In this study, pitch crosslinked by oxygen function groups was made into activated carbon (AC) and pore structure was observed. The oxygen functional groups were introduced by the addition of waste PET for pitch synthesis. Activation agent ratios used to obtain the AC during the activation process were 1:1, 1:2 and 1:4 (pitch:KOH, w/w). The oxygen content in the prepared pitch was characterized by elemental analysis. Also, the molecular weight of pitch was investigated by MALDITOF. Specific surface area and micropore volume of the prepared AC were determined by the argon adsorption–desorption analysis and calculated using the Brunauer–Emmett–Teller and Horvath–Kawazoe equations, respectively. Micropore fraction of PET-free AC was smaller than that of PET-added AC. At high activation agent ratio, mesopores were created when the micropore structure collapsed. However, in the PET-added AC, due to the oxygen crosslinking effect, the micropore structure and micropore size were maintained even at a high activation agent ratio. Therefore, PET AC was found to have a higher micropore fraction than that of PET-free AC.

The mannanase, cellulase and xylanase-producing thermophilic bacteria, designated EJ3, was isolated from fresh spent mushroom (Pleurotus eryngii) substrates taken from the DOJUN farm located in Keyongnam, Korea. The isolate EJ3 was facultatively anaerobic and grew at temperature ranging from 20℃ to 60℃ with an optimal temperature of 37℃. The DNA G+C content of the isolate EJ3 was 45 mlo%. The major fatty acids were anteiso-15:0 (38.9%), 17:0 (7.4%), and iso-15:0 (38.2%). The 16S rRNA gene sequence similarity between the isolate EJ3 and other Bacillus strains varied from 97% to 99%. In the phylogenetic analysis based on these sequences, the isolate EJ3 and Bacillus subtilis clustered within a group and separated from other species of Bacillus. Based on the physiological and molecular properties, the isolate EJ3 was classified within the genus Bacillus as Bacillus subtilis EJ3. The optimal growth condition of B. subtilis EJ3 were pH 6.0 and 55℃, respectively.

This study was conducted to evaluate the feeding value of the spent mushroom (Pleurotus eryngii) substrates (SMS) in laying hens (Hy-Line Brown). The fresh spent mushroom (Pleurotus eryngii) substrates collected from the DOJUN farm were fermented with Bacillus subtilis EJ3 for 2 weeks. A total of twenty-four laying hens were fed corn-soy based experimental diets containing 0% (control), 5% (T1), 10% (T2) and 15%(T3) fermented SMS for 7 weeks. There were no significant differences among the treatments in egg production, egg weight, egg mass, feed conversion and viability during the experimental period. Feed intake was significantly lowered in control (118.3 g) than T1 (121.9 g), T2 (120.3 g) and T3 (122.4 g). There were no significant differences among the treatments eggshell breaking strength, thickness and haugh unit, whereas the yolk color of T1, T2 and T3 were significantly heavy than T0. The palatability of boiled meat was significantly better in the T3 laying hens than in the T0 laying hens. In conclusion, fermented SMS can be used as resource of feed in laying hen feed at 5.0-15% level without effect on performance and egg qualify.