Search Results (55)

White mulberry (Morus alba L.) is a tree growing up to 15 m in height. It is a plant whose cultivation is historically associated with silk production. Mulberry leaves are the only food source of the mulberry silkworm caterpillars (Bombyx mori L.). The cultivation of this tree has recently gained renewed importance. Due to the content of numerous bioactive substances, mulberry is a valuable raw material for the food, pharmaceutical and herbal industries. This article presents the results of tests on pellets from 1-, 3- and 5-year-old branches, which are waste biomass remaining after pruning mulberry shrubs cultivated to obtain leaves to feed silkworms. Additionally, analyses of pellets from mulberry leaves were also carried out. For the specified mulberry biomass yield, analyses of chemical composition of mulberry biomass (branches and leaves) were carried out, and energy properties (heat of combustion and calorific value) and energy potential were calculated. The heat of combustion of pellet from mulberry branches was, on average, 19,266 MJ∙Mg⁻¹, and the calorific value was 17,726 MJ∙Mg⁻¹. The energy potential, on the other hand, was, on average, 159 GJ∙ha⁻¹ and 44 MWh∙ha⁻¹. The obtained results indicate the possibility of the effective use of mulberry branches after the annual pruning of bushes in plantations for energy purposes. Full article

In the silk production process, cocoons from Bombyx mori worm are degummed and separated from their components. This step generates large residual quantities of an aqueous solution containing various chemical substances, including sericin—a protein that, when discarded improperly, negatively impacts the environment. Sodium bicarbonate and coconut soap are commonly used in the degumming process. The phosphates in the soap and the sodium bicarbonate increase the biological oxygen demand (BOD) and chemical oxygen demand (COD), leading to water contamination. In this study, a Box–Behnken experimental design was used to maximize the extraction of sericin through a conventional extraction under chemical-free conditions. From a total of 45 experiments, the optimal extraction conditions were identified as a solid-to-liquid ratio of 1:20 w/v, a temperature of 120 °C, and 90 min of extraction time. Sericin yields ranged from 9% to 18%. Infrared spectroscopic characterization of the extracted sericin confirmed the presence of protein-specific functional groups and common interactions associated with β-sheet structures. Fractions of high molecular weight (50 kDa to 200 kDa), identified by means of Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) analysis, demonstrate the potential functionality of extracted sericin for the development of biopolymer films useful in biomedical and food industry applications. The optimized methodology is a good alternative to recycle the waste of sericulture chain for obtaining extracts enriched in sericin, as well as to promote the mechanization of artisanal production processes. Full article

Sericin, a natural glycoprotein constituting 20–30% of the silk cocoon, has emerged as a promising biomaterial due to its excellent biological properties, including biocompatibility, antioxidant properties and potential applications in regenerative medicine. The quality and the features of sericin are strongly dependent on the extraction and purification methods, which can employ mild conditions to preserve the molecular integrity of the protein or recovery techniques from waste streams produced during the industrial degumming processes. The silk industry prioritizes fiber yield over protein preservation, so often harsh alkaline conditions at high temperatures are adopted. These divergent approaches result in fundamentally different products with distinct molecular characteristics and functional capabilities. This review comprehensively examines the current technological approaches for sericin extraction techniques and for its recovery from textile industry waste, focusing on how these aspects affect the biological properties of the protein and the potential applications. Full article

In a world characterized by rapid industrialization and a growing population, plastic or polymeric waste handling has undergone significant transformations. Recycling has become a major strategy where silk sericin has great potential among recyclable polymers. This naturally occurring biopolymer is a sustainable and versatile material with a wide range of potential uses in biotechnology and sensing. Furthermore, preparing and studying new environmentally friendly functional polymers with attractive physicochemical properties can open new opportunities for developing next-generation materials and composites. Herein, we provide an overview of the advances in the research studies of silk sericin as a functional and eco-friendly material, considering its biocompatibility and unique physicochemical properties. The structure of silk sericin and the extraction procedures, considering the influence of preparation methods on its properties, are described. Sericin’s intrinsic properties, including its ability to crosslink with other polymers, its antioxidative capacity, and its biocompatibility, render it a versatile material for multifunctional applications across diverse fields. In biotechnology, the ability to blend sericin with other polymers enables the preparation of materials with varied morphologies, such as films and scaffolds, exhibiting enhanced mechanical strength and anti-inflammatory effects. This combination proves particularly advantageous in tissue engineering and wound healing. Furthermore, the augmentation of mechanical strength, coupled with the incorporation of plasticizers, makes sericin films suitable for the development of epidermal electrodes. Simultaneously, by precisely controlling hydration and permeability, the same material can be tailored for applications in packaging and the food industry. This work highlights the multidisciplinary and multifunctional nature of sericin, emphasizing its broad applicability. Full article

Synthetic and natural fibers are widely used in the textile industry. Natural fibers include cellulose-based materials like cotton, and regenerated fibers like viscose as well as protein-based fibers such as silk and wool. Synthetic fibers, on the other hand, include PET and polyamides (like nylon). Due to significant differences in their chemistry, distinct dyeing processes are required, each generating specific waste. For example, cellulose fibers exhibit chemical inertness toward dyes, necessitating chemical auxiliaries that contribute to wastewater contamination, whereas synthetic fibers are a major source of non-biodegradable microplastic emissions. Addressing the environmental impact of fiber processing requires a deep molecular-level understanding to enable informed decision-making. This manuscript emphasizes potential solutions, particularly through the biodegradation of textile materials and related chemical waste, aligning with the United Nations Sustainable Development Goal 6, which promotes clean water and sanitation. For instance, cost-effective methods using enzymes or microbes can aid in processing the fibers and their associated dyeing solutions while also addressing textile wastewater, which contains high concentrations of unreacted dyes, salts, and other highly water-soluble pollutants. This paper covers different aspects of fiber chemistry, dyeing, degradation mechanisms, and the chemical waste produced by the textile industry, while highlighting microbial-based strategies for waste mitigation. The integration of microbes not only offers a solution for managing large volumes of textile waste but also paves the way for sustainable technologies. Full article

Pineapple, extensively cultivated in tropical and subtropical regions, contains bromelain, a protein-digesting enzyme that is highly valued in the food and beverage industries. Pineapple residues from food processing retain these enzymes and can be repurposed for silk processing. This research utilized Smooth Cayenne pineapple juice as a degumming agent and its pulp as an adsorbent for dyeing effluent treatment. Pineapple juice, containing bromelain with a protease activity of 16.40 µg/mL·min, effectively removed 22% of sericin from raw silk using a liquid ratio of 30:1 at pH 7 and 60 °C for 60 min. Unlike alkaline degumming, which weakened silk fibers (maximum load 6.18 ± 1.56 N), pineapple juice-treated silk retained higher strength (maximum load 7.80 ± 1.32 N), offering a gentler alternative. The remaining pineapple pulp, after juice extraction, was processed into a porous adsorbent with a surface area of 3.63 m²/g and a pore size of 6.15 nm. This material absorbed acid dyes effectively at pH 5, the normal pH used in the acid dyeing of silk. Valorizing pineapple residues reduces chemical use, energy consumption, and environmental impact while lowering production costs and enhancing local resources. Full article

Global warming and climate change demand rapid and swift action in terms of reducing resource consumption, gas emissions, and waste generation. The textile industry is responsible for a large share of global pollution; therefore, to define a route to tackle part of the issue, a literature review on the current state of research in the field of recycling silk waste was conducted. The methods used to recover, process, and characterize silk waste fibers were summarized. The aim of this work was to investigate the possible applications of recycled silk waste in the field of composite materials for load bearing applications. In this sense, some prominent studies in the field of silk-based composites were reported, favoring thermoplastic materials for sustainability reasons. Studies on nonwoven silk waste fabrics were covered as well, finding an abundance of results but no applications as a reinforcement for composite materials. In a circular economy approach, we believe that the combination of nonwoven silk waste fabrics, thermoplastic polymers, and possibly hybridization with other fibers from sustainable sources could be beneficial and could lead to green and high-performance products. The aim of this work was to summarize the information available so far and help define a route in that direction. Full article

Synthesis of the photocatalysts with near-infrared light response usually involves upconversion materials or plasmon-assisted noble metals. Herein, NiTiO₃/TiO₂ was synthesized by using waste tobacco stem-silks as biotemplates and tetra-tert-butyl orthotitanate and nickel nitrate as precursors in a one-pot procedure. NiTiO₃(1.0)/TiO₂(TSS) with a mass percent of Ni 1.0% exhibited very high visible-light photocatalytic efficiency in photodegradation of tetracycline hydrochloride (TC), which is 8.0 and 2.3 times higher than TiO₂ prepared without templates and TiO₂(TSS) prepared without Ni, respectively. Interestingly, NiTiO₃(1.5)/TiO₂(TSS) even exhibited good activity under NIR light (λ = 840~850 nm) without upconversion materials or plasmon-assisted noble metals, which is 2.8 and 2.2 times than TiO₂ prepared without templates and TiO₂(TSS), respectively. The boosting photocatalytic activity has been shown to be attributed to efficient charge separation and transfer across a direct Z-scheme heterojunction between NiTiO₃ and TiO₂ and enhanced light-harvesting ability of special flaky structure reduplicated from tobacco stem-silks. This reported strategy provides a new idea for the multifunctional utilization of waste tobacco stem-silks and the synthesis of novel photocatalysts for the potential application in wastewater treatment. Full article

Many adsorbent materials are being studied for dye and oil removal from the environment. Bio-based materials such as silk are promising candidates due to their enhanced affinity for dyes and intrinsic hydrophobicity. This work extensively studies various silk textiles as dye and oil adsorbents. For comparison, we use electrospun fiber mats and hollow silk microparticle-treated silk fabrics. Our work is motivated by two factors: (i) massive amounts of silk waste is being discarded annually from textile factories, and (ii) the limited studies on the adsorption phenomena of pristine silk textiles. Based on our findings, 12 mg of silk filament yarn has a 90% methylene blue (MB) removal efficiency within 10 min of exposure for concentrations up to 100 ppm and exhibits adsorption capacities of 145 mg/g for 800 ppm concentrations. The adsorption kinetics obey a pseudo-second order, where the rate-controlling step is chemisorption, and isotherms follow the Langmuir model with homogenous monolayer adsorption. Furthermore, noil woven fabrics with contact angles of 140⁰ have oil adsorbent capacities that are double the fabric weight. Our work confirms that silk waste textiles are efficient and reusable bio-adsorbents for MB dye and oil removal, outperforming materials made with additional and energy-intensive techniques such as silk dissolution and electrospinning. Full article

The silkworm, Bombyx mori, is reared on a large scale, mainly for silk production. The waste from this silk production, like pupae, is underused. As an edible insect, B. mori is a good source of protein in human food and animal feed. In recent years, European legislation on the use of insects has evolved and a multitude of European companies have initiated the rearing of insects specifically for food and feed applications. Regarding animal feed, Commission Regulations (EU) 2021/1372 and 2021/1925 authorize eight insect species, including silkworm, as processed animal proteins for use in fish, pig, and poultry feed. The incorporation of edible insects into the human diet falls within Regulation (EU) No. 2015/2283 concerning novel foods. Implementation of authentication methods is imperative to ensure the conformity of the products. In the present study, we propose a specific real-time PCR method for the detection of silkworm (B. mori). The developed PCR test amplifies a 98 bp fragment of the cadherin gene. This gene is present in a single-copy per haploid genome, as demonstrated by experimental evidence. The qualitative method was successfully evaluated on the performance criteria of specificity, sensitivity, efficiency, robustness, and transferability. The applicability of the test was assessed on samples of B. mori from industry. Light microscopy and DNA metabarcoding approaches were used as a complement to genomic analysis as a means of providing authentication of the samples. Full article

Titanium dioxide (TiO₂) catalysts are primarily utilized under ultraviolet light, and their potential in industrial applications remains largely untapped. To address this issue, our study uses a one-pot impregnation method to prepare a series of In-TiO₂/TSS(X) (TSS, Tobacco stem silk. X, the molar ratio of In/Ti) catalysts. Among them, the degradation performance of the In-TiO₂/TSS(2.0) material increased from 13.8% for TiO₂ to an impressive 92.9%. By establishing a first-order kinetic model, it was determined that the degradation performance of the In-TiO₂/TSS(2.0) material surpassed that of TiO₂ by a factor of 24. Structural characterization revealed that the introduction of tobacco stem silk templates did not alter the crystal phase of TiO₂ and that the main component of the catalyst remained TiO₂. Not only that, an O–In structure formed on the surface of the TiO₂, leading to a significant increase in the material’s specific surface area. Furthermore, principle tests were conducted, revealing significant enhancements in its light absorption capacity, intensity, and photocurrent density. Through active species trapping experiments, it was observed that, in the photocatalytic degradation process of this catalyst series, holes (h⁺) played the primary role, while the hydroxyl ion (·OH) and superoxide ion (·O²⁻) acted as auxiliary species. Full article

Corn (Zea mays L.) is an essential gramineous food crop. Traditionally, corn wastes have primarily been used in feed, harmless processing, and industrial applications. Except for corn silk, these wastes have had limited medicinal uses. However, in recent years, scholars have increasingly studied the medicinal value of corn wastes, including corn silk, bracts, husks, stalks, leaves, and cobs. Hyperlipidemia, characterized by abnormal lipid and/or lipoprotein levels in the blood, is the most common form of dyslipidemia today. It is a significant risk factor for atherosclerosis and can lead to cardiovascular and cerebrovascular diseases if severe. According to the authors’ literature survey, corn wastes play a promising role in regulating glucose and lipid metabolism. This article reviews the mechanisms and material basis of six different corn wastes in regulating dyslipidemia, aiming to provide a foundation for the research and development of these substances. Full article

The bioplastics sector promotes environmentally friendly means of cutting down on the usage of fossil fuels, plastic waste, and environmental pollution. Plastic contamination has detrimental effects on both ecological systems and the global food supply. The approach we present here to resolve this issue involves the integration of sericin and gelatin, obtained from cocoon and fish waste, respectively, with nano-reinforced cellulose crystals, to develop a biodegradable and compostable plastic material. The use of cocoon and fish wastes for the extraction of sericin and gelatin presents an environmentally beneficial approach since it contributes to waste reduction. The sericin level found in silk cocoon waste was determined to be 28.08%, and the gelatin amount in fish waste was measured to be 58.25%. The inclusion of sericin and gelatin in bioplastics was accompanied by the incorporation of glycerol, vinegar, starch, sodium hydroxide, and other coloring agents. Fourier transform infrared (FTIR) examination of bioplastics revealed the presence of functional groups that corresponded to the sericin and gelatin components. The tensile strength of the bioplastic material was measured to be 27.64 MPa/psi, while its thickness varied between 0.072 and 0.316 mm. The results of burial experiments indicated that the bioplastic material had a degradation rate of 85% after 14 days. The invention exhibits potential as a viable alternative for packaging, containment, and disposable plastic materials. The use of this sustainable approach is recommended for the extraction of sericin and gelatin from silk cocoons and fish waste, with the intention of using them as raw materials for bioplastic production. Full article

The various wastes generated by silkworm silk textiles that are no longer in use are increasing, which is causing considerable waste and contamination. This issue has attracted widespread attention in countries that use a lot of silk. Therefore, enhancing the mechanical properties of regenerated silk fibroin (RSF) and enriching the function of silk are important directions to expand the comprehensive utilization of silk products. In this paper, the preparation of RSF/Al₂O₃ nanoparticles (NPs) hybrid fiber with different Al₂O₃ NPs contents by wet spinning and its novel performance are reported. It was found that the RSF/Al₂O₃ NPs hybrid fiber was a multifunctional fiber material with thermal insulation and UV resistance. Natural light tests showed that the temperature rise rate of RSF/Al₂O₃ NPs hybrid fibers was slower than that of RSF fibers, and the average temperature rose from 29.1 °C to about 35.4 °C in 15 min, while RSF fibers could rise to about 40.1 °C. UV absorption tests showed that the hybrid fiber was resistant to UV radiation. Furthermore, the addition of Al₂O₃ NPs may improve the mechanical properties of the hybrid fibers. This was because the blending of Al₂O₃ NPs promoted the self-assembly of β-sheets in the RSF reaction mixture in a dose-dependent manner, which was manifested as the RSF/Al₂O₃ NPs hybrid fibers had more β-sheets, crystallinity, and a smaller crystal size. In addition, RSF/Al₂O₃ NPs hybrid fibers had good biocompatibility and durability in micro-alkaline sweat environments. The above performance makes the RSF/Al₂O₃ NPs hybrid fibers promising candidates for application in heat-insulating and UV-resistant fabrics as well as military clothing. Full article

In the first half of the twentieth century, scientific communities worldwide endeavored to diminish dependence on expensive and scarce animal fibers like wool and silk. Their efforts focused on developing regenerated protein fibers, including soy, zein, and casein, to provide comparable benefits to natural protein fibers, such as lustrous appearance, warmth, and a soft feel. The popularity and cost-effectiveness of mass-produced petroleum-based synthetic polymer fibers during World War II diminished interest in developing soy protein fiber. Realizing the ecological degradation caused by fossil fuels and their derived products, a renewed drive exists to explore bio-based waste materials like soy protein. As a fast-growing crop, soy provides abundant byproducts with opportunities for waste valorization. The soybean oil extraction process produces soy protein as a byproduct, which is a highly tunable biopolymer. Various functional groups within the soy protein structure enable it to acquire different valuable properties. This review critically examines scholarly publications addressing soy protein fiber developmental history, soy protein microstructure modification methods, and soy protein fiber spinning technologies. Additionally, we provide our scientific-based views relevant to overcoming the limitations of previous work and share prospects to make soy protein byproducts viable textile fibers. Full article