Propylene Glycol Alginate Research Articles

Marine glycan-derived therapeutics in China.

A large proportion of all life on Earth lives in the ocean. Marine life includes microscopic life, plants, algae, invertebrates, fungi, and vertebrates. Due to the high salinity, high pressure, hypoxic and low temperature of the marine environment, the polysaccharides or glycans synthesized by marine life have diverse structures and unique biological activities that are not found in glycans in terrestrial life. Moreover, the glycans are the most abundant biopolymers made by the marine life. The reported activities of marine glycans include but not limit to anticoagulant, antithrombotic, antitumor, antioxidant, antiviral, and antibacterial activities. Published reports on marine glycans have increased more than threefold during the past decade. Meanwhile, several pharmaceutical companies in different countries have invested in the research and development of marine glycan-based drugs. Propylene glycol alginate sodium sulfate (PSS), the first marine glycan-based drug developed in China approved by the Chinese FDA, has been used in the treatment of cardiovascular and other diseases for more than 30 years. In this chapter, the structural characteristics, pharmacological activities and clinical applications of three Chinese FDA approved and commercially available marine glycan-based drugs (PSS, PGMS, and FPS) and five marine glycan-based drugs at different stages of clinical studies (GV971, 911, PGS, PS916, and HS203) in China will be reviewed and discussed. Understanding the marine glycan-based drugs at structure and function level would be needed to comprehend their clinical efficacy. Such knowledge will provide molecular basis for the future research and development of marine glycan-based drugs world widely.

PH-Sensitive Nanotherapeutic System Based on a Marine Sulfated Polysaccharide for Treatment of Metastatic Breast Cancer Through Combing Chemotherapy and COX-2 Inhibition

Metastasis and chemotherapy resistance are the leading causes of breast cancer mortality. Celecoxib (CXB), a selective cyclooxygenase-2 (COX-2) inhibitor, has antiangiogenetic activity and inhibitory effect on tumor metastasis, and can also enhance the sensitivity of chemotherapeutic drug doxorubicin (DOX) in breast cancer. To combine anticancer effects of DOX and CXB more efficiently, we designed a pH-sensitive nanotherapeutic system based on propylene glycol alginate sodium sulfate (PSS), a marine sulfated polysaccharide that possesses anti-platelet aggregation activity and has been used as a heparinoid drug in China. A facile one-pot nanoprecipitation method was used to prepare this nanotherapeutic system named as PDC nanoparticles, in which DOX and CXB were complexed to form hydrophobic nanocores and PPS coated these nanocores through conjugation with DOX via a highly acid-labile benzoic-imine linker. PDC nanoparticles showed distinct pH-sensitivity and significantly accelerated the release of DOX at the acidic pH mimicking the tumor microenvironment and endocytic-related organelles. Compared to single- and mixed-drug treatments, PDC nanoparticles notably inhibited the growth of mouse breast cancer 4T1 cells and reduced cell migration, invasion and adhesion abilities. In 4T1 tumor-bearing mice, PDC nanoparticles exhibited good tumor-targeting ability and markedly suppressed the tumor growth and metastasis. In summary, this nanotherapeutic system shows a great potential for clinical treatment of metastatic breast cancer by combining chemotherapy and COX-2 inhibitor.

EFEK PENAMBAHAN PROPILEN GLIKOL ALGINAT DAN ISOLAT PROTEIN KEDELAI TERHADAP MUTU FISIK DAN MUTU PENERIMAAN MI JAGUNG

Corn noodle is a potential product to be developed in non-wheat producing countries; however the texture is generally less preferred than wheat noodles. The addition of propylene glycol alginate (PGA) and soy protein isolate (SPI) to the dough was expected to decrease the hardness of corn noodles and in-crease its protein content. This study aimed to evaluate the effect of PGA (0, 0.25, 0.5, 0.75, and 1%) and SPI (0, 5, and 10%) addition on corn noodle rheology. Five parameters were analyzed i.e. cooking loss, elongation, hardness, cohesiveness and stickiness. A hedonic rating test was also performed to evaluate the corn noodle organoleptic quality. The results showed that the addition of PGA decreased the cooking loss and hardness, but increased the elongation and cohessiveness. While the addition of SPI decreased the cooking loss and cohessiveness (at PGA level 0 and 0.25%), it increased hardness and elongation (at PGA level 0%). Based on the hedonic test, corn noodle with 0.5% PGA without the addition of SPI was the most preferred formula.

Novel Bilayer Emulsions Costabilized by Zein Colloidal Particles and Propylene Glycol Alginate. 2. Influence of Environmental Stresses on Stability and Rheological Properties.

Novel bilayer emulsions co-stabilized by zein colloidal particles (ZCPs) and propylene glycol alginate (PGA) were designed to overcome some limitations of conventional emulsions or Pickering emulsions. The bilayer emulsions of various concentrations of PGA (0.01-1.50%, w/v) and different incorporation sequences of ZCPs and PGA (ZCPs/PGA and PGA/ZCPs) were fabricated using the layer by layer (LBL) electrostatic deposition technique. Influence of environmental stresses (pH 2.5-8.5; temperature 60-80 °C ; ionic strength 0-100 mM NaCl) was focused on the stability and rheological properties of the novel bilayer emulsions. In comparison to the Pickering emulsion stabilized by ZCPs alone, bilayer emulsions exhibited improved stability and unique rheological characteristics under environmental stresses. The microstructure of well-defined spheres existing a branchlike network was observed in bilayer emulsions by TEM. A comprehensive evaluation was made of the physical characteristics and stimuli-responsive behavior of bilayer emulsions. The result provided meaningful information for understanding the changing mechanism of rheology of bilayer emulsions under environmental stresses.

Preparation, characterization and stability of pea protein isolate and propylene glycol alginate soluble complexes

The application of pea protein in food products was ordinarily restricted to its poor acidic solubility and thermal stability. Propylene glycol alginate was first used to form soluble complexes with pea protein for solving these problems. In this study, the interaction between pea protein isolate (PPI) and PGA was investigated. Effects of PPI and PGA mass ratio (1:1–5:1) and pH (2–8) on the phase behavior of PPI-PGA soluble complexes were evaluated using phase diagram and zeta potential measurement. Results showed that the optimum mass ratio and pH value of the PPI-PGA binary soluble complex formed by electrostatic attraction were 3:1 and 4.0, respectively. The PPI-PGA binary soluble complex also enhanced stable and functional properties compared with native PPI. The protein solubility, emulsifying activity index and denaturation temperature were increased from 8.95 ± 1.69, 9.69 ± 0.02 and 76.69 ± 0.18 to 74.18 ± 0.81%, 82.84 ± 0.06 m2/g and 86.52 ± 2.38︒C, respectively. These improvements in the protein functionality and stability are of great practical significance to the application of pea protein in food products.

The Inhibitory Effects of PSS-Loaded Nanoparticles on the Dysfunction of Cardiac Microvascular Endothelia in Rats with Diabetic Cardiomyopathy

Propylene glycol alginate sodium sulfate-loaded nanoparticles (PSS-NP) has been shown potential to prevent the microvascular endothelial injuries caused by diabetic cardiomyopathy (DCM). In this study, we aimed to investigate the effects of PSS-NP on the dysfunction of cardiac microvascular endothelia in streptozotocin (STZ)-induced DCM rat model. Echocardiographic measurements showed a significant improvement of cardiac function in the PSS-NP-treated group. Our results revealed that the abnormalities of cardiac systolic and diastolic functions were suppressed by the treatments of prostaglandin E1 (PGE1), low molecular weight heparin (LMWH), PSS and PSS-NP. Our comparison analysis indicated that PSS-NP showed the strongest inhibitory effects on microvascular endothelial injuries. Transmission electron microscopy analysis demonstrated that PSS-NP protected the cardiac microvascular endothelium and further improved endothelium dysfunction in DCM rats. ELISA and Western blot assays further showed a high efficiency of improving cardiac microvascular endothelial dysfunction with PSS-NP. Our results demonstrated that PSS-NP increased the protein expression of phosphatidylinositol 3-kinase (PI3K)-p85 and vascular endothelial growth factor (VEGF)-A, and the phosphorylation of protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS), which were involved in the amelioration of cardiac microvascular endothelial dysfunction. These data suggest that PSS-NP may be a novel approach to the treatment the coronary microcirculation disorder diseases such as DCM.

Anti-Erosive Effect of Solutions Containing Sodium Fluoride, Stannous Chloride, and Selected Film-Forming Polymers

The aim of this study was to evaluate the anti-erosive effect of solutions containing sodium fluoride (F: 225 ppm F^–), stannous chloride (Sn: 800 ppm Sn2+), and some film-forming polymers (Gantrez: Poly [methylvinylether-alt-maleic anhydride]; PGA: propylene glycol alginate; Plasdone: poly[vinylpyrrolidone]; and CMC: carboxymethylcellulose). Solutions were tested in an erosion-remineralization cycling model, using enamel and dentin specimens (n = 10, for each substrate). Distilled water was the negative control. Cycling consisted of 120 min immersion in human saliva, 5 min in 0.3% citric acid solution, and 120 min of exposure to human saliva, 4×/day, for 5 days. Treatment with solutions (pH = 4.5) was carried out 2×/day, for 2 min. Surface loss (SL) was evaluated with optical profilometry. Zeta potential of hydroxyapatite crystals was determined after treatment with the solutions. Data were statistically analyzed (α = 0.05). For enamel, all polymers showed significantly lower SL (in µm) than the control (11.09 ± 0.94), except PGA (10.15 ± 1.25). PGA significantly improved the protective effect of F (4.24 ± 0.97 vs. 5.64 ± 1.60, respectively). None of the polymers increased the protection of F+Sn (5.13 ± 0.78). For dentin, only Gantrez (11.40 ± 0.97) significantly reduced SL when compared with the negative control (12.76 ± 0.75). No polymer was able to enhance the effect of F (6.28 ± 1.90) or F+Sn (7.21 ± 1.13). All fluoridated solutions demonstrated significantly lower SL values than the control for both substrates. Treatment of hydroxyapatite nanoparticles with all solutions resulted in more negative zeta potentials than those of the control, except Plasdone, PGA, and F+Sn+PGA, the latter two presenting the opposite effect. In conclusion, Gantrez, Plasdone, and CMC exhibited an anti-erosive effect on enamel. PGA increased the protection of F. For dentin, only Gantrez reduced erosion.

Effect of sulfobutyl ether-β-cyclodextrin and propylene glycol alginate on the solubility of clozapine

Clozapine (CLZ) is an atypical antipsychotic medication used in the treatment of schizophrenia and is poorly soluble in water (0.05 mM). In this study, we have investigated the effect of β-cyclodextrin (CD) and its derivatives on the solubility of CLZ. The solubility of the CLZ was measured to generate a phase solubility diagram, and the interaction between CLZ and sulfobutyl ether-β-cyclodextrin (SBE-β-CD) in aqueous solution was observed by 1H- and 2D rotating-frame Overhauser enhancement spectroscopy (ROESY)-NMR methods. Moreover, the synergistic effect of SBE-β-CD and water-soluble polymers, including polyvinylpyrrolidone, hydroxypropyl methylcellulose, carboxymethylcellulose sodium salt, polyvinyl alcohol, sodium alginate, and propylene glycol alginate (PGA), on the solubility of CLZ was investigated. The results show that the solubility of CLZ with 1 w/v% PGA was 7.6 mM, which was almost four times greater than that of CLZ without PGA in a 15 mM SBE-β-CD solution. In contrast, the solubility of CLZ with 1 w/v % PGA in an aqueous solution decreased by one-third relative to that of CLZ in a 15 mM SBE-β-CD solution. 2D ROESY-NMR indicated that a CLZ/SBE-β-CD/PGA ternary complex formed. It was found that the combination of PGA and SBE-β-CD enhanced the solubility of CLZ.

Performance comparison between different hydrocolloids to improve quality of pasta made from common wheat

Durum wheat is the raw material of choice for the manufacture of superior quality pasta products. However, in some parts of the world many pasta producers have to use common wheat to make pasta, which shows a deficiency with respect to quality attributes. In this respect, the functionality of different hydrocolloids in a weak common wheat flour was investigated as a comparative study with the objective to improve pasta-making potential under industrial processing conditions. Six commercial hydrocolloids, sodium alginate (AL), propylene glycol alginate (PGA), xanthan gum, carrageenan, locust bean gum or guar gum were added to wheat flour at 0.5% and 1% substitution. A rheological investigation, based on dynamic small strain tests and large deformation tests (farinograph and amylograph analyses) was performed to evaluate differences in dough structure due to interactions between flour components and hydrocolloids, and related to cooking properties of pasta. All hydrocolloids promoted an increase in elastic interactions in the dough. The strongest doughs were obtained by addition of alginates. Only cooked pasta supplemented with AL, PGA and XG showed an increase in firmness compared with the reference (PGA > AL > XG). The product enriched with 0.5% PGA or 1% AL gave the highest overall acceptability and sensory scores. On the contrary, xanthan gum, carrageenan, locust bean gum or guar gum performed relatively poorly in flour. On the basis of these results alginates were the most effective improvers of pasta quality among different hydrocolloids.

Novel Bilayer Emulsions Costabilized by Zein Colloidal Particles and Propylene Glycol Alginate, Part 1: Fabrication and Characterization.

In this study, both zein colloidal particles (ZCPs) and propylene glycol alginate (PGA) were simultaneously applied to prepare novel bilayer emulsions using the method of layer-by-layer (LBL) electrostatic deposition. The effects of different concentrations of PGA as well as incorporating sequences of ZCPs and PGA on physical stability and microstructure of bilayer emulsions were investigated. Furthermore, optical microscopy as well as confocal laser scanning microscopy (CLSM) showed that the oil droplets presented uniform spheres and a compact network appeared in bilayer emulsion. Compared to the Pickering emulsion stabilized by ZCPs alone, novel bilayer emulsions exhibited simultaneous and long-term stability against creaming, coalescence, and Ostwald ripening due to the unique interface framework of a particle-polysaccharide hierarchical structure. Novel bilayer emulsions synergistically stabilized by colloidal particles and biopolymers were designed by using interfacial engineering, and a promising pathway was found to produce stable bilayer emulsions for the delivery of bioactive compounds.

The efficacy of propylene glycol alginate (PGA), a food additive, in controlling Haemaphysalis longicornis ticks

Ticks and tick-borne pathogens threaten the health of both domestic animals and humans, and are associated with a high economic burden in many countries. Tick control can be achieved with chemical acaricides, but issues remain regarding their safety as well as emerging tick resistance. Propylene glycol alginate (PGA) is a food additive commonly used in China. It has been used to kill whiteflies in agriculture as an environmentally friendly insecticide. The aims of this study were to (i) explore the efficacy of PGA to kill Haemaphysalis longicornis ticks and (ii) assess the potential to develop a new tick control acaricide containing PGA and a reduced amount of synthetic pyrethroid. Beta-cypermethrin was chosen as the reference pyrethroid in this study. PGA, beta-cypermethrin and mixes (PGA and beta-cypermethrin formulated in proportions of A = 2:1, B = 1:1, and C = 1:2) were compared for efficacy to kill larval and adult H. longicornis ticks. Overall, we found no statistically significant differences in the killing efficacy of PGA as compared to beta-cypermethrin across examined time-points post-tick exposure. At 24 h post-tick exposure, similar killing efficacy for H. longicornis larvae was recorded for beta-cypermethrin alone, PGA alone, and mixed formulations B and C. Mixed formulation C had the strongest killing effect when compared to PGA alone or mixed formulation B. Similar outcomes were observed in experiments with adult H. longicornis ticks. Based on these findings, we propose that PGA can be useful as a tick control acaricide, either as a single active ingredient or formulated together with a pyrethroid.

Composite zein - propylene glycol alginate particles prepared using solvent evaporation: Characterization and application as Pickering emulsion stabilizers

There is great interest in identifying biopolymer-based particles to stabilize Pickering emulsions. Pure zein particles are easy to fabricate but are unsuitable for this purpose because of their high hydrophobicity. In this study, composite zein - propylene glycol alginate particles (ZPGAPs) were prepared using a solvent evaporation method. The potential of using these particles to stabilize oil-in-water emulsions through a Pickering mechanism was also studied. ZPGAPs prepared at a zein-to-PGA mass ratio of 10:1 had considerably smaller particle diameters (346 nm) than those prepared using pure zein (1400 nm) as determined by light scattering and scanning electron microscopy (SEM). The interface wettability of ZPGAPs mainly depended on the zein-to-PGA mass ratio. The three-phase contact angle (θ) of pure zein particles was around 68.1° whereas that of ZPGAPs was around 90°, suggesting that the composite particles had suitable wettability characteristics for stabilizing Pickering emulsions. Confocal laser scanning microscope (CLSM) images showed that ZPGAPs formed a densely packed layer around the surfaces of the oil droplets, further highlighting the potential of the composite particles as emulsion stabilizers. The elastic modulus (G′) was higher than the loss modulus (G″) in all the Pickering emulsions, which was indicative of the formation of an elastic gel-like structure. The rheological properties of the Pickering emulsions could be modulated by altering the composite particle concentration, droplet concentration, ionic strength, pH, and temperature. These results suggest that the ZPGAPs developed in this work may be a promising stabilizer of Pickering emulsions and may extend the application of zein in food products.

Properties of Ternary Biopolymer Nanocomplexes of Zein, Sodium Caseinate, and Propylene Glycol Alginate and Their Functions of Stabilizing High Internal Phase Pickering Emulsions

A pH-cycle method based on preparing an alkaline solution of zein followed by neutralization with an acid can be used to prepare zein nanoparticles. In the present work, partial alkaline hydrolysis of propylene glycol alginate (PGA) to a lower pH was studied to prepare binary zein-PGA nanocomplexes and ternary complexes with additional sodium caseinate (NaCas). 0.5% or more PGA was sufficient to reduce the pH to 7.5 or lower, eliminating the need for titration, and resulted in simultaneous nanocomplex formation. The addition of NaCas into alkaline zein-PGA solution resulted in smaller complexes with all biopolymers, whereas adsorption on binary zein-PGA complexes was observed when NaCas was added into the neutral zein-PGA dispersions. The formation of nanocomplexes involved with hydrophobic and electrostatic attractions and hydrogen bonds and was further affected by the amount of NaCas. The ternary nanocomplexes with equal masses of zein and NaCas had an excellent capacity to prepare gel-like Pickering emulsions with as much as 80% v/v oil with characteristics suitable for texture modification and delivery systems of bioactive compounds in food and consumer products. Therefore, PGA can be used to possibly scale-up the pH-cycle method to produce zein-based nanoparticles with unique functional properties.

Development of protein-polysaccharide-surfactant ternary complex particles as delivery vehicles for curcumin

In this study, protein/polysaccharide/surfactant complexes were prepared by anti-solvent co-precipitation using zein, propylene glycol alginate (PGA), and either rhamnolipid or lecithin. The potential of using these ternary complexes as delivery systems for increasing the stability and bioaccessibility of curcumin (Cur) was investigated. Curcumin-loaded zein, zein-PGA, zein-PGA-rhamnolipid, and zein-PGA-lecithin complexes are abbreviated as Z-Cur, Z-P-Cur, Z-P-R-Cur and Z-P-L-Cur, respectively. The presence of polysaccharides and surfactants in the complexes increased the encapsulation efficiency of the curcumin compared to zein nanoparticles alone: Z-Cur (21%); Z-P-Cur (67%); Z-P-R-Cur (92%); and, Z-P-L-Cur (94%). X-ray diffraction indicated that curcumin was present in an amorphous state inside the complexes. Fourier transform infrared and fluorescence spectroscopy indicated that electrostatic interactions, hydrogen bonding, and hydrophobic effects were the main forces involved in complex formation. Light scattering and electrophoresis measurements showed that the particle size and charge of the complexes depended on their composition. The presence of the surfactants in the complexes significantly improved the photo-stability and bioaccessibility of curcumin. Our results suggest that the ternary complexes developed in this study might be a promising means of encapsulating, protecting, and delivering hydrophobic nutraceuticals for applications in foods, supplements, and pharmaceuticals.

Development of Rice Spaghetti Using Propylene Glycol Alginate and Soy Flour by Twin- Screw Extrusion

Development of Rice Spaghetti Using Propylene Glycol Alginate and Soy Flour by Twin- Screw Extrusion

Effects of temperature, relative humidity, and protective netting on Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae) infestation, fungal growth, and product quality of dry cured hams

Since methyl bromide is an ozone depleting substance, there is a need to find effective alternative methods to control mite infestations on dry cured hams. Therefore, the objective of this study was to determine the most effective relative humidity and/or temperature combination to minimize mite reproduction and mold growth on dry cured hams in untreated and food-grade ingredient infused nets. Food grade coating formulations of 1) xanthan gum and propylene glycol, and 2) carrageenan, propylene glycol alginate, and propylene glycol nets were infused into nets. Dry cured ham cubes and slices were wrapped with untreated and treated nets, inoculated with 20 large mixed-sex mites per cube or 50 large mixed-sex mites per slice, and then stored for 14 d at each temperature (24, 28, and 32 °C) and RH (55, 65, 75, and 85%) combination in an environmental chamber. Tyrophagus putrescentiae on ham slices in untreated nets were reduced from the initial inoculum level of 50 mites per ham slice when exposed to 85% r.h. at 24, 28, and 32 °C. Nets infused with xanthan gum and propylene glycol or carrageenan, propylene glycol alginate, and propylene glycol, completely inhibited mite reproduction at 85% r.h. In addition, the nets infused with carrageenan, propylene glycol alginate, and propylene glycol, controlled mite reproduction below the initial inoculum level on ham cubes and ham slices at all temperatures and relative humidities that were evaluated. Six to eight trained panelists rated the amount of mold on the ham slice surfaces on a 0–100% scale and both treated nets evaluated were effective at preventing mold growth on the ham slices.

The mechanisms of sulfated polysaccharide drug of propylene glycol alginate sodium sulfate (PSS) on bleeding side effect

Propylene glycol alginate sodium sulfate (PSS), a sulfated polysaccharide derivative, has been used as a heparinoid drug to prevent and treat hyperlipidemia and ischemic cardio-cerebrovascular diseases in China for 30 years. But its bleeding risk should not be overlooked. Here we clarified the reasons and mechanism leading to bleeding side effect of PSS. It was found that PSS fractions with low mannuronic acid (M)/guluronic acid (G) ratio and high molecular weight (Mw) can excessively extend activated partial thromboplastin time (APTT) and thrombin time (TT), over-inhibit the thrombin (FIIa) activity mediated by anti-thrombin III (ATIII) to induce bleeding risk. In addition, the fraction of low M/G ratio can suppress platelet aggregation mediated by adenosine diphosphate (ADP) and induce platelet reduction by improving platelet antibody (PA)-IgA/G in serum and by inhibiting or damaging the bone marrow hematopoietic function. And the fraction of high Mw can restrain the reticulated platelet (RP) production, then reduce mean platelet volume (MPV) and platelet-large cell counts or ratio, and finally decrease platelet amount by inhibiting or damaging the bone marrow hematopoietic function. In brief, PSS fractions with low M/G ratio and high Mw were the main reasons to bring about bleeding by excessively suppressing coagulant factors activities and weakening platelet function. Our results suggested that it is very necessary to control the M/G ratio and the range of Mw of PSS to guarantee its safety and effectiveness in clinical.

Incorporating fermented by-products of Lactobacillus diolivorans in food grade coatings designed for inhibition of Tyrophagus putrescentiae on dry-cured hams

Distillate solutions that were derived from concentrated ferment of Lactobacillus diolivorans were incorporated into either a carrageenan (CG) and propylene glycol alginate (PGA) gum blend or into a CG, PGA, and xanthan gum (XG) blend. Fermented distillate was produced in a model system to mimic fermentation in food grade coatings to produce 1, 3 propanediol, acetic acid, and lactic acid. Distillate treatments were compared against a 10% propylene glycol treatment, a gum only control, and negative control on 2.5 × 2.5 × 2.5 cm cubes (n = 50) that were dipped into solutions prior to conducting mite bioassays. Coated and control ham cubes were inoculated with 20 adult T. putrescentiae (Schrank), and incubated for 2 and 3 weeks. The distilled treatments with CG + PGA + XG had a 20 fold or greater reduction (P < 0.05) in mite populations than all other treatments with the exception of the 10% PG coated treatments. In addition, there were no differences between treatments with respect to sensory texture, flavor, and moistness. This indicates that fermentation within food grade coatings could be evaluated on the surface of dry-cured ham to determine if the success in a model system could be reproduced in practice.

Formation and characterization of zein-propylene glycol alginate-surfactant ternary complexes: Effect of surfactant type

In this study, zein, propylene glycol alginate (PGA) and surfactant ternary complexes were fabricated by antisolvent co-precipitation method. Two types of surfactants (rhamnolipid and lecithin) were applied to generate zein-PGA-rhamnolipid (Z-P-R) and zein-PGA-lecithin (Z-P-L) ternary complexes, respectively. Results showed that the surfactant types significantly affected the properties of ternary complexes. The formation of ternary complexes was mainly due to the non-covalent interactions such as hydrogen bonding, electrostatic interaction and hydrophobic interactions among zein, PGA and surfactants. Moreover, the thermal stability of ternary complexes was enhanced with increasing the levels of both surfactants. Notably, ternary complex dispersions exhibited better stability against pH from 2 to 8. Furthermore, a compact network structure was observed in Z-P-R ternary complex, while Z-P-L ternary complex remained the spherical structure. These findings would provide new insights into the development of novel delivery system and expand the options, when zein-based complexes were utilized under different environment conditions.

Development of an enteric nanoparticle of marine sulfated polysaccharide propylene glycol alginate sodium sulfate for oral administration: formulation design, pharmacokinetics and efficacy.

Propylene glycol alginate sodium sulfate (PSS) is poorly absorbed by oral administration due to its large molecular weight and slightly degradability in stomach acidic environment. Here, a novel enteric-coated nano formulation of PSS (enteric PSS-NP) was prepared to improve its bioavailability and efficacy. The enteric PSS-NP was prepared by double (W1 /O/W2 ) emulsion and solvent evaporation method. The drug release characteristics in vitro were studied in artificial gastrointestinal fluid. And the pharmacokinetics and efficacy of enteric PSS-NP were separately investigated in normal rats and type 2 diabetic db/db mice. The enteric PSS-NP were in spherical shape and exhibited negative zeta potential. The releasing characteristics of enteric PSS-NP in vitro showed that it possessed a strong pH-sensitive release character. Single-dose (50 mg/kg) oral pharmacokinetic study in rat plasma showed that enteric PSS-NP could improve the relative bioavailability significantly compared with PSS solution. Furthermore, the efficacy of enteric PSS-NP in vivo was better than that of PSS solution at equivalent doses. The study showed that enteric-coated formulation of PSS had the intestinal-targeted absorption and improved pharmacodynamics, which indicated that enteric PSS-NP could be developed into a new formulation product in the future.