Enhancing the efficacy of nano-curcumin on cancer cells through mixture design optimization of three emulsifiers.

Curcumin, a vital bioactive compound found naturally, has diverse biological applications. However, a major limitation of curcumin is its low bioavailability caused by its limited solubility in water. Hence, it is possible to overcome this problem through preparing oil in water nanodispersion of curcumin that emulsifier can play key role to produce nanodispersion. In the present study, the effect of three emulsifiers of Tween 80, Arabic Gum and Polyethylene glycol on preparing nanodispersions with desirable properties was investigated using subcritical water method and a mixture design. Zeta-potential and particle size of the achieved nanodispersions were taken into account as outcome factors. The optimum values for emulsifiers of Tween 80, Arabic Gum and Polyethylene glycol were obtained as 0.588 g, 0.639 g and 0.273 g, respectively, using the suggested model, so that obtained nanodispersion had minimum particle size (101.89 nm) and maximum zeta-potential (-24.99 mV). In fact, 102.5 nm and - 24.7 mV were obtained from experimental data at these values of emulsifiers. In addition, maximum loading potential (0.199 g/L), efficiency (99.5%), and minimum total curcumin loss (0.5%) were acquired at these optimum values. The results also show that the nanodispersion had a powerful antioxidant activity (65.27%) with extra antibacterial activity in facing with both E. coli and S. aureus strains. Moreover, curcumin nanodispersion was significantly taken up by HT-29 cells and resulted in the production of oxidative stress in the cells, leading to a decrease in the growth of cancer cells.

Lyophilized royal jelly preparation in nanoscale and evaluation of its physicochemical properties and bactericidal activity.

Royal jelly, due to its unique bioactive components, has special biological activities, but a great extent of its nutritional value is lost during processing and storage. Lyophilization, an effective preservation technique, can feasibly preserve the main bioactive compounds present in royal jelly. In this study, fresh royal jelly was subjected to the freeze-drying process at a pressure and temperature of 100 Pa and - 70°C, respectively, for 40 h. The results obtained indicated that the pH, turbidity, total phenol content, and antioxidant activity of the royal jelly powder (RJP), during 3 months of storage at ambient temperature (30°C), were constant with values of 4.30, 1.634 (%A.U.), 0.617 (g/L), and 28.7 (%), respectively. Moisture content of the prepared RJP was less than 1%, while that of the fresh royal jelly was 70%. Furthermore, for the fresh royal jelly, the mentioned parameters were significantly (p < .05) decreased after 2 months of storage at freezer temperature (-20°C). GC-MS analysis indicated that the amount of 10-hydroxy-2-decanoic acid (10H2DA) in RJP was 3.85 times more than that of fresh royal jelly. The obtained results also indicated that prepared RJP had a high bactericidal effect toward Escherichia coli and Staphylococcus aureus, with clear zone diameters of 12 and 15 mm, respectively. The present study provides a foundation for research on the potential application of prepared RJP and the development of dietary supplements and functional foods.

Enzymatically preparation of starch nanoparticles using freeze drying technique - Gelatinization, optimization and characterization.

Starch nanoparticles (SNPs) in colloidal forms were prepared using enzymatically pretreatment and four different gelatinization methods based on autoclave, microwave, ultrasonication and normal heating with stirring. Furthermore, SNPs in powder form were prepared using freeze drying technique. Results indicated that the formed SNPs using starch solution (1 % W/V) and ultrasonication technique had lowest mean particle size (151 nm) and PDI (0.173), and highest zeta potential (-8.8 mV) values. Optimization procedure using response surface methodology, based on central composite design, indicated that using 1.5 mL of α-amylase and sonication time of 15 min, SNPs with lowest particle size (49.3 nm) and highest zeta potential (-10.8 mV) were produced. Using prepared colloidal solution under optimal conditions, SNPs powder were produced by freeze dryer, adjusted at pressure and temperature of 100 Pa and - 70 °C, for 24 h. Results indicated that formed SNPs powder with squared-shape, had particle size, zeta potential, specific surface area, decomposition temperature of 197 nm, -13.9 mV, 1.9 m2g-1 and 162 °C, respectively. While, for native starch these values were 5018 nm, -6.01 mV, 0.68 m2g-1 and 170.2 °C, respectively. Results revealed that emulsification ability of SNPs powder was three times higher than that of the native starch.

Biogenic synthesis of gold nanoparticles using Artemia urumiana extract and five different thermal accelerated techniques: fabrication and characterization.

Artemia urumiana is bisexual population of the Lake Urmia of Iran. Its biomass was freeze dried and using its lyophilized powder, hydro-alcoholic extract was prepared and utilized in gold nanoparticles (Au NPs) synthesis. Six different Au NPs fabrication methods namely: microwave heating, hydrothermal, ultraviolet (UV) irradiation, ultrasonication, common heating using conventional heating, and self-assembling were utilized for Au NPs synthesis using A. urumiana extract. Gas chromatography analysis indicated that the prepared extract were contained numerous fatty acid methyl esters such as Hexadecanoic acid methyl ester. Results indicated that the formed NPs using heater and stirrer, and UV irradiation had minimum particle size of 25 and 94 nm, respectively. However, as compared to the formed Au NPs using heater and stirrer technique, UV irradiation fabricated Au NPs with high zeta potential value of -32.5 mV and small polydispersity value of 0.310. Results also demonstrated that the synthesized Au NPs using heater and stirrers, and UV irradiation had highest antioxidant activities of 13.7 and 11.9%, and bactericidal effects against Escherichia coli and Staphylococcus aurous bacteria strains, as compared to other fabricated Au NPs using other methods. There were insignificant (p > 0.05) differences between these two attributes of the formed Au NPs.

Developing three-component ginger-cinnamon-cardamom composite essential oil nanoemulsion as natural food preservatives.

Plant-based functional lipid ingredients, such as essential oils, with antioxidant and antibacterial activities, have gained substantial attention in food, cosmetic, and pharmaceutical formulations due to the increasing disquiet about the risks of artificial preservatives. However, similar to other lipid-based bioactives, their application in water-based products is challenging owing to their low water solubility and high chemical instability, especially during exposure to light, heat, moisture, and oxygen. Hence, the incorporation of essential oils into water-dispersible nanoemulsion systems can effectively address these issues. Moreover, combining various essential oils can synergistically enhance their chemical and biological properties. Consequently, the objective of this study was to develop different composite nanoemulsion systems using ginger, cinnamon, and cardamom essential oils, which were considered individually and in binary and ternary combinations. Empirical models to predict the response characteristics based on the proportions of oil phase components were also derived. The numerical multi-goal optimisation analysis suggested that 10 % ginger, 68 % cinnamon, and 22 % cardamom essential oil is the ideal oil phase combination to achieve nanoemulsions with the smallest average particle size and size distribution and the highest zeta potential and antioxidant and antibacterial activity.

Hydrothermally extraction of saponin from Acanthophyllum glandulosum root - Physico-chemical characteristics and antibacterial activity evaluation.

Saponin was extracted from Acanthophyllum glandulosum root under subcritical water conditions, and effects of root powder and pH of the solution were evaluated on the concentration of the saponin as manifested in its foamability and antioxidant activity using RSM. FT-IR analysis indicated that A. glandulosum root extract had 2 main functional groups (hydroxyl and amide I groups). Saponin with the highest foam height (4.66 cm), concentration (0.080 ppm) and antioxidant activity (90.6 %) was extracted using 10 g of the root powder and pH value of 4. Non-significant differences were observed between the predicted and experimental values of the extraction response variables. The study demonstrated good appropriateness of resulted models by Response Surface Methodology. Furthermore, higher values of R2 was attained for the foamability (>0.81) and antioxidant activity (>0.97), as well as large p-values (p > 0.05) indication of their lack-of-fit response verified the acceptable fitness of the provided models. The extracted saponin also showed bactericidal effect, which shows potential as a natural antibacterial compound.

Green approach in food nanotechnology based on subcritical water: effects of thyme oil and saponin on characteristics of the prepared oil in water nanoemulsions.

Thyme oil in water nanomulsion was prepared under subcritical water conditions using water and saponin, as solvent and emulsifier, respectively. Gas chromatography revealed that there were 44 bioactive components in the extracted thyme essential oil which, thymol and carvacrol were two mains of them. Experiments were designed based on central composite design and effects of amounts of saponin and thyme essential oil were evaluated on particle size, polydispersity index (PDI) and zeta potential of the prepared nanoemulsions using response surface methodology. Obtained results revealed that more desirable thyme oil nanoemulsions with minimum particle size (184.51 nm) and PDI (0.514), and maximum zeta potential (- 22.51 mV) were prepared using 0.94 g of saponin and 0.28 mL of thyme essential oil. Furthermore, results indicated that prepared nanoemulsion using obtained optimum production conditions had relatively high antioxidant activity (24%) and high antibacterial and antifungal activities against Staphylococcus aureus and Penicillium digitatum.

Effects of rotation speed and time, as solvent removal parameters, on the physico-chemical properties of prepared α-tocopherol nanoemulsions using solvent-displacement technique.

A bottom-up approach based on solvent-displacement technique was used to prepare α-tocopherol nanoemulsions. Effects of two main evaporation parameters namely, rotation speed (1 × 10-9 × 10 rpm) and rotation time (5-15 min) of utilized vacuum rotary evaporator, on the mean particle size, polydispersity index (PDI) and α-tocopherol degradation of the formed nanodroplets were evaluated using response surface methodology. Obtained results suggested three polynomial regression models for predicting the studied response variables' affected by selected evaporation parameters. Relatively high coefficients of determination for suggested models (> 0.7839) confirmed the suitability of the generated models. Multiple-optimization procedure revealed that the optimum amounts of evaporation speed and time were 30 rpm and 10 min, respectively, which in that, prepared spherical α-tocopherol nanoemulsions had mean particle size, PDI and concentration values of 48.9 nm, 0.232 and 358.7 mg/L, respectively.

Nanobiotechnology approach in intracellular selenium nanoparticle synthesis using Saccharomyces cerevisiae-fabrication and characterization.

Selenium nanoparticles (Se NPs) were synthesized using Saccharomyces cerevisiae yeast. Influences of different amounts of sodium selenite (5.0, 10.0, 15.0, 20.0, and 25 µg) were evaluated on growth of yeast during incubation at 32 °C, during 4 days. UV-Vis spectroscopy results have shown that synthesized Se NPs had broad emission peak (λmax) in the wavelength around 350 nm which demonstrated that formation of Se NPs occurred in intracellular manner. Physico-chemical characteristics of the synthesized Se NPs using dynamic light scattering particle-size analyzer indicated that the fabricated Se NPs had particle size, polydispersity index, and zeta potential ranging from 75 to 709 nm, 0.189 to 0989, and -7.06 to -10.3 mV, respectively. Obtained results revealed that intracellular Se NPs with minimum particle size (75 nm), maximum zeta potential (-10.3 mV), and antioxidant activity (48.5%) were synthesized using minimum amount of selenium salt (5 µg). However, most uniform Se NPs were formed using maximum amount of selenium salt (25 µg). Results also indicated that by increasing amount of sodium selenite in the culture media, from 5.0 to 25 µg, antioxidant activity of the formed Se NPs decreased from 48.5 to 20.8, respectively.

Optimization the formulation parameters in preparation of α-tocopherol nanodispersions using low-energy solvent displacement technique.

α-Tocopherol is the main compound of vitamin E with great antioxidant activity. However, like other functional lipid bioactive compounds, it suffers from low bioavailability due to its low water solubility and liable chemical structure. A bottom-up procedure based on a solvent-displacement method was constructed for fabrication of α-tocopherol nanodispersions using response surface methodology (RSM). The effects of main formulation parameters, namely, weight ratio of emulsifier to α-tocopherol and volumetric percent of acetone to water on the average particle size (nm), polydispersity index, concentration of α-tocopherol loss (% w/w) and turbidity of the nanodispersions were evaluated and optimized to gain the most desirable nanodispersions (least particle size, polydispersity index, turbidity and highest α-tocopherol concentrations). Second order regression equations, holding quite high coefficients of determination (R2 and adjusted R2 > 0.882), were significantly (p-value < 0.05) fitted for predicting the α-tocopherol nanodispersion characteristics variations as functions of studied formulation parameters. A multiple optimization analysis offered 6.5 and 10% for weight ratio of Tween 20 to α-tocopherol and volume percent of acetone, respectively, as overall optimum values for studied parameters. Statistically insignificant differences between experimental and predicted values of studied responses, verified the satisfactoriness of presented models for explaining the response characteristics as a function of formulation parameters. Thus, the employed solvent-displacement technique may provide the most desired water dispersible α-tocopherol nanoparticles for several water-based foods, cosmetic nutraceutical formulations.

Collagen modulates functional activity of hepatic cells inside alginate-galactosylated chitosan hydrogel microcapsules.

To provide comparable hepatic tissue microenvironment and induce functional behavior for hepatocytes, galctosylated-chitosan (GC) as well as collagen (Col) was added to alginate microcapsule coated with extra layer of chitosan. Four different hydrogel groups of alginate/chitosan (AC); alginate-galactosylated chitosan/chitosan (AGC/C); alginate-collagen/chitosan (ACol/C); and alginate-galactosylated chitosan-collagen/chitosan (AGCCol/C) were prepared and characterized for physical properties such as porosity, swelling, degradation rate, and stiffness. Introduction of GC as well as Col to alginate regulated significantly the physical properties of the resultant hydrogels. GC addition decreased dramatically swelling, degradation, pore size and mechanical properties of the resultant hydrogel. However, the influence of GC on the physical properties in the presence of Col (AGCCol/A) was in a reverse manner, as compared to the AGC/C hydrogel. The AGCCol/C microenvironment also promoted proliferation of microencapsulated HepG2 cells, as a model of hepatocyte, compared to the control-matched groups. Biochemical analysis after 10 days revealed a superior effect of AGCCol/C on the secretion of albumin and urea compared to other groups (P < 0.05). These features were coincided with the mRNA up-regulation of P450 and albumin in the AGCCol/C groups compared to the AGC/C and ACol/C groups (P < 0.05). The study demonstrated that enrichment of alginate-based hydrogels with Col and GC could be touted as an appropriate 3D platform for modular hepatic tissue engineering.

Microwave-Assisted Green Synthesis of Silver Nanoparticles Using Juglans regia Leaf Extract and Evaluation of Their Physico-Chemical and Antibacterial Properties.

Silver nanoparticles (Ag NPs) were synthesized using Juglans regia (J. regia) leaf extract, as both reducing and stabilizing agents through microwave irradiation method. The effects of a 1% (w/v) amount of leaf extract (0.1⁻0.9 mL) and an amount of 1 mM AgNO3 solution (15⁻25 mL) on the broad emission peak (λmax) and concentration of the synthesized Ag NPs solution were investigated using response surface methodology (RSM). Fourier transform infrared analysis indicated the main functional groups existing in the J. regia leaf extract. Dynamic light scattering, UV-Vis spectroscopy and transmission electron microscopy were used to characterize the synthesized Ag NPs. Fabricated Ag NPs with the mean particle size and polydispersity index and maximum concentration and zeta potential of 168 nm, 0.419, 135.16 ppm and -15.6 mV, respectively, were obtained using 0.1 mL of J. regia leaf extract and 15 mL of AgNO3. The antibacterial activity of the fabricated Ag NPs was assessed against both Gram negative (Escherichia coli) and positive (Staphylococcus aureus) bacteria and was found to possess high bactericidal effects.

ß-Carotene nanodispersions synthesis by three-component stabilizer system using mixture design.

In current research, simple centroid mixture design was applied to evaluate the interaction effects between three selected food grade stabilizers, namely, Tween 80, gelatine and pectin as stabilizing system in the formation of carotenoid nanoparticles through solvent displacement process. Both, particle size and ß-carotene loss of produced nanodispersions, as selected response factors, special cubic regression models with acceptable determination coefficient (>90%) was obtained. The multiple response optimization analysis showed that the overall optimum concentration for stabilizers will be 35% w/w Tween 80, 46% w/w gelatine and 19% w/w pectin, which led to the production of ß-carotene nanoparticles of spherical shape with minimum particle size of 155.8 nm and carotenoids loss of 25.3% w/w.

Chitosan magnetic nanoparticles for drug delivery systems.

The potential of magnetic nanoparticles (MNPs) in drug delivery systems (DDSs) is mainly related to its magnetic core and surface coating. These coatings can eliminate or minimize their aggregation under physiological conditions. Also, they can provide functional groups for bioconjugation to anticancer drugs and/or targeted ligands. Chitosan, as a derivative of chitin, is an attractive natural biopolymer from renewable resources with the presence of reactive amino and hydroxyl functional groups in its structure. Chitosan nanoparticles (NPs), due to their huge surface to volume ratio as compared to the chitosan in its bulk form, have outstanding physico-chemical, antimicrobial and biological properties. These unique properties make chitosan NPs a promising biopolymer for the application of DDSs. In this review, the current state and challenges for the application magnetic chitosan NPs in drug delivery systems were investigated. The present review also revisits the limitations and commercial impediments to provide insight for future works.

Application of magnetic nanoparticles in smart enzyme immobilization.

Immobilization of enzymes enhances their properties for efficient utilization in industrial processes. Magnetic nanoparticles, due to their high surface area, large surface-to-volume ratio and easy separation under external magnetic fields, are highly valued. Significant progress has been made to develop new catalytic systems that are immobilized onto magnetic nanocarriers. This review provides an overview of recent developments in enzyme immobilization and stabilization protocols using this technology. The current applications of immobilized enzymes based on magnetic nanoparticles are summarized and future growth prospects are discussed. Recommendations are also given for areas of future research.

Effects of homogenization process parameters on physicochemical properties of astaxanthin nanodispersions prepared using a solvent-diffusion technique.

Nanodispersion systems allow incorporation of lipophilic bioactives, such as astaxanthin (a fat soluble carotenoid) into aqueous systems, which can improve their solubility, bioavailability, and stability, and widen their uses in water-based pharmaceutical and food products. In this study, response surface methodology was used to investigate the influences of homogenization time (0.5-20 minutes) and speed (1,000-9,000 rpm) in the formation of astaxanthin nanodispersions via the solvent-diffusion process. The product was characterized for particle size and astaxanthin concentration using laser diffraction particle size analysis and high performance liquid chromatography, respectively. Relatively high determination coefficients (ranging from 0.896 to 0.969) were obtained for all suggested polynomial regression models. The overall optimal homogenization conditions were determined by multiple response optimization analysis to be 6,000 rpm for 7 minutes. In vitro cellular uptake of astaxanthin from the suggested individual and multiple optimized astaxanthin nanodispersions was also evaluated. The cellular uptake of astaxanthin was found to be considerably increased (by more than five times) as it became incorporated into optimum nanodispersion systems. The lack of a significant difference between predicted and experimental values confirms the suitability of the regression equations connecting the response variables studied to the independent parameters.

Application of chitosan-based nanocarriers in tumor-targeted drug delivery.

Cancer is one of the major malignant diseases in the world. Current anti tumor agents are restricted during the chemotherapy due to their poor solubility in aqueous media, multidrug resistance problems, cytotoxicity, and serious side effects to healthy tissues. Development of targeted drug nanocarriers would enhance the undesirable effects of anticancer drugs and also selectively deliver them to cancerous tissues. Variety of nanocarriers such as micelles, polymeric nanoparticles, liposomes nanogels, dendrimers, and carbon nanotubes have been used for targeted delivery of anticancer agents. These nanocarriers transfer loaded drugs to desired sites through passive or active efficacy mechanisms. Chitosan and its derivatives, due to their unique properties such as hydrophilicity, biocompatibility, and biodegradability, have attracted attention to be used in nanocarriers. Grafting cancer-specific ligands onto the Chitosan nanoparticles, which leads to ligand-receptor interactions, has been successfully developed as active targeting. Chitosan-conjugated components also respond to external or internal physical and chemical stimulus in targeted tumors that is called environment triggers. In this study, mechanisms of targeted tumor deliveries via nanocarriers were explained; specifically, chitosan-based nanocarriers in tumor-targeting drug delivery were also discussed.

Influence of small RNAs on biofilm formation process in bacteria.

Small non-coding RNAs (sRNAs) play a significant role in regulation of bacterial physiological behaviors. After sensing any environmental cue such as fluctuation of nutrient concentration, temperature, pH, and osmolarity, these sRNAs interfere to transmit these signals to target regulators and genes. sRNAs have key role in biofilm formation process by base pairing with target mRNAs or interaction with modulating proteins to both positive and negative regulation mechanisms. There are various regulatory systems to characterize the initiation and formation of special bacterial biofilms that are mostly described as two component systems based on sRNAs functions. In this study, regulatory pathways that are important for biofilm formation and genetic responses to environmental stimuli in mature biofilms were evaluated. Some of the regulatory systems that produce common types of biofilms such as curli, PGA, cellulose and polysaccharides such as alginate, colonic acid, Psl and their involved sRNAs functions were also discussed.