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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.

In the denim industry, enzyme washing and its combination with stone washing are generally used to get the desired worn-out look. However, these conventional methods include high water, energy and time consumption. Nowadays, laser fading, which is a computer-controlled, dry, ecological finishing method, is preferred in the denim fading process. The purpose of this study is to observe the effects of chemical pretreatment applications on laser-faded denim fabric in terms of color and mechanical properties. To eliminate the enzyme washing process in denim fading and to minimize the disadvantages of laser fading, such as decreased mechanical properties and increased fabric yellowness, various chemical pretreatment applications were applied to the denim fabric before laser fading, followed by simple rinsing instead of enzyme washing.

Two different indigo-dyed, organic cotton denim fabrics with different unit weights were exposed to pretreatment processes and then laser treatment, followed by simple rinsing. Polysilicic acid, boric acid, borax and bicarbonate were used for pretreatment processes, and laser treatment was carried out under optimized laser parameters (40 dpi resolution and 300 µs pixel time). Tensile strength was tested, and color values (CIE L*, a*, b*, ΔE*, C* and h), color yield (K/S), yellowness and whiteness indexes were measured to identify the color differences.

Before laser fading, 30 g/L and 40 g/L polysilicic acid pretreatments for sulfur-indigo-dyed fabric and a mixture of 10 g/L boric acid and 10 g/L borax pretreatments for the fabric only indigo-dyed were recommended for the laser fading with sufficient mechanical properties and good color values.

With the chemical pretreatments defined in this study, it was possible to reduce yellowness and maintain the mechanical properties after laser fading, thus minimizing the disadvantages of laser treatment and also eliminating enzyme washing.

The performance of different pretreatment‐primer systems for hot‐dip galvanized (HDG) and Galfan coated steel has been studied. The materials were pretreated with three pretreatment processes; an alkaline oxide pretreatment with either a chromate or a zirconium based post‐rinse, and a zinc phosphating pretreatment. After the pretreatment, the panels were coated with four commercially available primers. The chemically treated substrates were characterized by using ESCA and GD‐OES, and the cured paint films by using FTIR. Paint adhesion of primed panels was determined with a combined cross‐cut and impact test and also with the NMP test. Formability of the panels was tested by T‐bend test and corrosion resistance with a cyclic prohesion test. According to the prohesion test results, primed Galfan coated panels have better edge corrosion resistance than primed HDG panels. Test results also show that the effect of pre‐treatment is not as significant for the corrosion resistance as the effect of primer. However, in the case of zinc phosphated samples, excellent synergistics between the pretreatment and two of the primers was detected.

Modern thermal and non-thermal pretreatment techniques, namely, enzymatic treatment, gas phase plasma treatment and ohmic heating have become more pronounced over conventional techniques for enhanced coloured phytochemicals (pigments) extraction. Presently, numbers of pretreatment techniques are available with some unique feature. It is difficult to choose best pretreatment method to be employed for phytochemicals extraction from different sources. Therefore, this paper aims to discuss different modern pretreatment techniques for extraction with their potential results over conventional techniques.

Research and review articles targeting to the thermal and non-thermal pretreatment techniques were collected from Google Scholar. The required information has been tabulated and discussed which included qualities of modern pretreatment techniques over conventional techniques, phytochemical extraction and best pretreatment methods for optimized results.

Every pre-treatment has its own advantages and disadvantages for a particular phytochemical and its extraction from various sources. Enzymes can be used in combinations to enhance final yield like extraction of carotenoids (pectinase, cellulase and hemicellulase) from chillies and lycopene (pectinase and cellulase) from tomato. Utilization of each method depends upon many factors such as source of pigment, cost and energy consumption. CO₂ pretreatment gives good results for carotenoid extraction from algae sources. Ohmic heating can yield high anthocyanin content. Modifications in conventional blanching has reduced final waste and improvised the properties of pigment.

This study comprises collective information regarding modern pre-treatment for extraction over conventional pre-treatments. The study also covers future trends and certain new hybrid approaches which are still less flourished.

The purpose of this paper is to study the effect of heat adaptation, pH adjustment, and the combination pretreatments to the resistance of Lactobacillus paracasei SNP2 in heat shock and spray drying.

Sub-lethal and lethal temperature range of L. paracasei SNP2 was determined by enumeration of cell survival after incubation at 37-55°C for 30 min. A certain temperature from sub-lethal range was selected for heat adaptation. Heat adaptation (H), pH adjustment (pH), and combination of pretreatments (pH-H) were applied prior to heat shock and spray drying.

The selected condition for heat adaptation and heat shock is 44°C, 30 min and 55°C, 15 min, respectively, based on the sub-lethal and lethal temperature range. By heat shock, cells in the whey-sucrose medium showed cell death of 2.05 log cycles, lower than cell death in the MRS medium of 4.84 log cycles. The pretreatments showed slight increase of heat resistance in cell grown in whey sucrose. The effect of H, pH, and pH-H pretreatments highly increase heat resistance of cell grown in MRS indicated by cell death of 4.27, 3.79, and 2.43 log cycles, respectively, which is much lower than control. The pretreatments showed no significant effect to L. paracasei SNP2 survival to spray drying.

This is the first study of L. paracasei SNP2 resistance to heat shock and spray drying. This paper also enriches information about application of whey sucrose as a growth medium and a heating medium.

The purpose of this study is to investigate the effect of plasma pretreatment on the corrosion and adhesion behavior of Al coating deposited on iron steel by ion vapor deposition (IVD).

Ar plasma sputtering was carried out for 0, 5, 10 and 15 min, and then IVD Al coating was performed. Surface free energy measurements were conducted on the plasma-sputtered surfaces. Cross-sectional observations were carried out on the coating/substrate interface by using scanning electron microscopy. Corrosion resistance of the deposited films was characterized using potentiodynamic polarization curve test and electrochemical impedance spectroscopy (EIS).

Results demonstrated that surface free energy values were increased by increasing the sputtering time before coating process. The corrosion current density of the IVD Al coating deposited after 15 min Ar plasma pretreatment is three orders of magnitude lower than that of steel ST37 substrate. The EIS tests confirm the excellent anticorrosive properties of the Al-coated specimens.

With the increase in the plasma pretreatment time, coating adhesion would ameliorate because of the presence of plasma, which makes substrates a better place for Al ions to set and prevent any gap between coatings and substrates. This fact can be attributed to an increase in the surface free energy and reduction of contact angle of substrate exposed to plasma pre-treatment.

The purpose of this paper was to find out the appropriate enzymatic hydrolysis conditions of alkali pretreated olive pomace (OP) which enable maximum yield of reducing sugar.

The commercial enzymatic preparation (Viscozyme^® L) was used for the hydrolysis of OP. The effects of pretreatment, time, temperature, pH, enzyme quantity and substrate loading on the hydrolysis yield were investigated.

This study showed that enzymatic hydrolysis of OP using Viscozyme^® L can be successfully performed at 50°C. Alkaline pretreatment step of OP prior the enzymatic hydrolysis was indispensable. The hydrolysis yield of alkaline pretreated OP was 2.6 times higher than the hydrolysis yield of untreated OP. Highest hydrolysis yield (33.5 ± 1.5 per cent) was achieved after 24 h using 1 per cent (w/v) OP load in the presence of 100 μl Viscozyme^® L at 50°C and pH 5.5 with mixing rate of 100 rpm (p = 0.05).

Reaction time, temperature, pH value and enzyme quantity were found to have a significant effect on enzymatic hydrolysis yield of alkali pretreated of OP. Although high-solid loadings of OP lowered the hydrolysis yield, it produced higher concentration of reducing sugars, which may render the OP conversion process more economically feasible.

Many articles have been written on the chemistry of phosphate pretreatment processes and the subject has been well documented. The aim of this article is to cover the practical application of phosphate pretreatments prior to wet paint and powder coat finishing.

The purpose of this paper is to investigate straw modification by chemical degradation generated by two forms of pretreatment, using citric acid in an autoclave and urea solution with sodium hydroxide at low temperature.

The material was digested and compared in biodigester reactors lined with natural straw, straw pretreated with citric acid, straw pretreated with urea and NaOH, and straw subjected to both the pretreatments. The amount of straw has been delimited to 0, 2.5, 5, 7.5 and 10 percent v/v, and used 20 percent v/v inoculum in all reactors, consisting of 30 percent v/v poultry litter and 70 percent swine wastewater (SW). The experiment was conducted in an incubator kept in mesophilic conditions (35°C).

The results indicate significant change in the studied material, with degradation of lignin as well as hemicellulose and cellulose exposed to further hydrolysis. Spectrophotometric methods were used for monitoring degradation. These methods were efficient in monitoring changes caused by the treatments. When the proposed pretreatments are applied to sugarcane straw, there is a significant gain in biogas production (L g VSR⁻¹). The most appropriate rates for higher methane production in the pretreatments are 2.5 and 5 percent straw-SW. The best results for the anaerobic digestion of sugarcane straw were obtained by pretreating it with citric acid.

This paper shows a new use for the sugarcane straw waste after being pretreated with acid or base for the coproduction of biogas.

This paper focuses on the effect of different pretreatments on some properties of tigernut, an underutilized crop in Nigeria with the aim of widening its utilization in the country.

Tigernuts were subjected to various pretreatments such as fermentation, germination, pregelatinization and roasting before drying at 50 ± 2 ^○C for 48 h in locally fabricated cabinet drier and milling in commercial plate mill to produce meal which passed through 30 mm pore‐sized sieve. Pretreated and untreated tigernut meals were analyzed using methods reported in the literature for chemical composition, physicochemical and functional properties.

Protein content of the meals ranged from 2.79 ± 0.01 to 3.65 ± 0.02 per cent with sample from fermented tigernut having the highest value and those from roasted ones having the least value. There were slight variations in the crude fat, fiber and ash contents of the resultant meals after pretreatment. There were 10 and 14 per cent enhancement in the ascorbic acid contents of fermented and germinated meals respectively. Titratable acidity, pH and water absorption capacity were affected by pretreatment in this study. Bulk density varied slightly after pretreatment. Germination, roasting and pregelatinization resulted in marked decrease in peak viscosity of the samples. The emulsion capacity ranged from 48.4 to 56 per cent with the untreated sample having the highest value and meals from roasted sample had the least value. Foaming capacity was improved by the pretreatments with the exception of roasting which reduced it from 2.15 to 1.18 per cent.

The paper has demonstrated the effect of pretreatments on tigernut meals and its potential applications in various food formulation and development, e.g. weaning foods, baked goods, beverage products, etc.