antifungal activity of Cinnamomum zeylanicum bark and leaf essential oils against Candida albicans and Candida auris

Candida infections are a significant source of patient morbidity and mortality. Candida albicans is the most common pathogen causing Candida infections. Candida auris is a newly described pathogen that is associated with multi-drug-resistant candidiasis and candidaemia in humans. The antifungal effects of various essential oils and plant compounds have been demonstrated against human pathogenic fungi. In this study, the effect of cinnamon leaf and bark essential oils (CEOs) was determined against both C. albicans and C. auris. The disc diffusion (direct and vapour) and broth microdilution method was used to determine antifungal activity of the EOs against selected strains (C. albicans ATCC 10231, C. albicans ATCC 2091 and C. auris NCPF 8971) whilst the mode of action and haemolysin activity of the CEOs were determined using electron microscopy and light microscopy. Direct and vapour diffusion assays showed greater inhibitory activity of bark CEO in comparison with leaf CEO. The minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of bark CEO for all tested strains was below 0.03% (v/v), which was lower than the MICs of the leaf CEO (0.06–0.13%, v/v) dependent on the strain and the MFCs at 0.25% (v/v). In the morphological interference assays, damage to the cell membrane was observed and both CEOs inhibited hyphae formation. The haemolysin production assay showed that CEOs can reduce the haemolytic activity in the tested C. albicans and C. auris strains. At low concentrations, CEOs have potent antifungal and antihaemolytic activities in vitro against C. albicans and C. auris.Key points• Essential oils from Cinnamomum zeylanicum Blume bark and leaf (CBEO and CLEO) demonstrated fungicidal properties at very low concentrations.• The antifungal activity of CBEO was greater than that of CLEO consistent with other recent published literature.• The mode of action of CBEO and CLEO was damage to the membrane of C. albicans and C. auris.• Both CBEO and CLEO inhibited the formation of hyphae and reduced haemolysin production in C. albicans and C. auris.Graphical abstract

Physiological, Biochemical and Neurochemical responses of Cirrhinus mrigala upon short term exposure to Cerium oxide

The current study was performed to ascertain the biochemical and physiological impact of cerium oxide (CeO 2 ) on freshwater fish Cirrhinus mrigala , which are widely consumed. Biochemical, neurochemical and physiological modifications were evaluated and LC 50 of CeO 2 was found to be 22 ppm, observed for 24 h. Further 1/10 th of the LC 50 concentration of CeO 2 (2.2 ppm) was used for short term investigation at 96 h. The results demonstrate an increase in physiological levels of serum lactate dehydrogenase (LDH), aspartate transaminase (AST) and alanine transaminase (ALT) compared to control groups. Studies revealed variations in oxidative stress markers with a significant reduction in the serum superoxide dismutase (SOD) and catalase (CAT) activities and an increase in malondialdehyde (MDA). The study reported the increase in brain glutamate concentrations indicating possible brain tissue damage. The above analysis highlights the potential toxicological impact of CeO 2 on freshwater fish and their ecosystem.

Voluntary disclosure of individual supervisory board compensation in public family firms

In family firms, the decision to voluntarily disclose individual supervisory board compensation induces confidence in the family firm's governance system, but may also compromise a family's efforts to keep exclusive control. Drawing on socioemotional wealth (SEW) research, we investigate family influence on a firm's voluntary disclosure decisions while distinguishing between different types of firms: non-family, true family (TFF), and lone founder firms (LFF). Our findings demonstrate the complex influence of two control-enhancing factors, family CEO and high ownership concentration, on disclosure decisions.

Antibacterial PVP/cinnamon essential oil nanofibers by emulsion electrospinning

This study presents the production of antibacterial Polyvinylpyrrolidone/cinnamon essential oil (PVP/CEO) nanofibers by oil-in-water emulsion electrospinning, with solution properties such as GC-MS, conductivity, viscosity, and characterization using SEM (fiber morphology), FT-IR (chemical structure), UV-vis (release properties of CEO). In addition, the antimicrobial properties of the nanofibers are also investigated by the disc diffusion method (antimicrobial properties) using Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. According to the results, the viscosity values increase with the addition of surfactant and with increased CEO concentration, but the conductivity increases until PVP1 then has decrease tendency. As concerns the fiber properties, the average fiber diameter increased with surfactant addition and CEO concentration except for PVP4. Also, the spinnability and fiber smoothness were enhanced significantly with surfactant and CEO. FT-IR analysis results verified the existence of CEO and PVP in the structure of the nanofibers. The absorbance values increased with the CEO concentration except for PVP4. Lastly, the antimicrobial results showed that 2, 3, and 4 wt% CEO concentration values are suitable for good antibacterial properties, while there is no zone formation with 1 wt% CEO concentration of PVP nanofibers. It is another important result that the antibacterial activity increases with the size of the nanofibrous material.

In vitro activity of the cinnamon essential oil against the plant pathogen Septoria melissae desm.

Septoria leafspot caused by the mitosporic fungus Septoria melissae Desm. is the most significant disease of lemon balm (Melissa officinalis L.). The fungus frequently appears in the plantations and causes serious yield losses or decreases the quality of the drug. At present plant protection of lemon balm is inadequate due to the lack of authorised plant protection products. The essential oil of the cinnamon bark (CEO) has a strong antimicrobial activity proved by several in vitro experiments. Therefore the goal of our work was to test antifungal effect of the CEO against the pathogen Septoria melissae Desm. In vitro tests were carried out with three concentrations (0.3%, 0.1%, 0.03%) of the CEO against a Hungarian and a Polish isolate of the fungus. Inhibition of the germination of the conidia as well as the mycelial radial growth was investigated. Supplementary tests were carried out with colonies of the fungi transferred to growth media without CEO after an incubation period of 14 and 35 days on media containing CEO. Our results showed that all the applied concentrations of CEO have very strong (98.07-100%) inhibitory effect on the mycelial growth of both isolates. Germination of conidia was also blocked on each medium containing CEO. However, the effect of the CEO at 0.03% concentration was reversible. Mycelium began to grow again on media without CEO after transfer. Based on the results, further investigation of CEO as a potential plant protection product in lemon balm crops is recommended.

Application of Cinnamomum zeylanicum essential oil in vapour phase for heritage textiles disinfection

The currently applied disinfection methods of heritage textiles tend to destroy the objects, thus the need arises to find novel, effective and safe approach. The aim of this study was to evaluate the antimicrobial effectiveness of CEO in vapour phase to disinfect new and heritage textiles, and its impact on the optical, mechanical and structural properties of materials. Minimal inhibitory concentrations of CEO in vapour phase were estimated as 5.625 μg ml−1 for moulds (Aspergillus niger, Penicillium funiculosum, Trichoderma viride), and 22.5 μg ml−1 for bacteria (Streptomyces rutgersensis, Bacillus megaterium, Pseudomonas fluorescens). Depending on the species tested, the number of viable microorganisms on textiles was reduced by 2 – 7 logarithmic units after CEO disinfection. No significant changes in the optical, mechanical and structural parameters of the textiles were observed after CEO disinfection. In this context, disinfection with CEO in vapour phase seems to be an effective, sustainable and safe method of heritage textiles disinfection.

Description of Aspergillus flavus growth under the influence of different factors (water activity, incubation temperature, protein and fat concentration, pH, and cinnamon essential oil concentration) by kinetic, probability of growth, and time-to-detection models

A Box-Behnken design was used to determine the effect of protein concentration (0, 5, or 10g of casein/100g), fat (0, 3, or 6g of corn oil/100g), aw (0.900, 0.945, or 0.990), pH (3.5, 5.0, or 6.5), concentration of cinnamon essential oil (CEO, 0, 200, or 400μL/kg) and incubation temperature (15, 25, or 35°C) on the growth of Aspergillus flavus during 50days of incubation. Mold response under the evaluated conditions was modeled by the modified Gompertz equation, logistic regression, and time-to-detection model. The obtained polynomial regression models allow the significant coefficients (p<0.05) for linear, quadratic and interaction effects for the Gompertz equation's parameters to be identified, which adequately described (R2>0.967) the studied mold responses. After 50days of incubation, every tested model system was classified according to the observed response as 1 (growth) or 0 (no growth), then a binary logistic regression was utilized to model A. flavus growth interface, allowing to predict the probability of mold growth under selected combinations of tested factors. The time-to-detection model was utilized to estimate the time at which A. flavus visible growth begins. Water activity, temperature, and CEO concentration were the most important factors affecting fungal growth. It was observed that there is a range of possible combinations that may induce growth, such that incubation conditions and the amount of essential oil necessary for fungal growth inhibition strongly depend on protein and fat concentrations as well as on the pH of studied model systems. The probabilistic model and the time-to-detection models constitute another option to determine appropriate storage/processing conditions and accurately predict the probability and/or the time at which A. flavus growth occurs.