High-pressure Homogenization Research Articles

Tailoring pea proteins gelling properties by high-pressure homogenization for the formulation of a model spreadable plant-based product

This study investigated the impact of high-pressure homogenization (HPH) at varying intensities on the gelling properties of a commercial pea protein concentrate for the formulation of emulsion-filled gels as a model spreadable plant-based product. As a preliminary characterization, pea protein dispersions (10%-15%–20% w/w) underwent HPH treatments, 60 and 150 MPa for 5 cycles. Mechanical characteristics of heat-set gels were evaluated through rheological measurements. Emulsion-filled gels were then produced, starting from a common primary emulsion, incorporating either native or treated pea protein suspensions, and characterized with frequency and amplitude sweep tests, back extrusion, texture profile analysis (TPA) and confocal laser scanning microscopy (CLSM). Results revealed that HPH treatments had a significant influence on the aggregation state of protein suspensions reducing residue size, but inducing the formation of new, albeit smaller, agglomerates, with a direct impact on gel network formation. Treatment at 150 MPa consistently produced a stiffer, compact, and elastic gel structure, as confirmed by frequency sweep, back extrusion and TPA tests. Additionally, when this structure was disrupted, it exhibited creamy-viscous characteristics, as verified by amplitude sweep analyses. CLSM micrographs showed the formation of a more structured and compact gel matrix with the increase of the pressure applied.

Stability of oil-in-water emulsion and immunomodulating activity in S180 tumor-bearing mice.

The stability and nutritional integrity of emulsions are susceptible to various factors including thermal treatment, solid-liquid ratio, and sterilization. In this study, the physicochemical stability and immunomodulatory activities of an oil-in-water emulsion containing immune peptides (TUFSE) were assessed through particle size, zeta potential, related cytokines, and so on. When the temperature was 70°C and a solid-liquid ratio of 1:4, the emulsion revealed stability at high-pressure homogenization, with the small particle size. The loss rates of vitamins were 8.57%-62.26% in 6 months at 25°C. After treatment with cyclophosphamide (CTX), lymphocyte proliferation activity in TUFSE-H group increased (p<0.05), and immune globulin levels were notably elevated (p<0.05) in TUFSE groups compared to model group. It confirms the parameters of the emulsion, suggesting its ability to be prepared with minimal vitamin loss while simultaneously improving the disease status in CTX-treated tumor-bearing mice. It shows potential as an immune-enhancing supplement with significant potential value. PRACTICAL APPLICATION: This study validated the parameters of the oil-in-water emulsion and showed that it can be stably prepared with minor vitamin loss while simultaneously improving the disease status in CTX-treated tumor-bearing mice. TUFSE-H group exhibited a notable increase in lymphocytes proliferation activity, whereas serum cytokines and immune globulin levels were elevated compared to MC group, indicating its potential as an immune-enhancing supplement with substantial value.

Quality by design driven development of lipid nanoparticles for cutaneous targeting: a preliminary approach.

Fungal infections are the fourth common cause of infection affecting around 50 million populations across the globe. Dermatophytes contribute to the majority of superficial fungal infections. Clotrimazole (CTZ), an imidazole derivative is widely preferred for the treatment of topical fungal infections. Conventional topical formulations enable effective penetration of CTZ into the stratum corneum, however, its low solubility results in poor dermal bioavailability, and variable drug levels limit the efficacy. The aim was to increase dermal bioavailability and sustain drug release, thereby potentially enhancing drug retention and reducing its side effects. This work evaluated the CTZ loaded solid lipid nanoparticles (SLN) consisting of precirol and polysorbate-80 developed using high pressure homogenization and optimized with QbD approach. Prior to release studies, CTZ-SLNs were characterized by different analytical techniques. The laser diffractometry and field emission scanning electron microscopy indicated that SLNs were spherical in shape with mean diameter of 450 ± 3.45nm. DSC and XRD results revealed that the drug remained molecularly dispersed in the lipid matrix. The CTZ-SLNs showed no physicochemical instability during 6months of storage at different temperatures. Further, the Carbopol with its pseudoplastic behavior showed a crucial role in forming homogenous and stable network for imbibing the CTZ-SLN dispersion for effective retention in skin. As examined, in-vitro drug release was sustained up to 24h while ex-vivo skin retention and drug permeation studies showed the highest accumulation and lowest permeation with nanogel in comparison to pure drug and Candid® cream. Further, the in-vivo antifungal efficacy of nanogel suggested once-a-day application for 10days, supported by histopathological analysis for complete eradication infection. In summary, the findings suggest, that nanogel-loaded with CTZ-SLNs has great potential for the management of fungal infections caused by Candida albicans.

A natural protein-lipid co-assembly as efficient Pickering emulsifier from egg yolk sphere microgel prepared via high-pressure homogenization

Egg yolk sphere is a kind of natural colloidal histological structure formed by the co-assembly of a large number of proteins and lipids, which has the dual functions of hydrophilic and lipophilic for application in emulsion. In this study, egg yolk sphere microgels (EYSMs) were prepared by high pressure homogenization (HPH) technique at various pressures (0–90 MPa) and used as Pickering emulsifiers for emulsification to obtain oil-in-water emulsions with an oil-water ratio of 11:9. The microscopic morphology, structure, and physicochemical properties of EYSMs were analyzed. The results showed that EYSMs obtained at 60 MPa (60-EYSMs) exhibited superior emulsifying properties with an emulsifying activity index (EAI) of 2.8 m2/g and an emulsifying stability index (ESI) of 356.6 min, resulting in enhanced storage stability of the emulsion for 30 d. The HPH treatment decreased the lipid content in EYSMs while creating a more homogeneous protein-lipid arrangement, which provided EYSMs with balanced hydrophilic and hydrophobic sites to improve emulsifying properties. Furthermore, the free sulfhydryl groups and hydrophobic moieties exposed by HPH promoted -S-S- formation on the EYSMs surface, promoting the increase in surface hydrophobicity and emulsifying ability. The confocal laser scanning microscopy (CLSM) and cryogenic scanning electron microscopy (cryo-SEM) revealed that the EYSMs adsorbed at oil-water interface and formed an intercross-linked spatial three-dimensional network structure, which worked as a physical barrier to the stable emulsion formation. This study introduces a novel research concept and delves into the emulsification mechanism of protein-lipid composite particles, offering a fresh insight for the development and utilization of emulsifiers.

Effects of soybean-oil and emulsifiers mixture on rheological properties of oil-in-water emulsions

The effects of soybean-oil and emulsifiers mixture on rheological properties of oil-in-water emulsions were investigated. Polysorbate-80 and sorbitan-monooleate in the ratio 1:3 were added to stabilize a soybean-oil emulsion by high-pressure homogenization at 50 and 100 MPa. Particle size and rheological properties were measured. The z-average size value showed all the droplets ranging from 295.5 to 302.3 nm. The emulsions were Newtonian and non-Newtonian pseudoplastic at 50 MPa, although at 100 MPa exhibited a Newtonian behavior, preferably. The highest concentrations of soybean-oil and emulsifiers mixture showed semi-solid emulsions (at 50 MPa), and the lower concentrations of soybean-oil and emulsifiers mixture, showed semi-solid emulsions (at 100 MPa), however, elastic character predominated over viscous character (G’&gt;G’’), for both pressures. In conclusion, the emulsion systems were nanoemulsions and their droplet size distribution was bimodal. The nanoemulsions had a non-Newtonian behavior for both pressures, although at 100 MPa the emulsions were Newtonian.

Continuous flow high-pressure homogenization for preserving the nutritional quality and stability of watermelon juice under simulated market storage conditions

This study examined the efficacy of continuous flow high-pressure homogenization (CFHPH) under varying pressures, inlet temperatures, and flow rates, in preserving the nutritional quality and stability of watermelon juice during simulated market conditions and compared it with traditional high-temperature short-time (HTST) processing. The retention of ascorbic acid, carotenoids, and amino acids was analyzed using liquid chromatography, while PPO (polyphenol oxidase) and POD (peroxidase) enzyme activity was assessed using a UV–vis spectrophotometer.We observed a significant decrease (p ≤ 0.05) in ascorbic acid levels after 15 days of storage. For carotenoids, the impact was influenced by the interaction of pressure, flow rate, and inlet temperature within CFHPH, with no clear trend emerging regarding their preservation over 45 days of storage at 4 °C. However, overall retention of carotenoids surpassed that of HTST samples. Both methods enhanced free amino acid contents significantly and decreased PPO and POD activity, with HTST being slightly more effective. Ornithine and histidine concentrations significantly increased, with up to a fourfold rise in samples treated with 300 MPa pressure and up to a tenfold rise for HTST at 95 °C after 45 days of storage. This study suggests optimizing the CFHPH process to enhance the shelf-life and nutritional value of watermelon juice, offering consumers a healthier and longer-lasting choice. Industrial relevanceOur findings highlight CFHPH's higher retention of bioactive compounds, reduction in degradative enzyme activity, and enhancement of the amino acid profile, making it a compelling choice for the fruit juice processing industry. Despite the energy-intensive nature of CFHPH, its ability to preserve vital bioactive compounds like carotenoids and ascorbic acid addresses the growing consumer demand for nutritious and stable juice options. The benefits of CFHPH in maintaining juice quality and nutritional value may outweigh the associated energy costs, making it a promising technology for fruit juice processing.

The influence mechanism of pH and polyphenol structures on the formation, structure, and digestibility of pea starch-polyphenol complexes via high-pressure homogenization

The formation of starch-polyphenol complexes through high-pressure homogenization (HPH) is a promising method to reduce starch digestibility and control postprandial glycemic responses. This study investigated the combined effect of pH (5, 7, 9) and polyphenol structures (gallic acid, ferulic acid, quercetin, and tannic acid) on the formation, muti-scale structure, physicochemical properties, and digestibility of pea starch (PS)-polyphenol complexes prepared by HPH. Results revealed that reducing pH from 9 to 5 significantly strengthened the non-covalent binding between polyphenols and PS, achieving a maximum complex index of 13.89 %. This led to the formation of complexes with higher crystallinity and denser structures, promoting a robust network post-gelatinization with superior viscoelastic and thermal properties. These complexes showed increased resistance to enzymatic digestion, with the content of resistant starch increasing from 28.66 % to 42.00 %, rapidly digestible starch decreasing from 42.82 % to 21.88 %, and slowly digestible starch reducing from 71.34 % to 58.00 %. Gallic acid formed the strongest hydrogen bonds with PS, especially at pH 5, leading to the highest enzymatic resistance in PS-gallic acid complexes, with the content of resistant starch of 42.00 %, rapidly digestible starch of 23.35 % and slowly digestible starch of 58.00 %, and starch digestion rates at two digestive stages of 1.82 × 10–2 min−1 and 0.34 × 10–2 min−1. These insights advance our understanding of starch-polyphenol interactions and support the development of functional food products to improve metabolic health by mitigating rapid glucose release.

Tailoring the structural and physicochemical properties of rice straw cellulose-based cryogels by cell-mediated polyhydroxyalkanoate deposition

This study presents a novel biotechnological approach for creating water vapor-resistant cryogels with improved integrity. Rice straw cellulose was transformed into nanofibrils through TEMPO-mediated oxidation and high-pressure homogenization. The resulting cryogels remained firm even when immersed in aqueous media, whose pores were used by live cell to deposit polyhydroxyalkanoate (PHA) particles inside them. This novel method allowed the compatibilization of PHA within the cellulosic fibers. As a consequence, the water sorption capacity was decreased by up to 6 times having just 4 % of PHA compared to untreated cryogels, preserving the cryogel density and elasticity. Additionally, this technique can be adapted to various bacterial strains and PHA types, allowing for further optimization. It was demonstrated that the amount and type of PHA (medium chain length and small chain length-PHA) used affects the properties for the cryogels, especially the water vapor sorption behavior and the compressive strength. Compared to traditional coating methods, this cell-mediated approach not only allows to distribute PHA on the surface of the cryogel, but also ensures polymer penetration throughout the cryogel due to bacterial self-movement. This study opens doors for creating cryogels with tunable water vapor sorption and other additional functionalities through the use of specialized PHA variants.

In vitro and in vivo evaluation of the layer-by-layer vancomycin with poly(ε-caprolactone) nanosphere-coated Schanz pins for prolonged release

In this research, the effect of layer-by-layer (spray and dip) coating followed by annealing of vancomycin (VCM) and poly(ε-caprolactone) nanospheres (PCLnp) on Schanz pins for prolonged antibacterial activity was investigated. Nanospheres were prepared using the high-pressure homogenizer method and characterized by both functional groups and particle size. The in vitro release profile revealed that after 28 days, the cumulative release of VCM from the VCM-PCLnp coated pins was 753.68 ± 0.19 μg. The coated pins released VCM at a concentration greater than the minimum inhibitory concentration (MIC) and sustained this release for 28 days. Irritation, hemolysis, sensitization, and cytotoxicity assays confirmed that VCM-PCLnp coated pins were highly biocompatible. Additionally, antibacterial assays against methicillin-resistant Staphylococcus aureus (MRSA) revealed prolonged antibacterial resistance. Specifically, the assays demonstrated effective inhibition of Staphylococcus aureus (S. aureus), including the methicillin-resistant strain. This approach involves coating the implants with antibiotics and polymeric nanospheres using a layer-by-layer (dip and spray) method to prolong their antibacterial activity. The results of this study show great promise for successfully treating implant-associated infections. Consequently, we recommend this method for coating other medical devices.

Soluble hemp protein-xylose conjugates fabricated by high-pressure homogenization and pH-shifting treatments.

The process of Maillard conjugation occurs with plant proteins and sugars and can be influenced by several factors, such as processing time, pH, and shear force. By utilizing cavitation processes such as high-pressure homogenization (HPH) and pH-shifting, it is possible to regulate the degree of grafting, functional characteristics, and structural changes in the formation of conjugates. The present study aimed to improve the hemp protein concentrate (HPC) through two different conjugation techniques: HPH and pH-shifting-assisted processes. The best conjugation conditions for the conventional method were identified as a 1:2 HPC to xylose ratio, a pH of 10, and 3 h of treatment at 70 °C. The use of HPH and pH 12-shifting methods resulted in a remarkable 2.5-fold increase in grafting degree, requiring less processing time. Fourier transform infrared spectra confirmed the formation of conjugates. Conjugates produced through HPH with pH 12-shifting (MPHX) transformed into soluble glycoproteins with a particle size of 74 nm. MPHX solubility increased by 5.7-fold than HPC, reaching 85.7%, with a more negatively charged surface at -32.4 mV. Microimages showed cracked and sharp forms for conjugated proteins compared to untreated HPC. Additionally, MPHX conjugates demonstrated superior properties in emulsion stability, foaming capacity, and antioxidant activity compared to HPC and classical conjugates. The use of HPH and pH-shifting-assisted Maillard conjugation was highly effective in enhancing the functional attributes of hemp protein conjugates. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Formulation Optimization and Characterization of Solid Lipid Nanoparticles of Apixaban.

Unpredictable situations such as clotting of blood, deep vein thrombosis, and pulmonary embolism arise in the body, which is the leading cause of mortality. Such conditions generally arise after surgery as well as after treatment with oral anticoagulant agents. Apixaban is a novel oral anticoagulant widely recommended for the prevention and treatment of strokes and blood clots suffering from nonvalvular atrial fibrillation by suppressing factor Xa. Apixaban has a log P of 2.71 with poor solubility and reported maximum bioavailability of approximately 50%. Hence, the current research mainly focused on the improvement of solubility, bioavailability, and therapeutic efficacy of Apixaban via solid lipid nanoparticles (SLN). The SLN was developed using the hot-homogenization method using a high-pressure homogenizer. The drug-lipid compatibility study was assessed by the FTIR, and the thermal analysis was performed using differential scanning calorimetry (DSC). During the scrutiny of lipids, the highest solubility of Apixaban was estimated in the glyceryl monostearate, hence selected for the formulation. Moreover, the colloidal solution was stabilized by the polyethylene glycol 200. The Design of Expert software (Version 13, Stat-Ease) was implemented for the optimization analysis by considering the 3-independent factors and 2-dependent parameters. The Patents on the SLN are Indian 202321053691, U.S. Patent, 10,973,798B2, U.S. Patent, U.S. Patent 2021/0069121A1, U.S. Patent 2022/0151945A1. Box-Behnken design was applied along with ANOVA, which showed a p-value less than 0.05 for the dependent parameters such as particle size and entrapment efficiency (p-value: 0.0476 and 0.0379). The optimized batch F10 showed a particle size of 167.1 nm, -19.5 mV zeta potential, and an entrapment efficiency of 87.32%. The optimized batch F10 was lyophilized and analyzed by Scanning electron microscopy (SEM), which showed a particle size of 130 nm. The solid powder was filled into the capsule for oral delivery. The marked improvement in solubility and bioavailability was achieved with F10- loaded Apixaban via Solid lipid nanoparticles. Moreover, the sustained released profile also minimizes the unseen complications that occur due to the clotting of blood.

Nano-Biochar Prepared from High-Pressure Homogenization Improves Thermal Conductivity of Ethylene Glycol-Based Coolant.

As an environmentally friendly material, biochar is increasingly being utilized in the field of heat transfer and thermal conduction. In this study, nano-biochar was prepared from high-pressure homogenization (HPH) using sesame stalks as the raw material. It was incorporated into ethylene glycol (EG) and its dispersion stability, viscosity, and thermal conductivity were investigated. The nano-biochar was stably dispersed in EG for 28 days. When the concentration of the nano-biochar added to EG was less than 1%, the impact on viscosity was negligible. The addition of 5 wt.% nano-biochar to EG improved the thermal conductivity by 6.72%, which could be attributed to the graphitized structure and Brownian motion of the nano-biochar. Overall, nano-biochar has the potential to be applied in automotive thermal management.

Impact of thermal processing and emulsification methods on spice oleoresin blending: Insights for flavor release and emulsion stability

This study investigated the effect of heat treatments on the pungency and aroma profiles of a spice oleoresin blend, and the emulsion stability with different surfactants, encapsulating agents, and homogenization mechanisms. Total pungency increased with heat until 120 °C and drastically reduced at 150 °C. Thermal processing induced aroma release, and 46 compounds were identified at 90 °C, predominantly comprising sesquiterpenes. Tween 80 dispersed the highest oleoresin mass (6.21 ± 0.31 mg/mL) and reported the maximum emulsion stability index. The oleoresin percentage significantly influenced the emulsion stability, with 1% oleoresin producing the most stable emulsion. High-pressure homogenization applied on gum Arabic resulted in a greater encapsulation efficiency, exceeding 86%, and the lowest creaming index (4.70 ± 0.06%), while Hi-Cap 100 produced the best flow properties. The findings provide insights into incorporating lipophilic spice oleoresin blends in aqueous food systems and understanding the release of flavor compounds during thermal food processing.

Set yogurt incorporated with insoluble dietary fiber maintains non-sedimentation: Combined alkaline hydrogen peroxide modification and high-pressure homogenization process

Insoluble dietary fiber (IDF) settles in set yogurt due to its water insolubility. Making IDF non-settling in set yogurt without thickeners is the current objective. This study attempted to modify IDF with alkaline hydrogen peroxide (AHP) and combine it with a high-pressure homogenization (HPH) process to resolve the settling of IDF in set yogurt. The results showed that AHP-treated IDF (IDF-AHP) altered the structure of IDF, enhanced hydration properties, and had no hydrogen peroxide residue. Set yogurt incorporated with 1, 3, and 5% (w/w) IDF-AHP underwent a HPH process, resulting in non-settling IDF-AHP. The water retention, firmness, and cohesion of yogurt were improved, and the storage modulus (G′) increased during 28-day refrigeration. and the casein gel properties were improved. These results show that combining AHP with HPH treatment prevented the settling of IDF in yogurt and improved its texture. Further studies revealed that AHP and HPH were necessary to prevent IDF from settling in yogurt. This study confirms the applicability of the method and provides new ideas for the commercial production of IDF yogurt.

Modification of soybean lipophilic protein based on pH-shifting and high-pressure homogenization: Focus on structure, physicochemical properties and delivery vehicle

High-pressure homogenization and pH-shifting can be used to modify soybean lipophilic protein (SLP), and to enhance its ability to deliver vitamin B12. The structural changes of SLP were analyzed by multispectral techniques and the results showed that secondary and tertiary structures of SLP were altered by modification. The modification unfolded the SLP structure, released more free hydrogen ions, and increased positive charge density on the protein surface. Also, the solubility of modified SLP increased by maximum of 34.75 %. Furthermore, molecular docking showed that complexes were formed between SLP and vitamin B12 mainly through hydrogen bonding and hydrophobic interactions, and the encapsulation rate of modified SLP was maximally increased by 2.3 %. In vitro digestion showed that modified SLP enhanced stability and bioaccessibility of vitamin B12. This study provides theoretical basis for modification of SLP and effective delivery of bioactive substances.

3D printing of pickering emulsion gels of protein particles prepared by high pressure homogenization and heating

In this study, oil-in-water Pickering emulsion gels stabilized by soybean protein isolate microgel particles were prepared by a combination of high pressure homogenization and heating. These particles swiftly adsorbed onto the oil-water interface stabilizing drops. Cryo-SEM showed the formation of small droplets wrapped in a three-dimensional network structure of protein particles. Heating and increasing the oil content and particle concentration can improve the viscosity, energy storage modulus and gel strength of the system, which is conducive to improving the ability to 3D print these emulsions. The shear-thinning properties allow the system to be extruded smoothly through the nozzle with good printability. When the oil content was 60%, the accuracy and stability of the printed modeling reached 91.8% and 97.2%, respectively. In the future, the excellent properties of Pickering emulsion gel can be further utilized to load active ingredients, optimize and adjust the taste, and prepare food suitable for the elderly and other people with swallowing disorders with the help of 3D printing technology, and achieve the delivery of precise nutrition.

Nano-emulsion based on Santolina chamaecyparissus essential oil potentiates the cytotoxic and apoptotic effects of Doxorubicin: an in vitro study

Aim This study was aimed at investigating the cytotoxic effect of a novel combination of doxorubicin (DOX) and nano-formulation of Santolina chamaecyparissus L. essential oil (SCEO-NANO) on hepatic (HepG2) and colon (HT29) cancer cell lines. Methods A nano-emulsion was prepared by high-pressure homogenisation, then analysed by zetasizer and Fourier transform infrared spectroscopy. HepG2 and HT29 cells were used in in vitro tests for apoptosis detection. Results Formulated droplet size increased in DOX@SCEO-NANO/DOX to 11.54 ± 0.02 with uniform distribution (PDI = 0.13 ± 0.01), when compared with SCEO-NANO (size: 8.91 ± 0.02 nm; PDI = 0.1 ± 0.02). In both cells, DOX@SCEO-NANO/DOX led to a considerable reduction in colony formation. Compared to DOX, apoprotein proteins were overexpressed in HepG2 cells, showing increases of 8.66-fold for caspase-3 and 4.24-fold for the Bax/Bcl-2 ratio. In HT29 cells, ROS-dependent necrosis and apoptosis were seen. Comparing DOX@SCEO-NANO/DOX versus DOX, greater levels of caspase-3 and the Bax/Bcl-2 ratio were observed. Conclusion The DOX@SCEO-NANO/DOX formulation showed potential for targeted eradication of colon adenocarcinoma and hepatocellular carcinoma cells.

Effect of sesame protein isolate modified by high-pressure homogenization, high-intensity ultrasound, and high-pressure processing on the colloidal stability of sesame paste: Determination of physicochemical, rheological, microstructural properties and storage stability

In this study, sesame protein isolate modified with different emerging technologies, including high-pressure homogenization, high-intensity ultrasonication, and high-hydrostatic pressure, was applied to improve the stability of sesame paste. Sesame protein addition reduced the phase separation by up to 48% in sesame paste compared to the sample (control) without protein addition, and also significantly enhanced the firmness and spreadability. With the addition of sesame protein isolate, the sesame paste samples formed a denser and more compact appearance. The flow characteristics of samples were better fitted by the Herschel-Bulkley equation, and modifying the added protein also played an essential role in improving the flow properties of sesame paste samples. Phase separation and oxidative stability of sesame paste were significantly improved by the addition of modified protein. Overall, the results indicated that sesame protein modified with HPH technology has a significant potential to improve the quality of sesame paste and prevent phase separation.

Identifying and optimization of critical process parameters for the modulation of polysaccharide molecular size in Streptococcus pneumoniae serotype-1

Maintaining the molecular size (MS) of Streptococcus pneumoniae capsular polysaccharide within specified range is essential for manufacture of conjugate vaccines, either through physical or acid hydrolysis before use in the conjugation process. Polysaccharide MS typically reduced, with high-pressure homogenization as an approach, for preserving their chemical structure. When the average MS of Pneumococcal capsular polysaccharide serotype-1(CPS1) exceeds 1200 kDa during fermentation, using a high-pressure homogenizer to reduce its MS to 150–250 kDa can become extremely difficult. Even after multiple homogenization cycles, obtaining polysaccharide of the required size can be challenging. Moreover, exceeding a certain number of homogenization cycles can negatively impact the stability, yield, and conjugation efficiency. To control polysaccharide MS, we conducted a design of experiments (DOE) study focused on the optimization of the fermentation process, employing serotype-1 as a represntative case. The successful optimization of these CPPs was achieved in a consistent and reproducible manner. Systematic evaluation by DOE based process optimization has provided valuable insights into precise polysaccharide manufacturing control of polysaccharide MS. Our findings confirm that maintaining Hy-Soy™ at 20-30 g/L and yeast extract at 1–3 g/L in the fermentation media, with a feed concentration of 2–3.5 g/L/H and 0.1–0.5 VVM of air, consistently yields polysaccharide with MS of < 1200 kDa. This strategy that can be extended to other S. pneumoniae serotype polysaccharide production.Graphical abstract

Flexible Cellulose Nanofiber (CNF)-Nano- Montmorillonite (MMT) Composite Sheet Structure and Water Vapor Barrier Performance

One of the newly developed nanomaterials for functioning as high-performance packaging materials to replace synthetic plastics such as low-density and high-density polyethylene (LDPE, HDPE) is cellulose nanofiber (CNF). These substances are biodegradable, recyclable, and renewable. While cellulose nanofiber-based films have substantially better water vapor permeability than traditional packaging polymers, they have extremely low oxygen permeability. Water vapor permeability (WVP) of the spray-coated composites was decreased via spraying nano-montmorillonite (MMT) content into CNF suspension and also high-pressure homogenization of CNF-MMT suspension. The process for spraying cellulose nanofiber (CNF)-nano-montmorillonite (MMT) suspension on the stainless-steel surface was developed to produce a high-barrier performance composite. The two types of composites were prepared via spraying of raw CNF with MMT and fibrillated CNF with MMT via high-pressure homogenization. The structure and barrier performance of these composites were investigated with SAXS and ASTM E96/E96M-05. Before homogenization, the MMT is agglomerated, while after homogenization it is more exfoliated, which is split up into individual sheets. The water vapor permeability could be reduced by adding up to 20 wt. % montmorillonite and dispersing montmorillonite with two passes in a high-pressure homogenizer. With montmorillonite addition above 20 wt. %, the water vapor permeability started to increase due to aggregation of the montmorillonite in the homogenized composite. At the optimal addition level, the best performance achieved with spraying was a water vapor permeability of 8.3 x 10-12 g/m.s.pa. The air permeability of the composite was evaluated to be less than 0.003 µm/Pa.s. This value confirms an impermeable composite for packaging applications. Considering the orientation of MMT in the composite, the composite’s structure can decide the barrier performance and can be altered by further fibrillation process of cellulose nanofibers via high-pressure homogenization.