Tocotrienol has been shown to prevent bone loss in animal models of postmenopausal osteoporosis, but the low oral bioavailability might limit its use. A self-emulsifying drug delivery system (SEDDS) could increase the bioavailability of tocotrienol. However, evidence of this system in improving the skeletal effects of tocotrienol is scanty. This study aims to evaluate the therapeutic efficacy of annatto tocotrienol with SEDDS in a rat model of postmenopausal bone loss. Ten-month-old female Sprague Dawley rats were randomized into six groups. The baseline group was euthanatized at the onset of the study. Four other groups underwent ovariectomy to induce estrogen deficiency. The sham underwent similar surgery procedure, but their ovaries were retained. Eight weeks after surgery, the ovariectomized rats received one of the four different regimens orally daily: (a) SEDDS, (b) annatto tocotrienol [60 mg/kg body weight (b.w.)] without SEDDS, (c) annatto-tocotrienol (60 mg/kg b.w.) with SEDDS, (d) raloxifene (1 mg/kg b.w.). After eight weeks of treatment, blood was collected for the measurement of delta-tocotrienol level and oxidative stress markers. The rats were euthanized and their bones were harvested for the evaluation of the bone microstructure, calcium content and strength. Circulating delta-tocotrienol level was significantly higher in rats receiving annatto tocotrienol with SEDDS compared to the group receiving unformulated annatto-tocotrienol (p
Though the causes of Alzheimer's disease (AD) are yet to be understood, much evidence has suggested that excessive amyloid-β (Aβ) accumulation due to abnormal amyloid-β precursor protein (APP) processing and Aβ metabolism are crucial processes towards AD pathogenesis. Hence, approaches aiming at APP processing and Aβ metabolism are currently being actively pursued for the management of AD. Studies suggest that high cholesterol and a high fat diet have harmful effects on cognitive function and may instigate the commencement of AD pathogenesis. Despite the neuropharmacological attributes of black cumin seed (Nigella sativa) extracts and its main active compound, thymoquinone (TQ), limited records are available in relation to AD research. Nanoemulsion (NE) is exploited as drug delivery systems due to their capacity of solubilising non-polar active compounds and is widely examined for brain targeting. Herewith, the effects of thymoquinone-rich fraction nanoemulsion (TQRFNE), thymoquinone nanoemulsion (TQNE) and their counterparts' conventional emulsion in response to high fat/cholesterol diet (HFCD)-induced rats were investigated. Particularly, the Aβ generation; APP processing, β-secretase 1 (BACE1), γ-secretases of presenilin 1 (PSEN1) and presenilin 2 (PSEN2), Aβ degradation; insulin degrading enzyme (IDE), Aβ transportation; low density lipoprotein receptor-related protein 1 (LRP1) and receptor for advanced glycation end products (RAGE) were measured in brain tissues. TQRFNE reduced the brain Aβ fragment length 1-40 and 1-42 (Aβ40 and Aβ42) levels, which would attenuate the AD pathogenesis. This reduction could be due to the modulation of β- and γ-secretase enzyme activity, and the Aβ degradation and transportation in/out of the brain. The findings show the mechanistic actions of TQRFNE in response to high fat and high cholesterol diet associated to Aβ generation, degradation and transportation in the rat's brain tissue.
Engkabang fat esters were produced via alcoholysis reaction between Engkabang fat and oleyl alcohol, catalyzed by Lipozyme RM IM. The reaction was carried out in a 500 ml Stirred tank reactor using heptane and hexane as solvents. Response surface methodology (RSM) based on a four-factor-five-level Central composite design (CCD) was applied to evaluate the effects of synthesis parameters, namely temperature, substrate molar ratio (oleyl alcohol: Engkabang fat), enzyme amount and impeller speed. The optimum yields of 96.2% and 91.4% were obtained for heptane and hexane at the optimum temperature of 53.9°C, impeller speeds of 309.5 and 309.0 rpm, enzyme amounts of 4.82 and 5.65 g and substrate molar ratios of 2.94 and 3.39:1, respectively. The actual yields obtained compared well with the predicted values of 100.0% and 91.5%, respectively. Meanwhile, the properties of the esters show that they are suitable to be used as ingredient for cosmetic applications.
In this research we assess the feasibility of using palm oil agricultural refinery waste as a carbon source for the production of rhamnolipid biosurfactant through fermentation. The production and characterization of rhamnolipid produced by Pseudomonas aeruginosa PAO1 grown on palm fatty acid distillate (PFAD) under batch fermentation were investigated. Results show that P. aeruginosa PAO1 can grow and produce 0.43gL(-1) of rhamnolipid using PFAD as the sole carbon source. Identification of the biosurfactant product using mass spectrometry confirmed the presence of monorhamnolipid and dirhamnolipid. The rhamnolipid produced from PFAD were able to reduce surface tension to 29mNm(-1) with a critical micelle concentration (CMC) 420mgL(-1) and emulsify kerosene and sunflower oil, with an emulsion index up to 30%. Results demonstrate that PFAD could be used as a low-cost substrate for rhamnolipid production, utilizing and transforming it into a value added biosurfactant product.
A new approach to recover microalgae from aqueous medium using a bio-flotation method is reported. The method involves utilizing a Moringa protein extract - oil emulsion (MPOE) for flotation removal of Nannochloropsis sp. The effect of various factors has been assessed using this method, including operating parameters such as pH, MPOE dose, algae concentration and mixing time. A maximum flotation efficiency of 86.5% was achieved without changing the pH condition of algal medium. Moreover, zeta potential analysis showed a marked difference in the zeta potential values when increase the MPOE dose concentration. An optimum condition of MPOE dosage of 50ml/L, pH 8, mixing time 4min, and a flotation efficiency of greater than 86% was accomplished. The morphology of algal flocs produced by protein-oil emulsion flocculant were characterized by microscopy. This flotation method is not only simple, but also an efficient method for harvesting microalgae from culture medium.
Encapsulating fish oil by spray drying with an adequate wall material was investigated to determine if stable powders containing emulsified fish-oil-droplets can be formed. In particular, the dextrose equivalent (DE) of maltodextrin (MD) affects the powder structure, surface-oil ratio, and oxidative stability of fish oil. The carrier solution was prepared using MD with different DEs (DE = 11, 19, and 25) and sodium caseinate as the wall material and the emulsifier, respectively. The percentage of microcapsules having a vacuole was 73, 39, and 38% for MD with DE = 11, 19, and 25, respectively. Peroxide values (PVs) were measured for the microcapsules incubated at 60 °C. The microcapsules prepared with MD of DE = 25 and 19 had lower PVs than those prepared with MD of DE = 11. The difference in PV can be ascribed to the difference in the surface-oil ratio of the spray-dried microcapsules.
Formulations containing engkabang fat and engkabang fat esters, F10 and E15 respectively were prepared using a high-shear homogenizer, followed by a high-pressure homogenizer. Both formulations were stable at room temperature, at 45 degrees C, and after undergoing freeze-thaw cycles. The particle sizes of F10 and E15 after high pressure were 115.75 nm and 148.41 nm respectively. The zeta potentials of F10 and E15 were -36.4 mV and -48.8 mV respectively, while, the pH values of F10 and E15 were 5.59 and 5.81 respectively. The rheology of F10 and E15 showed thixotropy and pseudoplastic behavior respectively. There were no bacteria or fungal growths in the samples. The short-term moisturizing effect on 20 subjects analyzed by analysis of variance (ANOVA), gave p-values of 7.35 x 10(-12) and 2.77 x 10(-15) for F10 and E15 respectively. The hydration of the skins increased after application of F10 and E15 with p-value below 0.05.
Kraft lignin (KL) is a renewable source of many valuable intermediate biochemical products currently derived from petroleum. An excessive of lignin comes from pulping wastewater caused an adverse pollution problems hence affecting human and aquatic life. A comprehensive study pertaining to emulsion liquid membrane (ELM) extraction of lignin from pulping wastewater was presented. ELM formulation contains Aliquat 336 as carrier, kerosene as diluent, sodium bicarbonate (NaHCO3 ) as stripping agent and Span 80 as surfactant. The emulsion stability was investigated at different surfactant concentrations, homogenizer speed and emulsification time. Modifier (2-ethyl-1-hexanol) was added to avoid segregation of third phase while improving the emulsion stability. At optimum conditions, 95% and 56% of lignin were extracted and recovered, respectively at 10 min of extraction time, 0.007 M of Aliquat 336, 0.1 M of NaHCO3 and 1:5 of treat ratio. Additional of modifier was contributed to highest recovery up to 98%. The ELM process was found to be equally feasible and quite effective in the recovery of KL from real pulping wastewater. Therefore, ELM process provides a promising alternative technology to recover KL from pulping wastewater while solving the environmental problems simultaneously.
The commercial application of liquid-state Pickering emulsions in food systems remains a major challenge. In this study, we developed a spray-dried Pickering emulsion powder using chitosan as a Pickering emulsifier and alginate as a coating material. The functionality of the powder was evaluated in terms of its oxidative stability, pH-responsiveness, mucoadhesivity, and lipid digestibility. The Pickering emulsion powder was oxidatively more stable than the conventional emulsion powder stabilized by gum Arabic. The powder exhibited pH-responsiveness, whereby it remained intact in acidic pH, but dissolved to release the emulsion in 'Pickering form' at near-neutral pH. The Pickering emulsion powder was also mucoadhesive and could be digested by lipase in a controlled manner. These findings suggested that the multi-functional Pickering emulsion powder could be a potential delivery system for applications in the food industry.
Acetylated, propionylated and butyrylated rice and quinoa starches at different levels of modification and starch concentrations, were used to stabilize oil-in-water starch Pickering emulsions at 10% oil fraction. Short-chain fatty acid modified starch Pickering emulsions (SPEs) were characterized after emulsification and after 50 days of storage. The particle size distribution, microstructure, emulsion index, and stability were evaluated. An increase in starch concentration led to a decrease of emulsion droplet sizes. Quinoa starch has shown the capability of stabilizing Pickering emulsions in both the native and modified forms. The emulsifying capacity of SPEs was improved by increasing the chain length of SCFA. Modified quinoa starch with higher chain lengths (i.e. propionylated and butyrylated), at higher levels of modification, showed higher emulsion index (>71%) and stability over the entire 50 days storage. At optimized formulation, SCFA-starch particles have the potential in stabilizing emulsions for functional foods, pharmaceutical formulations, or industrial food applications.
Chitin biopolymer has received significant attention recently by many industries as a green technology. Nanotechnology has been used to make chitin nanocrystals (ChiNCs) that are rod-shaped natural nanomaterials with nanoscale size. Owing to the unique features such as biodegradability, biocompatibility, renewability, rod-shape, and excellent surface and interfacial, physiochemical, and thermo-mechanical properties; ChiNCs have been green and attractive products with wide applications specifically in medical and pharmaceutical, food and packaging, cosmetic, electrical, and electronic, and also in the oil and gas industry. This review aims to give a comprehensive and applied insight into ChiNCs technology. It starts with reviewing different sources of chitin and their extraction methods followed by the characterization of ChiNCs. Furthermore, a detailed investigation into various complex fluids (dispersions, emulsions, foams, and gels) stabilized by ChiNCs and their characterisation have been thoroughly deliberated. Finally, the current status including ground-breaking applications, untapped investigations, and future prospective have been presented.
The potential of ultrasonication-driven molecular self-assembly of whey protein isolate (WPI) with chitosan (CS)/chitooligosaccharide (COS) to stabilize Pickering emulsions was examined, based on CS/COS ligands-induced partial unfolding in remodeling the Pickering particles features. Multi-spectral analysis suggested obvious changes in conformational structures of WPI due to interaction with CS/COS, with significantly higher unfolding degrees of WPI induced by COS. Non-covalent interactions were identified as the major forces for WPI-CS/COS conjugates. Ultrasonication enhanced electrostatic interaction between CS's -NH3 groups and WPI's -COO- groups which improved emulsification activity and storability of WPI-COS stabilized Pickering emulsion. This was attributed to increased surface hydrophobicity and decreased particle size compared to WPI-CS associated with differential unfolding degrees induced by different saccharide ligands. CLSM and SEM consistently observed smaller emulsion droplets in WPI-COS complexes than WPI-CS/COS particles tightly adsorbed at the oil-water interface. The electrostatic self-assembly of WPI with CS/COS greatly enhanced the encapsulation efficiency of quercetin than those stabilized by WPI alone and ultrasound further improved encapsulation efficiency. This corresponded well with the quantitative affinity parameters between quercetin and WPI-CS/COS complexes. This investigation revealed the great potential of glycan ligands-induced conformational transitions of extrinsic physical disruption in tuning Pickering particle features.
The development of hybrid polysaccharide-protein complexes as Pickering emulsion stabilizers has attracted increasing research interest in recent years. This work presents an eco-friendly surface modification strategy to functionalize hydrophilic cellulose nanocrystals (CNC) using hydrophobic soy protein isolate (SPI) via mussel adhesive-inspired poly (l-dopa) (PLD) to develop improved nanoconjugates as stabilizers for oil-in-water Pickering emulsion. The physicochemical properties of the CNC-PLD-SPI nanoconjugate were evaluated by solid-state 13C NMR, FT-IR, TGA, XRD, contact angle analysis, and TEM. The modified CNC (conjugation content of 38.22 ± 1.21%) had lowered crystallinity index, higher thermal stability, and more hydrophobic than unmodified CNC, with an average particle size of 309.9 ± 8.0 nm. Use of amphiphilic CNC-PLD-SPI nanoconjugate with greater conformational flexibility as Pickering stabilizer produced oil-in-water emulsions with greater physical stability.
Oxidative stress is intensely involved in enhancing the severity of various chronic respiratory diseases (CRDs) including asthma, chronic obstructive pulmonary disease (COPD), infections and lung cancer. Even though there are various existing anti-inflammatory therapies, which are not enough to control the inflammation caused due to various contributing factors such as anti-inflammatory genes and antioxidant enzymes. This leads to an urgent need of novel drug delivery systems to combat the oxidative stress. This review gives a brief insight into the biological factors involved in causing oxidative stress, one of the emerging hallmark feature in CRDs and particularly, highlighting recent trends in various novel drug delivery carriers including microparticles, microemulsions, microspheres, nanoparticles, liposomes, dendrimers, solid lipid nanocarriers etc which can help in combating the oxidative stress in CRDs and ultimately reducing the disease burden and improving the quality of life with CRDs patients. These carriers improve the pharmacokinetics and bioavailability to the target site. However, there is an urgent need for translational studies to validate the drug delivery carriers for clinical administration in the pulmonary clinic.
The study determined the effect of thymoquinone rich fraction (TQRF) and thymoquinone (TQ) in the forms of nano- and conventional emulsions on learning and memory, lipid peroxidation, total antioxidant status, antioxidants genes expression and soluble β-amyloid (Aβ) levels in rats fed with a high fat-cholesterol diet (HFCD). The TQRF was extracted from Nigella sativa seeds using a supercritical fluid extraction system and prepared into nanoemulsion, which later named as TQRF nanoemulsion (TQRFNE). Meanwhile, TQ was acquired commercially and prepared into thymoquinone nanoemulsion (TQNE). The TQRF and TQ conventional emulsions (CE), named as TQRFCE and TQCE, respectively were studied for comparison. Statin (simvastatin) and non-statin (probucol) cholesterol-lowering agents, and a mild-to-severe Alzheimer's disease drug (donepezil) were served as control drugs. The Sprague Dawley rats were fed with HFCD for 6 months, and treated with the intervention groups via oral gavage daily for the last 3 months. As a result, HFCD-fed rats exhibited hypercholesterolaemia, accompanied by memory deficit, increment of lipid peroxidation and soluble Aβ levels, decrement of total antioxidant status and down-regulation of antioxidants genes expression levels. TQRFNE demonstrated comparable effects to the other intervention groups and control drugs in serum biomarkers as well as in the learning and memory test. Somehow, TQRFNE was more prominent than those intervention groups and control drugs in brain biomarkers concomitant to gene and protein expression levels. Supplementation of TQRFNE into an HFCD thus could ameliorate memory deficit, lipid peroxidation and soluble Aβ levels as well as improving the total antioxidant status and antioxidants genes expression levels.
The groundbreaking innovation and industrialization are ushering in a new era where technology development is integrated with the sustainability of materials. Over the decade, nanocrystalline cellulose (NCC) obtained from lignocellulosic biomass had created a great value in various aspects. The abundantly available empty fruit bunch (EFB) in the palm oil industry has motivated us to utilize it as a sustainable alternative for the isolation of NCC, which is a worthwhile opportunity to the waste management of EFB. Taking advantage of the shape anisotropy and amphiphilic character, NCC has been demonstrated as a natural stabilizer for oil-in-water emulsion. In this work, preparation of highly stable Pickering nanoemulsion using black cumin seed oil and NCC was attempted. Black cumin seed oil is a class of plant oil with various nutritional and pharmaceutical benefits. However, its poor solubility could substantially lower the therapeutic effect, and thus, requires a delivery system to overcome this limitation. The role of NCC in the formation of stable Pickering nanoemulsion was investigated. The emulsification process was found crucial to the resulting droplet size, whereas NCC contributed critically to its stabilization. The droplet size obtained from ultrasonication and microfluidization was approximately 400 nm, as examined using transmission electron microscopy. The droplet (oil-to-water = 2:8) has long-term stability against creaming and coalescence for more than six months. The nanoemulsion stabilized by NCC could allow a better absorption by the human body, thereby maximizing the potential of black cumin seed oil in the personal care and food industries.
A series of sugar-based surfactants, involving a single hydrophobic chain (C12) and two side-by-side arranged head groups, was prepared form simple glucose precursors. All surfactants were highly water soluble and exhibited exclusively micellar assemblies. This behavior makes them interesting candidates for oil in water emulsifiers.
The effect of incorporating new nonionic glycolipid surfactants on the properties of a model water/nonionic surfactant/oil nano-emulsion system was investigated using branched-chain alkyl glycosides: 2-hexyldecyl-β(/α)-D-glucoside (2-HDG) and 2-hexyldecyl-β(/α)-D-maltoside (2-HDM), whose structures are closely related to glycero-glycolipids. Both 2-HDG and 2-HDM have an identical hydrophobic chain (C16), but the former consists a monosaccharide glucose head group, in contrast to the latter which has a disaccharide maltose unit. Consequently, their hydrophilic-lipophilic balance (HLB) is different. The results obtained have shown that these branched-chain alkyl glycosides affect differently the stability of the nano-emulsions. Compared to the model nano-emulsion, the presence of 2-HDG reduces the oil droplet size, whereas 2-HDM modify the properties of the model nano-emulsion system in terms of its droplet size and storage time stability at high temperature. These nano-emulsions have been proven capable of encapsulating ketoprofen, showing a fast release of almost 100% in 24h. Thus, both synthetically prepared branched-chain alkyl glycosides with mono- and disaccharide sugar head groups are suitable as nano-emulsion stabilizing agents and as drug delivery systems in the future.
Palm kernel oil esters nanoemulsion-loaded with chloramphenicol was optimized using response surface methodology (RSM), a multivariate statistical technique. Effect of independent variables (oil amount, lecithin amount and glycerol amount) toward response variables (particle size, polydispersity index, zeta potential and osmolality) were studied using central composite design (CCD). RSM analysis showed that the experimental data could be fitted into a second-order polynomial model. Chloramphenicol-loaded nanoemulsion was formulated by using high pressure homogenizer. The optimized chloramphenicol-loaded nanoemulsion response values for particle size, PDI, zeta potential and osmolality were 95.33nm, 0.238, -36.91mV, and 200mOsm/kg, respectively. The actual values of the formulated nanoemulsion were in good agreement with the predicted values obtained from RSM. The results showed that the optimized compositions have the potential to be used as a parenteral emulsion to cross blood-brain barrier (BBB) for meningitis treatment.
The present work was conducted to investigate the effect of purification and conjugation processes on functional properties of durian seed gum (DSG) used for stabilization of water in oil in water (W/O/W) emulsion. Whey protein isolate (WPI) was conjugated to durian seed gum through the covalent linkage. In order to prepare WPI-DSG conjugate, covalent linkage of whey protein isolate to durian seed gum was obtained by Maillard reaction induced by heating at 60 °C and 80% (±1%) relative humidity. SDS-polyacrylamide gel electrophoresis was used to test the formation of the covalent linkage between whey protein isolate and durian seed gum after conjugation process. In this study, W/O/W stabilized by WPI-conjugated DSG A showed the highest interface activity and lowest creaming layer among all prepared emulsions. This indicated that the partial conjugation of WPI to DSG significantly improved its functional characteristics in W/O/W emulsion. The addition of WPI-conjugated DSG to W/O/W emulsion increased the viscosity more than non-conjugated durian seed gum (or control). This might be due to possible increment of the molecular weight after linking the protein fraction to the structure of durian seed gum through the conjugation process.