• Natural Product Sciences
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• v.11 no.3
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• pp.183-187
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• 2005

The objective of the present study was to determine the possible immune-enhancing effects of a substance extracted from a submerged culture of Lentinus edodes with rice bran (SLRB). According to the results obtained by measuring the in vitro macrophage activity of the exo-biopolymer from SLRB, it appears to exhibit activity similar to that of LPS, and this activity seems to occur in a dose-dependent manner. According to the results obtained by measuring splenocyte proliferation, the exo-biopolymer appears to induce an increase in proliferation of approximately 1.4-fold compared to the control group. We measured the proliferation of bone marrow cells in order to evaluate gut immunity and, according to our results, proliferation was increased to 109% that of the control group, and was similar to that associated with LPS. In order to characterize the enhancement of immunological activity in vivo, we orally administered the exo-biopolymer (25, 50, 250 mg/kg bw) to C3H/He mice, and then measured the macrophage activity, determining that the activity was higher than that of the controls at concentrations of 50 and 250 mg/kg. Therefore, the exo-biopolymer from SLRB can be considered to be a useful a BRM agent, as it clearly allows some protection against immunological diseases.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.6
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• pp.645-653
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• 2021

Biopolymer is a general concept for high molecular compounds produced by living organisms. Among them, the xanthan and β-glucan, which are organic polymer mixture produced by micro-organisms, are mainly used to increase the viscosity of a substance. And diluting in water and mixing with sand or clay can increase compressive strength and shear strength. In this study, mixed soil prepared by mixing soil with xanthan and beta-glucan based biopolymers specially developed for the purpose of increasing soil strength was applied to the river bank revetment, and changes during winter were measured using ground LiDAR. As a result of analyzing winter changes in major sections using three-dimensional point cloud data obtained through ground LiDAR, there were no changes to the extent that it was difficult to confirm with the naked eye in the two sections coated with biopolymer blended soil. However, soil loss due to Rill erosion was confirmed in the natural embankment section where biopolymer blended soil was not used.

• Geomechanics and Engineering
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• v.21 no.5
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• pp.413-422
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• 2020

The choice of eco-friendly materials for ground improvement is a necessary way forward for sustainable development. Adapting naturally available biopolymers will render the process of soil stabilization carbon neutral. An attempt has been made to use β-glucan, a natural biopolymer for the stabilization of lean clay as a sustainable alternative with specific emphasis on comprehending the effect of confining stresses on lean clay through triaxial compression tests. A sequence of laboratory experiments was performed to examine the various physical and mechanical characteristics of β-glucan treated soil (BGTS). Micro-analysis through micrographs were used to understand the strengthening mechanism. Results of the study show that the deviatoric stress of 2% BGTS is 12 times higher than untreated soil (UTS). The micrographs from Scanning Electron Microscopy (SEM) and the results of the Nitrogen-based Brunauer Emmett Teller (N₂-BET) analysis confirm the formation of new cementitious fibres and hydrogels within the soil matrix that tends to weld soil particles and reduce the pore spaces leading to an increase in strength. Hydraulic conductivity (HC) and compressibility reduced significantly with the biopolymer content and curing period. Results emphases that β-glucan is an efficient and sustainable alternative to the traditional stabilizers like cement, lime or bitumen.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.480-490
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• 2003

An innovative biopolymer known as the Rhizobian gum has been developed in France, which shows some dramatic refreshing effect on the skin. The origin of this innovative project takes its source in the natural environment, and in particular the natural environment of the roots of sunflowers and wheat, where a symbiotic bacterium has been discovered. It is a Rhizobium bacterium, which is hosted by the roots, and which is able to synthesize a specific polymer showing a dramatic water binding capacity. This polymer is in particular synthesized in period of drought, and its biological role is to concentrate the small amount water present in the soil in order to take it available for the root, which becomes then able to absorb it. This vital mechanism allows the plant to survive despite a severe climatic environment. This basic research has been conducted in collaboration whit the French National centre of scientific Research (CNRS), and has lead to the isolation of the Rhizobium bacteria. Rhizobian gum is a branched biopolymer consisting in the repetition of a polysaccharide unit of 3 molecules of glucose, 3 molecules of galactose and 1 molecule of glucuronic acid, whit one pyruvate group an average 1.6 acetyl groups. The fresh effect of Rhizobian gum is a strong sensorial impact that 100 ％ of the consumers are able to perceive, and which is judged very pleasant by most of them. In addition to this, a large majority of consumers are perceived, and which is judge very pleasant by most of them. In addition to this, a large majority of consumers also feel a very pleasant relaxing sensation. Smoothness and softness are also felt by most consumers and qualified positively by most of them. These qualities guarantee a strong impact on today's consumers.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.50-60
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• 2003

An innovative biopolymer known as the Rhizobian gum has been developed in France, which shows some dramatic refreshing effect on the skin. The origin of this innovative project takes its source in the natural environment, and in particular the natural environment of the roots of sunflowers and wheat, where a symbiotic bacterium has been discovered. It is a Rhizobium bacterium, which is hosted by the roots, and which is able to synthesize a specific polymer showing a dramatic water binding capacity. This polymer is in particular synthesized in period of drought, and its biological role is to concentrate the small amount water present in the soil in order to take it available for the root, which becomes then able to absorb it. This vital mechanism allows the plant to survive despite a severe climatic environment. This basic research has been conducted in collaboration whit the French National centre of scientific Research (CNRS), and has lead to the isolation of the Rhizobium bacteria. Rhizobian gum is a branched biopolymer consisting in the repetition of a polysaccharide unit of 3 molecules of glucose, 3 molecules of galactose and 1 molecule of glucuronic acid, whit one pyruvate group an average 1.6 acetyl groups. The fresh effect of Rhizobian gum is a strong sensorial impact that 100 ％ of the consumers are able to perceive, and which is judged very pleasant by most of them. In addition to this, a large majority of consumers are perceived, and which is judge very pleasant by most of them. In addition to this, a large majority of consumers also feel a very pleasant relaxing sensation. Smoothness and softness are also felt by most consumers and qualified positively by most of them. These qualities guarantee a strong impact on today's consumers.

• Journal of Korea Water Resources Association
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• v.53 no.3
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• pp.167-179
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• 2020

Recently, new levee material has been developed to enhance natural soil strength and vegetation growth using biopolymer. In the study, critical tractive force of vegetated mats mixed with biopolymer mixed soil has been evaluated to apply the mixed soil to levee construction material. The mixed soil has been produced by mixing beta-glucan, clay, and sand. Full scale test bodies have been constructed with 3 cm thick of the mixed soil. Total 4 test bodies have been constructed and experimented. Critical tractive forces have been evaluated by observation and measurement of failure conditions and soil loss. Although performance of the vegetated revetments are affected by vegetation coverage conditions, the critical tractive forces are shown about 40 N/㎡ and the critical velocities are shown about 4 m/sec by full scale experiment. Erosion resistance is also enhanced by combination of root and net with mat materials.

• Ecology and Resilient Infrastructure
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• v.7 no.3
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• pp.208-217
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• 2020

A biopolymer based on microorganism-derived β-glucan and xanthan gum is being studied as a new eco-friendly material that stabilizes the riverbank slope, and also promotes vegetation growth. However, it is still inconclusive whether biopolymers have a positive effect on plant performance in the riverbanks which are subjected to various climatic factors and plant competitions. For a practical ecological evaluation of the biopolymers, their effect on plant growth promotion was studied in a natural environment. Considering the relationship between competition and plant community formation, the effects of biopolymers on competition were also investigated. For four plant species (Echinochloa crus-galli, Pennisetum alopecuroides, Leonurus japonicus, and Coreopsis lanceolata), the biopolymer effects under intra/interspecific competition were tested at the riverbank (20 m × 10 m) near Samjigyo Bridge in Damyang-gun, Jeollanam-do. A biopolymer powder was mixed with water and commercial soil following the manufacturer's recommendations. The soil mixed with the biopolymer was filled in a pot or applied to the surface of the commercial soil with a thickness of 3 cm. Across the competition treatments, the biopolymer treatment promoted root growth of the target plant species and decreased the specific leaf area. The total biomass and shoot dry weight of P. alopecuroides increased in response to the biopolymer treatment. The competition treatment decreased the total biomass and shoot dry weight compared to the case without competition. Notably, such a competitive effect was similar in all the biopolymer treatments. Thus, biopolymers, when mixed with soil, promote the growth of some plant species, but do not appear to affect the competitive ability of plants.

• Geomechanics and Engineering
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• v.12 no.5
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• pp.831-847
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• 2017

Conventional geotechnical engineering soil binders such as ordinary cement or lime have environmental issues in terms of sustainable development. Thus, environmentally friendly materials have attracted considerable interest in modern geotechnical engineering. Microbial biopolymers are being actively developed in order to improve geotechnical engineering properties such as aggregate stability, strength, and hydraulic conductivity of various soil types. This study evaluates the geotechnical engineering shear behavior of sand treated with xanthan gum biopolymer through laboratory direct shear testing. Xanthan gum-sand mixtures with various xanthan gum content (percent to the mass of sand) and gel phases (initial, dried, and re-submerged) were considered. Xanthan gum content of 1.0% sufficiently improves the inter-particle cohesion of cohesionless sands 3.8 times and more (up to 14 times for dried state) than in the untreated (natural) condition, regardless of the xanthan gum gel condition. In general, the strength of xanthan gum-treated sand shows dependency with the rheology and phase of xanthan gum gels in inter-granular pores, which decreases in order as dried (biofilm state), initial (uniform hydrogel), and re-submerged (swollen hydrogel after drying) states. As xanthan gum hydrogels are pseudo-plastic, both inter-particle friction angle and cohesion of xanthan gum-treated sand decrease with water adsorbed swelling at large strain levels. However, for 2% xanthan gum-treated sands, the re-submerged state shows a higher strength than the initial state due to the gradual and non-uniform swelling behavior of highly concentrated biofilms.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.297-298
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• 2003

Chitin is a natural biopolymer that, with its derivative chitosan, has been represented as a biomaterial with considerable potential in wide ranging medical applications. But there are some limitations in using chitosan as attained, for instance, the problem of water solubility$^1$. In order to use chitosan in various applications (e.g. drug carrier), chemical modifications are often necessary$^2$. (omitted)

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.718-720
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• 2005