Removal of heavy metal vanadium from aqueous solution by nanocellulose produced from Komagataeibacter europaeus employing pineapple waste as carbon source

Characterization and evaluation of the adsorption of uremic toxins through the pyrolysis of pineapple leaves and peels and by forming a bio-complex with sodium alginate

This study was performed to develop an optimal process for manufacturing activated carbon (AC) from pineapples' off-cuts (leaves and peels; PL and PP) by pyrolysis and for forming a bio-complex with sodium alginate (CA). In addition, the physicochemical properties were also explored under different preparation conditions, and the effects of adsorbed uremic toxins in three simulated gastrointestinal conditions (in vitro) were evaluated. This study showed that pyrolysis at 800 °C and activation by CO2 (30 min) resulted in satisfactory porous profiles with high specific surface areas of 388.79 and 536.84 m2/g for PLAC and PPAC, respectively. Regarding appearance and microstructures, there are still discernible disparities compared to the AST in regular service, while it exhibits a similar peak shape to that of the AC under the Raman spectrometer. Remarkably, the adsorption capacity of PLAC and PPAC for uremic toxins was best for indole adsorption while providing a consistent effect with AST. Indole-3-acetic acid (3-IAA) and p-cresol (p-C) adsorption capacities were the second highest. Nevertheless, AST also exhibited varying degrees of reduced adsorption capacity under different gastrointestinal simulation conditions. Therefore, this study conditions the development of cost-effective adsorbent products targeting uremic toxins, which could generate novel synergistic systems based on pineapple by-products within the circular economy framework.

Improved bacterial cellulose production by Acetobacter oryzoeni MGC-N8819 in tobacco waste extract coupled with nicotine removal by Pseudomonas sp. JY-Q/5∆

As the substrate, tobacco waste extract (TWE) can produce bacterial cellulose (BC), a biobased material. However, nicotine inhibits BC production (adding 0.8 g/L nicotine to the HS medium had a negative effect on BC synthesis) and needs to be removed. In this study, BC production by Acetobacter oryzoeni MGC-N8819 was carried out in four dilutions (5 %, 10 %, 15 %, and 20 %) of TWE. 15 % TWE without nicotine removal resulting in a 3.27 g/L BC production. Considering the inhibitor effect of nicotine on BC synthesis. Pseudomonas sp. JY-Q/5∆, an efficient nicotine-degrading mutant strain without the ability of glucose consumption, was statically co-cultured with MGCN8819, and the BC production was increased to 4.61 g/L after 7 days of cultivation. To eliminate the limitation of insufficient oxygen supply, BC films were harvested on day 7 and cultured for an additional 5 days resulting in a 6.00 g/L final BC production. Remarkably, the co-culture of MGC-N8819 and JY-Q/5∆ improved BC properties in terms of fiber diameter (28 nm), mechanical properties (tensile strength to 67 MPa and elongation at break to 23 %), and thermal stability (the maximum decomposition temperature was 600 °C). This study suggests a valuable strategy for improving BC production using agricultural waste.

Applications and Advantages of Cellulose-Chitosan Biocomposites: Sustainable Alternatives for Reducing Plastic Dependency

This review presents a comprehensive review of cellulose-chitosan-based biocomposites that have high potential as sustainable alternatives to synthetic polymers. These biocomposites, due to biocompatibility, biodegradability, and antimicrobial properties, attract attention for wide application in various industries. This review includes modern methods for producing cellulose-chitosan composites aimed at improving their mechanical and chemical properties, such as strength, flexibility, and water resistance. Particular attention is paid to the use of composites in packaging materials, where they provide protection and durability of products, and help reduce the environmental footprint. In medicine, such composites are used for drug delivery and tissue engineering, providing controlled release of active substances and tissue regeneration. In addition, their advantages in wastewater treatment are discussed, where the composites effectively remove heavy metal ions and organic pollutants due to their high sorption capacity. This study focuses on the wide potential of cellulose-chitosan biocomposites and their role in solving environmental problems.

Marine vanadium pollution: Sources, ecological impacts and cutting-edge mitigation strategies

Vanadium (V) is a hazardous element with widespread environmental presence, particularly in marine environments, due to both natural and industrial sources. This review examines vanadium's impact on marine organisms, highlighting its disruption of metabolic processes in fish, microalgae, and crustaceans, leading to oxidative stress, impaired growth and reproduction. Vanadium accumulation in marine food chains poses risks to higher organisms, including humans. Conventional vanadium removal methods, e.g., filtering and reverse osmosis, are costly and energy-intensive. Alternatively, bioremediation offers a sustainable solution, particularly using microalgae and thraustochytrids. Microalgae can detoxify and immobilize vanadium through adsorption and biodegradation, contributing to carbon capture and producing value-added products. Advances in bioprocess engineering, including regulating key parameters such as temperature and pH during biomass harvesting and using chelating agents, have enhanced this bioremediation approach, making it a viable option for industrial-scale applications and aligning with Sustainable Development Goals by integrating environmental protection with renewable energy production.

Green reduction of ZnO nanoparticles using cationic dialdehyde cellulose (cDAC) for efficient Congo red dye removal

More sustainable materials have been becoming an important concern of worldwide scientists, and cellulosic materials are one alternative in water decontamination. An efficient strategy to improve removal capacity is functionalizing or incorporating nanomaterials in cellulose-based materials. The new hybrid cDAC/ZnONPs was produced by green synthesis of zinc oxide nanoparticles (ZnONPs), promoting the in situ reduction and immobilization on the cationic dialdehyde cellulose microfibers (cDAC) surface to remove Congo red dye from water. cDAC/ZnONPs was characterized by scanning electron microscopy (SEM-EDS) and infrared spectroscopy (FTIR), which showed efficient nanoparticles reduction. Adsorption efficiency on cationic cellulose surface was investigated by pH, contact time, initial concentration, and dye selectivity tests. The material followed the H isotherm model, which resulted in a maximum adsorption capacity of 1091.16 mg/g. Herein, was developed an efficient and ecologically correct new adsorbent, highly effective in Congo red dye adsorption even at high concentrations, suitable for the remediation of contaminated industrial effluents.

Innovative approaches for amino acid production via consolidated bioprocessing of agricultural biomass

Agricultural plantations in Indonesia and Malaysia yield substantial waste, necessitating proper disposal to address environmental concerns. Yet, these wastes, rich in starch and lignocellulosic content, offer an opportunity for value-added product development, particularly amino acid production. Traditional methods often rely on costly commercial enzymes to convert biomass into fermentable sugars for amino acid production. An alternative, consolidated bioprocessing, enables the direct conversion of agricultural biomass into amino acids using selected microorganisms. This review provides a comprehensive assessment of the potential of agricultural biomass in Indonesia and Malaysia for amino acid production through consolidated bioprocessing. It explores suitable microorganisms and presents a case study on using Bacillus subtilis ATCC 6051 to produce 9.56 mg/mL of amino acids directly from pineapple plant stems. These findings contribute to the advancement of sustainable amino acid production methods using agricultural biomass especially in Indonesia and Malaysia through consolidated bioprocessing, reducing waste and enhancing environmental sustainability.

A sustainable bioprocess to produce bacterial cellulose (BC) using waste streams from wine distilleries and the biodiesel industry: evaluation of BC for adsorption of phenolic compounds, dyes and metals

BACKGROUND

The main challenge for large-scale production of bacterial cellulose (BC) includes high production costs interlinked with raw materials, and low production rates. The valorization of renewable nutrient sources could improve the economic effectiveness of BC fermentation while their direct bioconversion into sustainable biopolymers addresses environmental pollution and/or resource depletion challenges. Herein a green bioprocess was developed to produce BC in high amounts with the rather unexplored bacterial strain Komagataeibacter rhaeticus, using waste streams such as wine distillery effluents (WDE) and biodiesel-derived glycerol. Also, BC was evaluated as a bio-adsorbent for phenolics, dyes and metals removal to enlarge its market diversification.

RESULTS

BC production was significantly affected by the WDE mixing ratio (0-100%), glycerol concentration (20-45 g/L), type of glycerol and media-sterilization method. A maximum BC concentration of 9.0 g/L, with a productivity of 0.90 g/L/day and a water holding capacity of 60.1 g water/g dry BC, was achieved at 100% WDE and ≈30 g/L crude glycerol. BC samples showed typical cellulose vibration bands and average fiber diameters between 37.2 and 89.6 nm. The BC capacity to dephenolize WDE and adsorb phenolics during fermentation reached respectively, up to 50.7% and 26.96 mg gallic acid equivalents/g dry BC (in-situ process). The produced BC was also investigated for dye and metal removal. The highest removal of dye acid yellow 17 (54.3%) was recorded when 5% of BC was applied as the bio-adsorbent. Experiments performed in a multi-metal synthetic wastewater showed that BC could remove up to 96% of Zn and 97% of Cd.

CONCLUSIONS

This work demonstrated a low-carbon approach to produce low-cost, green and biodegradable BC-based bio-adsorbents, without any chemical modification. Their potential in wastewater-treatment-applications was highlighted, promoting closed-loop systems within the circular economy era. This study may serve as an orientation for future research towards competitive or targeted adsorption technologies for wastewater treatment or resources recovery.

Biotechnological innovations in nanocellulose production from waste biomass with a focus on pineapple waste

New materials' synthesis and utilization have shown many critical challenges in healthcare and other industrial sectors as most of these materials are directly or indirectly developed from fossil fuel resources. Environmental regulations and sustainability concepts have promoted the use of natural compounds with unique structures and properties that can be biodegradable, biocompatible, and eco-friendly. In this context, nanocellulose (NC) utility in different sectors and industries is reported due to their unique properties including biocompatibility and antimicrobial characteristics. The bacterial nanocellulose (BNC)-based materials have been synthesized by bacterial cells and extracted from plant waste materials including pineapple plant waste biomass. These materials have been utilized in the form of nanofibers and nanocrystals. These materials are found to have excellent surface properties, low density, and good transparency, and are rich in hydroxyl groups for their modifications to other useful products. These materials are well utilized in different sectors including biomedical or health care centres, nanocomposite materials, supercapacitors, and polymer matrix production. This review explores different approaches for NC production from pineapple waste residues using biotechnological interventions, approaches for their modification, and wider applications in different sectors. Recent technological developments in NC production by enzymatic treatment are critically discussed. The utilization of pineapple waste-derived NC from a bioeconomic perspective is summarized in the paper. The chemical composition and properties of nanocellulose extracted from pineapple waste may have unique characteristics compared to other sources. Pineapple waste for nanocellulose production aligns with the principles of sustainability, waste reduction, and innovation, making it a promising and novel approach in the field of nanocellulose materials.

Microalgae and nano-cellulose composite produced via a co-culturing strategy for ammonia removal from the aqueous phase

This study addresses the pressing need for sustainable bioremediation solutions to combat increasing pollution challenges in alignment with sustainability development goals. The research focuses on developing a co-culture approach involving microalgae and Komagataeibacter europaeus BCRC 14148 bacterium to create a biocomposite for efficient ammonia removal. Nanocellulose, produced by the bacterium, serves as a substrate for microalgae attachment. Optimization using specific growth media ratios resulted in biocomposite yields of 4.05 ± 0.16 g/L and 3.83 ± 0.13 g/L in HS medium with fructose and glucose, respectively. The optimal conditions include a 40:60 ratio of HS-F to TAP medium, 25 ℃ incubation, 6000 Lux light intensity, pH 5.5, and a 48-hour incubation period. When applied to wastewater treatment, the biocomposite demonstrated exceptional ammonium removal efficiency at 91.64 ± 1.27 %. This co-culture-derived biocomposite offers an eco-friendly, recyclable, and effective solution for sustainable environmental bioremediation.

A circular biorefinery approach for the production of xylooligosaccharides by using mild acid hydrothermal pretreatment of pineapple leaves waste

A hydrothermal process is a sustainable approach for biorefinery leading to conversion of lignocellulosic (LC) biomass into value-added products. This study is based on the production of xylooligosaccharides (XOS) from pineapple leaves (PL) waste by using mild acid like gluconic acid (GA). GA, when used as catalyst in hydrothermal process to produce XOS the yield improved. The above process can be integrated with bacterial cellulose (BC) production bioprocess via Komagataeibacter europaeus 14,148 where gluconic acid is produced as by-product. Maximum XOS (2-5 degree of polymerisation) yield of 67.79 % in the liquid fraction was obtained via hydrothermal treatment at 160 °C for 60 min with 5% gluconic acid concentration. It is based on the selective solubilization of hemicellulose fraction. Enzymatic hydrolysis of GA hydrothermally pretreated solid fraction of PL biomass gave 14.5 g/L glucose with 5% solid loading and 10 FPU/gds enzyme loading which was employed for Bacterial cellulose production.

Current advances of nanocellulose application in biomedical field

Nanocellulose (NC) is a natural fiber that can be extracted in fibrils or crystals form from different natural sources, including plants, bacteria, and algae. In recent years, nanocellulose has emerged as a sustainable biomaterial for various medicinal applications including drug delivery systems, wound healing, tissue engineering, and antimicrobial treatment due to its biocompatibility, low cytotoxicity, and exceptional water holding capacity for cell immobilization. Many antimicrobial products can be produced due to the chemical functionality of nanocellulose, such disposable antibacterial smart masks for healthcare use. This article discusses comprehensively three types of nanocellulose: cellulose nanocrystals (CNC), cellulose nanofibrils (CNF), and bacterial nanocellulose (BNC) in view of their structural and functional properties, extraction methods, and the distinctive biomedical applications based on the recently published work. On top of that, the biosafety profile and the future perspectives of nanocellulose-based biomaterials have been further discussed in this review.

A sustainable vanadium bioremediation strategy from aqueous media by two potential green microalgae

Globally, environmental concerns are rapidly growing due to increasing pollution levels. Vanadium is a hazardous heavy metal that poses health issues with an exposure concentration of about 2 ppm. It is regularly discharged by some industries and poses an environmental challenge. There are no sustainable green treatment methods for discharged effluents to mitigate vanadium threats to humans and the environment. In this study, the goal was to develop a green, sustainable method for removing vanadium and to utilize the produced biomass for biofuels, thus offsetting the treatment cost. Microalgae Chlorella sorokiniana SU1 and Picochlorum oklahomensis were employed for vanadium (III) treatment. The maximum removal was 25.5 mg L^-1 with biomass and lipid yields of 3.0 g L^-1 and 884.4 mg L^-1 respectively after 14 days of treatment. The vanadium removal capacity by microalgae was further enhanced up to 2-2.7 folds while optimizing the key parameters, pH, and temperature before removing biomass from the liquid phase. FTIR is used to analyse the reactive groups in algal cell walls to confirm vanadium adsorption and to understand the dominant and quantitative interactions. Zeta potential analysis helps to find out the most suitable pH range to facilitate the ionic bonding of biomass and thus maximum vanadium adsorption. This study addresses regulating external factors for enhancing the removal performance during microalgal biomass harvesting, which significantly enhances the removal of vanadium (III) from the aqueous phase. This strategy aims to improve the removal efficiency of microalgal treatment at an industrial scale for the bioremediation of vanadium and other inorganic pollutants.