Edible biopolymer films were developed from the exopolysaccharides (EPS) extracted from Weissella confusa 113-2. The optimum composition for film formation was determined using the response surface analysis with the explanatory variables of the EPS (0.5-5.5%) and glycerol (0.5-5.5%) concentrations and the response variable of film elastic modulus (EM). The mass ratio of distilled water to solids was set constant (14:1). Tensile strength (TS), percentage elongation at break (%E), EM, water vapor permeability (WVP) of EPS films were evaluated. The glass transition temperatures of the films were also determined by a dynamic mechanical analysis. The optimum mass ratio of EPS to glycerol was 0.754:0.375. The WVP, TS, %E, and EM of the film under the optimal composition were 3.53±0.21 g·mm/kPa·h·m2, 7.03±0.49 MPa, 84.82±12.31%, and 62.03±6.93 MPa, respectively. The glass transition temperature varied from 54 to 83 °C. The EPS film has the potential to be applied to food products as an edible film with physical and barrier properties comparable to other biopolymer edible films.

Geneally, rice seeds regardless indica or japonica are showing low germination ratio or completely lost germination ability together with lost of good eating quality under high temperature and humidity conditions. Thus, this study was designed to evaluate a longevity for conservation of good eating quality during long term storage in rice. For the longevity evaluation, germination ability was studied after 5 days of high temperature and humidity stress (50℃/RH 95%). Dharial, originated from Bangladesh and showing weedy type with red pericarp, was selected as a good donor for longevity genes. A mutant was developed from Dharial through EMS mutagenesis and two populations of Dharial/4*Ilmibyeo and Dharial/4*Gopumbyeo were also developed for genetic study. In the 2-DE analysis followed by MALDI-TOF MS with wild and mutant lines, several candidate genes were identified. In the longevity test of two populations, a few lines showing good germination ability after high temperature and humidity stress were selected and subjected to confirm the relationships between longevity and conservation of good eating quality under long term storage.

AFLP markers were successfully employed to detect genetic relationship and genetic variation within and between Oryza species. Analysis of 59 accessions of Oryza species with six AFLP prim er combinations detected a total num ber of 715 polym orphic bands