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Thyme essential oil (TEO) is a natural food antimicrobial agent derived of spice, but suffers from volatility and poor water solubility, which problem can be effectively solved by the encapsulation of liposomes. On this basis, a safe and common natural antibacterial protein, LYZ was used to modify the TEO liposomes (TEO-lips) for gaining better properties. 2.5 mg/mL TEO and 0.05 % LYZ/S100 mass ratio were the best formula for the preparation of LYZ-TEO-lips. After LYZ modification, the particle size and PDI increased, and the zeta potential decreased slightly. The modification of LYZ not only improves the thermal stability of TEO-Lips, weakens the influence of acid and salt ions on liposomes, but also improves the antibacterial properties of TEO-Lips. In brief, LYZ has the potential to improve the overall properties of liposomes and can provide a reference for the development of antimicrobial liposomes.

Background: Combination antifungal therapy has become a prominent approach in medical practice as it takes advantage of synergistic interactions by interfering with multiple targets of the pathogen, broadening the spectrum of activity, reducing the development of resistance, and improving treatment outcomes. Therefore, combining conventional antifungal drugs with natural products can increase antifungal activity, reduce side effects, and optimize therapeutic effects. Purpose: The present study aimed to evaluate the antifungal activity of thyme essential oil (ThyEO) in combination with amphotericin B, caspofungin, fluconazole, itraconazole, and posaconazole (PSZ), as well as its inhibitory effect on Candida albicans virulence factors. Materials and Methods: The microbroth dilution assay was employed to determine the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). Interactions were assessed using the microdilution checkerboard assay. Ergosterol and methylene blue assays were used to detect effects on fungal membrane, while the sorbitol assay was used to detect effects on fungal cell wall. Inhibition of yeast virulence factors (adherence to epithelial cells, germ tube and pseudomycelium formation, secretion of hydrolytic enzymes, and biofilm formation) was assessed with previously reported methods. Results: Almost all combinations showed additivism against C. albicans, except ThyEO/PSZ (31.25/0.0039 µg/ml), which showed partial synergism. Furthermore, all mixtures were fungicidal against C. albicans strains. ThyEO/PSZ, its components alone, and thymol were shown to disrupt the fungal cytoplasmic membrane, increasing its permeability. ThyEO/PSZ, at sub-inhibitory concentrations, significantly decreased the ability of C. albicans to adhere to buccal epithelial cells. ThyEO/PSZ, ThyEO, and PSZ were able to reduce the pseudomycelium production of C. albicans while thymol completely inhibited its formation. ThyEO/PSZ, each combination component on its own, and thymol inhibited biofilm formation and preformed biofilm of C. albicans. Notably, ThyEO/PSZ showed synergistic and fungicidal activity against a resistant strain of C. albicans, reducing the PSZ dose by 4-fold. Conclusion: These findings make ThyEO and ThyEO/PSZ mixture valuable candidates for the development of alternative antifungals with a lower incidence of adverse effects.

A chicken protein hydrogel (HG) was enzymatically prepared and blended with a carnauba wax-based oleogel (OG) to form bigels (BG) in ratios of 50:50 to 90:10. These systems were infused with thyme essential oil (TEO) at 0.5 %, 1 %, and 2 % v/v to harness its antioxidant properties. Polarized light microscopy revealed that carnauba wax crystals were tightly arranged in thin, plate-like structures, while the HG exhibited a completely amorphous form. FT-IR analysis indicated that OH bonds in the HG and CH bonds in cycloalkanes from the OG contributed to the stability and strength of the gels. Unlike the biphasic gels, both the OG and HG samples experienced structural disintegration when the applied strain reached approximately 30 %. HG samples, with an onset melting temperature of 59.18 °C, were particularly susceptible to thermal deformation, leading to coalescence and destabilization of the BG due to the HG phase in the composite matrix. Regardless of the TEO concentrations, the BG (50:50) demonstrated the highest water-holding capacity (60.83 %), and oil-binding capacity (99.23 %) compared to the single biopolymer gels. The lightness of the BG increased as the HG ratio increased. Additionally, the antioxidant capacity increased with higher TEO concentrations, demonstrating the gels' potential for food applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Since foodborne diseases are often considered as one of the biggest public health threats worldwide, effective preservation strategies are needed to inhibit the growth of undesirable microorganisms in food commodities. Up to now, several techniques have been adopted for the production of safe and high-quality products. Although the traditional methods can improve the reliability, safety, and shelf-life of food, some of them cannot be applied without rising health concerns. Thereby, the addition of various phytochemicals has gained much attention during the last decades, especially for meat products that may be contaminated with pathogenic and spoilage organisms.Thyme (Thymus vulgaris L.), as an important medicinal and culinary herb, is a promising source of bioactive compounds that have a great impact on the microbiological stability of meat by suppressing the undesirable microflora. However, the use of these antimicrobials is still facing difficulties due to their aromatic properties and variable efficacy against targeted species.In this paper, we provide an overview on the potential effects of thyme essential oil (EO) and thymol as bio-preservative agents in meat products. Furthermore, this paper provides insights into the limitations and current challenges of the addition of EOs and their constituents to meat commodities and suggests viable solutions that can improve the applicability of these phytochemicals.

The present study was evaluated and fabricated the thyme essential oil (TEO) nanoemulsion form to use in preservative of UF labneh. The antimicrobial and chemical composition of the oil was determined by well diffusion method and Gas chromatography–mass spectroscopy (GC–MS). The TEO nanoemulsion was characterized by Dynamic light scattering (DLS), Transmission electron microscope (SEM), and time killer effect. Inclusion TEO exhibited high inhibitory effects against numerous pathogenic strains, in which the diameter of inhibition ranged from 10 to 36 according to different concentrations of TEO. The GC–MS analysis of TEO has detected 15 compounds mainly thymol (43.63%). TEO nanoemulsion was almost spherical with a diameter of 52 nm and able to eliminate pathogenic counts within 60 min. The fortified labneh with different concentrations (0.1, 0.2, and 0.3%) TEO nanoemulsion was kept the quality of labneh up to six weeks. The counts of psychrotrophic, mold, and yeasts were indicated in the eighth week compared with control. The addition of TEO nanoemulsion was affected slightly on chemical properties during storage. Therefore, the highest total scores were given to labneh with 0.1% TEO nanoemulsion. The results suggested that the formulated TEO nanoemulsions might be a promising agent to prolong the shelf life and enhanced the aroma of labneh.

This study developed a multifunctional paper-based freshness antibacterial indicator card by dual-sided coating on conventional filter paper. The indicator coating was composed of anthocyanins from purple cabbage, and polyvinyl alcohol and sodium carboxymethyl cellulose as substrates while the antibacterial coating contained halloysite nanotubes for loaded thyme essential oil and chitosan. FT-IR, XRD, and SEM analyses revealed that the components were well-mixed, and the paper was tightly bound to the coatings through hydrogen bonds. Additionally, the coating effectively filled the porous fiber gaps in the paper, significantly enhancing the mechanical properties of the paper. The tensile strength of the coated paper was enhanced from 14.28 MPa to a range of 42.25-47.71 MPa, and the bending resistance was increased from 0.35 N·mm to a range of 1.72-1.99 N·mm compared to the uncoated paper. The addition of anthocyanins provided excellent sensitivity to pH and ammonia for the indicator card. Furthermore, the coating including halloysite nanotubes for loaded thyme essential oil exhibited antimicrobial resistance against Escherichia coli and Staphylococcus aureus. When used on fresh carp, the antibacterial indicator card not only indicated the freshness of the carp but also extended the best before date of the fish meat by 1-2 days. The indicator exhibited the most pronounced color transformation and optimal freshness indication performance when the mass fraction of anthocyanins was 2 %., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. This work is original research and the data presented in the manuscript has not been published elsewhere., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The aim of this study was to develop novel konjac glucomannan (KGM)-based highly antibacterial active films, where five types of films were prepared and compared. The microstructure results showed that KGM-based films loaded with thyme essential oil (TEO) through bacterial cellulose nanofibers/Ag nanoparticles (BCNs/Ag nanoparticles) stabilized Pickering emulsions (Type V films) displayed the smoothest surface and the most evenly dispersed TEO droplets as compared with the other four types of films. Moreover, Type V films showed the highest contact angle value (86.28°), the best thermal stability and mechanical properties. Furthermore, Type V films presented the highest total phenol content (13.23 mg gallic acid equivalent/g film) and the best antioxidant activity (33.96 %) as well as the best sustained-release property, thus showing the best antibacterial activity, which was probably due to that BCNs/Ag nanoparticles and TEO displayed a synergistic effect to some extent. Consequently, Type V film-forming solutions were used as coatings for tangerines. The results showed that the tangerines treated with Type V coatings displayed excellent fresh-keeping properties. Therefore, the coatings, KGM-based film-forming solutions loaded with TEO through BCNs/Ag nanoparticles stabilized Pickering emulsions, have great potential for the preservation of fruits and vegetables., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled, “Konjac glucomannan-based highly antibacterial active films loaded with thyme essential oil through bacterial cellulose nanofibers/Ag nanoparticles stabilized Pickering emulsions”., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The antioxidant and antimicrobial properties of thyme essential oil (TEO) are useful for active food packaging, but its poor aqueous solubility restricts its applications. This work involves anionic cellulose nanofibers (CNFs) as the sole stabilizing agent for TEO-in-water emulsions, with oil concentrations ranging from 10 mL/L to 300 mL/L. A double mechanism was proposed: the adsorption of CNFs at oil/water interfaces restricted coalescence to a limited extent, while thickening (rheological stabilization) was required to avoid the buoyance of large droplets (>10 μm). Thickening effects comprised both higher viscosity (over 0.1 Pa·s at 10 s -1 ) and yield stress (approximately 0.9 Pa). Dilute emulsions had good film-forming capabilities, whereas concentrated emulsions were suitable for paper coating. Regarding antimicrobial activity, CNF-stabilized TEO-in-water emulsions successfully inhibited the growth of both Gram-negative (E. coli, S. typhimurium) and Gram-positive bacteria (L. monocytogenes). As for the antioxidant properties, approximately 50 mg of paper or 3-5 mg of film per mL of food simulant D1 were required to attain 50 % inhibition in radical scavenging tests. Nonetheless, despite the stability and the active properties of these bio-based hydrocolloids, providing this antioxidant and antimicrobial activity was incompatible with maintaining the organoleptic properties of the foodstuff unaltered., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Developing safe, eco-friendly, and functionally edible packaging materials has attracted global attention. Essential oils, can be incorporated into packaging materials as antioxidant and antibacterial agents. However, their high volatility and discontinuous film matrix issues may cause a rough film surface, limiting the application in food packaging. In this study, thyme essential oil microemulsion (TEO-M) was prepared and incorporated into a pullulan-sodium alginate (PS) film. The TEO-M incorporation endowed the PS film with antioxidant and UV protection properties. The antioxidant activities of the TEO-M-incorporated PS film were significantly better than those of the TEO-C (thyme essential oil coarse emulsion)-incorporated PS film. In comparison to TEO-C, the distribution of TEO-M in the film is more uniform. Lipid oxidation and the growth of microorganisms in chilled pork were inhibited by incorporating TEO-M at a concentration of 50 mg/mL in the PS film (PS-50M). After 10 days of storage at 4 °C, the total viable count (TVC) of chilled pork preserved in the PS-50M material was significantly reduced compared to the control group (P < 0.05). This study shows that incorporating TEO-M in the PS film provides a method for applying essential oils in food packaging, which may have great potential in the food industry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. All the authors listed have approved the manuscript and have no conflict about the signature order., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this study, thyme essential oil (TEO) nanoemulsion was immobilized within composite films based on almond gum (AG), polyvinyl alcohol (PVA), and chitosan (CS). The physical, mechanical, water barrier, microstructural and antimicrobial properties of composite films were assessed. Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis confirmed the intermolecular interactions in the composite film matrix. The results indicated that the incorporation of TEO into the composite films increased thickness, moisture content, and water vapor permeability, while it reduced light transmittance and transparency value. The antimicrobial activity of films against gram-negative and gram-positive bacteria was tested using a disc diffusion method. The effect of composite on the microbiological properties of chicken breast fillets was investigated during refrigerated storage for 21 days. The microbial populations of total mesophilic, psychrotrophic, and lactic acid bacteria of the samples that were coated with the composite containing TEO were lower than the permitted limit after 21 days while for blank samples they were higher than 7 log CFU/g after 7 days which is considered as the maximum acceptable total count limit. Results disclosed that AG/PVA/CS composite films containing TEO nanoemulsion can be applied as eco-friendly active food packaging to enhance the shelf-life of food products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

This study aims to optimize the preparation of thyme essential oil nanoemulsion using a ternary mixture design based on the following three components: chitosan, gum Arabic and median-chain triacyglycerols (MCT). The results showed that the formulation which contained 40% chitosan, 40% gum Arabicand 20% of MCT led to a stable nanoemulsion within 30 days of storage at 4 °C. Indeed, the observed mean diameter (d [4,3] ) and the polydispersity index (PDI) are the lowest with a ζ-potential value greater than +30 mV. Moreover, the amount of thyme essential oil dissolved in MCT was optimized and the 2% (w/w) was selected to prepare O/W nanoemulsion for preserving meat products. Besides, the obtained data of the chemical characteristics of meat products demonstrated that the pH, TVNB, TBARS, shear strength increased slightly and insignificantly with storage time at 4 °C.However, there was a difference between control and sample treated with nanoemulsionsin terms of physicochemical characteristics., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This study aimed to develop potato starch nanocomposite films containing mesoporous nano-silica (SBA-15, SBA-16 and MCM-41) incorporated with Thyme essential oil (TEO). TEO-SBA-15/potato starch films, TEO-SBA-16/potato starch films and TEO-MCM-41/potato starch films were prepared based on potato starch. The physical and mechanical properties of the nanocomposite films were also investigated. The results showed that the addition of mesoporous nano-silica incorporated with TEO improved the properties of potato starch nanocomposite films. Especially, the addition of TEO-MCM-41 markedly enhanced the tensile strength (4.33 MPa), and reduced the water vapor permeability (1.80 g·m -1 ·h -1 ·KPa -1 ) and moisture absorption (37.67%) of potato starch nanocomposite films. The results of scanning electron microscopy (SEM) analysis showed that TEO-MCM-41 hardly agglomerated in the potato starch nanocomposite films. Additionally, Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) confirmed that strong hydrogen bonds were formed between TEO-MCM-41 and potato starch. The release kinetics of TEO proved that incorporating TEO into the pores of mesoporous nano-silica could delay its release rate, and the Peleg model (t/(M t  - M 0 ) = K 1  + K 2 t) was suitable for describing the release behavior. The findings of this study suggested that TEO-MCM-41/potato starch films had a good application prospect in the field of slow-releasing and antimicrobial packaging materials., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Herein, we entrapped Thymus vulgaris essential oil (EO) within the physically cross-linked sponge-like architecture of cryogels by ice template-assisted freeze-drying. Their 3D cryogenically-structured network was built through hydrogen bonding formed by blending two naturally-derived polysaccharides, chitosan and dextrin. The embedment of EOs within the cryogel matrix generates porous films with an increased elasticity that allows their fast shape recovery after full compression. Thus, the swollen EOs-loaded cryogel films exhibited an elastic modulus of 3.00 MPa, which is more than 40 times higher than that of polysaccharide films without EOs (an elastic modulus of only 0.07 MPa). In addition, the encapsulation of bioactive compounds endows the bio-based films with both antioxidant and antifungal properties, showing a radical scavenging activity of 65% and a zone inhibition diameter of 40 mm for Candida parapsilosis fungi. Our results recommend the entrapment of EOs into bio-based cryogel carriers as a straightforward approach to provide 'green' polysaccharide-based films having both improved physicochemical properties and remarkable antifungal activity., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The effect of chitosan (C), chitosan enriched with thyme (CT) or rosemary (CR) essential oils, and potassium sorbate (PS) against superficial fungal growth was investigated in fermented sausages during 3 months of storage at 4 °C. For control groups, distilled water (DW) and acetic acid (AA) were used. PS, C, CT and CR treatments inhibited fungal growth on casings while they resulted in lower Gram(+) catalase(+) cocci, Enterobacteriaceae, mold and yeast counts in sausages. Lower TBARS values were determined for CT and CR (p < .05). A total of 44 and 64 volatile compounds were identified in sausages and casings, respectively. Sausages coated with C, CT or CR had acceptable sensory attributes at the end of storage; however, DW and AA groups were rejected in the second and third month (p < .05), respectively, due to intense fungal growth which resulted in sensory defects., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The aims of this study were (i) screening of antifungal activity of thyme essential oil on Penicillium paneum; (ii) development of growth/no-growth models (G/NG); and (iii) validation of the G/NG models by performing bread baking trials. The screening method was based on the measurement of fungal growth in a semi-solid medium through optical density. The combined influence of a w (0.88-0.97), pH (4.8-7.0), temperature (22 and 30 °C), time (0-144 h) and varying concentrations of thyme oil (0-2 μL/mL YES) were assessed. Growth of P. paneum at a w 0.88 was significantly reduced compared to a w 0.93-0.97. A slight pH effect was observed at a w 0.93; growth was delayed at pH 6 compared to pH 4.8. The lowest concentration of thyme oil preventing growth during 144 h of incubation was 1 μL/mL medium. According to the results of the shelf-life test of par-baked bread, fungal growth was inhibited for more than 45 days using 0.3 mL thyme oil/100 g dough. To conclude, this study recognized the potential of using G/NG models to develop better product formulations and to facilitate product innovation., (Copyright © 2019 Elsevier Ltd. All rights reserved.)