Preparation and characterization of microcrystalline cellulose (MCC) from tea waste

Extraction and characterization of microcrystalline cellulose from carrot pomace using green pretreatment technologies

In this study, microcrystalline cellulose (MCC) from carrot pomace, which is a byproduct of the carrot process, was produced. The Response Surface Methodology optimized the effectiveness of autoclaving & ultrasonic pretreatments (AUP) in MCC extraction with a D-optimal design. The yield of AUP was 36.62 % at the optimum point; at the conventional acid hydrolysis method, it was 31.40 %. AUP-derived MCC demonstrated superior rheological properties, including water holding capacity (4.58 g H₂O/g MCC) and oil adsorption capacity (2.94 g oil/g MCC), comparable to commercial MCC. Characterization analyses revealed that the AUP-derived MCC had high crystallinity, thermal stability, and a short-fibered morphology, confirmed by FTIR, SEM, TGA, and XRD. Utilizing carrot pomace reduces agricultural waste while providing a valuable dietary fiber source (87.94 % insoluble fiber). This study highlights MCC production from carrot pomace using AUP offers an economically and environmentally viable alternative, with potential applications in food, pharmaceutical, and cosmetic industries.

Synergistic enhancement of high-barrier polylactic acid packaging materials by various morphological carbonized cellulose nanocrystals

The environmental challenges linked to petroleum-based polymers have accelerated the search for alternative materials like polylactic acid (PLA). Diverse nanofillers, ranging from inorganic to organic and hybrid inorganic/organic varieties, are employed to bolster PLA performance. Yet, non-synergistic nanofillers often underperform due to inadequate dispersion and singular functionality within the PLA matrix. This work introduces carbonized cellulose nanocrystals (GCNC) with rod-like (R-GCNC) and spherical structures (S-GCNC), as synergistic reinforcements for PLA matrix. Unlike traditional nanofillers, the highly graphitized carbon layer on GCNC effectively mitigates CNC agglomeration while preserving cellulose morphology, fostering improved interfacial interactions and hydrogen bonding within PLA matrix. Moreover, GCNC acts as a nucleating agent, boosting the crystallization rate of PLA and enhancing its mechanical properties. Remarkable synergistic reinforcing effects of GCNC on PLA performances were observed. Particularly, the tensile strength of R-GCNC 5 % and S-GCNC 5 % composites surged by 93 % and 76 %, elongation at break increased by 29.4 % and 33.3 %, Young's modulus rose by 37 % and 18 %, and cold crystallization temperature decreased by 11.5 °C and 12.9 °C. Additionally, the GCNC/PLA composites exhibited exceptional thermal stability, UV resistance, and water vapor permeability reduced by 46 % for R-GCNC, and 35 % for S-GCNC, making them promising for industrial and sustainable packaging.

The compressive resilience and shrinkage resistance properties of poly (butylene adipate-co-terephthalate) microcellular composite foams reinforced by functionalized microcrystalline cellulose

In this study, microcrystalline cellulose (MCC) modified with triethoxyvinylsilane (T-MCC) on compressive resilience and shrinkage resistance properties of microcellular composite foams based on poly (butylene adipate-co-terephthalate) (PBAT) were reported. It was found that the modification of MCC (T-MCC) with triethoxyvinylsilane could enhance the dispersion of MCC in the PBAT matrix and their compatibility. The modified microcrystalline cellulose can be embedded in the foam system as a "skeleton", interconnecting with adjacent cells to form the unique bridge-shell structure, contributing to a complete structure and enhancing the mechanical properties of foamed plastics. The complementary techniques of filling and crosslinking to produce foam with good compression elasticity and shrinkage resistance, which can increase its application, reduce the cost. Ultimately, PBAT/30T-MCC foam with 16.00 um cell size was successfully obtained, with the cell density as high as 2.18 × 109 cells/cm3 and shrinkage rate of less than 3.6 %, and the compressive strength and resilience of the foam were as high as 55.1 KPa and 90.1 %, respectively, after ten loaded-unloaded compression tests. This study provides a theoretical basis for the design and development of PBAT composite foams with low cost, high shrinkage resistance, and high compressive resilience.

All-cellulose resin for 3D printing hydrogels via digital light processing (DLP)

3D printing has emerged as a transformative technology in sustainable manufacturing, enabling rapid prototyping, minimizing material waste, and reducing the carbon footprint associated with traditional methods. However, their reliance on fossil-based materials limits their broad application. This study presents a novel approach for developing a single-component, fully cellulosic, natural-based resin for 3D printing hydrogels using digital light processing (DLP). Cellulose was dissolved in an aqueous alkali/urea system and modified to obtain photopolymerizable derivatives. Two cellulose sources were used: Avicel® and cellulose pulp obtained from an industrial process. The single-polymer resins produced dimensionally stable, free-standing 3D objects with good resolution and shape fidelity. Despite the low polymer concentration (2.5 and 5 wt%), the cellulose resins exhibited fast curing kinetics, producing hydrogels with good mechanical properties, capable of withstanding compressive stress up to 135 kPa. Additionally, the printed hydrogels absorbed and retained large amounts of water (up to 427 %), while maintaining their shape and integrity in acidic and alkaline media. The hydrogels were stable to hydrolytic degradation, maintained their shape for up to four weeks, and were cytocompatible with fibroblast cells, indicating their potential for biomedical applications.

Preparation and characterization of microcrystalline cellulose from rice bran

BACKGROUND

Rice bran, a by-product of rice processing, has not been fully utilized except for the small amount used for raising animals. The raw material source requirements of microcrystalline cellulose are becoming increasingly extensive. However, the characteristics of preparing microcrystalline cellulose from rice bran have not been reported, which limits the application of rice bran.

RESULTS

Microcrystalline cellulose was obtained from rice bran by alkali treatment, delignification, bleaching and acid hydrolysis. The morphology, particle size distribution, degree of polymerization, crystallinity, and thermal stability of rice bran microcrystalline cellulose were analyzed. The chemical compositions, scanning electron microscopy and Fourier-transform infrared analysis for rice bran microcrystalline cellulose showed that the lignin and hemicellulose were successfully removed from the rice bran fiber matrix. The morphology of rice bran microcrystalline cellulose was shown to be of a short rod-shaped porous structure with an average diameter of 65.3 μm. The polymerization degree of rice bran microcrystalline cellulose was 150. The X-ray diffraction pattern of rice bran microcrystalline cellulose showed the characteristic peak of natural cellulose (type I), and its crystallization index was 71%. The rice bran microcrystalline cellulose may be used in biological composites with temperatures between 150 °C and 250 °C.

CONCLUSION

These results suggest the feasibility of using rice bran as a low-price source of microcrystalline cellulose. © 2024 Society of Chemical Industry.

Nonlinear Dynamic Mechanical and Impact Performance Assessment of Epoxy and Microcrystalline Cellulose-Reinforced Epoxy

This study focusses on imrpoving the mechanical performance of epoxy resin by reinforcing it with microcrystalline cellulose (MCC). Epoxy composites with varying MCC mass fractions (0.5%, 1%, 1.5%, and 2%) are prepared and characterised to assess the influence of MCC on strain-rate-dependent flexural properties, impact resistance, and nonlinear viscoelastic behaviour. Three-point bending tests at different strain rates reveal that MCC notably increases the flexural strength and leads to nonlinear mechanical behaviour. It is shown that stiffness, strength and elongation at break increase with rising MCC content. Charpy impact tests show improved energy absorption and toughness, while Dynamic Mechanical Analysis (DMA) demonstrates that the materials prepared exhibit increased storage modulus and improved damping across a frequency range. These results indicate that MCC serves as an effective bio-based reinforcement, significantly boosting the strength and toughness of epoxy composites. The findings contribute to the development of sustainable, high-performance materials for advanced engineering applications.

Recent advances review in tea waste: High-value applications, processing technology, and value-added products

Tea waste (TW) includes pruned tea tree branches, discarded summer and fall teas, buds and wastes from the tea making process, as well as residues remaining after tea preparation. Effective utilization and proper management of TW is essential to increase the economic value of the tea industry. Through effective utilization of tea waste, products such as activated carbon, biochar, composite membranes, and metal nanoparticle composites can be produced and successfully applied in the fields of fuel production, composting, preservation, and heavy metal adsorption. Comprehensive utilization of tea waste is an effective and sustainable strategy to improve the economic efficiency of the tea industry and can be applied in various fields such as energy production, energy storage and pharmaceuticals. This study reviews recent advances in the strategic utilization of TW, including its processing, conversion technologies and high value products obtained, provides insights into the potential applications of tea waste in the plant, animal and environmental sectors, summarizes the effective applications of tea waste for energy and environmental sustainability, and discusses the effectiveness, variability, advantages and disadvantages of different processing and thermochemical conversion technologies. In addition, the advantages and disadvantages of producing new products from tea wastes and their derivatives are analyzed, and recommendations for future development of high-value products to improve the efficiency and economic value of tea by-products are presented.

A review of valorization of agricultural waste for the synthesis of cellulose membranes: Separation of organic, inorganic, and microbial pollutants

Agricultural waste presents a significant environmental challenge due to improper disposal and management practices, contributing to soil degradation, biodiversity loss, and pollution of water and air resources. To address these issues, there is a growing emphasis on the valorization of agricultural waste. Cellulose, a major component of agricultural waste, offers promising opportunities for resource utilization due to its unique properties, including biodegradability, biocompatibility, and renewability. Thus, this review explored various types of agricultural waste, their chemical composition, and pretreatment methods for cellulose extraction. It also highlights the significance of rice straw, sugarcane bagasse, and other agricultural residues as cellulose-rich resources. Among the various membrane fabrication techniques, phase inversion is highly effective for creating porous membranes with controlled thickness and uniformity, while electrospinning produces nanofibrous membranes with high surface area and exceptional mechanical properties. The review further explores the separation of pollutants including using cellulose membranes, demonstrating their potential in environmental remediation. Hence, by valorizing agricultural residues into functional materials, this approach addresses the challenge of agricultural waste management and contributes to the development of innovative solutions for pollution control and water treatment.

Extraction of microcrystalline cellulose from Ficus benghalensis leaf and its characterization

Microcrystalline cellulose (MCC) is a crucial component in various industries, including pharmaceuticals, culinary, and cosmetics. The growing demand for MCC has spurred research into extraction methods. This study focused on extracting MCC from Ficus benghalensis using acid hydrolysis to convert the alpha-cellulose content of its leaves into MCC. The solvent used in this process was recyclable for further use. The extracted MCC was characterized by its physicochemical properties, including density, yield percentage, and structural characteristics. The yield was approximately 39.68 %, and the density was low at 1.518 g/cm3, making it suitable for filler applications. Fourier transform spectroscopy and UV-visible analysis identified functional groups of cellulose. X-ray diffraction analysis revealed a crystallite size of 1.560 nm and a crystallinity index of 66.43 %, indicating suitability for related applications. ImageJ determined a mean particle size of 36.545 μm, while scanning electron microscopy showed distinct surface orientations. Atomic force microscopy revealed surface roughness, root mean square, ten-point average roughness, skewness, and kurtosis. Elemental analysis indicated high concentrations of carbon (20.1 %) and oxygen (34 %). Based on these physicochemical features, the extracted MCC could be a valuable source for applications such as filler in reinforcement technology and coating material in pharmaceutical products.

Development of starch-cellulose composite films with antimicrobial potential

This study explored the structure and performance of starch-based antibacterial films reinforced with black tea cellulose nanocrystals (BT-CNCs). The optimal addition amount of BT-CNCs is 5 % (w/w Starch). This nanocrystal-infused film, incorporating chitosan (CS), ε-polylysine (ε-PL), and zinc oxide nanoparticles (ZnONP) as antibacterial agents, exhibited a smooth, continuous surface. The addition of BT-CNCs and antibacterial agents did not change the group characteristic peaks of the film, but changed the crystallinity slightly. The films, namely St, St/CNCs, St/CNCs/CS, and St/CNCs/ε-P, maintained high light transmittance (above 80 %), except for the St/CNCs/ZnONP film, which effectively shielded UV radiation. The combined use of antibacterial agents and BT-CNCs enhanced the water and oxygen barrier properties of the film. Notably, the St/CNCs/CS film exhibited the lowest solubility (17.74 % ± 0.36) and the highest tensile strength (14.23 ± 0.16 MPa). The antibacterial efficacy of the films decreased in the order of St/CNCs/ZnONP, St/CNCs/ε-PL, and St/CNCs/CS, with a more pronounced inhibitory effect on E. coli compared to S. aureus. This study marries natural waste recycling with cutting-edge food packaging technology, setting a new benchmark for the development of sustainable packaging materials.

Preparation and characterization of Baijiu Jiuzao cellulose nanofibers-kafirin composite bio-film with excellent physical properties

Jiuzao is the main solid by-products of Baijiu industry, which contain a high amount of underutilized cellulose and proteins. In recent years, cellulose nanofibers mixed with proteins to prepare biodegradable bio-based film materials have received widespread attention. In this study, we propose a novel method to simultaneously extract kafirin and cellulose from strong-flavor type of Jiuzao, and modify cellulose to prepare cellulose nanofibers by the TEMPO (2,2,6,6-tetramethylpiperidine-1-oxide) oxidation-pressure homogenization technique, and finally mix kafirin with cellulose nanofibers to prepare a new biodegradable bio-based composite film. Based on the analysis of one-way and response surface experiments, the highest purity of cellulose was 82.04 %. During cellulose oxidation, when NaClO was added at 25 mmol/g, cellulose nanofibers have a particle size of 80-120 nm, a crystallinity of 65.8°. Finally, kafirin and cellulose nanofibers were mixed to prepare films. The results showed that when cellulose nanofibers were added at 1 %, the film surface was smooth, the light transmittance was 60.8 %, and the tensile strength was 9.17 MPa at maximum, which was 104 % higher than pure protein film. The contact angle was 34.3°. This paper provides new ideas and theoretical basis for preparing biodegradable bio-based composite film materials, and improves the added value of Jiuzao.

Obtention and Characterization of Microcrystalline Cellulose from Industrial Melon Residues Following a Biorefinery Approach

Residual melon by-products were explored for the first time as a bioresource of microcrystalline cellulose (MCC) obtention. Two alkaline extraction methods were employed, the traditional (4.5% NaOH, 2 h, 80 °C) and a thermo-alkaline in the autoclave (2% NaOH, 1 h, 100 °C), obtaining a yield of MCC ranging from 4.76 to 9.15% and 2.32 to 3.29%, respectively. The final MCCs were characterized for their chemical groups by Fourier-transform infrared spectroscopy (FTIR), crystallinity with X-ray diffraction, and morphology analyzed by scanning electron microscope (SEM). FTIR spectra showed that the traditional protocol allows for a more effective hemicellulose and lignin removal from the melon residues than the thermo-alkaline process. The degree of crystallinity of MCC ranged from 51.51 to 61.94% and 54.80 to 55.07% for the thermo-alkaline and traditional processes, respectively. The peaks detected in X-ray diffraction patterns indicated the presence of Type I cellulose. SEM analysis revealed microcrystals with rough surfaces and great porosity, which could remark their high-water absorption capacity and drug-carrier capacities. Thus, these findings could respond to the need to valorize industrial melon by-products as raw materials for MCC obtention with potential applications as biodegradable materials.

Sustainable microcrystalline cellulose extracted from biowaste Albezia lebeck L. leaves: Biomass exfoliation and physicochemical characterization

There is a focus on sustainability when manufacturing materials. Utilizing biobased materials and replacing fossil-based products is the main research focus. Bio-composite materials are applied to packaging, filler coatings, and pharmaceuticals. Here, we used the leaves of the agro-waste plant Albizia lebeck L. to extract cellulose. Chemical treatment causing strong acid hydrolysis successfully extracted the cellulose content from the leaves. The cellulose obtained was then strengthened with polylactic acid to make a biobased film for future applications. Fourier transform spectroscopy, scanning electron microscopy, thermal analysis, particle size analysis, visible UV and elemental analysis were all used to characterize the extracted cellulose. SEM and mechanical property analysis were used to check and describe the quality of the reinforced biofilm. The greatest cellulose yield from this raw material was 50.2%. The crystallinity index and crystallite size (CI 70.3% and CS 11.29 nm) were high in the extracted cellulose. The TG (DTG) curve analysis derivative revealed cellulose particle breakdown was initiated around 305.2°C and can endure temperatures up to 600°C. Biofilms reinforced with polylactic acid cellulose (1, 2, 3, and 5% by weight %) exhibited a smooth and parallel surface. As the filler concentration increased, minor agglomeration occurred. The tensile strength of pure polylactic acid (PLA) (34.72 MPa) was extended up to 38.91 MPa for 5% filler. Similarly, Young's modulus also increased to 5.24 MPa. However, the elongation break decreases with the increase of filler content, and the least value of decrease is 7.5 MPa. Concerning prospective implementations, it is expected that the biobased film and cellulose particles will prove to be more functional.

Comprehensive characterization of microcrystalline cellulose from lemon grass (Cymbopogan citratus) oil extraction agro-industrial waste for cementitious composites applications

Presently, the construction industry demands components that are exceptionally strong and long-lasting. The initial important construction material is concrete, which contains between 1 % and 2 % of air voids. The structural damage caused by water that enters through the air spaces are improved with filler material. Chemical filler materials are environmentally harmful; therefore, eco-friendly materials are selected for this study. The environmentally benign character of agro-waste byproduct usage is a driving factor in the field of research. Numerous uses can be found for waste materials, especially after they have been repurposed. We used a byproduct of an essential oil extraction company, an extract made from the leaves of lemon grass (Cymbopogan citrus), in our research. Alkalization, slow pyrolysis, acid hydrolysis, and bleaching are only some of the chemical treatments that could be used to easily extract microcrystalline cellulose from the discarded waste material. In our study the chemicals used are mild harmful to the environment and a surface reactant (linear alkyl benzene sulfonic acid) is utilised to bleach and purify the microcrystalline cellulose. Thermal analysis, scanning electron microscopy, transmission electron microscopy and Fourier transform spectroscopy were all used to learn more about the cellulose that had been extracted. The extracted cellulose powder comprises a high crystallinity index (68.14 %) and low crystallite size (5.13 nm) found using X-ray diffraction analysis. The smooth and porous surface is observable in scanning electron microscope analysis. The Differential scanning calorimeter curve shows the highest degradation temperature at 218.16 °C. The micro sized particles mostly range between 100 and 120 μm and are found using ImageJ. The surface roughness and permissible skewness of cellulose particles were examined using atomic force microscopy. The density of extracted cellulose is 1.092 g/cm3. The microcrystalline cellulose yield % was notably maximum (40.45 %). This cellulose was introduced in a M30 grade cement concrete as fillers up to 5 % by the weight of cement. The fresh and mechanical properties of the concrete was found to get improved with the addition of cellulose up to 3 %. As a result, the characteristics of cellulose boost its utility within the construction sector.

Microcrystalline cellulose from soybean hull as an excipient in solid dosage forms: Preparation, powder characterization, and tableting properties

Microcrystalline cellulose (MCC) is one of the essential functional excipients in the formulation of tablets. The need for cheaper MCC sources has drawn significant attention to exploring renewable sources. In this study, MCC was produced from soybean hull (SBH), the primary by-product of the soy industry, using a novel, simplified, and cost-effective approach. Various characterization techniques were used to study the physicochemical properties and micromeritics of the SBH-based MCC powders and compare them to those of the commercial Avicel PH-101. SBH MCCs had a larger particle size, a broader particle size distribution, a higher degree of polymerization, a higher degree of crystallinity, better thermal stability, and slightly superior flowability and compressibility than Avicel PH-101. The tableting blends (containing 60 % MCC) were prepared, and the post-compression out-of-die Heckel analysis showed that formulations with aggregated SBH MCCs were less ductile than those made with Avicel PH-101, resulting in a lower porosity (better compressibility) of the latter at higher compression pressures. The hardness values for all formulations were above 6 kg, with higher values for those made with Avicel PH-101. The lubricant sensitivity was lower for SBH MCCs. All tablets made using developed formulations showed very low friability (<0.1 %) and short disintegration times (<90 s), making them well-suited candidates for manufacturing orally disintegrating tablets (ODTs).

Unveiling structure and performance of tea-derived cellulose nanocrystals

In this study, cellulose was extracted from black tea residues to produce black tea cellulose nanocrystals (BT-CNCs) using an optimized acid hydrolysis method. The structure and performance of BT-CNCs were evaluated. The results showed that the optimal conditions for acidolysis of BT-CNCs included a sulfuric acid concentration of 64 %, a solid-liquid ratio of 1:18 (w/v), a hydrolysis temperature of 45 °C, and a hydrolysis time of 50 min. The optimization process resulted in a 44.8 % increase in the yield of BT-CNCs, which exhibited a crystallinity of 68.57 % and were characterized by the typical cellulose I structure. The diameters of the particles range from 5 to 45 nm, and they exhibit aggregation behavior. Notably, BT-CNCs demonstrated excellent storage stability, and the Tyndall effect occurred when exposed to a single beam of light. Although the thermal stability of BT-CNCs decreased, their primary thermal degradation temperature remained above 200 °C. The colloidal nature of BT-CNCs was identified as a non-Newtonian fluid with "shear thinning" behavior. This study introduces a novel method to convert tea waste into BT-CNCs, increasing the yield of BT-CNCs and enhancing waste utilization. BT-CNCs hold promise for application in reinforced composites, offering substantial industrial value.

Extraction and characterization of microcrystalline cellulose from Vachellia nilotica plant leaves: A biomass waste to wealth approach

Biobased waste utilization is an intriguing area of research and an ecologically conscious approach. Plant-based materials can be used to render cellulose, which is an eco-friendly material that can be used in numerous aspects. In the current investigation, cellulose was extracted from the leaves of the Vachellia nilotica plant via acid hydrolysis. The application of this research is specifically directed toward the utilization of undesirable plant sources. To validate the extracted cellulose, FT-IR spectroscopy was applied. The cellulose was measured to have a density of 1.234 g/cm3. The crystallinity index (58.93%) and crystallinity size (11.56 nm) of cellulose are evaluated using X-ray diffraction spectroscopy analysis. The highest degradation temperature (320.8°C) was observed using thermogravimetry and differential scanning calorimetry curve analysis. The analysis of particle size was conducted utilizing images captured by scanning electron microscopy. Particle size of less than 30 μm was found and they exhibit non-uniform orientation. Additionally, atomic force microscopy analysis shows an improved average surface roughness (Ra), which increases the possibility of using extracted cellulose as reinforcement in biofilms.

Cellulose separation from ramie bone by one step process with green hydrogen peroxide-citric acid

Ramie bone (RB), an agricultural waste generated in the textile industry, is a vastly productive renewable natural resource with the potential to be used as a source of cellulose. In this study, ramie bone cellulose (RB-CE) was obtained in one step using a simple and ecologically friendly hydrogen peroxide-citric acid (HPCA) treatment procedure that avoided the use of halogenated reagents and strong acids while also streamlining the treatment processes. Various analytical methods were used to investigate the chemical composition and structure, crystallinity, morphology, thermal properties, surface area and hydration properties of cellulose separated at different treatment temperatures. HPCA successfully removed lignin and hemicellulose from RB, according to chemical composition analysis and FTIR. RB-CE had a type I cellulose crystal structure, and the crystallinity improved with increasing treatment temperature, reaching 72.51 % for RB-CE90. The RB-CE showed good thermal stability with degradation temperatures ranging from 294.2 °C to 319.1 °C. Furthermore, RB-CE had a high water/oil binding capacity, with RB-CE90 having WHC and OBC of 9.68 g/g and 7.24 g/g, respectively. The current work serves as a model for the environmentally friendly and convenient extraction of cellulose from biomass, and the cellulose obtained can be employed in the field of food and composite materials.

Valorization of tea waste: Composition, bioactivity, extraction methods, and utilization

Tea is the most consumed beverage worldwide and has many health effects. Although there are many different types of tea, black tea and green tea comprise 98% of total tea production in the world. Tea waste production consists of withering, crushing, fermentation, drying and finally packaging processes. All of the waste generated during this production line is called tea waste. Tea production results in a significant amount of waste that cannot be effectively used for value creation. This waste contains many different components including protein, fiber, caffeine, and polyphenols. Due to its rich composition, it can be revalorized for different purposes. In this study, the general composition and bioactive compounds of tea waste were reviewed. Despite the fact that there have been few studies on the bioactivity of tea waste, those studies have also been discussed. The extraction techniques that are used to separate the compounds in the waste are also covered. It has been indicated that these valuable compounds, which can be separated from tea wastes by extraction methods, have the potential to be used for different purposes, such as biogas production, functional foods, food additives, silages, soluble packaging materials, and adsorbents. Although there are some studies on the revalorization of tea waste, new studies on the extraction of bioactive compounds are necessary to improve its utilization potential.

Characterization of microcrystalline cellulose prepared from long and short fibers and its application in ibuprofen tablets

As a bio-based material, microcrystalline cellulose (MCC) has been applied in many fields including pharmaceuticals, foods, and cosmetics in recent years. However, traditional preparation methods of MCC are facing many challenges due to economic and eco-environmental issues. In this study, softwood dissolved pulp was sieved to long fiber (LF) and short fiber (SF), and subsequently to prepare LF-MCC and SF-MCC by hydrochloric acid hydrolysis at different acid dosages (3-7 wt%), reaction times (30-90 min), and temperatures (75-95 °C). The as-obtained MCC products were compared in terms of morphology, size, crystallinity, and chemical structure. The results indicated that the crystallinity and yield of LF-MCC were high, with maximum values of 78.41 % and 98.68 %, respectively. The particle size distribution of SF-MCC was more uniform in the range of 20-80 μm, with a maximum of 59.44 % at 20-80 μm occupancy proportion. Moreover, SF-MCC had a typical rod-like shape and larger surface area as well as better thermal behavior than LF-MCC. When LF-MCC and SF-MCC were used as fillers in the production of ibuprofen tablets, the tablets added with LF-MCC exhibited higher hardness, friability, dissolution rate, and shorter disintegration time. Therefore, this work is very beneficial for the preparation and application of MCC.

Comparative study on liquid versus gas phase hydrochloric acid hydrolysis for microcrystalline cellulose isolation from sugarcane bagasse

Microcrystalline cellulose (MCC) was successfully synthesized from sugarcane bagasse using a rapid, low-temperature hydrochloric acid (HCl) gas treatment. The primary aim was to develop an energy-efficient "green" cellulose extraction process. Response surface methodology optimized the liquid-phase hydrolysis conditions to 3.3 % HCl at 117 °C for 127 min to obtain MCC with 350 degree of polymerization. An alternative gas-phase approach utilizing gaseous HCl diluted in hot 40 °C air was proposed to accelerate MCC production. The cellulose pulp was moistened to 15-18 % moisture content and then exposed to HCl gas, which was absorbed by the moisture in the cellulose fibers to generate a highly concentrated acidic solution that hydrolyzed the cellulose. The cellulose pulp was isolated from depithed bagasse through soda pulping, multistage bleaching and cold alkali purification. Hydrolysis was conducted by saturating the moist cellulose fibers with gaseous HCl mixed with hot air. Extensive analytical characterization using FT-IR, XRD, SEM, TGA, DSC, particle size, and porosity analyses verified comparable physicochemical attributes between MCC samples prepared via liquid and gas phase methods. The gas-produced MCC revealed 85% crystallinity, 71 Å crystallite dimensions, and thermally stable rod-shaped morphology with an average diameter below 200 μm. The similar material properties validate the proposed gas-based technique as an equally effective yet more energy-efficient alternative to conventional aqueous acid hydrolysis for fabricating highly pure MCC powders from lignocellulose. This sustainable approach enables the value-addition of sugarcane bagasse agro-industrial residue into cellulosic nanomaterials for wide-ranging industrial applications. In summary, the key achievements of this work are rapid MCC production under mild temperatures using HCl gas, optimization of liquid phase hydrolysis, successful demonstration of gas phase method, and extensive characterization verifying equivalence between both protocols. The gas methodology offers a greener cellulose extraction process from biomass.

Isolation and characterization of microcrystalline cellulose from an agro-waste tamarind (Tamarindus indica) seeds and its suitability investigation for biofilm formulation

The exploration of potential bio-fillers for bio-film application is a promising approach to ensure biodegradable, eco-friendly, good-quality materials with high-performance applications. This is a comprehensive study executed to establish the utility of an agro-waste Tamarindus indica seeds for microcrystalline cellulose production and to assess its feasibility for biofilm fabrication. The extraction was carried out through consecutive chemical-mediated alkalization, acid hydrolysis and bleaching. The isolated microcrystalline cellulose from Tamarindus indica seeds (TSMCC) was characterized through chemical, thermal and morphological characterization to validate the cellulose contribution, thermal resistance, and compatibility of the material. The physical parameters as density and yield percentage were assessed to evaluate its light-weight utility and economic productivity. These examinations revealed that TSMCC has good specific properties such as high cellulose content (90.57 %), average density (1.561 g/cm3), feasible average roughness (12.161 nm), desired particle size (60.40 ± 21.10 μm), good crystallinity (CI-77.6 %) and thermal stability (up to 230 °C); which are worthwhile to consider TSMCC for bio-film formulation. Subsequently, bio-films were formulated by reinforcing TSMCC in polylactic acid (PLA) matrix and the mechanical properties of the bio-films were then studied to establish the efficacy of TSMCC. It is revealed that the properties of pure PLA film increased after being incorporated with TSMCC, where 5 %TSMCC addition showed greater impact on crystalline index (26.16 % to 39.62 %), thermal stability (333oc to 389 °C), tensile strength (36.11 ± 2.90 MPa to 40.22 ± 3.22 MPa) and modulus (2.62 ± 0.55GPa to 4.15 ± 0.53GPa). In light of all promising features, 5 % TSMCC is recommended as a potential filler reinforcement for the groundwork of good quality bio-films for active packaging applications in future.

Extraction methods, physiological activities and high value applications of tea residue and its active components: a review

Tea is a traditional plant beverage originating from China as one of the most popular beverages worldwide, which has been an important companion in modern society. Nevertheless, as the waste after tea processing, tea residues from agriculture, industry and kitchen waste are discarded in large quantities, resulting in waste of resources and environmental pollution. In recent years, the comprehensive utilization of tea residue resources has attracted people's attention. The bioactive components remaining in tea residues demonstrate a variety of health benefits and can be recycled using advanced extraction processes. Furthermore, researchers have been devoted to converting tea residues into derivatives such as biosorbents, agricultural compost, and animal feeds through thermochemical techniques and biotechnology. This review summarized the chemical composition and physiological activities of bioactive components from tea residue. The extraction methods of bioactive components in tea residue were elucidated and the main high-value applications of tea residues were proposed. On this basis, the utilization of tea residues can be developed from a single way to a multi-channel or cascade way to improve its economic efficiency. Novel applications of tea residues in different fields, including food development, environmental remediation, energy production and composite materials, are of far-reaching significance. This review aims to provide new insights into developing the utilization of tea residue using a comprehensive strategy and exploring the mechanism of active components from tea residue on human health and their potential applications in different areas.HighlightsThe composition and function of tea residue active components were introduced.The extraction methods of active components from tea residue were proposed.The main high-value applications of tea residues were summarized.The current limitations and future directions of tea residue utilization were concluded.

Obtaining Cellulose Nanocrystals from Olive Tree Pruning Waste and Evaluation of Their Influence as a Reinforcement on Biocomposites

The objective of this work is to improve the mechanical properties of polylactic acid (PLA) by incorporating cellulose nanocrystals (CNC) previously obtained from a cellulose pulp extracted from olive tree pruning (OTP) waste. Composites were manufactured by melt processing and injection moulding to evaluate the effect of the introduction of CNC with conventional manufacturing methods. This OTP-cellulose pulp was subjected to a further purification process by bleaching, thus bringing the cellulose content up to 86.1%wt. This highly purified cellulose was hydrolysed with sulfuric acid to obtain CNCs with an average length of 267 nm and a degradation temperature of 300 °C. The CNCs obtained were used in different percentages (1, 3, and 5%wt.) as reinforcement in the manufacture of PLA-based composites. The effect of incorporating CNC into PLA matrix on the mechanical, water absorption, thermal, structural, and morphological properties was studied. Maximum tensile stress and Young's modulus improved by 87 and 58%, respectively, by incorporating 3 and 5%wt. CNC. Charpy impact strength increased by 21% with 3%wt. These results were attributed to the good dispersion of CNCs in the matrix, which was corroborated by SEM images. Crystallinity index, glass transition, and melting temperatures were maintained.

A hybrid microcrystalline cellulose/metal-organic framework for dispersive solid phase microextraction of selected pharmaceuticals: A proof-of-concept

Solid phase microextraction (SPME) is considered simple, ecofriendly, sustainable, cost-effective and timesaving sample preparation mode in comparison with other sample preparation procedures. The researchers always try to develop new sorbents with higher surface area in comparison with other conventional sorbents aiming to enhance the extraction efficiency. In this work for the first time, a comparative study was performed between Ca-BTC MOF (1,3,5-benzenetricarboxylic acid, BTC; metal-organic framework, MOF) and a hybrid Ca-BTC-MCC MOF (microcrystalline cellulose, MCC) by using as model compounds seven drugs with different physicochemical properties. The evaluation of the extraction efficiency of both sorbents were obtained by means of an HPLC/DAD instrument configuration in reversed phase mode under isocratic elution mode. The results indicate that Ca-BTC MOF showed superior extraction efficiency than Ca-BTC-MCC MOF in the case of all analytes except nirmatrelvir and ritonavir. The results highlight that not only the surface area of adsorbents controlled the adsorption capacity, but also other factors have a role in extraction efficiency including morphology of adsorbent and physico-chemical properties of the analytes. It is worth mentioning that this is the first time that a comparative study was performed between Ca-BTC MOF and Ca-BTC-MCC MOF hybrid material.

Microcrystalline Cellulose Isolation and Impregnation with Sappan Wood Extracts as Antioxidant Dietary Fiber for Bread Preparation

Microcrystalline cellulose (MCC) has gained considerable attention as a functional ingredient in bread making. This work demonstrates the isolation of MCC from sugar cane bagasse (SCB) for preparing bread. The effect of MCC on bread attributes and antioxidant activity by impregnation with sappan wood extract (SAP) was evaluated. The highest crystallinity index and suitable size of MCC were achieved at 85 °C under 90 min hydrolysis condition. Increasing MCC/SAP levels in bread showed a significant increase in bread color with decreases in the specific volume and baking loss. There was a positive correlation between bread texture and the MCC/SAP level. The addition of MCC/SAP interfered with the bread hardness. Low MCC/SAP levels have no effect on springiness and cohesiveness; however, 4% MCC/SAP has significantly decreased these attributes, with the highest antioxidant activity and phenolic content. Therefore, MCC can be functionalized with SAP as an antioxidant fiber additive for health benefits in bakery products.

Synthesis of cellulosic and nano-cellulosic aerogel from lignocellulosic materials for diverse sustainable applications: a review

Cellulosic aerogels are sustainable, biodegradable, and ultra-light porous materials with three-dimensional networks having high specific surface area. Depending on the source of precursor materials, they are categorized into plant-based aerogel, bacterial cellulosic aerogel. Different types of aerogels are also produced from microcrystalline cellulose (MCC), nanocrystalline cellulose (NCC), cellulose microfibril (CMF) and cellulose nanofibril (CNF). Furthermore, inorganic and organic substances are embedded to produce hybrid aerogel or composite aerogel for the enhancement of its performance in various fields. Mixing, gelation, solvent exchange, and drying (e.g., super critical carbon dioxide or freeze drying) are the basic steps involved in cellulosic aerogel synthesis. Based on the composition of precursors during aerogel synthesis, cellulosic aerogels have broad applications in various fields such as adsorbents, electrodes, sensors, captive deionization materials, catalysts, drug delivery, thermal and sound insulating materials. This review provided consolidated information on: (i) classification of cellulosic aerogels based on the sources of raw materials, (ii) processes involved to produce the cellulosic aerogel, (iii) cellulosic aerogel synthesized from MCC, NCC, CMF and CNF, (iv) nano particle doped cellulosic aerogel, and (v) its application in various field with future perspectives.

Microwave-assisted quick synthesis of microcrystalline cellulose from black tea waste (Camellia sinensis) and characterization

Tea wastes generated in the industries during tea production processes show excellent potential to be used as a renewable, abundant, and cheap source for the extraction of microcrystalline cellulose. In the current work, MCC was isolated from black tea waste through microwave heating instead of using conventional heating and avoiding the traditional acid hydrolysis method. Microwave increased the reaction speed significantly and resulted in very quick delignification and bleaching of black tea waste to isolate MCC in white powdered form. FTIR, XRD, FESEM, and TGA analysis were then carried out to investigate the chemical functionality, crystallinity, morphology, and thermal properties, respectively, of the synthesized tea waste MCC. The characterization results demonstrated that cellulose with a short rough fibrous structure having an average particle size of around 23 μm was extracted. The results of FTIR and XRD demonstrated unequivocally that all amorphous non-cellulosic compounds had been eliminated. The microwave-extracted black tea waste MCC showed 89.77 % crystallinity and good thermal properties, indicating that it could be a promising filler material for preparing polymer composites. Therefore, microwave-assisted delignification and bleaching can be used as a suitable, energy-efficient, time-saving and low-cost method for extracting MCC from the black tea waste produced in tea factories.

Optimization of microfibrillated cellulose isolation from cocoa pod husk via mild oxalic acid hydrolysis: A response surface methodology approach

Theobroma cacao L. species, cultivated worldwide for its valuable beans, generates up to 72% weight of the fruit as waste. The lack of reutilization technologies in the cocoa agroindustry has hindered the exploitation of valuable bio-components applicable to the generation of high value added bioproducts. One such bioproduct is microfibrillated cellulose (MFC), a biopolymer that stands out for its desirable mechanical properties and biocompatibility in biomedical, packing, 3D printing, and construction applications. In this study, we isolated microfibrillated cellulose (MFC) from cocoa pod husk (CPH) via oxalic acid hydrolysis combined with a steam explosion. MFC isolation started with the Solid/Liquid extraction via Soxhlet, followed by mild citric acid hydrolysis, diluted alkaline hydrolysis, and bleaching pre-treatments. A Response Surface Methodology (RSM) was used to optimize the hydrolysis reaction at levels between 110 and 125 °C, 30-90 min at 5-10% (w/v) oxalic acid concentration. The cellulose-rich fraction was characterized by Fourier-Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) analyses. Characterization analyses revealed a cellulose-rich polymer with fibers ranging from 6 to 10 μm, a maximum thermal degradation temperature of 350 °C, and a crystallinity index of 63.4% (peak height method) and 29.0% (amorphous subtraction method). The optimized hydrolysis conditions were 125 °C, 30 min, at 5% w/v oxalic acid: with a 75.7% yield. These results compare with MFC obtained through highly concentrated inorganic acid hydrolysis from different biomass sources. Thus, we show a reliable and greener alternative chemical treatment for the obtention of MFC.

Study of Unsaturated Polyester Primer Reinforced by Microcrystalline Cellulose on Mechanical, Adhesion and Corrosion Properties

Addition of Microcrystalline Cellulose (MCC) as filler in to Unsaturated Polyester (UPR) polymer can enhanced the properties of the composite. UPR and MCC was prepared using sonication mixing technique at various loading of (2, 4, 6, 8, and 10 wt %) of MCC at a constant of 60 minutes of sonication. UPR and MCC was mixed in a vial bottle and then immersed in sonication bath for the sonication process. Once the sonication completed, the mixture was added with Methyl Ethylene Ketone Peroxide (MEKP) as curing agent, coated on steel plate and was left for curing process of 7 days. The coating was studied for adhesion, mechanical and corrosive properties using pencil hardness, adhesion tape and immersion tests. 4 wt% of loading showed improvement in mechanical properties where form H grade to 4H grade. It is also recorded there are improvement of adhesion test from 1B grade 35-65% pulled out to 4B grade which is less than 5 % pulled. From the immersion test, it shown that 4 wt % of loading has a good corrosion resistant as compared to the control sample. Thus, it was concluded that 4 wt % of loading filler is suitable to be used because it promotes a better mechanical and adhesion properties and also good corrosion resistant compared to other loading percentage.

Development of polylactic acid based antimicrobial food packaging films with N-halamine modified microcrystalline cellulose

Bio-based "green" films with superior antimicrobial activity were developed from polylactic acid (PLA) and cyclic N-halamine 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone (MC) grafted microcrystalline cellulose (MCC) fibers (herein referred to as g-MCC). The structure of g-MCC was characterized by Fourier Transform Infrared (FT-IR) and Nuclear Magnetic Resonance (NMR) spectroscopy. Results indicated N-halamine MC was successfully grafted onto MCC fibers, with a grafting percentage of 10.24 %. The grafting improved compatibility between g-MCC and PLA, leading to an excellent dispersion of g-MCC in the film matrix, and a superior transparency of the g-MCC/PLA compared to that of the MCC/PLA films. Additionally, the enhanced compatibility the g-MCC/PLA films produced better mechanical properties including mechanical strength, elongation at break and initial modulus than those of both MCC/PLA and MC/PLA composites. With N-halamine, g-MCC/PLA completely inactivated all the inoculated Escherichia coli and Staphylococcus aureus within 5 and 30 min of contact, respectively. More importantly, the migration test showed that the oxidative chlorine of g-MCC/PLA was highly stable than that of MC/PLA films, providing a long-term antimicrobial activity. Finally, preservation test conducted on fresh bread slices further demonstrated its promising applications in the food industry.

Valorization of cocoa, tea and coffee processing by-products-wastes

The growing threat of food insecurity together with some challenges in demography, health, malnutrition, and income instability around the globe has led researchers to take sustainable solutions to ensure secure production and distribution of food. The last decades have been remarkable in the agri-food supply chain for many food industries. However, vast quantities of food by-products and wastes are generated each year. These products are generally disposed in the environment, which could have remarkable adverse effects on the environment and biodiversity. However, they contain significant quantities of bioactive, nutritional, antioxidative, and aroma compounds. Their sustainable use could meet the increased demand for value-added pharmaceutical, nutraceutical, and food products. The amount of agri-food wastes and their disposal in the environment are predicted to double in the next decade. The valorization of these by-products could effectively contribute to the manufacture of cheaper functional food ingredients and supplements while improving regional economy and food security and mitigating environmental pollution. The main aim of this chapter is to present an understanding of the valorization of the wastes and by-products from cacao, coffee and tea processing with a focus on their bioactive, nutritional, and antioxidant capacity.

Study on the Preparation and Properties of Jute Microcrystalline Cellulose Membrane

The preparation and performance control of the cellulose membrane are one of the hot topics in the environmentally friendly separation membrane field. In this study, microcrystalline cellulose (MCC) was prepared by microwave-assisted acidic hydrolysis of cellulose obtained from jute, followed by the use of a mixture of N-methylmorpholine-N-oxide and water as a solvent to obtain the homogeneous casting liquid, which was scraped and subsequently immersed in the coagulation bath to form a smooth and dense cellulose membrane. During membrane formation, the crystal structure of MCC changed from type I to type II, but the chemical structure remained unchanged. The mechanical strength and separation performance of the membrane were related to the content of MCC in the casting liquid. When the content of MCC was about 7%, the tensile strength of the membrane reached a maximum value of 13.49 MPa, and the corresponding elongation at break was 68.12%. The water flux (J) and rejection rate (R) for the bovine serum albumin were 19.51 L/(m²·h) and 95.37%, respectively, under an optimized pressure of 0.2 MPa. In addition, the coagulation bath had a significant effect on the membrane separation performance, and J and R were positively and negatively correlated with the polarity of the coagulation bath. Among them, it was note-worthy that J and R of membrane formed in ethanol were 33.95 L/(m²·h) and 91.43%, separately. Compared with water as a coagulation bath, J was increased by 74% at the situation and R was roughly equivalent, showing better separation performance. More importantly, the relationship between the structure and separation performances has also been studied preliminarily. This work provides certain guidance for the preparation of high-performance MCC membranes.

Preparation of microcrystalline cellulose from agricultural residues and their application as polylactic acid/microcrystalline cellulose composite films for the preservation of Lanzhou lily

Microcrystalline celluloses were isolated from four agricultural residues, including sweet sorghum stalk, Jerusalem artichoke stalk, grains stillage, and Chinese herb residue, and characterized in terms of physicochemical and structural properties. The obtained microcrystalline celluloses were composited with polylactic acid as a packing film for the preservation of Lanzhou lily. All the agricultural residues-derived microcrystalline celluloses were in cellulose I_β structure with high purity and good thermal stability. Microcrystalline celluloses from sweet sorghum stalk had a higher degree of polymerization (327) and crystallinity (70.52 %) than others. The preservation effect of lily bulbs packaged by films were significantly improved indicated by the lessened weight loss rate and the meliorative hardness and whiteness, which ascribe to the repressed oxidation reactions. Polylactic acid/microcrystalline cellulose composite films prepared from sweet sorghum straw have been proved the most effective. This work could offer a value-added outlet for agricultural residues to produce microcrystalline celluloses-based biocompatible films for preservation of Lanzhou lily.

Polysaccharides Obtained from Vegetables: an effective source of alternative excipient

Polymers are the major constructive material of pharmaceutical formulations that play a prime role in designing effective drug-delivery systems and releasing drugs at their sites of application. Polymers are composed of multiple repeating units of high molecular mass components with attendant properties. Most synthetic polymers are non-biocompatible, expensive, and extremely inclined to deliver adverse impacts. Meanwhile, edible polymers obtained from natural sources have gained remarkable recognition for their promising use in modern medicine. Moreover, polymers derived from natural sources are generally preferred due to certain of their unique features such as abundant availability, biocompatibility, nontoxicity, economical, safe, and effective functions that fit the purpose. Polysaccharides including starch, cellulose, hemicellulose, pectin, and mucilage are identified as a major class of naturally obtained molecules that have a substantial role as functional polymers. This review summarizes the potential role of polysaccharides derived from vegetable sources such as adhesives, anticaking agents, binders, disintegrants, emulsifiers, film-framing agents, and thickeners. This is simply an opportunity to abandon synthetic excipients that hurt our bodies and think back to nature from where we originate.

Physical and Spectroscopic Characterization of the Microcrystalline Cellulose Derivatives from Corn Cob and Daniella Oliveri Wastes

Cellulose was extracted from wood dust waste samples of Daniella oliveri and corn cobs by acetic acid and alkaline pretreatment methods, while microcrystalline cellulose (MCC) derivative was produced by acid hydrolysis in 2 M HCl. The samples were tested for pH, moisture content, swelling capacities and ash contents. The data obtained were compared with those of commercial MCCs found in the literature. The functional groups in the microcrystalline cellulose derivatives was confirmed by the Fourier transform infrared (FTIR) spectroscopic method with characteristic absorption bands of;–OH stretching at 3416 cm-1; C-H stretching at 2918 cm-1; -OH bending at 1377 cm-1; 1159 cm-1; and C-O-C pyranose ring skeletal vibrations at 1026-1033 cm-1. The crystallinity absorption bands appeared at 1436 and 850 cm-1. The characteristic morphological features were established by scanning electron microscopy (SEM). Furthermore, the crystallinity of the microcrystalline cellulose was further confirmed using the X-ray powder diffraction (X-RD) technique, which showed three main reflections at 2θ=14.70°, 22.09°, and 34.24°.These results supported that microcrystalline cellulose derivative as cellulose I type and the acid pretreatment did not affect the structure of the MCC. The crystallinity indices were 69.3 and 73.2%, respectively. Daniella Oliveri and corn cob microcrystalline cellulose are, therefore, potential materials for further processing.

Effect of Microcrystalline Cellulose on the Properties of PBAT/Thermoplastic Starch Biodegradable Film with Chain Extender

Poly (butylene adipate-co-terephthalate) (PBAT) is a fully biodegradable polymer with toughness and ductility. It is usually compounded with thermoplastic starch (TPS) to balance the cost for manufacturing biodegradable films such as disposable plastic bags. However, blending with TPS reduces valuable tensile strength, which limits the bearing capacity of PBAT film. In this study, microcrystalline cellulose (MCC) was employed as a reinforcement to strengthen the PBAT/TPS biodegradable film. The effect of MCC content on the mechanical, thermal, and morphological properties of the composite film were investigated. The optimal tensile strength and elongation at break reached 5.08 MPa and 230% when 4% MCC was added. The thermal stability and thermal resistance were improved with the addition of MCC; for example, Tmax increased by 1 °C and Tonset increased by 2-8 °C. Moreover, good compatibility among PBAT, TPS, and MCC can be achieved when the MCC content was below 6%. Consequently, the optimal MCC content was found to be 4%. These results could provide experimental data and method support for preparing high-performance PBAT hybrid films.

Survivability of probiotics encapsulated in kelp nanocellulose/alginate microcapsules on microfluidic device

Probiotics are living microorganisms that can produce health benefits to the host only when they are ingested in sufficient quantities and reach the intestines active state. However, the external environment that probiotics face for a long time before administration and the low pH environment in the stomach after administration can greatly reduce their activity. In this work, we proposed a simple microfluidic encapsulation strategy to efficiently prepare the probiotics-loaded nanocellulose/alginate delivery system, which can improve the storage stability and gastrointestinal survival rate of probiotics. The microcapsules were found to be monodisperse, and the average particle size was<500 μm by observing the microstructure and macroscopic morphology. The kelp nanocellulose was cross-linked in the microcapsule and formed a dense surface with alginate. Through the simulated gastrointestinal digestion experiment, it was found that the survival of probiotics in microcapsules containing 0.5 % and 1.5 % kelp nanocellulose decreased by 1.77 log CFU/g and 1.65 log CFU/g respectively, which was significantly lower than that of nanocellulose-free microcapsules (3.70 log CFU/g). And all the treated groups could release probiotics above 7 log CFU/g after digesting intestinal juice for 6 h. Furthermore, through the storage experiment, it was found that the microcapsules with 1.5 % kelp nanocellulose could still release 8.07 log CFU/g probiotics after four weeks. The results provide a new strategy for probiotics processing and extensive high-value utilization of marine natural products.

Characterizations of Alpha-Cellulose and Microcrystalline Cellulose Isolated from Cocoa Pod Husk as a Potential Pharmaceutical Excipient

Cellulose is a non-toxic, bio-degradable, and renewable biopolymer which is abundantly available in nature. The most common source of commercial microcrystalline cellulose is fibrous wood pulp. Cellulose and its derivatives have found wide commercial applications in the pharmaceutical, cosmetic, food, paper, textile, and engineering industries. This study aims to isolate and characterize cellulose forms from cocoa pod husk (CPH) and to assess its mechanical and disintegration properties as a direct compression excipient in metronidazole tablets. Two isolated cellulose types (i.e., cocoa alpha-cellulose (CAC) and cocoa microcrystalline cellulose (C-MCC)) were compared with avicel (AV). CAC and C-MCC were characterized for their physicochemical properties using Scanning Electron Microscopy (SEM), FTIR spectroscopy, Differential Scanning Calorimetry (DSC), and X-Ray Powder Diffraction (XRD). Metronidazole tablets were produced by direct compression with cellulose. The mechanical and disintegration properties of the tablets were evaluated. CAC and C-MCC yield was 42.3% w/w and 38.25% w/w, respectively. Particle diameters were significantly different with CAC (282.22 μm) > C-MCC (161.32 μm) > AV (72.51 μm). CAC and C-MCC had a better flow than AV. SEM revealed the fibrous nature of the cellulose. FTIR and XRD analysis confirmed the presence of cellulose with crystallinity index of 69.26%, 43.83%, and 26.32% for AV, C-MCC, and CAC, respectively. C-MCC and AV are more crystalline and thermally stable at high temperatures compared to CAC. The mechanical and disintegration properties of C-MCC and AV tablets complied with pharmacopeia specifications. Taken together, C-MCC isolated from CPH displayed some fundamental characteristics suitable for use as a pharmaceutical excipient and displayed better properties compared to that of AV.

Preparation of Cellulose Nanocrystals from Jujube Cores by Fractional Purification

Jujube cores are fiber-rich industrial waste. Dewaxing, alkali treatment, bleaching, and sulfuric acid hydrolysis were used to generate cellulose nanocrystals (CNCs) from the jujube cores in this study. The morphological, structural, crystallinity, and thermal properties of the fibers were investigated using FE-SEM, TEM, AFM, FT-IR, XRD, and TGA under various processes. CNCs’ zeta (ζ) potential and water contact angle (WAC) were also investigated. The findings demonstrate that non-fibrous components were effectively removed, and the fiber particles shrunk over time because of many activities. CNCs had a rod-like shape, with a length of 205.7 ± 52.4 nm and a 20.5 aspect ratio. The crystal structure of cellulose Iβ was preserved by the CNCs, and the crystallinity was 72.36%. The temperature of the fibers’ thermal degradation lowered during the operations, although CNCs still had outstanding thermal stability (>200 °C). Aside from the CNCs, the aqueous suspension of CNCs was slightly agglomerated; thus, the zeta (ζ) potential of the CNCs’ suspension was −23.72 ± 1.7 mV, and the powder had high hydrophilicity. This research will be valuable to individuals who want to explore the possibility for CNCs made of jujube cores.

Extraction and Characterization of Microcrystalline Cellulose from Lagenaria siceraria Fruit Pedicles

Microcrystalline cellulose (MCC) is a versatile polymer commonly employed in food, chemical, and biomedical formulations. Lagenaria siceraria (bottle gourd) fruit is consumed in many parts of the world, and its pedicle is discarded as waste. In the quest for a novel renewable source of the MCC, the present study investigates the extraction and characterization of MCC from the pedicle of Lagenaria siceraria fruits. The MCC was extracted by sequentially treating pedicles with water, alkali, bleaching (sodium chlorite), and dilute sulfuric acid (acid hydrolysis). The removal of associated impurities from pedicle fibers was confirmed by Fourier transform infrared analyses. The extracted MCC exhibited a characteristic crystalline structure of cellulose in X-ray diffraction with a 64.53% crystallinity index. The scanning electron microscopy (SEM) showed the variation in the morphology of the fibers and the formation of MCC of approximately 100 µm. The thermogravimetric analysis (TGA) indicated higher thermal stability of MCC. MCC production from biowaste (pedicle) holds potential for application as an emulsifier, stabilizer, and thickener in the chemical, pharmaceutical, and food industries.

Characteristics of Pickering emulsions stabilized by tea water-insoluble protein nanoparticles at different pH values

This study aimed to explore the characteristics of Pickering emulsions stabilized by tea water-insoluble protein nanoparticles (TWIPNs) at different pH values. The characteristics of TWIPNs at different pH values were analysed first. The average hydrodynamic diameter of TWIPNs in the suspension was smaller than 400 nm at pH 7-11. TWIPNs at pH 3 could not be used to stabilize Pickering emulsions. The flocculation index (FI) of fresh TWIPN-stabilized Pickering emulsions (TWIPNPEs) at pH 5 was higher than those of TWIPNPEs at pH 7-11 (FI < 5%), indicating that bridging flocculation led to the aggregation of small emulsion droplets. The zeta potential of TWIPNPEs at pH 7-11 did not change after 7 d. In addition, the TWIPNPEs showed gel-like properties under neutral and alkaline conditions. These results will be helpful for broadening the application of TWIPNPEs at different pH values.

A critical review on the techniques used for the synthesis and applications of crystalline cellulose derived from agricultural wastes and forest residues

In order to meet the growing energy crisis of the 21st century, the utilization of bio-based materials has become a field of high research endeavour. In view of that, the present review paper is focused on different techniques that are frequently explored for the synthesis of value-added crystalline derivatives of cellulose like MCC and NCC from agricultural wastes and forest residues. Moreover, a comparative analysis between thermochemical and biochemical methods is carried out for such valorization of biomass considering the mechanism involved with various reactions. Further, a critical analysis is performed on various individual techniques specifically used for the applications of MCC and NCC in different fields including environmental, polymer industry, pharmaceutical and other emerging sectors. This article will assist the readers not only to explore new biomass sources but also provides an in-depth insight on various green and cost-effective methods for sustainable production of crystalline cellulose.

Synthesis and Physicochemical Properties of Poly(vinyl) Alcohol Nanocomposites Reinforced with Nanocrystalline Cellulose from Tea (Camellia sinensis) Waste

The purpose of this study was to utilize cellulose from tea waste as nanocrystalline cellulose (NCC), which is used as a filler in poly(vinyl) alcohol (PVA) nanocomposites. To obtain the NCC, a chemical process was conducted in the form of alkali treatment, followed by bleaching and hydrolysis. Nanocomposites were formed by mixing PVA with various NCC suspensions. With chemical treatment, lignin and hemicellulose can be removed from the tea waste to obtain NCC. This can be seen in the functional groups of cellulose and the increase in crystallinity. The NCC had a mean diameter of 6.99 ± 0.50 nm. Furthermore, the addition of NCC to the PVA nanocomposite influenced the properties of the nanocomposites. This can be seen in the general increase in opacity value, thermal and mechanical properties, and crystallinity, as well as the decrease in the value of the swelling ratio after adding NCC. This study has revealed that NCC from tea waste can be used to improve the physicochemical properties of PVA film.

Preparation of microcrystalline cellulose from Rabdosia rubescens residue and study on its membrane properties

Microcrystalline cellulose (MCC) was prepared easily from Rabdosia rubescens residue to realize the efficient utilization of waste resources. The yield was about 95.03% under the optimal conditions. Then, MCC membrane was prepared by phase transformation method and its structure and mechanical properties were studied systemically. The results showed the cellulose crystal structure changed from type I to type II in the process of forming membrane, and the thermal stability decreased simultaneously. The content of MCC in casting solution has great influence on the mechanical properties of membranes. The higher the content of MCC, the better the comprehensive mechanical properties of the membranes is. When MCC content is 9%, the tensile strength and elongation at break can reach 8.38 MPa and 26.72%, which is better than traditional cellulose membranes. Finally, the separation properties were studied by separation BSA from water. The results showed that the rejection rate and water flux changed positively and negatively with the change of MCC content. When the content was 5%, the membrane demonstrated the best comprehensive performance, its rejection for BSA was 37.23 g/(m² h), the corresponding rejection rate and water flux were 88.87% and 41.89 L/(m² h) respectively.