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Dehydrated bacterial cellulose’s (BC) intrinsic rigidity constrains applicability across textiles, leather, health care and other sectors. This study aims to yield a novel BC modification method using glycerol and succinic acid with catalyst and heat, applied via an industrially scalable padding method to tackle BC’s stiffness drawbacks and enhance BC properties.

Fabric-like BC is generated via mechanical dehydration and then finished by using padding method with glycerol, succinic acid, catalyst and heat. Comprehensive material characterizations, including international testing standards for stiffness, bending properties (cantilever method), tensile properties, moisture vapor transmission rate, moisture content and regain, washing, thermal gravimetric analysis, derivative thermogravimetry, Fourier-transform infrared spectroscopy and colorimetric measurement, are used.

The combination of BC/glycerol/succinic acid dramatically enhanced porous structure, elongation (27.40 ± 6.39%), flexibility (flexural rigidity of 21.46 ± 4.01 µN m; bending modulus of 97.45 ± 18.20 MPa) and moisture management (moisture vapor transmission rate of 961.07 ± 86.16 g/m²/24 h; moisture content of 27.43 ± 2.50%; and moisture regain of 37.94 ± 4.73%). This softening process modified the thermal stability of BC. Besides, this study alleviated the drawbacks for washing (five cycles) of BC and glycerol caused by the ineffective affinity between glycerol and cellulose by adding succinic acid with catalyst and heat.

The study yields an effective padding process for BC softening and a unique modified BC to contribute added value to textile and leather industries as a sustainable alternative to existing materials and a premise for future research on BC functionalization by using doable technologies in mass production as padding.

Gallic acid is a substance that is widely found in nature. Initially, it was only used as a corrosion inhibitor to retard the rate of corrosion of metals. In recent years, with intensive research by scholars, the modification of coatings containing gallic acid has become a hot topic in the field of metal protection. This study aims to summarize the various preparation methods of gallic acid and its research progress in corrosion inhibitors and coatings, as well as related studies using quantum chemical methods to assess the predicted corrosion inhibition effects and to systematically describe the prospects and current status of gallic acid applications in the field of metal corrosion inhibition and protection.

First, the various methods of preparation of gallic acid in industry are understood. Second, the corrosion inhibition principles and research progress of gallic acid as a metal corrosion inhibitor are presented. Then, the corrosion inhibition principles and research progress of gallic acid involved in the synthesis and modification of various rust conversion coatings, nano-coatings and organic resin coatings are described. After that, studies related to the evaluation and prediction of gallic acid corrosion inhibition on metals by quantum chemical methods are presented. Finally, new research ideas on gallic acid in the field of corrosion inhibition and protection of metals are summarized.

Gallic acid can be used as a corrosion inhibitor or coating in metal protection.

There is a lack of research on the synergistic improvement of gallic acid and other substances.

The specific application of gallic acid in the field of metal protection was summarized, and the future research focus was put forward.

To the best of the authors’ knowledge, this paper systematically expounds on the research progress of gallic acid in the field of metal protection for the first time and provides new ideas and directions for future research.

Gamma-aminobutyric acid (GABA) is a four-carbon and nonprotein amino acid, made by various microorganisms, especially lactic acid bacteria (LAB) and probiotics. GABA has various physiological roles, for instance, insomnia, depression, hypotensive activity as well as diuretic effects. The production of GABA-based foods is a favorable result from GABA’s biological and functional properties. The purpose of this study is to investigate different methods of improving GABA production in probiotics and LAB to select the superlative method and bacterial strain.

In this review paper, all articles from five electronic databases containing Google Scholar, Web of Science, PubMed, Scopus and Science Direct were considered from 2000 to January 11, 2023, with keywords “Optimization” OR “Enhance” OR “Increase” AND “Gamma-aminobutyric acid” OR “GABA” AND “Probiotics” OR “Lactic acid bacteria” and selected according to the purpose of the study.

It seems that among all the investigated methods, an effective fermentation procedure with optimal conditions including fermentation medium, 5 L; glutamic acid, 295 g/L; incubation temperature, 32°C; inoculum, 10% (v/v); and agitation, 100 rpm, after 48 h of fermentation led to producing 205,800 mg/L of GABA from the effective bacterial strain Lactobacillus brevis NCL912.

With a simple but optimized fermentation, L. brevis NCL912 can be used for the efficient GABA production in the pharmacy and food factories.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

The main aim of this study is to characterise and identify specific chemo-sensory profiles of ciders from the Canary Islands (Spain).

Commercial samples of Canary ciders were compared to ciders from the Basque Country and Asturias. In total, 18 samples were studied, six for each region. The analysis comprised their sensory profiling and chemical characterisation of their polyphenolic profile, volatile composition, conventional chemical parameters and CIELAB colour coordinates. In parallel, the sensory profile of the samples from the Canary Islands was first compared with their Basque and Asturian counterparts by labelled sorting task. Then, their specific aroma profile was characterised by flash profile. Further quantification of sensory-active compounds was performed by GC–MS and GC-FID to identify the volatile compounds involved in their aroma profile.

Results show that Canary ciders present a specific chemical profile characterised by higher levels of ethanol, and hydroxycinnamic acids, mainly t-ferulic, t-coumaric and neochologenic acids, and lower levels of volatile and total acidity than their Asturian and Basque counterparts. They also present a specific aroma profile characterised by fruity aroma, mainly fruit in syrup and confectionary, and sweet flavours related to their highest levels of vinylphenols formed by transformation of hydroxycinnamic acids.

An integrated strategy to explore the typicity of the currently existing Canary ciders in the market was developed. The results are important in that they will help other regions to identify specific typical chemo-sensory profiles and to promote the creation of certifications supporting regional typicity.

This paper aims to study the color change kinetics of lac dye in response to pH and food spoilage metabolites (ammonia, lactic acid and tyramine) for its potential application in intelligent food packaging.

UV-Vis spectroscopy was used to study the color change of dye solution. Ratio of absorbance of dye solution at 528 nm (peak of ionized form) to absorbance at 488 nm (peak of unionized form) was used to study the color change. Color change kinetics was studied in terms of change in absorbance ratio (A528/A488) with time using zero- and first-order reaction kinetics. An indicator was prepared by incorporating lac dye in agarose membrane to validate the result of study for monitoring quality of raw milk.

Dye was orange-red in acidic medium (pH: 2 to 5) and exhibited absorbance peak at 488 nm. It turned purple in alkaline medium (pH: 7 to10) and exhibited absorbance peak at 528 nm. The change in absorbance ratio with pH followed zero-order model. Acid dissociation constant (pKa) of dye was found to be 6.3. Color change of dye in response to ammonia and tyramine followed zero-order reaction kinetics, whereas for lactic acid, the first-order model was found best. In the validation part, the color of the indicator label changed from purple to orange-red when the milk gets spoiled.

The study opens a new application area for lac dye. The results suggest that lac dye has potential to be used as an indicator in intelligent food packaging for detection of spoilage in seafood, meat, poultry and milk.

This study aims to comparatively reveal the physical, thermal and mechanical properties of horse tail and mane hairs, which have the potential to be used in many areas.

Physical properties of horsehairs such as diameter, density, moisture and water absorption were measured. Fourier transform infrared, field emission scanning electron microscopy and amino acid analyzes were applied to the hairs. Thermal stability of horsehair was investigated by thermogravimetric analysis and differential scanning calorimetry analysis. In addition, breaking strength and elongation values of mane and tail hairs were measured.

As a result of morphological analysis of horsehair, it was observed that there are usually gaps in the internal structure of horsehair, but the size and continuity of these gaps vary. It has been determined that there is a significant difference between the tenacity values of tail and mane hairs as well as geometric characteristics. In addition, amino acid analysis has shown that the amino acid contents of horse tail and mane hairs are similar and not much different from sheep’s wool.

Horsehair has been used for various purposes such as clothing, accessories, brushes, upholstery and reinforcement material. To use horsehair in accordance with its application area and performance characteristics, it is necessary to know its physical, thermal and mechanical properties. It is considerable to reveal the similar and different aspects of tail and mane hairs to determine whether they are alternatives to each other. Therefore, revealing the characteristics of tail and mane hairs comparatively constitutes the originality of this study.

The purpose of this paper is to provide an overview of the antimicrobial and antioxidant properties of postbiotics and the use of postbiotics to increase the shelf life and quality of food.

In this review paper, all articles from five electronic databases containing Google Scholar, Web of Science, PubMed, Scopus and Science Direct were considered and selected according to the purpose of the study.

In addition to improving food safety and increasing its shelf life, natural food preservation using biological preservatives also has a positive effect on improving consumer health. As a result, protection using natural antioxidants and antimicrobial agents seems essential. Postbiotics, having favorable characteristics such as nontoxicity, long shelf life and ease of standardization and transportation, are known as suitable antioxidant and antimicrobial, and there is an interest in making antioxidant and antimicrobial active films containing postbiotics to delay spoilage, increase the shelf life of perishable foods without changing their sensory characteristics.

Postbiotic refers to all soluble factors that are either secreted from living probiotic cells or released after cell lysis. These compounds include enzymes, peptides, polysaccharides, organic acids, teichoic acids and cell surface proteins, and their effects have been proven to improve some human and animal diseases. Probiotic bacteria must survive unfavorable conditions such as processing, storage, distribution, preparation and the digestive system to exert their health-giving effects, whereas their metabolites (postbiotics) have overcome these adverse conditions well and may be a good substitute for probiotics.

This paper aims to prepare new modified alkyd resins and use it as an antimicrobial binder for surface coating applications.

Various modified alkyd resins were prepared by partial replacement of 3,6-dichloro benzo[b]thiophene-2-carbonyl bis-(2-hydroxy ethyl)-amide as a source of polyol with glycerol and confirmed by acid value, FT-IR, 1H-NMR. The modified alkyd resins were covering a wide range of oil lengths and hydroxyl content (0%, 10%, 20% and 30% excess-OH). The antimicrobial activity of the prepared alkyds was also investigated. The coatings of 60 ± 5 µm thickness were applied to the surface of glass panels and mild steel strips by means of a brush. Physico-mechanical tests, chemical resistance and antimicrobial activities were investigated.

The obtained results illustrate that the introduction of benzo[b]thiophene derivative as a modifier polyol within the resin structure improved the film performance and enhanced the physico-mechanical characteristics, chemical resistance and the antimicrobial activities.

The modified alkyd resins can be employed as antimicrobial binders in paint compositions for a variety of surfaces, particularly those that are susceptible to a high number of bacteria.

Modified alkyd resins based on antimicrobial heterocyclic compounds have the potential to be promising in the manufacturing of antimicrobial coatings and development of paints, allowing them to function to prevent the spread of microbial infection, which is exactly what the world requires at this time. Also, they can be applied in different substrates for industrial applications.

This study aims to focus on how reactive diluents with mono- and di-functionalities affect the properties of resin formulation developed from bioderived precursors. A hydroxyethyl methacrylate (HEMA) terminated urethane acrylate oligomer was synthesized and characterized to study its application in stereolithography 3D printing with different ratios of isobornyl acrylate and hexanediol diacrylate.

Polyester polyol was synthesized from suberic acid and butanediol. Additionally, isophorone diisocyanate, polyester polyol and HEMA were used to create urethane acrylate oligomer. Fourier transform infrared spectroscopy and ¹H NMR were used to characterize the polyester polyol and oligomer. Various formulations were created by combining oligomer with reactive diluents in concentrations ranging from 0% to 30% by weight and curing with ultraviolet (UV) radiation. The cured coatings and 3D printed specimens were then evaluated for their properties.

The findings revealed an improvement in thermal stability, contact angle value, tensile strength and surface properties of the product which indicated its suitability for use as a 3D printing material.

This study discusses how oligomers that have been cured by UV radiation with mono- and difunctional reactive diluents give excellent coating characteristics and demonstrate suitability and stability for 3D printing applications.