Encapsulation Efficiency Of Quercetin Research Articles

Targeted delivery of quercetin using gelatin/starch/Fe3O4 nanocarrier to suppress the growth of liver cancer HepG2 cells

To suppress HepG2 liver cancer cells, a nanocarrier (NC) consisting of Fe3O4, Gelatin (G), and Starch (S) was synthesized and characterized for targeted delivery of Quercetin (QC) drug. The spectra obtained from X-ray diffraction (XRD) and Fourier transform infrared (FTIR) demonstrated that the nanoparticles (NP) in the NC are well-interconnected to each other and have formed a regular structure. Also, field emission scanning electron microscopy (FE-SEM) indicates a smooth and homogeneous surface of the synthesized NC. The results of the vibrating sample magnetometer (VSM) also corroborated the correctness of the synthesis of Fe3O4 NPs and Gelatin/Starch/Fe3O4@Quercetin NC (G/S/Fe3O4@QC) because the magnetic properties of Fe3O4 decreased with the addition of G/S@QC. Stability and particle size were determined by zeta potential and Dynamic light scattering (DLS). The percentage of drug loading and encapsulation efficiency of QC in the NC was 46.25 % and 87 %, respectively. QC profile release in acidic and natural environments showed controlled release and pH sensitivity of the NC. Cytotoxicity of L929 and HepG2 treated cells with the G/S/Fe3O4@QC was investigated by MTT staining, which agreed with the flow cytometry result. The results of Flowcytometry and MTT showed 43.5 % apoptosis and 42 % cytotoxicity in treated HepG2 cells by G/S/Fe3O4@QC, while it was not toxic to L929 normal cells. According to the results, G/S/Fe3O4@QC is a suitable NC for the targeted delivery of QC as a drug against HepG2 cancer cells.

O1/W/O2 double emulsion gels based on nanoemulsions and Pickering particles for co-encapsulating quercetin and cyanidin: A functional fat substitute

An O1/W/O2 double emulsion gel, as a functional fat substitute and based on nanoemulsions and hydrophobic Pickering particles, is prepared by two-step emulsification to co-encapsulate hydrophilic cyanidin and hydrophobic quercetin. Nanoemulsions loading quercetin are fabricated by Tween-80 and combining high-speed and high-pressure emulsification. Phytosterol nanoparticles stabilize the W-O2 interface of the secondary emulsion to load cyanidin in the W phase. The concentration of Tween-80 is optimized as 0.3% by the droplet size and viscosity of nanoemulsions. The structural stability of double emulsion gels will be weakened along with the increase of nanoemulsions, showing lower modulus and encapsulation efficiency (EE) and bigger droplets. In double emulsion gels, the EE of quercetin and cyanidin reaches 93% and 85.6%, respectively. Analysis of molecular interaction indicates that Tween-80 would decrease the in-situ hydrophobicity of phytosterol nanoparticles by hydrogen bonding adsorption, thereby weakening the emulsification. The pH-chromic 3D printing of double emulsion gels is designed according to the pH sensitivity of cyanidin. Texture profile analysis is performed to test the textural properties of 3D-printed objects. The simulated digestion is conducted on double emulsion gels. The double emulsion gel with fewer nanoemulsions is beneficial for protecting quercetin and improving the delivery due to the higher structural stability, while that with more nanoemulsions is conducive to the digestion of cyanidin and camellia oil due to weakened semi-solid properties. This double emulsion gel further simulates fat tissues by co-encapsulating hydrophilic and hydrophobic substances, promoting the application of fat substitutes in the food industry.

Preparation of starch-based nanoemulsion for sustained release and enhanced bioaccessibility of quercetin

Quercetin is an essential flavonoid with various activities, but it has low bioaccessibility and poor stability. In the present study, an oil-in-water nanoemulsion stabilized by octenyl succinic anhydride modified starch (OSA-CS) was prepared for the delivery, controlled release, enhanced bioaccessibility of quercetin and probing the release mechanism of quercetin from the emulsion in the gastrointestinal tract. OSA-CS with higher substitution than commercially available starch was prepared, and quercetin-loaded nanoemulsions with good storage stability were prepared using it as an emulsifier. The encapsulation efficiency of quercetin in this emulsion was 80.3%, and the loading efficiency was 48.8%, higher than the current study. The release mechanism and bioaccessibility of the starch-based quercetin emulsion during in vitro digestion were explored using in vitro oral, gastric, and intestinal digestion models, and the in vivo delivery ability of the quercetin emulsion was verified in mouse experiments. The release of quercetin from the nanoemulsion in the gastrointestinal tract had the highest fit with the Korsmeyer–Peppas model (R2 > 0.99) and had a high fit with the Higuchi model (R2 = 0.8651), suggesting that diffusion and erosion were the primary release mechanisms. In vivo experiments showed that the nanoemulsions prepared in this study had good quercetin delivery properties. The delivery system substantially improved the bioaccessibility of quercetin from 1.90% to 13.4%, which was superior to other emulsion systems.

Hydrolytic Quinoa Protein and Cationic Lotus Root Starch-Based Micelles for Co-Delivery of Quercetin and Epigallo-catechin 3-Gallate in Ulcerative Colitis Treatment.

The accumulation and sustained release of drugs in the colonic inflammatory region are the favorable strategy for treating ulcerative colitis (UC). In this study, we developed a synergistic anti-inflammatory drug (quercetin/EGCG)-loaded micelle using hydrolytic quinoa protein (HQP) and cationic lotus root starch (CLRS) by a layer-by-layer assembly method. The encapsulation efficiency of quercetin and EGCG in the Que-HQP-EGCG-CLRS micelles reached 91.5 and 89.4%, respectively. This composite micelle exhibited a core-shell structure, where Que-HQP-EGCG was the core and CLRS was the coating shell. Moreover, the in vitro experiments indicated that these micelles can make Que/EGCG pass through gastric environments stably and delay their release in the intestine. Animal experiments further confirmed that the Que-HQP-EGCG-CLRS micelles can efficiently accumulate in the colonic inflammatory region and enable sustained release of drugs (more than 24 h), thus notably alleviating the symptoms of UC. These results suggested that Que-HQP-EGCG-CLRS micelles have good gastric stability, colonic inflammatory-accumulated effect, and sustained drug release ability, which are a promising co-delivery system for UC treatment.

Development of Poly(lipoic acid) Nanoparticles with Improved Oral Bioavailability and Hepatoprotective Effects of Quercetin.

Quercetin (QUE)-loaded poly(lipoic acid) nanoparticles (QUE/pLA) were developed to improve chemical stability in the gastrointestinal (GI) tract, oral bioavailability (BA), and pharmacological properties of QUE. QUE/pLA was prepared by emulsion solvent evaporation with ultrasonication followed by freeze-drying. Its mean particle size was 185 nm, with a high encapsulation efficiency of QUE (84.8%). QUE/pLA exhibited sustained release of QUE with improved dissolution compared with crystalline QUE and significantly enhanced chemical stability under physiological pH in the GI tract. Orally dosed QUE/pLA (50 mg QUE/kg) in rats exhibited significantly prolonged systemic exposure, possibly due to the sustained release of QUE. The oral BAs of QUE in QUE/pLA and crystalline QUE groups were 29 and 0.19%, respectively, suggesting significant enhancement of oral absorbability, likely due to the improved stability and dissolution property of QUE in the GI tracts. In hepatic injury model rats, QUE/pLA (50 mg QUE/kg) led to marked reductions in the plasma biomarker levels of alanine aminotransferase and aspartate aminotransferase by 70 and 46%, respectively, compared with the vehicle group. QUE/pLA also showed improved antioxidant potential as evidenced by the enhanced activities of hepatic glutathione, superoxide dismutase, and a decrease in the level of malondialdehyde, a marker of lipid peroxidation. Based on these findings, QUE/pLA might be a promising option to improve both the nutraceutical and pharmaceutical properties of QUE.

Caseinate nanoparticles co-loaded with quercetin and avenanthramide 2c using a novel two-step pH-driven method: Formation, characterization, and bioavailability

The pH-driven method is a green and efficient encapsulation technology to incorporate hydrophobic polyphenols. However, this method has never been used to prepare nanoparticles loaded with multiple polyphenols of different water solubility and chemical stability. In the present study, the pH-dependent water solubility and chemical stability of quercetin and avenanthramide 2c (AV 2c) were characterized to develop a novel two-step pH-driven method to co-load quercetin and AV 2c in sodium caseinate (NaCas) nanoparticles (Q-2c-N). Quercetin-loaded NaCas nanoparticles (QNN) were fabricated by increasing the mixture to pH 12.0, followed by acidification to pH 7.0. Subsequently, AV 2c was dissolved in the QNN dispersion that was further acidified to pH 6.0 to prepare Q-2c-N. The encapsulation efficiency of quercetin and AV 2c in the Q-2c-N was up to 94.3% and 80.6%, respectively, and remained stable in 21 days at 21 °C. Based on solubility, particle structure, zeta potential, and fluorescence spectroscopy assays, molecular binding between NaCas and deprotonated quercetin was critical to quercetin encapsulation during acidification to pH 7.0, and the gradual loss of AV 2c solubility during further pH adjustment to 6.0 enabled the embedment of AV 2c in QNN to form Q-2c-N with reduced particle size. Moreover, quercetin and AV 2c were almost molecularly distributed in Q-2c-N based on XRD patterns and FT-IR spectra. Co-loading quercetin and AV 2c in Q-2c-N significantly improved the bioaccessibility and Caco-2 cell monolayer uptake. The present study may be significant to the utilization of polyphenols with distinctly different physical properties.

Development and evaluation of delivery systems for quercetin: A comparative study between coarse emulsion, nano-emulsion, high internal phase emulsion, and emulsion gel

This study aimed to identify the most suitable delivery system for quercetin. To achieve this objective, four delivery systems, i.e., coarse emulsions, nano-emulsions, high internal phase emulsions (HIPEs), and emulsion gels, were prepared and characterized by structure, rheology, stability, and bioaccessibility. The nano-emulsion exhibited the smallest particle size, highest absolute ζ-potential, and best thermal stability and storage stability. The HIPEs showed the best freeze-thaw and oxidative stability. Regarding rheology, all delivery systems exhibited elastic gel-like behavior, which consistent to the characteristics of non-Newtonian fluids. The encapsulation efficiencies of quercetin in these delivery systems were greater than 81.56%. The lowest rate of free fatty acid release was observed in the HIPEs, and the highest bioaccessibilities of quercetin were observed in the nano-emulsion and emulsion gel. Thus, the nano-emulsion is the most suitable for the delivery of quercetin among the four delivery systems. • Coarse emulsion, nano-emulsion, HIPEs, and emulsion gel were fabricated. • The encapsulation efficiency of quercetin in these delivery systems was >81.56%. • HIPEs decreased the release rate of FFA during in vitro simulated digestion. • The nano-emulsion and emulsion gel exhibited the highest bioaccessibilities. • The nano-emulsion was the most suitable for the delivery of quercetin.

Quercetin loaded PLGA microspheres induce apoptosis in breast cancer cells

Quercetin is well known for its effective inhibition of cancer cell proliferation by inducing the apoptosis. In the present study, quercetin isolated from Allium cepa were loaded on a biodegradable polymer, poly(lactic-co-glycolic acid) (PLGA) microspheres and its apoptotic potential in Michigan Cancer Foundation (MCF-7) cell was investigated. PLGA microspheres before and after loading indicated no significant difference in size as the average size of the microspheres were 100 μm. The encapsulation efficiency of quercetin on PLGA was found to be 74 ± 1.2%. Cytotoxicity and flow cytometric analysis were used to evaluate the capacity of quercetin-PLGA microspheres (PLGAq) on anticancer activity. PLGAq were assessed at two different concentrations (1.5 μg and 3.0 μg) and indicated that at higher concentrations it showed effective inhibition of cancer cells. The results indicated that the PLGAq microspheres efficiently inhibit cell proliferation by inducing the apoptosis demonstrating that the biodegradable PLGAq microspheres will provide a promising therapeutic approach for the treatment of breast cancer.

Synergistic anticancer effect of green synthesized nickel nanoparticles and quercetin extracted from Ocimum sanctum leaf extract

Leaf extract of medicinally important plant Ocimum sanctum (O. sanctum) has been used for the synthesis of nickel nanoparticles (NiGs) and extraction of quercetin (Qu). Qu has been conjugated with NiGs for enhanced anticancer effect on human breast cancer MCF–7 cells. Extracted Qu was conjugated with polyethylene glycol (PEG) coated NiGs (Qu–PEG–NiGs) which was used as carriers for breast cancer treatment. Anticancer activity of Qu–PEG–NiGs was evaluated by assessing cell viability, reactive oxygen species (ROS) production, caspase activity, mitochondrial membrane potential (MMP) and changes in nuclear morphology (staining methods). 0.85mg of quercetin was extracted from 1g of leaves with retention time (Rt) of 2.914min. Loading and encapsulation efficiency of quercetin onto PEG–NiGs was 15.04% and 82% respectively and Qu–PEG–NiGs has shown a sustained release of Qu of about 84% after 48h. Qu and Qu–PEG–NiGs showed dose dependent (1.56–50μg/mL) anticancer effect against MCF–7 cells with IC50 values of 50 and 6.25μg/mL respectively which was mediated by oxidative stress due to ROS over-production that induced loss of mitochondrial membrane potential, capsase -9, -7 activities leading to apoptosis. The present study validates that Qu–PEG–NiGs can be used as a potential anticancer agent for cancer therapy.

Microchannel emulsification study on formulation and stability characterization of monodisperse oil-in-water emulsions encapsulating quercetin

The study used microchannel emulsification (MCE) to encapsulate quercetin in food grade oil-in-water (O/W) emulsions. A silicon microchannel plate (Model WMS 1-2) comprised of 10,300 discrete 10×104μm microslots was connected to a circular microhole with an inner diameter of 10μm. 1% (w/w) Tween 20 was used as optimized emulsifier in Milli-Q water, while 0.4mgml−1 quercetin in different oils served as a dispersed phase. The MCE was carried by injecting the dispersed phase at 2mlh−1. Successful emulsification was conducted below the critical dispersed phase flux, with a Sauter mean diameter of 29μm and relative span factor below 0.25. The O/W emulsions remained stable in terms of droplet coalescence at 4 and 25°C for 30days. The encapsulation efficiency of quercetin in the O/W emulsions was 80% at 4°C and 70% at 25°C during the evaluated storage period.

Production of stabilized quercetin aqueous suspensions by supercritical fluid extraction of emulsions

Quercetin is a flavonoid with highly promising bioactivity against a variety of diseases, due to its strong antioxidant, antiviral and antihistaminic effect, but these applications are limited by the low solubility of quercetin in gastrointestinal fluids and the correspondingly low bioavailability. The objective of this work is to produce encapsulated quercetin particles in sub-micrometric scale, in order to increase their low bioavailability. These particles were produced by extraction of organic solvent from oil in water emulsions by supercritical fluid extraction of emulsions (SFEE). Due to the rapid extraction of organic solvent by this method, the disperse organic phase becomes rapidly supersaturated, causing the precipitation of quercetin particles in sub-micrometric scale, encapsulated by the surfactant material. Two different biopolymers (Pluronic L64® poloxamers and soy bean lecithin) were used as carriers and surfactant materials. In experiments with Pluronic, needle quercetin particles were obtained after SFEE treatment, with particle sizes around 1μm and poor encapsulation efficiency. In case of soy lecithin, quercetin-loaded multivesicular liposomes were obtained, with a mean particle size around 100nm and around 70% encapsulation efficiency of quercetin, without presence of segregated quercetin crystals.

Development and evaluation of lipid nanocarriers for quercetin delivery: A comparative study of solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC), and lipid nanoemulsions (LNE)

To understand the effect of the physical state and composition of the lipid materials on the formation and performance of lipid nanocarriers, three types of carriers namely, solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and lipid nanoemulsions (LNE) were prepared and compared. Quercetin was used as a model nutraceutical compound to evaluate the potency of these nanocarriers to increase bioaccessibility. Among the developed nanocarriers, quercetin loaded and free NLC showed the smallest particle size (∼34 and 47 nm) compared to SLN (∼103 and 127 nm) and LNE (∼82 and 83 nm). Encapsulation efficiency of quercetin in these nanocarriers was >90%. Stability of these nanocarriers in simulated stomach conditions was proved by their unaffected size and size distribution after incubation in simulated gastric fluid. Maximum bioaccessibility was observed with NLC and LNE (∼60%) compared to SLN (∼35%) and free quercetin solution (∼7%). Controlled release was observed in enzyme free simulated intestinal fluid with maximum release being obtained with LNE compared to SLN and NLC. This study showed that by optimally controlling the lipid physical state and composition, it is possible to fabricate the lipid nanocarriers with desired properties.

Formation and characterization of quercetin-loaded chitosan oligosaccharide/β-lactoglobulin nanoparticle

Food grade materials including chitosan and β-lactoglobulin need to be developed for the application of nanoparticles to food science. It is hypothesized that hydrophobicity of chitosan oligosaccharide and β-lactoglobulin may be a key factor to affect the physicochemical properties of nanoparticle. The aim of this study was to investigate how substitution of chitosan oligosaccharide with linoleic acid (LA) and sub-ambient temperature treatment, which can influence hydrophobicity, affect the formation and physicochemical properties of LA-modified chitosan oligosaccharide/β-lactoglobulin (CSO-LA/β-lg) nanoparticles. CSO-LAs with different charged amounts of LA (0, 10, 20, and 30%) and β-lg mixtures at pH4.4 were sub-ambient temperature treated at 5, 10, 15, and 20°C for 30min followed by treatment with 0.5mM tripolyphosphate. Quercetin was used as a model hydrophobic bioactive compound. Spherical shape nanoparticles in the range of 170 and 350nm were successfully formed. An increase in charged amount of LA and temperature resulted in an increase in the size of CSO-LA/β-lg nanoparticles. Increasing charged amount of LA and decreasing sub-ambient temperature treatment led to an increase in the association efficiency of CSO and β-lg, respectively. Encapsulation efficiency of quercetin was enhanced with increased charged amount of LA and decreased temperature. It was concluded that charged amounts of LA and sub-ambient temperature were major key-factors affecting the size of nanoparticles and encapsulation efficiency of quercetin.

Nanoencapsulation of quercetin and resveratrol into elastic liposomes

Based on the fact that quercetin (QUE) and resveratrol (RES) induce a synergic inhibition of the adipogenesis and increase apoptosis in adipocytes, and that sodium deoxycholate (SDC) has necrotic effects, the nanoencapsulation of QUE and RES into SDC-elastic liposomes is proposed as a new approach for dissolving the subcutaneous fat. The concentration of constituents and the effect of the drug incorporation into cyclodextrin inclusion complexes on the stability of QUE/RES-loaded liposomes were studied. The best liposomal formulation reduced the use of phosphatidylcholine and cholesterol in 17.7% and 68.4%, respectively. Liposomes presented a mean diameter of 149nm with a polydispersion index of 0.3. The zeta potential of liposomes was slightly negative (−13.3mV) due to the presence of SDC in the phospholipid bilayer. Encapsulation efficiency of QUE and RES into liposomes was almost 97%. To summarize, QUE/RES-loaded elastic liposomes are stable and suitable for subcutaneous injection, thereby providing a new strategy for reducing subcutaneous fat.