Different strategies are studied to incorporate lipid-soluble bioactive molecules into water-based food systems. However, these systems solely cannot protect the core compound through the storage period, especially when the core is exposed to environmental stress factors. Water soluble fraction of the crude extract from Enteromorpha prolifera was analyzed for its physicochemical characteristics including chemical composition, structure, rheological and thermal properties. The extract was added to O/W emulsion system containing retinol and stabilized with Tween 20, WPI and sodium caseinate to improve storage stability through different modes of action; as a chelator of metal ions and as a scavenger of radicals. Storage stability was mainly determined by zeta potential, particle size distribution, and retinol retention.
The water-soluble extract of E.prolifera mainly consisted of anionic polysaccharide, while impurities of protein, mineral and other pigments were present. Mode of action analysis showed that the extracts had both ferrous ion chelating ability(EC50=0.67%) and free radical scavenging ability(EC50=0.23%), indicating a multifunctioning mechanism of the heterogeneous extract. Addition of extract (0.1%~1% in total emulsion) did not affect the physical stability during 1 week storage.
Protective materials are often added to food systems to improve the stability of core materials but excessive use of additives may be repulsive to consumers. In contrast, the optimum concentration range of E.prolifera extract is much lower compared to that of conventional usage of other materials and has lower toxicity to that of strong chelators while providing effective protection.
O/W emulsion is usually adopted to incorporate lipid-soluble bioactive molecules into water-based food systems. However, the emulsion system solely cannot protect the core compound through the storage period, especially in cases when the core is unstable to environmental stress factors. Wall materials such as maltodexrin and chelators such as EDTA-Na are added to improve the stability of core materials but excessive use of additives may be repulsive to consumers. In this study, water soluble fraction of the crude polysaccharide extracted from Enteromorpha prolifera, a type of green algae commonly found in the southern coast of Korean sea, was added to an O/W emulsion system containing retinol to improve storage stability through different modes of action; as a chelator of metal ions, as a scavenger of free radicals and as a wall material. The radical scavenging ability and chelating ability of E.prolifera polysaccharide were determined in solution state. Particle size, zeta potential and retinol retention rate were measured as stability markers in emulsion. Emulsion stability increased and then decreased as the amount of polysaccharide increased from 1 to 5 mg. This optimum concentration is much lower compared to that of conventional usage of wall materials, therefore less affecting the physical characteristics of emulsion while providing effective protection.
Woolly apple aphid, Eriosoma lanigerum, one of the pests occurring in apple do damages on the branch and bastard slip nearby ground roots by sucking sap. Recently, seasonal population of this pest steadily increased but has scarcity the basic data relating to its ecology. This study was conducted to investigate the infested orchard ratio, environmental analysis of occurred orchard, seasonal population and parasite rate by Aphelinus mali, a natural enemy for woolly apple aphid, from 30 to 34 apple orchards, at 11 to 13 major apple producing areas in Gyeongsang-namdo and Gyeongsang-bukdo, Geolla-bukdo, and Chungchung-bukdo, during 2012 to 2013. It showed infested orchard ratio as about 35% and population density started to increase from mid-May, with its optimal density in late-June and increased again in late-September. This pest found in various rootstocks where infested orchards and could not found any significant pattern. The damage appeared in 9 to 35 year-old trees, severed rather old trees than younger trees. Also, orchards that did not eliminate bastard slip were showed high occurrence pattern. Parasite rates of Aphelinus mali showed the difference among investigated orchards but the rates showed generally increased pattern since early- July.
Water quality of the Koejong-reservoir was estimated by using the ecological model to evaluate the effects of industrial sewage discharge. State variables consist of POC, DOC, phytoplankton, DIP, DIN, DO and COD. Initial conditions for the compartment are applied to the model based on the observed results. The reproducibility was found to be satisfactory with the relative error ranging between the calculated value and the observed value. Water quality simulation was conducted by applying additional industrial sewage discharge into the Koejong-reservoir. The concentrations of COD, Chl.a, DIP and COD showed fluctuations of a narrow range. The increment percentages of Chl.a, COD and DIP were 26.6%, 20.2% and 18.2%, respectively. In the case of DO, the concentration decreased 4.8%.
In order to improve the existing S-57 standard, International Hydrographic Organization(IHO) has developed S-100 standard, a Universal Hydrographic Data Model(UHDM) expanded from ISO 19100 series standard to hydrographic area, and is in the process of its implementation. International Maritime Organization(IMO) has established CMDS based on e-Navigation strategy data standard as International Association of Lighthouse Authorities(IALA) established IHDM based on aids to navigation data standard and each data standard is linked with the S-100 standard. Fundamental concept and core principles of S-100 standard is suitable not only for the development of a wide range of hydrographic data and service production standard, including the next generation ENC, but also the development of product specification of non-hydrographic area. This study has examined the operation principle of S-100 standard and analyzed its implementation process as e-Navigation data in relation with ENC. It also noted the utilization of S-100 standard based e-Navigation and its potential effect via examining the development cases of S-100 standard-based product specification, such as nautical publication, ship reporting and pilot request, digital routing guide, tide and water level transmission and other important data cases of e-Navigation field.