This study reports the synthesis of oleic acid sterol ester with liquid crystalline properties and its enhanced stability and UV-blocking performance through microencapsulation.Oleic acid sterol ester was synthesized ...This study reports the synthesis of oleic acid sterol ester with liquid crystalline properties and its enhanced stability and UV-blocking performance through microencapsulation.Oleic acid sterol ester was synthesized via the esterification of phytosterol and oleic acid,whose structure was characterized using Fourier-transform infrared spectroscopy(FTIR)and mass spectrometry(MS).Its liquid crystalline behavior was confirmed via the polarized optical microscopy(POM),thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),wide-angle X-ray scattering(WAXS),and small-angle X-ray scattering(SAXS).UV absorption tests were conducted to assess the UV-blocking performance of the oleic acid sterol ester liquid crystals.To improve the stability of its liquid crystalline structure,the oleic acid sterol ester was encapsulated into microcapsules through the emulsion polymerization.SPF measurements were performed on the sunscreen formulations containing liquid crystal microcapsules.The oleic acid sterol ester displayed cholesteric liquid crystalline behavior and strong UVA absorption,which indicates its suitability as a natural UV absorber.Microencapsulation further enhanced its stability and UV-blocking properties.SPF testing showed that the formulations with microcapsules achieved an SPF value of 7.01,which surpasses the nano titanium dioxide(SPF=6.23)and significantly outperform the unencapsulated liquid crystal formulations(SPF=2.65).This study highlights the potential of microencapsulated oleic acid sterol ester as a novel UV absorber in the sunscreen formulations,offers the enhanced stability and effective UV protection,and showcases its application potential in the innovative cosmetic products.展开更多
Vitamin A palmitate (VAP) contains retinol and palmitic acid which is easily absorbed by body and widely used in skin care products. But, it is a hydrophobic and oxidation sensitive molecule which undergoes rapid degr...Vitamin A palmitate (VAP) contains retinol and palmitic acid which is easily absorbed by body and widely used in skin care products. But, it is a hydrophobic and oxidation sensitive molecule which undergoes rapid degradation especially in an aqueous environment. The purpose of this study was to prepare microcapsules of VAP using combination maltodextrin and modified starches. Emulsion of VAP was prepared using cremophore RH 40 with Tween 80 in a homogenizer and formed emulsion was spray-dried. The spray process was optimized using a central composite design for two variables to obtain microcapsules with desirable characteristics. Microcapsules containing 30% of VAP were produced using different concentration of wall materials. The prepared microcapsules were evaluated for their physical, morphological, in-vitro drug release and SEM study. The results showed that obtained microcapsules are nearly spherical in shape with a particle size ranged from 1 to 12 μm. The drug content and encapsulation efficiency (53% - 63%) of different batches were found within acceptable range. These stabilized drug loaded microcapsules were incorporated into silicone cream based formulation for convenient topical application and evaluated for its physicochemical parameters. The drug release study showed 80.18% to 83.43% of drug release from VAP microcapsules while topical formulations prepared by VAP microcapsules showed 67.09% to 71.45% drug release at the end of 24 hrs. The formulations were kept for 3 months stability study as per ICH guidelines and found to be stable.展开更多
Indonesia is the largest palm oil producer in the world. The content of β-carotene in palm oil, which can act as pro-vitamin A, is relatively high, so it has great potential for overcoming cases of vitamin A deficien...Indonesia is the largest palm oil producer in the world. The content of β-carotene in palm oil, which can act as pro-vitamin A, is relatively high, so it has great potential for overcoming cases of vitamin A deficiency. By microencapsulation process of palm oil, β-carotene content in palm oil will be more stable and have a longer shelf life. There are three methods of microencapsulation used in this study, namely coacervation, thin-layer drying, and SiO2 absorption technique, which theoretically are suitable for encapsulating β-carotene in palm oil. The aim of this research is to compare and find the most suitable method of microencapsulation process of palm oil to obtain the highest β-carotene content and retention. Results show that those three methods are significantly different in affecting water absorption, solubility in water, yield, microencapsulation efficiency, β-carotene content, and retention of microencapsulated palm oil. The microencapsulated palm oil made from thin layer drying method has the highest β-carotene content at 200.16 μg/g and β-carotene retention of 68.89%. It also has low water absorption and high water solubility, so it can be applied as a powder premix in food as vitamin A supplement.展开更多
We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a ...We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a supercritical CO2 solution.? A suspension of CaCO3 in CO2 and dissolved poly(HDFDA) were mixed in supercritical CO2.? After the system pressure was slowly decreased to atmospheric pressure, the microcapsules were obtained.? Coacervation was achieved by the precipitation of poly(HDFDA) during the decrease in the pressure of CO2;the solubility of poly(HDFDA) in CO2 decreased with the pressure.? The structure and morphology of the microparticles were investigated by using a scanning electron microscope (SEM) and an electron probe microanalyzer (EPMA) equipped with a wavelength dispersive X-ray spectroscope (WDX).展开更多
Banana passion fruit (P. tripartita var. Mollissima) is one of the most promising tropical fruits giving its antioxidant activity (AOA) to replace synthetic additives. Despite this property, there are no studies about...Banana passion fruit (P. tripartita var. Mollissima) is one of the most promising tropical fruits giving its antioxidant activity (AOA) to replace synthetic additives. Despite this property, there are no studies about the metabolites responsible for its biological function or proposals for the application of technologies, such as microencapsulation by spray drying, to improve its properties and ease its incorporation in several food matrices. The aim of this study is to microencapsulate the pulp of banana passion fruit with several mixtures of encapsulants and identify which one of these mixtures is better to preserve its AOA. The antioxidant activity values for the banana passion fruit pulp were as follows: DPPH: 6630.2 ± 91 μMtrolox/100g;ABTS: 18764.3 ± 270.4 μMtrolox/100g;FRAP: 1703.6± 938.2 mgAA/100g, ORAC: 8105.4 ± 424.2 μmol TEAC/100g of sample;Total phenols: 8862.2 ± 451.4 gallic ac. mg/100g. The concentrations of the bioactive compounds expressed in mg of gallic acid per 100 g of the pulp on a dry base were 13.9 ± 0.004;5.9 ± 0.001 and 126.3 ± 0.004 for caffeic, p-coumaric and ferulic acids, respectively. The best shelf-life followed by ABTS in eight assays was between 28.8 and 31.5 weeks using maltodextrin and modified starch, MD:MS (1/4:3/4) and MD:MS (0:1), respectively. In conclusion, ABTS is the best method to measure the AOA in banana passion fruit because it correlated with the phenolic compounds better than DPPH and FRAP methods. Additionally, two options were found to protect the AOA and to extent the shelf-life of the passion fruit by spray-drying, with mixtures of encapsulants widely used in the food industry.展开更多
Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated...Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated by alginate(ALG)and coated with chitooligosaccharide(COS).A response surface methodology was used to optimize the formulation,and a simulated gastrointestinal(GI)digestion(SGID)system to evaluate the controlled release of microencapsulated Ig Y.The microcapsule formulation was optimized as an ALG concentration of 1.56%(15.6 g/L),COS level of 0.61%(6.1 g/L),and Ig Y/ALG ratio of 62.44%(mass ratio).The microcapsules prepared following this formulation had an encapsulation efficiency of 65.19%,a loading capacity of 33.75%,and an average particle size of 588.75μm.Under this optimum formulation,the coating of COS provided a less porous and more continuous microstructure by filling the cracks on the surface,and thus the GI release rate of encapsulated Ig Y was significantly reduced.The release of encapsulated Ig Y during simulated gastric and intestinal digestion well fitted the zero-order and first-order kinetics functions,respectively.The microcapsule also allowed the Ig Y to retain 84.37%immune-activity after 4 h simulated GI digestion,significantly higher than that for unprotected Ig Y(5.33%).This approach could provide an efficient way to preserve Ig Y and improve its performance in the GI tract.展开更多
In this study, linoleic acid (LA) was encapsulated in the presence or absence of quercetin into a dual polymer system of whey protein and kappa-carrageenan using power ultrasound. Atomic Force Microscopy (AFM) and Flo...In this study, linoleic acid (LA) was encapsulated in the presence or absence of quercetin into a dual polymer system of whey protein and kappa-carrageenan using power ultrasound. Atomic Force Microscopy (AFM) and FlowCam imaging technology were used for imaging and size determination of nano-and micro-capsules. Differential scanning calorimeter (DSC) was used to determine the glass transition temperature (Tg) of the freeze-dried nanocapsules. In order to examine the effect of water activity (aw) on the release profile of the encapsulated LA, the nanocapsules were equilibrated over saturated salt solution conditions corresponding to the range of aw between 0.333 and 0.769 in evacuated desiccators at room temperature. Gravimetric measurements of the steady state linoleic acid (LA) contents were conducted. The anti-oxidant activity of quercetin and the stability of encapsulated LA toward long term and thermally induced rancidity was investigated. The capsules were in the nanosize regime and 83% of the LA was effectively encapsulated. Furthermore, at aw of 0.764, the highest percentage of LA (74%) was released from the expelling nanocapsules. Quercetin was found to exhibit protective antioxidant effect against time-dependent oxidation and thermally induced rancidity of LA. Water activity values of 0.662 and 0.764 provided ideal humidity and pressure conditions for sustained release of nanoencapsulated LA at room temperature.展开更多
A dual emission sensing film has been prepared for colorimetric temperature sensing using CsPbBr_(3)perovskite nanocrystals(CsPbBr_(3)NCs)and manganese doped potassium fluorosilicate(K_(2)SiF_(6):Mn^(4+),KSF)encapsula...A dual emission sensing film has been prepared for colorimetric temperature sensing using CsPbBr_(3)perovskite nanocrystals(CsPbBr_(3)NCs)and manganese doped potassium fluorosilicate(K_(2)SiF_(6):Mn^(4+),KSF)encapsulated in polystyrene by a microencapsulation strategy.The CsPbBr_(3)-KSF-PS film shows good temperature sensing response from 30℃to 70℃,with a relative temperature sensitivity(Sr)up to 10.31%℃^(−1) at 45℃.Meanwhile,the film maintains more than 95%intensity after 6 heating-cooling cycles and keeps its fluorescence characteristics after 3 months.The film can be used to monitor temperature change by naked eye under a UV lamp.In particular,the temperature discoloration point of the sensing film can be controlled by the ratio change of CsPbBr_(3):KSF to expand its applications.The study of the CsPbBr_(3)-KSF-PS sensing mechanism in this work is helpful to provide effective strategies for the design of reliable,high sensitivity and stable temperature sensing system using CsPbBr_(3)NCs.展开更多
L-ascorbic acid is a water soluble vitamin (vitamin C) widely used as an additive in foods and cosmetics. It has high instability against certain environmental factors;the main cause of its deterioration is oxidation....L-ascorbic acid is a water soluble vitamin (vitamin C) widely used as an additive in foods and cosmetics. It has high instability against certain environmental factors;the main cause of its deterioration is oxidation. Microencapsulation is an effective protection technique of L-ascorbic acid from its degradation reactions. This work is focused on the encapsulation of L-ascorbic acid by spray drying technique using sodium alginate as wall material. The microcapsules morphology was observed by scanning electron microscopy (SEM) and the encapsulation efficiency was determined by spectrophotometric analysis. Results showed that encapsulation efficiency was of 93.48% and after 30 days was of 92.55%;differences were not significant, so that the stability of L-ascorbic acid was not affected. Encapsulation yields obtained were low, at around 30%, but the microcapsules morphology obtained is spherical.展开更多
Enzymes have been used in detergents over the years. They can improve the detergent’s efficiency due to their activities against hard stains. Nevertheless, enzymes cannot maintain their properties indefinitely, since...Enzymes have been used in detergents over the years. They can improve the detergent’s efficiency due to their activities against hard stains. Nevertheless, enzymes cannot maintain their properties indefinitely, since they are exposed to stress factors, like temperature, pH, mechanical processes and others. Consequently, enzymes lose their structure and they are not functional. For this reason, microencapsulating these proteins is a feasible solution to improve their use in industrial processes and commercial products. Spray drying technology has been selected because a lot of scientific literature proved its useful application in a variety of industries. In particular, savinase and lipase are the two encapsulated enzymes in this work. Savinase attacks proteins and lipase removes fats, so they are suitable enzymes for detergent industry. Arabic gum has been used as wall material. Morphology, size and activity of the obtained microcapsules have been analyzed in order to find the best conditions to produce them. In conclusion, useful microcapsules of lipase and savinase can be obtained with the mentioned technology.展开更多
[Objective] The aim of this study was to explore the microencapsulation of peony oil. [Method] Using [5-cyclodextrin, Arabic gum and soy protein as the wall materials and by the preparation technology of peony oil thr...[Objective] The aim of this study was to explore the microencapsulation of peony oil. [Method] Using [5-cyclodextrin, Arabic gum and soy protein as the wall materials and by the preparation technology of peony oil through spray drying, we conducted single factor experiments and orthogonal experiment analysis of the tech- nical parameters of peony oil microencapsulation. [Result] The optimal parameters of peony oil microcapsule preparation were acquired. The ratio of three wall materials （~5-cyclodextrin, Arabic gum, and soy protein） is 3：1：2, the solid content is 35%, the ratio of core-wall material is 3：1, emulsifier dosage is 0.2%, and the embedding rate of peony oil reaches 92%. [Conclusion] This technology produced the highest em- bedding rate and it laid the foundation for further development of peony oil.展开更多
Acrocomia aculeata (Jacq.) Lodd. shows possibilities for pharmaceutical, food and chemical use. However, its application is limited due to the loss of its bioactive components. Microencapsulation may be an alternative...Acrocomia aculeata (Jacq.) Lodd. shows possibilities for pharmaceutical, food and chemical use. However, its application is limited due to the loss of its bioactive components. Microencapsulation may be an alternative to reduce such problems. A step-by-step optimization approach was used in this work for preservation of bioactive compounds. The applied technique to microencapsulate the Acrocomia aculeata oil was efficient, producing between 64% and 99% of microcapsules and 59% to 97% of encapsulated oil. In the experimental design, temperature was the parameter that significantly influenced the carotenoids of microcapsules. Complex coacervation helped to preserve carotenoids and the antioxidant activity, and an interaction between the temperature and the content was observed for such preservation.展开更多
With the microencapsulation technique for immunoisolation of transplanted tissues, a study on pituitary transplantation was performed in our lab. Mixed fetal pituitary hypothalamic nigral cells were microencapsulate...With the microencapsulation technique for immunoisolation of transplanted tissues, a study on pituitary transplantation was performed in our lab. Mixed fetal pituitary hypothalamic nigral cells were microencapsulated and cultured to investigate the secretion of growth hormone (GH), prolactin(PRL) and PRL releasing function stimulated by thyrotropin releasing hormone (TRH) in the medium. Rabbits were immunized with the encapsulated cells for 50 days. The results revealed that: ①GH, PRL could be secreted into medium through the capsules; ②PRL concentration augmented when TRH was added to the medium; ③No antibody against the fetal brain tissue could be detected in rabbit serum. These indicated that the material and the procedure of microencapsulation did not disturb the viability and function of encapsulated cells; the membrane of the microencapsulation was permeable to the pituitary hormones and hypothalamic factors, and had the function of immunoisolation.展开更多
Aiming to identify the validity of fabricating microencapsulated phase change material(PCM) with polymethylmethacrylate(PMMA) by ultraviolet curing emulsion polymerization method using iron(III) chloride as photoiniti...Aiming to identify the validity of fabricating microencapsulated phase change material(PCM) with polymethylmethacrylate(PMMA) by ultraviolet curing emulsion polymerization method using iron(III) chloride as photoinitiator,SA/PMMA microcapsules were prepared and various techniques were employed to determine the ignition mechanism,structural characteristics and thermal properties of the composite.The results shown that the microcapsules containing SA with maximum percentage of 52.20 wt% formed by radical mechanism and only physical interactions existed in the components both in the prepared process and subsequent use.The phase change temperatures and latent heats of the microencapsulated SA were measured as 55.3 °C and 102.1 J·g^(-1) for melting,and 48.8 °C and 102.8 J·g^(-1) for freezing,respectively.Thermal gravimetric analysis revealed that SA/PMMA has good thermal durability in working temperature range.The results of accelerated thermal cycling test are all shown that the SA/PMMA have excellent thermal reliability and chemical stability although they were subjected 1000 melting/freezing cycles.In summary,the comparable thermal storage ability and good thermal reliability facilitated SA/PMMA to be considered as a viable candidate for thermal energy storage.The successful fabrication of SA/PMMA capsules indicates that ferric chloride is a prominent candidate for synthesizing PMMA containing PCM composite.展开更多
Olfactory bulb tissue transplantation inhibits P2X2/3 receptor-mediated neuropathic pain. However, the olfactory bulb has a complex cellular composition, and the mechanism underlying the action of purified transplante...Olfactory bulb tissue transplantation inhibits P2X2/3 receptor-mediated neuropathic pain. However, the olfactory bulb has a complex cellular composition, and the mechanism underlying the action of purified transplanted olfactory ensheathing cells（OECs） remains unclear. In the present study, we microencapsulated OECs in alginic acid, and transplanted free and microencapsulated OECs into the region surrounding the injured sciatic nerve in rat models of chronic constriction injury. We assessed mechanical nociception in the rat models 7 and 14 days after surgery by measuring paw withdrawal threshold, and examined P2X2/3 receptor expression in L4–5 dorsal root ganglia using immunohistochemistry. Rats that received free and microencapsulated OEC transplants showed greater withdrawal thresholds than untreated model rats, and weaker P2X2/3 receptor immunoreactivity in dorsal root ganglia. At 14 days, paw withdrawal threshold was much higher in the microencapsulated OEC-treated animals. Our results confirm that microencapsulated OEC transplantation suppresses P2X2/3 receptor expression in L4–5 dorsal root ganglia in rat models of neuropathic pain and reduces allodynia, and also suggest that transplantation of microencapsulated OECs is more effective than transplantation of free OECs for the treatment of neuropathic pain.展开更多
文摘This study reports the synthesis of oleic acid sterol ester with liquid crystalline properties and its enhanced stability and UV-blocking performance through microencapsulation.Oleic acid sterol ester was synthesized via the esterification of phytosterol and oleic acid,whose structure was characterized using Fourier-transform infrared spectroscopy(FTIR)and mass spectrometry(MS).Its liquid crystalline behavior was confirmed via the polarized optical microscopy(POM),thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),wide-angle X-ray scattering(WAXS),and small-angle X-ray scattering(SAXS).UV absorption tests were conducted to assess the UV-blocking performance of the oleic acid sterol ester liquid crystals.To improve the stability of its liquid crystalline structure,the oleic acid sterol ester was encapsulated into microcapsules through the emulsion polymerization.SPF measurements were performed on the sunscreen formulations containing liquid crystal microcapsules.The oleic acid sterol ester displayed cholesteric liquid crystalline behavior and strong UVA absorption,which indicates its suitability as a natural UV absorber.Microencapsulation further enhanced its stability and UV-blocking properties.SPF testing showed that the formulations with microcapsules achieved an SPF value of 7.01,which surpasses the nano titanium dioxide(SPF=6.23)and significantly outperform the unencapsulated liquid crystal formulations(SPF=2.65).This study highlights the potential of microencapsulated oleic acid sterol ester as a novel UV absorber in the sunscreen formulations,offers the enhanced stability and effective UV protection,and showcases its application potential in the innovative cosmetic products.
文摘Vitamin A palmitate (VAP) contains retinol and palmitic acid which is easily absorbed by body and widely used in skin care products. But, it is a hydrophobic and oxidation sensitive molecule which undergoes rapid degradation especially in an aqueous environment. The purpose of this study was to prepare microcapsules of VAP using combination maltodextrin and modified starches. Emulsion of VAP was prepared using cremophore RH 40 with Tween 80 in a homogenizer and formed emulsion was spray-dried. The spray process was optimized using a central composite design for two variables to obtain microcapsules with desirable characteristics. Microcapsules containing 30% of VAP were produced using different concentration of wall materials. The prepared microcapsules were evaluated for their physical, morphological, in-vitro drug release and SEM study. The results showed that obtained microcapsules are nearly spherical in shape with a particle size ranged from 1 to 12 μm. The drug content and encapsulation efficiency (53% - 63%) of different batches were found within acceptable range. These stabilized drug loaded microcapsules were incorporated into silicone cream based formulation for convenient topical application and evaluated for its physicochemical parameters. The drug release study showed 80.18% to 83.43% of drug release from VAP microcapsules while topical formulations prepared by VAP microcapsules showed 67.09% to 71.45% drug release at the end of 24 hrs. The formulations were kept for 3 months stability study as per ICH guidelines and found to be stable.
文摘Indonesia is the largest palm oil producer in the world. The content of β-carotene in palm oil, which can act as pro-vitamin A, is relatively high, so it has great potential for overcoming cases of vitamin A deficiency. By microencapsulation process of palm oil, β-carotene content in palm oil will be more stable and have a longer shelf life. There are three methods of microencapsulation used in this study, namely coacervation, thin-layer drying, and SiO2 absorption technique, which theoretically are suitable for encapsulating β-carotene in palm oil. The aim of this research is to compare and find the most suitable method of microencapsulation process of palm oil to obtain the highest β-carotene content and retention. Results show that those three methods are significantly different in affecting water absorption, solubility in water, yield, microencapsulation efficiency, β-carotene content, and retention of microencapsulated palm oil. The microencapsulated palm oil made from thin layer drying method has the highest β-carotene content at 200.16 μg/g and β-carotene retention of 68.89%. It also has low water absorption and high water solubility, so it can be applied as a powder premix in food as vitamin A supplement.
文摘We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a supercritical CO2 solution.? A suspension of CaCO3 in CO2 and dissolved poly(HDFDA) were mixed in supercritical CO2.? After the system pressure was slowly decreased to atmospheric pressure, the microcapsules were obtained.? Coacervation was achieved by the precipitation of poly(HDFDA) during the decrease in the pressure of CO2;the solubility of poly(HDFDA) in CO2 decreased with the pressure.? The structure and morphology of the microparticles were investigated by using a scanning electron microscope (SEM) and an electron probe microanalyzer (EPMA) equipped with a wavelength dispersive X-ray spectroscope (WDX).
文摘Banana passion fruit (P. tripartita var. Mollissima) is one of the most promising tropical fruits giving its antioxidant activity (AOA) to replace synthetic additives. Despite this property, there are no studies about the metabolites responsible for its biological function or proposals for the application of technologies, such as microencapsulation by spray drying, to improve its properties and ease its incorporation in several food matrices. The aim of this study is to microencapsulate the pulp of banana passion fruit with several mixtures of encapsulants and identify which one of these mixtures is better to preserve its AOA. The antioxidant activity values for the banana passion fruit pulp were as follows: DPPH: 6630.2 ± 91 μMtrolox/100g;ABTS: 18764.3 ± 270.4 μMtrolox/100g;FRAP: 1703.6± 938.2 mgAA/100g, ORAC: 8105.4 ± 424.2 μmol TEAC/100g of sample;Total phenols: 8862.2 ± 451.4 gallic ac. mg/100g. The concentrations of the bioactive compounds expressed in mg of gallic acid per 100 g of the pulp on a dry base were 13.9 ± 0.004;5.9 ± 0.001 and 126.3 ± 0.004 for caffeic, p-coumaric and ferulic acids, respectively. The best shelf-life followed by ABTS in eight assays was between 28.8 and 31.5 weeks using maltodextrin and modified starch, MD:MS (1/4:3/4) and MD:MS (0:1), respectively. In conclusion, ABTS is the best method to measure the AOA in banana passion fruit because it correlated with the phenolic compounds better than DPPH and FRAP methods. Additionally, two options were found to protect the AOA and to extent the shelf-life of the passion fruit by spray-drying, with mixtures of encapsulants widely used in the food industry.
基金Project supported by the National Key Research and Development Program of China(No.2018YFD0400305)the Modern Agro-industry Technology Research System of China(No.CARS-40-K26)the“One Belt and One Road”International Science and Technology Cooperation Program of Zhejiang,China(No.2019C04022)。
文摘Immunoglobulin Y(Ig Y)is an effective orally administered antibody used to protect against various intestinal pathogens,but which cannot tolerate the acidic gastric environment.In this study,Ig Y was microencapsulated by alginate(ALG)and coated with chitooligosaccharide(COS).A response surface methodology was used to optimize the formulation,and a simulated gastrointestinal(GI)digestion(SGID)system to evaluate the controlled release of microencapsulated Ig Y.The microcapsule formulation was optimized as an ALG concentration of 1.56%(15.6 g/L),COS level of 0.61%(6.1 g/L),and Ig Y/ALG ratio of 62.44%(mass ratio).The microcapsules prepared following this formulation had an encapsulation efficiency of 65.19%,a loading capacity of 33.75%,and an average particle size of 588.75μm.Under this optimum formulation,the coating of COS provided a less porous and more continuous microstructure by filling the cracks on the surface,and thus the GI release rate of encapsulated Ig Y was significantly reduced.The release of encapsulated Ig Y during simulated gastric and intestinal digestion well fitted the zero-order and first-order kinetics functions,respectively.The microcapsule also allowed the Ig Y to retain 84.37%immune-activity after 4 h simulated GI digestion,significantly higher than that for unprotected Ig Y(5.33%).This approach could provide an efficient way to preserve Ig Y and improve its performance in the GI tract.
文摘In this study, linoleic acid (LA) was encapsulated in the presence or absence of quercetin into a dual polymer system of whey protein and kappa-carrageenan using power ultrasound. Atomic Force Microscopy (AFM) and FlowCam imaging technology were used for imaging and size determination of nano-and micro-capsules. Differential scanning calorimeter (DSC) was used to determine the glass transition temperature (Tg) of the freeze-dried nanocapsules. In order to examine the effect of water activity (aw) on the release profile of the encapsulated LA, the nanocapsules were equilibrated over saturated salt solution conditions corresponding to the range of aw between 0.333 and 0.769 in evacuated desiccators at room temperature. Gravimetric measurements of the steady state linoleic acid (LA) contents were conducted. The anti-oxidant activity of quercetin and the stability of encapsulated LA toward long term and thermally induced rancidity was investigated. The capsules were in the nanosize regime and 83% of the LA was effectively encapsulated. Furthermore, at aw of 0.764, the highest percentage of LA (74%) was released from the expelling nanocapsules. Quercetin was found to exhibit protective antioxidant effect against time-dependent oxidation and thermally induced rancidity of LA. Water activity values of 0.662 and 0.764 provided ideal humidity and pressure conditions for sustained release of nanoencapsulated LA at room temperature.
基金financial supports by the Shenzhen Science and Technology Project(No.JCYJ20180306172823786)the National Natural Science Foundation of China(Nos.21876141,NFFTBS-J1310024)。
文摘A dual emission sensing film has been prepared for colorimetric temperature sensing using CsPbBr_(3)perovskite nanocrystals(CsPbBr_(3)NCs)and manganese doped potassium fluorosilicate(K_(2)SiF_(6):Mn^(4+),KSF)encapsulated in polystyrene by a microencapsulation strategy.The CsPbBr_(3)-KSF-PS film shows good temperature sensing response from 30℃to 70℃,with a relative temperature sensitivity(Sr)up to 10.31%℃^(−1) at 45℃.Meanwhile,the film maintains more than 95%intensity after 6 heating-cooling cycles and keeps its fluorescence characteristics after 3 months.The film can be used to monitor temperature change by naked eye under a UV lamp.In particular,the temperature discoloration point of the sensing film can be controlled by the ratio change of CsPbBr_(3):KSF to expand its applications.The study of the CsPbBr_(3)-KSF-PS sensing mechanism in this work is helpful to provide effective strategies for the design of reliable,high sensitivity and stable temperature sensing system using CsPbBr_(3)NCs.
文摘L-ascorbic acid is a water soluble vitamin (vitamin C) widely used as an additive in foods and cosmetics. It has high instability against certain environmental factors;the main cause of its deterioration is oxidation. Microencapsulation is an effective protection technique of L-ascorbic acid from its degradation reactions. This work is focused on the encapsulation of L-ascorbic acid by spray drying technique using sodium alginate as wall material. The microcapsules morphology was observed by scanning electron microscopy (SEM) and the encapsulation efficiency was determined by spectrophotometric analysis. Results showed that encapsulation efficiency was of 93.48% and after 30 days was of 92.55%;differences were not significant, so that the stability of L-ascorbic acid was not affected. Encapsulation yields obtained were low, at around 30%, but the microcapsules morphology obtained is spherical.
文摘Enzymes have been used in detergents over the years. They can improve the detergent’s efficiency due to their activities against hard stains. Nevertheless, enzymes cannot maintain their properties indefinitely, since they are exposed to stress factors, like temperature, pH, mechanical processes and others. Consequently, enzymes lose their structure and they are not functional. For this reason, microencapsulating these proteins is a feasible solution to improve their use in industrial processes and commercial products. Spray drying technology has been selected because a lot of scientific literature proved its useful application in a variety of industries. In particular, savinase and lipase are the two encapsulated enzymes in this work. Savinase attacks proteins and lipase removes fats, so they are suitable enzymes for detergent industry. Arabic gum has been used as wall material. Morphology, size and activity of the obtained microcapsules have been analyzed in order to find the best conditions to produce them. In conclusion, useful microcapsules of lipase and savinase can be obtained with the mentioned technology.
文摘[Objective] The aim of this study was to explore the microencapsulation of peony oil. [Method] Using [5-cyclodextrin, Arabic gum and soy protein as the wall materials and by the preparation technology of peony oil through spray drying, we conducted single factor experiments and orthogonal experiment analysis of the tech- nical parameters of peony oil microencapsulation. [Result] The optimal parameters of peony oil microcapsule preparation were acquired. The ratio of three wall materials （~5-cyclodextrin, Arabic gum, and soy protein） is 3：1：2, the solid content is 35%, the ratio of core-wall material is 3：1, emulsifier dosage is 0.2%, and the embedding rate of peony oil reaches 92%. [Conclusion] This technology produced the highest em- bedding rate and it laid the foundation for further development of peony oil.
基金Brazilian Federal Agency for Support and Evaluation of Graduate Education―CAPES for the financial help
文摘Acrocomia aculeata (Jacq.) Lodd. shows possibilities for pharmaceutical, food and chemical use. However, its application is limited due to the loss of its bioactive components. Microencapsulation may be an alternative to reduce such problems. A step-by-step optimization approach was used in this work for preservation of bioactive compounds. The applied technique to microencapsulate the Acrocomia aculeata oil was efficient, producing between 64% and 99% of microcapsules and 59% to 97% of encapsulated oil. In the experimental design, temperature was the parameter that significantly influenced the carotenoids of microcapsules. Complex coacervation helped to preserve carotenoids and the antioxidant activity, and an interaction between the temperature and the content was observed for such preservation.
文摘With the microencapsulation technique for immunoisolation of transplanted tissues, a study on pituitary transplantation was performed in our lab. Mixed fetal pituitary hypothalamic nigral cells were microencapsulated and cultured to investigate the secretion of growth hormone (GH), prolactin(PRL) and PRL releasing function stimulated by thyrotropin releasing hormone (TRH) in the medium. Rabbits were immunized with the encapsulated cells for 50 days. The results revealed that: ①GH, PRL could be secreted into medium through the capsules; ②PRL concentration augmented when TRH was added to the medium; ③No antibody against the fetal brain tissue could be detected in rabbit serum. These indicated that the material and the procedure of microencapsulation did not disturb the viability and function of encapsulated cells; the membrane of the microencapsulation was permeable to the pituitary hormones and hypothalamic factors, and had the function of immunoisolation.
基金Supported by the National Natural Science Foundation of China(51562023)the Natural Science Foundation of Gansu Provence(145RJZA185)the National science and technology support project(2014BAA01B01)
文摘Aiming to identify the validity of fabricating microencapsulated phase change material(PCM) with polymethylmethacrylate(PMMA) by ultraviolet curing emulsion polymerization method using iron(III) chloride as photoinitiator,SA/PMMA microcapsules were prepared and various techniques were employed to determine the ignition mechanism,structural characteristics and thermal properties of the composite.The results shown that the microcapsules containing SA with maximum percentage of 52.20 wt% formed by radical mechanism and only physical interactions existed in the components both in the prepared process and subsequent use.The phase change temperatures and latent heats of the microencapsulated SA were measured as 55.3 °C and 102.1 J·g^(-1) for melting,and 48.8 °C and 102.8 J·g^(-1) for freezing,respectively.Thermal gravimetric analysis revealed that SA/PMMA has good thermal durability in working temperature range.The results of accelerated thermal cycling test are all shown that the SA/PMMA have excellent thermal reliability and chemical stability although they were subjected 1000 melting/freezing cycles.In summary,the comparable thermal storage ability and good thermal reliability facilitated SA/PMMA to be considered as a viable candidate for thermal energy storage.The successful fabrication of SA/PMMA capsules indicates that ferric chloride is a prominent candidate for synthesizing PMMA containing PCM composite.
基金supported by the National Natural Science Foundation of China,No.81260190the Natural Science Foundation of Jiangxi Province of China,No.20132BAB205023+1 种基金a grant from the Science and Technology Research Program of Department of Education of Jiangxi Province in China,No.GJJ13159a grant from the Science and Technology Program of Department of Health of Jiangxi Province,No.20132019
文摘Olfactory bulb tissue transplantation inhibits P2X2/3 receptor-mediated neuropathic pain. However, the olfactory bulb has a complex cellular composition, and the mechanism underlying the action of purified transplanted olfactory ensheathing cells（OECs） remains unclear. In the present study, we microencapsulated OECs in alginic acid, and transplanted free and microencapsulated OECs into the region surrounding the injured sciatic nerve in rat models of chronic constriction injury. We assessed mechanical nociception in the rat models 7 and 14 days after surgery by measuring paw withdrawal threshold, and examined P2X2/3 receptor expression in L4–5 dorsal root ganglia using immunohistochemistry. Rats that received free and microencapsulated OEC transplants showed greater withdrawal thresholds than untreated model rats, and weaker P2X2/3 receptor immunoreactivity in dorsal root ganglia. At 14 days, paw withdrawal threshold was much higher in the microencapsulated OEC-treated animals. Our results confirm that microencapsulated OEC transplantation suppresses P2X2/3 receptor expression in L4–5 dorsal root ganglia in rat models of neuropathic pain and reduces allodynia, and also suggest that transplantation of microencapsulated OECs is more effective than transplantation of free OECs for the treatment of neuropathic pain.
