• Title/Summary/Keyword: Chitosan membrane

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Microencapsulation of Lactic Acid Bacteria (LAB)

  • Feucht, Andreas;Kwak, Hae-Soo
    • Food Science of Animal Resources
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    • v.33 no.2
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    • pp.229-238
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    • 2013
  • Lactic acid bacteria (LAB) are added to different food products for a long time due to health beneficial effects on human host. LAB is applied in dairy products, such as yoghurt, cheese, and various fermented products, and also in non-dairy products, such as sausages. However, reaching the human gut alive as well as in a sufficient cell amount to exert positive health effects is still a big challenge, due to LAB sensitive character and vulnerability against harsh and detrimental conditions in human digestive system. Keeping physiological activity of sensitive LAB strains alive is for the formulation of novel food products with a probiotic health claim of utmost interest, thus microencapsulation has been applied and investigated as a promising technique for a good and reliable protection. Microencapsulation allows reduced cell injury or cell loss by retaining cells within the encapsulating membrane and can be enforced by spray-drying, emulsion, extrusion, and a range of other technologies in combination with an appropriate coating material, such as alginate, chitosan, and mixture of these two polymers. In this review, established and well-studied microencapsulation techniques with their favored coating materials, as well as the recent applications of microencapsulated LAB into dairy products will be discussed.

Modified Graphene Oxide-Based Adsorbents Toward Hybrid Membranes for Organic Dye Removal Application

  • Thi Sinh, Vo;Khin Moe, Lwin;Sun, Choi;Kyunghoon, Kim
    • Composites Research
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    • v.35 no.6
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    • pp.402-411
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    • 2022
  • In this study, the channels-contained hybrid membranes have been fabricated through the incorporation of glass fibers and GO sheets (GO/glass fibers, GG), or a mixture of chitosan/GO (CS/GO/glass fibers, CGG), as hybrid membranes using in organic dye removal. The material properties are well investigated the terms in the morphological, chemical, crystal, and thermal characterizations for verifying interactions in their formed structure. These hybrid membranes have been fitted well in pseudo-second order and Langmuir models that are associated with chemical adsorption and a monolayer approach, respectively. The highest adsorption ability of methylene blue and methyl orange reached 59.40 mg/g and 229.07 mg/g (GG); and 287.47 mg/g and 252.91 mg/g (CGG), which is more enhanced than that of previous GO-based other adsorbents. Moreover, the dye separation on these membranes could be favorable to superb sealing and trapping dye molecules from water instead of only the dye connection occurring on their surface, regarding the physically sieving effect. The membranes can also be reused within two and three adsorbing-desorbing cycles on the GG and CGG ones, respectively. These membranes can become future adsorbents to be applied for wastewater treatment due to their structural features.

Molecular Weight Distribution Inside and Outside Capsules Using Coencapsulating Technology (공동캡슐화를 이용한 Capsule 내외부의 분자량 분포)

  • 이기선;임현수
    • KSBB Journal
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    • v.16 no.4
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    • pp.321-326
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    • 2001
  • The change of molecular weight inside and outside a capsule produced using coencapsulating technology was investigated. Chitosan and chitosanase were enveloped in this membrane and product released was a loaded the medium by the principle of size exclusion. The leakage of substrate corresponding to the agitation speed was controlled by adjusting the alginate and CaCO$_3$ concentrations. The optimal condition of alginate concentration and agitation speed were 0.5% and 40rpm, respectively. Membrane thickness and capsules diameter were 10 $\mu$m and approx. 3.0 - 1.5 mm, respectively. Molecular weight difference by concentration and alginate viscosity were of little significance. In accordance with the molecular weight distribution versus enzyme concentration relationship, low concentration of enzyme produced high molecular weight oligosaccharides. At a 1.5 mm capsule size the product diffusion rate to outer surface highest. The molecular weight distribution of the released oligosaccharides was ranged from 1000 to 6000 Da. More than 80% of the initial activity of encapsulated enzyme retained after 8hrs of reaction.

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Mineralized Polysaccharide Transplantation Modules Supporting Human MSC Conversion into Osteogenic Cells and Osteoid Tissue in a Non-Union Defect

  • Ge, Qing;Green, David William;Lee, Dong-Joon;Kim, Hyun-Yi;Piao, Zhengguo;Lee, Jong-Min;Jung, Han-Sung
    • Molecules and Cells
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    • v.41 no.12
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    • pp.1016-1023
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    • 2018
  • Regenerative orthopedics needs significant devices to transplant human stem cells into damaged tissue and encourage automatic growth into replacements suitable for the human skeleton. Soft biomaterials have similarities in mechanical, structural and architectural properties to natural extracellular matrix (ECM), but often lack essential ECM molecules and signals. Here we engineer mineralized polysaccharide beads to transform MSCs into osteogenic cells and osteoid tissue for transplantation. Bone morphogenic proteins (BMP-2) and indispensable ECM proteins both directed differentiation inside alginate beads. Laminin and collagen IV basement membrane matrix proteins fixed and organized MSCs onto the alginate matrix, and BMP-2 drove differentiation, osteoid tissue self-assembly, and small-scale mineralization. Augmentation of alginate is necessary, and we showed that a few rationally selected small proteins from the basement membrane (BM) compartment of the ECM were sufficient to up-regulate cell expression of Runx-2 and osteocalcin for osteoid formation, resulting in Alizarin red-positive mineral nodules. More significantly, nested BMP-2 and BM beads added to a non-union skull defect, self-generated osteoid expressing osteopontin (OPN) and osteocalcin (OCN) in a chain along the defect, at only four weeks, establishing a framework for complete regeneration expected in 6 and 12 weeks. Alginate beads are beneficial surgical devices for transplanting therapeutic cells in programmed (by the ECM components and alginate-chitosan properties) reaction environments ideal for promoting bone tissue.

Large scale enzymatic production of chitooligosaccharides and their biological activities (키토산올리고당의 효소적 대량생산 및 생리활성)

  • Kim, Se-Kwon;Shin, Kyung-Hoon
    • Food Science and Industry
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    • v.53 no.1
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    • pp.2-32
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    • 2020
  • In recent years, significant importance has been given to chitooligosaccharides (COS) due to its potent notable biological applications. COS can be derived from chitosan which is commonly produced by partially hydrolyzed products from crustacean shells. In order to produce COS, there are several approaches including chemical and enzymatic methods which are the two most common choices. In this regard, several new methods were intended to be promoted which use the enzymatic hydrolysis with a lower cost and desired properties. Hence, the dual reactor system has gained more attention than other newly developed technologies. Enzymatic hydrolysis derived COS possesses important biological activities such as anticancer, antioxidant, anti-hypersentive, anti-dementia (Altzheimer's disease), anti-diabeties, anti-allergy, anti-inflammatory, etc. Results strongly suggest that properties of COS can be potential materials for nutraceutical, pharmaceutical, and cosmeceutical product development.