Characterization of Bacterial Nanocellulose - Graphite Nanoplatelets Composite Films

Bacterial cellulose (BC) was synthesized from pineapple peel extract media with addition of fermentation agent bacteria Acetobacter xylinum. BC was disintegrated from the pellicle into bacterial nanocellulose (BNC) by using a high-pressure homogenizer (hph) machine, which has a three-dimensional woven nanofibrous network. The synthesis of composite films started when BNC, graphite nanoplatelets, and cetyltrimethylammonium bromide (CTAB) were homogenized using an ultrasonic homogenizer then baked on a glass mold at a temperature of 80 degrees Celcius for 14h. A scanning electron microscope (SEM) was used to analyze its morphology. X-Ray diffraction spectra were used to analyze the composite films structure. The functional groups of the composite films were analyzed using the FTIR spectrum. SEM micrograph shows that GNP was evenly distributed into BNC matrix after CTAB addition. GNPs are shown as flat and smooth flakes with sharp corners. Some peak corresponds O-H, C-H, C≡C, and CH3 stretching was identified by using FTIR spectroscopy at wavenumber 3379, 2893, 2135, and 1340 cm-1, respectively. XRD analysis shows that Crystalline Index (C.I) of BNC increases after 2.5 wt% addition of GNP. The presence of CTAB decreases C.I value of composite films. BNC/GNP composite films have the best mechanical properties with Young’s modulus about 77.01 ± 8.564.

Scaling of Droplet Breakup in High-Pressure Homogenizer Orifices. Part II: Visualization of the Turbulent Droplet Breakup

Emulsion formation is of great interest in the chemical and food industry and droplet breakup is the key process. Droplet breakup in a quiet or laminar flow is well understood, however, actual industrial processes are always in the turbulent flow regime, leading to more complex droplet breakup phenomena. Since high resolution optical measurements on microscopic scales are extremely difficult to perform, many aspects of the turbulent droplet breakup are physically unclear. To overcome this problem, scaled experimental setups (with scaling factors of 5 and 50) are used in conjunction with an original scale setup for reference. In addition to the geometric scaling, other non-dimensional numbers such as the Reynolds number, the viscosity ratio and the density ratio were kept constant. The scaling allows observation of the phenomena on macroscopic scales, whereby the objective is to show that the scaling approach makes it possible to directly transfer the findings from the macro- to the micro-/original scale. In this paper, which follows Part I where the flow fields were compared and found to be similar, it is shown by breakup visualizations that the turbulent droplet breakup process is similar on all scales. This makes it possible to transfer the results of detailed parameter variations investigated on the macro scale to the micro scale. The evaluation and analysis of the results imply that the droplet breakup is triggered and strongly influenced by the intensity and scales of the turbulent flow motion.

Preparation of cationized albumin nanoparticles loaded indirubin by high pressure hemogenizer

Indirubin can be applied as an anti-cancer drug for inhibition of brain tumors. However, its performance is reduced due to hydrophobicity. In this study, we synthesized cationic human serum albumin (CHSA) nanoparticle by a new hybrid approach for improvement the surface chemistry of albumin and investigate the amount of indirubin loaded CHSA nanoparticle. In this study, the generated mechanical force from a high-pressure homogenizer (HPH) was used to make nanoparticles with a certain size with narrow polydispersity. The results indicated that the size of indirubin loaded CHSA nanoparticles were 130 nm and their zeta potential were +9. Besides, the encapsulation efficiency and drug loading capacity were found to be 85% and 5.8 %, respectively. To the best to our knowledge, this is the first time that indirubin has been used in albumin nanoparticles. In this study, indirubin loaded CHSA nanoparticles was shown can be a potential candidate for drug delivery in the treatment of glioblastoma. Moreover, the cationized form allows the chemical agent to be transmitted to the brain.

Characterization of Astaxanthin Nanoemulsions Produced by Intense Fluid Shear through a Self-Throttling Nanometer Range Annular Orifice Valve-Based High-Pressure Homogenizer

Stable, oil-in-water nanoemulsions containing astaxanthin (AsX) were produced by intense fluid shear forces resulting from pumping a coarse reagent emulsion through a self-throttling annular gap valve at 300 MPa. Compared to crude emulsions prepared by conventional homogenization, a size reduction of over two orders of magnitude was observed for AsX-encapsulated oil droplets following just one pass through the annular valve. In krill oil formulations, the mean hydrodynamic diameter of lipid particles was reduced to 60 nm after only two passes through the valve and reached a minimal size of 24 nm after eight passes. Repeated processing of samples through the valve progressively decreased lipid particle size, with an inflection in the rate of particle size reduction generally observed after 2–4 passes. Krill- and argan oil-based nanoemulsions were produced using an Ultra Shear Technology™ (UST™) approach and characterized in terms of their small particle size, low polydispersity, and stability.

Self-nano emulsifying drug delivery system: A versatile carrier for lipophilic drugs

Background: Lipid-based systems such as self-nano emulsifying drug delivery systems (SNEDDS) have resurged the eminence of nanoemulsions and offer many useful drug delivery opportunities. In the modern drug discovery era, there was a consistent increase in the number of poorly soluble new chemical entities which suffer from poor and erratic bioavailability problems. The oral route possesses some major disadvantages such as lack of constant drug levels in plasma, first-pass metabolism which results in poor bioavailability, so to address these problems, various lipid-based therapeutic systems are available from which (SNEDDS) have the promising tool for increasing the bioavailability of poorly soluble drugs. Methods: SNEDDS is the isotropic mixture of oils, surfactant, and co-surfactant having droplet size in the range of 100-200 nm, which spontaneously emulsifies when it contacts with aqueous media in Gastrointestinal (G.I) fluid. Various preparative methods are available for SNEDDS such as high-pressure homogenizer, Microfluidization, Sonication, Phase inversion, method. These methods show favorable benefits in drug delivery. SNEDDS possesses some disadvantages like precipitation of drug in G.I fluid or either drug will reach out in the capsule dosage form due to incompatibility issues, which will overcome by some more advanced techniques like supersaturate SNEDDS, which contains a precipitation inhibitor or Solid SNEDDS which will formulate either through spray drying or using a solid carrier. Conclusion: The lipid-based nanocarrier (SNEDDS) plays a significant role in drug delivery, to overcome the poor solubility and oral bioavailability. This review highlights the elaborative aspects of the diverse advantages of SNEDDS based formulations.

Effect of mono and diglyceride of medium chain fatty acid on the stability of flavour emulsion

Flavour emulsion is used in a wide range of food products including carbonated beverages, dairy products, confectionaries, and bakery products. Among its food applications are extensive uses in bakery products due to its high heat resistant properties. In flavour emulsion flavour oil is suspended in water phase and this water phase retains flavour even if such flavour emulsion is used for high temperature food application like baking. But flavour extracts are made by suspending flavour oil in alcohol. So, such flavour extracts are not suitable for high temperature food processing, since alcohol evaporates at high temperature. Thus, flavour emulsion is much better than flavour extracts. The stability of flavour emulsion depends on the emulsifier used in making flavour emulsion. Monocaprylin and dicaprylin are mono and diglyceride of mediumchain fatty acids having very good emulsifying properties. The stability of flavour emulsion can be improved by making use of mono and diglyceride as an emulsifier. The present study focused on the development of stable flavour emulsion from fruit waste using mono and diglyceride of medium-chain fatty acid as an emulsifier. The stable flavour emulsion is made from orange oil, water and emulsifier using ultra high-pressure homogenizer with 25 MPa pressure. Emulsifier mono and dicaprylin were synthesized by the esterification reaction between glycerol and caprylic acid. The effect of various combination of mono and dicaprylin is studied on the formation of stable flavour emulsion. The higher monocaprylin content in the emulsifier combination showed excellent results and a good synergistic effect on the stability of the emulsion. The combination of mono: diglyceride which resulted in the formation of stable flavour emulsion is 80:20 at 10% concentration, 2 passes and 25 mPa pressure in a high-pressure homogenizer. The stability of flavour emulsion was investigated using a storage study. The emulsion was found to be stable for 30 days at ambient temperature (25ºC) and refrigeration temperature (4ºC) but showed low stability at 50ºC.

Enzymatic Coupled Mechanical Defibrillation Process for the Production of Corn (Zea Mays) Cob Microfibrillated Cellulose: Preparation, Characterization and Evaluation as Pickering Emulsifier for Oil-In-Water Emulsion

Microfibrillated cellulose (MFC) is a type of nanocellulose having multiple functionalities. Typically, MFC was produced from mechanical high pressure homogenization process. However, this process is energy intensive and the fibrous nature of MFC often causes instrument blockage. The present study aims to utilize endoglucanse enzyme as environmentally friendly approach to pretreat fiber structure prior to undergoing mechanical defibrillation for the production of MFC from corn cob. Alkaline and bleached pretreated corn cob was treated with endoglucanase Fibercare R from 0% to 2.5% before passing through high pressure homogenizer. It was found that incorporation of 0.02% of endoglucanase was sufficient to soften the corn cob cellulose and further prevent the blockage of homogenizer. Subsequently, the 0.02% endoglucanse treated corn cob was passed through different cycles of homogenization from 0 cycle to 10 cycle for MFC production. It was observed that the water retention, zeta potential and shear viscosity of the MFC increases with homogenization cycle. MFC produced had a gel like consistency. Next, emulsifying stabilizing properties of MFC produced from cycle 0 to cycle 10 as well as their amount from 0 % to 1% were also assessed. Increase in homogenization cycle and the amount of MFC promote emulsion stability as observed from the low creaming index which is mainly attributed to the high shear viscosity and G’G’’ crossover of the emulsion. In all, the MFC derived from corn cob via enzymatic coupled with high pressure homogenization process has the potential to be used as gel like stabilizer in oil-in-water food emulsion system.

Making Concentrated Pterostilbene Highly Bioavailable in Pressure Processed Phospholipid Nanoemulsion

Pterostilbene, a dimethylether analog of resveratrol, has been found to have potent biological activity. However, the bioavailability of pterostilbene in the biological system is limited due to its poor solubility in an aqueous environment. A nanoemulsion system was designed for this purpose. Lecithin-based nanoemulsion was formed after 3 cycles through a high-pressure homogenizer at 500 psi. The rheological properties and particle size were measured using dynamic light scattering and a viscometer. The storage stabilities of the prepared formulation were determined based on its ability to maintain its particle size and loading concentration. According to the experimental results, the lecithin-based nanoemulsion system contained approximately 9.5% of pterostilbene. Over the 28-day stability test, the particle size, zeta potential, and encapsulation of pterostilbene in the nanoemulsion did not change significantly, indicating good storage stability. The positive effect of the prepared nanoemulsion system on bioavailability was studied and confirmed using in vitro lipolysis and a caco-2 monolayer model.