Search Results (52)

The global market size of animal parasiticides was valued at USD 12.9 billion in 2024. Animal deworming only results in temporary cures with little to no preventive effects; therefore, a strategy that combines animal deworming with prevention is essential in improving the control of helminths. The effectiveness of co-administrating curative and preventive agents and their compatibility were considered based on the parasitophagous fungus Mucor circinelloides, which was developed in edible agar–agar (red seaweed)-carrying dewormers. Accordingly, Petri dishes were prepared with either a biopolymer alone (control, G-C) or with the anthelmintic piperazine (550, 1102, 2210, and 5500 mg/plate) or levamisole (37.5, 75, 150, and 300 mg/plate) and were used to culture the fungus Mucor circinelloides. Strong fungal growth and high numbers of spores were observed in the presence of the anthelmintics. No differences were measured between the control plates and those containing parasiticide drugs. Similar mycelial growth patterns and sporogenesis rates were recorded for different amounts of each anthelmintic. In conclusion, this novel formulation based on biopolymers containing anthelmintics and enriched with the parasitophagous fungus represents a highly promising tool to consider for jointly deworming animals and minimizing the risks of helminth infection. Further studies are in progress to confirm these in vitro results. Full article

Low-plasticity silts (ML) found in Metro Manila, Philippines, characterized by low strength, stiffness, and bearing capacity, often require stabilization. Traditional methods using cement are associated with significant carbon emissions, causing environmental concerns. Sustainable materials such as agar biopolymers can be an alternative to cement to improve the strength of fine-grained soils. A comparative study was conducted on ML samples treated with agar and cement at different concentrations (1%, 3%, 5%, and 7%) and subjected to varying curing periods (7, 21, 28, and 35 days) under air-dried conditions using Unconfined Compressive Strength (UCS) tests. Agar-treated samples generally exhibited higher UCS values than cement-treated samples across the tested concentrations and curing periods. Samples with 3% and 5% agar were significantly stronger than their cement-treated counterparts. The strength of agar-treated soils peaked at a 5% concentration and subsequently decreased at 7% agar, possibly due to a masking effect. SEM-EDS analysis revealed that a 5% agar concentration achieved a balanced microstructure with effective particle bonding, while higher concentrations led to diminished strength due to reduced mechanical interlocking from excessive biopolymer coverage. Subsequent statistical analysis also indicated significant improvement using agar versus cement-treated and untreated soils, especially at 5% agar. A predictive polynomial regression model demonstrated the influence of curing days and agar concentration on UCS, attaining R² = 0.94 vs. experimental values. Using agar biopolymers presents a promising and potentially more sustainable approach to soil, highlighting the potential of utilizing a locally abundant resource for geotechnical engineering applications. Full article

Sustainable agriculture increasingly relies on biocontrol agents as eco-friendly solutions to combat plant diseases while improving soil health. In this context, species of the genus Bacillus, particularly Bacillus subtilis, have shown promise as effective biocontrol agents for plant diseases. This study demonstrates the successful fabrication of biohybrid materials by decorating electrospun poly(3-hydroxybutyrate) (PHB) fibers with electrosprayed chitooligosaccharide (COS) and Bacillus subtilis using simultaneous electrospinning and electrospraying. During electrospraying, COS formed a uniform film over the PHB fibers, serving as both an adhesive and a protective coating that maintained the viability and functionality of the embedded bacteria. SEM confirmed that bacterial spores were uniformly spread across the COS-coated biopolymer fibers. ATR-FTIR spectroscopy verified the successful deposition of COS on the fibers, while mechanical assay demonstrated enhancement in mechanical characteristics after the COS film formation on the PHB fibers compared to uncoated PHB. In addition, COS improved the wetting properties of the fibrous PHB material, creating a favorable environment for bacterial growth and development. Microbiological tests showed that the embedded B. subtilis remained viable and proliferated normally after 48 h under suitable conditions at 28 °C on agar medium. Furthermore, the biohybrid COS/B. subtilis-on-PHB materials also effectively inhibited the growth of pathogenic fungi, including species of Alternaria and Fusarium. These findings highlight the potential of dual electrospinning/electrospraying techniques for the fabrication of eco-friendly biocontrol formulations. The integration of COS coatings with B. subtilis provides a promising approach for sustainable agriculture by combining enhanced material properties with effective antifungal activity. Full article

Polysaccharides represent the most abundant biopolymers in agri-food wastes and thus are the most studied polymers to produce biodegradable films for use in packaging. Starch is among the major polysaccharides extracted from food and agricultural waste that have been used as precursor material for film production. Therefore, the present study aimed at producing an active film with antimicrobial properties using starch extracted from cassava waste and oil extracted from cloves. The antimicrobial activity of the produced films was tested against Staphylococcus aureus, Salmonella Typhimurium and Listeria monocytogenes. Cassava periderm and cortex were bleached with either NaClO or H₂O₂ before starch aqueous extraction. The active films’ antimicrobial effectiveness was assessed by the formation of inhibitory halos around film disc samples in an agar diffusion method. The inhibition zone diameters were statistically similar for all microorganisms, with an average diameter of 11.87 ± 1.62 mm. The films presented an average water vapor permeability of 0.14 g mm/m² h kPa, an average tensile strength of 0.17 MPa and an elongation at break of 32.90%. Based on the determined properties, the produced films were deemed adequate for use in food packaging, in which antimicrobial activity is paramount. Full article

The probiotic bacterium Bifidobacterium animalis subsp. lactis BB-12 (BB-12) was encapsulated in two composites, alginate/agar and alginate/agar/casein. The network structure and physicochemical properties of these composites are influenced by complex interactions, including hydrogen bonding, electrostatic forces between biopolymers, calcium ions, and the encapsulated bacteria. The composites demonstrated a granular surface, with the granules being spatially oriented on the alginate/agar/BB-12 surface and linearly oriented on the alginate/agar/casein/BB-12 surface. They possess a highly organized microparticle structure and exhibit viscoelastic solid-like behavior. The alginate/agar/BB-12 composite showed higher storage modulus, shear stress, and shear strain values, indicating enhanced stability in various physical environments. Both composites displayed good thermal stability, aligning with their rheological properties, confirming their well-ordered structures. Despite differences in composite structures, the release mechanism of bacteria is governed by Fickian diffusion through the composite matrix. Based on physicochemical properties, the alginate/agar/casein composite is recommended for dairy product fermentation, while the alginate/agar composite seems more suitable for oral use. These findings provide new insights into the interactions between bacterial cultures and alginate composite ingredients. Full article

This review details the extraction, characterization and utilization of seaweed-derived biopolymers for future packaging applications. The review is contextualized within the broader scope of the challenge of plastic pollution and the current urgent need for more sustainable packaging materials. Macroalgae (or seaweed) has been highlighted as a promising source of biopolymers, most commonly sodium alginate, agar and carrageenan, for reasons such as a rapid growth rate and decreased environmental impact when compared with terrestrial plant life. Extraction methods detailed include traditional solvent-based extraction and more sustainable developments such as ultrasound-assisted extraction, microwave-assisted extraction and bead milling. This review additionally presents the characterization techniques most pertinent in determining the applicability of these biopolymers in packaging applications. Properties of key importance to the development of sustainable packaging materials such as thermal properties, mechanical strength, barrier properties and biodegradability are highlighted in comparison to conventional petroleum-based plastics. This review concludes by realistically identifying the challenges faced by implementing seaweed-based biopolymers into packaging structures, such as cost-effectiveness, scalability and performance while suggesting future directions to mitigate these issues and improve the commercial viability of these materials for the packaging industry. Full article

Biopolymers are polymers of natural origin and are environmentally friendly, carbon neutral and less energy-intense additives that can be used for various geotechnical applications. Biopolymers like xanthan gum, carrageenan, chitosan, agar, gellan gum and gelatin have shown potential for improving subgrade strength, erosion resistance, and as canal liners and in slope stabilization. But minimal research has been carried out on cellulose-based biopolymers, particularly microcrystalline cellulose (MCC), for their application in geotechnical and geo-environmental engineering. In this study, the effect of MCC on select geotechnical properties of kaolin, a weak, highly compressible clay soil, like its liquid and plastic limits, compaction behavior, deformation behavior, unconfined compression strength (UCS) and aging, was investigated. MCC was used in dosages of 0.5, 1.0, 1.5 and 2% of the dry weight of the soil, and the dry mixing method was adopted for sample preparation. The results show that the liquid limit increased marginally by 11% but the plasticity index was nearly 74% higher than that of untreated kaolin. MCC rendered the treated soil stiffer, which is reflected in the deformation modulus, which increased with both dosage and age of the treated sample. The UCS of kaolin increased with dosage and curing period. The maximum UCS was observed for a dosage of 2% MCC at a 90-day curing period. The increase in stiffness and strength of the treated kaolin with aging points out that MCC can be a potential soil stabilizer. Full article

The high demand for lithium (Li) relates to clean, renewable storage devices and the advent of electric vehicles (EVs). The extraction of Li ions from aqueous media calls for efficient adsorbent materials with various characteristics, such as good adsorption capacity, good selectivity, easy isolation of the Li-loaded adsorbents, and good recovery of the adsorbed Li ions. The widespread use of metal-based adsorbent materials for Li ions extraction relates to various factors: (i) the ease of preparation via inexpensive and facile templation techniques, (ii) excellent selectivity for Li ions in a matrix, (iii) high recovery of the adsorbed ions, and (iv) good cycling performance of the adsorbents. However, the use of nano-sized metal-based Lithium-ion sieves (LISs) is limited due to challenges associated with isolating the loaded adsorbent material from the aqueous media. The adsorbent granulation process employing various binding agents (e.g., biopolymers, synthetic polymers, and inorganic materials) affords composite functional particles with modified morphological and surface properties that support easy isolation from the aqueous phase upon adsorption of Li ions. Biomaterials (e.g., chitosan, cellulose, alginate, and agar) are of particular interest because their structural diversity renders them amenable to coordination interactions with metal-based LISs to form three-dimensional bio-composite materials. The current review highlights recent progress in the use of biopolymer binding agents for the granulation of metal-based LISs, along with various crosslinking strategies employed to improve the mechanical stability of the granules. The study reviews the effects of granulation and crosslinking on adsorption capacity, selectivity, isolation, recovery, cycling performance, and the stability of the LISs. Adsorbent granulation using biopolymer binders has been reported to modify the uptake properties of the resulting composite materials to varying degrees in accordance with the surface and textural properties of the binding agent. The review further highlights the importance of granulation and crosslinking for improving the extraction process of Li ions from aqueous media. This review contributes to manifold areas related to industrial application of LISs, as follows: (1) to highlight recent progress in the granulation and crosslinking of metal-based adsorbents for Li ions recovery, (2) to highlight the advantages, challenges, and knowledge gaps of using biopolymer-based binders for granulation of LISs, and finally, (3) to catalyze further research interest into the use of biopolymer binders and various crosslinking strategies to engineer functional composite materials for application in Li extraction industry. Properly engineered extractants for Li ions are expected to offer various cost benefits in terms of capital expenditure, percent Li recovery, and reduced environmental footprint. Full article

The geotechnical properties of clay soil and its mixtures with different proportions (0.75%, 0.85%, 1%, and 1.15%) of Agar Gum biopolymer and Ferrochromium Slag (0.25%, 0.50%, 0.75%, and 1%), having various curing times and freeze-thaw cycles, were studied through a series of soil mechanical tests to investigate possibilities to improve its undesired/problematic plasticity, compaction, and shear strength characteristics. The results revealed that treatment with an optimal ratio of 1% Agar Gum and 1% Ferrochromium Slag alone, as well as together with, improved the geotechnical properties of the clay soil considerably. Both the unconfined and shear strength properties, along with the cohesion and internal friction angle, increased as much as 47 to 173%, depending on the curing time. The higher the curing time, the higher the shear strength, cohesion, and internal friction angle are up to 21 days. Deteriorating the soil structure and/or fabric, freeze-thaw cycles, however, seem to have an adverse effect on the strength. The higher the freeze-thaw cycle, the lower the shear strength, cohesion, and internal friction angle. Also, some improvements in the plasticity and compaction properties were determined, and environmental concerns regarding Ferrochromium Slag usage have been addressed. Full article

Although Hantzsch synthesis has been an established multicomponent reaction method for more than a decade, its derivative, whereby an aniline replaces ammonium acetate as the nitrogen source, has not been explored at great length. Recent studies have shown that the products of such a reaction, N-aryl-4-aryldihydropyridines (DHPs), have significant anticancer activity. In this study, we successfully managed to synthesize a wide range of DHPs (18 examples, 8 of which were novel) using a metal-free, mild, inexpensive, recoverable, and biopolymer-based heterogeneous catalyst, known as piperazine, which was supported in agar–agar gel. In addition, 8 further examples (3 novel) of such dihydropyridines were synthesized using isatin instead of aldehyde as a reactant, producing spiro-linked structures. Lastly, this catalyst managed to afford an unprecedented product that was derived using an innovative technique—a combination of multicomponent reactions. Essentially, the product of our previously reported aza-Friedel–Crafts multicomponent reaction could itself be used as a reactant instead of aniline in the synthesis of more complex dihydropyridines. Full article

Non-degradable plastics of petrochemical origin are a contemporary problem of society. Due to the large amount of plastic waste, there are problems with their disposal or storage, where the most common types of plastic waste are disposable tableware, bags, packaging, bottles, and containers, and not all of them can be recycled. Due to growing ecological awareness, interest in the topics of biodegradable materials suitable for disposable items has begun to reduce the consumption of non-degradable plastics. An example of such materials are biodegradable biopolymers and their derivatives, which can be used to create the so-called bioplastics and biopolymer blends. In this article, gelatine blends modified with polysaccharides (e.g., agarose or carrageenan) were created and tested in order to obtain a stable biopolymer coating. Various techniques were used to characterize the resulting bioplastics, including Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC), contact angle measurements, and surface energy characterization. The influence of thermal and microbiological degradation on the properties of the blends was also investigated. From the analysis, it can be observed that the addition of agarose increased the hardness of the mixture by 27% compared to the control sample without the addition of polysaccharides. In addition, there was an increase in the surface energy (24%), softening point (15%), and glass transition temperature (14%) compared to the control sample. The addition of starch to the gelatine matrix increased the softening point by 15% and the glass transition temperature by 6%. After aging, both compounds showed an increase in hardness of 26% and a decrease in tensile strength of 60%. This offers an opportunity as application materials in the form of biopolymer coatings, dietary supplements, skin care products, short-term and single-contact decorative elements, food, medical, floriculture, and decorative industries. Full article

Seaweeds, rich in high-value polysaccharides with thickening/gelling properties (e.g., agar, carrageenan, and alginate), are extensively used in the food industry for texture customization and enhancement. However, conventional extraction methods for these hydrocolloids often involve potentially hazardous chemicals and long extraction times. In this study, three red seaweed species (Chondrus crispus, Gelidium Corneum, and Gracilaria gracilis) commercialized as food ingredients by local companies were chosen for their native gelling biopolymers, which were extracted using water-based methodologies (i.e., (1) hydration at room temperature; (2) stirring at 90 °C; and (3) centrifugation at 40 °C) for production of sustainable food gels. The potential use of these extracts as bioinks was assessed employing an extrusion-based 3D printer. The present work aimed to study the gelation process, taken place during printing, and assess the effectiveness of the selected green extraction method in producing gels. To improve the definition of the printed gel, two critical printing parameters were investigated: the addition of locust bean gum (LBG) at different concentrations (0, 0.5, 1, 1.5, 2, and 2.5%) and printing temperature (30, 40, 60, and 80 °C). Rheological results from a controlled-stress rheometer indicated that gels derived from G. corneum and G. gracilis exhibited a lower gel strength (lower G′ and G″) and excessive material spreading during deposition (lower viscosity) than C. crispus. Thus, G′ was around 5 and 70 times higher for C. crispus gels than for G. corneum and G. gracilis, respectively. When increasing LBG concentration (0.5 to 2.5% w/w) and lowering the printing temperature (80 to 30 °C), an enhanced gel matrix definition for G. corneum and G. gracilis gels was found. In contrast, gels from C. crispus demonstrated greater stability and were less influenced by these parameters, showcasing the potential of the seaweed to develop sustainable clean label food gels. Eventually, these results highlight the feasibility of using algal-based extracts obtained through a green procedure as bioinks where LBG was employed as a synergic ingredient. Full article

The market for electric vehicles and portable and wearable electronics is expanding rapidly. Lithium-ion batteries currently dominate the market, but concerns persist regarding cost and safety. Consequently, alternative battery chemistries are investigated, with zinc-ion batteries (ZIBs) emerging as promising candidates due to their favorable characteristics, including safety, cost-effectiveness, theoretical volumetric capacity, energy density, and ease of manufacturing. Hydrogel electrolytes stand out as advantageous for ZIBs compared to aqueous electrolytes. This is attributed to their potential application in flexible batteries for wearables and their beneficial impact in suppressing water-induced side reactions, zinc dendrite formation, electrode dissolution, and the risk of water leakage. The novelty of this review lies in highlighting the advancements in the design and synthesis of biopolymer hydrogel electrolytes in ZIBs over the past six years. Notable biopolymers include cellulose, carboxymethyl cellulose, chitosan, alginate, gelatin, agar, and gum. Also, double-network and triple-network hydrogel electrolytes have been developed where biopolymers were combined with synthetic polymers, in particular, polyacrylamide. Research efforts have primarily focused on enhancing the mechanical properties and ionic conductivity of hydrogel electrolytes. Additionally, there is a concerted emphasis on improving the electrochemical performance of semi-solid-state ZIBs. Moreover, some studies have delved into self-healing and adhesive properties, anti-freezing characteristics, and the multifunctionality of hydrogels. This review paper concludes with perspectives on potential future research directions. Full article

Agar is a hydrophilic biopolymer extracted from red seaweed. This phycocolloid consists of two components: agarose and agaropectin. In the present work, agar extracted from the invasive red seaweed Agarophyton vermiculophyllum was characterized using physical, chemical, and spectroscopic analyses to investigate the effect of alkaline pretreatment on agar properties. Two extraction conditions, native and alkali-pretreated agars, were comparatively studied. The native yield (28.4 ± 0.9%) was higher than that of the alkaline-pretreated agar (20.4 ± 0.8%). The alkali-pretreated agar showed higher gel strength (763.8 ± 57.0g cm⁻²), gelling (36.5 ± 0.9 °C), and melting (83.2 ± 0.6 °C) temperatures and increased 3,6-anhydrogalactose (26.2 ± 1.9%) and decreased sulfate contents (6.2 ± 0.8%) compared with native agar (gel strength: 204.8 ± 17.10g cm⁻², gelling temperature: 29.5 ± 0.9 °C, melting temperature: 73.4 ± 0.7 °C, 3,6-AG content: 13.8 ± 0.7%, sulfate content: 10.5 ± 0.5%). The alkaline pretreatment improved the agar’s gelling properties and significantly influenced its chemical properties. In view of the obtained results, A. vermiculophyllum might potentially be thought of as a viable source for the agar industry in Morocco, serving as a local source of agar. Full article

Food is humans’ main source of nickel intake, which is responsible for the prevalence of allergic contact dermatitis and other pathological afflictions. While robust, the classical methods for nickel detection—atomic absorption spectrometry and inductively coupled plasma mass spectrometry—are expensive and laborious; in contrast, modern methods that utilize sensors—of which most are electrochemical—have rapid run times, are cost-effective, and are easily assembled. Here, we describe the use of four biopolymers (alginate, agar, chitosan, and carrageenan) for receptor immobilization on biosensors to detect nickel ions and use an optimization approach with three biopolymer concentrations to assay analytical performance profiles. We measured the total performance of screen-printed carbon electrodes immobilized with the biopolymer–sensor combinations using cyclic voltammetry (CV). Voltammetric behavior favored the carrageenan biosensor, based on performance characteristics measured using CV, with sensitivities of 2.68 (for 1% biopolymer concentration) and 2.08 (for 0.5% biopolymer concentration). Our results indicated that among the four biopolymer combinations, carrageenan with urease affixed to screen-printed electrodes was effective at coupling for nickel detection. Full article