Optimal Conditions For Production Research Articles

Statistical modeling and optimization of volatile fatty acids production by anaerobic digestion of municipal wastewater sludge.

Obtaining value-added products from renewable resources is limited by the lack of specific operating conditions optimized for the physico-chemical characteristics of the biomass and the desired end product. A mathematical model and statistical optimization were developed for the production of volatile fatty acids (VFAs) by anaerobic digestion of municipal sewage sludge. The experimental tests were carried out in triplicate and investigated a wide range of conditions: pH 9.5, 10.5, and 11.5; temperatures 25°C, 35°C, 45°C, and 55°C; primary sludge with organic loading (OL) of 10 and 14g VS (volatile solids); and digested sludge with 4 and 6g VS. Subsequently, a statistical search was performed to obtain optimal production conditions, then a statistical model of VFA production was developed and the optimal conditions were validated at pilot plant scale. The maximum VFA concentration predicted was 6975mg COD (chemical oxygen demand)/L using primary sludge at 25°C, initial OL of 14g VS, and pH 10.5. The obtained third-degree model (r2 = 0.83) is a powerful tool for bioprocess scale-up, offering a promising avenue for sustainable waste management and biorefinery development.

Optimization and purification of L-methioninase enzyme purified from clinical samples of Pseudomonas spp.

Background: This study focused on Pseudomonas aeruginosa, which secrete important enzymes in medical and pharmaceutical applications and are isolated from clinical samples. One of these enzymes is L-methioninase, the most desirable enzyme in the medical and industrial fields today since it converted L-methionine into methanethiol, ammonia, and alpha-ketobutyrate. Objectives: Evaluated the optimum conditions of L-methioninase production and then purified it. Methods: Pseudomonas samples were identified by microscopic and biochemical tests and confirmed with the VITEK2 system. After the L-methioninase production was examined, the optimal conditions for the production of L-methioninase (MGL) were established using clinical samples of P. aeruginosa. Additionally, MGL was purified from the supernatant of P.aeruginosa using ammonium sulfate precipitation, DEAE-cellulose, and Sephadex G150 accordingly. Results: There were 33 isolates of P.aeruginosa according to microscopic characteristics and biochemical tests, followed by the VITEK2 system to ensure identification. The optimization conditions were achieved when supplement media with sucrose 1% w\v, casein 1% w\v, pH 7, temperature 37oC, and incubation for 48hrs within the specific activity of 1.6, 3.3, 3.4, 3.4, and 3.5U\mg protein, respectively, and 4.6 fold the amount of the purified enzyme as compared to the crude enzyme. A single 55 kDa band on the SDS-PAGE indicates the enzyme is purified. Conclusions: P.aeruginosa can be an efficient source of L-methioninase, and this enzyme had better and higher specific activity after applying optimum conditions for it and purifying it.

Optimization of the anaerobic digestion process and the metabolic pathway of methanogenesis of Jerusalem artichoke straw with the mixed addition of iron filings and biochar

This study explored the feasibility of the mixed addition of iron filings and biochar in the anaerobic digestion of Jerusalem artichoke straw (JAS), using iron filings and biochar as mixed additives for mid-temperature batch anaerobic digestion experiments, and applied response surface methodology to investigate the interactive effects of different ratios of iron filings and biochar (FE/BC), solid content, and initial pH on the cumulative methane production from JAS. The results showed that the optimal conditions for methane production were an FE/BC of 2.45:7.55, an initial pH of 7.59, and a solid content of 8.80 %. Under these conditions, the cumulative methane production was 278.11 mL g−1 volatile solid (VS) contents, which was very close to the predicted value (286.42 mL g−1 VS), with a relative error of less than 5 %, indicating the effectiveness of the model. The optimized conditions with mixed addition (HB) exhibited good synergistic promotion, increasing cumulative methane production by 48.69 % compared to the control without additives and by 22.29 % and 29.57 % compared to the single addition of iron filings and biochar, respectively. Moreover, the HB treatment under optimized conditions achieved good economic benefits. Metagenomic analysis showed that the relative abundances of bacterial taxa including Fermentimonas, DMER64, Bacteroidetes_VadinHA17, unclassified Synergistaceae, Clostridium, Ruminiclostridium, and unclassified Anaerolineaceae were higher in HB samples, and Methanothrix was also enriched. Methane metabolism pathway analysis indicated that the anaerobic digestion of JAS with the mixed addition of iron filings and biochar enhanced the acetoclastic methane production pathway, thereby increasing methane production.

Evaluation of wear and friction properties of graphite modified Lubri polylactic acid with various infill fabricated by additive manufacturing techniques

AbstractThree‐dimension (3D) printing technology, also known as additive manufacturing, is a manufacturing technology that creates three‐dimensional objects by depositing material layer by layer, as opposed to subtractive manufacturing methods. However, the newness of the technology brings with it many unknowns. In particular, the raw materials used are constantly increasing. For this reason, testing each raw material used in many aspects and to determine the optimum production conditions is important for the wide use of 3D printing technology. These optimal conditions may be the parameters used to produce a material, and sometimes they can appear as a new material. In addition, the production of new materials with varying production parameters is fundamental research topic that requires comprehensive study. For all these purposes, in this study, a new material type known as Lubri PLA (LPLA) was selected and produced in different filling types and subjected to a series of friction and wear tests. Thus, it is aimed to determine the tribological properties of the material. Additionally, samples were produced in ten different infill types (grid, lines, triangels, hexagon, cubic, octal, zigzag, diagonal, diagonal 3D and gyroid) to show the effect of filler type on friction and wear behavior. These filler types were used for both PLA and Lubri PLA materials and a total of twenty samples were produced. Thereby, it is aimed to conduct a comprehensive study showing the effect of both material difference and filling type on friction‐wear behavior. Diameter deviations, hardness deviations, friction coefficient, temperature, specific wear rates (SWr), and vibration were selected as output parameters. According to the analysis of the test results, the best result in terms of material structure was given by Lubri PLA, while the best result in terms of filling type was obtained with Diagonal 3D filling type. In addition, the lowest vibration level was obtained in the LP‐Diagonal 3D sample with 0.041 mm/s2, while the highest vibration level was obtained in the P‐Grid sample with 1.756 mm/s2.Highlights LPLA closed to nominal value in diameter and hardness deviations Addition of graphite nanoparticle increased the dimensional accuracy Diagonal 3D infill type Lubri PLA composites showed the superior performance Graphite modified Lubri PLA composites demonstrated superior performance

Optimization of Lipid Production of Rhodosporidium toruloides from Various Substrates

Background and Aim: In recent years, bioenergy has received a lot of attention from a technical point of view due to its ability to use reversible resources and its applicability worldwide. Biodiesel is a non-toxic, safe, renewable, and degradable fuel that is obtained from natural sources, such as vegetable oils, food waste oils, animal fats, algae, and microorganisms. This study aimed to optimize the lipid production of Rhodosporidium toruloides as a biofuel from different substrates. Materials and Methods: In this experimental laboratory study, after lipid extraction from Rhodosporidium toruloides CECT1137, cell biomass, nitrogen, and sugar consumption were measured according to the Bly and Dyer method. Then, using gas chromatography, the produced lipid compounds were identified, and lipid production was optimized by the one-factor method (type of nitrogen source and KH2PO4) and the Taguchi method (carbon and nitrogen source, temperature, pH, centrifuge, and time). Finally, the feasibility of mutation was investigated using UV to optimize lipid production. Results: The amount of lipid produced by Rhodosporidium toruloides was 4.95 g/l, which, after optimization by the Taguchi method, reached 8.54 g/l. Cell biomass, residual nitrogen, and consumed sugar were measured as 14.05, 0.19, and 28.85 g/l, respectively. Optimal production conditions were estimated by Taguchi, including 80 g/l carbon source, 1 g/l nitrogen source, 25 ° C, pH = 5.5, centrifuge at 180 rpm, and 96 hours. Most lipids produced were oleic acid and palmitic acid. Lipid production increased after UV exposure. Conclusion: The results showed that Rhodosporidium toruloides can accumulate a significant amount of lipid in its cells and can be a good alternative to plants and other sources of fuel production.

Process optimization in the pyroconversion of native sweet potato starch: structural and functional characterization of pyrodextrin

This work aims to produce dextrin from sweet potato (Ipomoea batatas) starch by pyroconversion. The effect of dextrinization process (roasting time, temperature, and hydrochloric acid concentration) on properties (structural and functional) of starch have been studied using central composite design of experiment. Reaction conditions included: roasting time (55 and 94 min), temperature (127 and 152 °C), and hydrochloric acid concentration (0.17 and 0.43 M). The temperature (quadratic effect X22) is highly significant on the three measured responses (p < 0.05) (Color Index (CI), Turbidity (Turb), and Saccharification Percentage (SP)). Also, the findings indicated that the two most important parameters influencing the pyroconversion of sweet potato starch in the current study were temperature (X2) and hydrochloric acid concentration (X3). The optimal conditions for dextrin production obtained are 94 min, 127 °C and 0.43 M for roasting time, temperature, and hydrochloric acid concentration respectively having 97% of solubility. The FTIR analysis revealed that OH, C-H, C-O, C–C and C-O–H were the main functional groups. These functional groups remained unaffected by the pyroconversion, since the bands extend and the spectrums of all native and pyrodextrin were similar. X-Ray Diffractometry analysis results of dextrin showed that the thermal treatment reduces the crystallinity of starch. Also, this analysis shows starch has CA-type XRD patterns. Scanning Electron Microscopy (SEM) analysis results showed that the defined optimal production maintains the morphology of starch. Differential scanning calorimetry (DSC) used for thermal analysis helps to obtain the glass transition temperature of modified starch equals to 139 °C. Optimal conditions of production of pyrodextrins from sweet potato granule starches could be easily produced with improved physicochemical properties to be used as encapsulating agent or additives in food and chemical industries.

Study of optimal nutritional conditions for Arbutin production from Bacillus subtilis NN2M

Arbutin is a combination of D-glucose and hydroquinone. Among the positive effects of arbutin are its antioxidant properties, antimicrobial properties and anti-inflammatory properties. Arbutin is one of the most important active compounds used to inhibit the enzyme tyrosinase, which causes enzymatic browning in many foods. Microbial fermentation has emerged as an up-and-coming technique for the production of arbutin in recent years. The aim of the study was the biological production of arbutin from Bacillus subtilis NN2M isolates. The isolates were confirmed and identified by Vitek and 16S rRNA and the nutritional conditions for production were improved to reach optimal conditions. To determine the best nutritional conditions for arbutin production, several conditions were studied, including the carbon source and its concentration, the nitrogen source and its concentration and the hydroquinone concentration. The results showed that the highest output of the active compound arbutin when using Molasses as a carbon source arbutin concentration was 23.34µg/mL. We also found the best concentration of the optimal carbon source, 4 % (w\v) arbutin concentration, was 27.62 µg/mL; furthermore, while using several nitrogen sources for producing arbutin, peptone was determined to be the optimum source, the concentration of arbutin was 47.3 µg/mL, the nitrogen source optimal Concentration was 2 % (w\v) arbutin concentration was 59.46 µg/mL, the optimum concentrations of hydroquinone was 2 % (w\v) arbutin concentration was 79.1 µg/mL.

Improved flame retardancy and mechanical properties of bacterial cellulose fabrics via solvent exchange and entrapment of zein and gluten

This study aimed to improve the flame retardancy and mechanical properties of bacterial cellulose (BC) by introducing cereal proteins, namely zein and gluten. The production conditions were determined by observing residual masses of samples at 1000 ℃ using thermogravimetric analysis (TGA). According to the TGA results, the optimized production conditions for the BCs with zein and gluten were combined solvent exchange and entrapment of 20 weight% (wt.%) of zein, and entrapment of 40 wt.% of gluten, respectively. Surface characterization of BC prepared with zein and gluten under the optimal conditions confirmed that the cereal proteins were incorporated into the BC nanostructures via solvent exchange and/or entrapment and the original chemical and crystal structures of BC were not significantly changed. Limiting oxygen index (LOI) analysis confirmed that cereal proteins improved the flame retardancy of BC. In particular, the LOI of BC entrapped with gluten was 50%, which was better than that of cowhide leather. Char morphology analysis confirmed that the as-produced BCs with cereal proteins exhibited condensed-phase flame-retardant mechanism by forming intumescent chars. Analysis of the mechanical properties confirmed that compared with cowhide leather, as-produced BCs with cereal proteins possessed high tensile strength and dimensional stability, making them suitable leather substitutes.

Microbial Biosynthesis of Medium-Chain-Length Polyhydroxyalkanoate (mcl-PHA) from Waste Cooking Oil.

Waste cooking oil is a common byproduct in the culinary industry, often posing disposal challenges. This study explores its conversion into the valuable bioplastic material, medium-chain-length polyhydroxyalkanoate (mcl-PHA), through microbial biosynthesis in controlled bioreactor conditions. Twenty-four bacterial isolates were obtained from oil-contaminated soil and waste materials in Mahd Ad-Dahab, Saudi Arabia. The best PHA-producing isolates were identified via 16S rDNA analysis as Neobacillus niacini and Metabacillus niabensis, with the sequences deposited in GenBank (accession numbers: PP346270 and PP346271). This study evaluated the effects of various carbon and nitrogen sources, as well as environmental factors, such as pH, temperature, and shaking speed, on the PHA production titer. Neobacillus niacini favored waste cooking oil and yeast extract, achieving a PHA production titer of 1.13 g/L, while Metabacillus niabensis preferred waste olive oil and urea, with a PHA production titer of 0.85 g/L. Both strains exhibited optimal growth at a neutral pH of 7, under optimal shaking -flask conditions. The bioreactor performance showed improved PHA production under controlled pH conditions, with a final titer of 9.75 g/L for Neobacillus niacini and 4.78 g/L for Metabacillus niabensis. Fourier transform infrared (FT-IR) spectroscopy and gas chromatography-mass spectrometry (GC-MS) confirmed the biosynthesized polymer as mcl-PHA. This research not only offers a sustainable method for transforming waste into valuable materials, but also provides insights into the optimal conditions for microbial PHA production, advancing environmental science and materials engineering.

Isolation, identification and characterization of neopullulanase from Thermomonas hydrothermalis GKE 08

The production of neopullulanase from thermophiles, such as Thermomonas hydrothermalis GKE 08, holds paramount significance due to the enzyme's unique thermophilic nature. Harnessing this characteristic ensures enhanced stability and functionality at elevated temperatures, a crucial aspect for industrial processes demanding efficient catalysis under extreme conditions. The investigation into pullulanase from T. hydrothermalis GKE 08 revealed significant findings. Optimal conditions for enzyme production were determined, with peak activity observed in the presence of 1.5% soluble pullulan and 0.5% peptone. The study delved into the pH and temperature dynamics, identifying an optimal pH of 7 and peak activity at 55 °C. Notably, the neopullulanase exhibited time-dependent stability, retaining 72% activity after 1 hour but declining to 50% after 2 hours. Furthermore, the enzyme displayed remarkable thermostability at 60 °C, with 88% activity after 30 minutes. Metal ion studies indicated susceptibility to inhibition by Cu2+, Mg2+, and Zn2+, while Ca2+ stimulated activity up to 138% at higher concentrations. The enzyme's response to specific reagents revealed sensitivity to SDS and EDTA, while urea surprisingly enhanced activity to 85%. The study enhances understanding of pullulanase behavior, offering valuable insights for biotechnological and industrial applications.

Energy-saving approach for mechanical properties enhancement of recycled PET additively manufactured by MEX

This study investigates the recycling of polyethylene terephthalate (PET) water bottles by material extrusion (MEX), an additive manufacturing (AM) technique, with a focus on characterising energy consumption and mechanical properties throughout the recycling process. The process encompasses shredding of the bottles, filament production, and the printing of tensile specimens. A full factorial design of experiment (DoE) was used to investigate the impact of various process parameters on product quality from an energy-saving perspective. The results provide important insights into energy efficiency and mechanical performance, identifying the optimal production conditions that balance environmental sustainability and material functionality. The results show that by optimizing printing parameters, energy consumption can be reduced by up to 30%, while the tensile strength of the printed samples can be increased by 20%. This research contributes to a broader understanding of the potential for AM in PET recycling, providing a pathway towards more localized and sustainable manufacturing practices.

Comparative genomic analysis and optimization of astaxanthin production of Rhodotorula paludigena TL35-5 and Rhodotorula sampaioana PL61-2.

Astaxanthin is a powerful antioxidant known to enhance skin, cardiovascular, eye, and brain health. In this study, the genome insights and astaxanthin production of two newly isolated astaxanthin-producing yeasts (TL35-5 and PL61-2) were evaluated and compared. Based on their phenotypic and genotypic characteristics, TL35-5 and PL61-2 were identified as basidiomycetous yeasts belonging to Rhodotorula paludigena and Rhodotorula sampaioana, respectively. To optimize astaxanthin production, the effects of cultural medium composition and cultivation conditions were examined. The optimal conditions for astaxanthin production in R. paludigena TL35-5 involved cultivation in AP medium containing 10 g/L glucose as the sole carbon source, supplemented with 1.92 g/L potassium nitrate, pH 6.5, and incubation at 20°C for 3 days with shaking at 200 rpm. For R. sampaioana PL61-2, the optimal medium composition for astaxanthin production consisted of AP medium with 40 g/L glucose, supplemented with 0.67 g/L urea, pH 7.5, and the fermentation was carried out at 20°C for 3 days with agitating at 200 rpm. Under their optimal conditions, R. paludigena TL35-5 and R. sampaioana PL61-2 gave the highest astaxanthin yields of 3.689 ± 0.031 and 4.680 ± 0.019 mg/L, respectively. The genome of TL35-5 was 20,982,417 bp in length, with a GC content of 64.20%. A total of 6,789 protein-encoding genes were predicted. Similarly, the genome of PL61-2 was 21,374,169 bp long, with a GC content of 64.88%. It contained 6,802 predicted protein-encoding genes. Furthermore, all essential genes involved in astaxanthin biosynthesis, including CrtE, CrtYB, CrtI, CrtS, and CrtR, were identified in both R. paludigena TL35-5 and R. sampaioana PL61-2, providing evidence for their ability to produce astaxanthin.

Characterization of protease-producing bacteria from garden soil and antagonistic activity against pathogenic bacteria

Bacteria play an essential role in various industrial processes, including food, medicine, and detergents, due to their ability to produce protease, a hydrolytic enzyme. This study aimed to identify and characterize protease-producing bacterial strains isolated from garden soil, evaluate their antibiotic susceptibility, and optimize conditions for enhanced protease production. Using skimmed milk agar medium and the gelatin hydrolysis method, 7 bacterial strains (S1, S2, S3, S4, S5, S6, and S7, respectively) were identified for protease production in garden soil. The bacteria were identified based on morphological studies, biochemical characterization, and the BIOLOG™ system, and the isolates were determined to be Bacillus cereus (S1), B. thuringiensis (S2), B. subtilis (S3), B. amyloliquefaciens (S4), Pseudomonas aeruginosa (S5), Macrococcus brunensis (S6), and B. schlegelii (S7). The antibiotic susceptibility test, performed using the Kirby-Bauer agar disc diffusion method, revealed that all isolates were resistant to penicillin, nitrofurantoin, and metronidazole. Additionally, B. subtilis and P. aeruginosa demonstrated antagonistic activity against pathogens. Optimal conditions for protease production were found to be a temperature range of 30°C to 40°C and a pH range of 6.5–7.5. Under these conditions, B. cereus (2.19 U/ml) and B. thuringiensis (2.12 U/ml) exhibited the highest protease activity. Further characterization of protease activity in B. cereus, P. aeruginosa, and M. brunensis under different physiological parameters revealed that maximum activity occurred within a pH range of 5.0–6.0 and temperatures between 30°C and 40°C. Protease activity increased in the presence of calcium (CaCl2) but decreased with the addition of urea. These findings underscore the significant industrial applications of proteases produced by these bacterial strains.

Parallel Multifactorial Process Optimization and Intensification for High-Yield Production of Live YF17D-Vectored Zika Vaccine.

The live-attenuated yellow fever 17D strain is a potent vaccine and viral vector. Its manufacture is based on embryonated chicken eggs or adherent Vero cells. Both processes are unsuitable for rapid and scalable supply. Here, we introduce a high-throughput workflow to identify suspension cells that are fit for the high-yield production of live YF17D-based vaccines in an intensified upstream process. The use of an automated parallel ambr15 microbioreactor system for screening and process optimization has led to the identification of two promising cell lines (AGE1.CR.pIX and HEKDyn) and the establishment of optimized production conditions, which have resulted in a >100-fold increase in virus titers compared to the current state of the art using adherent Vero cells. The process can readily be scaled up from the microbioreactor scale (15 mL) to 1 L stirred tank bioreactors. The viruses produced are genetically stable and maintain their favorable safety and immunogenicity profile, as demonstrated by the absence of neurovirulence in suckling BALB/c mice and consistent seroprotection in AG129 mice. In conclusion, the presented workflow allows for the rapid establishment of a robust, scalable, and high-yield process for the production of live-attenuated orthoflavivirus vaccines, which outperforms current standards. The approach described here can serve as a model for the development of scalable processes and the optimization of yields for other virus-based vaccines that face challenges in meeting growing demands.

Characterization and Enhanced Production of Fungal Melanin from Aspergillus Species Isolated from Soil

This study aimed to isolate and identify fungi from soil samples, focusing on their ability to produce melanin. Eleven different genera of fungi were isolated and identified using lactophenol cotton blue staining and microscopic examination, referencing H.L. Barnett and Barry B. Hunter. Among these, only Aspergillus was found to produce melanin. Optimal melanin production conditions were determined to be a 1.5% tyrosine supplement in the growth medium, under shaking conditions (120 rpm) and dark incubation for three weeks, resulting in a yield of 21.08 mg/100 ml. Physiochemical characterization revealed that the extracted melanin was insoluble in organic solvents but soluble in alkaline solutions (NaOH, KOH), and partially soluble in DMSO. Spectrometric analysis using UV-Visible spectroscopy showed characteristic absorption peaks. FTIR indicated functional groups and Scanning Electron Microscopy (SEM) images displayed a granular and heterogeneous surface topology. The study also assessed the effects of different carbon and nitrogen sources, and trace elements on melanin production. Maltose and sucrose were the most effective carbon sources, while peptone was the most effective nitrogen source. Among trace elements, calcium significantly enhanced melanin yield, while copper and zinc had moderate effects. These findings provide valuable insights into optimizing fungal melanin production and its potential industrial applications. The study highlights the sustainable and scalable production of melanin from Aspergillus, contributing to the broader understanding of fungal metabolites and their commercial exploitation. Future research should focus on genetic and metabolic pathways to further enhance melanin biosynthesis and explore its diverse applications.

Turning fish canning wastewater into resources: Effluents and operational conditions selection for volatile fatty acids production

The potential of three fish canning wastewaters to produce volatile fatty acids (VFA) was evaluated using a stepwise procedure at laboratory scale. Batch tests (0.5 L), at different food to microorganism ratios (F/M), presented tuna and mussel cooking wastewaters as the highest yield substrates (60 % and 80 %, respectively). F/M ratios tested did not significantly influence the yield or the VFA spectrum. Continuous reactors (5 L) were operated with these two wastewaters at different hydraulic retention times (HRT). The shortest HRT studied (2 d) favoured the yield and the production of longer-chain VFA (butyric and valeric acids) in tuna wastewater. However, for mussel wastewater, the yield decreased 2-fold and the production of short-chain VFA (acetic acid) was favoured. This study offers an overview of the best fish canning wastewater, from a point of view of maximum VFA yield, and its optimal operational conditions for VFA production.

Evaluation of Chemical and Physical Triggers for Enhanced Photosynthetic Glycerol Production in Different Dunaliella Isolates.

The salt-tolerant marine microalgae Dunaliella tertiolecta is reported to generate significant amounts of intracellular glycerol as an osmoprotectant under high salt conditions. This study highlights the phylogenetic distribution and comparative glycerol biosynthesis of seven new Dunaliella isolates compared to a D. tertiolecta reference strain. Phylogenetic analysis indicates that all Dunaliella isolates are newly discovered and do not relate to the D. tertiolecta reference. Several studies have identified light color and intensity and salt concentration alone as the most inducing factors impacting glycerol productivity. This study aims to optimize glycerol production by investigating these described factors singularly and in combination to improve the glycerol product titer. Glycerol production data indicate that cultivation with white light of an intensity between 500 and 2000 μmol m-2 s-1 as opposed to 100 μmol m-2 s-1 achieves higher biomass and thereby higher glycerol titers for all our tested Dunaliella strains. Moreover, applying higher light intensity in a cultivation of 1.5 M NaCl and an increase to 3 M NaCl resulted in hyperosmotic stress conditions, providing the highest glycerol titer. Under these optimal light intensity and salt conditions, the glycerol titer of D. tertiolecta could be doubled to 0.79 mg mL-1 in comparison to 100 μmol m-2 s-1 and salt stress to 2 M NaCl, and was higher compared to singularly optimized conditions. Furthermore, under the same conditions, glycerol extracts from new Dunaliella isolates did provide up to 0.94 mg mL-1. This highly pure algae-glycerol obtained under optimal production conditions can find widespread applications, e.g., in the pharmaceutical industry or the production of sustainable carbon fibers.

Producing Efficient Adsorbents from Kraft Lignin for the Removal of Contaminants from Water—A Full Factorial Design

This work aimed at optimizing the preparation of activated carbon (AC) from Kraft lignin for the adsorption of methylene blue (MB) and amoxicillin (AMX) from water. A full factorial design of three factors (precursor:activating agent (H3PO4) ratio, pyrolysis temperature, and residence time) at two levels was used to optimize the AC production. Eight AC products were obtained and evaluated considering the following responses: product yield, specific surface area (SBET), energy consumption, and adsorptive removal of the contaminants under study. The produced AC presented satisfactory SBET, ranging between 750 and 1335 m2 g−1, and efficient adsorption of MB and AMX from water, achieving up to 99% removal under the studied experimental conditions (100 mg L−1 of MB and AMX solution and material dose of 1 g L−1). Statistical analysis showed that product yield and energy consumption for AC production were influenced by temperature and residence time. The determination of a desirability function indicated a precursor/H3PO4 ratio of 1:2, pyrolysis at 700 °C, and residence time of 60 min as the optimal production conditions. The optimized AC presented SBET 1335 m2 g−1 and maximum adsorption capacity of 210 and 280 mg g−1 for MB and AMX, respectively.

Influence of protein-fat emulsion from turkey skin and plant raw materials on the quality of cooked sausages

The study examined the impact of a protein-fat emulsion (PFE) derived from turkey skin and green buckwheat flour on the quality of cooked sausages. The aim was to investigate how the addition of PFE affects various characteristics of the sausage. The experiments demonstrated that adding PFE up to 30% while stirring for up to 8 minutes at 10°C improved the sausage structure. This was evidenced by an increase in pH values to 6.5, water binding capacity to 71.2%, and ultimate shear stress to 321.86 Pa. It was observed that stuffing temperature and mixing time influenced pH, water binding capacity, and ultimate shear stress. The study identified the optimal production conditions and determined the maximum amount of PFE that can be added to sausages. Additionally, it was found that green buckwheat flour enhances the structure of the minced meat, raises pH, and increases water-binding capacity. Furthermore, PFE was noted to improve the appearance and flavor characteristics of the sausages. These findings highlight the potential of these new ingredients to enhance the quality of cooked sausages in the food industry.

Optimizing production conditions of innovative bio-pellets developed from flax straw

The increasing global demand for sustainable energy has prompted the utilization of agricultural residues as viable alternatives to traditional fossil fuels. This study specifically focuses on the utilization of flax straw, a substantial by-product in Canadian agriculture, to produce innovative biofuels through the process of pelletization. To enhance the quality of the pellets, lignin extracted from flax straw was introduced as a novel and natural pellet binder. A comprehensive investigation was conducted to analyze effect of various parameters, including flax straw particle size, binder (lignin) content, moisture levels, and pelletization conditions on quality of produced pellets. It was observed that at a compressive force of 4000 N and a die temperature of 95 °C, pellets made from larger flax straw particles (300–355 µm) exhibited a density of 1016 kg/m³ and a mechanical durability of 26.4 %. Subsequently, by reducing the particle size to 75–106 µm, a marked enhancement in both density (1072 kg/m³) and durability (86.1 %, a 2.3-fold increase) was achieved. The incorporation of 10 % lignin into medium-sized flax straw particles (150–212 µm) increased pellet durability by 18.6 % from 73.5 % to 87.2 %. Introducing an optimal moisture content of 14 % to the flax straw resulted in a notable increase in both density (from 1036 to 1154 kg/m³) and durability (from 73.5 % to 90.6 %, a 23.3 % increase). Compressive force and die temperature positively affected pellet quality. Elevating the temperature from 75 to 115 °C in pellets made from 150 to 212 µm flax straw, modified with 10 % lignin and 14 % moisture content, led to a significant improvement in both density (1179 kg/m³) and durability (96.6 %, a 11.9 % increase). Physiochemical characteristics of flax straw, lignin, and the resulting pellets were explored using various techniques such as Fourier transform infrared, thermogravimetric analysis, and differential scanning calorimetry. These comprehensive investigations offer valuable insights for optimizing pellet materials and pelletization conditions and promoting the sustainable utilization of agricultural residues for bioenergy production.